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Commit | Line | Data |
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8ae12a0d | 1 | /* |
ca632f55 | 2 | * SPI init/core code |
8ae12a0d DB |
3 | * |
4 | * Copyright (C) 2005 David Brownell | |
d57a4282 | 5 | * Copyright (C) 2008 Secret Lab Technologies Ltd. |
8ae12a0d DB |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify | |
8 | * it under the terms of the GNU General Public License as published by | |
9 | * the Free Software Foundation; either version 2 of the License, or | |
10 | * (at your option) any later version. | |
11 | * | |
12 | * This program is distributed in the hope that it will be useful, | |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | * GNU General Public License for more details. | |
8ae12a0d DB |
16 | */ |
17 | ||
8ae12a0d DB |
18 | #include <linux/kernel.h> |
19 | #include <linux/device.h> | |
20 | #include <linux/init.h> | |
21 | #include <linux/cache.h> | |
99adef31 MB |
22 | #include <linux/dma-mapping.h> |
23 | #include <linux/dmaengine.h> | |
94040828 | 24 | #include <linux/mutex.h> |
2b7a32f7 | 25 | #include <linux/of_device.h> |
d57a4282 | 26 | #include <linux/of_irq.h> |
86be408b | 27 | #include <linux/clk/clk-conf.h> |
5a0e3ad6 | 28 | #include <linux/slab.h> |
e0626e38 | 29 | #include <linux/mod_devicetable.h> |
8ae12a0d | 30 | #include <linux/spi/spi.h> |
74317984 | 31 | #include <linux/of_gpio.h> |
3ae22e8c | 32 | #include <linux/pm_runtime.h> |
f48c767c | 33 | #include <linux/pm_domain.h> |
025ed130 | 34 | #include <linux/export.h> |
8bd75c77 | 35 | #include <linux/sched/rt.h> |
ffbbdd21 LW |
36 | #include <linux/delay.h> |
37 | #include <linux/kthread.h> | |
64bee4d2 MW |
38 | #include <linux/ioport.h> |
39 | #include <linux/acpi.h> | |
b1b8153c | 40 | #include <linux/highmem.h> |
8ae12a0d | 41 | |
56ec1978 MB |
42 | #define CREATE_TRACE_POINTS |
43 | #include <trace/events/spi.h> | |
44 | ||
8ae12a0d DB |
45 | static void spidev_release(struct device *dev) |
46 | { | |
0ffa0285 | 47 | struct spi_device *spi = to_spi_device(dev); |
8ae12a0d DB |
48 | |
49 | /* spi masters may cleanup for released devices */ | |
50 | if (spi->master->cleanup) | |
51 | spi->master->cleanup(spi); | |
52 | ||
0c868461 | 53 | spi_master_put(spi->master); |
07a389fe | 54 | kfree(spi); |
8ae12a0d DB |
55 | } |
56 | ||
57 | static ssize_t | |
58 | modalias_show(struct device *dev, struct device_attribute *a, char *buf) | |
59 | { | |
60 | const struct spi_device *spi = to_spi_device(dev); | |
8c4ff6d0 ZR |
61 | int len; |
62 | ||
63 | len = acpi_device_modalias(dev, buf, PAGE_SIZE - 1); | |
64 | if (len != -ENODEV) | |
65 | return len; | |
8ae12a0d | 66 | |
d8e328b3 | 67 | return sprintf(buf, "%s%s\n", SPI_MODULE_PREFIX, spi->modalias); |
8ae12a0d | 68 | } |
aa7da564 | 69 | static DEVICE_ATTR_RO(modalias); |
8ae12a0d | 70 | |
eca2ebc7 MS |
71 | #define SPI_STATISTICS_ATTRS(field, file) \ |
72 | static ssize_t spi_master_##field##_show(struct device *dev, \ | |
73 | struct device_attribute *attr, \ | |
74 | char *buf) \ | |
75 | { \ | |
76 | struct spi_master *master = container_of(dev, \ | |
77 | struct spi_master, dev); \ | |
78 | return spi_statistics_##field##_show(&master->statistics, buf); \ | |
79 | } \ | |
80 | static struct device_attribute dev_attr_spi_master_##field = { \ | |
81 | .attr = { .name = file, .mode = S_IRUGO }, \ | |
82 | .show = spi_master_##field##_show, \ | |
83 | }; \ | |
84 | static ssize_t spi_device_##field##_show(struct device *dev, \ | |
85 | struct device_attribute *attr, \ | |
86 | char *buf) \ | |
87 | { \ | |
d1eba93b | 88 | struct spi_device *spi = to_spi_device(dev); \ |
eca2ebc7 MS |
89 | return spi_statistics_##field##_show(&spi->statistics, buf); \ |
90 | } \ | |
91 | static struct device_attribute dev_attr_spi_device_##field = { \ | |
92 | .attr = { .name = file, .mode = S_IRUGO }, \ | |
93 | .show = spi_device_##field##_show, \ | |
94 | } | |
95 | ||
96 | #define SPI_STATISTICS_SHOW_NAME(name, file, field, format_string) \ | |
97 | static ssize_t spi_statistics_##name##_show(struct spi_statistics *stat, \ | |
98 | char *buf) \ | |
99 | { \ | |
100 | unsigned long flags; \ | |
101 | ssize_t len; \ | |
102 | spin_lock_irqsave(&stat->lock, flags); \ | |
103 | len = sprintf(buf, format_string, stat->field); \ | |
104 | spin_unlock_irqrestore(&stat->lock, flags); \ | |
105 | return len; \ | |
106 | } \ | |
107 | SPI_STATISTICS_ATTRS(name, file) | |
108 | ||
109 | #define SPI_STATISTICS_SHOW(field, format_string) \ | |
110 | SPI_STATISTICS_SHOW_NAME(field, __stringify(field), \ | |
111 | field, format_string) | |
112 | ||
113 | SPI_STATISTICS_SHOW(messages, "%lu"); | |
114 | SPI_STATISTICS_SHOW(transfers, "%lu"); | |
115 | SPI_STATISTICS_SHOW(errors, "%lu"); | |
116 | SPI_STATISTICS_SHOW(timedout, "%lu"); | |
117 | ||
118 | SPI_STATISTICS_SHOW(spi_sync, "%lu"); | |
119 | SPI_STATISTICS_SHOW(spi_sync_immediate, "%lu"); | |
120 | SPI_STATISTICS_SHOW(spi_async, "%lu"); | |
121 | ||
122 | SPI_STATISTICS_SHOW(bytes, "%llu"); | |
123 | SPI_STATISTICS_SHOW(bytes_rx, "%llu"); | |
124 | SPI_STATISTICS_SHOW(bytes_tx, "%llu"); | |
125 | ||
6b7bc061 MS |
126 | #define SPI_STATISTICS_TRANSFER_BYTES_HISTO(index, number) \ |
127 | SPI_STATISTICS_SHOW_NAME(transfer_bytes_histo##index, \ | |
128 | "transfer_bytes_histo_" number, \ | |
129 | transfer_bytes_histo[index], "%lu") | |
130 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(0, "0-1"); | |
131 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(1, "2-3"); | |
132 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(2, "4-7"); | |
133 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(3, "8-15"); | |
134 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(4, "16-31"); | |
135 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(5, "32-63"); | |
136 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(6, "64-127"); | |
137 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(7, "128-255"); | |
138 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(8, "256-511"); | |
139 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(9, "512-1023"); | |
140 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(10, "1024-2047"); | |
141 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(11, "2048-4095"); | |
142 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(12, "4096-8191"); | |
143 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(13, "8192-16383"); | |
144 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(14, "16384-32767"); | |
145 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(15, "32768-65535"); | |
146 | SPI_STATISTICS_TRANSFER_BYTES_HISTO(16, "65536+"); | |
147 | ||
d9f12122 MS |
148 | SPI_STATISTICS_SHOW(transfers_split_maxsize, "%lu"); |
149 | ||
aa7da564 GKH |
150 | static struct attribute *spi_dev_attrs[] = { |
151 | &dev_attr_modalias.attr, | |
152 | NULL, | |
8ae12a0d | 153 | }; |
eca2ebc7 MS |
154 | |
155 | static const struct attribute_group spi_dev_group = { | |
156 | .attrs = spi_dev_attrs, | |
157 | }; | |
158 | ||
159 | static struct attribute *spi_device_statistics_attrs[] = { | |
160 | &dev_attr_spi_device_messages.attr, | |
161 | &dev_attr_spi_device_transfers.attr, | |
162 | &dev_attr_spi_device_errors.attr, | |
163 | &dev_attr_spi_device_timedout.attr, | |
164 | &dev_attr_spi_device_spi_sync.attr, | |
165 | &dev_attr_spi_device_spi_sync_immediate.attr, | |
166 | &dev_attr_spi_device_spi_async.attr, | |
167 | &dev_attr_spi_device_bytes.attr, | |
168 | &dev_attr_spi_device_bytes_rx.attr, | |
169 | &dev_attr_spi_device_bytes_tx.attr, | |
6b7bc061 MS |
170 | &dev_attr_spi_device_transfer_bytes_histo0.attr, |
171 | &dev_attr_spi_device_transfer_bytes_histo1.attr, | |
172 | &dev_attr_spi_device_transfer_bytes_histo2.attr, | |
173 | &dev_attr_spi_device_transfer_bytes_histo3.attr, | |
174 | &dev_attr_spi_device_transfer_bytes_histo4.attr, | |
175 | &dev_attr_spi_device_transfer_bytes_histo5.attr, | |
176 | &dev_attr_spi_device_transfer_bytes_histo6.attr, | |
177 | &dev_attr_spi_device_transfer_bytes_histo7.attr, | |
178 | &dev_attr_spi_device_transfer_bytes_histo8.attr, | |
179 | &dev_attr_spi_device_transfer_bytes_histo9.attr, | |
180 | &dev_attr_spi_device_transfer_bytes_histo10.attr, | |
181 | &dev_attr_spi_device_transfer_bytes_histo11.attr, | |
182 | &dev_attr_spi_device_transfer_bytes_histo12.attr, | |
183 | &dev_attr_spi_device_transfer_bytes_histo13.attr, | |
184 | &dev_attr_spi_device_transfer_bytes_histo14.attr, | |
185 | &dev_attr_spi_device_transfer_bytes_histo15.attr, | |
186 | &dev_attr_spi_device_transfer_bytes_histo16.attr, | |
d9f12122 | 187 | &dev_attr_spi_device_transfers_split_maxsize.attr, |
eca2ebc7 MS |
188 | NULL, |
189 | }; | |
190 | ||
191 | static const struct attribute_group spi_device_statistics_group = { | |
192 | .name = "statistics", | |
193 | .attrs = spi_device_statistics_attrs, | |
194 | }; | |
195 | ||
196 | static const struct attribute_group *spi_dev_groups[] = { | |
197 | &spi_dev_group, | |
198 | &spi_device_statistics_group, | |
199 | NULL, | |
200 | }; | |
201 | ||
202 | static struct attribute *spi_master_statistics_attrs[] = { | |
203 | &dev_attr_spi_master_messages.attr, | |
204 | &dev_attr_spi_master_transfers.attr, | |
205 | &dev_attr_spi_master_errors.attr, | |
206 | &dev_attr_spi_master_timedout.attr, | |
207 | &dev_attr_spi_master_spi_sync.attr, | |
208 | &dev_attr_spi_master_spi_sync_immediate.attr, | |
209 | &dev_attr_spi_master_spi_async.attr, | |
210 | &dev_attr_spi_master_bytes.attr, | |
211 | &dev_attr_spi_master_bytes_rx.attr, | |
212 | &dev_attr_spi_master_bytes_tx.attr, | |
6b7bc061 MS |
213 | &dev_attr_spi_master_transfer_bytes_histo0.attr, |
214 | &dev_attr_spi_master_transfer_bytes_histo1.attr, | |
215 | &dev_attr_spi_master_transfer_bytes_histo2.attr, | |
216 | &dev_attr_spi_master_transfer_bytes_histo3.attr, | |
217 | &dev_attr_spi_master_transfer_bytes_histo4.attr, | |
218 | &dev_attr_spi_master_transfer_bytes_histo5.attr, | |
219 | &dev_attr_spi_master_transfer_bytes_histo6.attr, | |
220 | &dev_attr_spi_master_transfer_bytes_histo7.attr, | |
221 | &dev_attr_spi_master_transfer_bytes_histo8.attr, | |
222 | &dev_attr_spi_master_transfer_bytes_histo9.attr, | |
223 | &dev_attr_spi_master_transfer_bytes_histo10.attr, | |
224 | &dev_attr_spi_master_transfer_bytes_histo11.attr, | |
225 | &dev_attr_spi_master_transfer_bytes_histo12.attr, | |
226 | &dev_attr_spi_master_transfer_bytes_histo13.attr, | |
227 | &dev_attr_spi_master_transfer_bytes_histo14.attr, | |
228 | &dev_attr_spi_master_transfer_bytes_histo15.attr, | |
229 | &dev_attr_spi_master_transfer_bytes_histo16.attr, | |
d9f12122 | 230 | &dev_attr_spi_master_transfers_split_maxsize.attr, |
eca2ebc7 MS |
231 | NULL, |
232 | }; | |
233 | ||
234 | static const struct attribute_group spi_master_statistics_group = { | |
235 | .name = "statistics", | |
236 | .attrs = spi_master_statistics_attrs, | |
237 | }; | |
238 | ||
239 | static const struct attribute_group *spi_master_groups[] = { | |
240 | &spi_master_statistics_group, | |
241 | NULL, | |
242 | }; | |
243 | ||
244 | void spi_statistics_add_transfer_stats(struct spi_statistics *stats, | |
245 | struct spi_transfer *xfer, | |
246 | struct spi_master *master) | |
247 | { | |
248 | unsigned long flags; | |
6b7bc061 MS |
249 | int l2len = min(fls(xfer->len), SPI_STATISTICS_HISTO_SIZE) - 1; |
250 | ||
251 | if (l2len < 0) | |
252 | l2len = 0; | |
eca2ebc7 MS |
253 | |
254 | spin_lock_irqsave(&stats->lock, flags); | |
255 | ||
256 | stats->transfers++; | |
6b7bc061 | 257 | stats->transfer_bytes_histo[l2len]++; |
eca2ebc7 MS |
258 | |
259 | stats->bytes += xfer->len; | |
260 | if ((xfer->tx_buf) && | |
261 | (xfer->tx_buf != master->dummy_tx)) | |
262 | stats->bytes_tx += xfer->len; | |
263 | if ((xfer->rx_buf) && | |
264 | (xfer->rx_buf != master->dummy_rx)) | |
265 | stats->bytes_rx += xfer->len; | |
266 | ||
267 | spin_unlock_irqrestore(&stats->lock, flags); | |
268 | } | |
269 | EXPORT_SYMBOL_GPL(spi_statistics_add_transfer_stats); | |
8ae12a0d DB |
270 | |
271 | /* modalias support makes "modprobe $MODALIAS" new-style hotplug work, | |
272 | * and the sysfs version makes coldplug work too. | |
273 | */ | |
274 | ||
75368bf6 AV |
275 | static const struct spi_device_id *spi_match_id(const struct spi_device_id *id, |
276 | const struct spi_device *sdev) | |
277 | { | |
278 | while (id->name[0]) { | |
279 | if (!strcmp(sdev->modalias, id->name)) | |
280 | return id; | |
281 | id++; | |
282 | } | |
283 | return NULL; | |
284 | } | |
285 | ||
286 | const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev) | |
287 | { | |
288 | const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver); | |
289 | ||
290 | return spi_match_id(sdrv->id_table, sdev); | |
291 | } | |
292 | EXPORT_SYMBOL_GPL(spi_get_device_id); | |
293 | ||
8ae12a0d DB |
294 | static int spi_match_device(struct device *dev, struct device_driver *drv) |
295 | { | |
296 | const struct spi_device *spi = to_spi_device(dev); | |
75368bf6 AV |
297 | const struct spi_driver *sdrv = to_spi_driver(drv); |
298 | ||
2b7a32f7 SA |
299 | /* Attempt an OF style match */ |
300 | if (of_driver_match_device(dev, drv)) | |
301 | return 1; | |
302 | ||
64bee4d2 MW |
303 | /* Then try ACPI */ |
304 | if (acpi_driver_match_device(dev, drv)) | |
305 | return 1; | |
306 | ||
75368bf6 AV |
307 | if (sdrv->id_table) |
308 | return !!spi_match_id(sdrv->id_table, spi); | |
8ae12a0d | 309 | |
35f74fca | 310 | return strcmp(spi->modalias, drv->name) == 0; |
8ae12a0d DB |
311 | } |
312 | ||
7eff2e7a | 313 | static int spi_uevent(struct device *dev, struct kobj_uevent_env *env) |
8ae12a0d DB |
314 | { |
315 | const struct spi_device *spi = to_spi_device(dev); | |
8c4ff6d0 ZR |
316 | int rc; |
317 | ||
318 | rc = acpi_device_uevent_modalias(dev, env); | |
319 | if (rc != -ENODEV) | |
320 | return rc; | |
8ae12a0d | 321 | |
e0626e38 | 322 | add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias); |
8ae12a0d DB |
323 | return 0; |
324 | } | |
325 | ||
8ae12a0d DB |
326 | struct bus_type spi_bus_type = { |
327 | .name = "spi", | |
aa7da564 | 328 | .dev_groups = spi_dev_groups, |
8ae12a0d DB |
329 | .match = spi_match_device, |
330 | .uevent = spi_uevent, | |
8ae12a0d DB |
331 | }; |
332 | EXPORT_SYMBOL_GPL(spi_bus_type); | |
333 | ||
b885244e DB |
334 | |
335 | static int spi_drv_probe(struct device *dev) | |
336 | { | |
337 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); | |
44af7927 | 338 | struct spi_device *spi = to_spi_device(dev); |
33cf00e5 MW |
339 | int ret; |
340 | ||
86be408b SN |
341 | ret = of_clk_set_defaults(dev->of_node, false); |
342 | if (ret) | |
343 | return ret; | |
344 | ||
44af7927 JH |
345 | if (dev->of_node) { |
346 | spi->irq = of_irq_get(dev->of_node, 0); | |
347 | if (spi->irq == -EPROBE_DEFER) | |
348 | return -EPROBE_DEFER; | |
349 | if (spi->irq < 0) | |
350 | spi->irq = 0; | |
351 | } | |
352 | ||
676e7c25 UH |
353 | ret = dev_pm_domain_attach(dev, true); |
354 | if (ret != -EPROBE_DEFER) { | |
44af7927 | 355 | ret = sdrv->probe(spi); |
676e7c25 UH |
356 | if (ret) |
357 | dev_pm_domain_detach(dev, true); | |
358 | } | |
b885244e | 359 | |
33cf00e5 | 360 | return ret; |
b885244e DB |
361 | } |
362 | ||
363 | static int spi_drv_remove(struct device *dev) | |
364 | { | |
365 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); | |
33cf00e5 MW |
366 | int ret; |
367 | ||
aec35f4e | 368 | ret = sdrv->remove(to_spi_device(dev)); |
676e7c25 | 369 | dev_pm_domain_detach(dev, true); |
b885244e | 370 | |
33cf00e5 | 371 | return ret; |
b885244e DB |
372 | } |
373 | ||
374 | static void spi_drv_shutdown(struct device *dev) | |
375 | { | |
376 | const struct spi_driver *sdrv = to_spi_driver(dev->driver); | |
377 | ||
378 | sdrv->shutdown(to_spi_device(dev)); | |
379 | } | |
380 | ||
33e34dc6 | 381 | /** |
ca5d2485 | 382 | * __spi_register_driver - register a SPI driver |
88c9321d | 383 | * @owner: owner module of the driver to register |
33e34dc6 DB |
384 | * @sdrv: the driver to register |
385 | * Context: can sleep | |
97d56dc6 JMC |
386 | * |
387 | * Return: zero on success, else a negative error code. | |
33e34dc6 | 388 | */ |
ca5d2485 | 389 | int __spi_register_driver(struct module *owner, struct spi_driver *sdrv) |
b885244e | 390 | { |
ca5d2485 | 391 | sdrv->driver.owner = owner; |
b885244e DB |
392 | sdrv->driver.bus = &spi_bus_type; |
393 | if (sdrv->probe) | |
394 | sdrv->driver.probe = spi_drv_probe; | |
395 | if (sdrv->remove) | |
396 | sdrv->driver.remove = spi_drv_remove; | |
397 | if (sdrv->shutdown) | |
398 | sdrv->driver.shutdown = spi_drv_shutdown; | |
399 | return driver_register(&sdrv->driver); | |
400 | } | |
ca5d2485 | 401 | EXPORT_SYMBOL_GPL(__spi_register_driver); |
b885244e | 402 | |
8ae12a0d DB |
403 | /*-------------------------------------------------------------------------*/ |
404 | ||
405 | /* SPI devices should normally not be created by SPI device drivers; that | |
406 | * would make them board-specific. Similarly with SPI master drivers. | |
407 | * Device registration normally goes into like arch/.../mach.../board-YYY.c | |
408 | * with other readonly (flashable) information about mainboard devices. | |
409 | */ | |
410 | ||
411 | struct boardinfo { | |
412 | struct list_head list; | |
2b9603a0 | 413 | struct spi_board_info board_info; |
8ae12a0d DB |
414 | }; |
415 | ||
416 | static LIST_HEAD(board_list); | |
2b9603a0 FT |
417 | static LIST_HEAD(spi_master_list); |
418 | ||
419 | /* | |
420 | * Used to protect add/del opertion for board_info list and | |
421 | * spi_master list, and their matching process | |
422 | */ | |
94040828 | 423 | static DEFINE_MUTEX(board_lock); |
8ae12a0d | 424 | |
dc87c98e GL |
425 | /** |
426 | * spi_alloc_device - Allocate a new SPI device | |
427 | * @master: Controller to which device is connected | |
428 | * Context: can sleep | |
429 | * | |
430 | * Allows a driver to allocate and initialize a spi_device without | |
431 | * registering it immediately. This allows a driver to directly | |
432 | * fill the spi_device with device parameters before calling | |
433 | * spi_add_device() on it. | |
434 | * | |
435 | * Caller is responsible to call spi_add_device() on the returned | |
436 | * spi_device structure to add it to the SPI master. If the caller | |
437 | * needs to discard the spi_device without adding it, then it should | |
438 | * call spi_dev_put() on it. | |
439 | * | |
97d56dc6 | 440 | * Return: a pointer to the new device, or NULL. |
dc87c98e GL |
441 | */ |
442 | struct spi_device *spi_alloc_device(struct spi_master *master) | |
443 | { | |
444 | struct spi_device *spi; | |
dc87c98e GL |
445 | |
446 | if (!spi_master_get(master)) | |
447 | return NULL; | |
448 | ||
5fe5f05e | 449 | spi = kzalloc(sizeof(*spi), GFP_KERNEL); |
dc87c98e | 450 | if (!spi) { |
dc87c98e GL |
451 | spi_master_put(master); |
452 | return NULL; | |
453 | } | |
454 | ||
455 | spi->master = master; | |
178db7d3 | 456 | spi->dev.parent = &master->dev; |
dc87c98e GL |
457 | spi->dev.bus = &spi_bus_type; |
458 | spi->dev.release = spidev_release; | |
446411e1 | 459 | spi->cs_gpio = -ENOENT; |
eca2ebc7 MS |
460 | |
461 | spin_lock_init(&spi->statistics.lock); | |
462 | ||
dc87c98e GL |
463 | device_initialize(&spi->dev); |
464 | return spi; | |
465 | } | |
466 | EXPORT_SYMBOL_GPL(spi_alloc_device); | |
467 | ||
e13ac47b JN |
468 | static void spi_dev_set_name(struct spi_device *spi) |
469 | { | |
470 | struct acpi_device *adev = ACPI_COMPANION(&spi->dev); | |
471 | ||
472 | if (adev) { | |
473 | dev_set_name(&spi->dev, "spi-%s", acpi_dev_name(adev)); | |
474 | return; | |
475 | } | |
476 | ||
477 | dev_set_name(&spi->dev, "%s.%u", dev_name(&spi->master->dev), | |
478 | spi->chip_select); | |
479 | } | |
480 | ||
b6fb8d3a MW |
481 | static int spi_dev_check(struct device *dev, void *data) |
482 | { | |
483 | struct spi_device *spi = to_spi_device(dev); | |
484 | struct spi_device *new_spi = data; | |
485 | ||
486 | if (spi->master == new_spi->master && | |
487 | spi->chip_select == new_spi->chip_select) | |
488 | return -EBUSY; | |
489 | return 0; | |
490 | } | |
491 | ||
dc87c98e GL |
492 | /** |
493 | * spi_add_device - Add spi_device allocated with spi_alloc_device | |
494 | * @spi: spi_device to register | |
495 | * | |
496 | * Companion function to spi_alloc_device. Devices allocated with | |
497 | * spi_alloc_device can be added onto the spi bus with this function. | |
498 | * | |
97d56dc6 | 499 | * Return: 0 on success; negative errno on failure |
dc87c98e GL |
500 | */ |
501 | int spi_add_device(struct spi_device *spi) | |
502 | { | |
e48880e0 | 503 | static DEFINE_MUTEX(spi_add_lock); |
74317984 JCPV |
504 | struct spi_master *master = spi->master; |
505 | struct device *dev = master->dev.parent; | |
dc87c98e GL |
506 | int status; |
507 | ||
508 | /* Chipselects are numbered 0..max; validate. */ | |
74317984 | 509 | if (spi->chip_select >= master->num_chipselect) { |
dc87c98e GL |
510 | dev_err(dev, "cs%d >= max %d\n", |
511 | spi->chip_select, | |
74317984 | 512 | master->num_chipselect); |
dc87c98e GL |
513 | return -EINVAL; |
514 | } | |
515 | ||
516 | /* Set the bus ID string */ | |
e13ac47b | 517 | spi_dev_set_name(spi); |
e48880e0 DB |
518 | |
519 | /* We need to make sure there's no other device with this | |
520 | * chipselect **BEFORE** we call setup(), else we'll trash | |
521 | * its configuration. Lock against concurrent add() calls. | |
522 | */ | |
523 | mutex_lock(&spi_add_lock); | |
524 | ||
b6fb8d3a MW |
525 | status = bus_for_each_dev(&spi_bus_type, NULL, spi, spi_dev_check); |
526 | if (status) { | |
e48880e0 DB |
527 | dev_err(dev, "chipselect %d already in use\n", |
528 | spi->chip_select); | |
e48880e0 DB |
529 | goto done; |
530 | } | |
531 | ||
74317984 JCPV |
532 | if (master->cs_gpios) |
533 | spi->cs_gpio = master->cs_gpios[spi->chip_select]; | |
534 | ||
e48880e0 DB |
535 | /* Drivers may modify this initial i/o setup, but will |
536 | * normally rely on the device being setup. Devices | |
537 | * using SPI_CS_HIGH can't coexist well otherwise... | |
538 | */ | |
7d077197 | 539 | status = spi_setup(spi); |
dc87c98e | 540 | if (status < 0) { |
eb288a1f LW |
541 | dev_err(dev, "can't setup %s, status %d\n", |
542 | dev_name(&spi->dev), status); | |
e48880e0 | 543 | goto done; |
dc87c98e GL |
544 | } |
545 | ||
e48880e0 | 546 | /* Device may be bound to an active driver when this returns */ |
dc87c98e | 547 | status = device_add(&spi->dev); |
e48880e0 | 548 | if (status < 0) |
eb288a1f LW |
549 | dev_err(dev, "can't add %s, status %d\n", |
550 | dev_name(&spi->dev), status); | |
e48880e0 | 551 | else |
35f74fca | 552 | dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev)); |
dc87c98e | 553 | |
e48880e0 DB |
554 | done: |
555 | mutex_unlock(&spi_add_lock); | |
556 | return status; | |
dc87c98e GL |
557 | } |
558 | EXPORT_SYMBOL_GPL(spi_add_device); | |
8ae12a0d | 559 | |
33e34dc6 DB |
560 | /** |
561 | * spi_new_device - instantiate one new SPI device | |
562 | * @master: Controller to which device is connected | |
563 | * @chip: Describes the SPI device | |
564 | * Context: can sleep | |
565 | * | |
566 | * On typical mainboards, this is purely internal; and it's not needed | |
8ae12a0d DB |
567 | * after board init creates the hard-wired devices. Some development |
568 | * platforms may not be able to use spi_register_board_info though, and | |
569 | * this is exported so that for example a USB or parport based adapter | |
570 | * driver could add devices (which it would learn about out-of-band). | |
082c8cb4 | 571 | * |
97d56dc6 | 572 | * Return: the new device, or NULL. |
8ae12a0d | 573 | */ |
e9d5a461 AB |
574 | struct spi_device *spi_new_device(struct spi_master *master, |
575 | struct spi_board_info *chip) | |
8ae12a0d DB |
576 | { |
577 | struct spi_device *proxy; | |
8ae12a0d DB |
578 | int status; |
579 | ||
082c8cb4 DB |
580 | /* NOTE: caller did any chip->bus_num checks necessary. |
581 | * | |
582 | * Also, unless we change the return value convention to use | |
583 | * error-or-pointer (not NULL-or-pointer), troubleshootability | |
584 | * suggests syslogged diagnostics are best here (ugh). | |
585 | */ | |
586 | ||
dc87c98e GL |
587 | proxy = spi_alloc_device(master); |
588 | if (!proxy) | |
8ae12a0d DB |
589 | return NULL; |
590 | ||
102eb975 GL |
591 | WARN_ON(strlen(chip->modalias) >= sizeof(proxy->modalias)); |
592 | ||
8ae12a0d DB |
593 | proxy->chip_select = chip->chip_select; |
594 | proxy->max_speed_hz = chip->max_speed_hz; | |
980a01c9 | 595 | proxy->mode = chip->mode; |
8ae12a0d | 596 | proxy->irq = chip->irq; |
102eb975 | 597 | strlcpy(proxy->modalias, chip->modalias, sizeof(proxy->modalias)); |
8ae12a0d DB |
598 | proxy->dev.platform_data = (void *) chip->platform_data; |
599 | proxy->controller_data = chip->controller_data; | |
600 | proxy->controller_state = NULL; | |
8ae12a0d | 601 | |
dc87c98e | 602 | status = spi_add_device(proxy); |
8ae12a0d | 603 | if (status < 0) { |
dc87c98e GL |
604 | spi_dev_put(proxy); |
605 | return NULL; | |
8ae12a0d DB |
606 | } |
607 | ||
8ae12a0d DB |
608 | return proxy; |
609 | } | |
610 | EXPORT_SYMBOL_GPL(spi_new_device); | |
611 | ||
3b1884c2 GU |
612 | /** |
613 | * spi_unregister_device - unregister a single SPI device | |
614 | * @spi: spi_device to unregister | |
615 | * | |
616 | * Start making the passed SPI device vanish. Normally this would be handled | |
617 | * by spi_unregister_master(). | |
618 | */ | |
619 | void spi_unregister_device(struct spi_device *spi) | |
620 | { | |
bd6c1644 GU |
621 | if (!spi) |
622 | return; | |
623 | ||
8324147f | 624 | if (spi->dev.of_node) { |
bd6c1644 | 625 | of_node_clear_flag(spi->dev.of_node, OF_POPULATED); |
8324147f JH |
626 | of_node_put(spi->dev.of_node); |
627 | } | |
7f24467f OP |
628 | if (ACPI_COMPANION(&spi->dev)) |
629 | acpi_device_clear_enumerated(ACPI_COMPANION(&spi->dev)); | |
bd6c1644 | 630 | device_unregister(&spi->dev); |
3b1884c2 GU |
631 | } |
632 | EXPORT_SYMBOL_GPL(spi_unregister_device); | |
633 | ||
2b9603a0 FT |
634 | static void spi_match_master_to_boardinfo(struct spi_master *master, |
635 | struct spi_board_info *bi) | |
636 | { | |
637 | struct spi_device *dev; | |
638 | ||
639 | if (master->bus_num != bi->bus_num) | |
640 | return; | |
641 | ||
642 | dev = spi_new_device(master, bi); | |
643 | if (!dev) | |
644 | dev_err(master->dev.parent, "can't create new device for %s\n", | |
645 | bi->modalias); | |
646 | } | |
647 | ||
33e34dc6 DB |
648 | /** |
649 | * spi_register_board_info - register SPI devices for a given board | |
650 | * @info: array of chip descriptors | |
651 | * @n: how many descriptors are provided | |
652 | * Context: can sleep | |
653 | * | |
8ae12a0d DB |
654 | * Board-specific early init code calls this (probably during arch_initcall) |
655 | * with segments of the SPI device table. Any device nodes are created later, | |
656 | * after the relevant parent SPI controller (bus_num) is defined. We keep | |
657 | * this table of devices forever, so that reloading a controller driver will | |
658 | * not make Linux forget about these hard-wired devices. | |
659 | * | |
660 | * Other code can also call this, e.g. a particular add-on board might provide | |
661 | * SPI devices through its expansion connector, so code initializing that board | |
662 | * would naturally declare its SPI devices. | |
663 | * | |
664 | * The board info passed can safely be __initdata ... but be careful of | |
665 | * any embedded pointers (platform_data, etc), they're copied as-is. | |
97d56dc6 JMC |
666 | * |
667 | * Return: zero on success, else a negative error code. | |
8ae12a0d | 668 | */ |
fd4a319b | 669 | int spi_register_board_info(struct spi_board_info const *info, unsigned n) |
8ae12a0d | 670 | { |
2b9603a0 FT |
671 | struct boardinfo *bi; |
672 | int i; | |
8ae12a0d | 673 | |
c7908a37 XL |
674 | if (!n) |
675 | return -EINVAL; | |
676 | ||
f9bdb7fd | 677 | bi = kcalloc(n, sizeof(*bi), GFP_KERNEL); |
8ae12a0d DB |
678 | if (!bi) |
679 | return -ENOMEM; | |
8ae12a0d | 680 | |
2b9603a0 FT |
681 | for (i = 0; i < n; i++, bi++, info++) { |
682 | struct spi_master *master; | |
8ae12a0d | 683 | |
2b9603a0 FT |
684 | memcpy(&bi->board_info, info, sizeof(*info)); |
685 | mutex_lock(&board_lock); | |
686 | list_add_tail(&bi->list, &board_list); | |
687 | list_for_each_entry(master, &spi_master_list, list) | |
688 | spi_match_master_to_boardinfo(master, &bi->board_info); | |
689 | mutex_unlock(&board_lock); | |
8ae12a0d | 690 | } |
2b9603a0 FT |
691 | |
692 | return 0; | |
8ae12a0d DB |
693 | } |
694 | ||
695 | /*-------------------------------------------------------------------------*/ | |
696 | ||
b158935f MB |
697 | static void spi_set_cs(struct spi_device *spi, bool enable) |
698 | { | |
699 | if (spi->mode & SPI_CS_HIGH) | |
700 | enable = !enable; | |
701 | ||
8eee6b9d | 702 | if (gpio_is_valid(spi->cs_gpio)) { |
b158935f | 703 | gpio_set_value(spi->cs_gpio, !enable); |
8eee6b9d TT |
704 | /* Some SPI masters need both GPIO CS & slave_select */ |
705 | if ((spi->master->flags & SPI_MASTER_GPIO_SS) && | |
706 | spi->master->set_cs) | |
707 | spi->master->set_cs(spi, !enable); | |
708 | } else if (spi->master->set_cs) { | |
b158935f | 709 | spi->master->set_cs(spi, !enable); |
8eee6b9d | 710 | } |
b158935f MB |
711 | } |
712 | ||
2de440f5 | 713 | #ifdef CONFIG_HAS_DMA |
6ad45a27 MB |
714 | static int spi_map_buf(struct spi_master *master, struct device *dev, |
715 | struct sg_table *sgt, void *buf, size_t len, | |
716 | enum dma_data_direction dir) | |
717 | { | |
718 | const bool vmalloced_buf = is_vmalloc_addr(buf); | |
df88e91b | 719 | unsigned int max_seg_size = dma_get_max_seg_size(dev); |
b1b8153c V |
720 | #ifdef CONFIG_HIGHMEM |
721 | const bool kmap_buf = ((unsigned long)buf >= PKMAP_BASE && | |
722 | (unsigned long)buf < (PKMAP_BASE + | |
723 | (LAST_PKMAP * PAGE_SIZE))); | |
724 | #else | |
725 | const bool kmap_buf = false; | |
726 | #endif | |
65598c13 AG |
727 | int desc_len; |
728 | int sgs; | |
6ad45a27 | 729 | struct page *vm_page; |
8dd4a016 | 730 | struct scatterlist *sg; |
6ad45a27 MB |
731 | void *sg_buf; |
732 | size_t min; | |
733 | int i, ret; | |
734 | ||
b1b8153c | 735 | if (vmalloced_buf || kmap_buf) { |
df88e91b | 736 | desc_len = min_t(int, max_seg_size, PAGE_SIZE); |
65598c13 | 737 | sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len); |
0569a88f | 738 | } else if (virt_addr_valid(buf)) { |
df88e91b | 739 | desc_len = min_t(int, max_seg_size, master->max_dma_len); |
65598c13 | 740 | sgs = DIV_ROUND_UP(len, desc_len); |
0569a88f V |
741 | } else { |
742 | return -EINVAL; | |
65598c13 AG |
743 | } |
744 | ||
6ad45a27 MB |
745 | ret = sg_alloc_table(sgt, sgs, GFP_KERNEL); |
746 | if (ret != 0) | |
747 | return ret; | |
748 | ||
8dd4a016 | 749 | sg = &sgt->sgl[0]; |
6ad45a27 | 750 | for (i = 0; i < sgs; i++) { |
6ad45a27 | 751 | |
b1b8153c | 752 | if (vmalloced_buf || kmap_buf) { |
65598c13 AG |
753 | min = min_t(size_t, |
754 | len, desc_len - offset_in_page(buf)); | |
b1b8153c V |
755 | if (vmalloced_buf) |
756 | vm_page = vmalloc_to_page(buf); | |
757 | else | |
758 | vm_page = kmap_to_page(buf); | |
6ad45a27 MB |
759 | if (!vm_page) { |
760 | sg_free_table(sgt); | |
761 | return -ENOMEM; | |
762 | } | |
8dd4a016 | 763 | sg_set_page(sg, vm_page, |
c1aefbdd | 764 | min, offset_in_page(buf)); |
6ad45a27 | 765 | } else { |
65598c13 | 766 | min = min_t(size_t, len, desc_len); |
6ad45a27 | 767 | sg_buf = buf; |
8dd4a016 | 768 | sg_set_buf(sg, sg_buf, min); |
6ad45a27 MB |
769 | } |
770 | ||
6ad45a27 MB |
771 | buf += min; |
772 | len -= min; | |
8dd4a016 | 773 | sg = sg_next(sg); |
6ad45a27 MB |
774 | } |
775 | ||
776 | ret = dma_map_sg(dev, sgt->sgl, sgt->nents, dir); | |
89e4b66a GU |
777 | if (!ret) |
778 | ret = -ENOMEM; | |
6ad45a27 MB |
779 | if (ret < 0) { |
780 | sg_free_table(sgt); | |
781 | return ret; | |
782 | } | |
783 | ||
784 | sgt->nents = ret; | |
785 | ||
786 | return 0; | |
787 | } | |
788 | ||
789 | static void spi_unmap_buf(struct spi_master *master, struct device *dev, | |
790 | struct sg_table *sgt, enum dma_data_direction dir) | |
791 | { | |
792 | if (sgt->orig_nents) { | |
793 | dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir); | |
794 | sg_free_table(sgt); | |
795 | } | |
796 | } | |
797 | ||
2de440f5 | 798 | static int __spi_map_msg(struct spi_master *master, struct spi_message *msg) |
99adef31 | 799 | { |
99adef31 MB |
800 | struct device *tx_dev, *rx_dev; |
801 | struct spi_transfer *xfer; | |
6ad45a27 | 802 | int ret; |
3a2eba9b | 803 | |
6ad45a27 | 804 | if (!master->can_dma) |
99adef31 MB |
805 | return 0; |
806 | ||
c37f45b5 LL |
807 | if (master->dma_tx) |
808 | tx_dev = master->dma_tx->device->dev; | |
809 | else | |
88b0aa54 | 810 | tx_dev = master->dev.parent; |
c37f45b5 LL |
811 | |
812 | if (master->dma_rx) | |
813 | rx_dev = master->dma_rx->device->dev; | |
814 | else | |
88b0aa54 | 815 | rx_dev = master->dev.parent; |
99adef31 MB |
816 | |
817 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
818 | if (!master->can_dma(master, msg->spi, xfer)) | |
819 | continue; | |
820 | ||
821 | if (xfer->tx_buf != NULL) { | |
6ad45a27 MB |
822 | ret = spi_map_buf(master, tx_dev, &xfer->tx_sg, |
823 | (void *)xfer->tx_buf, xfer->len, | |
824 | DMA_TO_DEVICE); | |
825 | if (ret != 0) | |
826 | return ret; | |
99adef31 MB |
827 | } |
828 | ||
829 | if (xfer->rx_buf != NULL) { | |
6ad45a27 MB |
830 | ret = spi_map_buf(master, rx_dev, &xfer->rx_sg, |
831 | xfer->rx_buf, xfer->len, | |
832 | DMA_FROM_DEVICE); | |
833 | if (ret != 0) { | |
834 | spi_unmap_buf(master, tx_dev, &xfer->tx_sg, | |
835 | DMA_TO_DEVICE); | |
836 | return ret; | |
99adef31 MB |
837 | } |
838 | } | |
839 | } | |
840 | ||
841 | master->cur_msg_mapped = true; | |
842 | ||
843 | return 0; | |
844 | } | |
845 | ||
4b786458 | 846 | static int __spi_unmap_msg(struct spi_master *master, struct spi_message *msg) |
99adef31 MB |
847 | { |
848 | struct spi_transfer *xfer; | |
849 | struct device *tx_dev, *rx_dev; | |
850 | ||
6ad45a27 | 851 | if (!master->cur_msg_mapped || !master->can_dma) |
99adef31 MB |
852 | return 0; |
853 | ||
c37f45b5 LL |
854 | if (master->dma_tx) |
855 | tx_dev = master->dma_tx->device->dev; | |
856 | else | |
88b0aa54 | 857 | tx_dev = master->dev.parent; |
c37f45b5 LL |
858 | |
859 | if (master->dma_rx) | |
860 | rx_dev = master->dma_rx->device->dev; | |
861 | else | |
88b0aa54 | 862 | rx_dev = master->dev.parent; |
99adef31 MB |
863 | |
864 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
865 | if (!master->can_dma(master, msg->spi, xfer)) | |
866 | continue; | |
867 | ||
6ad45a27 MB |
868 | spi_unmap_buf(master, rx_dev, &xfer->rx_sg, DMA_FROM_DEVICE); |
869 | spi_unmap_buf(master, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE); | |
99adef31 MB |
870 | } |
871 | ||
872 | return 0; | |
873 | } | |
2de440f5 | 874 | #else /* !CONFIG_HAS_DMA */ |
f4502dd1 V |
875 | static inline int spi_map_buf(struct spi_master *master, |
876 | struct device *dev, struct sg_table *sgt, | |
877 | void *buf, size_t len, | |
878 | enum dma_data_direction dir) | |
879 | { | |
880 | return -EINVAL; | |
881 | } | |
882 | ||
883 | static inline void spi_unmap_buf(struct spi_master *master, | |
884 | struct device *dev, struct sg_table *sgt, | |
885 | enum dma_data_direction dir) | |
886 | { | |
887 | } | |
888 | ||
2de440f5 GU |
889 | static inline int __spi_map_msg(struct spi_master *master, |
890 | struct spi_message *msg) | |
891 | { | |
892 | return 0; | |
893 | } | |
894 | ||
4b786458 MS |
895 | static inline int __spi_unmap_msg(struct spi_master *master, |
896 | struct spi_message *msg) | |
2de440f5 GU |
897 | { |
898 | return 0; | |
899 | } | |
900 | #endif /* !CONFIG_HAS_DMA */ | |
901 | ||
4b786458 MS |
902 | static inline int spi_unmap_msg(struct spi_master *master, |
903 | struct spi_message *msg) | |
904 | { | |
905 | struct spi_transfer *xfer; | |
906 | ||
907 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
908 | /* | |
909 | * Restore the original value of tx_buf or rx_buf if they are | |
910 | * NULL. | |
911 | */ | |
912 | if (xfer->tx_buf == master->dummy_tx) | |
913 | xfer->tx_buf = NULL; | |
914 | if (xfer->rx_buf == master->dummy_rx) | |
915 | xfer->rx_buf = NULL; | |
916 | } | |
917 | ||
918 | return __spi_unmap_msg(master, msg); | |
919 | } | |
920 | ||
2de440f5 GU |
921 | static int spi_map_msg(struct spi_master *master, struct spi_message *msg) |
922 | { | |
923 | struct spi_transfer *xfer; | |
924 | void *tmp; | |
925 | unsigned int max_tx, max_rx; | |
926 | ||
927 | if (master->flags & (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX)) { | |
928 | max_tx = 0; | |
929 | max_rx = 0; | |
930 | ||
931 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
932 | if ((master->flags & SPI_MASTER_MUST_TX) && | |
933 | !xfer->tx_buf) | |
934 | max_tx = max(xfer->len, max_tx); | |
935 | if ((master->flags & SPI_MASTER_MUST_RX) && | |
936 | !xfer->rx_buf) | |
937 | max_rx = max(xfer->len, max_rx); | |
938 | } | |
939 | ||
940 | if (max_tx) { | |
941 | tmp = krealloc(master->dummy_tx, max_tx, | |
942 | GFP_KERNEL | GFP_DMA); | |
943 | if (!tmp) | |
944 | return -ENOMEM; | |
945 | master->dummy_tx = tmp; | |
946 | memset(tmp, 0, max_tx); | |
947 | } | |
948 | ||
949 | if (max_rx) { | |
950 | tmp = krealloc(master->dummy_rx, max_rx, | |
951 | GFP_KERNEL | GFP_DMA); | |
952 | if (!tmp) | |
953 | return -ENOMEM; | |
954 | master->dummy_rx = tmp; | |
955 | } | |
956 | ||
957 | if (max_tx || max_rx) { | |
958 | list_for_each_entry(xfer, &msg->transfers, | |
959 | transfer_list) { | |
960 | if (!xfer->tx_buf) | |
961 | xfer->tx_buf = master->dummy_tx; | |
962 | if (!xfer->rx_buf) | |
963 | xfer->rx_buf = master->dummy_rx; | |
964 | } | |
965 | } | |
966 | } | |
967 | ||
968 | return __spi_map_msg(master, msg); | |
969 | } | |
99adef31 | 970 | |
b158935f MB |
971 | /* |
972 | * spi_transfer_one_message - Default implementation of transfer_one_message() | |
973 | * | |
974 | * This is a standard implementation of transfer_one_message() for | |
8ba811a7 | 975 | * drivers which implement a transfer_one() operation. It provides |
b158935f MB |
976 | * standard handling of delays and chip select management. |
977 | */ | |
978 | static int spi_transfer_one_message(struct spi_master *master, | |
979 | struct spi_message *msg) | |
980 | { | |
981 | struct spi_transfer *xfer; | |
b158935f MB |
982 | bool keep_cs = false; |
983 | int ret = 0; | |
d0716dde | 984 | unsigned long long ms = 1; |
eca2ebc7 MS |
985 | struct spi_statistics *statm = &master->statistics; |
986 | struct spi_statistics *stats = &msg->spi->statistics; | |
b158935f MB |
987 | |
988 | spi_set_cs(msg->spi, true); | |
989 | ||
eca2ebc7 MS |
990 | SPI_STATISTICS_INCREMENT_FIELD(statm, messages); |
991 | SPI_STATISTICS_INCREMENT_FIELD(stats, messages); | |
992 | ||
b158935f MB |
993 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { |
994 | trace_spi_transfer_start(msg, xfer); | |
995 | ||
eca2ebc7 MS |
996 | spi_statistics_add_transfer_stats(statm, xfer, master); |
997 | spi_statistics_add_transfer_stats(stats, xfer, master); | |
998 | ||
38ec10f6 MB |
999 | if (xfer->tx_buf || xfer->rx_buf) { |
1000 | reinit_completion(&master->xfer_completion); | |
b158935f | 1001 | |
38ec10f6 MB |
1002 | ret = master->transfer_one(master, msg->spi, xfer); |
1003 | if (ret < 0) { | |
eca2ebc7 MS |
1004 | SPI_STATISTICS_INCREMENT_FIELD(statm, |
1005 | errors); | |
1006 | SPI_STATISTICS_INCREMENT_FIELD(stats, | |
1007 | errors); | |
38ec10f6 MB |
1008 | dev_err(&msg->spi->dev, |
1009 | "SPI transfer failed: %d\n", ret); | |
1010 | goto out; | |
1011 | } | |
b158935f | 1012 | |
38ec10f6 MB |
1013 | if (ret > 0) { |
1014 | ret = 0; | |
d0716dde SW |
1015 | ms = 8LL * 1000LL * xfer->len; |
1016 | do_div(ms, xfer->speed_hz); | |
38ec10f6 | 1017 | ms += ms + 100; /* some tolerance */ |
16a0ce4e | 1018 | |
d0716dde SW |
1019 | if (ms > UINT_MAX) |
1020 | ms = UINT_MAX; | |
1021 | ||
38ec10f6 MB |
1022 | ms = wait_for_completion_timeout(&master->xfer_completion, |
1023 | msecs_to_jiffies(ms)); | |
1024 | } | |
16a0ce4e | 1025 | |
38ec10f6 | 1026 | if (ms == 0) { |
eca2ebc7 MS |
1027 | SPI_STATISTICS_INCREMENT_FIELD(statm, |
1028 | timedout); | |
1029 | SPI_STATISTICS_INCREMENT_FIELD(stats, | |
1030 | timedout); | |
38ec10f6 MB |
1031 | dev_err(&msg->spi->dev, |
1032 | "SPI transfer timed out\n"); | |
1033 | msg->status = -ETIMEDOUT; | |
1034 | } | |
1035 | } else { | |
1036 | if (xfer->len) | |
1037 | dev_err(&msg->spi->dev, | |
1038 | "Bufferless transfer has length %u\n", | |
1039 | xfer->len); | |
13a42798 | 1040 | } |
b158935f MB |
1041 | |
1042 | trace_spi_transfer_stop(msg, xfer); | |
1043 | ||
1044 | if (msg->status != -EINPROGRESS) | |
1045 | goto out; | |
1046 | ||
8244bd3a DK |
1047 | if (xfer->delay_usecs) { |
1048 | u16 us = xfer->delay_usecs; | |
1049 | ||
1050 | if (us <= 10) | |
1051 | udelay(us); | |
1052 | else | |
1053 | usleep_range(us, us + DIV_ROUND_UP(us, 10)); | |
1054 | } | |
b158935f MB |
1055 | |
1056 | if (xfer->cs_change) { | |
1057 | if (list_is_last(&xfer->transfer_list, | |
1058 | &msg->transfers)) { | |
1059 | keep_cs = true; | |
1060 | } else { | |
0b73aa63 MB |
1061 | spi_set_cs(msg->spi, false); |
1062 | udelay(10); | |
1063 | spi_set_cs(msg->spi, true); | |
b158935f MB |
1064 | } |
1065 | } | |
1066 | ||
1067 | msg->actual_length += xfer->len; | |
1068 | } | |
1069 | ||
1070 | out: | |
1071 | if (ret != 0 || !keep_cs) | |
1072 | spi_set_cs(msg->spi, false); | |
1073 | ||
1074 | if (msg->status == -EINPROGRESS) | |
1075 | msg->status = ret; | |
1076 | ||
ff61eb42 | 1077 | if (msg->status && master->handle_err) |
b716c4ff AS |
1078 | master->handle_err(master, msg); |
1079 | ||
d780c371 MS |
1080 | spi_res_release(master, msg); |
1081 | ||
b158935f MB |
1082 | spi_finalize_current_message(master); |
1083 | ||
1084 | return ret; | |
1085 | } | |
1086 | ||
1087 | /** | |
1088 | * spi_finalize_current_transfer - report completion of a transfer | |
2c675689 | 1089 | * @master: the master reporting completion |
b158935f MB |
1090 | * |
1091 | * Called by SPI drivers using the core transfer_one_message() | |
1092 | * implementation to notify it that the current interrupt driven | |
9e8f4882 | 1093 | * transfer has finished and the next one may be scheduled. |
b158935f MB |
1094 | */ |
1095 | void spi_finalize_current_transfer(struct spi_master *master) | |
1096 | { | |
1097 | complete(&master->xfer_completion); | |
1098 | } | |
1099 | EXPORT_SYMBOL_GPL(spi_finalize_current_transfer); | |
1100 | ||
ffbbdd21 | 1101 | /** |
fc9e0f71 MB |
1102 | * __spi_pump_messages - function which processes spi message queue |
1103 | * @master: master to process queue for | |
1104 | * @in_kthread: true if we are in the context of the message pump thread | |
ffbbdd21 LW |
1105 | * |
1106 | * This function checks if there is any spi message in the queue that | |
1107 | * needs processing and if so call out to the driver to initialize hardware | |
1108 | * and transfer each message. | |
1109 | * | |
0461a414 MB |
1110 | * Note that it is called both from the kthread itself and also from |
1111 | * inside spi_sync(); the queue extraction handling at the top of the | |
1112 | * function should deal with this safely. | |
ffbbdd21 | 1113 | */ |
ef4d96ec | 1114 | static void __spi_pump_messages(struct spi_master *master, bool in_kthread) |
ffbbdd21 | 1115 | { |
ffbbdd21 LW |
1116 | unsigned long flags; |
1117 | bool was_busy = false; | |
1118 | int ret; | |
1119 | ||
983aee5d | 1120 | /* Lock queue */ |
ffbbdd21 | 1121 | spin_lock_irqsave(&master->queue_lock, flags); |
983aee5d MB |
1122 | |
1123 | /* Make sure we are not already running a message */ | |
1124 | if (master->cur_msg) { | |
1125 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1126 | return; | |
1127 | } | |
1128 | ||
0461a414 MB |
1129 | /* If another context is idling the device then defer */ |
1130 | if (master->idling) { | |
3989144f | 1131 | kthread_queue_work(&master->kworker, &master->pump_messages); |
0461a414 MB |
1132 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1133 | return; | |
1134 | } | |
1135 | ||
983aee5d | 1136 | /* Check if the queue is idle */ |
ffbbdd21 | 1137 | if (list_empty(&master->queue) || !master->running) { |
b0b36b86 BF |
1138 | if (!master->busy) { |
1139 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1140 | return; | |
ffbbdd21 | 1141 | } |
fc9e0f71 MB |
1142 | |
1143 | /* Only do teardown in the thread */ | |
1144 | if (!in_kthread) { | |
3989144f | 1145 | kthread_queue_work(&master->kworker, |
fc9e0f71 MB |
1146 | &master->pump_messages); |
1147 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1148 | return; | |
1149 | } | |
1150 | ||
ffbbdd21 | 1151 | master->busy = false; |
0461a414 | 1152 | master->idling = true; |
ffbbdd21 | 1153 | spin_unlock_irqrestore(&master->queue_lock, flags); |
0461a414 | 1154 | |
3a2eba9b MB |
1155 | kfree(master->dummy_rx); |
1156 | master->dummy_rx = NULL; | |
1157 | kfree(master->dummy_tx); | |
1158 | master->dummy_tx = NULL; | |
b0b36b86 BF |
1159 | if (master->unprepare_transfer_hardware && |
1160 | master->unprepare_transfer_hardware(master)) | |
1161 | dev_err(&master->dev, | |
1162 | "failed to unprepare transfer hardware\n"); | |
49834de2 MB |
1163 | if (master->auto_runtime_pm) { |
1164 | pm_runtime_mark_last_busy(master->dev.parent); | |
1165 | pm_runtime_put_autosuspend(master->dev.parent); | |
1166 | } | |
56ec1978 | 1167 | trace_spi_master_idle(master); |
ffbbdd21 | 1168 | |
0461a414 MB |
1169 | spin_lock_irqsave(&master->queue_lock, flags); |
1170 | master->idling = false; | |
ffbbdd21 LW |
1171 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1172 | return; | |
1173 | } | |
ffbbdd21 | 1174 | |
ffbbdd21 LW |
1175 | /* Extract head of queue */ |
1176 | master->cur_msg = | |
a89e2d27 | 1177 | list_first_entry(&master->queue, struct spi_message, queue); |
ffbbdd21 LW |
1178 | |
1179 | list_del_init(&master->cur_msg->queue); | |
1180 | if (master->busy) | |
1181 | was_busy = true; | |
1182 | else | |
1183 | master->busy = true; | |
1184 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1185 | ||
ef4d96ec MB |
1186 | mutex_lock(&master->io_mutex); |
1187 | ||
49834de2 MB |
1188 | if (!was_busy && master->auto_runtime_pm) { |
1189 | ret = pm_runtime_get_sync(master->dev.parent); | |
1190 | if (ret < 0) { | |
1191 | dev_err(&master->dev, "Failed to power device: %d\n", | |
1192 | ret); | |
764f2166 | 1193 | mutex_unlock(&master->io_mutex); |
49834de2 MB |
1194 | return; |
1195 | } | |
1196 | } | |
1197 | ||
56ec1978 MB |
1198 | if (!was_busy) |
1199 | trace_spi_master_busy(master); | |
1200 | ||
7dfd2bd7 | 1201 | if (!was_busy && master->prepare_transfer_hardware) { |
ffbbdd21 LW |
1202 | ret = master->prepare_transfer_hardware(master); |
1203 | if (ret) { | |
1204 | dev_err(&master->dev, | |
1205 | "failed to prepare transfer hardware\n"); | |
49834de2 MB |
1206 | |
1207 | if (master->auto_runtime_pm) | |
1208 | pm_runtime_put(master->dev.parent); | |
764f2166 | 1209 | mutex_unlock(&master->io_mutex); |
ffbbdd21 LW |
1210 | return; |
1211 | } | |
1212 | } | |
1213 | ||
56ec1978 MB |
1214 | trace_spi_message_start(master->cur_msg); |
1215 | ||
2841a5fc MB |
1216 | if (master->prepare_message) { |
1217 | ret = master->prepare_message(master, master->cur_msg); | |
1218 | if (ret) { | |
1219 | dev_err(&master->dev, | |
1220 | "failed to prepare message: %d\n", ret); | |
1221 | master->cur_msg->status = ret; | |
1222 | spi_finalize_current_message(master); | |
49023d2e | 1223 | goto out; |
2841a5fc MB |
1224 | } |
1225 | master->cur_msg_prepared = true; | |
1226 | } | |
1227 | ||
99adef31 MB |
1228 | ret = spi_map_msg(master, master->cur_msg); |
1229 | if (ret) { | |
1230 | master->cur_msg->status = ret; | |
1231 | spi_finalize_current_message(master); | |
49023d2e | 1232 | goto out; |
99adef31 MB |
1233 | } |
1234 | ||
ffbbdd21 LW |
1235 | ret = master->transfer_one_message(master, master->cur_msg); |
1236 | if (ret) { | |
1237 | dev_err(&master->dev, | |
1f802f82 | 1238 | "failed to transfer one message from queue\n"); |
49023d2e | 1239 | goto out; |
ffbbdd21 | 1240 | } |
49023d2e JH |
1241 | |
1242 | out: | |
ef4d96ec | 1243 | mutex_unlock(&master->io_mutex); |
62826970 MB |
1244 | |
1245 | /* Prod the scheduler in case transfer_one() was busy waiting */ | |
49023d2e JH |
1246 | if (!ret) |
1247 | cond_resched(); | |
ffbbdd21 LW |
1248 | } |
1249 | ||
fc9e0f71 MB |
1250 | /** |
1251 | * spi_pump_messages - kthread work function which processes spi message queue | |
1252 | * @work: pointer to kthread work struct contained in the master struct | |
1253 | */ | |
1254 | static void spi_pump_messages(struct kthread_work *work) | |
1255 | { | |
1256 | struct spi_master *master = | |
1257 | container_of(work, struct spi_master, pump_messages); | |
1258 | ||
ef4d96ec | 1259 | __spi_pump_messages(master, true); |
fc9e0f71 MB |
1260 | } |
1261 | ||
ffbbdd21 LW |
1262 | static int spi_init_queue(struct spi_master *master) |
1263 | { | |
1264 | struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; | |
1265 | ||
ffbbdd21 LW |
1266 | master->running = false; |
1267 | master->busy = false; | |
1268 | ||
3989144f | 1269 | kthread_init_worker(&master->kworker); |
ffbbdd21 | 1270 | master->kworker_task = kthread_run(kthread_worker_fn, |
f170168b | 1271 | &master->kworker, "%s", |
ffbbdd21 LW |
1272 | dev_name(&master->dev)); |
1273 | if (IS_ERR(master->kworker_task)) { | |
1274 | dev_err(&master->dev, "failed to create message pump task\n"); | |
98a8f5a0 | 1275 | return PTR_ERR(master->kworker_task); |
ffbbdd21 | 1276 | } |
3989144f | 1277 | kthread_init_work(&master->pump_messages, spi_pump_messages); |
ffbbdd21 LW |
1278 | |
1279 | /* | |
1280 | * Master config will indicate if this controller should run the | |
1281 | * message pump with high (realtime) priority to reduce the transfer | |
1282 | * latency on the bus by minimising the delay between a transfer | |
1283 | * request and the scheduling of the message pump thread. Without this | |
1284 | * setting the message pump thread will remain at default priority. | |
1285 | */ | |
1286 | if (master->rt) { | |
1287 | dev_info(&master->dev, | |
1288 | "will run message pump with realtime priority\n"); | |
1289 | sched_setscheduler(master->kworker_task, SCHED_FIFO, ¶m); | |
1290 | } | |
1291 | ||
1292 | return 0; | |
1293 | } | |
1294 | ||
1295 | /** | |
1296 | * spi_get_next_queued_message() - called by driver to check for queued | |
1297 | * messages | |
1298 | * @master: the master to check for queued messages | |
1299 | * | |
1300 | * If there are more messages in the queue, the next message is returned from | |
1301 | * this call. | |
97d56dc6 JMC |
1302 | * |
1303 | * Return: the next message in the queue, else NULL if the queue is empty. | |
ffbbdd21 LW |
1304 | */ |
1305 | struct spi_message *spi_get_next_queued_message(struct spi_master *master) | |
1306 | { | |
1307 | struct spi_message *next; | |
1308 | unsigned long flags; | |
1309 | ||
1310 | /* get a pointer to the next message, if any */ | |
1311 | spin_lock_irqsave(&master->queue_lock, flags); | |
1cfd97f9 AL |
1312 | next = list_first_entry_or_null(&master->queue, struct spi_message, |
1313 | queue); | |
ffbbdd21 LW |
1314 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1315 | ||
1316 | return next; | |
1317 | } | |
1318 | EXPORT_SYMBOL_GPL(spi_get_next_queued_message); | |
1319 | ||
1320 | /** | |
1321 | * spi_finalize_current_message() - the current message is complete | |
1322 | * @master: the master to return the message to | |
1323 | * | |
1324 | * Called by the driver to notify the core that the message in the front of the | |
1325 | * queue is complete and can be removed from the queue. | |
1326 | */ | |
1327 | void spi_finalize_current_message(struct spi_master *master) | |
1328 | { | |
1329 | struct spi_message *mesg; | |
1330 | unsigned long flags; | |
2841a5fc | 1331 | int ret; |
ffbbdd21 LW |
1332 | |
1333 | spin_lock_irqsave(&master->queue_lock, flags); | |
1334 | mesg = master->cur_msg; | |
ffbbdd21 LW |
1335 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1336 | ||
99adef31 MB |
1337 | spi_unmap_msg(master, mesg); |
1338 | ||
2841a5fc MB |
1339 | if (master->cur_msg_prepared && master->unprepare_message) { |
1340 | ret = master->unprepare_message(master, mesg); | |
1341 | if (ret) { | |
1342 | dev_err(&master->dev, | |
1343 | "failed to unprepare message: %d\n", ret); | |
1344 | } | |
1345 | } | |
391949b6 | 1346 | |
8e76ef88 MS |
1347 | spin_lock_irqsave(&master->queue_lock, flags); |
1348 | master->cur_msg = NULL; | |
2841a5fc | 1349 | master->cur_msg_prepared = false; |
3989144f | 1350 | kthread_queue_work(&master->kworker, &master->pump_messages); |
8e76ef88 MS |
1351 | spin_unlock_irqrestore(&master->queue_lock, flags); |
1352 | ||
1353 | trace_spi_message_done(mesg); | |
2841a5fc | 1354 | |
ffbbdd21 LW |
1355 | mesg->state = NULL; |
1356 | if (mesg->complete) | |
1357 | mesg->complete(mesg->context); | |
1358 | } | |
1359 | EXPORT_SYMBOL_GPL(spi_finalize_current_message); | |
1360 | ||
1361 | static int spi_start_queue(struct spi_master *master) | |
1362 | { | |
1363 | unsigned long flags; | |
1364 | ||
1365 | spin_lock_irqsave(&master->queue_lock, flags); | |
1366 | ||
1367 | if (master->running || master->busy) { | |
1368 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1369 | return -EBUSY; | |
1370 | } | |
1371 | ||
1372 | master->running = true; | |
1373 | master->cur_msg = NULL; | |
1374 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1375 | ||
3989144f | 1376 | kthread_queue_work(&master->kworker, &master->pump_messages); |
ffbbdd21 LW |
1377 | |
1378 | return 0; | |
1379 | } | |
1380 | ||
1381 | static int spi_stop_queue(struct spi_master *master) | |
1382 | { | |
1383 | unsigned long flags; | |
1384 | unsigned limit = 500; | |
1385 | int ret = 0; | |
1386 | ||
1387 | spin_lock_irqsave(&master->queue_lock, flags); | |
1388 | ||
1389 | /* | |
1390 | * This is a bit lame, but is optimized for the common execution path. | |
1391 | * A wait_queue on the master->busy could be used, but then the common | |
1392 | * execution path (pump_messages) would be required to call wake_up or | |
1393 | * friends on every SPI message. Do this instead. | |
1394 | */ | |
1395 | while ((!list_empty(&master->queue) || master->busy) && limit--) { | |
1396 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
f97b26b0 | 1397 | usleep_range(10000, 11000); |
ffbbdd21 LW |
1398 | spin_lock_irqsave(&master->queue_lock, flags); |
1399 | } | |
1400 | ||
1401 | if (!list_empty(&master->queue) || master->busy) | |
1402 | ret = -EBUSY; | |
1403 | else | |
1404 | master->running = false; | |
1405 | ||
1406 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1407 | ||
1408 | if (ret) { | |
1409 | dev_warn(&master->dev, | |
1410 | "could not stop message queue\n"); | |
1411 | return ret; | |
1412 | } | |
1413 | return ret; | |
1414 | } | |
1415 | ||
1416 | static int spi_destroy_queue(struct spi_master *master) | |
1417 | { | |
1418 | int ret; | |
1419 | ||
1420 | ret = spi_stop_queue(master); | |
1421 | ||
1422 | /* | |
3989144f | 1423 | * kthread_flush_worker will block until all work is done. |
ffbbdd21 LW |
1424 | * If the reason that stop_queue timed out is that the work will never |
1425 | * finish, then it does no good to call flush/stop thread, so | |
1426 | * return anyway. | |
1427 | */ | |
1428 | if (ret) { | |
1429 | dev_err(&master->dev, "problem destroying queue\n"); | |
1430 | return ret; | |
1431 | } | |
1432 | ||
3989144f | 1433 | kthread_flush_worker(&master->kworker); |
ffbbdd21 LW |
1434 | kthread_stop(master->kworker_task); |
1435 | ||
1436 | return 0; | |
1437 | } | |
1438 | ||
0461a414 MB |
1439 | static int __spi_queued_transfer(struct spi_device *spi, |
1440 | struct spi_message *msg, | |
1441 | bool need_pump) | |
ffbbdd21 LW |
1442 | { |
1443 | struct spi_master *master = spi->master; | |
1444 | unsigned long flags; | |
1445 | ||
1446 | spin_lock_irqsave(&master->queue_lock, flags); | |
1447 | ||
1448 | if (!master->running) { | |
1449 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1450 | return -ESHUTDOWN; | |
1451 | } | |
1452 | msg->actual_length = 0; | |
1453 | msg->status = -EINPROGRESS; | |
1454 | ||
1455 | list_add_tail(&msg->queue, &master->queue); | |
0461a414 | 1456 | if (!master->busy && need_pump) |
3989144f | 1457 | kthread_queue_work(&master->kworker, &master->pump_messages); |
ffbbdd21 LW |
1458 | |
1459 | spin_unlock_irqrestore(&master->queue_lock, flags); | |
1460 | return 0; | |
1461 | } | |
1462 | ||
0461a414 MB |
1463 | /** |
1464 | * spi_queued_transfer - transfer function for queued transfers | |
1465 | * @spi: spi device which is requesting transfer | |
1466 | * @msg: spi message which is to handled is queued to driver queue | |
97d56dc6 JMC |
1467 | * |
1468 | * Return: zero on success, else a negative error code. | |
0461a414 MB |
1469 | */ |
1470 | static int spi_queued_transfer(struct spi_device *spi, struct spi_message *msg) | |
1471 | { | |
1472 | return __spi_queued_transfer(spi, msg, true); | |
1473 | } | |
1474 | ||
ffbbdd21 LW |
1475 | static int spi_master_initialize_queue(struct spi_master *master) |
1476 | { | |
1477 | int ret; | |
1478 | ||
ffbbdd21 | 1479 | master->transfer = spi_queued_transfer; |
b158935f MB |
1480 | if (!master->transfer_one_message) |
1481 | master->transfer_one_message = spi_transfer_one_message; | |
ffbbdd21 LW |
1482 | |
1483 | /* Initialize and start queue */ | |
1484 | ret = spi_init_queue(master); | |
1485 | if (ret) { | |
1486 | dev_err(&master->dev, "problem initializing queue\n"); | |
1487 | goto err_init_queue; | |
1488 | } | |
c3676d5c | 1489 | master->queued = true; |
ffbbdd21 LW |
1490 | ret = spi_start_queue(master); |
1491 | if (ret) { | |
1492 | dev_err(&master->dev, "problem starting queue\n"); | |
1493 | goto err_start_queue; | |
1494 | } | |
1495 | ||
1496 | return 0; | |
1497 | ||
1498 | err_start_queue: | |
ffbbdd21 | 1499 | spi_destroy_queue(master); |
c3676d5c | 1500 | err_init_queue: |
ffbbdd21 LW |
1501 | return ret; |
1502 | } | |
1503 | ||
1504 | /*-------------------------------------------------------------------------*/ | |
1505 | ||
7cb94361 | 1506 | #if defined(CONFIG_OF) |
c2e51ac3 GU |
1507 | static int of_spi_parse_dt(struct spi_master *master, struct spi_device *spi, |
1508 | struct device_node *nc) | |
aff5e3f8 | 1509 | { |
aff5e3f8 | 1510 | u32 value; |
c2e51ac3 | 1511 | int rc; |
aff5e3f8 PA |
1512 | |
1513 | /* Device address */ | |
1514 | rc = of_property_read_u32(nc, "reg", &value); | |
1515 | if (rc) { | |
1516 | dev_err(&master->dev, "%s has no valid 'reg' property (%d)\n", | |
1517 | nc->full_name, rc); | |
c2e51ac3 | 1518 | return rc; |
aff5e3f8 PA |
1519 | } |
1520 | spi->chip_select = value; | |
1521 | ||
1522 | /* Mode (clock phase/polarity/etc.) */ | |
1523 | if (of_find_property(nc, "spi-cpha", NULL)) | |
1524 | spi->mode |= SPI_CPHA; | |
1525 | if (of_find_property(nc, "spi-cpol", NULL)) | |
1526 | spi->mode |= SPI_CPOL; | |
1527 | if (of_find_property(nc, "spi-cs-high", NULL)) | |
1528 | spi->mode |= SPI_CS_HIGH; | |
1529 | if (of_find_property(nc, "spi-3wire", NULL)) | |
1530 | spi->mode |= SPI_3WIRE; | |
1531 | if (of_find_property(nc, "spi-lsb-first", NULL)) | |
1532 | spi->mode |= SPI_LSB_FIRST; | |
1533 | ||
1534 | /* Device DUAL/QUAD mode */ | |
1535 | if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) { | |
1536 | switch (value) { | |
1537 | case 1: | |
1538 | break; | |
1539 | case 2: | |
1540 | spi->mode |= SPI_TX_DUAL; | |
1541 | break; | |
1542 | case 4: | |
1543 | spi->mode |= SPI_TX_QUAD; | |
1544 | break; | |
1545 | default: | |
1546 | dev_warn(&master->dev, | |
1547 | "spi-tx-bus-width %d not supported\n", | |
1548 | value); | |
1549 | break; | |
1550 | } | |
1551 | } | |
1552 | ||
1553 | if (!of_property_read_u32(nc, "spi-rx-bus-width", &value)) { | |
1554 | switch (value) { | |
1555 | case 1: | |
1556 | break; | |
1557 | case 2: | |
1558 | spi->mode |= SPI_RX_DUAL; | |
1559 | break; | |
1560 | case 4: | |
1561 | spi->mode |= SPI_RX_QUAD; | |
1562 | break; | |
1563 | default: | |
1564 | dev_warn(&master->dev, | |
1565 | "spi-rx-bus-width %d not supported\n", | |
1566 | value); | |
1567 | break; | |
1568 | } | |
1569 | } | |
1570 | ||
1571 | /* Device speed */ | |
1572 | rc = of_property_read_u32(nc, "spi-max-frequency", &value); | |
1573 | if (rc) { | |
1574 | dev_err(&master->dev, "%s has no valid 'spi-max-frequency' property (%d)\n", | |
1575 | nc->full_name, rc); | |
c2e51ac3 | 1576 | return rc; |
aff5e3f8 PA |
1577 | } |
1578 | spi->max_speed_hz = value; | |
1579 | ||
c2e51ac3 GU |
1580 | return 0; |
1581 | } | |
1582 | ||
1583 | static struct spi_device * | |
1584 | of_register_spi_device(struct spi_master *master, struct device_node *nc) | |
1585 | { | |
1586 | struct spi_device *spi; | |
1587 | int rc; | |
1588 | ||
1589 | /* Alloc an spi_device */ | |
1590 | spi = spi_alloc_device(master); | |
1591 | if (!spi) { | |
1592 | dev_err(&master->dev, "spi_device alloc error for %s\n", | |
1593 | nc->full_name); | |
1594 | rc = -ENOMEM; | |
1595 | goto err_out; | |
1596 | } | |
1597 | ||
1598 | /* Select device driver */ | |
1599 | rc = of_modalias_node(nc, spi->modalias, | |
1600 | sizeof(spi->modalias)); | |
1601 | if (rc < 0) { | |
1602 | dev_err(&master->dev, "cannot find modalias for %s\n", | |
1603 | nc->full_name); | |
1604 | goto err_out; | |
1605 | } | |
1606 | ||
1607 | rc = of_spi_parse_dt(master, spi, nc); | |
1608 | if (rc) | |
1609 | goto err_out; | |
1610 | ||
aff5e3f8 PA |
1611 | /* Store a pointer to the node in the device structure */ |
1612 | of_node_get(nc); | |
1613 | spi->dev.of_node = nc; | |
1614 | ||
1615 | /* Register the new device */ | |
aff5e3f8 PA |
1616 | rc = spi_add_device(spi); |
1617 | if (rc) { | |
1618 | dev_err(&master->dev, "spi_device register error %s\n", | |
1619 | nc->full_name); | |
8324147f | 1620 | goto err_of_node_put; |
aff5e3f8 PA |
1621 | } |
1622 | ||
1623 | return spi; | |
1624 | ||
8324147f JH |
1625 | err_of_node_put: |
1626 | of_node_put(nc); | |
aff5e3f8 PA |
1627 | err_out: |
1628 | spi_dev_put(spi); | |
1629 | return ERR_PTR(rc); | |
1630 | } | |
1631 | ||
d57a4282 GL |
1632 | /** |
1633 | * of_register_spi_devices() - Register child devices onto the SPI bus | |
1634 | * @master: Pointer to spi_master device | |
1635 | * | |
1636 | * Registers an spi_device for each child node of master node which has a 'reg' | |
1637 | * property. | |
1638 | */ | |
1639 | static void of_register_spi_devices(struct spi_master *master) | |
1640 | { | |
1641 | struct spi_device *spi; | |
1642 | struct device_node *nc; | |
d57a4282 GL |
1643 | |
1644 | if (!master->dev.of_node) | |
1645 | return; | |
1646 | ||
f3b6159e | 1647 | for_each_available_child_of_node(master->dev.of_node, nc) { |
bd6c1644 GU |
1648 | if (of_node_test_and_set_flag(nc, OF_POPULATED)) |
1649 | continue; | |
aff5e3f8 | 1650 | spi = of_register_spi_device(master, nc); |
e0af98a7 | 1651 | if (IS_ERR(spi)) { |
aff5e3f8 | 1652 | dev_warn(&master->dev, "Failed to create SPI device for %s\n", |
d57a4282 | 1653 | nc->full_name); |
e0af98a7 RR |
1654 | of_node_clear_flag(nc, OF_POPULATED); |
1655 | } | |
d57a4282 GL |
1656 | } |
1657 | } | |
1658 | #else | |
1659 | static void of_register_spi_devices(struct spi_master *master) { } | |
1660 | #endif | |
1661 | ||
64bee4d2 MW |
1662 | #ifdef CONFIG_ACPI |
1663 | static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) | |
1664 | { | |
1665 | struct spi_device *spi = data; | |
a0a90718 | 1666 | struct spi_master *master = spi->master; |
64bee4d2 MW |
1667 | |
1668 | if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) { | |
1669 | struct acpi_resource_spi_serialbus *sb; | |
1670 | ||
1671 | sb = &ares->data.spi_serial_bus; | |
1672 | if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { | |
a0a90718 MW |
1673 | /* |
1674 | * ACPI DeviceSelection numbering is handled by the | |
1675 | * host controller driver in Windows and can vary | |
1676 | * from driver to driver. In Linux we always expect | |
1677 | * 0 .. max - 1 so we need to ask the driver to | |
1678 | * translate between the two schemes. | |
1679 | */ | |
1680 | if (master->fw_translate_cs) { | |
1681 | int cs = master->fw_translate_cs(master, | |
1682 | sb->device_selection); | |
1683 | if (cs < 0) | |
1684 | return cs; | |
1685 | spi->chip_select = cs; | |
1686 | } else { | |
1687 | spi->chip_select = sb->device_selection; | |
1688 | } | |
1689 | ||
64bee4d2 MW |
1690 | spi->max_speed_hz = sb->connection_speed; |
1691 | ||
1692 | if (sb->clock_phase == ACPI_SPI_SECOND_PHASE) | |
1693 | spi->mode |= SPI_CPHA; | |
1694 | if (sb->clock_polarity == ACPI_SPI_START_HIGH) | |
1695 | spi->mode |= SPI_CPOL; | |
1696 | if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH) | |
1697 | spi->mode |= SPI_CS_HIGH; | |
1698 | } | |
1699 | } else if (spi->irq < 0) { | |
1700 | struct resource r; | |
1701 | ||
1702 | if (acpi_dev_resource_interrupt(ares, 0, &r)) | |
1703 | spi->irq = r.start; | |
1704 | } | |
1705 | ||
1706 | /* Always tell the ACPI core to skip this resource */ | |
1707 | return 1; | |
1708 | } | |
1709 | ||
7f24467f OP |
1710 | static acpi_status acpi_register_spi_device(struct spi_master *master, |
1711 | struct acpi_device *adev) | |
64bee4d2 | 1712 | { |
64bee4d2 | 1713 | struct list_head resource_list; |
64bee4d2 MW |
1714 | struct spi_device *spi; |
1715 | int ret; | |
1716 | ||
7f24467f OP |
1717 | if (acpi_bus_get_status(adev) || !adev->status.present || |
1718 | acpi_device_enumerated(adev)) | |
64bee4d2 MW |
1719 | return AE_OK; |
1720 | ||
1721 | spi = spi_alloc_device(master); | |
1722 | if (!spi) { | |
1723 | dev_err(&master->dev, "failed to allocate SPI device for %s\n", | |
1724 | dev_name(&adev->dev)); | |
1725 | return AE_NO_MEMORY; | |
1726 | } | |
1727 | ||
7b199811 | 1728 | ACPI_COMPANION_SET(&spi->dev, adev); |
64bee4d2 MW |
1729 | spi->irq = -1; |
1730 | ||
1731 | INIT_LIST_HEAD(&resource_list); | |
1732 | ret = acpi_dev_get_resources(adev, &resource_list, | |
1733 | acpi_spi_add_resource, spi); | |
1734 | acpi_dev_free_resource_list(&resource_list); | |
1735 | ||
1736 | if (ret < 0 || !spi->max_speed_hz) { | |
1737 | spi_dev_put(spi); | |
1738 | return AE_OK; | |
1739 | } | |
1740 | ||
0c6543f6 DD |
1741 | acpi_set_modalias(adev, acpi_device_hid(adev), spi->modalias, |
1742 | sizeof(spi->modalias)); | |
1743 | ||
33ada67d CR |
1744 | if (spi->irq < 0) |
1745 | spi->irq = acpi_dev_gpio_irq_get(adev, 0); | |
1746 | ||
7f24467f OP |
1747 | acpi_device_set_enumerated(adev); |
1748 | ||
33cf00e5 | 1749 | adev->power.flags.ignore_parent = true; |
64bee4d2 | 1750 | if (spi_add_device(spi)) { |
33cf00e5 | 1751 | adev->power.flags.ignore_parent = false; |
64bee4d2 MW |
1752 | dev_err(&master->dev, "failed to add SPI device %s from ACPI\n", |
1753 | dev_name(&adev->dev)); | |
1754 | spi_dev_put(spi); | |
1755 | } | |
1756 | ||
1757 | return AE_OK; | |
1758 | } | |
1759 | ||
7f24467f OP |
1760 | static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level, |
1761 | void *data, void **return_value) | |
1762 | { | |
1763 | struct spi_master *master = data; | |
1764 | struct acpi_device *adev; | |
1765 | ||
1766 | if (acpi_bus_get_device(handle, &adev)) | |
1767 | return AE_OK; | |
1768 | ||
1769 | return acpi_register_spi_device(master, adev); | |
1770 | } | |
1771 | ||
64bee4d2 MW |
1772 | static void acpi_register_spi_devices(struct spi_master *master) |
1773 | { | |
1774 | acpi_status status; | |
1775 | acpi_handle handle; | |
1776 | ||
29896178 | 1777 | handle = ACPI_HANDLE(master->dev.parent); |
64bee4d2 MW |
1778 | if (!handle) |
1779 | return; | |
1780 | ||
1781 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1, | |
1782 | acpi_spi_add_device, NULL, | |
1783 | master, NULL); | |
1784 | if (ACPI_FAILURE(status)) | |
1785 | dev_warn(&master->dev, "failed to enumerate SPI slaves\n"); | |
1786 | } | |
1787 | #else | |
1788 | static inline void acpi_register_spi_devices(struct spi_master *master) {} | |
1789 | #endif /* CONFIG_ACPI */ | |
1790 | ||
49dce689 | 1791 | static void spi_master_release(struct device *dev) |
8ae12a0d DB |
1792 | { |
1793 | struct spi_master *master; | |
1794 | ||
49dce689 | 1795 | master = container_of(dev, struct spi_master, dev); |
8ae12a0d DB |
1796 | kfree(master); |
1797 | } | |
1798 | ||
1799 | static struct class spi_master_class = { | |
1800 | .name = "spi_master", | |
1801 | .owner = THIS_MODULE, | |
49dce689 | 1802 | .dev_release = spi_master_release, |
eca2ebc7 | 1803 | .dev_groups = spi_master_groups, |
8ae12a0d DB |
1804 | }; |
1805 | ||
1806 | ||
1807 | /** | |
1808 | * spi_alloc_master - allocate SPI master controller | |
1809 | * @dev: the controller, possibly using the platform_bus | |
33e34dc6 | 1810 | * @size: how much zeroed driver-private data to allocate; the pointer to this |
49dce689 | 1811 | * memory is in the driver_data field of the returned device, |
0c868461 | 1812 | * accessible with spi_master_get_devdata(). |
33e34dc6 | 1813 | * Context: can sleep |
8ae12a0d DB |
1814 | * |
1815 | * This call is used only by SPI master controller drivers, which are the | |
1816 | * only ones directly touching chip registers. It's how they allocate | |
ba1a0513 | 1817 | * an spi_master structure, prior to calling spi_register_master(). |
8ae12a0d | 1818 | * |
97d56dc6 | 1819 | * This must be called from context that can sleep. |
8ae12a0d DB |
1820 | * |
1821 | * The caller is responsible for assigning the bus number and initializing | |
ba1a0513 | 1822 | * the master's methods before calling spi_register_master(); and (after errors |
a394d635 | 1823 | * adding the device) calling spi_master_put() to prevent a memory leak. |
97d56dc6 JMC |
1824 | * |
1825 | * Return: the SPI master structure on success, else NULL. | |
8ae12a0d | 1826 | */ |
e9d5a461 | 1827 | struct spi_master *spi_alloc_master(struct device *dev, unsigned size) |
8ae12a0d DB |
1828 | { |
1829 | struct spi_master *master; | |
1830 | ||
0c868461 DB |
1831 | if (!dev) |
1832 | return NULL; | |
1833 | ||
5fe5f05e | 1834 | master = kzalloc(size + sizeof(*master), GFP_KERNEL); |
8ae12a0d DB |
1835 | if (!master) |
1836 | return NULL; | |
1837 | ||
49dce689 | 1838 | device_initialize(&master->dev); |
1e8a52e1 GL |
1839 | master->bus_num = -1; |
1840 | master->num_chipselect = 1; | |
49dce689 | 1841 | master->dev.class = &spi_master_class; |
157f38f9 | 1842 | master->dev.parent = dev; |
d7e2ee25 | 1843 | pm_suspend_ignore_children(&master->dev, true); |
0c868461 | 1844 | spi_master_set_devdata(master, &master[1]); |
8ae12a0d DB |
1845 | |
1846 | return master; | |
1847 | } | |
1848 | EXPORT_SYMBOL_GPL(spi_alloc_master); | |
1849 | ||
74317984 JCPV |
1850 | #ifdef CONFIG_OF |
1851 | static int of_spi_register_master(struct spi_master *master) | |
1852 | { | |
e80beb27 | 1853 | int nb, i, *cs; |
74317984 JCPV |
1854 | struct device_node *np = master->dev.of_node; |
1855 | ||
1856 | if (!np) | |
1857 | return 0; | |
1858 | ||
1859 | nb = of_gpio_named_count(np, "cs-gpios"); | |
5fe5f05e | 1860 | master->num_chipselect = max_t(int, nb, master->num_chipselect); |
74317984 | 1861 | |
8ec5d84e AL |
1862 | /* Return error only for an incorrectly formed cs-gpios property */ |
1863 | if (nb == 0 || nb == -ENOENT) | |
74317984 | 1864 | return 0; |
8ec5d84e AL |
1865 | else if (nb < 0) |
1866 | return nb; | |
74317984 JCPV |
1867 | |
1868 | cs = devm_kzalloc(&master->dev, | |
1869 | sizeof(int) * master->num_chipselect, | |
1870 | GFP_KERNEL); | |
1871 | master->cs_gpios = cs; | |
1872 | ||
1873 | if (!master->cs_gpios) | |
1874 | return -ENOMEM; | |
1875 | ||
0da83bb1 | 1876 | for (i = 0; i < master->num_chipselect; i++) |
446411e1 | 1877 | cs[i] = -ENOENT; |
74317984 JCPV |
1878 | |
1879 | for (i = 0; i < nb; i++) | |
1880 | cs[i] = of_get_named_gpio(np, "cs-gpios", i); | |
1881 | ||
1882 | return 0; | |
1883 | } | |
1884 | #else | |
1885 | static int of_spi_register_master(struct spi_master *master) | |
1886 | { | |
1887 | return 0; | |
1888 | } | |
1889 | #endif | |
1890 | ||
8ae12a0d DB |
1891 | /** |
1892 | * spi_register_master - register SPI master controller | |
1893 | * @master: initialized master, originally from spi_alloc_master() | |
33e34dc6 | 1894 | * Context: can sleep |
8ae12a0d DB |
1895 | * |
1896 | * SPI master controllers connect to their drivers using some non-SPI bus, | |
1897 | * such as the platform bus. The final stage of probe() in that code | |
1898 | * includes calling spi_register_master() to hook up to this SPI bus glue. | |
1899 | * | |
1900 | * SPI controllers use board specific (often SOC specific) bus numbers, | |
1901 | * and board-specific addressing for SPI devices combines those numbers | |
1902 | * with chip select numbers. Since SPI does not directly support dynamic | |
1903 | * device identification, boards need configuration tables telling which | |
1904 | * chip is at which address. | |
1905 | * | |
1906 | * This must be called from context that can sleep. It returns zero on | |
1907 | * success, else a negative error code (dropping the master's refcount). | |
0c868461 DB |
1908 | * After a successful return, the caller is responsible for calling |
1909 | * spi_unregister_master(). | |
97d56dc6 JMC |
1910 | * |
1911 | * Return: zero on success, else a negative error code. | |
8ae12a0d | 1912 | */ |
e9d5a461 | 1913 | int spi_register_master(struct spi_master *master) |
8ae12a0d | 1914 | { |
e44a45ae | 1915 | static atomic_t dyn_bus_id = ATOMIC_INIT((1<<15) - 1); |
49dce689 | 1916 | struct device *dev = master->dev.parent; |
2b9603a0 | 1917 | struct boardinfo *bi; |
8ae12a0d DB |
1918 | int status = -ENODEV; |
1919 | int dynamic = 0; | |
1920 | ||
0c868461 DB |
1921 | if (!dev) |
1922 | return -ENODEV; | |
1923 | ||
74317984 JCPV |
1924 | status = of_spi_register_master(master); |
1925 | if (status) | |
1926 | return status; | |
1927 | ||
082c8cb4 DB |
1928 | /* even if it's just one always-selected device, there must |
1929 | * be at least one chipselect | |
1930 | */ | |
1931 | if (master->num_chipselect == 0) | |
1932 | return -EINVAL; | |
1933 | ||
bb29785e GL |
1934 | if ((master->bus_num < 0) && master->dev.of_node) |
1935 | master->bus_num = of_alias_get_id(master->dev.of_node, "spi"); | |
1936 | ||
8ae12a0d | 1937 | /* convention: dynamically assigned bus IDs count down from the max */ |
a020ed75 | 1938 | if (master->bus_num < 0) { |
082c8cb4 DB |
1939 | /* FIXME switch to an IDR based scheme, something like |
1940 | * I2C now uses, so we can't run out of "dynamic" IDs | |
1941 | */ | |
8ae12a0d | 1942 | master->bus_num = atomic_dec_return(&dyn_bus_id); |
b885244e | 1943 | dynamic = 1; |
8ae12a0d DB |
1944 | } |
1945 | ||
5424d43e MB |
1946 | INIT_LIST_HEAD(&master->queue); |
1947 | spin_lock_init(&master->queue_lock); | |
cf32b71e ES |
1948 | spin_lock_init(&master->bus_lock_spinlock); |
1949 | mutex_init(&master->bus_lock_mutex); | |
ef4d96ec | 1950 | mutex_init(&master->io_mutex); |
cf32b71e | 1951 | master->bus_lock_flag = 0; |
b158935f | 1952 | init_completion(&master->xfer_completion); |
6ad45a27 MB |
1953 | if (!master->max_dma_len) |
1954 | master->max_dma_len = INT_MAX; | |
cf32b71e | 1955 | |
8ae12a0d DB |
1956 | /* register the device, then userspace will see it. |
1957 | * registration fails if the bus ID is in use. | |
1958 | */ | |
35f74fca | 1959 | dev_set_name(&master->dev, "spi%u", master->bus_num); |
49dce689 | 1960 | status = device_add(&master->dev); |
b885244e | 1961 | if (status < 0) |
8ae12a0d | 1962 | goto done; |
35f74fca | 1963 | dev_dbg(dev, "registered master %s%s\n", dev_name(&master->dev), |
8ae12a0d DB |
1964 | dynamic ? " (dynamic)" : ""); |
1965 | ||
ffbbdd21 LW |
1966 | /* If we're using a queued driver, start the queue */ |
1967 | if (master->transfer) | |
1968 | dev_info(dev, "master is unqueued, this is deprecated\n"); | |
1969 | else { | |
1970 | status = spi_master_initialize_queue(master); | |
1971 | if (status) { | |
e93b0724 | 1972 | device_del(&master->dev); |
ffbbdd21 LW |
1973 | goto done; |
1974 | } | |
1975 | } | |
eca2ebc7 MS |
1976 | /* add statistics */ |
1977 | spin_lock_init(&master->statistics.lock); | |
ffbbdd21 | 1978 | |
2b9603a0 FT |
1979 | mutex_lock(&board_lock); |
1980 | list_add_tail(&master->list, &spi_master_list); | |
1981 | list_for_each_entry(bi, &board_list, list) | |
1982 | spi_match_master_to_boardinfo(master, &bi->board_info); | |
1983 | mutex_unlock(&board_lock); | |
1984 | ||
64bee4d2 | 1985 | /* Register devices from the device tree and ACPI */ |
12b15e83 | 1986 | of_register_spi_devices(master); |
64bee4d2 | 1987 | acpi_register_spi_devices(master); |
8ae12a0d DB |
1988 | done: |
1989 | return status; | |
1990 | } | |
1991 | EXPORT_SYMBOL_GPL(spi_register_master); | |
1992 | ||
666d5b4c MB |
1993 | static void devm_spi_unregister(struct device *dev, void *res) |
1994 | { | |
1995 | spi_unregister_master(*(struct spi_master **)res); | |
1996 | } | |
1997 | ||
1998 | /** | |
1999 | * dev_spi_register_master - register managed SPI master controller | |
2000 | * @dev: device managing SPI master | |
2001 | * @master: initialized master, originally from spi_alloc_master() | |
2002 | * Context: can sleep | |
2003 | * | |
2004 | * Register a SPI device as with spi_register_master() which will | |
2005 | * automatically be unregister | |
97d56dc6 JMC |
2006 | * |
2007 | * Return: zero on success, else a negative error code. | |
666d5b4c MB |
2008 | */ |
2009 | int devm_spi_register_master(struct device *dev, struct spi_master *master) | |
2010 | { | |
2011 | struct spi_master **ptr; | |
2012 | int ret; | |
2013 | ||
2014 | ptr = devres_alloc(devm_spi_unregister, sizeof(*ptr), GFP_KERNEL); | |
2015 | if (!ptr) | |
2016 | return -ENOMEM; | |
2017 | ||
2018 | ret = spi_register_master(master); | |
4b92894e | 2019 | if (!ret) { |
666d5b4c MB |
2020 | *ptr = master; |
2021 | devres_add(dev, ptr); | |
2022 | } else { | |
2023 | devres_free(ptr); | |
2024 | } | |
2025 | ||
2026 | return ret; | |
2027 | } | |
2028 | EXPORT_SYMBOL_GPL(devm_spi_register_master); | |
2029 | ||
34860089 | 2030 | static int __unregister(struct device *dev, void *null) |
8ae12a0d | 2031 | { |
34860089 | 2032 | spi_unregister_device(to_spi_device(dev)); |
8ae12a0d DB |
2033 | return 0; |
2034 | } | |
2035 | ||
2036 | /** | |
2037 | * spi_unregister_master - unregister SPI master controller | |
2038 | * @master: the master being unregistered | |
33e34dc6 | 2039 | * Context: can sleep |
8ae12a0d DB |
2040 | * |
2041 | * This call is used only by SPI master controller drivers, which are the | |
2042 | * only ones directly touching chip registers. | |
2043 | * | |
2044 | * This must be called from context that can sleep. | |
2045 | */ | |
2046 | void spi_unregister_master(struct spi_master *master) | |
2047 | { | |
89fc9a1a JG |
2048 | int dummy; |
2049 | ||
ffbbdd21 LW |
2050 | if (master->queued) { |
2051 | if (spi_destroy_queue(master)) | |
2052 | dev_err(&master->dev, "queue remove failed\n"); | |
2053 | } | |
2054 | ||
2b9603a0 FT |
2055 | mutex_lock(&board_lock); |
2056 | list_del(&master->list); | |
2057 | mutex_unlock(&board_lock); | |
2058 | ||
97dbf37d | 2059 | dummy = device_for_each_child(&master->dev, NULL, __unregister); |
49dce689 | 2060 | device_unregister(&master->dev); |
8ae12a0d DB |
2061 | } |
2062 | EXPORT_SYMBOL_GPL(spi_unregister_master); | |
2063 | ||
ffbbdd21 LW |
2064 | int spi_master_suspend(struct spi_master *master) |
2065 | { | |
2066 | int ret; | |
2067 | ||
2068 | /* Basically no-ops for non-queued masters */ | |
2069 | if (!master->queued) | |
2070 | return 0; | |
2071 | ||
2072 | ret = spi_stop_queue(master); | |
2073 | if (ret) | |
2074 | dev_err(&master->dev, "queue stop failed\n"); | |
2075 | ||
2076 | return ret; | |
2077 | } | |
2078 | EXPORT_SYMBOL_GPL(spi_master_suspend); | |
2079 | ||
2080 | int spi_master_resume(struct spi_master *master) | |
2081 | { | |
2082 | int ret; | |
2083 | ||
2084 | if (!master->queued) | |
2085 | return 0; | |
2086 | ||
2087 | ret = spi_start_queue(master); | |
2088 | if (ret) | |
2089 | dev_err(&master->dev, "queue restart failed\n"); | |
2090 | ||
2091 | return ret; | |
2092 | } | |
2093 | EXPORT_SYMBOL_GPL(spi_master_resume); | |
2094 | ||
9f3b795a | 2095 | static int __spi_master_match(struct device *dev, const void *data) |
5ed2c832 DY |
2096 | { |
2097 | struct spi_master *m; | |
9f3b795a | 2098 | const u16 *bus_num = data; |
5ed2c832 DY |
2099 | |
2100 | m = container_of(dev, struct spi_master, dev); | |
2101 | return m->bus_num == *bus_num; | |
2102 | } | |
2103 | ||
8ae12a0d DB |
2104 | /** |
2105 | * spi_busnum_to_master - look up master associated with bus_num | |
2106 | * @bus_num: the master's bus number | |
33e34dc6 | 2107 | * Context: can sleep |
8ae12a0d DB |
2108 | * |
2109 | * This call may be used with devices that are registered after | |
2110 | * arch init time. It returns a refcounted pointer to the relevant | |
2111 | * spi_master (which the caller must release), or NULL if there is | |
2112 | * no such master registered. | |
97d56dc6 JMC |
2113 | * |
2114 | * Return: the SPI master structure on success, else NULL. | |
8ae12a0d DB |
2115 | */ |
2116 | struct spi_master *spi_busnum_to_master(u16 bus_num) | |
2117 | { | |
49dce689 | 2118 | struct device *dev; |
1e9a51dc | 2119 | struct spi_master *master = NULL; |
5ed2c832 | 2120 | |
695794ae | 2121 | dev = class_find_device(&spi_master_class, NULL, &bus_num, |
5ed2c832 DY |
2122 | __spi_master_match); |
2123 | if (dev) | |
2124 | master = container_of(dev, struct spi_master, dev); | |
2125 | /* reference got in class_find_device */ | |
1e9a51dc | 2126 | return master; |
8ae12a0d DB |
2127 | } |
2128 | EXPORT_SYMBOL_GPL(spi_busnum_to_master); | |
2129 | ||
d780c371 MS |
2130 | /*-------------------------------------------------------------------------*/ |
2131 | ||
2132 | /* Core methods for SPI resource management */ | |
2133 | ||
2134 | /** | |
2135 | * spi_res_alloc - allocate a spi resource that is life-cycle managed | |
2136 | * during the processing of a spi_message while using | |
2137 | * spi_transfer_one | |
2138 | * @spi: the spi device for which we allocate memory | |
2139 | * @release: the release code to execute for this resource | |
2140 | * @size: size to alloc and return | |
2141 | * @gfp: GFP allocation flags | |
2142 | * | |
2143 | * Return: the pointer to the allocated data | |
2144 | * | |
2145 | * This may get enhanced in the future to allocate from a memory pool | |
2146 | * of the @spi_device or @spi_master to avoid repeated allocations. | |
2147 | */ | |
2148 | void *spi_res_alloc(struct spi_device *spi, | |
2149 | spi_res_release_t release, | |
2150 | size_t size, gfp_t gfp) | |
2151 | { | |
2152 | struct spi_res *sres; | |
2153 | ||
2154 | sres = kzalloc(sizeof(*sres) + size, gfp); | |
2155 | if (!sres) | |
2156 | return NULL; | |
2157 | ||
2158 | INIT_LIST_HEAD(&sres->entry); | |
2159 | sres->release = release; | |
2160 | ||
2161 | return sres->data; | |
2162 | } | |
2163 | EXPORT_SYMBOL_GPL(spi_res_alloc); | |
2164 | ||
2165 | /** | |
2166 | * spi_res_free - free an spi resource | |
2167 | * @res: pointer to the custom data of a resource | |
2168 | * | |
2169 | */ | |
2170 | void spi_res_free(void *res) | |
2171 | { | |
2172 | struct spi_res *sres = container_of(res, struct spi_res, data); | |
2173 | ||
2174 | if (!res) | |
2175 | return; | |
2176 | ||
2177 | WARN_ON(!list_empty(&sres->entry)); | |
2178 | kfree(sres); | |
2179 | } | |
2180 | EXPORT_SYMBOL_GPL(spi_res_free); | |
2181 | ||
2182 | /** | |
2183 | * spi_res_add - add a spi_res to the spi_message | |
2184 | * @message: the spi message | |
2185 | * @res: the spi_resource | |
2186 | */ | |
2187 | void spi_res_add(struct spi_message *message, void *res) | |
2188 | { | |
2189 | struct spi_res *sres = container_of(res, struct spi_res, data); | |
2190 | ||
2191 | WARN_ON(!list_empty(&sres->entry)); | |
2192 | list_add_tail(&sres->entry, &message->resources); | |
2193 | } | |
2194 | EXPORT_SYMBOL_GPL(spi_res_add); | |
2195 | ||
2196 | /** | |
2197 | * spi_res_release - release all spi resources for this message | |
2198 | * @master: the @spi_master | |
2199 | * @message: the @spi_message | |
2200 | */ | |
2201 | void spi_res_release(struct spi_master *master, | |
2202 | struct spi_message *message) | |
2203 | { | |
2204 | struct spi_res *res; | |
2205 | ||
2206 | while (!list_empty(&message->resources)) { | |
2207 | res = list_last_entry(&message->resources, | |
2208 | struct spi_res, entry); | |
2209 | ||
2210 | if (res->release) | |
2211 | res->release(master, message, res->data); | |
2212 | ||
2213 | list_del(&res->entry); | |
2214 | ||
2215 | kfree(res); | |
2216 | } | |
2217 | } | |
2218 | EXPORT_SYMBOL_GPL(spi_res_release); | |
8ae12a0d DB |
2219 | |
2220 | /*-------------------------------------------------------------------------*/ | |
2221 | ||
523baf5a MS |
2222 | /* Core methods for spi_message alterations */ |
2223 | ||
2224 | static void __spi_replace_transfers_release(struct spi_master *master, | |
2225 | struct spi_message *msg, | |
2226 | void *res) | |
2227 | { | |
2228 | struct spi_replaced_transfers *rxfer = res; | |
2229 | size_t i; | |
2230 | ||
2231 | /* call extra callback if requested */ | |
2232 | if (rxfer->release) | |
2233 | rxfer->release(master, msg, res); | |
2234 | ||
2235 | /* insert replaced transfers back into the message */ | |
2236 | list_splice(&rxfer->replaced_transfers, rxfer->replaced_after); | |
2237 | ||
2238 | /* remove the formerly inserted entries */ | |
2239 | for (i = 0; i < rxfer->inserted; i++) | |
2240 | list_del(&rxfer->inserted_transfers[i].transfer_list); | |
2241 | } | |
2242 | ||
2243 | /** | |
2244 | * spi_replace_transfers - replace transfers with several transfers | |
2245 | * and register change with spi_message.resources | |
2246 | * @msg: the spi_message we work upon | |
2247 | * @xfer_first: the first spi_transfer we want to replace | |
2248 | * @remove: number of transfers to remove | |
2249 | * @insert: the number of transfers we want to insert instead | |
2250 | * @release: extra release code necessary in some circumstances | |
2251 | * @extradatasize: extra data to allocate (with alignment guarantees | |
2252 | * of struct @spi_transfer) | |
05885397 | 2253 | * @gfp: gfp flags |
523baf5a MS |
2254 | * |
2255 | * Returns: pointer to @spi_replaced_transfers, | |
2256 | * PTR_ERR(...) in case of errors. | |
2257 | */ | |
2258 | struct spi_replaced_transfers *spi_replace_transfers( | |
2259 | struct spi_message *msg, | |
2260 | struct spi_transfer *xfer_first, | |
2261 | size_t remove, | |
2262 | size_t insert, | |
2263 | spi_replaced_release_t release, | |
2264 | size_t extradatasize, | |
2265 | gfp_t gfp) | |
2266 | { | |
2267 | struct spi_replaced_transfers *rxfer; | |
2268 | struct spi_transfer *xfer; | |
2269 | size_t i; | |
2270 | ||
2271 | /* allocate the structure using spi_res */ | |
2272 | rxfer = spi_res_alloc(msg->spi, __spi_replace_transfers_release, | |
2273 | insert * sizeof(struct spi_transfer) | |
2274 | + sizeof(struct spi_replaced_transfers) | |
2275 | + extradatasize, | |
2276 | gfp); | |
2277 | if (!rxfer) | |
2278 | return ERR_PTR(-ENOMEM); | |
2279 | ||
2280 | /* the release code to invoke before running the generic release */ | |
2281 | rxfer->release = release; | |
2282 | ||
2283 | /* assign extradata */ | |
2284 | if (extradatasize) | |
2285 | rxfer->extradata = | |
2286 | &rxfer->inserted_transfers[insert]; | |
2287 | ||
2288 | /* init the replaced_transfers list */ | |
2289 | INIT_LIST_HEAD(&rxfer->replaced_transfers); | |
2290 | ||
2291 | /* assign the list_entry after which we should reinsert | |
2292 | * the @replaced_transfers - it may be spi_message.messages! | |
2293 | */ | |
2294 | rxfer->replaced_after = xfer_first->transfer_list.prev; | |
2295 | ||
2296 | /* remove the requested number of transfers */ | |
2297 | for (i = 0; i < remove; i++) { | |
2298 | /* if the entry after replaced_after it is msg->transfers | |
2299 | * then we have been requested to remove more transfers | |
2300 | * than are in the list | |
2301 | */ | |
2302 | if (rxfer->replaced_after->next == &msg->transfers) { | |
2303 | dev_err(&msg->spi->dev, | |
2304 | "requested to remove more spi_transfers than are available\n"); | |
2305 | /* insert replaced transfers back into the message */ | |
2306 | list_splice(&rxfer->replaced_transfers, | |
2307 | rxfer->replaced_after); | |
2308 | ||
2309 | /* free the spi_replace_transfer structure */ | |
2310 | spi_res_free(rxfer); | |
2311 | ||
2312 | /* and return with an error */ | |
2313 | return ERR_PTR(-EINVAL); | |
2314 | } | |
2315 | ||
2316 | /* remove the entry after replaced_after from list of | |
2317 | * transfers and add it to list of replaced_transfers | |
2318 | */ | |
2319 | list_move_tail(rxfer->replaced_after->next, | |
2320 | &rxfer->replaced_transfers); | |
2321 | } | |
2322 | ||
2323 | /* create copy of the given xfer with identical settings | |
2324 | * based on the first transfer to get removed | |
2325 | */ | |
2326 | for (i = 0; i < insert; i++) { | |
2327 | /* we need to run in reverse order */ | |
2328 | xfer = &rxfer->inserted_transfers[insert - 1 - i]; | |
2329 | ||
2330 | /* copy all spi_transfer data */ | |
2331 | memcpy(xfer, xfer_first, sizeof(*xfer)); | |
2332 | ||
2333 | /* add to list */ | |
2334 | list_add(&xfer->transfer_list, rxfer->replaced_after); | |
2335 | ||
2336 | /* clear cs_change and delay_usecs for all but the last */ | |
2337 | if (i) { | |
2338 | xfer->cs_change = false; | |
2339 | xfer->delay_usecs = 0; | |
2340 | } | |
2341 | } | |
2342 | ||
2343 | /* set up inserted */ | |
2344 | rxfer->inserted = insert; | |
2345 | ||
2346 | /* and register it with spi_res/spi_message */ | |
2347 | spi_res_add(msg, rxfer); | |
2348 | ||
2349 | return rxfer; | |
2350 | } | |
2351 | EXPORT_SYMBOL_GPL(spi_replace_transfers); | |
2352 | ||
08933418 FE |
2353 | static int __spi_split_transfer_maxsize(struct spi_master *master, |
2354 | struct spi_message *msg, | |
2355 | struct spi_transfer **xferp, | |
2356 | size_t maxsize, | |
2357 | gfp_t gfp) | |
d9f12122 MS |
2358 | { |
2359 | struct spi_transfer *xfer = *xferp, *xfers; | |
2360 | struct spi_replaced_transfers *srt; | |
2361 | size_t offset; | |
2362 | size_t count, i; | |
2363 | ||
2364 | /* warn once about this fact that we are splitting a transfer */ | |
2365 | dev_warn_once(&msg->spi->dev, | |
7d62f51e | 2366 | "spi_transfer of length %i exceed max length of %zu - needed to split transfers\n", |
d9f12122 MS |
2367 | xfer->len, maxsize); |
2368 | ||
2369 | /* calculate how many we have to replace */ | |
2370 | count = DIV_ROUND_UP(xfer->len, maxsize); | |
2371 | ||
2372 | /* create replacement */ | |
2373 | srt = spi_replace_transfers(msg, xfer, 1, count, NULL, 0, gfp); | |
657d32ef DC |
2374 | if (IS_ERR(srt)) |
2375 | return PTR_ERR(srt); | |
d9f12122 MS |
2376 | xfers = srt->inserted_transfers; |
2377 | ||
2378 | /* now handle each of those newly inserted spi_transfers | |
2379 | * note that the replacements spi_transfers all are preset | |
2380 | * to the same values as *xferp, so tx_buf, rx_buf and len | |
2381 | * are all identical (as well as most others) | |
2382 | * so we just have to fix up len and the pointers. | |
2383 | * | |
2384 | * this also includes support for the depreciated | |
2385 | * spi_message.is_dma_mapped interface | |
2386 | */ | |
2387 | ||
2388 | /* the first transfer just needs the length modified, so we | |
2389 | * run it outside the loop | |
2390 | */ | |
c8dab77a | 2391 | xfers[0].len = min_t(size_t, maxsize, xfer[0].len); |
d9f12122 MS |
2392 | |
2393 | /* all the others need rx_buf/tx_buf also set */ | |
2394 | for (i = 1, offset = maxsize; i < count; offset += maxsize, i++) { | |
2395 | /* update rx_buf, tx_buf and dma */ | |
2396 | if (xfers[i].rx_buf) | |
2397 | xfers[i].rx_buf += offset; | |
2398 | if (xfers[i].rx_dma) | |
2399 | xfers[i].rx_dma += offset; | |
2400 | if (xfers[i].tx_buf) | |
2401 | xfers[i].tx_buf += offset; | |
2402 | if (xfers[i].tx_dma) | |
2403 | xfers[i].tx_dma += offset; | |
2404 | ||
2405 | /* update length */ | |
2406 | xfers[i].len = min(maxsize, xfers[i].len - offset); | |
2407 | } | |
2408 | ||
2409 | /* we set up xferp to the last entry we have inserted, | |
2410 | * so that we skip those already split transfers | |
2411 | */ | |
2412 | *xferp = &xfers[count - 1]; | |
2413 | ||
2414 | /* increment statistics counters */ | |
2415 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, | |
2416 | transfers_split_maxsize); | |
2417 | SPI_STATISTICS_INCREMENT_FIELD(&msg->spi->statistics, | |
2418 | transfers_split_maxsize); | |
2419 | ||
2420 | return 0; | |
2421 | } | |
2422 | ||
2423 | /** | |
2424 | * spi_split_tranfers_maxsize - split spi transfers into multiple transfers | |
2425 | * when an individual transfer exceeds a | |
2426 | * certain size | |
2427 | * @master: the @spi_master for this transfer | |
3700ce95 MI |
2428 | * @msg: the @spi_message to transform |
2429 | * @maxsize: the maximum when to apply this | |
10f11a22 | 2430 | * @gfp: GFP allocation flags |
d9f12122 MS |
2431 | * |
2432 | * Return: status of transformation | |
2433 | */ | |
2434 | int spi_split_transfers_maxsize(struct spi_master *master, | |
2435 | struct spi_message *msg, | |
2436 | size_t maxsize, | |
2437 | gfp_t gfp) | |
2438 | { | |
2439 | struct spi_transfer *xfer; | |
2440 | int ret; | |
2441 | ||
2442 | /* iterate over the transfer_list, | |
2443 | * but note that xfer is advanced to the last transfer inserted | |
2444 | * to avoid checking sizes again unnecessarily (also xfer does | |
2445 | * potentiall belong to a different list by the time the | |
2446 | * replacement has happened | |
2447 | */ | |
2448 | list_for_each_entry(xfer, &msg->transfers, transfer_list) { | |
2449 | if (xfer->len > maxsize) { | |
2450 | ret = __spi_split_transfer_maxsize( | |
2451 | master, msg, &xfer, maxsize, gfp); | |
2452 | if (ret) | |
2453 | return ret; | |
2454 | } | |
2455 | } | |
2456 | ||
2457 | return 0; | |
2458 | } | |
2459 | EXPORT_SYMBOL_GPL(spi_split_transfers_maxsize); | |
8ae12a0d DB |
2460 | |
2461 | /*-------------------------------------------------------------------------*/ | |
2462 | ||
7d077197 DB |
2463 | /* Core methods for SPI master protocol drivers. Some of the |
2464 | * other core methods are currently defined as inline functions. | |
2465 | */ | |
2466 | ||
63ab645f SB |
2467 | static int __spi_validate_bits_per_word(struct spi_master *master, u8 bits_per_word) |
2468 | { | |
2469 | if (master->bits_per_word_mask) { | |
2470 | /* Only 32 bits fit in the mask */ | |
2471 | if (bits_per_word > 32) | |
2472 | return -EINVAL; | |
2473 | if (!(master->bits_per_word_mask & | |
2474 | SPI_BPW_MASK(bits_per_word))) | |
2475 | return -EINVAL; | |
2476 | } | |
2477 | ||
2478 | return 0; | |
2479 | } | |
2480 | ||
7d077197 DB |
2481 | /** |
2482 | * spi_setup - setup SPI mode and clock rate | |
2483 | * @spi: the device whose settings are being modified | |
2484 | * Context: can sleep, and no requests are queued to the device | |
2485 | * | |
2486 | * SPI protocol drivers may need to update the transfer mode if the | |
2487 | * device doesn't work with its default. They may likewise need | |
2488 | * to update clock rates or word sizes from initial values. This function | |
2489 | * changes those settings, and must be called from a context that can sleep. | |
2490 | * Except for SPI_CS_HIGH, which takes effect immediately, the changes take | |
2491 | * effect the next time the device is selected and data is transferred to | |
2492 | * or from it. When this function returns, the spi device is deselected. | |
2493 | * | |
2494 | * Note that this call will fail if the protocol driver specifies an option | |
2495 | * that the underlying controller or its driver does not support. For | |
2496 | * example, not all hardware supports wire transfers using nine bit words, | |
2497 | * LSB-first wire encoding, or active-high chipselects. | |
97d56dc6 JMC |
2498 | * |
2499 | * Return: zero on success, else a negative error code. | |
7d077197 DB |
2500 | */ |
2501 | int spi_setup(struct spi_device *spi) | |
2502 | { | |
83596fbe | 2503 | unsigned bad_bits, ugly_bits; |
5ab8d262 | 2504 | int status; |
7d077197 | 2505 | |
f477b7fb | 2506 | /* check mode to prevent that DUAL and QUAD set at the same time |
2507 | */ | |
2508 | if (((spi->mode & SPI_TX_DUAL) && (spi->mode & SPI_TX_QUAD)) || | |
2509 | ((spi->mode & SPI_RX_DUAL) && (spi->mode & SPI_RX_QUAD))) { | |
2510 | dev_err(&spi->dev, | |
2511 | "setup: can not select dual and quad at the same time\n"); | |
2512 | return -EINVAL; | |
2513 | } | |
2514 | /* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden | |
2515 | */ | |
2516 | if ((spi->mode & SPI_3WIRE) && (spi->mode & | |
2517 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD))) | |
2518 | return -EINVAL; | |
e7db06b5 DB |
2519 | /* help drivers fail *cleanly* when they need options |
2520 | * that aren't supported with their current master | |
2521 | */ | |
2522 | bad_bits = spi->mode & ~spi->master->mode_bits; | |
83596fbe GU |
2523 | ugly_bits = bad_bits & |
2524 | (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD); | |
2525 | if (ugly_bits) { | |
2526 | dev_warn(&spi->dev, | |
2527 | "setup: ignoring unsupported mode bits %x\n", | |
2528 | ugly_bits); | |
2529 | spi->mode &= ~ugly_bits; | |
2530 | bad_bits &= ~ugly_bits; | |
2531 | } | |
e7db06b5 | 2532 | if (bad_bits) { |
eb288a1f | 2533 | dev_err(&spi->dev, "setup: unsupported mode bits %x\n", |
e7db06b5 DB |
2534 | bad_bits); |
2535 | return -EINVAL; | |
2536 | } | |
2537 | ||
7d077197 DB |
2538 | if (!spi->bits_per_word) |
2539 | spi->bits_per_word = 8; | |
2540 | ||
5ab8d262 AS |
2541 | status = __spi_validate_bits_per_word(spi->master, spi->bits_per_word); |
2542 | if (status) | |
2543 | return status; | |
63ab645f | 2544 | |
052eb2d4 AL |
2545 | if (!spi->max_speed_hz) |
2546 | spi->max_speed_hz = spi->master->max_speed_hz; | |
2547 | ||
caae070c LD |
2548 | if (spi->master->setup) |
2549 | status = spi->master->setup(spi); | |
7d077197 | 2550 | |
abeedb01 FCJ |
2551 | spi_set_cs(spi, false); |
2552 | ||
5fe5f05e | 2553 | dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n", |
7d077197 DB |
2554 | (int) (spi->mode & (SPI_CPOL | SPI_CPHA)), |
2555 | (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "", | |
2556 | (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "", | |
2557 | (spi->mode & SPI_3WIRE) ? "3wire, " : "", | |
2558 | (spi->mode & SPI_LOOP) ? "loopback, " : "", | |
2559 | spi->bits_per_word, spi->max_speed_hz, | |
2560 | status); | |
2561 | ||
2562 | return status; | |
2563 | } | |
2564 | EXPORT_SYMBOL_GPL(spi_setup); | |
2565 | ||
90808738 | 2566 | static int __spi_validate(struct spi_device *spi, struct spi_message *message) |
cf32b71e ES |
2567 | { |
2568 | struct spi_master *master = spi->master; | |
e6811d1d | 2569 | struct spi_transfer *xfer; |
6ea31293 | 2570 | int w_size; |
cf32b71e | 2571 | |
24a0013a MB |
2572 | if (list_empty(&message->transfers)) |
2573 | return -EINVAL; | |
24a0013a | 2574 | |
cf32b71e ES |
2575 | /* Half-duplex links include original MicroWire, and ones with |
2576 | * only one data pin like SPI_3WIRE (switches direction) or where | |
2577 | * either MOSI or MISO is missing. They can also be caused by | |
2578 | * software limitations. | |
2579 | */ | |
2580 | if ((master->flags & SPI_MASTER_HALF_DUPLEX) | |
2581 | || (spi->mode & SPI_3WIRE)) { | |
cf32b71e ES |
2582 | unsigned flags = master->flags; |
2583 | ||
2584 | list_for_each_entry(xfer, &message->transfers, transfer_list) { | |
2585 | if (xfer->rx_buf && xfer->tx_buf) | |
2586 | return -EINVAL; | |
2587 | if ((flags & SPI_MASTER_NO_TX) && xfer->tx_buf) | |
2588 | return -EINVAL; | |
2589 | if ((flags & SPI_MASTER_NO_RX) && xfer->rx_buf) | |
2590 | return -EINVAL; | |
2591 | } | |
2592 | } | |
2593 | ||
e6811d1d | 2594 | /** |
059b8ffe LD |
2595 | * Set transfer bits_per_word and max speed as spi device default if |
2596 | * it is not set for this transfer. | |
f477b7fb | 2597 | * Set transfer tx_nbits and rx_nbits as single transfer default |
2598 | * (SPI_NBITS_SINGLE) if it is not set for this transfer. | |
e6811d1d | 2599 | */ |
77e80588 | 2600 | message->frame_length = 0; |
e6811d1d | 2601 | list_for_each_entry(xfer, &message->transfers, transfer_list) { |
078726ce | 2602 | message->frame_length += xfer->len; |
e6811d1d LD |
2603 | if (!xfer->bits_per_word) |
2604 | xfer->bits_per_word = spi->bits_per_word; | |
a6f87fad AL |
2605 | |
2606 | if (!xfer->speed_hz) | |
059b8ffe | 2607 | xfer->speed_hz = spi->max_speed_hz; |
7dc9fbc3 MB |
2608 | if (!xfer->speed_hz) |
2609 | xfer->speed_hz = master->max_speed_hz; | |
a6f87fad AL |
2610 | |
2611 | if (master->max_speed_hz && | |
2612 | xfer->speed_hz > master->max_speed_hz) | |
2613 | xfer->speed_hz = master->max_speed_hz; | |
56ede94a | 2614 | |
63ab645f SB |
2615 | if (__spi_validate_bits_per_word(master, xfer->bits_per_word)) |
2616 | return -EINVAL; | |
a2fd4f9f | 2617 | |
4d94bd21 II |
2618 | /* |
2619 | * SPI transfer length should be multiple of SPI word size | |
2620 | * where SPI word size should be power-of-two multiple | |
2621 | */ | |
2622 | if (xfer->bits_per_word <= 8) | |
2623 | w_size = 1; | |
2624 | else if (xfer->bits_per_word <= 16) | |
2625 | w_size = 2; | |
2626 | else | |
2627 | w_size = 4; | |
2628 | ||
4d94bd21 | 2629 | /* No partial transfers accepted */ |
6ea31293 | 2630 | if (xfer->len % w_size) |
4d94bd21 II |
2631 | return -EINVAL; |
2632 | ||
a2fd4f9f MB |
2633 | if (xfer->speed_hz && master->min_speed_hz && |
2634 | xfer->speed_hz < master->min_speed_hz) | |
2635 | return -EINVAL; | |
f477b7fb | 2636 | |
2637 | if (xfer->tx_buf && !xfer->tx_nbits) | |
2638 | xfer->tx_nbits = SPI_NBITS_SINGLE; | |
2639 | if (xfer->rx_buf && !xfer->rx_nbits) | |
2640 | xfer->rx_nbits = SPI_NBITS_SINGLE; | |
2641 | /* check transfer tx/rx_nbits: | |
1afd9989 GU |
2642 | * 1. check the value matches one of single, dual and quad |
2643 | * 2. check tx/rx_nbits match the mode in spi_device | |
f477b7fb | 2644 | */ |
db90a441 SP |
2645 | if (xfer->tx_buf) { |
2646 | if (xfer->tx_nbits != SPI_NBITS_SINGLE && | |
2647 | xfer->tx_nbits != SPI_NBITS_DUAL && | |
2648 | xfer->tx_nbits != SPI_NBITS_QUAD) | |
2649 | return -EINVAL; | |
2650 | if ((xfer->tx_nbits == SPI_NBITS_DUAL) && | |
2651 | !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) | |
2652 | return -EINVAL; | |
2653 | if ((xfer->tx_nbits == SPI_NBITS_QUAD) && | |
2654 | !(spi->mode & SPI_TX_QUAD)) | |
2655 | return -EINVAL; | |
db90a441 | 2656 | } |
f477b7fb | 2657 | /* check transfer rx_nbits */ |
db90a441 SP |
2658 | if (xfer->rx_buf) { |
2659 | if (xfer->rx_nbits != SPI_NBITS_SINGLE && | |
2660 | xfer->rx_nbits != SPI_NBITS_DUAL && | |
2661 | xfer->rx_nbits != SPI_NBITS_QUAD) | |
2662 | return -EINVAL; | |
2663 | if ((xfer->rx_nbits == SPI_NBITS_DUAL) && | |
2664 | !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) | |
2665 | return -EINVAL; | |
2666 | if ((xfer->rx_nbits == SPI_NBITS_QUAD) && | |
2667 | !(spi->mode & SPI_RX_QUAD)) | |
2668 | return -EINVAL; | |
db90a441 | 2669 | } |
e6811d1d LD |
2670 | } |
2671 | ||
cf32b71e | 2672 | message->status = -EINPROGRESS; |
90808738 MB |
2673 | |
2674 | return 0; | |
2675 | } | |
2676 | ||
2677 | static int __spi_async(struct spi_device *spi, struct spi_message *message) | |
2678 | { | |
2679 | struct spi_master *master = spi->master; | |
2680 | ||
2681 | message->spi = spi; | |
2682 | ||
eca2ebc7 MS |
2683 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_async); |
2684 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_async); | |
2685 | ||
90808738 MB |
2686 | trace_spi_message_submit(message); |
2687 | ||
cf32b71e ES |
2688 | return master->transfer(spi, message); |
2689 | } | |
2690 | ||
568d0697 DB |
2691 | /** |
2692 | * spi_async - asynchronous SPI transfer | |
2693 | * @spi: device with which data will be exchanged | |
2694 | * @message: describes the data transfers, including completion callback | |
2695 | * Context: any (irqs may be blocked, etc) | |
2696 | * | |
2697 | * This call may be used in_irq and other contexts which can't sleep, | |
2698 | * as well as from task contexts which can sleep. | |
2699 | * | |
2700 | * The completion callback is invoked in a context which can't sleep. | |
2701 | * Before that invocation, the value of message->status is undefined. | |
2702 | * When the callback is issued, message->status holds either zero (to | |
2703 | * indicate complete success) or a negative error code. After that | |
2704 | * callback returns, the driver which issued the transfer request may | |
2705 | * deallocate the associated memory; it's no longer in use by any SPI | |
2706 | * core or controller driver code. | |
2707 | * | |
2708 | * Note that although all messages to a spi_device are handled in | |
2709 | * FIFO order, messages may go to different devices in other orders. | |
2710 | * Some device might be higher priority, or have various "hard" access | |
2711 | * time requirements, for example. | |
2712 | * | |
2713 | * On detection of any fault during the transfer, processing of | |
2714 | * the entire message is aborted, and the device is deselected. | |
2715 | * Until returning from the associated message completion callback, | |
2716 | * no other spi_message queued to that device will be processed. | |
2717 | * (This rule applies equally to all the synchronous transfer calls, | |
2718 | * which are wrappers around this core asynchronous primitive.) | |
97d56dc6 JMC |
2719 | * |
2720 | * Return: zero on success, else a negative error code. | |
568d0697 DB |
2721 | */ |
2722 | int spi_async(struct spi_device *spi, struct spi_message *message) | |
2723 | { | |
2724 | struct spi_master *master = spi->master; | |
cf32b71e ES |
2725 | int ret; |
2726 | unsigned long flags; | |
568d0697 | 2727 | |
90808738 MB |
2728 | ret = __spi_validate(spi, message); |
2729 | if (ret != 0) | |
2730 | return ret; | |
2731 | ||
cf32b71e | 2732 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
568d0697 | 2733 | |
cf32b71e ES |
2734 | if (master->bus_lock_flag) |
2735 | ret = -EBUSY; | |
2736 | else | |
2737 | ret = __spi_async(spi, message); | |
568d0697 | 2738 | |
cf32b71e ES |
2739 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); |
2740 | ||
2741 | return ret; | |
568d0697 DB |
2742 | } |
2743 | EXPORT_SYMBOL_GPL(spi_async); | |
2744 | ||
cf32b71e ES |
2745 | /** |
2746 | * spi_async_locked - version of spi_async with exclusive bus usage | |
2747 | * @spi: device with which data will be exchanged | |
2748 | * @message: describes the data transfers, including completion callback | |
2749 | * Context: any (irqs may be blocked, etc) | |
2750 | * | |
2751 | * This call may be used in_irq and other contexts which can't sleep, | |
2752 | * as well as from task contexts which can sleep. | |
2753 | * | |
2754 | * The completion callback is invoked in a context which can't sleep. | |
2755 | * Before that invocation, the value of message->status is undefined. | |
2756 | * When the callback is issued, message->status holds either zero (to | |
2757 | * indicate complete success) or a negative error code. After that | |
2758 | * callback returns, the driver which issued the transfer request may | |
2759 | * deallocate the associated memory; it's no longer in use by any SPI | |
2760 | * core or controller driver code. | |
2761 | * | |
2762 | * Note that although all messages to a spi_device are handled in | |
2763 | * FIFO order, messages may go to different devices in other orders. | |
2764 | * Some device might be higher priority, or have various "hard" access | |
2765 | * time requirements, for example. | |
2766 | * | |
2767 | * On detection of any fault during the transfer, processing of | |
2768 | * the entire message is aborted, and the device is deselected. | |
2769 | * Until returning from the associated message completion callback, | |
2770 | * no other spi_message queued to that device will be processed. | |
2771 | * (This rule applies equally to all the synchronous transfer calls, | |
2772 | * which are wrappers around this core asynchronous primitive.) | |
97d56dc6 JMC |
2773 | * |
2774 | * Return: zero on success, else a negative error code. | |
cf32b71e ES |
2775 | */ |
2776 | int spi_async_locked(struct spi_device *spi, struct spi_message *message) | |
2777 | { | |
2778 | struct spi_master *master = spi->master; | |
2779 | int ret; | |
2780 | unsigned long flags; | |
2781 | ||
90808738 MB |
2782 | ret = __spi_validate(spi, message); |
2783 | if (ret != 0) | |
2784 | return ret; | |
2785 | ||
cf32b71e ES |
2786 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); |
2787 | ||
2788 | ret = __spi_async(spi, message); | |
2789 | ||
2790 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); | |
2791 | ||
2792 | return ret; | |
2793 | ||
2794 | } | |
2795 | EXPORT_SYMBOL_GPL(spi_async_locked); | |
2796 | ||
7d077197 | 2797 | |
556351f1 V |
2798 | int spi_flash_read(struct spi_device *spi, |
2799 | struct spi_flash_read_message *msg) | |
2800 | ||
2801 | { | |
2802 | struct spi_master *master = spi->master; | |
f4502dd1 | 2803 | struct device *rx_dev = NULL; |
556351f1 V |
2804 | int ret; |
2805 | ||
2806 | if ((msg->opcode_nbits == SPI_NBITS_DUAL || | |
2807 | msg->addr_nbits == SPI_NBITS_DUAL) && | |
2808 | !(spi->mode & (SPI_TX_DUAL | SPI_TX_QUAD))) | |
2809 | return -EINVAL; | |
2810 | if ((msg->opcode_nbits == SPI_NBITS_QUAD || | |
2811 | msg->addr_nbits == SPI_NBITS_QUAD) && | |
2812 | !(spi->mode & SPI_TX_QUAD)) | |
2813 | return -EINVAL; | |
2814 | if (msg->data_nbits == SPI_NBITS_DUAL && | |
2815 | !(spi->mode & (SPI_RX_DUAL | SPI_RX_QUAD))) | |
2816 | return -EINVAL; | |
2817 | if (msg->data_nbits == SPI_NBITS_QUAD && | |
2818 | !(spi->mode & SPI_RX_QUAD)) | |
2819 | return -EINVAL; | |
2820 | ||
2821 | if (master->auto_runtime_pm) { | |
2822 | ret = pm_runtime_get_sync(master->dev.parent); | |
2823 | if (ret < 0) { | |
2824 | dev_err(&master->dev, "Failed to power device: %d\n", | |
2825 | ret); | |
2826 | return ret; | |
2827 | } | |
2828 | } | |
f4502dd1 | 2829 | |
556351f1 | 2830 | mutex_lock(&master->bus_lock_mutex); |
ef4d96ec | 2831 | mutex_lock(&master->io_mutex); |
f4502dd1 V |
2832 | if (master->dma_rx) { |
2833 | rx_dev = master->dma_rx->device->dev; | |
2834 | ret = spi_map_buf(master, rx_dev, &msg->rx_sg, | |
2835 | msg->buf, msg->len, | |
2836 | DMA_FROM_DEVICE); | |
2837 | if (!ret) | |
2838 | msg->cur_msg_mapped = true; | |
2839 | } | |
556351f1 | 2840 | ret = master->spi_flash_read(spi, msg); |
f4502dd1 V |
2841 | if (msg->cur_msg_mapped) |
2842 | spi_unmap_buf(master, rx_dev, &msg->rx_sg, | |
2843 | DMA_FROM_DEVICE); | |
ef4d96ec | 2844 | mutex_unlock(&master->io_mutex); |
556351f1 | 2845 | mutex_unlock(&master->bus_lock_mutex); |
f4502dd1 | 2846 | |
556351f1 V |
2847 | if (master->auto_runtime_pm) |
2848 | pm_runtime_put(master->dev.parent); | |
2849 | ||
2850 | return ret; | |
2851 | } | |
2852 | EXPORT_SYMBOL_GPL(spi_flash_read); | |
2853 | ||
7d077197 DB |
2854 | /*-------------------------------------------------------------------------*/ |
2855 | ||
2856 | /* Utility methods for SPI master protocol drivers, layered on | |
2857 | * top of the core. Some other utility methods are defined as | |
2858 | * inline functions. | |
2859 | */ | |
2860 | ||
5d870c8e AM |
2861 | static void spi_complete(void *arg) |
2862 | { | |
2863 | complete(arg); | |
2864 | } | |
2865 | ||
ef4d96ec | 2866 | static int __spi_sync(struct spi_device *spi, struct spi_message *message) |
cf32b71e ES |
2867 | { |
2868 | DECLARE_COMPLETION_ONSTACK(done); | |
2869 | int status; | |
2870 | struct spi_master *master = spi->master; | |
0461a414 MB |
2871 | unsigned long flags; |
2872 | ||
2873 | status = __spi_validate(spi, message); | |
2874 | if (status != 0) | |
2875 | return status; | |
cf32b71e ES |
2876 | |
2877 | message->complete = spi_complete; | |
2878 | message->context = &done; | |
0461a414 | 2879 | message->spi = spi; |
cf32b71e | 2880 | |
eca2ebc7 MS |
2881 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, spi_sync); |
2882 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_sync); | |
2883 | ||
0461a414 MB |
2884 | /* If we're not using the legacy transfer method then we will |
2885 | * try to transfer in the calling context so special case. | |
2886 | * This code would be less tricky if we could remove the | |
2887 | * support for driver implemented message queues. | |
2888 | */ | |
2889 | if (master->transfer == spi_queued_transfer) { | |
2890 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); | |
2891 | ||
2892 | trace_spi_message_submit(message); | |
2893 | ||
2894 | status = __spi_queued_transfer(spi, message, false); | |
2895 | ||
2896 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); | |
2897 | } else { | |
2898 | status = spi_async_locked(spi, message); | |
2899 | } | |
cf32b71e | 2900 | |
cf32b71e | 2901 | if (status == 0) { |
0461a414 MB |
2902 | /* Push out the messages in the calling context if we |
2903 | * can. | |
2904 | */ | |
eca2ebc7 MS |
2905 | if (master->transfer == spi_queued_transfer) { |
2906 | SPI_STATISTICS_INCREMENT_FIELD(&master->statistics, | |
2907 | spi_sync_immediate); | |
2908 | SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, | |
2909 | spi_sync_immediate); | |
ef4d96ec | 2910 | __spi_pump_messages(master, false); |
eca2ebc7 | 2911 | } |
0461a414 | 2912 | |
cf32b71e ES |
2913 | wait_for_completion(&done); |
2914 | status = message->status; | |
2915 | } | |
2916 | message->context = NULL; | |
2917 | return status; | |
2918 | } | |
2919 | ||
8ae12a0d DB |
2920 | /** |
2921 | * spi_sync - blocking/synchronous SPI data transfers | |
2922 | * @spi: device with which data will be exchanged | |
2923 | * @message: describes the data transfers | |
33e34dc6 | 2924 | * Context: can sleep |
8ae12a0d DB |
2925 | * |
2926 | * This call may only be used from a context that may sleep. The sleep | |
2927 | * is non-interruptible, and has no timeout. Low-overhead controller | |
2928 | * drivers may DMA directly into and out of the message buffers. | |
2929 | * | |
2930 | * Note that the SPI device's chip select is active during the message, | |
2931 | * and then is normally disabled between messages. Drivers for some | |
2932 | * frequently-used devices may want to minimize costs of selecting a chip, | |
2933 | * by leaving it selected in anticipation that the next message will go | |
2934 | * to the same chip. (That may increase power usage.) | |
2935 | * | |
0c868461 DB |
2936 | * Also, the caller is guaranteeing that the memory associated with the |
2937 | * message will not be freed before this call returns. | |
2938 | * | |
97d56dc6 | 2939 | * Return: zero on success, else a negative error code. |
8ae12a0d DB |
2940 | */ |
2941 | int spi_sync(struct spi_device *spi, struct spi_message *message) | |
2942 | { | |
ef4d96ec MB |
2943 | int ret; |
2944 | ||
2945 | mutex_lock(&spi->master->bus_lock_mutex); | |
2946 | ret = __spi_sync(spi, message); | |
2947 | mutex_unlock(&spi->master->bus_lock_mutex); | |
2948 | ||
2949 | return ret; | |
8ae12a0d DB |
2950 | } |
2951 | EXPORT_SYMBOL_GPL(spi_sync); | |
2952 | ||
cf32b71e ES |
2953 | /** |
2954 | * spi_sync_locked - version of spi_sync with exclusive bus usage | |
2955 | * @spi: device with which data will be exchanged | |
2956 | * @message: describes the data transfers | |
2957 | * Context: can sleep | |
2958 | * | |
2959 | * This call may only be used from a context that may sleep. The sleep | |
2960 | * is non-interruptible, and has no timeout. Low-overhead controller | |
2961 | * drivers may DMA directly into and out of the message buffers. | |
2962 | * | |
2963 | * This call should be used by drivers that require exclusive access to the | |
25985edc | 2964 | * SPI bus. It has to be preceded by a spi_bus_lock call. The SPI bus must |
cf32b71e ES |
2965 | * be released by a spi_bus_unlock call when the exclusive access is over. |
2966 | * | |
97d56dc6 | 2967 | * Return: zero on success, else a negative error code. |
cf32b71e ES |
2968 | */ |
2969 | int spi_sync_locked(struct spi_device *spi, struct spi_message *message) | |
2970 | { | |
ef4d96ec | 2971 | return __spi_sync(spi, message); |
cf32b71e ES |
2972 | } |
2973 | EXPORT_SYMBOL_GPL(spi_sync_locked); | |
2974 | ||
2975 | /** | |
2976 | * spi_bus_lock - obtain a lock for exclusive SPI bus usage | |
2977 | * @master: SPI bus master that should be locked for exclusive bus access | |
2978 | * Context: can sleep | |
2979 | * | |
2980 | * This call may only be used from a context that may sleep. The sleep | |
2981 | * is non-interruptible, and has no timeout. | |
2982 | * | |
2983 | * This call should be used by drivers that require exclusive access to the | |
2984 | * SPI bus. The SPI bus must be released by a spi_bus_unlock call when the | |
2985 | * exclusive access is over. Data transfer must be done by spi_sync_locked | |
2986 | * and spi_async_locked calls when the SPI bus lock is held. | |
2987 | * | |
97d56dc6 | 2988 | * Return: always zero. |
cf32b71e ES |
2989 | */ |
2990 | int spi_bus_lock(struct spi_master *master) | |
2991 | { | |
2992 | unsigned long flags; | |
2993 | ||
2994 | mutex_lock(&master->bus_lock_mutex); | |
2995 | ||
2996 | spin_lock_irqsave(&master->bus_lock_spinlock, flags); | |
2997 | master->bus_lock_flag = 1; | |
2998 | spin_unlock_irqrestore(&master->bus_lock_spinlock, flags); | |
2999 | ||
3000 | /* mutex remains locked until spi_bus_unlock is called */ | |
3001 | ||
3002 | return 0; | |
3003 | } | |
3004 | EXPORT_SYMBOL_GPL(spi_bus_lock); | |
3005 | ||
3006 | /** | |
3007 | * spi_bus_unlock - release the lock for exclusive SPI bus usage | |
3008 | * @master: SPI bus master that was locked for exclusive bus access | |
3009 | * Context: can sleep | |
3010 | * | |
3011 | * This call may only be used from a context that may sleep. The sleep | |
3012 | * is non-interruptible, and has no timeout. | |
3013 | * | |
3014 | * This call releases an SPI bus lock previously obtained by an spi_bus_lock | |
3015 | * call. | |
3016 | * | |
97d56dc6 | 3017 | * Return: always zero. |
cf32b71e ES |
3018 | */ |
3019 | int spi_bus_unlock(struct spi_master *master) | |
3020 | { | |
3021 | master->bus_lock_flag = 0; | |
3022 | ||
3023 | mutex_unlock(&master->bus_lock_mutex); | |
3024 | ||
3025 | return 0; | |
3026 | } | |
3027 | EXPORT_SYMBOL_GPL(spi_bus_unlock); | |
3028 | ||
a9948b61 | 3029 | /* portable code must never pass more than 32 bytes */ |
5fe5f05e | 3030 | #define SPI_BUFSIZ max(32, SMP_CACHE_BYTES) |
8ae12a0d DB |
3031 | |
3032 | static u8 *buf; | |
3033 | ||
3034 | /** | |
3035 | * spi_write_then_read - SPI synchronous write followed by read | |
3036 | * @spi: device with which data will be exchanged | |
3037 | * @txbuf: data to be written (need not be dma-safe) | |
3038 | * @n_tx: size of txbuf, in bytes | |
27570497 JP |
3039 | * @rxbuf: buffer into which data will be read (need not be dma-safe) |
3040 | * @n_rx: size of rxbuf, in bytes | |
33e34dc6 | 3041 | * Context: can sleep |
8ae12a0d DB |
3042 | * |
3043 | * This performs a half duplex MicroWire style transaction with the | |
3044 | * device, sending txbuf and then reading rxbuf. The return value | |
3045 | * is zero for success, else a negative errno status code. | |
b885244e | 3046 | * This call may only be used from a context that may sleep. |
8ae12a0d | 3047 | * |
0c868461 | 3048 | * Parameters to this routine are always copied using a small buffer; |
33e34dc6 DB |
3049 | * portable code should never use this for more than 32 bytes. |
3050 | * Performance-sensitive or bulk transfer code should instead use | |
0c868461 | 3051 | * spi_{async,sync}() calls with dma-safe buffers. |
97d56dc6 JMC |
3052 | * |
3053 | * Return: zero on success, else a negative error code. | |
8ae12a0d DB |
3054 | */ |
3055 | int spi_write_then_read(struct spi_device *spi, | |
0c4a1590 MB |
3056 | const void *txbuf, unsigned n_tx, |
3057 | void *rxbuf, unsigned n_rx) | |
8ae12a0d | 3058 | { |
068f4070 | 3059 | static DEFINE_MUTEX(lock); |
8ae12a0d DB |
3060 | |
3061 | int status; | |
3062 | struct spi_message message; | |
bdff549e | 3063 | struct spi_transfer x[2]; |
8ae12a0d DB |
3064 | u8 *local_buf; |
3065 | ||
b3a223ee MB |
3066 | /* Use preallocated DMA-safe buffer if we can. We can't avoid |
3067 | * copying here, (as a pure convenience thing), but we can | |
3068 | * keep heap costs out of the hot path unless someone else is | |
3069 | * using the pre-allocated buffer or the transfer is too large. | |
8ae12a0d | 3070 | */ |
b3a223ee | 3071 | if ((n_tx + n_rx) > SPI_BUFSIZ || !mutex_trylock(&lock)) { |
2cd94c8a MB |
3072 | local_buf = kmalloc(max((unsigned)SPI_BUFSIZ, n_tx + n_rx), |
3073 | GFP_KERNEL | GFP_DMA); | |
b3a223ee MB |
3074 | if (!local_buf) |
3075 | return -ENOMEM; | |
3076 | } else { | |
3077 | local_buf = buf; | |
3078 | } | |
8ae12a0d | 3079 | |
8275c642 | 3080 | spi_message_init(&message); |
5fe5f05e | 3081 | memset(x, 0, sizeof(x)); |
bdff549e DB |
3082 | if (n_tx) { |
3083 | x[0].len = n_tx; | |
3084 | spi_message_add_tail(&x[0], &message); | |
3085 | } | |
3086 | if (n_rx) { | |
3087 | x[1].len = n_rx; | |
3088 | spi_message_add_tail(&x[1], &message); | |
3089 | } | |
8275c642 | 3090 | |
8ae12a0d | 3091 | memcpy(local_buf, txbuf, n_tx); |
bdff549e DB |
3092 | x[0].tx_buf = local_buf; |
3093 | x[1].rx_buf = local_buf + n_tx; | |
8ae12a0d DB |
3094 | |
3095 | /* do the i/o */ | |
8ae12a0d | 3096 | status = spi_sync(spi, &message); |
9b938b74 | 3097 | if (status == 0) |
bdff549e | 3098 | memcpy(rxbuf, x[1].rx_buf, n_rx); |
8ae12a0d | 3099 | |
bdff549e | 3100 | if (x[0].tx_buf == buf) |
068f4070 | 3101 | mutex_unlock(&lock); |
8ae12a0d DB |
3102 | else |
3103 | kfree(local_buf); | |
3104 | ||
3105 | return status; | |
3106 | } | |
3107 | EXPORT_SYMBOL_GPL(spi_write_then_read); | |
3108 | ||
3109 | /*-------------------------------------------------------------------------*/ | |
3110 | ||
ce79d54a PA |
3111 | #if IS_ENABLED(CONFIG_OF_DYNAMIC) |
3112 | static int __spi_of_device_match(struct device *dev, void *data) | |
3113 | { | |
3114 | return dev->of_node == data; | |
3115 | } | |
3116 | ||
3117 | /* must call put_device() when done with returned spi_device device */ | |
3118 | static struct spi_device *of_find_spi_device_by_node(struct device_node *node) | |
3119 | { | |
3120 | struct device *dev = bus_find_device(&spi_bus_type, NULL, node, | |
3121 | __spi_of_device_match); | |
3122 | return dev ? to_spi_device(dev) : NULL; | |
3123 | } | |
3124 | ||
3125 | static int __spi_of_master_match(struct device *dev, const void *data) | |
3126 | { | |
3127 | return dev->of_node == data; | |
3128 | } | |
3129 | ||
3130 | /* the spi masters are not using spi_bus, so we find it with another way */ | |
3131 | static struct spi_master *of_find_spi_master_by_node(struct device_node *node) | |
3132 | { | |
3133 | struct device *dev; | |
3134 | ||
3135 | dev = class_find_device(&spi_master_class, NULL, node, | |
3136 | __spi_of_master_match); | |
3137 | if (!dev) | |
3138 | return NULL; | |
3139 | ||
3140 | /* reference got in class_find_device */ | |
3141 | return container_of(dev, struct spi_master, dev); | |
3142 | } | |
3143 | ||
3144 | static int of_spi_notify(struct notifier_block *nb, unsigned long action, | |
3145 | void *arg) | |
3146 | { | |
3147 | struct of_reconfig_data *rd = arg; | |
3148 | struct spi_master *master; | |
3149 | struct spi_device *spi; | |
3150 | ||
3151 | switch (of_reconfig_get_state_change(action, arg)) { | |
3152 | case OF_RECONFIG_CHANGE_ADD: | |
3153 | master = of_find_spi_master_by_node(rd->dn->parent); | |
3154 | if (master == NULL) | |
3155 | return NOTIFY_OK; /* not for us */ | |
3156 | ||
bd6c1644 GU |
3157 | if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { |
3158 | put_device(&master->dev); | |
3159 | return NOTIFY_OK; | |
3160 | } | |
3161 | ||
ce79d54a PA |
3162 | spi = of_register_spi_device(master, rd->dn); |
3163 | put_device(&master->dev); | |
3164 | ||
3165 | if (IS_ERR(spi)) { | |
3166 | pr_err("%s: failed to create for '%s'\n", | |
3167 | __func__, rd->dn->full_name); | |
e0af98a7 | 3168 | of_node_clear_flag(rd->dn, OF_POPULATED); |
ce79d54a PA |
3169 | return notifier_from_errno(PTR_ERR(spi)); |
3170 | } | |
3171 | break; | |
3172 | ||
3173 | case OF_RECONFIG_CHANGE_REMOVE: | |
bd6c1644 GU |
3174 | /* already depopulated? */ |
3175 | if (!of_node_check_flag(rd->dn, OF_POPULATED)) | |
3176 | return NOTIFY_OK; | |
3177 | ||
ce79d54a PA |
3178 | /* find our device by node */ |
3179 | spi = of_find_spi_device_by_node(rd->dn); | |
3180 | if (spi == NULL) | |
3181 | return NOTIFY_OK; /* no? not meant for us */ | |
3182 | ||
3183 | /* unregister takes one ref away */ | |
3184 | spi_unregister_device(spi); | |
3185 | ||
3186 | /* and put the reference of the find */ | |
3187 | put_device(&spi->dev); | |
3188 | break; | |
3189 | } | |
3190 | ||
3191 | return NOTIFY_OK; | |
3192 | } | |
3193 | ||
3194 | static struct notifier_block spi_of_notifier = { | |
3195 | .notifier_call = of_spi_notify, | |
3196 | }; | |
3197 | #else /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ | |
3198 | extern struct notifier_block spi_of_notifier; | |
3199 | #endif /* IS_ENABLED(CONFIG_OF_DYNAMIC) */ | |
3200 | ||
7f24467f OP |
3201 | #if IS_ENABLED(CONFIG_ACPI) |
3202 | static int spi_acpi_master_match(struct device *dev, const void *data) | |
3203 | { | |
3204 | return ACPI_COMPANION(dev->parent) == data; | |
3205 | } | |
3206 | ||
3207 | static int spi_acpi_device_match(struct device *dev, void *data) | |
3208 | { | |
3209 | return ACPI_COMPANION(dev) == data; | |
3210 | } | |
3211 | ||
3212 | static struct spi_master *acpi_spi_find_master_by_adev(struct acpi_device *adev) | |
3213 | { | |
3214 | struct device *dev; | |
3215 | ||
3216 | dev = class_find_device(&spi_master_class, NULL, adev, | |
3217 | spi_acpi_master_match); | |
3218 | if (!dev) | |
3219 | return NULL; | |
3220 | ||
3221 | return container_of(dev, struct spi_master, dev); | |
3222 | } | |
3223 | ||
3224 | static struct spi_device *acpi_spi_find_device_by_adev(struct acpi_device *adev) | |
3225 | { | |
3226 | struct device *dev; | |
3227 | ||
3228 | dev = bus_find_device(&spi_bus_type, NULL, adev, spi_acpi_device_match); | |
3229 | ||
3230 | return dev ? to_spi_device(dev) : NULL; | |
3231 | } | |
3232 | ||
3233 | static int acpi_spi_notify(struct notifier_block *nb, unsigned long value, | |
3234 | void *arg) | |
3235 | { | |
3236 | struct acpi_device *adev = arg; | |
3237 | struct spi_master *master; | |
3238 | struct spi_device *spi; | |
3239 | ||
3240 | switch (value) { | |
3241 | case ACPI_RECONFIG_DEVICE_ADD: | |
3242 | master = acpi_spi_find_master_by_adev(adev->parent); | |
3243 | if (!master) | |
3244 | break; | |
3245 | ||
3246 | acpi_register_spi_device(master, adev); | |
3247 | put_device(&master->dev); | |
3248 | break; | |
3249 | case ACPI_RECONFIG_DEVICE_REMOVE: | |
3250 | if (!acpi_device_enumerated(adev)) | |
3251 | break; | |
3252 | ||
3253 | spi = acpi_spi_find_device_by_adev(adev); | |
3254 | if (!spi) | |
3255 | break; | |
3256 | ||
3257 | spi_unregister_device(spi); | |
3258 | put_device(&spi->dev); | |
3259 | break; | |
3260 | } | |
3261 | ||
3262 | return NOTIFY_OK; | |
3263 | } | |
3264 | ||
3265 | static struct notifier_block spi_acpi_notifier = { | |
3266 | .notifier_call = acpi_spi_notify, | |
3267 | }; | |
3268 | #else | |
3269 | extern struct notifier_block spi_acpi_notifier; | |
3270 | #endif | |
3271 | ||
8ae12a0d DB |
3272 | static int __init spi_init(void) |
3273 | { | |
b885244e DB |
3274 | int status; |
3275 | ||
e94b1766 | 3276 | buf = kmalloc(SPI_BUFSIZ, GFP_KERNEL); |
b885244e DB |
3277 | if (!buf) { |
3278 | status = -ENOMEM; | |
3279 | goto err0; | |
3280 | } | |
3281 | ||
3282 | status = bus_register(&spi_bus_type); | |
3283 | if (status < 0) | |
3284 | goto err1; | |
8ae12a0d | 3285 | |
b885244e DB |
3286 | status = class_register(&spi_master_class); |
3287 | if (status < 0) | |
3288 | goto err2; | |
ce79d54a | 3289 | |
5267720e | 3290 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
ce79d54a | 3291 | WARN_ON(of_reconfig_notifier_register(&spi_of_notifier)); |
7f24467f OP |
3292 | if (IS_ENABLED(CONFIG_ACPI)) |
3293 | WARN_ON(acpi_reconfig_notifier_register(&spi_acpi_notifier)); | |
ce79d54a | 3294 | |
8ae12a0d | 3295 | return 0; |
b885244e DB |
3296 | |
3297 | err2: | |
3298 | bus_unregister(&spi_bus_type); | |
3299 | err1: | |
3300 | kfree(buf); | |
3301 | buf = NULL; | |
3302 | err0: | |
3303 | return status; | |
8ae12a0d | 3304 | } |
b885244e | 3305 | |
8ae12a0d DB |
3306 | /* board_info is normally registered in arch_initcall(), |
3307 | * but even essential drivers wait till later | |
b885244e DB |
3308 | * |
3309 | * REVISIT only boardinfo really needs static linking. the rest (device and | |
3310 | * driver registration) _could_ be dynamically linked (modular) ... costs | |
3311 | * include needing to have boardinfo data structures be much more public. | |
8ae12a0d | 3312 | */ |
673c0c00 | 3313 | postcore_initcall(spi_init); |
8ae12a0d | 3314 |