]>
Commit | Line | Data |
---|---|---|
d29389de | 1 | /* |
ca632f55 | 2 | * SPI master driver using generic bitbanged GPIO |
d29389de DB |
3 | * |
4 | * Copyright (C) 2006,2008 David Brownell | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License as published by | |
8 | * the Free Software Foundation; either version 2 of the License, or | |
9 | * (at your option) any later version. | |
10 | * | |
11 | * This program is distributed in the hope that it will be useful, | |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | * GNU General Public License for more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * along with this program; if not, write to the Free Software | |
18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
19 | */ | |
20 | #include <linux/kernel.h> | |
d7614de4 | 21 | #include <linux/module.h> |
d29389de DB |
22 | #include <linux/init.h> |
23 | #include <linux/platform_device.h> | |
24 | #include <linux/gpio.h> | |
38ab18ca DM |
25 | #include <linux/of_device.h> |
26 | #include <linux/of_gpio.h> | |
d29389de DB |
27 | |
28 | #include <linux/spi/spi.h> | |
29 | #include <linux/spi/spi_bitbang.h> | |
30 | #include <linux/spi/spi_gpio.h> | |
31 | ||
32 | ||
33 | /* | |
34 | * This bitbanging SPI master driver should help make systems usable | |
35 | * when a native hardware SPI engine is not available, perhaps because | |
36 | * its driver isn't yet working or because the I/O pins it requires | |
37 | * are used for other purposes. | |
38 | * | |
39 | * platform_device->driver_data ... points to spi_gpio | |
40 | * | |
41 | * spi->controller_state ... reserved for bitbang framework code | |
42 | * spi->controller_data ... holds chipselect GPIO | |
43 | * | |
44 | * spi->master->dev.driver_data ... points to spi_gpio->bitbang | |
45 | */ | |
46 | ||
47 | struct spi_gpio { | |
48 | struct spi_bitbang bitbang; | |
49 | struct spi_gpio_platform_data pdata; | |
50 | struct platform_device *pdev; | |
161c2dd3 | 51 | int cs_gpios[0]; |
d29389de DB |
52 | }; |
53 | ||
54 | /*----------------------------------------------------------------------*/ | |
55 | ||
56 | /* | |
57 | * Because the overhead of going through four GPIO procedure calls | |
58 | * per transferred bit can make performance a problem, this code | |
59 | * is set up so that you can use it in either of two ways: | |
60 | * | |
61 | * - The slow generic way: set up platform_data to hold the GPIO | |
62 | * numbers used for MISO/MOSI/SCK, and issue procedure calls for | |
63 | * each of them. This driver can handle several such busses. | |
64 | * | |
65 | * - The quicker inlined way: only helps with platform GPIO code | |
66 | * that inlines operations for constant GPIOs. This can give | |
67 | * you tight (fast!) inner loops, but each such bus needs a | |
68 | * new driver. You'll define a new C file, with Makefile and | |
69 | * Kconfig support; the C code can be a total of six lines: | |
70 | * | |
71 | * #define DRIVER_NAME "myboard_spi2" | |
72 | * #define SPI_MISO_GPIO 119 | |
73 | * #define SPI_MOSI_GPIO 120 | |
74 | * #define SPI_SCK_GPIO 121 | |
75 | * #define SPI_N_CHIPSEL 4 | |
ca632f55 | 76 | * #include "spi-gpio.c" |
d29389de DB |
77 | */ |
78 | ||
79 | #ifndef DRIVER_NAME | |
80 | #define DRIVER_NAME "spi_gpio" | |
81 | ||
82 | #define GENERIC_BITBANG /* vs tight inlines */ | |
83 | ||
84 | /* all functions referencing these symbols must define pdata */ | |
85 | #define SPI_MISO_GPIO ((pdata)->miso) | |
86 | #define SPI_MOSI_GPIO ((pdata)->mosi) | |
87 | #define SPI_SCK_GPIO ((pdata)->sck) | |
88 | ||
89 | #define SPI_N_CHIPSEL ((pdata)->num_chipselect) | |
90 | ||
91 | #endif | |
92 | ||
93 | /*----------------------------------------------------------------------*/ | |
94 | ||
161c2dd3 DM |
95 | static inline struct spi_gpio * __pure |
96 | spi_to_spi_gpio(const struct spi_device *spi) | |
d29389de DB |
97 | { |
98 | const struct spi_bitbang *bang; | |
161c2dd3 | 99 | struct spi_gpio *spi_gpio; |
d29389de DB |
100 | |
101 | bang = spi_master_get_devdata(spi->master); | |
102 | spi_gpio = container_of(bang, struct spi_gpio, bitbang); | |
161c2dd3 DM |
103 | return spi_gpio; |
104 | } | |
105 | ||
106 | static inline struct spi_gpio_platform_data * __pure | |
107 | spi_to_pdata(const struct spi_device *spi) | |
108 | { | |
109 | return &spi_to_spi_gpio(spi)->pdata; | |
d29389de DB |
110 | } |
111 | ||
112 | /* this is #defined to avoid unused-variable warnings when inlining */ | |
113 | #define pdata spi_to_pdata(spi) | |
114 | ||
115 | static inline void setsck(const struct spi_device *spi, int is_on) | |
116 | { | |
117 | gpio_set_value(SPI_SCK_GPIO, is_on); | |
118 | } | |
119 | ||
120 | static inline void setmosi(const struct spi_device *spi, int is_on) | |
121 | { | |
122 | gpio_set_value(SPI_MOSI_GPIO, is_on); | |
123 | } | |
124 | ||
125 | static inline int getmiso(const struct spi_device *spi) | |
126 | { | |
be50344e | 127 | return !!gpio_get_value(SPI_MISO_GPIO); |
d29389de DB |
128 | } |
129 | ||
130 | #undef pdata | |
131 | ||
132 | /* | |
133 | * NOTE: this clocks "as fast as we can". It "should" be a function of the | |
134 | * requested device clock. Software overhead means we usually have trouble | |
135 | * reaching even one Mbit/sec (except when we can inline bitops), so for now | |
136 | * we'll just assume we never need additional per-bit slowdowns. | |
137 | */ | |
138 | #define spidelay(nsecs) do {} while (0) | |
139 | ||
ca632f55 | 140 | #include "spi-bitbang-txrx.h" |
d29389de DB |
141 | |
142 | /* | |
143 | * These functions can leverage inline expansion of GPIO calls to shrink | |
144 | * costs for a txrx bit, often by factors of around ten (by instruction | |
145 | * count). That is particularly visible for larger word sizes, but helps | |
146 | * even with default 8-bit words. | |
147 | * | |
148 | * REVISIT overheads calling these functions for each word also have | |
149 | * significant performance costs. Having txrx_bufs() calls that inline | |
150 | * the txrx_word() logic would help performance, e.g. on larger blocks | |
151 | * used with flash storage or MMC/SD. There should also be ways to make | |
152 | * GCC be less stupid about reloading registers inside the I/O loops, | |
153 | * even without inlined GPIO calls; __attribute__((hot)) on GCC 4.3? | |
154 | */ | |
155 | ||
156 | static u32 spi_gpio_txrx_word_mode0(struct spi_device *spi, | |
157 | unsigned nsecs, u32 word, u8 bits) | |
158 | { | |
04bb2a03 | 159 | return bitbang_txrx_be_cpha0(spi, nsecs, 0, 0, word, bits); |
d29389de DB |
160 | } |
161 | ||
162 | static u32 spi_gpio_txrx_word_mode1(struct spi_device *spi, | |
163 | unsigned nsecs, u32 word, u8 bits) | |
164 | { | |
04bb2a03 | 165 | return bitbang_txrx_be_cpha1(spi, nsecs, 0, 0, word, bits); |
d29389de DB |
166 | } |
167 | ||
168 | static u32 spi_gpio_txrx_word_mode2(struct spi_device *spi, | |
169 | unsigned nsecs, u32 word, u8 bits) | |
170 | { | |
04bb2a03 | 171 | return bitbang_txrx_be_cpha0(spi, nsecs, 1, 0, word, bits); |
d29389de DB |
172 | } |
173 | ||
174 | static u32 spi_gpio_txrx_word_mode3(struct spi_device *spi, | |
175 | unsigned nsecs, u32 word, u8 bits) | |
176 | { | |
04bb2a03 | 177 | return bitbang_txrx_be_cpha1(spi, nsecs, 1, 0, word, bits); |
d29389de DB |
178 | } |
179 | ||
3c8e1a84 MS |
180 | /* |
181 | * These functions do not call setmosi or getmiso if respective flag | |
182 | * (SPI_MASTER_NO_RX or SPI_MASTER_NO_TX) is set, so they are safe to | |
183 | * call when such pin is not present or defined in the controller. | |
184 | * A separate set of callbacks is defined to get highest possible | |
185 | * speed in the generic case (when both MISO and MOSI lines are | |
186 | * available), as optimiser will remove the checks when argument is | |
187 | * constant. | |
188 | */ | |
189 | ||
190 | static u32 spi_gpio_spec_txrx_word_mode0(struct spi_device *spi, | |
191 | unsigned nsecs, u32 word, u8 bits) | |
192 | { | |
193 | unsigned flags = spi->master->flags; | |
194 | return bitbang_txrx_be_cpha0(spi, nsecs, 0, flags, word, bits); | |
195 | } | |
196 | ||
197 | static u32 spi_gpio_spec_txrx_word_mode1(struct spi_device *spi, | |
198 | unsigned nsecs, u32 word, u8 bits) | |
199 | { | |
200 | unsigned flags = spi->master->flags; | |
201 | return bitbang_txrx_be_cpha1(spi, nsecs, 0, flags, word, bits); | |
202 | } | |
203 | ||
204 | static u32 spi_gpio_spec_txrx_word_mode2(struct spi_device *spi, | |
205 | unsigned nsecs, u32 word, u8 bits) | |
206 | { | |
207 | unsigned flags = spi->master->flags; | |
208 | return bitbang_txrx_be_cpha0(spi, nsecs, 1, flags, word, bits); | |
209 | } | |
210 | ||
211 | static u32 spi_gpio_spec_txrx_word_mode3(struct spi_device *spi, | |
212 | unsigned nsecs, u32 word, u8 bits) | |
213 | { | |
214 | unsigned flags = spi->master->flags; | |
215 | return bitbang_txrx_be_cpha1(spi, nsecs, 1, flags, word, bits); | |
216 | } | |
217 | ||
d29389de DB |
218 | /*----------------------------------------------------------------------*/ |
219 | ||
220 | static void spi_gpio_chipselect(struct spi_device *spi, int is_active) | |
221 | { | |
161c2dd3 DM |
222 | struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); |
223 | unsigned int cs = spi_gpio->cs_gpios[spi->chip_select]; | |
d29389de DB |
224 | |
225 | /* set initial clock polarity */ | |
226 | if (is_active) | |
227 | setsck(spi, spi->mode & SPI_CPOL); | |
228 | ||
bfb9bcdb MB |
229 | if (cs != SPI_GPIO_NO_CHIPSELECT) { |
230 | /* SPI is normally active-low */ | |
231 | gpio_set_value(cs, (spi->mode & SPI_CS_HIGH) ? is_active : !is_active); | |
232 | } | |
d29389de DB |
233 | } |
234 | ||
235 | static int spi_gpio_setup(struct spi_device *spi) | |
236 | { | |
38ab18ca | 237 | unsigned int cs; |
161c2dd3 DM |
238 | int status = 0; |
239 | struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); | |
38ab18ca | 240 | struct device_node *np = spi->master->dev.of_node; |
d29389de | 241 | |
38ab18ca DM |
242 | if (np) { |
243 | /* | |
244 | * In DT environments, the CS GPIOs have already been | |
245 | * initialized from the "cs-gpios" property of the node. | |
246 | */ | |
247 | cs = spi_gpio->cs_gpios[spi->chip_select]; | |
248 | } else { | |
249 | /* | |
250 | * ... otherwise, take it from spi->controller_data | |
251 | */ | |
252 | cs = (unsigned int) spi->controller_data; | |
253 | } | |
254 | ||
d29389de | 255 | if (!spi->controller_state) { |
bfb9bcdb MB |
256 | if (cs != SPI_GPIO_NO_CHIPSELECT) { |
257 | status = gpio_request(cs, dev_name(&spi->dev)); | |
258 | if (status) | |
259 | return status; | |
05644147 UKK |
260 | status = gpio_direction_output(cs, |
261 | !(spi->mode & SPI_CS_HIGH)); | |
bfb9bcdb | 262 | } |
d29389de | 263 | } |
161c2dd3 | 264 | if (!status) { |
38ab18ca | 265 | /* in case it was initialized from static board data */ |
161c2dd3 | 266 | spi_gpio->cs_gpios[spi->chip_select] = cs; |
6b8cc330 | 267 | status = spi_bitbang_setup(spi); |
161c2dd3 DM |
268 | } |
269 | ||
d29389de | 270 | if (status) { |
bfb9bcdb | 271 | if (!spi->controller_state && cs != SPI_GPIO_NO_CHIPSELECT) |
d29389de DB |
272 | gpio_free(cs); |
273 | } | |
274 | return status; | |
275 | } | |
276 | ||
277 | static void spi_gpio_cleanup(struct spi_device *spi) | |
278 | { | |
161c2dd3 DM |
279 | struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi); |
280 | unsigned int cs = spi_gpio->cs_gpios[spi->chip_select]; | |
d29389de | 281 | |
bfb9bcdb MB |
282 | if (cs != SPI_GPIO_NO_CHIPSELECT) |
283 | gpio_free(cs); | |
d29389de DB |
284 | spi_bitbang_cleanup(spi); |
285 | } | |
286 | ||
fd4a319b | 287 | static int spi_gpio_alloc(unsigned pin, const char *label, bool is_in) |
d29389de DB |
288 | { |
289 | int value; | |
290 | ||
291 | value = gpio_request(pin, label); | |
292 | if (value == 0) { | |
293 | if (is_in) | |
294 | value = gpio_direction_input(pin); | |
295 | else | |
296 | value = gpio_direction_output(pin, 0); | |
297 | } | |
298 | return value; | |
299 | } | |
300 | ||
fd4a319b GL |
301 | static int spi_gpio_request(struct spi_gpio_platform_data *pdata, |
302 | const char *label, u16 *res_flags) | |
d29389de DB |
303 | { |
304 | int value; | |
305 | ||
306 | /* NOTE: SPI_*_GPIO symbols may reference "pdata" */ | |
307 | ||
3c8e1a84 MS |
308 | if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) { |
309 | value = spi_gpio_alloc(SPI_MOSI_GPIO, label, false); | |
310 | if (value) | |
311 | goto done; | |
312 | } else { | |
313 | /* HW configuration without MOSI pin */ | |
314 | *res_flags |= SPI_MASTER_NO_TX; | |
315 | } | |
d29389de | 316 | |
3c8e1a84 MS |
317 | if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) { |
318 | value = spi_gpio_alloc(SPI_MISO_GPIO, label, true); | |
319 | if (value) | |
320 | goto free_mosi; | |
321 | } else { | |
322 | /* HW configuration without MISO pin */ | |
323 | *res_flags |= SPI_MASTER_NO_RX; | |
324 | } | |
d29389de DB |
325 | |
326 | value = spi_gpio_alloc(SPI_SCK_GPIO, label, false); | |
327 | if (value) | |
328 | goto free_miso; | |
329 | ||
330 | goto done; | |
331 | ||
332 | free_miso: | |
3c8e1a84 MS |
333 | if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) |
334 | gpio_free(SPI_MISO_GPIO); | |
d29389de | 335 | free_mosi: |
3c8e1a84 MS |
336 | if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) |
337 | gpio_free(SPI_MOSI_GPIO); | |
d29389de DB |
338 | done: |
339 | return value; | |
340 | } | |
341 | ||
38ab18ca DM |
342 | #ifdef CONFIG_OF |
343 | static struct of_device_id spi_gpio_dt_ids[] = { | |
344 | { .compatible = "spi-gpio" }, | |
345 | {} | |
346 | }; | |
347 | MODULE_DEVICE_TABLE(of, spi_gpio_dt_ids); | |
348 | ||
349 | static int spi_gpio_probe_dt(struct platform_device *pdev) | |
350 | { | |
351 | int ret; | |
352 | u32 tmp; | |
353 | struct spi_gpio_platform_data *pdata; | |
354 | struct device_node *np = pdev->dev.of_node; | |
355 | const struct of_device_id *of_id = | |
356 | of_match_device(spi_gpio_dt_ids, &pdev->dev); | |
357 | ||
358 | if (!of_id) | |
359 | return 0; | |
360 | ||
361 | pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); | |
362 | if (!pdata) | |
363 | return -ENOMEM; | |
364 | ||
0202a32d MR |
365 | ret = of_get_named_gpio(np, "gpio-sck", 0); |
366 | if (ret < 0) { | |
367 | dev_err(&pdev->dev, "gpio-sck property not found\n"); | |
368 | goto error_free; | |
369 | } | |
370 | pdata->sck = ret; | |
371 | ||
372 | ret = of_get_named_gpio(np, "gpio-miso", 0); | |
373 | if (ret < 0) { | |
374 | dev_info(&pdev->dev, "gpio-miso property not found, switching to no-rx mode\n"); | |
375 | pdata->miso = SPI_GPIO_NO_MISO; | |
376 | } else | |
377 | pdata->miso = ret; | |
378 | ||
379 | ret = of_get_named_gpio(np, "gpio-mosi", 0); | |
380 | if (ret < 0) { | |
381 | dev_info(&pdev->dev, "gpio-mosi property not found, switching to no-tx mode\n"); | |
382 | pdata->mosi = SPI_GPIO_NO_MOSI; | |
383 | } else | |
384 | pdata->mosi = ret; | |
38ab18ca DM |
385 | |
386 | ret = of_property_read_u32(np, "num-chipselects", &tmp); | |
387 | if (ret < 0) { | |
388 | dev_err(&pdev->dev, "num-chipselects property not found\n"); | |
389 | goto error_free; | |
390 | } | |
391 | ||
392 | pdata->num_chipselect = tmp; | |
393 | pdev->dev.platform_data = pdata; | |
394 | ||
395 | return 1; | |
396 | ||
397 | error_free: | |
398 | devm_kfree(&pdev->dev, pdata); | |
399 | return ret; | |
400 | } | |
401 | #else | |
ac2cb30b | 402 | static inline int spi_gpio_probe_dt(struct platform_device *pdev) |
38ab18ca DM |
403 | { |
404 | return 0; | |
405 | } | |
406 | #endif | |
407 | ||
fd4a319b | 408 | static int spi_gpio_probe(struct platform_device *pdev) |
d29389de DB |
409 | { |
410 | int status; | |
411 | struct spi_master *master; | |
412 | struct spi_gpio *spi_gpio; | |
413 | struct spi_gpio_platform_data *pdata; | |
3c8e1a84 | 414 | u16 master_flags = 0; |
38ab18ca DM |
415 | bool use_of = 0; |
416 | ||
417 | status = spi_gpio_probe_dt(pdev); | |
418 | if (status < 0) | |
419 | return status; | |
420 | if (status > 0) | |
421 | use_of = 1; | |
d29389de | 422 | |
8074cf06 | 423 | pdata = dev_get_platdata(&pdev->dev); |
d29389de DB |
424 | #ifdef GENERIC_BITBANG |
425 | if (!pdata || !pdata->num_chipselect) | |
426 | return -ENODEV; | |
427 | #endif | |
428 | ||
3c8e1a84 | 429 | status = spi_gpio_request(pdata, dev_name(&pdev->dev), &master_flags); |
d29389de DB |
430 | if (status < 0) |
431 | return status; | |
432 | ||
161c2dd3 DM |
433 | master = spi_alloc_master(&pdev->dev, sizeof(*spi_gpio) + |
434 | (sizeof(int) * SPI_N_CHIPSEL)); | |
d29389de DB |
435 | if (!master) { |
436 | status = -ENOMEM; | |
437 | goto gpio_free; | |
438 | } | |
439 | spi_gpio = spi_master_get_devdata(master); | |
440 | platform_set_drvdata(pdev, spi_gpio); | |
441 | ||
442 | spi_gpio->pdev = pdev; | |
443 | if (pdata) | |
444 | spi_gpio->pdata = *pdata; | |
445 | ||
24778be2 | 446 | master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32); |
3c8e1a84 | 447 | master->flags = master_flags; |
d29389de DB |
448 | master->bus_num = pdev->id; |
449 | master->num_chipselect = SPI_N_CHIPSEL; | |
450 | master->setup = spi_gpio_setup; | |
451 | master->cleanup = spi_gpio_cleanup; | |
38ab18ca DM |
452 | #ifdef CONFIG_OF |
453 | master->dev.of_node = pdev->dev.of_node; | |
454 | ||
455 | if (use_of) { | |
456 | int i; | |
457 | struct device_node *np = pdev->dev.of_node; | |
458 | ||
459 | /* | |
460 | * In DT environments, take the CS GPIO from the "cs-gpios" | |
461 | * property of the node. | |
462 | */ | |
463 | ||
464 | for (i = 0; i < SPI_N_CHIPSEL; i++) | |
465 | spi_gpio->cs_gpios[i] = | |
466 | of_get_named_gpio(np, "cs-gpios", i); | |
467 | } | |
468 | #endif | |
d29389de DB |
469 | |
470 | spi_gpio->bitbang.master = spi_master_get(master); | |
471 | spi_gpio->bitbang.chipselect = spi_gpio_chipselect; | |
3c8e1a84 | 472 | |
23699f98 | 473 | if ((master_flags & (SPI_MASTER_NO_TX | SPI_MASTER_NO_RX)) == 0) { |
3c8e1a84 MS |
474 | spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0; |
475 | spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_txrx_word_mode1; | |
476 | spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_txrx_word_mode2; | |
477 | spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_txrx_word_mode3; | |
478 | } else { | |
479 | spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_spec_txrx_word_mode0; | |
480 | spi_gpio->bitbang.txrx_word[SPI_MODE_1] = spi_gpio_spec_txrx_word_mode1; | |
481 | spi_gpio->bitbang.txrx_word[SPI_MODE_2] = spi_gpio_spec_txrx_word_mode2; | |
482 | spi_gpio->bitbang.txrx_word[SPI_MODE_3] = spi_gpio_spec_txrx_word_mode3; | |
483 | } | |
d29389de DB |
484 | spi_gpio->bitbang.setup_transfer = spi_bitbang_setup_transfer; |
485 | spi_gpio->bitbang.flags = SPI_CS_HIGH; | |
486 | ||
487 | status = spi_bitbang_start(&spi_gpio->bitbang); | |
488 | if (status < 0) { | |
489 | spi_master_put(spi_gpio->bitbang.master); | |
490 | gpio_free: | |
3c8e1a84 MS |
491 | if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) |
492 | gpio_free(SPI_MISO_GPIO); | |
493 | if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) | |
494 | gpio_free(SPI_MOSI_GPIO); | |
d29389de DB |
495 | gpio_free(SPI_SCK_GPIO); |
496 | spi_master_put(master); | |
497 | } | |
498 | ||
499 | return status; | |
500 | } | |
501 | ||
fd4a319b | 502 | static int spi_gpio_remove(struct platform_device *pdev) |
d29389de DB |
503 | { |
504 | struct spi_gpio *spi_gpio; | |
505 | struct spi_gpio_platform_data *pdata; | |
506 | int status; | |
507 | ||
508 | spi_gpio = platform_get_drvdata(pdev); | |
8074cf06 | 509 | pdata = dev_get_platdata(&pdev->dev); |
d29389de DB |
510 | |
511 | /* stop() unregisters child devices too */ | |
512 | status = spi_bitbang_stop(&spi_gpio->bitbang); | |
513 | spi_master_put(spi_gpio->bitbang.master); | |
514 | ||
3c8e1a84 MS |
515 | if (SPI_MISO_GPIO != SPI_GPIO_NO_MISO) |
516 | gpio_free(SPI_MISO_GPIO); | |
517 | if (SPI_MOSI_GPIO != SPI_GPIO_NO_MOSI) | |
518 | gpio_free(SPI_MOSI_GPIO); | |
d29389de DB |
519 | gpio_free(SPI_SCK_GPIO); |
520 | ||
521 | return status; | |
522 | } | |
523 | ||
524 | MODULE_ALIAS("platform:" DRIVER_NAME); | |
525 | ||
526 | static struct platform_driver spi_gpio_driver = { | |
38ab18ca DM |
527 | .driver = { |
528 | .name = DRIVER_NAME, | |
529 | .owner = THIS_MODULE, | |
530 | .of_match_table = of_match_ptr(spi_gpio_dt_ids), | |
531 | }, | |
940ab889 | 532 | .probe = spi_gpio_probe, |
fd4a319b | 533 | .remove = spi_gpio_remove, |
d29389de | 534 | }; |
940ab889 | 535 | module_platform_driver(spi_gpio_driver); |
d29389de DB |
536 | |
537 | MODULE_DESCRIPTION("SPI master driver using generic bitbanged GPIO "); | |
538 | MODULE_AUTHOR("David Brownell"); | |
539 | MODULE_LICENSE("GPL"); |