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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> |
3ac8bf07 | 34 | #include <asm/irq.h> |
ffa458c1 | 35 | |
ffa458c1 | 36 | /* |
9084533e | 37 | * This code has been heavily tested on a Nokia 770, and lightly |
52ce4eaa | 38 | * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). |
bff0de5f | 39 | * TSC2046 is just newer ads7846 silicon. |
969111e9 NF |
40 | * Support for ads7843 tested on Atmel at91sam926x-EK. |
41 | * Support for ads7845 has only been stubbed in. | |
06a09124 | 42 | * Support for Analog Devices AD7873 and AD7843 tested. |
ffa458c1 | 43 | * |
7de90a8c ID |
44 | * IRQ handling needs a workaround because of a shortcoming in handling |
45 | * edge triggered IRQs on some platforms like the OMAP1/2. These | |
46 | * platforms don't handle the ARM lazy IRQ disabling properly, thus we | |
47 | * have to maintain our own SW IRQ disabled status. This should be | |
48 | * removed as soon as the affected platform's IRQ handling is fixed. | |
49 | * | |
52ce4eaa | 50 | * App note sbaa036 talks in more detail about accurate sampling... |
ffa458c1 DB |
51 | * that ought to help in situations like LCDs inducing noise (which |
52 | * can also be helped by using synch signals) and more generally. | |
7de90a8c ID |
53 | * This driver tries to utilize the measures described in the app |
54 | * note. The strength of filtering can be set in the board-* specific | |
55 | * files. | |
ffa458c1 DB |
56 | */ |
57 | ||
2991a1ca JW |
58 | #define TS_POLL_DELAY 1 /* ms delay before the first sample */ |
59 | #define TS_POLL_PERIOD 5 /* ms delay between samples */ | |
ffa458c1 | 60 | |
d93f70b2 DB |
61 | /* this driver doesn't aim at the peak continuous sample rate */ |
62 | #define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) | |
63 | ||
ffa458c1 | 64 | struct ts_event { |
2991a1ca JW |
65 | /* |
66 | * For portability, we can't read 12 bit values using SPI (which | |
67 | * would make the controller deliver them as native byte order u16 | |
d93f70b2 | 68 | * with msbs zeroed). Instead, we read them as two 8-bit values, |
da970e69 | 69 | * *** WHICH NEED BYTESWAPPING *** and range adjustment. |
ffa458c1 | 70 | */ |
da970e69 ID |
71 | u16 x; |
72 | u16 y; | |
73 | u16 z1, z2; | |
2991a1ca | 74 | bool ignore; |
3eac5c7e AG |
75 | u8 x_buf[3]; |
76 | u8 y_buf[3]; | |
ffa458c1 DB |
77 | }; |
78 | ||
e8f462d2 DT |
79 | /* |
80 | * We allocate this separately to avoid cache line sharing issues when | |
81 | * driver is used with DMA-based SPI controllers (like atmel_spi) on | |
82 | * systems where main memory is not DMA-coherent (most non-x86 boards). | |
83 | */ | |
84 | struct ads7846_packet { | |
85 | u8 read_x, read_y, read_z1, read_z2, pwrdown; | |
86 | u16 dummy; /* for the pwrdown read */ | |
87 | struct ts_event tc; | |
3eac5c7e AG |
88 | /* for ads7845 with mpc5121 psc spi we use 3-byte buffers */ |
89 | u8 read_x_cmd[3], read_y_cmd[3], pwrdown_cmd[3]; | |
e8f462d2 DT |
90 | }; |
91 | ||
ffa458c1 | 92 | struct ads7846 { |
a90f7e98 | 93 | struct input_dev *input; |
ffa458c1 | 94 | char phys[32]; |
b58895f8 | 95 | char name[32]; |
ffa458c1 DB |
96 | |
97 | struct spi_device *spi; | |
91143379 | 98 | struct regulator *reg; |
2c8dc071 DB |
99 | |
100 | #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) | |
8dd51650 | 101 | struct attribute_group *attr_group; |
1beeffe4 | 102 | struct device *hwmon; |
2c8dc071 DB |
103 | #endif |
104 | ||
ffa458c1 | 105 | u16 model; |
7c6d0ee1 | 106 | u16 vref_mv; |
ffa458c1 DB |
107 | u16 vref_delay_usecs; |
108 | u16 x_plate_ohms; | |
d5b415c9 | 109 | u16 pressure_max; |
ffa458c1 | 110 | |
86579a4c MR |
111 | bool swap_xy; |
112 | ||
e8f462d2 | 113 | struct ads7846_packet *packet; |
ffa458c1 | 114 | |
e4f48861 | 115 | struct spi_transfer xfer[18]; |
0b7018aa | 116 | struct spi_message msg[5]; |
2991a1ca JW |
117 | int msg_count; |
118 | wait_queue_head_t wait; | |
119 | ||
120 | bool pendown; | |
121 | ||
0b7018aa | 122 | int read_cnt; |
d5b415c9 | 123 | int read_rep; |
0b7018aa ID |
124 | int last_read; |
125 | ||
126 | u16 debounce_max; | |
127 | u16 debounce_tol; | |
d5b415c9 | 128 | u16 debounce_rep; |
ffa458c1 | 129 | |
1d25891f SH |
130 | u16 penirq_recheck_delay_usecs; |
131 | ||
2991a1ca JW |
132 | struct mutex lock; |
133 | bool stopped; /* P: lock */ | |
134 | bool disabled; /* P: lock */ | |
135 | bool suspended; /* P: lock */ | |
c9e617a5 | 136 | |
da970e69 ID |
137 | int (*filter)(void *data, int data_idx, int *val); |
138 | void *filter_data; | |
139 | void (*filter_cleanup)(void *data); | |
c9e617a5 | 140 | int (*get_pendown_state)(void); |
4d5975e5 | 141 | int gpio_pendown; |
fd746d54 EM |
142 | |
143 | void (*wait_for_sync)(void); | |
ffa458c1 DB |
144 | }; |
145 | ||
146 | /* leave chip selected when we're done, for quicker re-select? */ | |
147 | #if 0 | |
148 | #define CS_CHANGE(xfer) ((xfer).cs_change = 1) | |
149 | #else | |
150 | #define CS_CHANGE(xfer) ((xfer).cs_change = 0) | |
151 | #endif | |
152 | ||
153 | /*--------------------------------------------------------------------------*/ | |
154 | ||
155 | /* The ADS7846 has touchscreen and other sensors. | |
156 | * Earlier ads784x chips are somewhat compatible. | |
157 | */ | |
158 | #define ADS_START (1 << 7) | |
159 | #define ADS_A2A1A0_d_y (1 << 4) /* differential */ | |
160 | #define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ | |
161 | #define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ | |
162 | #define ADS_A2A1A0_d_x (5 << 4) /* differential */ | |
163 | #define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ | |
164 | #define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ | |
165 | #define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ | |
166 | #define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ | |
167 | #define ADS_8_BIT (1 << 3) | |
168 | #define ADS_12_BIT (0 << 3) | |
169 | #define ADS_SER (1 << 2) /* non-differential */ | |
170 | #define ADS_DFR (0 << 2) /* differential */ | |
2991a1ca | 171 | #define ADS_PD10_PDOWN (0 << 0) /* low power mode + penirq */ |
ffa458c1 DB |
172 | #define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ |
173 | #define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ | |
174 | #define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ | |
175 | ||
176 | #define MAX_12BIT ((1<<12)-1) | |
177 | ||
178 | /* leave ADC powered up (disables penirq) between differential samples */ | |
de2defd9 ID |
179 | #define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ |
180 | | ADS_12_BIT | ADS_DFR | \ | |
181 | (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) | |
ffa458c1 | 182 | |
de2defd9 ID |
183 | #define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) |
184 | #define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) | |
185 | #define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) | |
53a0ef89 | 186 | |
de2defd9 ID |
187 | #define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) |
188 | #define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ | |
ffa458c1 DB |
189 | |
190 | /* single-ended samples need to first power up reference voltage; | |
191 | * we leave both ADC and VREF powered | |
192 | */ | |
193 | #define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ | |
194 | | ADS_12_BIT | ADS_SER) | |
195 | ||
de2defd9 ID |
196 | #define REF_ON (READ_12BIT_DFR(x, 1, 1)) |
197 | #define REF_OFF (READ_12BIT_DFR(y, 0, 0)) | |
ffa458c1 | 198 | |
2991a1ca JW |
199 | /* Must be called with ts->lock held */ |
200 | static void ads7846_stop(struct ads7846 *ts) | |
201 | { | |
202 | if (!ts->disabled && !ts->suspended) { | |
203 | /* Signal IRQ thread to stop polling and disable the handler. */ | |
204 | ts->stopped = true; | |
205 | mb(); | |
206 | wake_up(&ts->wait); | |
207 | disable_irq(ts->spi->irq); | |
208 | } | |
209 | } | |
210 | ||
211 | /* Must be called with ts->lock held */ | |
212 | static void ads7846_restart(struct ads7846 *ts) | |
213 | { | |
214 | if (!ts->disabled && !ts->suspended) { | |
215 | /* Tell IRQ thread that it may poll the device. */ | |
216 | ts->stopped = false; | |
217 | mb(); | |
218 | enable_irq(ts->spi->irq); | |
219 | } | |
220 | } | |
221 | ||
222 | /* Must be called with ts->lock held */ | |
223 | static void __ads7846_disable(struct ads7846 *ts) | |
224 | { | |
225 | ads7846_stop(ts); | |
226 | regulator_disable(ts->reg); | |
227 | ||
228 | /* | |
229 | * We know the chip's in low power mode since we always | |
230 | * leave it that way after every request | |
231 | */ | |
232 | } | |
233 | ||
234 | /* Must be called with ts->lock held */ | |
235 | static void __ads7846_enable(struct ads7846 *ts) | |
236 | { | |
237 | regulator_enable(ts->reg); | |
238 | ads7846_restart(ts); | |
239 | } | |
240 | ||
241 | static void ads7846_disable(struct ads7846 *ts) | |
242 | { | |
243 | mutex_lock(&ts->lock); | |
244 | ||
245 | if (!ts->disabled) { | |
246 | ||
247 | if (!ts->suspended) | |
248 | __ads7846_disable(ts); | |
249 | ||
250 | ts->disabled = true; | |
251 | } | |
252 | ||
253 | mutex_unlock(&ts->lock); | |
254 | } | |
255 | ||
256 | static void ads7846_enable(struct ads7846 *ts) | |
257 | { | |
258 | mutex_lock(&ts->lock); | |
259 | ||
260 | if (ts->disabled) { | |
261 | ||
262 | ts->disabled = false; | |
263 | ||
264 | if (!ts->suspended) | |
265 | __ads7846_enable(ts); | |
266 | } | |
267 | ||
268 | mutex_unlock(&ts->lock); | |
269 | } | |
270 | ||
ffa458c1 DB |
271 | /*--------------------------------------------------------------------------*/ |
272 | ||
273 | /* | |
274 | * Non-touchscreen sensors only use single-ended conversions. | |
2c8dc071 DB |
275 | * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; |
276 | * ads7846 lets that pin be unconnected, to use internal vREF. | |
ffa458c1 DB |
277 | */ |
278 | ||
279 | struct ser_req { | |
d93f70b2 | 280 | u8 ref_on; |
ffa458c1 | 281 | u8 command; |
d93f70b2 | 282 | u8 ref_off; |
ffa458c1 DB |
283 | u16 scratch; |
284 | __be16 sample; | |
285 | struct spi_message msg; | |
286 | struct spi_transfer xfer[6]; | |
287 | }; | |
288 | ||
3eac5c7e AG |
289 | struct ads7845_ser_req { |
290 | u8 command[3]; | |
291 | u8 pwrdown[3]; | |
292 | u8 sample[3]; | |
293 | struct spi_message msg; | |
294 | struct spi_transfer xfer[2]; | |
295 | }; | |
296 | ||
ffa458c1 DB |
297 | static int ads7846_read12_ser(struct device *dev, unsigned command) |
298 | { | |
2991a1ca JW |
299 | struct spi_device *spi = to_spi_device(dev); |
300 | struct ads7846 *ts = dev_get_drvdata(dev); | |
301 | struct ser_req *req; | |
302 | int status; | |
303 | int use_internal; | |
ffa458c1 | 304 | |
2991a1ca | 305 | req = kzalloc(sizeof *req, GFP_KERNEL); |
ffa458c1 DB |
306 | if (!req) |
307 | return -ENOMEM; | |
308 | ||
0b7018aa | 309 | spi_message_init(&req->msg); |
8275c642 | 310 | |
2c8dc071 DB |
311 | /* FIXME boards with ads7846 might use external vref instead ... */ |
312 | use_internal = (ts->model == 7846); | |
313 | ||
314 | /* maybe turn on internal vREF, and let it settle */ | |
315 | if (use_internal) { | |
316 | req->ref_on = REF_ON; | |
317 | req->xfer[0].tx_buf = &req->ref_on; | |
318 | req->xfer[0].len = 1; | |
319 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
320 | ||
321 | req->xfer[1].rx_buf = &req->scratch; | |
322 | req->xfer[1].len = 2; | |
323 | ||
324 | /* for 1uF, settle for 800 usec; no cap, 100 usec. */ | |
325 | req->xfer[1].delay_usecs = ts->vref_delay_usecs; | |
326 | spi_message_add_tail(&req->xfer[1], &req->msg); | |
327 | } | |
ffa458c1 DB |
328 | |
329 | /* take sample */ | |
330 | req->command = (u8) command; | |
331 | req->xfer[2].tx_buf = &req->command; | |
332 | req->xfer[2].len = 1; | |
2c8dc071 DB |
333 | spi_message_add_tail(&req->xfer[2], &req->msg); |
334 | ||
ffa458c1 DB |
335 | req->xfer[3].rx_buf = &req->sample; |
336 | req->xfer[3].len = 2; | |
2c8dc071 | 337 | spi_message_add_tail(&req->xfer[3], &req->msg); |
ffa458c1 DB |
338 | |
339 | /* REVISIT: take a few more samples, and compare ... */ | |
340 | ||
969111e9 NF |
341 | /* converter in low power mode & enable PENIRQ */ |
342 | req->ref_off = PWRDOWN; | |
343 | req->xfer[4].tx_buf = &req->ref_off; | |
344 | req->xfer[4].len = 1; | |
345 | spi_message_add_tail(&req->xfer[4], &req->msg); | |
346 | ||
347 | req->xfer[5].rx_buf = &req->scratch; | |
348 | req->xfer[5].len = 2; | |
349 | CS_CHANGE(req->xfer[5]); | |
350 | spi_message_add_tail(&req->xfer[5], &req->msg); | |
ffa458c1 | 351 | |
2991a1ca JW |
352 | mutex_lock(&ts->lock); |
353 | ads7846_stop(ts); | |
ffa458c1 | 354 | status = spi_sync(spi, &req->msg); |
2991a1ca JW |
355 | ads7846_restart(ts); |
356 | mutex_unlock(&ts->lock); | |
ffa458c1 | 357 | |
c24b2602 MP |
358 | if (status == 0) { |
359 | /* on-wire is a must-ignore bit, a BE12 value, then padding */ | |
7c6d0ee1 DB |
360 | status = be16_to_cpu(req->sample); |
361 | status = status >> 3; | |
362 | status &= 0x0fff; | |
c24b2602 | 363 | } |
ffa458c1 | 364 | |
9084533e | 365 | kfree(req); |
7c6d0ee1 | 366 | return status; |
ffa458c1 DB |
367 | } |
368 | ||
3eac5c7e AG |
369 | static int ads7845_read12_ser(struct device *dev, unsigned command) |
370 | { | |
2991a1ca JW |
371 | struct spi_device *spi = to_spi_device(dev); |
372 | struct ads7846 *ts = dev_get_drvdata(dev); | |
373 | struct ads7845_ser_req *req; | |
374 | int status; | |
3eac5c7e | 375 | |
2991a1ca | 376 | req = kzalloc(sizeof *req, GFP_KERNEL); |
3eac5c7e AG |
377 | if (!req) |
378 | return -ENOMEM; | |
379 | ||
380 | spi_message_init(&req->msg); | |
381 | ||
382 | req->command[0] = (u8) command; | |
383 | req->xfer[0].tx_buf = req->command; | |
384 | req->xfer[0].rx_buf = req->sample; | |
385 | req->xfer[0].len = 3; | |
386 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
387 | ||
2991a1ca JW |
388 | mutex_lock(&ts->lock); |
389 | ads7846_stop(ts); | |
3eac5c7e | 390 | status = spi_sync(spi, &req->msg); |
2991a1ca JW |
391 | ads7846_restart(ts); |
392 | mutex_unlock(&ts->lock); | |
3eac5c7e AG |
393 | |
394 | if (status == 0) { | |
395 | /* BE12 value, then padding */ | |
396 | status = be16_to_cpu(*((u16 *)&req->sample[1])); | |
397 | status = status >> 3; | |
398 | status &= 0x0fff; | |
399 | } | |
400 | ||
401 | kfree(req); | |
402 | return status; | |
403 | } | |
404 | ||
2c8dc071 DB |
405 | #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) |
406 | ||
407 | #define SHOW(name, var, adjust) static ssize_t \ | |
ffa458c1 DB |
408 | name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ |
409 | { \ | |
2c8dc071 | 410 | struct ads7846 *ts = dev_get_drvdata(dev); \ |
ffa458c1 | 411 | ssize_t v = ads7846_read12_ser(dev, \ |
2c8dc071 | 412 | READ_12BIT_SER(var) | ADS_PD10_ALL_ON); \ |
ffa458c1 DB |
413 | if (v < 0) \ |
414 | return v; \ | |
2c8dc071 | 415 | return sprintf(buf, "%u\n", adjust(ts, v)); \ |
ffa458c1 DB |
416 | } \ |
417 | static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); | |
418 | ||
2c8dc071 | 419 | |
b731d7b6 | 420 | /* Sysfs conventions report temperatures in millidegrees Celsius. |
2c8dc071 DB |
421 | * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high |
422 | * accuracy scheme without calibration data. For now we won't try either; | |
423 | * userspace sees raw sensor values, and must scale/calibrate appropriately. | |
424 | */ | |
425 | static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) | |
426 | { | |
427 | return v; | |
428 | } | |
429 | ||
430 | SHOW(temp0, temp0, null_adjust) /* temp1_input */ | |
431 | SHOW(temp1, temp1, null_adjust) /* temp2_input */ | |
432 | ||
433 | ||
434 | /* sysfs conventions report voltages in millivolts. We can convert voltages | |
435 | * if we know vREF. userspace may need to scale vAUX to match the board's | |
436 | * external resistors; we assume that vBATT only uses the internal ones. | |
437 | */ | |
438 | static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) | |
439 | { | |
440 | unsigned retval = v; | |
441 | ||
442 | /* external resistors may scale vAUX into 0..vREF */ | |
7c6d0ee1 | 443 | retval *= ts->vref_mv; |
2c8dc071 | 444 | retval = retval >> 12; |
2991a1ca | 445 | |
2c8dc071 DB |
446 | return retval; |
447 | } | |
448 | ||
449 | static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) | |
450 | { | |
451 | unsigned retval = vaux_adjust(ts, v); | |
452 | ||
453 | /* ads7846 has a resistor ladder to scale this signal down */ | |
454 | if (ts->model == 7846) | |
455 | retval *= 4; | |
2991a1ca | 456 | |
2c8dc071 DB |
457 | return retval; |
458 | } | |
459 | ||
460 | SHOW(in0_input, vaux, vaux_adjust) | |
461 | SHOW(in1_input, vbatt, vbatt_adjust) | |
462 | ||
2c8dc071 DB |
463 | static struct attribute *ads7846_attributes[] = { |
464 | &dev_attr_temp0.attr, | |
465 | &dev_attr_temp1.attr, | |
466 | &dev_attr_in0_input.attr, | |
467 | &dev_attr_in1_input.attr, | |
468 | NULL, | |
469 | }; | |
470 | ||
471 | static struct attribute_group ads7846_attr_group = { | |
472 | .attrs = ads7846_attributes, | |
473 | }; | |
474 | ||
475 | static struct attribute *ads7843_attributes[] = { | |
476 | &dev_attr_in0_input.attr, | |
477 | &dev_attr_in1_input.attr, | |
478 | NULL, | |
479 | }; | |
480 | ||
481 | static struct attribute_group ads7843_attr_group = { | |
482 | .attrs = ads7843_attributes, | |
483 | }; | |
484 | ||
485 | static struct attribute *ads7845_attributes[] = { | |
486 | &dev_attr_in0_input.attr, | |
487 | NULL, | |
488 | }; | |
489 | ||
490 | static struct attribute_group ads7845_attr_group = { | |
491 | .attrs = ads7845_attributes, | |
492 | }; | |
493 | ||
494 | static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) | |
495 | { | |
1beeffe4 | 496 | struct device *hwmon; |
2c8dc071 DB |
497 | int err; |
498 | ||
499 | /* hwmon sensors need a reference voltage */ | |
500 | switch (ts->model) { | |
501 | case 7846: | |
7c6d0ee1 | 502 | if (!ts->vref_mv) { |
2c8dc071 | 503 | dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); |
7c6d0ee1 | 504 | ts->vref_mv = 2500; |
2c8dc071 DB |
505 | } |
506 | break; | |
507 | case 7845: | |
508 | case 7843: | |
7c6d0ee1 | 509 | if (!ts->vref_mv) { |
2c8dc071 DB |
510 | dev_warn(&spi->dev, |
511 | "external vREF for ADS%d not specified\n", | |
512 | ts->model); | |
513 | return 0; | |
514 | } | |
515 | break; | |
516 | } | |
517 | ||
518 | /* different chips have different sensor groups */ | |
519 | switch (ts->model) { | |
520 | case 7846: | |
521 | ts->attr_group = &ads7846_attr_group; | |
522 | break; | |
523 | case 7845: | |
524 | ts->attr_group = &ads7845_attr_group; | |
525 | break; | |
526 | case 7843: | |
527 | ts->attr_group = &ads7843_attr_group; | |
528 | break; | |
529 | default: | |
530 | dev_dbg(&spi->dev, "ADS%d not recognized\n", ts->model); | |
531 | return 0; | |
532 | } | |
533 | ||
534 | err = sysfs_create_group(&spi->dev.kobj, ts->attr_group); | |
535 | if (err) | |
536 | return err; | |
537 | ||
538 | hwmon = hwmon_device_register(&spi->dev); | |
539 | if (IS_ERR(hwmon)) { | |
540 | sysfs_remove_group(&spi->dev.kobj, ts->attr_group); | |
541 | return PTR_ERR(hwmon); | |
542 | } | |
543 | ||
544 | ts->hwmon = hwmon; | |
545 | return 0; | |
546 | } | |
547 | ||
548 | static void ads784x_hwmon_unregister(struct spi_device *spi, | |
549 | struct ads7846 *ts) | |
550 | { | |
551 | if (ts->hwmon) { | |
552 | sysfs_remove_group(&spi->dev.kobj, ts->attr_group); | |
553 | hwmon_device_unregister(ts->hwmon); | |
554 | } | |
555 | } | |
556 | ||
557 | #else | |
558 | static inline int ads784x_hwmon_register(struct spi_device *spi, | |
559 | struct ads7846 *ts) | |
560 | { | |
561 | return 0; | |
562 | } | |
563 | ||
564 | static inline void ads784x_hwmon_unregister(struct spi_device *spi, | |
565 | struct ads7846 *ts) | |
566 | { | |
567 | } | |
568 | #endif | |
ffa458c1 | 569 | |
438f2a74 ID |
570 | static ssize_t ads7846_pen_down_show(struct device *dev, |
571 | struct device_attribute *attr, char *buf) | |
572 | { | |
2991a1ca JW |
573 | struct ads7846 *ts = dev_get_drvdata(dev); |
574 | ||
575 | return sprintf(buf, "%u\n", ts->pendown); | |
438f2a74 ID |
576 | } |
577 | ||
578 | static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); | |
579 | ||
7de90a8c ID |
580 | static ssize_t ads7846_disable_show(struct device *dev, |
581 | struct device_attribute *attr, char *buf) | |
582 | { | |
2991a1ca | 583 | struct ads7846 *ts = dev_get_drvdata(dev); |
7de90a8c ID |
584 | |
585 | return sprintf(buf, "%u\n", ts->disabled); | |
586 | } | |
587 | ||
588 | static ssize_t ads7846_disable_store(struct device *dev, | |
589 | struct device_attribute *attr, | |
590 | const char *buf, size_t count) | |
591 | { | |
592 | struct ads7846 *ts = dev_get_drvdata(dev); | |
3a0c58dd | 593 | unsigned long i; |
160f1fef JR |
594 | |
595 | if (strict_strtoul(buf, 10, &i)) | |
596 | return -EINVAL; | |
7de90a8c | 597 | |
7de90a8c ID |
598 | if (i) |
599 | ads7846_disable(ts); | |
600 | else | |
601 | ads7846_enable(ts); | |
602 | ||
7de90a8c ID |
603 | return count; |
604 | } | |
605 | ||
606 | static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); | |
607 | ||
2c8dc071 | 608 | static struct attribute *ads784x_attributes[] = { |
8dd51650 DT |
609 | &dev_attr_pen_down.attr, |
610 | &dev_attr_disable.attr, | |
611 | NULL, | |
612 | }; | |
613 | ||
2c8dc071 DB |
614 | static struct attribute_group ads784x_attr_group = { |
615 | .attrs = ads784x_attributes, | |
8dd51650 DT |
616 | }; |
617 | ||
ffa458c1 DB |
618 | /*--------------------------------------------------------------------------*/ |
619 | ||
4d5975e5 EM |
620 | static int get_pendown_state(struct ads7846 *ts) |
621 | { | |
622 | if (ts->get_pendown_state) | |
623 | return ts->get_pendown_state(); | |
624 | ||
625 | return !gpio_get_value(ts->gpio_pendown); | |
626 | } | |
627 | ||
fd746d54 EM |
628 | static void null_wait_for_sync(void) |
629 | { | |
630 | } | |
631 | ||
2991a1ca JW |
632 | static int ads7846_debounce_filter(void *ads, int data_idx, int *val) |
633 | { | |
634 | struct ads7846 *ts = ads; | |
635 | ||
636 | if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { | |
637 | /* Start over collecting consistent readings. */ | |
638 | ts->read_rep = 0; | |
639 | /* | |
640 | * Repeat it, if this was the first read or the read | |
641 | * wasn't consistent enough. | |
642 | */ | |
643 | if (ts->read_cnt < ts->debounce_max) { | |
644 | ts->last_read = *val; | |
645 | ts->read_cnt++; | |
646 | return ADS7846_FILTER_REPEAT; | |
647 | } else { | |
648 | /* | |
649 | * Maximum number of debouncing reached and still | |
650 | * not enough number of consistent readings. Abort | |
651 | * the whole sample, repeat it in the next sampling | |
652 | * period. | |
653 | */ | |
654 | ts->read_cnt = 0; | |
655 | return ADS7846_FILTER_IGNORE; | |
656 | } | |
657 | } else { | |
658 | if (++ts->read_rep > ts->debounce_rep) { | |
659 | /* | |
660 | * Got a good reading for this coordinate, | |
661 | * go for the next one. | |
662 | */ | |
663 | ts->read_cnt = 0; | |
664 | ts->read_rep = 0; | |
665 | return ADS7846_FILTER_OK; | |
666 | } else { | |
667 | /* Read more values that are consistent. */ | |
668 | ts->read_cnt++; | |
669 | return ADS7846_FILTER_REPEAT; | |
670 | } | |
671 | } | |
672 | } | |
673 | ||
674 | static int ads7846_no_filter(void *ads, int data_idx, int *val) | |
675 | { | |
676 | return ADS7846_FILTER_OK; | |
677 | } | |
678 | ||
679 | static int ads7846_get_value(struct ads7846 *ts, struct spi_message *m) | |
680 | { | |
681 | struct spi_transfer *t = | |
682 | list_entry(m->transfers.prev, struct spi_transfer, transfer_list); | |
683 | ||
684 | if (ts->model == 7845) { | |
685 | return be16_to_cpup((__be16 *)&(((char*)t->rx_buf)[1])) >> 3; | |
686 | } else { | |
687 | /* | |
688 | * adjust: on-wire is a must-ignore bit, a BE12 value, then | |
689 | * padding; built from two 8 bit values written msb-first. | |
690 | */ | |
691 | return be16_to_cpup((__be16 *)t->rx_buf) >> 3; | |
692 | } | |
693 | } | |
694 | ||
695 | static void ads7846_update_value(struct spi_message *m, int val) | |
696 | { | |
697 | struct spi_transfer *t = | |
698 | list_entry(m->transfers.prev, struct spi_transfer, transfer_list); | |
699 | ||
700 | *(u16 *)t->rx_buf = val; | |
701 | } | |
702 | ||
703 | static void ads7846_read_state(struct ads7846 *ts) | |
704 | { | |
705 | struct ads7846_packet *packet = ts->packet; | |
706 | struct spi_message *m; | |
707 | int msg_idx = 0; | |
708 | int val; | |
709 | int action; | |
710 | int error; | |
711 | ||
712 | while (msg_idx < ts->msg_count) { | |
713 | ||
714 | ts->wait_for_sync(); | |
715 | ||
716 | m = &ts->msg[msg_idx]; | |
717 | error = spi_sync(ts->spi, m); | |
718 | if (error) { | |
719 | dev_err(&ts->spi->dev, "spi_async --> %d\n", error); | |
720 | packet->tc.ignore = true; | |
721 | return; | |
722 | } | |
723 | ||
724 | /* | |
725 | * Last message is power down request, no need to convert | |
726 | * or filter the value. | |
727 | */ | |
728 | if (msg_idx < ts->msg_count - 1) { | |
ffa458c1 | 729 | |
2991a1ca JW |
730 | val = ads7846_get_value(ts, m); |
731 | ||
732 | action = ts->filter(ts->filter_data, msg_idx, &val); | |
733 | switch (action) { | |
734 | case ADS7846_FILTER_REPEAT: | |
735 | continue; | |
736 | ||
737 | case ADS7846_FILTER_IGNORE: | |
738 | packet->tc.ignore = true; | |
739 | msg_idx = ts->msg_count - 1; | |
740 | continue; | |
741 | ||
742 | case ADS7846_FILTER_OK: | |
743 | ads7846_update_value(m, val); | |
744 | packet->tc.ignore = false; | |
745 | msg_idx++; | |
746 | break; | |
747 | ||
748 | default: | |
749 | BUG(); | |
750 | } | |
751 | } else { | |
752 | msg_idx++; | |
753 | } | |
754 | } | |
755 | } | |
756 | ||
757 | static void ads7846_report_state(struct ads7846 *ts) | |
ffa458c1 | 758 | { |
2991a1ca JW |
759 | struct ads7846_packet *packet = ts->packet; |
760 | unsigned int Rt; | |
761 | u16 x, y, z1, z2; | |
ffa458c1 | 762 | |
2991a1ca JW |
763 | /* |
764 | * ads7846_get_value() does in-place conversion (including byte swap) | |
765 | * from on-the-wire format as part of debouncing to get stable | |
766 | * readings. | |
ffa458c1 | 767 | */ |
3eac5c7e AG |
768 | if (ts->model == 7845) { |
769 | x = *(u16 *)packet->tc.x_buf; | |
770 | y = *(u16 *)packet->tc.y_buf; | |
771 | z1 = 0; | |
772 | z2 = 0; | |
773 | } else { | |
774 | x = packet->tc.x; | |
775 | y = packet->tc.y; | |
776 | z1 = packet->tc.z1; | |
777 | z2 = packet->tc.z2; | |
778 | } | |
ffa458c1 DB |
779 | |
780 | /* range filtering */ | |
781 | if (x == MAX_12BIT) | |
782 | x = 0; | |
783 | ||
9460b652 HCE |
784 | if (ts->model == 7843) { |
785 | Rt = ts->pressure_max / 2; | |
3eac5c7e AG |
786 | } else if (ts->model == 7845) { |
787 | if (get_pendown_state(ts)) | |
788 | Rt = ts->pressure_max / 2; | |
789 | else | |
790 | Rt = 0; | |
791 | dev_vdbg(&ts->spi->dev, "x/y: %d/%d, PD %d\n", x, y, Rt); | |
9460b652 | 792 | } else if (likely(x && z1)) { |
ffa458c1 DB |
793 | /* compute touch pressure resistance using equation #2 */ |
794 | Rt = z2; | |
795 | Rt -= z1; | |
796 | Rt *= x; | |
797 | Rt *= ts->x_plate_ohms; | |
798 | Rt /= z1; | |
799 | Rt = (Rt + 2047) >> 12; | |
9460b652 | 800 | } else { |
ffa458c1 | 801 | Rt = 0; |
9460b652 | 802 | } |
969111e9 | 803 | |
2991a1ca JW |
804 | /* |
805 | * Sample found inconsistent by debouncing or pressure is beyond | |
1936d590 ID |
806 | * the maximum. Don't report it to user space, repeat at least |
807 | * once more the measurement | |
808 | */ | |
e8f462d2 | 809 | if (packet->tc.ignore || Rt > ts->pressure_max) { |
52ce4eaa PM |
810 | dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", |
811 | packet->tc.ignore, Rt); | |
d5b415c9 ID |
812 | return; |
813 | } | |
814 | ||
2991a1ca JW |
815 | /* |
816 | * Maybe check the pendown state before reporting. This discards | |
1d25891f SH |
817 | * false readings when the pen is lifted. |
818 | */ | |
819 | if (ts->penirq_recheck_delay_usecs) { | |
820 | udelay(ts->penirq_recheck_delay_usecs); | |
4d5975e5 | 821 | if (!get_pendown_state(ts)) |
1d25891f SH |
822 | Rt = 0; |
823 | } | |
824 | ||
2991a1ca JW |
825 | /* |
826 | * NOTE: We can't rely on the pressure to determine the pen down | |
827 | * state, even this controller has a pressure sensor. The pressure | |
15e3589e ID |
828 | * value can fluctuate for quite a while after lifting the pen and |
829 | * in some cases may not even settle at the expected value. | |
ffa458c1 | 830 | * |
15e3589e ID |
831 | * The only safe way to check for the pen up condition is in the |
832 | * timer by reading the pen signal state (it's a GPIO _and_ IRQ). | |
ffa458c1 | 833 | */ |
ffa458c1 | 834 | if (Rt) { |
15e3589e | 835 | struct input_dev *input = ts->input; |
ae82d5ab | 836 | |
2991a1ca JW |
837 | if (ts->swap_xy) |
838 | swap(x, y); | |
839 | ||
15e3589e ID |
840 | if (!ts->pendown) { |
841 | input_report_key(input, BTN_TOUCH, 1); | |
2991a1ca | 842 | ts->pendown = true; |
52ce4eaa | 843 | dev_vdbg(&ts->spi->dev, "DOWN\n"); |
15e3589e | 844 | } |
86579a4c | 845 | |
15e3589e ID |
846 | input_report_abs(input, ABS_X, x); |
847 | input_report_abs(input, ABS_Y, y); | |
30ad7ba0 | 848 | input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); |
ffa458c1 | 849 | |
15e3589e | 850 | input_sync(input); |
52ce4eaa | 851 | dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); |
15e3589e | 852 | } |
da970e69 ID |
853 | } |
854 | ||
2991a1ca | 855 | static irqreturn_t ads7846_hard_irq(int irq, void *handle) |
da970e69 | 856 | { |
2991a1ca | 857 | struct ads7846 *ts = handle; |
da970e69 | 858 | |
2991a1ca | 859 | return get_pendown_state(ts) ? IRQ_WAKE_THREAD : IRQ_HANDLED; |
0b7018aa ID |
860 | } |
861 | ||
0b7018aa | 862 | |
7d12e780 | 863 | static irqreturn_t ads7846_irq(int irq, void *handle) |
0b7018aa ID |
864 | { |
865 | struct ads7846 *ts = handle; | |
7de90a8c | 866 | |
2991a1ca JW |
867 | /* Start with a small delay before checking pendown state */ |
868 | msleep(TS_POLL_DELAY); | |
ffa458c1 | 869 | |
2991a1ca | 870 | while (!ts->stopped && get_pendown_state(ts)) { |
ffa458c1 | 871 | |
2991a1ca JW |
872 | /* pen is down, continue with the measurement */ |
873 | ads7846_read_state(ts); | |
ffa458c1 | 874 | |
2991a1ca JW |
875 | if (!ts->stopped) |
876 | ads7846_report_state(ts); | |
c9e617a5 | 877 | |
2991a1ca JW |
878 | wait_event_timeout(ts->wait, ts->stopped, |
879 | msecs_to_jiffies(TS_POLL_PERIOD)); | |
ffa458c1 DB |
880 | } |
881 | ||
2991a1ca JW |
882 | if (ts->pendown) { |
883 | struct input_dev *input = ts->input; | |
7de90a8c | 884 | |
2991a1ca JW |
885 | input_report_key(input, BTN_TOUCH, 0); |
886 | input_report_abs(input, ABS_PRESSURE, 0); | |
887 | input_sync(input); | |
7de90a8c | 888 | |
2991a1ca JW |
889 | ts->pendown = false; |
890 | dev_vdbg(&ts->spi->dev, "UP\n"); | |
891 | } | |
91143379 | 892 | |
2991a1ca | 893 | return IRQ_HANDLED; |
7de90a8c ID |
894 | } |
895 | ||
3c36e719 MB |
896 | #ifdef CONFIG_PM_SLEEP |
897 | static int ads7846_suspend(struct device *dev) | |
7de90a8c | 898 | { |
3c36e719 | 899 | struct ads7846 *ts = dev_get_drvdata(dev); |
7de90a8c | 900 | |
2991a1ca | 901 | mutex_lock(&ts->lock); |
7de90a8c | 902 | |
2991a1ca | 903 | if (!ts->suspended) { |
7de90a8c | 904 | |
2991a1ca JW |
905 | if (!ts->disabled) |
906 | __ads7846_disable(ts); | |
7de90a8c | 907 | |
2991a1ca JW |
908 | if (device_may_wakeup(&ts->spi->dev)) |
909 | enable_irq_wake(ts->spi->irq); | |
fdba2bb1 | 910 | |
2991a1ca JW |
911 | ts->suspended = true; |
912 | } | |
913 | ||
914 | mutex_unlock(&ts->lock); | |
7de90a8c | 915 | |
2991a1ca | 916 | return 0; |
ffa458c1 DB |
917 | } |
918 | ||
3c36e719 | 919 | static int ads7846_resume(struct device *dev) |
ffa458c1 | 920 | { |
3c36e719 | 921 | struct ads7846 *ts = dev_get_drvdata(dev); |
ffa458c1 | 922 | |
2991a1ca JW |
923 | mutex_lock(&ts->lock); |
924 | ||
925 | if (ts->suspended) { | |
fdba2bb1 | 926 | |
2991a1ca | 927 | ts->suspended = false; |
7de90a8c | 928 | |
2991a1ca JW |
929 | if (device_may_wakeup(&ts->spi->dev)) |
930 | disable_irq_wake(ts->spi->irq); | |
7de90a8c | 931 | |
2991a1ca JW |
932 | if (!ts->disabled) |
933 | __ads7846_enable(ts); | |
934 | } | |
935 | ||
936 | mutex_unlock(&ts->lock); | |
7de90a8c | 937 | |
ffa458c1 DB |
938 | return 0; |
939 | } | |
3c36e719 MB |
940 | #endif |
941 | ||
942 | static SIMPLE_DEV_PM_OPS(ads7846_pm, ads7846_suspend, ads7846_resume); | |
ffa458c1 | 943 | |
2991a1ca | 944 | static int __devinit ads7846_setup_pendown(struct spi_device *spi, struct ads7846 *ts) |
4d5975e5 EM |
945 | { |
946 | struct ads7846_platform_data *pdata = spi->dev.platform_data; | |
947 | int err; | |
948 | ||
0fbc9fdb DT |
949 | /* |
950 | * REVISIT when the irq can be triggered active-low, or if for some | |
4d5975e5 EM |
951 | * reason the touchscreen isn't hooked up, we don't need to access |
952 | * the pendown state. | |
953 | */ | |
4d5975e5 EM |
954 | |
955 | if (pdata->get_pendown_state) { | |
956 | ts->get_pendown_state = pdata->get_pendown_state; | |
0fbc9fdb | 957 | } else if (gpio_is_valid(pdata->gpio_pendown)) { |
4d5975e5 | 958 | |
0fbc9fdb DT |
959 | err = gpio_request(pdata->gpio_pendown, "ads7846_pendown"); |
960 | if (err) { | |
961 | dev_err(&spi->dev, "failed to request pendown GPIO%d\n", | |
962 | pdata->gpio_pendown); | |
963 | return err; | |
964 | } | |
4d5975e5 | 965 | |
0fbc9fdb DT |
966 | ts->gpio_pendown = pdata->gpio_pendown; |
967 | ||
968 | } else { | |
969 | dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); | |
970 | return -EINVAL; | |
971 | } | |
2991a1ca | 972 | |
4d5975e5 EM |
973 | return 0; |
974 | } | |
975 | ||
2991a1ca JW |
976 | /* |
977 | * Set up the transfers to read touchscreen state; this assumes we | |
978 | * use formula #2 for pressure, not #3. | |
979 | */ | |
980 | static void __devinit ads7846_setup_spi_msg(struct ads7846 *ts, | |
981 | const struct ads7846_platform_data *pdata) | |
ffa458c1 | 982 | { |
2991a1ca JW |
983 | struct spi_message *m = &ts->msg[0]; |
984 | struct spi_transfer *x = ts->xfer; | |
985 | struct ads7846_packet *packet = ts->packet; | |
986 | int vref = pdata->keep_vref_on; | |
de2defd9 | 987 | |
06a09124 | 988 | if (ts->model == 7873) { |
2991a1ca JW |
989 | /* |
990 | * The AD7873 is almost identical to the ADS7846 | |
06a09124 | 991 | * keep VREF off during differential/ratiometric |
2991a1ca | 992 | * conversion modes. |
06a09124 MH |
993 | */ |
994 | ts->model = 7846; | |
995 | vref = 0; | |
996 | } | |
997 | ||
2991a1ca | 998 | ts->msg_count = 1; |
0b7018aa | 999 | spi_message_init(m); |
2991a1ca | 1000 | m->context = ts; |
0b7018aa | 1001 | |
3eac5c7e AG |
1002 | if (ts->model == 7845) { |
1003 | packet->read_y_cmd[0] = READ_Y(vref); | |
1004 | packet->read_y_cmd[1] = 0; | |
1005 | packet->read_y_cmd[2] = 0; | |
1006 | x->tx_buf = &packet->read_y_cmd[0]; | |
1007 | x->rx_buf = &packet->tc.y_buf[0]; | |
1008 | x->len = 3; | |
1009 | spi_message_add_tail(x, m); | |
1010 | } else { | |
1011 | /* y- still on; turn on only y+ (and ADC) */ | |
1012 | packet->read_y = READ_Y(vref); | |
1013 | x->tx_buf = &packet->read_y; | |
1014 | x->len = 1; | |
1015 | spi_message_add_tail(x, m); | |
d93f70b2 | 1016 | |
3eac5c7e AG |
1017 | x++; |
1018 | x->rx_buf = &packet->tc.y; | |
1019 | x->len = 2; | |
1020 | spi_message_add_tail(x, m); | |
1021 | } | |
0b7018aa | 1022 | |
2991a1ca JW |
1023 | /* |
1024 | * The first sample after switching drivers can be low quality; | |
e4f48861 SH |
1025 | * optionally discard it, using a second one after the signals |
1026 | * have had enough time to stabilize. | |
1027 | */ | |
1028 | if (pdata->settle_delay_usecs) { | |
1029 | x->delay_usecs = pdata->settle_delay_usecs; | |
1030 | ||
1031 | x++; | |
e8f462d2 | 1032 | x->tx_buf = &packet->read_y; |
e4f48861 SH |
1033 | x->len = 1; |
1034 | spi_message_add_tail(x, m); | |
1035 | ||
1036 | x++; | |
e8f462d2 | 1037 | x->rx_buf = &packet->tc.y; |
e4f48861 SH |
1038 | x->len = 2; |
1039 | spi_message_add_tail(x, m); | |
1040 | } | |
1041 | ||
2991a1ca | 1042 | ts->msg_count++; |
0b7018aa ID |
1043 | m++; |
1044 | spi_message_init(m); | |
2991a1ca | 1045 | m->context = ts; |
0b7018aa | 1046 | |
3eac5c7e AG |
1047 | if (ts->model == 7845) { |
1048 | x++; | |
1049 | packet->read_x_cmd[0] = READ_X(vref); | |
1050 | packet->read_x_cmd[1] = 0; | |
1051 | packet->read_x_cmd[2] = 0; | |
1052 | x->tx_buf = &packet->read_x_cmd[0]; | |
1053 | x->rx_buf = &packet->tc.x_buf[0]; | |
1054 | x->len = 3; | |
1055 | spi_message_add_tail(x, m); | |
1056 | } else { | |
1057 | /* turn y- off, x+ on, then leave in lowpower */ | |
1058 | x++; | |
1059 | packet->read_x = READ_X(vref); | |
1060 | x->tx_buf = &packet->read_x; | |
1061 | x->len = 1; | |
1062 | spi_message_add_tail(x, m); | |
0b7018aa | 1063 | |
3eac5c7e AG |
1064 | x++; |
1065 | x->rx_buf = &packet->tc.x; | |
1066 | x->len = 2; | |
1067 | spi_message_add_tail(x, m); | |
1068 | } | |
0b7018aa | 1069 | |
e4f48861 SH |
1070 | /* ... maybe discard first sample ... */ |
1071 | if (pdata->settle_delay_usecs) { | |
1072 | x->delay_usecs = pdata->settle_delay_usecs; | |
1073 | ||
1074 | x++; | |
e8f462d2 | 1075 | x->tx_buf = &packet->read_x; |
e4f48861 SH |
1076 | x->len = 1; |
1077 | spi_message_add_tail(x, m); | |
1078 | ||
1079 | x++; | |
e8f462d2 | 1080 | x->rx_buf = &packet->tc.x; |
e4f48861 SH |
1081 | x->len = 2; |
1082 | spi_message_add_tail(x, m); | |
1083 | } | |
1084 | ||
ffa458c1 DB |
1085 | /* turn y+ off, x- on; we'll use formula #2 */ |
1086 | if (ts->model == 7846) { | |
2991a1ca | 1087 | ts->msg_count++; |
0b7018aa ID |
1088 | m++; |
1089 | spi_message_init(m); | |
2991a1ca | 1090 | m->context = ts; |
0b7018aa | 1091 | |
d93f70b2 | 1092 | x++; |
e8f462d2 DT |
1093 | packet->read_z1 = READ_Z1(vref); |
1094 | x->tx_buf = &packet->read_z1; | |
ffa458c1 | 1095 | x->len = 1; |
0b7018aa | 1096 | spi_message_add_tail(x, m); |
d93f70b2 | 1097 | |
ffa458c1 | 1098 | x++; |
e8f462d2 | 1099 | x->rx_buf = &packet->tc.z1; |
ffa458c1 | 1100 | x->len = 2; |
0b7018aa ID |
1101 | spi_message_add_tail(x, m); |
1102 | ||
e4f48861 SH |
1103 | /* ... maybe discard first sample ... */ |
1104 | if (pdata->settle_delay_usecs) { | |
1105 | x->delay_usecs = pdata->settle_delay_usecs; | |
1106 | ||
1107 | x++; | |
e8f462d2 | 1108 | x->tx_buf = &packet->read_z1; |
e4f48861 SH |
1109 | x->len = 1; |
1110 | spi_message_add_tail(x, m); | |
1111 | ||
1112 | x++; | |
e8f462d2 | 1113 | x->rx_buf = &packet->tc.z1; |
e4f48861 SH |
1114 | x->len = 2; |
1115 | spi_message_add_tail(x, m); | |
1116 | } | |
1117 | ||
2991a1ca | 1118 | ts->msg_count++; |
0b7018aa ID |
1119 | m++; |
1120 | spi_message_init(m); | |
2991a1ca | 1121 | m->context = ts; |
ffa458c1 | 1122 | |
d93f70b2 | 1123 | x++; |
e8f462d2 DT |
1124 | packet->read_z2 = READ_Z2(vref); |
1125 | x->tx_buf = &packet->read_z2; | |
ffa458c1 | 1126 | x->len = 1; |
0b7018aa | 1127 | spi_message_add_tail(x, m); |
d93f70b2 | 1128 | |
ffa458c1 | 1129 | x++; |
e8f462d2 | 1130 | x->rx_buf = &packet->tc.z2; |
ffa458c1 | 1131 | x->len = 2; |
0b7018aa | 1132 | spi_message_add_tail(x, m); |
ffa458c1 | 1133 | |
e4f48861 SH |
1134 | /* ... maybe discard first sample ... */ |
1135 | if (pdata->settle_delay_usecs) { | |
1136 | x->delay_usecs = pdata->settle_delay_usecs; | |
1137 | ||
1138 | x++; | |
e8f462d2 | 1139 | x->tx_buf = &packet->read_z2; |
e4f48861 SH |
1140 | x->len = 1; |
1141 | spi_message_add_tail(x, m); | |
1142 | ||
1143 | x++; | |
e8f462d2 | 1144 | x->rx_buf = &packet->tc.z2; |
e4f48861 SH |
1145 | x->len = 2; |
1146 | spi_message_add_tail(x, m); | |
1147 | } | |
0b7018aa | 1148 | } |
53a0ef89 ID |
1149 | |
1150 | /* power down */ | |
2991a1ca | 1151 | ts->msg_count++; |
0b7018aa ID |
1152 | m++; |
1153 | spi_message_init(m); | |
2991a1ca | 1154 | m->context = ts; |
0b7018aa | 1155 | |
3eac5c7e AG |
1156 | if (ts->model == 7845) { |
1157 | x++; | |
1158 | packet->pwrdown_cmd[0] = PWRDOWN; | |
1159 | packet->pwrdown_cmd[1] = 0; | |
1160 | packet->pwrdown_cmd[2] = 0; | |
1161 | x->tx_buf = &packet->pwrdown_cmd[0]; | |
1162 | x->len = 3; | |
1163 | } else { | |
1164 | x++; | |
1165 | packet->pwrdown = PWRDOWN; | |
1166 | x->tx_buf = &packet->pwrdown; | |
1167 | x->len = 1; | |
1168 | spi_message_add_tail(x, m); | |
1169 | ||
1170 | x++; | |
1171 | x->rx_buf = &packet->dummy; | |
1172 | x->len = 2; | |
1173 | } | |
53a0ef89 | 1174 | |
d93f70b2 | 1175 | CS_CHANGE(*x); |
0b7018aa | 1176 | spi_message_add_tail(x, m); |
2991a1ca | 1177 | } |
ffa458c1 | 1178 | |
2991a1ca JW |
1179 | static int __devinit ads7846_probe(struct spi_device *spi) |
1180 | { | |
1181 | struct ads7846 *ts; | |
1182 | struct ads7846_packet *packet; | |
1183 | struct input_dev *input_dev; | |
1184 | struct ads7846_platform_data *pdata = spi->dev.platform_data; | |
1185 | unsigned long irq_flags; | |
1186 | int err; | |
1187 | ||
1188 | if (!spi->irq) { | |
1189 | dev_dbg(&spi->dev, "no IRQ?\n"); | |
1190 | return -ENODEV; | |
1191 | } | |
1192 | ||
1193 | if (!pdata) { | |
1194 | dev_dbg(&spi->dev, "no platform data?\n"); | |
1195 | return -ENODEV; | |
1196 | } | |
1197 | ||
1198 | /* don't exceed max specified sample rate */ | |
1199 | if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { | |
1200 | dev_dbg(&spi->dev, "f(sample) %d KHz?\n", | |
1201 | (spi->max_speed_hz/SAMPLE_BITS)/1000); | |
1202 | return -EINVAL; | |
1203 | } | |
1204 | ||
1205 | /* We'd set TX word size 8 bits and RX word size to 13 bits ... except | |
1206 | * that even if the hardware can do that, the SPI controller driver | |
1207 | * may not. So we stick to very-portable 8 bit words, both RX and TX. | |
1208 | */ | |
1209 | spi->bits_per_word = 8; | |
1210 | spi->mode = SPI_MODE_0; | |
1211 | err = spi_setup(spi); | |
1212 | if (err < 0) | |
1213 | return err; | |
ffa458c1 | 1214 | |
2991a1ca JW |
1215 | ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); |
1216 | packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); | |
1217 | input_dev = input_allocate_device(); | |
1218 | if (!ts || !packet || !input_dev) { | |
1219 | err = -ENOMEM; | |
1220 | goto err_free_mem; | |
1221 | } | |
1222 | ||
1223 | dev_set_drvdata(&spi->dev, ts); | |
1224 | ||
1225 | ts->packet = packet; | |
1226 | ts->spi = spi; | |
1227 | ts->input = input_dev; | |
1228 | ts->vref_mv = pdata->vref_mv; | |
1229 | ts->swap_xy = pdata->swap_xy; | |
1230 | ||
1231 | mutex_init(&ts->lock); | |
1232 | init_waitqueue_head(&ts->wait); | |
1233 | ||
1234 | ts->model = pdata->model ? : 7846; | |
1235 | ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; | |
1236 | ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; | |
1237 | ts->pressure_max = pdata->pressure_max ? : ~0; | |
1238 | ||
1239 | if (pdata->filter != NULL) { | |
1240 | if (pdata->filter_init != NULL) { | |
1241 | err = pdata->filter_init(pdata, &ts->filter_data); | |
1242 | if (err < 0) | |
1243 | goto err_free_mem; | |
1244 | } | |
1245 | ts->filter = pdata->filter; | |
1246 | ts->filter_cleanup = pdata->filter_cleanup; | |
1247 | } else if (pdata->debounce_max) { | |
1248 | ts->debounce_max = pdata->debounce_max; | |
1249 | if (ts->debounce_max < 2) | |
1250 | ts->debounce_max = 2; | |
1251 | ts->debounce_tol = pdata->debounce_tol; | |
1252 | ts->debounce_rep = pdata->debounce_rep; | |
1253 | ts->filter = ads7846_debounce_filter; | |
1254 | ts->filter_data = ts; | |
1255 | } else { | |
1256 | ts->filter = ads7846_no_filter; | |
1257 | } | |
1258 | ||
1259 | err = ads7846_setup_pendown(spi, ts); | |
1260 | if (err) | |
1261 | goto err_cleanup_filter; | |
1262 | ||
1263 | if (pdata->penirq_recheck_delay_usecs) | |
1264 | ts->penirq_recheck_delay_usecs = | |
1265 | pdata->penirq_recheck_delay_usecs; | |
1266 | ||
1267 | ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; | |
1268 | ||
1269 | snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); | |
1270 | snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); | |
1271 | ||
1272 | input_dev->name = ts->name; | |
1273 | input_dev->phys = ts->phys; | |
1274 | input_dev->dev.parent = &spi->dev; | |
1275 | ||
1276 | input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); | |
1277 | input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); | |
1278 | input_set_abs_params(input_dev, ABS_X, | |
1279 | pdata->x_min ? : 0, | |
1280 | pdata->x_max ? : MAX_12BIT, | |
1281 | 0, 0); | |
1282 | input_set_abs_params(input_dev, ABS_Y, | |
1283 | pdata->y_min ? : 0, | |
1284 | pdata->y_max ? : MAX_12BIT, | |
1285 | 0, 0); | |
1286 | input_set_abs_params(input_dev, ABS_PRESSURE, | |
1287 | pdata->pressure_min, pdata->pressure_max, 0, 0); | |
1288 | ||
1289 | ads7846_setup_spi_msg(ts, pdata); | |
d5b415c9 | 1290 | |
91143379 GI |
1291 | ts->reg = regulator_get(&spi->dev, "vcc"); |
1292 | if (IS_ERR(ts->reg)) { | |
067fb2f6 | 1293 | err = PTR_ERR(ts->reg); |
56960b36 | 1294 | dev_err(&spi->dev, "unable to get regulator: %d\n", err); |
91143379 GI |
1295 | goto err_free_gpio; |
1296 | } | |
1297 | ||
1298 | err = regulator_enable(ts->reg); | |
1299 | if (err) { | |
1300 | dev_err(&spi->dev, "unable to enable regulator: %d\n", err); | |
1301 | goto err_put_regulator; | |
1302 | } | |
1303 | ||
0f622bf4 | 1304 | irq_flags = pdata->irq_flags ? : IRQF_TRIGGER_FALLING; |
2991a1ca | 1305 | irq_flags |= IRQF_ONESHOT; |
7804302b | 1306 | |
2991a1ca JW |
1307 | err = request_threaded_irq(spi->irq, ads7846_hard_irq, ads7846_irq, |
1308 | irq_flags, spi->dev.driver->name, ts); | |
0f622bf4 | 1309 | if (err && !pdata->irq_flags) { |
c57c0a2a MR |
1310 | dev_info(&spi->dev, |
1311 | "trying pin change workaround on irq %d\n", spi->irq); | |
2991a1ca JW |
1312 | irq_flags |= IRQF_TRIGGER_RISING; |
1313 | err = request_threaded_irq(spi->irq, | |
1314 | ads7846_hard_irq, ads7846_irq, | |
1315 | irq_flags, spi->dev.driver->name, ts); | |
0f622bf4 DT |
1316 | } |
1317 | ||
1318 | if (err) { | |
1319 | dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); | |
1320 | goto err_disable_regulator; | |
ffa458c1 | 1321 | } |
ffa458c1 | 1322 | |
2c8dc071 DB |
1323 | err = ads784x_hwmon_register(spi, ts); |
1324 | if (err) | |
1325 | goto err_free_irq; | |
1326 | ||
2e5a7bd9 | 1327 | dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); |
ffa458c1 | 1328 | |
2991a1ca JW |
1329 | /* |
1330 | * Take a first sample, leaving nPENIRQ active and vREF off; avoid | |
ffa458c1 DB |
1331 | * the touchscreen, in case it's not connected. |
1332 | */ | |
3eac5c7e AG |
1333 | if (ts->model == 7845) |
1334 | ads7845_read12_ser(&spi->dev, PWRDOWN); | |
1335 | else | |
1336 | (void) ads7846_read12_ser(&spi->dev, | |
1337 | READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON); | |
ffa458c1 | 1338 | |
2c8dc071 | 1339 | err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); |
8dd51650 | 1340 | if (err) |
2c8dc071 | 1341 | goto err_remove_hwmon; |
7de90a8c | 1342 | |
a90f7e98 DT |
1343 | err = input_register_device(input_dev); |
1344 | if (err) | |
8dd51650 | 1345 | goto err_remove_attr_group; |
a90f7e98 | 1346 | |
fdba2bb1 RL |
1347 | device_init_wakeup(&spi->dev, pdata->wakeup); |
1348 | ||
ffa458c1 | 1349 | return 0; |
a90f7e98 | 1350 | |
8dd51650 | 1351 | err_remove_attr_group: |
2c8dc071 DB |
1352 | sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
1353 | err_remove_hwmon: | |
1354 | ads784x_hwmon_unregister(spi, ts); | |
8dd51650 | 1355 | err_free_irq: |
a90f7e98 | 1356 | free_irq(spi->irq, ts); |
91143379 GI |
1357 | err_disable_regulator: |
1358 | regulator_disable(ts->reg); | |
1359 | err_put_regulator: | |
1360 | regulator_put(ts->reg); | |
4d5975e5 | 1361 | err_free_gpio: |
0fbc9fdb | 1362 | if (!ts->get_pendown_state) |
4d5975e5 | 1363 | gpio_free(ts->gpio_pendown); |
da970e69 ID |
1364 | err_cleanup_filter: |
1365 | if (ts->filter_cleanup) | |
1366 | ts->filter_cleanup(ts->filter_data); | |
a90f7e98 DT |
1367 | err_free_mem: |
1368 | input_free_device(input_dev); | |
e8f462d2 | 1369 | kfree(packet); |
a90f7e98 DT |
1370 | kfree(ts); |
1371 | return err; | |
ffa458c1 DB |
1372 | } |
1373 | ||
2e5a7bd9 | 1374 | static int __devexit ads7846_remove(struct spi_device *spi) |
ffa458c1 | 1375 | { |
2991a1ca | 1376 | struct ads7846 *ts = dev_get_drvdata(&spi->dev); |
ffa458c1 | 1377 | |
fdba2bb1 RL |
1378 | device_init_wakeup(&spi->dev, false); |
1379 | ||
2c8dc071 | 1380 | sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
ffa458c1 | 1381 | |
2991a1ca | 1382 | ads7846_disable(ts); |
7de90a8c | 1383 | free_irq(ts->spi->irq, ts); |
2991a1ca JW |
1384 | |
1385 | input_unregister_device(ts->input); | |
1386 | ||
1387 | ads784x_hwmon_unregister(spi, ts); | |
7de90a8c | 1388 | |
91143379 GI |
1389 | regulator_disable(ts->reg); |
1390 | regulator_put(ts->reg); | |
1391 | ||
0fbc9fdb DT |
1392 | if (!ts->get_pendown_state) { |
1393 | /* | |
1394 | * If we are not using specialized pendown method we must | |
1395 | * have been relying on gpio we set up ourselves. | |
1396 | */ | |
4d5975e5 | 1397 | gpio_free(ts->gpio_pendown); |
0fbc9fdb | 1398 | } |
4d5975e5 | 1399 | |
da970e69 ID |
1400 | if (ts->filter_cleanup) |
1401 | ts->filter_cleanup(ts->filter_data); | |
1402 | ||
e8f462d2 | 1403 | kfree(ts->packet); |
ffa458c1 DB |
1404 | kfree(ts); |
1405 | ||
2e5a7bd9 | 1406 | dev_dbg(&spi->dev, "unregistered touchscreen\n"); |
2991a1ca | 1407 | |
ffa458c1 DB |
1408 | return 0; |
1409 | } | |
1410 | ||
2e5a7bd9 DB |
1411 | static struct spi_driver ads7846_driver = { |
1412 | .driver = { | |
1413 | .name = "ads7846", | |
1414 | .bus = &spi_bus_type, | |
1415 | .owner = THIS_MODULE, | |
3c36e719 | 1416 | .pm = &ads7846_pm, |
2e5a7bd9 | 1417 | }, |
ffa458c1 | 1418 | .probe = ads7846_probe, |
2e5a7bd9 | 1419 | .remove = __devexit_p(ads7846_remove), |
ffa458c1 DB |
1420 | }; |
1421 | ||
1422 | static int __init ads7846_init(void) | |
1423 | { | |
2e5a7bd9 | 1424 | return spi_register_driver(&ads7846_driver); |
ffa458c1 DB |
1425 | } |
1426 | module_init(ads7846_init); | |
1427 | ||
1428 | static void __exit ads7846_exit(void) | |
1429 | { | |
2e5a7bd9 | 1430 | spi_unregister_driver(&ads7846_driver); |
ffa458c1 DB |
1431 | } |
1432 | module_exit(ads7846_exit); | |
1433 | ||
1434 | MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); | |
1435 | MODULE_LICENSE("GPL"); | |
e0626e38 | 1436 | MODULE_ALIAS("spi:ads7846"); |