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Commit | Line | Data |
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ffa458c1 DB |
1 | /* |
2 | * ADS7846 based touchscreen and sensor driver | |
3 | * | |
4 | * Copyright (c) 2005 David Brownell | |
7de90a8c ID |
5 | * Copyright (c) 2006 Nokia Corporation |
6 | * Various changes: Imre Deak <imre.deak@nokia.com> | |
ffa458c1 DB |
7 | * |
8 | * Using code from: | |
9 | * - corgi_ts.c | |
10 | * Copyright (C) 2004-2005 Richard Purdie | |
11 | * - omap_ts.[hc], ads7846.h, ts_osk.c | |
12 | * Copyright (C) 2002 MontaVista Software | |
13 | * Copyright (C) 2004 Texas Instruments | |
14 | * Copyright (C) 2005 Dirk Behme | |
15 | * | |
16 | * This program is free software; you can redistribute it and/or modify | |
17 | * it under the terms of the GNU General Public License version 2 as | |
18 | * published by the Free Software Foundation. | |
19 | */ | |
2991a1ca | 20 | #include <linux/types.h> |
2c8dc071 | 21 | #include <linux/hwmon.h> |
ffa458c1 | 22 | #include <linux/init.h> |
2c8dc071 | 23 | #include <linux/err.h> |
2991a1ca | 24 | #include <linux/sched.h> |
ffa458c1 DB |
25 | #include <linux/delay.h> |
26 | #include <linux/input.h> | |
27 | #include <linux/interrupt.h> | |
28 | #include <linux/slab.h> | |
3c36e719 | 29 | #include <linux/pm.h> |
4d5975e5 | 30 | #include <linux/gpio.h> |
ffa458c1 DB |
31 | #include <linux/spi/spi.h> |
32 | #include <linux/spi/ads7846.h> | |
91143379 | 33 | #include <linux/regulator/consumer.h> |
d2d8442d | 34 | #include <linux/module.h> |
3ac8bf07 | 35 | #include <asm/irq.h> |
ffa458c1 | 36 | |
ffa458c1 | 37 | /* |
9084533e | 38 | * This code has been heavily tested on a Nokia 770, and lightly |
52ce4eaa | 39 | * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). |
bff0de5f | 40 | * TSC2046 is just newer ads7846 silicon. |
969111e9 NF |
41 | * Support for ads7843 tested on Atmel at91sam926x-EK. |
42 | * Support for ads7845 has only been stubbed in. | |
06a09124 | 43 | * Support for Analog Devices AD7873 and AD7843 tested. |
ffa458c1 | 44 | * |
7de90a8c ID |
45 | * IRQ handling needs a workaround because of a shortcoming in handling |
46 | * edge triggered IRQs on some platforms like the OMAP1/2. These | |
47 | * platforms don't handle the ARM lazy IRQ disabling properly, thus we | |
48 | * have to maintain our own SW IRQ disabled status. This should be | |
49 | * removed as soon as the affected platform's IRQ handling is fixed. | |
50 | * | |
52ce4eaa | 51 | * App note sbaa036 talks in more detail about accurate sampling... |
ffa458c1 DB |
52 | * that ought to help in situations like LCDs inducing noise (which |
53 | * can also be helped by using synch signals) and more generally. | |
7de90a8c ID |
54 | * This driver tries to utilize the measures described in the app |
55 | * note. The strength of filtering can be set in the board-* specific | |
56 | * files. | |
ffa458c1 DB |
57 | */ |
58 | ||
2991a1ca JW |
59 | #define TS_POLL_DELAY 1 /* ms delay before the first sample */ |
60 | #define TS_POLL_PERIOD 5 /* ms delay between samples */ | |
ffa458c1 | 61 | |
d93f70b2 DB |
62 | /* this driver doesn't aim at the peak continuous sample rate */ |
63 | #define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) | |
64 | ||
ffa458c1 | 65 | struct ts_event { |
2991a1ca JW |
66 | /* |
67 | * For portability, we can't read 12 bit values using SPI (which | |
68 | * would make the controller deliver them as native byte order u16 | |
d93f70b2 | 69 | * with msbs zeroed). Instead, we read them as two 8-bit values, |
da970e69 | 70 | * *** WHICH NEED BYTESWAPPING *** and range adjustment. |
ffa458c1 | 71 | */ |
da970e69 ID |
72 | u16 x; |
73 | u16 y; | |
74 | u16 z1, z2; | |
2991a1ca | 75 | bool ignore; |
3eac5c7e AG |
76 | u8 x_buf[3]; |
77 | u8 y_buf[3]; | |
ffa458c1 DB |
78 | }; |
79 | ||
e8f462d2 DT |
80 | /* |
81 | * We allocate this separately to avoid cache line sharing issues when | |
82 | * driver is used with DMA-based SPI controllers (like atmel_spi) on | |
83 | * systems where main memory is not DMA-coherent (most non-x86 boards). | |
84 | */ | |
85 | struct ads7846_packet { | |
86 | u8 read_x, read_y, read_z1, read_z2, pwrdown; | |
87 | u16 dummy; /* for the pwrdown read */ | |
88 | struct ts_event tc; | |
3eac5c7e AG |
89 | /* for ads7845 with mpc5121 psc spi we use 3-byte buffers */ |
90 | u8 read_x_cmd[3], read_y_cmd[3], pwrdown_cmd[3]; | |
e8f462d2 DT |
91 | }; |
92 | ||
ffa458c1 | 93 | struct ads7846 { |
a90f7e98 | 94 | struct input_dev *input; |
ffa458c1 | 95 | char phys[32]; |
b58895f8 | 96 | char name[32]; |
ffa458c1 DB |
97 | |
98 | struct spi_device *spi; | |
91143379 | 99 | struct regulator *reg; |
2c8dc071 DB |
100 | |
101 | #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) | |
8dd51650 | 102 | struct attribute_group *attr_group; |
1beeffe4 | 103 | struct device *hwmon; |
2c8dc071 DB |
104 | #endif |
105 | ||
ffa458c1 | 106 | u16 model; |
7c6d0ee1 | 107 | u16 vref_mv; |
ffa458c1 DB |
108 | u16 vref_delay_usecs; |
109 | u16 x_plate_ohms; | |
d5b415c9 | 110 | u16 pressure_max; |
ffa458c1 | 111 | |
86579a4c | 112 | bool swap_xy; |
ebcaaad9 | 113 | bool use_internal; |
86579a4c | 114 | |
e8f462d2 | 115 | struct ads7846_packet *packet; |
ffa458c1 | 116 | |
e4f48861 | 117 | struct spi_transfer xfer[18]; |
0b7018aa | 118 | struct spi_message msg[5]; |
2991a1ca JW |
119 | int msg_count; |
120 | wait_queue_head_t wait; | |
121 | ||
122 | bool pendown; | |
123 | ||
0b7018aa | 124 | int read_cnt; |
d5b415c9 | 125 | int read_rep; |
0b7018aa ID |
126 | int last_read; |
127 | ||
128 | u16 debounce_max; | |
129 | u16 debounce_tol; | |
d5b415c9 | 130 | u16 debounce_rep; |
ffa458c1 | 131 | |
1d25891f SH |
132 | u16 penirq_recheck_delay_usecs; |
133 | ||
2991a1ca JW |
134 | struct mutex lock; |
135 | bool stopped; /* P: lock */ | |
136 | bool disabled; /* P: lock */ | |
137 | bool suspended; /* P: lock */ | |
c9e617a5 | 138 | |
da970e69 ID |
139 | int (*filter)(void *data, int data_idx, int *val); |
140 | void *filter_data; | |
141 | void (*filter_cleanup)(void *data); | |
c9e617a5 | 142 | int (*get_pendown_state)(void); |
4d5975e5 | 143 | int gpio_pendown; |
fd746d54 EM |
144 | |
145 | void (*wait_for_sync)(void); | |
ffa458c1 DB |
146 | }; |
147 | ||
148 | /* leave chip selected when we're done, for quicker re-select? */ | |
149 | #if 0 | |
150 | #define CS_CHANGE(xfer) ((xfer).cs_change = 1) | |
151 | #else | |
152 | #define CS_CHANGE(xfer) ((xfer).cs_change = 0) | |
153 | #endif | |
154 | ||
155 | /*--------------------------------------------------------------------------*/ | |
156 | ||
157 | /* The ADS7846 has touchscreen and other sensors. | |
158 | * Earlier ads784x chips are somewhat compatible. | |
159 | */ | |
160 | #define ADS_START (1 << 7) | |
161 | #define ADS_A2A1A0_d_y (1 << 4) /* differential */ | |
162 | #define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ | |
163 | #define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ | |
164 | #define ADS_A2A1A0_d_x (5 << 4) /* differential */ | |
165 | #define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ | |
166 | #define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ | |
167 | #define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ | |
168 | #define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ | |
169 | #define ADS_8_BIT (1 << 3) | |
170 | #define ADS_12_BIT (0 << 3) | |
171 | #define ADS_SER (1 << 2) /* non-differential */ | |
172 | #define ADS_DFR (0 << 2) /* differential */ | |
2991a1ca | 173 | #define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */ |
ffa458c1 DB |
174 | #define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ |
175 | #define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ | |
176 | #define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ | |
177 | ||
178 | #define MAX_12BIT ((1<<12)-1) | |
179 | ||
180 | /* leave ADC powered up (disables penirq) between differential samples */ | |
de2defd9 ID |
181 | #define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ |
182 | | ADS_12_BIT | ADS_DFR | \ | |
183 | (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) | |
ffa458c1 | 184 | |
de2defd9 ID |
185 | #define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) |
186 | #define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) | |
187 | #define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) | |
53a0ef89 | 188 | |
de2defd9 ID |
189 | #define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) |
190 | #define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ | |
ffa458c1 DB |
191 | |
192 | /* single-ended samples need to first power up reference voltage; | |
193 | * we leave both ADC and VREF powered | |
194 | */ | |
195 | #define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ | |
196 | | ADS_12_BIT | ADS_SER) | |
197 | ||
de2defd9 ID |
198 | #define REF_ON (READ_12BIT_DFR(x, 1, 1)) |
199 | #define REF_OFF (READ_12BIT_DFR(y, 0, 0)) | |
ffa458c1 | 200 | |
2991a1ca JW |
201 | /* Must be called with ts->lock held */ |
202 | static void ads7846_stop(struct ads7846 *ts) | |
203 | { | |
204 | if (!ts->disabled && !ts->suspended) { | |
205 | /* Signal IRQ thread to stop polling and disable the handler. */ | |
206 | ts->stopped = true; | |
207 | mb(); | |
208 | wake_up(&ts->wait); | |
209 | disable_irq(ts->spi->irq); | |
210 | } | |
211 | } | |
212 | ||
213 | /* Must be called with ts->lock held */ | |
214 | static void ads7846_restart(struct ads7846 *ts) | |
215 | { | |
216 | if (!ts->disabled && !ts->suspended) { | |
217 | /* Tell IRQ thread that it may poll the device. */ | |
218 | ts->stopped = false; | |
219 | mb(); | |
220 | enable_irq(ts->spi->irq); | |
221 | } | |
222 | } | |
223 | ||
224 | /* Must be called with ts->lock held */ | |
225 | static void __ads7846_disable(struct ads7846 *ts) | |
226 | { | |
227 | ads7846_stop(ts); | |
228 | regulator_disable(ts->reg); | |
229 | ||
230 | /* | |
231 | * We know the chip's in low power mode since we always | |
232 | * leave it that way after every request | |
233 | */ | |
234 | } | |
235 | ||
236 | /* Must be called with ts->lock held */ | |
237 | static void __ads7846_enable(struct ads7846 *ts) | |
238 | { | |
f94352f8 MB |
239 | int error; |
240 | ||
241 | error = regulator_enable(ts->reg); | |
242 | if (error != 0) | |
243 | dev_err(&ts->spi->dev, "Failed to enable supply: %d\n", error); | |
244 | ||
2991a1ca JW |
245 | ads7846_restart(ts); |
246 | } | |
247 | ||
248 | static void ads7846_disable(struct ads7846 *ts) | |
249 | { | |
250 | mutex_lock(&ts->lock); | |
251 | ||
252 | if (!ts->disabled) { | |
253 | ||
254 | if (!ts->suspended) | |
255 | __ads7846_disable(ts); | |
256 | ||
257 | ts->disabled = true; | |
258 | } | |
259 | ||
260 | mutex_unlock(&ts->lock); | |
261 | } | |
262 | ||
263 | static void ads7846_enable(struct ads7846 *ts) | |
264 | { | |
265 | mutex_lock(&ts->lock); | |
266 | ||
267 | if (ts->disabled) { | |
268 | ||
269 | ts->disabled = false; | |
270 | ||
271 | if (!ts->suspended) | |
272 | __ads7846_enable(ts); | |
273 | } | |
274 | ||
275 | mutex_unlock(&ts->lock); | |
276 | } | |
277 | ||
ffa458c1 DB |
278 | /*--------------------------------------------------------------------------*/ |
279 | ||
280 | /* | |
281 | * Non-touchscreen sensors only use single-ended conversions. | |
2c8dc071 DB |
282 | * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; |
283 | * ads7846 lets that pin be unconnected, to use internal vREF. | |
ffa458c1 DB |
284 | */ |
285 | ||
286 | struct ser_req { | |
d93f70b2 | 287 | u8 ref_on; |
ffa458c1 | 288 | u8 command; |
d93f70b2 | 289 | u8 ref_off; |
ffa458c1 | 290 | u16 scratch; |
ffa458c1 DB |
291 | struct spi_message msg; |
292 | struct spi_transfer xfer[6]; | |
1dbe7dad AS |
293 | /* |
294 | * DMA (thus cache coherency maintenance) requires the | |
295 | * transfer buffers to live in their own cache lines. | |
296 | */ | |
297 | __be16 sample ____cacheline_aligned; | |
ffa458c1 DB |
298 | }; |
299 | ||
3eac5c7e AG |
300 | struct ads7845_ser_req { |
301 | u8 command[3]; | |
3eac5c7e AG |
302 | struct spi_message msg; |
303 | struct spi_transfer xfer[2]; | |
1dbe7dad AS |
304 | /* |
305 | * DMA (thus cache coherency maintenance) requires the | |
306 | * transfer buffers to live in their own cache lines. | |
307 | */ | |
308 | u8 sample[3] ____cacheline_aligned; | |
3eac5c7e AG |
309 | }; |
310 | ||
ffa458c1 DB |
311 | static int ads7846_read12_ser(struct device *dev, unsigned command) |
312 | { | |
2991a1ca JW |
313 | struct spi_device *spi = to_spi_device(dev); |
314 | struct ads7846 *ts = dev_get_drvdata(dev); | |
315 | struct ser_req *req; | |
316 | int status; | |
ffa458c1 | 317 | |
2991a1ca | 318 | req = kzalloc(sizeof *req, GFP_KERNEL); |
ffa458c1 DB |
319 | if (!req) |
320 | return -ENOMEM; | |
321 | ||
0b7018aa | 322 | spi_message_init(&req->msg); |
8275c642 | 323 | |
2c8dc071 | 324 | /* maybe turn on internal vREF, and let it settle */ |
ebcaaad9 | 325 | if (ts->use_internal) { |
2c8dc071 DB |
326 | req->ref_on = REF_ON; |
327 | req->xfer[0].tx_buf = &req->ref_on; | |
328 | req->xfer[0].len = 1; | |
329 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
330 | ||
331 | req->xfer[1].rx_buf = &req->scratch; | |
332 | req->xfer[1].len = 2; | |
333 | ||
334 | /* for 1uF, settle for 800 usec; no cap, 100 usec. */ | |
335 | req->xfer[1].delay_usecs = ts->vref_delay_usecs; | |
336 | spi_message_add_tail(&req->xfer[1], &req->msg); | |
ebcaaad9 AS |
337 | |
338 | /* Enable reference voltage */ | |
339 | command |= ADS_PD10_REF_ON; | |
2c8dc071 | 340 | } |
ffa458c1 | 341 | |
ebcaaad9 AS |
342 | /* Enable ADC in every case */ |
343 | command |= ADS_PD10_ADC_ON; | |
344 | ||
ffa458c1 DB |
345 | /* take sample */ |
346 | req->command = (u8) command; | |
347 | req->xfer[2].tx_buf = &req->command; | |
348 | req->xfer[2].len = 1; | |
2c8dc071 DB |
349 | spi_message_add_tail(&req->xfer[2], &req->msg); |
350 | ||
ffa458c1 DB |
351 | req->xfer[3].rx_buf = &req->sample; |
352 | req->xfer[3].len = 2; | |
2c8dc071 | 353 | spi_message_add_tail(&req->xfer[3], &req->msg); |
ffa458c1 DB |
354 | |
355 | /* REVISIT: take a few more samples, and compare ... */ | |
356 | ||
969111e9 NF |
357 | /* converter in low power mode & enable PENIRQ */ |
358 | req->ref_off = PWRDOWN; | |
359 | req->xfer[4].tx_buf = &req->ref_off; | |
360 | req->xfer[4].len = 1; | |
361 | spi_message_add_tail(&req->xfer[4], &req->msg); | |
362 | ||
363 | req->xfer[5].rx_buf = &req->scratch; | |
364 | req->xfer[5].len = 2; | |
365 | CS_CHANGE(req->xfer[5]); | |
366 | spi_message_add_tail(&req->xfer[5], &req->msg); | |
ffa458c1 | 367 | |
2991a1ca JW |
368 | mutex_lock(&ts->lock); |
369 | ads7846_stop(ts); | |
ffa458c1 | 370 | status = spi_sync(spi, &req->msg); |
2991a1ca JW |
371 | ads7846_restart(ts); |
372 | mutex_unlock(&ts->lock); | |
ffa458c1 | 373 | |
c24b2602 MP |
374 | if (status == 0) { |
375 | /* on-wire is a must-ignore bit, a BE12 value, then padding */ | |
7c6d0ee1 DB |
376 | status = be16_to_cpu(req->sample); |
377 | status = status >> 3; | |
378 | status &= 0x0fff; | |
c24b2602 | 379 | } |
ffa458c1 | 380 | |
9084533e | 381 | kfree(req); |
7c6d0ee1 | 382 | return status; |
ffa458c1 DB |
383 | } |
384 | ||
3eac5c7e AG |
385 | static int ads7845_read12_ser(struct device *dev, unsigned command) |
386 | { | |
2991a1ca JW |
387 | struct spi_device *spi = to_spi_device(dev); |
388 | struct ads7846 *ts = dev_get_drvdata(dev); | |
389 | struct ads7845_ser_req *req; | |
390 | int status; | |
3eac5c7e | 391 | |
2991a1ca | 392 | req = kzalloc(sizeof *req, GFP_KERNEL); |
3eac5c7e AG |
393 | if (!req) |
394 | return -ENOMEM; | |
395 | ||
396 | spi_message_init(&req->msg); | |
397 | ||
398 | req->command[0] = (u8) command; | |
399 | req->xfer[0].tx_buf = req->command; | |
400 | req->xfer[0].rx_buf = req->sample; | |
401 | req->xfer[0].len = 3; | |
402 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
403 | ||
2991a1ca JW |
404 | mutex_lock(&ts->lock); |
405 | ads7846_stop(ts); | |
3eac5c7e | 406 | status = spi_sync(spi, &req->msg); |
2991a1ca JW |
407 | ads7846_restart(ts); |
408 | mutex_unlock(&ts->lock); | |
3eac5c7e AG |
409 | |
410 | if (status == 0) { | |
411 | /* BE12 value, then padding */ | |
412 | status = be16_to_cpu(*((u16 *)&req->sample[1])); | |
413 | status = status >> 3; | |
414 | status &= 0x0fff; | |
415 | } | |
416 | ||
417 | kfree(req); | |
418 | return status; | |
419 | } | |
420 | ||
2c8dc071 DB |
421 | #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) |
422 | ||
423 | #define SHOW(name, var, adjust) static ssize_t \ | |
ffa458c1 DB |
424 | name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ |
425 | { \ | |
2c8dc071 | 426 | struct ads7846 *ts = dev_get_drvdata(dev); \ |
ffa458c1 | 427 | ssize_t v = ads7846_read12_ser(dev, \ |
ebcaaad9 | 428 | READ_12BIT_SER(var)); \ |
ffa458c1 DB |
429 | if (v < 0) \ |
430 | return v; \ | |
2c8dc071 | 431 | return sprintf(buf, "%u\n", adjust(ts, v)); \ |
ffa458c1 DB |
432 | } \ |
433 | static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); | |
434 | ||
2c8dc071 | 435 | |
b731d7b6 | 436 | /* Sysfs conventions report temperatures in millidegrees Celsius. |
2c8dc071 DB |
437 | * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high |
438 | * accuracy scheme without calibration data. For now we won't try either; | |
439 | * userspace sees raw sensor values, and must scale/calibrate appropriately. | |
440 | */ | |
441 | static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) | |
442 | { | |
443 | return v; | |
444 | } | |
445 | ||
446 | SHOW(temp0, temp0, null_adjust) /* temp1_input */ | |
447 | SHOW(temp1, temp1, null_adjust) /* temp2_input */ | |
448 | ||
449 | ||
450 | /* sysfs conventions report voltages in millivolts. We can convert voltages | |
451 | * if we know vREF. userspace may need to scale vAUX to match the board's | |
452 | * external resistors; we assume that vBATT only uses the internal ones. | |
453 | */ | |
454 | static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) | |
455 | { | |
456 | unsigned retval = v; | |
457 | ||
458 | /* external resistors may scale vAUX into 0..vREF */ | |
7c6d0ee1 | 459 | retval *= ts->vref_mv; |
2c8dc071 | 460 | retval = retval >> 12; |
2991a1ca | 461 | |
2c8dc071 DB |
462 | return retval; |
463 | } | |
464 | ||
465 | static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) | |
466 | { | |
467 | unsigned retval = vaux_adjust(ts, v); | |
468 | ||
469 | /* ads7846 has a resistor ladder to scale this signal down */ | |
470 | if (ts->model == 7846) | |
471 | retval *= 4; | |
2991a1ca | 472 | |
2c8dc071 DB |
473 | return retval; |
474 | } | |
475 | ||
476 | SHOW(in0_input, vaux, vaux_adjust) | |
477 | SHOW(in1_input, vbatt, vbatt_adjust) | |
478 | ||
2c8dc071 DB |
479 | static struct attribute *ads7846_attributes[] = { |
480 | &dev_attr_temp0.attr, | |
481 | &dev_attr_temp1.attr, | |
482 | &dev_attr_in0_input.attr, | |
483 | &dev_attr_in1_input.attr, | |
484 | NULL, | |
485 | }; | |
486 | ||
487 | static struct attribute_group ads7846_attr_group = { | |
488 | .attrs = ads7846_attributes, | |
489 | }; | |
490 | ||
491 | static struct attribute *ads7843_attributes[] = { | |
492 | &dev_attr_in0_input.attr, | |
493 | &dev_attr_in1_input.attr, | |
494 | NULL, | |
495 | }; | |
496 | ||
497 | static struct attribute_group ads7843_attr_group = { | |
498 | .attrs = ads7843_attributes, | |
499 | }; | |
500 | ||
501 | static struct attribute *ads7845_attributes[] = { | |
502 | &dev_attr_in0_input.attr, | |
503 | NULL, | |
504 | }; | |
505 | ||
506 | static struct attribute_group ads7845_attr_group = { | |
507 | .attrs = ads7845_attributes, | |
508 | }; | |
509 | ||
510 | static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) | |
511 | { | |
1beeffe4 | 512 | struct device *hwmon; |
2c8dc071 DB |
513 | int err; |
514 | ||
515 | /* hwmon sensors need a reference voltage */ | |
516 | switch (ts->model) { | |
517 | case 7846: | |
7c6d0ee1 | 518 | if (!ts->vref_mv) { |
2c8dc071 | 519 | dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); |
7c6d0ee1 | 520 | ts->vref_mv = 2500; |
ebcaaad9 | 521 | ts->use_internal = true; |
2c8dc071 DB |
522 | } |
523 | break; | |
524 | case 7845: | |
525 | case 7843: | |
7c6d0ee1 | 526 | if (!ts->vref_mv) { |
2c8dc071 DB |
527 | dev_warn(&spi->dev, |
528 | "external vREF for ADS%d not specified\n", | |
529 | ts->model); | |
530 | return 0; | |
531 | } | |
532 | break; | |
533 | } | |
534 | ||
535 | /* different chips have different sensor groups */ | |
536 | switch (ts->model) { | |
537 | case 7846: | |
538 | ts->attr_group = &ads7846_attr_group; | |
539 | break; | |
540 | case 7845: | |
541 | ts->attr_group = &ads7845_attr_group; | |
542 | break; | |
543 | case 7843: | |
544 | ts->attr_group = &ads7843_attr_group; | |
545 | break; | |
546 | default: | |
547 | dev_dbg(&spi->dev, "ADS%d not recognized\n", ts->model); | |
548 | return 0; | |
549 | } | |
550 | ||
551 | err = sysfs_create_group(&spi->dev.kobj, ts->attr_group); | |
552 | if (err) | |
553 | return err; | |
554 | ||
555 | hwmon = hwmon_device_register(&spi->dev); | |
556 | if (IS_ERR(hwmon)) { | |
557 | sysfs_remove_group(&spi->dev.kobj, ts->attr_group); | |
558 | return PTR_ERR(hwmon); | |
559 | } | |
560 | ||
561 | ts->hwmon = hwmon; | |
562 | return 0; | |
563 | } | |
564 | ||
565 | static void ads784x_hwmon_unregister(struct spi_device *spi, | |
566 | struct ads7846 *ts) | |
567 | { | |
568 | if (ts->hwmon) { | |
569 | sysfs_remove_group(&spi->dev.kobj, ts->attr_group); | |
570 | hwmon_device_unregister(ts->hwmon); | |
571 | } | |
572 | } | |
573 | ||
574 | #else | |
575 | static inline int ads784x_hwmon_register(struct spi_device *spi, | |
576 | struct ads7846 *ts) | |
577 | { | |
578 | return 0; | |
579 | } | |
580 | ||
581 | static inline void ads784x_hwmon_unregister(struct spi_device *spi, | |
582 | struct ads7846 *ts) | |
583 | { | |
584 | } | |
585 | #endif | |
ffa458c1 | 586 | |
438f2a74 ID |
587 | static ssize_t ads7846_pen_down_show(struct device *dev, |
588 | struct device_attribute *attr, char *buf) | |
589 | { | |
2991a1ca JW |
590 | struct ads7846 *ts = dev_get_drvdata(dev); |
591 | ||
592 | return sprintf(buf, "%u\n", ts->pendown); | |
438f2a74 ID |
593 | } |
594 | ||
595 | static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); | |
596 | ||
7de90a8c ID |
597 | static ssize_t ads7846_disable_show(struct device *dev, |
598 | struct device_attribute *attr, char *buf) | |
599 | { | |
2991a1ca | 600 | struct ads7846 *ts = dev_get_drvdata(dev); |
7de90a8c ID |
601 | |
602 | return sprintf(buf, "%u\n", ts->disabled); | |
603 | } | |
604 | ||
605 | static ssize_t ads7846_disable_store(struct device *dev, | |
606 | struct device_attribute *attr, | |
607 | const char *buf, size_t count) | |
608 | { | |
609 | struct ads7846 *ts = dev_get_drvdata(dev); | |
76496e7a JD |
610 | unsigned int i; |
611 | int err; | |
160f1fef | 612 | |
76496e7a JD |
613 | err = kstrtouint(buf, 10, &i); |
614 | if (err) | |
615 | return err; | |
7de90a8c | 616 | |
7de90a8c ID |
617 | if (i) |
618 | ads7846_disable(ts); | |
619 | else | |
620 | ads7846_enable(ts); | |
621 | ||
7de90a8c ID |
622 | return count; |
623 | } | |
624 | ||
625 | static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); | |
626 | ||
2c8dc071 | 627 | static struct attribute *ads784x_attributes[] = { |
8dd51650 DT |
628 | &dev_attr_pen_down.attr, |
629 | &dev_attr_disable.attr, | |
630 | NULL, | |
631 | }; | |
632 | ||
2c8dc071 DB |
633 | static struct attribute_group ads784x_attr_group = { |
634 | .attrs = ads784x_attributes, | |
8dd51650 DT |
635 | }; |
636 | ||
ffa458c1 DB |
637 | /*--------------------------------------------------------------------------*/ |
638 | ||
4d5975e5 EM |
639 | static int get_pendown_state(struct ads7846 *ts) |
640 | { | |
641 | if (ts->get_pendown_state) | |
642 | return ts->get_pendown_state(); | |
643 | ||
644 | return !gpio_get_value(ts->gpio_pendown); | |
645 | } | |
646 | ||
fd746d54 EM |
647 | static void null_wait_for_sync(void) |
648 | { | |
649 | } | |
650 | ||
2991a1ca JW |
651 | static int ads7846_debounce_filter(void *ads, int data_idx, int *val) |
652 | { | |
653 | struct ads7846 *ts = ads; | |
654 | ||
655 | if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { | |
656 | /* Start over collecting consistent readings. */ | |
657 | ts->read_rep = 0; | |
658 | /* | |
659 | * Repeat it, if this was the first read or the read | |
660 | * wasn't consistent enough. | |
661 | */ | |
662 | if (ts->read_cnt < ts->debounce_max) { | |
663 | ts->last_read = *val; | |
664 | ts->read_cnt++; | |
665 | return ADS7846_FILTER_REPEAT; | |
666 | } else { | |
667 | /* | |
668 | * Maximum number of debouncing reached and still | |
669 | * not enough number of consistent readings. Abort | |
670 | * the whole sample, repeat it in the next sampling | |
671 | * period. | |
672 | */ | |
673 | ts->read_cnt = 0; | |
674 | return ADS7846_FILTER_IGNORE; | |
675 | } | |
676 | } else { | |
677 | if (++ts->read_rep > ts->debounce_rep) { | |
678 | /* | |
679 | * Got a good reading for this coordinate, | |
680 | * go for the next one. | |
681 | */ | |
682 | ts->read_cnt = 0; | |
683 | ts->read_rep = 0; | |
684 | return ADS7846_FILTER_OK; | |
685 | } else { | |
686 | /* Read more values that are consistent. */ | |
687 | ts->read_cnt++; | |
688 | return ADS7846_FILTER_REPEAT; | |
689 | } | |
690 | } | |
691 | } | |
692 | ||
693 | static int ads7846_no_filter(void *ads, int data_idx, int *val) | |
694 | { | |
695 | return ADS7846_FILTER_OK; | |
696 | } | |
697 | ||
698 | static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m) | |
699 | { | |
700 | struct spi_transfer *t = | |
701 | list_entry(m->transfers.prev, struct spi_transfer, transfer_list); | |
702 | ||
703 | if (ts->model == 7845) { | |
704 | return be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3; | |
705 | } else { | |
706 | /* | |
707 | * adjust: on-wire is a must-ignore bit, a BE12 value, then | |
708 | * padding; built from two 8 bit values written msb-first. | |
709 | */ | |
710 | return be16_to_cpup((__be16 *)t->rx_buf) >> 3; | |
711 | } | |
712 | } | |
713 | ||
714 | static void ads7846_update_value(struct spi_message *m, int val) | |
715 | { | |
716 | struct spi_transfer *t = | |
717 | list_entry(m->transfers.prev, struct spi_transfer, transfer_list); | |
718 | ||
719 | *(u16 *)t->rx_buf = val; | |
720 | } | |
721 | ||
722 | static void ads7846_read_state(struct ads7846 *ts) | |
723 | { | |
724 | struct ads7846_packet *packet = ts->packet; | |
725 | struct spi_message *m; | |
726 | int msg_idx = 0; | |
727 | int val; | |
728 | int action; | |
729 | int error; | |
730 | ||
731 | while (msg_idx < ts->msg_count) { | |
732 | ||
733 | ts->wait_for_sync(); | |
734 | ||
735 | m = &ts->msg[msg_idx]; | |
736 | error = spi_sync(ts->spi, m); | |
737 | if (error) { | |
738 | dev_err(&ts->spi->dev, "spi_async --> %d\n", error); | |
739 | packet->tc.ignore = true; | |
740 | return; | |
741 | } | |
742 | ||
743 | /* | |
744 | * Last message is power down request, no need to convert | |
745 | * or filter the value. | |
746 | */ | |
747 | if (msg_idx < ts->msg_count - 1) { | |
ffa458c1 | 748 | |
2991a1ca JW |
749 | val = ads7846_get_value(ts, m); |
750 | ||
751 | action = ts->filter(ts->filter_data, msg_idx, &val); | |
752 | switch (action) { | |
753 | case ADS7846_FILTER_REPEAT: | |
754 | continue; | |
755 | ||
756 | case ADS7846_FILTER_IGNORE: | |
757 | packet->tc.ignore = true; | |
758 | msg_idx = ts->msg_count - 1; | |
759 | continue; | |
760 | ||
761 | case ADS7846_FILTER_OK: | |
762 | ads7846_update_value(m, val); | |
763 | packet->tc.ignore = false; | |
764 | msg_idx++; | |
765 | break; | |
766 | ||
767 | default: | |
768 | BUG(); | |
769 | } | |
770 | } else { | |
771 | msg_idx++; | |
772 | } | |
773 | } | |
774 | } | |
775 | ||
776 | static void ads7846_report_state(struct ads7846 *ts) | |
ffa458c1 | 777 | { |
2991a1ca JW |
778 | struct ads7846_packet *packet = ts->packet; |
779 | unsigned int Rt; | |
780 | u16 x, y, z1, z2; | |
ffa458c1 | 781 | |
2991a1ca JW |
782 | /* |
783 | * ads7846_get_value() does in-place conversion (including byte swap) | |
784 | * from on-the-wire format as part of debouncing to get stable | |
785 | * readings. | |
ffa458c1 | 786 | */ |
3eac5c7e AG |
787 | if (ts->model == 7845) { |
788 | x = *(u16 *)packet->tc.x_buf; | |
789 | y = *(u16 *)packet->tc.y_buf; | |
790 | z1 = 0; | |
791 | z2 = 0; | |
792 | } else { | |
793 | x = packet->tc.x; | |
794 | y = packet->tc.y; | |
795 | z1 = packet->tc.z1; | |
796 | z2 = packet->tc.z2; | |
797 | } | |
ffa458c1 DB |
798 | |
799 | /* range filtering */ | |
800 | if (x == MAX_12BIT) | |
801 | x = 0; | |
802 | ||
9460b652 HCE |
803 | if (ts->model == 7843) { |
804 | Rt = ts->pressure_max / 2; | |
3eac5c7e AG |
805 | } else if (ts->model == 7845) { |
806 | if (get_pendown_state(ts)) | |
807 | Rt = ts->pressure_max / 2; | |
808 | else | |
809 | Rt = 0; | |
810 | dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt); | |
9460b652 | 811 | } else if (likely(x && z1)) { |
ffa458c1 DB |
812 | /* compute touch pressure resistance using equation #2 */ |
813 | Rt = z2; | |
814 | Rt -= z1; | |
815 | Rt *= x; | |
816 | Rt *= ts->x_plate_ohms; | |
817 | Rt /= z1; | |
818 | Rt = (Rt + 2047) >> 12; | |
9460b652 | 819 | } else { |
ffa458c1 | 820 | Rt = 0; |
9460b652 | 821 | } |
969111e9 | 822 | |
2991a1ca JW |
823 | /* |
824 | * Sample found inconsistent by debouncing or pressure is beyond | |
1936d590 ID |
825 | * the maximum. Don't report it to user space, repeat at least |
826 | * once more the measurement | |
827 | */ | |
e8f462d2 | 828 | if (packet->tc.ignore || Rt > ts->pressure_max) { |
52ce4eaa PM |
829 | dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", |
830 | packet->tc.ignore, Rt); | |
d5b415c9 ID |
831 | return; |
832 | } | |
833 | ||
2991a1ca JW |
834 | /* |
835 | * Maybe check the pendown state before reporting. This discards | |
1d25891f SH |
836 | * false readings when the pen is lifted. |
837 | */ | |
838 | if (ts->penirq_recheck_delay_usecs) { | |
839 | udelay(ts->penirq_recheck_delay_usecs); | |
4d5975e5 | 840 | if (!get_pendown_state(ts)) |
1d25891f SH |
841 | Rt = 0; |
842 | } | |
843 | ||
2991a1ca JW |
844 | /* |
845 | * NOTE: We can't rely on the pressure to determine the pen down | |
846 | * state, even this controller has a pressure sensor. The pressure | |
15e3589e ID |
847 | * value can fluctuate for quite a while after lifting the pen and |
848 | * in some cases may not even settle at the expected value. | |
ffa458c1 | 849 | * |
15e3589e ID |
850 | * The only safe way to check for the pen up condition is in the |
851 | * timer by reading the pen signal state (it's a GPIO _and_ IRQ). | |
ffa458c1 | 852 | */ |
ffa458c1 | 853 | if (Rt) { |
15e3589e | 854 | struct input_dev *input = ts->input; |
ae82d5ab | 855 | |
2991a1ca JW |
856 | if (ts->swap_xy) |
857 | swap(x, y); | |
858 | ||
15e3589e ID |
859 | if (!ts->pendown) { |
860 | input_report_key(input, BTN_TOUCH, 1); | |
2991a1ca | 861 | ts->pendown = true; |
52ce4eaa | 862 | dev_vdbg(&ts->spi->dev, "DOWN\n"); |
15e3589e | 863 | } |
86579a4c | 864 | |
15e3589e ID |
865 | input_report_abs(input, ABS_X, x); |
866 | input_report_abs(input, ABS_Y, y); | |
30ad7ba0 | 867 | input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); |
ffa458c1 | 868 | |
15e3589e | 869 | input_sync(input); |
52ce4eaa | 870 | dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); |
15e3589e | 871 | } |
da970e69 ID |
872 | } |
873 | ||
2991a1ca | 874 | static irqreturn_t ads7846_hard_irq(int irq, void *handle) |
da970e69 | 875 | { |
2991a1ca | 876 | struct ads7846 *ts = handle; |
da970e69 | 877 | |
2991a1ca | 878 | return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; |
0b7018aa ID |
879 | } |
880 | ||
0b7018aa | 881 | |
7d12e780 | 882 | static irqreturn_t ads7846_irq(int irq, void *handle) |
0b7018aa ID |
883 | { |
884 | struct ads7846 *ts = handle; | |
7de90a8c | 885 | |
2991a1ca JW |
886 | /* Start with a small delay before checking pendown state */ |
887 | msleep(TS_POLL_DELAY); | |
ffa458c1 | 888 | |
2991a1ca | 889 | while (!ts->stopped && get_pendown_state(ts)) { |
ffa458c1 | 890 | |
2991a1ca JW |
891 | /* pen is down, continue with the measurement */ |
892 | ads7846_read_state(ts); | |
ffa458c1 | 893 | |
2991a1ca JW |
894 | if (!ts->stopped) |
895 | ads7846_report_state(ts); | |
c9e617a5 | 896 | |
2991a1ca JW |
897 | wait_event_timeout(ts->wait, ts->stopped, |
898 | msecs_to_jiffies(TS_POLL_PERIOD)); | |
ffa458c1 DB |
899 | } |
900 | ||
2991a1ca JW |
901 | if (ts->pendown) { |
902 | struct input_dev *input = ts->input; | |
7de90a8c | 903 | |
2991a1ca JW |
904 | input_report_key(input, BTN_TOUCH, 0); |
905 | input_report_abs(input, ABS_PRESSURE, 0); | |
906 | input_sync(input); | |
7de90a8c | 907 | |
2991a1ca JW |
908 | ts->pendown = false; |
909 | dev_vdbg(&ts->spi->dev, "UP\n"); | |
910 | } | |
91143379 | 911 | |
2991a1ca | 912 | return IRQ_HANDLED; |
7de90a8c ID |
913 | } |
914 | ||
3c36e719 MB |
915 | #ifdef CONFIG_PM_SLEEP |
916 | static int ads7846_suspend(struct device *dev) | |
7de90a8c | 917 | { |
3c36e719 | 918 | struct ads7846 *ts = dev_get_drvdata(dev); |
7de90a8c | 919 | |
2991a1ca | 920 | mutex_lock(&ts->lock); |
7de90a8c | 921 | |
2991a1ca | 922 | if (!ts->suspended) { |
7de90a8c | 923 | |
2991a1ca JW |
924 | if (!ts->disabled) |
925 | __ads7846_disable(ts); | |
7de90a8c | 926 | |
2991a1ca JW |
927 | if (device_may_wakeup(&ts->spi->dev)) |
928 | enable_irq_wake(ts->spi->irq); | |
fdba2bb1 | 929 | |
2991a1ca JW |
930 | ts->suspended = true; |
931 | } | |
932 | ||
933 | mutex_unlock(&ts->lock); | |
7de90a8c | 934 | |
2991a1ca | 935 | return 0; |
ffa458c1 DB |
936 | } |
937 | ||
3c36e719 | 938 | static int ads7846_resume(struct device *dev) |
ffa458c1 | 939 | { |
3c36e719 | 940 | struct ads7846 *ts = dev_get_drvdata(dev); |
ffa458c1 | 941 | |
2991a1ca JW |
942 | mutex_lock(&ts->lock); |
943 | ||
944 | if (ts->suspended) { | |
fdba2bb1 | 945 | |
2991a1ca | 946 | ts->suspended = false; |
7de90a8c | 947 | |
2991a1ca JW |
948 | if (device_may_wakeup(&ts->spi->dev)) |
949 | disable_irq_wake(ts->spi->irq); | |
7de90a8c | 950 | |
2991a1ca JW |
951 | if (!ts->disabled) |
952 | __ads7846_enable(ts); | |
953 | } | |
954 | ||
955 | mutex_unlock(&ts->lock); | |
7de90a8c | 956 | |
ffa458c1 DB |
957 | return 0; |
958 | } | |
3c36e719 MB |
959 | #endif |
960 | ||
961 | static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume); | |
ffa458c1 | 962 | |
5298cc4c | 963 | static int ads7846_setup_pendown(struct spi_device *spi, |
c4f49254 | 964 | struct ads7846 *ts) |
4d5975e5 EM |
965 | { |
966 | struct ads7846_platform_data *pdata = spi->dev.platform_data; | |
967 | int err; | |
968 | ||
0fbc9fdb DT |
969 | /* |
970 | * REVISIT when the irq can be triggered active-low, or if for some | |
4d5975e5 EM |
971 | * reason the touchscreen isn't hooked up, we don't need to access |
972 | * the pendown state. | |
973 | */ | |
4d5975e5 EM |
974 | |
975 | if (pdata->get_pendown_state) { | |
976 | ts->get_pendown_state = pdata->get_pendown_state; | |
0fbc9fdb | 977 | } else if (gpio_is_valid(pdata->gpio_pendown)) { |
4d5975e5 | 978 | |
58c24400 IG |
979 | err = gpio_request_one(pdata->gpio_pendown, GPIOF_IN, |
980 | "ads7846_pendown"); | |
0fbc9fdb | 981 | if (err) { |
58c24400 IG |
982 | dev_err(&spi->dev, |
983 | "failed to request/setup pendown GPIO%d: %d\n", | |
984 | pdata->gpio_pendown, err); | |
1201e7e6 IG |
985 | return err; |
986 | } | |
4d5975e5 | 987 | |
0fbc9fdb DT |
988 | ts->gpio_pendown = pdata->gpio_pendown; |
989 | ||
c4f49254 IG |
990 | if (pdata->gpio_pendown_debounce) |
991 | gpio_set_debounce(pdata->gpio_pendown, | |
992 | pdata->gpio_pendown_debounce); | |
0fbc9fdb DT |
993 | } else { |
994 | dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); | |
995 | return -EINVAL; | |
996 | } | |
2991a1ca | 997 | |
4d5975e5 EM |
998 | return 0; |
999 | } | |
1000 | ||
2991a1ca JW |
1001 | /* |
1002 | * Set up the transfers to read touchscreen state; this assumes we | |
1003 | * use formula #2 for pressure, not #3. | |
1004 | */ | |
5298cc4c | 1005 | static void ads7846_setup_spi_msg(struct ads7846 *ts, |
2991a1ca | 1006 | const struct ads7846_platform_data *pdata) |
ffa458c1 | 1007 | { |
2991a1ca JW |
1008 | struct spi_message *m = &ts->msg[0]; |
1009 | struct spi_transfer *x = ts->xfer; | |
1010 | struct ads7846_packet *packet = ts->packet; | |
1011 | int vref = pdata->keep_vref_on; | |
de2defd9 | 1012 | |
06a09124 | 1013 | if (ts->model == 7873) { |
2991a1ca JW |
1014 | /* |
1015 | * The AD7873 is almost identical to the ADS7846 | |
06a09124 | 1016 | * keep VREF off during differential/ratiometric |
2991a1ca | 1017 | * conversion modes. |
06a09124 MH |
1018 | */ |
1019 | ts->model = 7846; | |
1020 | vref = 0; | |
1021 | } | |
1022 | ||
2991a1ca | 1023 | ts->msg_count = 1; |
0b7018aa | 1024 | spi_message_init(m); |
2991a1ca | 1025 | m->context = ts; |
0b7018aa | 1026 | |
3eac5c7e AG |
1027 | if (ts->model == 7845) { |
1028 | packet->read_y_cmd[0] = READ_Y(vref); | |
1029 | packet->read_y_cmd[1] = 0; | |
1030 | packet->read_y_cmd[2] = 0; | |
1031 | x->tx_buf = &packet->read_y_cmd[0]; | |
1032 | x->rx_buf = &packet->tc.y_buf[0]; | |
1033 | x->len = 3; | |
1034 | spi_message_add_tail(x, m); | |
1035 | } else { | |
1036 | /* y- still on; turn on only y+ (and ADC) */ | |
1037 | packet->read_y = READ_Y(vref); | |
1038 | x->tx_buf = &packet->read_y; | |
1039 | x->len = 1; | |
1040 | spi_message_add_tail(x, m); | |
d93f70b2 | 1041 | |
3eac5c7e AG |
1042 | x++; |
1043 | x->rx_buf = &packet->tc.y; | |
1044 | x->len = 2; | |
1045 | spi_message_add_tail(x, m); | |
1046 | } | |
0b7018aa | 1047 | |
2991a1ca JW |
1048 | /* |
1049 | * The first sample after switching drivers can be low quality; | |
e4f48861 SH |
1050 | * optionally discard it, using a second one after the signals |
1051 | * have had enough time to stabilize. | |
1052 | */ | |
1053 | if (pdata->settle_delay_usecs) { | |
1054 | x->delay_usecs = pdata->settle_delay_usecs; | |
1055 | ||
1056 | x++; | |
e8f462d2 | 1057 | x->tx_buf = &packet->read_y; |
e4f48861 SH |
1058 | x->len = 1; |
1059 | spi_message_add_tail(x, m); | |
1060 | ||
1061 | x++; | |
e8f462d2 | 1062 | x->rx_buf = &packet->tc.y; |
e4f48861 SH |
1063 | x->len = 2; |
1064 | spi_message_add_tail(x, m); | |
1065 | } | |
1066 | ||
2991a1ca | 1067 | ts->msg_count++; |
0b7018aa ID |
1068 | m++; |
1069 | spi_message_init(m); | |
2991a1ca | 1070 | m->context = ts; |
0b7018aa | 1071 | |
3eac5c7e AG |
1072 | if (ts->model == 7845) { |
1073 | x++; | |
1074 | packet->read_x_cmd[0] = READ_X(vref); | |
1075 | packet->read_x_cmd[1] = 0; | |
1076 | packet->read_x_cmd[2] = 0; | |
1077 | x->tx_buf = &packet->read_x_cmd[0]; | |
1078 | x->rx_buf = &packet->tc.x_buf[0]; | |
1079 | x->len = 3; | |
1080 | spi_message_add_tail(x, m); | |
1081 | } else { | |
1082 | /* turn y- off, x+ on, then leave in lowpower */ | |
1083 | x++; | |
1084 | packet->read_x = READ_X(vref); | |
1085 | x->tx_buf = &packet->read_x; | |
1086 | x->len = 1; | |
1087 | spi_message_add_tail(x, m); | |
0b7018aa | 1088 | |
3eac5c7e AG |
1089 | x++; |
1090 | x->rx_buf = &packet->tc.x; | |
1091 | x->len = 2; | |
1092 | spi_message_add_tail(x, m); | |
1093 | } | |
0b7018aa | 1094 | |
e4f48861 SH |
1095 | /* ... maybe discard first sample ... */ |
1096 | if (pdata->settle_delay_usecs) { | |
1097 | x->delay_usecs = pdata->settle_delay_usecs; | |
1098 | ||
1099 | x++; | |
e8f462d2 | 1100 | x->tx_buf = &packet->read_x; |
e4f48861 SH |
1101 | x->len = 1; |
1102 | spi_message_add_tail(x, m); | |
1103 | ||
1104 | x++; | |
e8f462d2 | 1105 | x->rx_buf = &packet->tc.x; |
e4f48861 SH |
1106 | x->len = 2; |
1107 | spi_message_add_tail(x, m); | |
1108 | } | |
1109 | ||
ffa458c1 DB |
1110 | /* turn y+ off, x- on; we'll use formula #2 */ |
1111 | if (ts->model == 7846) { | |
2991a1ca | 1112 | ts->msg_count++; |
0b7018aa ID |
1113 | m++; |
1114 | spi_message_init(m); | |
2991a1ca | 1115 | m->context = ts; |
0b7018aa | 1116 | |
d93f70b2 | 1117 | x++; |
e8f462d2 DT |
1118 | packet->read_z1 = READ_Z1(vref); |
1119 | x->tx_buf = &packet->read_z1; | |
ffa458c1 | 1120 | x->len = 1; |
0b7018aa | 1121 | spi_message_add_tail(x, m); |
d93f70b2 | 1122 | |
ffa458c1 | 1123 | x++; |
e8f462d2 | 1124 | x->rx_buf = &packet->tc.z1; |
ffa458c1 | 1125 | x->len = 2; |
0b7018aa ID |
1126 | spi_message_add_tail(x, m); |
1127 | ||
e4f48861 SH |
1128 | /* ... maybe discard first sample ... */ |
1129 | if (pdata->settle_delay_usecs) { | |
1130 | x->delay_usecs = pdata->settle_delay_usecs; | |
1131 | ||
1132 | x++; | |
e8f462d2 | 1133 | x->tx_buf = &packet->read_z1; |
e4f48861 SH |
1134 | x->len = 1; |
1135 | spi_message_add_tail(x, m); | |
1136 | ||
1137 | x++; | |
e8f462d2 | 1138 | x->rx_buf = &packet->tc.z1; |
e4f48861 SH |
1139 | x->len = 2; |
1140 | spi_message_add_tail(x, m); | |
1141 | } | |
1142 | ||
2991a1ca | 1143 | ts->msg_count++; |
0b7018aa ID |
1144 | m++; |
1145 | spi_message_init(m); | |
2991a1ca | 1146 | m->context = ts; |
ffa458c1 | 1147 | |
d93f70b2 | 1148 | x++; |
e8f462d2 DT |
1149 | packet->read_z2 = READ_Z2(vref); |
1150 | x->tx_buf = &packet->read_z2; | |
ffa458c1 | 1151 | x->len = 1; |
0b7018aa | 1152 | spi_message_add_tail(x, m); |
d93f70b2 | 1153 | |
ffa458c1 | 1154 | x++; |
e8f462d2 | 1155 | x->rx_buf = &packet->tc.z2; |
ffa458c1 | 1156 | x->len = 2; |
0b7018aa | 1157 | spi_message_add_tail(x, m); |
ffa458c1 | 1158 | |
e4f48861 SH |
1159 | /* ... maybe discard first sample ... */ |
1160 | if (pdata->settle_delay_usecs) { | |
1161 | x->delay_usecs = pdata->settle_delay_usecs; | |
1162 | ||
1163 | x++; | |
e8f462d2 | 1164 | x->tx_buf = &packet->read_z2; |
e4f48861 SH |
1165 | x->len = 1; |
1166 | spi_message_add_tail(x, m); | |
1167 | ||
1168 | x++; | |
e8f462d2 | 1169 | x->rx_buf = &packet->tc.z2; |
e4f48861 SH |
1170 | x->len = 2; |
1171 | spi_message_add_tail(x, m); | |
1172 | } | |
0b7018aa | 1173 | } |
53a0ef89 ID |
1174 | |
1175 | /* power down */ | |
2991a1ca | 1176 | ts->msg_count++; |
0b7018aa ID |
1177 | m++; |
1178 | spi_message_init(m); | |
2991a1ca | 1179 | m->context = ts; |
0b7018aa | 1180 | |
3eac5c7e AG |
1181 | if (ts->model == 7845) { |
1182 | x++; | |
1183 | packet->pwrdown_cmd[0] = PWRDOWN; | |
1184 | packet->pwrdown_cmd[1] = 0; | |
1185 | packet->pwrdown_cmd[2] = 0; | |
1186 | x->tx_buf = &packet->pwrdown_cmd[0]; | |
1187 | x->len = 3; | |
1188 | } else { | |
1189 | x++; | |
1190 | packet->pwrdown = PWRDOWN; | |
1191 | x->tx_buf = &packet->pwrdown; | |
1192 | x->len = 1; | |
1193 | spi_message_add_tail(x, m); | |
1194 | ||
1195 | x++; | |
1196 | x->rx_buf = &packet->dummy; | |
1197 | x->len = 2; | |
1198 | } | |
53a0ef89 | 1199 | |
d93f70b2 | 1200 | CS_CHANGE(*x); |
0b7018aa | 1201 | spi_message_add_tail(x, m); |
2991a1ca | 1202 | } |
ffa458c1 | 1203 | |
5298cc4c | 1204 | static int ads7846_probe(struct spi_device *spi) |
2991a1ca JW |
1205 | { |
1206 | struct ads7846 *ts; | |
1207 | struct ads7846_packet *packet; | |
1208 | struct input_dev *input_dev; | |
1209 | struct ads7846_platform_data *pdata = spi->dev.platform_data; | |
1210 | unsigned long irq_flags; | |
1211 | int err; | |
1212 | ||
1213 | if (!spi->irq) { | |
1214 | dev_dbg(&spi->dev, "no IRQ?\n"); | |
1215 | return -ENODEV; | |
1216 | } | |
1217 | ||
1218 | if (!pdata) { | |
1219 | dev_dbg(&spi->dev, "no platform data?\n"); | |
1220 | return -ENODEV; | |
1221 | } | |
1222 | ||
1223 | /* don't exceed max specified sample rate */ | |
1224 | if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { | |
1225 | dev_dbg(&spi->dev, "f(sample) %d KHz?\n", | |
1226 | (spi->max_speed_hz/SAMPLE_BITS)/1000); | |
1227 | return -EINVAL; | |
1228 | } | |
1229 | ||
1230 | /* We'd set TX word size 8 bits and RX word size to 13 bits ... except | |
1231 | * that even if the hardware can do that, the SPI controller driver | |
1232 | * may not. So we stick to very-portable 8 bit words, both RX and TX. | |
1233 | */ | |
1234 | spi->bits_per_word = 8; | |
1235 | spi->mode = SPI_MODE_0; | |
1236 | err = spi_setup(spi); | |
1237 | if (err < 0) | |
1238 | return err; | |
ffa458c1 | 1239 | |
2991a1ca JW |
1240 | ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); |
1241 | packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); | |
1242 | input_dev = input_allocate_device(); | |
1243 | if (!ts || !packet || !input_dev) { | |
1244 | err = -ENOMEM; | |
1245 | goto err_free_mem; | |
1246 | } | |
1247 | ||
c12454fa | 1248 | spi_set_drvdata(spi, ts); |
2991a1ca JW |
1249 | |
1250 | ts->packet = packet; | |
1251 | ts->spi = spi; | |
1252 | ts->input = input_dev; | |
1253 | ts->vref_mv = pdata->vref_mv; | |
1254 | ts->swap_xy = pdata->swap_xy; | |
1255 | ||
1256 | mutex_init(&ts->lock); | |
1257 | init_waitqueue_head(&ts->wait); | |
1258 | ||
1259 | ts->model = pdata->model ? : 7846; | |
1260 | ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; | |
1261 | ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; | |
1262 | ts->pressure_max = pdata->pressure_max ? : ~0; | |
1263 | ||
1264 | if (pdata->filter != NULL) { | |
1265 | if (pdata->filter_init != NULL) { | |
1266 | err = pdata->filter_init(pdata, &ts->filter_data); | |
1267 | if (err < 0) | |
1268 | goto err_free_mem; | |
1269 | } | |
1270 | ts->filter = pdata->filter; | |
1271 | ts->filter_cleanup = pdata->filter_cleanup; | |
1272 | } else if (pdata->debounce_max) { | |
1273 | ts->debounce_max = pdata->debounce_max; | |
1274 | if (ts->debounce_max < 2) | |
1275 | ts->debounce_max = 2; | |
1276 | ts->debounce_tol = pdata->debounce_tol; | |
1277 | ts->debounce_rep = pdata->debounce_rep; | |
1278 | ts->filter = ads7846_debounce_filter; | |
1279 | ts->filter_data = ts; | |
1280 | } else { | |
1281 | ts->filter = ads7846_no_filter; | |
1282 | } | |
1283 | ||
1284 | err = ads7846_setup_pendown(spi, ts); | |
1285 | if (err) | |
1286 | goto err_cleanup_filter; | |
1287 | ||
1288 | if (pdata->penirq_recheck_delay_usecs) | |
1289 | ts->penirq_recheck_delay_usecs = | |
1290 | pdata->penirq_recheck_delay_usecs; | |
1291 | ||
1292 | ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; | |
1293 | ||
1294 | snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); | |
1295 | snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); | |
1296 | ||
1297 | input_dev->name = ts->name; | |
1298 | input_dev->phys = ts->phys; | |
1299 | input_dev->dev.parent = &spi->dev; | |
1300 | ||
1301 | input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); | |
1302 | input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); | |
1303 | input_set_abs_params(input_dev, ABS_X, | |
1304 | pdata->x_min ? : 0, | |
1305 | pdata->x_max ? : MAX_12BIT, | |
1306 | 0, 0); | |
1307 | input_set_abs_params(input_dev, ABS_Y, | |
1308 | pdata->y_min ? : 0, | |
1309 | pdata->y_max ? : MAX_12BIT, | |
1310 | 0, 0); | |
1311 | input_set_abs_params(input_dev, ABS_PRESSURE, | |
1312 | pdata->pressure_min, pdata->pressure_max, 0, 0); | |
1313 | ||
1314 | ads7846_setup_spi_msg(ts, pdata); | |
d5b415c9 | 1315 | |
91143379 GI |
1316 | ts->reg = regulator_get(&spi->dev, "vcc"); |
1317 | if (IS_ERR(ts->reg)) { | |
067fb2f6 | 1318 | err = PTR_ERR(ts->reg); |
56960b36 | 1319 | dev_err(&spi->dev, "unable to get regulator: %d\n", err); |
91143379 GI |
1320 | goto err_free_gpio; |
1321 | } | |
1322 | ||
1323 | err = regulator_enable(ts->reg); | |
1324 | if (err) { | |
1325 | dev_err(&spi->dev, "unable to enable regulator: %d\n", err); | |
1326 | goto err_put_regulator; | |
1327 | } | |
1328 | ||
0f622bf4 | 1329 | irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; |
2991a1ca | 1330 | irq_flags |= IRQF_ONESHOT; |
7804302b | 1331 | |
2991a1ca JW |
1332 | err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, |
1333 | irq_flags, spi->dev.driver->name, ts); | |
0f622bf4 | 1334 | if (err && !pdata->irq_flags) { |
c57c0a2a MR |
1335 | dev_info(&spi->dev, |
1336 | "trying pin change workaround on irq %d\n", spi->irq); | |
2991a1ca JW |
1337 | irq_flags |= IRQF_TRIGGER_RISING; |
1338 | err = request_threaded_irq(spi->irq, | |
1339 | ads7846_hard_irq, ads7846_irq, | |
1340 | irq_flags, spi->dev.driver->name, ts); | |
0f622bf4 DT |
1341 | } |
1342 | ||
1343 | if (err) { | |
1344 | dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); | |
1345 | goto err_disable_regulator; | |
ffa458c1 | 1346 | } |
ffa458c1 | 1347 | |
2c8dc071 DB |
1348 | err = ads784x_hwmon_register(spi, ts); |
1349 | if (err) | |
1350 | goto err_free_irq; | |
1351 | ||
2e5a7bd9 | 1352 | dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); |
ffa458c1 | 1353 | |
2991a1ca JW |
1354 | /* |
1355 | * Take a first sample, leaving nPENIRQ active and vREF off; avoid | |
ffa458c1 DB |
1356 | * the touchscreen, in case it's not connected. |
1357 | */ | |
3eac5c7e AG |
1358 | if (ts->model == 7845) |
1359 | ads7845_read12_ser(&spi->dev, PWRDOWN); | |
1360 | else | |
ebcaaad9 | 1361 | (void) ads7846_read12_ser(&spi->dev, READ_12BIT_SER(vaux)); |
ffa458c1 | 1362 | |
2c8dc071 | 1363 | err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); |
8dd51650 | 1364 | if (err) |
2c8dc071 | 1365 | goto err_remove_hwmon; |
7de90a8c | 1366 | |
a90f7e98 DT |
1367 | err = input_register_device(input_dev); |
1368 | if (err) | |
8dd51650 | 1369 | goto err_remove_attr_group; |
a90f7e98 | 1370 | |
fdba2bb1 RL |
1371 | device_init_wakeup(&spi->dev, pdata->wakeup); |
1372 | ||
ffa458c1 | 1373 | return 0; |
a90f7e98 | 1374 | |
8dd51650 | 1375 | err_remove_attr_group: |
2c8dc071 DB |
1376 | sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
1377 | err_remove_hwmon: | |
1378 | ads784x_hwmon_unregister(spi, ts); | |
8dd51650 | 1379 | err_free_irq: |
a90f7e98 | 1380 | free_irq(spi->irq, ts); |
91143379 GI |
1381 | err_disable_regulator: |
1382 | regulator_disable(ts->reg); | |
1383 | err_put_regulator: | |
1384 | regulator_put(ts->reg); | |
4d5975e5 | 1385 | err_free_gpio: |
0fbc9fdb | 1386 | if (!ts->get_pendown_state) |
4d5975e5 | 1387 | gpio_free(ts->gpio_pendown); |
da970e69 ID |
1388 | err_cleanup_filter: |
1389 | if (ts->filter_cleanup) | |
1390 | ts->filter_cleanup(ts->filter_data); | |
a90f7e98 DT |
1391 | err_free_mem: |
1392 | input_free_device(input_dev); | |
e8f462d2 | 1393 | kfree(packet); |
a90f7e98 DT |
1394 | kfree(ts); |
1395 | return err; | |
ffa458c1 DB |
1396 | } |
1397 | ||
e2619cf7 | 1398 | static int ads7846_remove(struct spi_device *spi) |
ffa458c1 | 1399 | { |
c12454fa | 1400 | struct ads7846 *ts = spi_get_drvdata(spi); |
ffa458c1 | 1401 | |
fdba2bb1 RL |
1402 | device_init_wakeup(&spi->dev, false); |
1403 | ||
2c8dc071 | 1404 | sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
ffa458c1 | 1405 | |
2991a1ca | 1406 | ads7846_disable(ts); |
7de90a8c | 1407 | free_irq(ts->spi->irq, ts); |
2991a1ca JW |
1408 | |
1409 | input_unregister_device(ts->input); | |
1410 | ||
1411 | ads784x_hwmon_unregister(spi, ts); | |
7de90a8c | 1412 | |
91143379 GI |
1413 | regulator_disable(ts->reg); |
1414 | regulator_put(ts->reg); | |
1415 | ||
0fbc9fdb DT |
1416 | if (!ts->get_pendown_state) { |
1417 | /* | |
1418 | * If we are not using specialized pendown method we must | |
1419 | * have been relying on gpio we set up ourselves. | |
1420 | */ | |
4d5975e5 | 1421 | gpio_free(ts->gpio_pendown); |
0fbc9fdb | 1422 | } |
4d5975e5 | 1423 | |
da970e69 ID |
1424 | if (ts->filter_cleanup) |
1425 | ts->filter_cleanup(ts->filter_data); | |
1426 | ||
e8f462d2 | 1427 | kfree(ts->packet); |
ffa458c1 DB |
1428 | kfree(ts); |
1429 | ||
2e5a7bd9 | 1430 | dev_dbg(&spi->dev, "unregistered touchscreen\n"); |
2991a1ca | 1431 | |
ffa458c1 DB |
1432 | return 0; |
1433 | } | |
1434 | ||
2e5a7bd9 DB |
1435 | static struct spi_driver ads7846_driver = { |
1436 | .driver = { | |
1437 | .name = "ads7846", | |
2e5a7bd9 | 1438 | .owner = THIS_MODULE, |
3c36e719 | 1439 | .pm = &ads7846_pm, |
2e5a7bd9 | 1440 | }, |
ffa458c1 | 1441 | .probe = ads7846_probe, |
1cb0aa88 | 1442 | .remove = ads7846_remove, |
ffa458c1 DB |
1443 | }; |
1444 | ||
ca83922e | 1445 | module_spi_driver(ads7846_driver); |
ffa458c1 DB |
1446 | |
1447 | MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); | |
1448 | MODULE_LICENSE("GPL"); | |
e0626e38 | 1449 | MODULE_ALIAS("spi:ads7846"); |