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