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 | */ | |
2c8dc071 | 20 | #include <linux/hwmon.h> |
ffa458c1 | 21 | #include <linux/init.h> |
2c8dc071 | 22 | #include <linux/err.h> |
ffa458c1 DB |
23 | #include <linux/delay.h> |
24 | #include <linux/input.h> | |
25 | #include <linux/interrupt.h> | |
26 | #include <linux/slab.h> | |
4d5975e5 | 27 | #include <linux/gpio.h> |
ffa458c1 DB |
28 | #include <linux/spi/spi.h> |
29 | #include <linux/spi/ads7846.h> | |
91143379 | 30 | #include <linux/regulator/consumer.h> |
3ac8bf07 | 31 | #include <asm/irq.h> |
ffa458c1 | 32 | |
ffa458c1 | 33 | /* |
9084533e | 34 | * This code has been heavily tested on a Nokia 770, and lightly |
52ce4eaa | 35 | * tested on other ads7846 devices (OSK/Mistral, Lubbock, Spitz). |
bff0de5f | 36 | * TSC2046 is just newer ads7846 silicon. |
969111e9 NF |
37 | * Support for ads7843 tested on Atmel at91sam926x-EK. |
38 | * Support for ads7845 has only been stubbed in. | |
06a09124 | 39 | * Support for Analog Devices AD7873 and AD7843 tested. |
ffa458c1 | 40 | * |
7de90a8c ID |
41 | * IRQ handling needs a workaround because of a shortcoming in handling |
42 | * edge triggered IRQs on some platforms like the OMAP1/2. These | |
43 | * platforms don't handle the ARM lazy IRQ disabling properly, thus we | |
44 | * have to maintain our own SW IRQ disabled status. This should be | |
45 | * removed as soon as the affected platform's IRQ handling is fixed. | |
46 | * | |
52ce4eaa | 47 | * App note sbaa036 talks in more detail about accurate sampling... |
ffa458c1 DB |
48 | * that ought to help in situations like LCDs inducing noise (which |
49 | * can also be helped by using synch signals) and more generally. | |
7de90a8c ID |
50 | * This driver tries to utilize the measures described in the app |
51 | * note. The strength of filtering can be set in the board-* specific | |
52 | * files. | |
ffa458c1 DB |
53 | */ |
54 | ||
1936d590 ID |
55 | #define TS_POLL_DELAY (1 * 1000000) /* ns delay before the first sample */ |
56 | #define TS_POLL_PERIOD (5 * 1000000) /* ns delay between samples */ | |
ffa458c1 | 57 | |
d93f70b2 DB |
58 | /* this driver doesn't aim at the peak continuous sample rate */ |
59 | #define SAMPLE_BITS (8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */) | |
60 | ||
ffa458c1 DB |
61 | struct ts_event { |
62 | /* For portability, we can't read 12 bit values using SPI (which | |
63 | * would make the controller deliver them as native byteorder u16 | |
d93f70b2 | 64 | * with msbs zeroed). Instead, we read them as two 8-bit values, |
da970e69 | 65 | * *** WHICH NEED BYTESWAPPING *** and range adjustment. |
ffa458c1 | 66 | */ |
da970e69 ID |
67 | u16 x; |
68 | u16 y; | |
69 | u16 z1, z2; | |
2c8dc071 | 70 | int ignore; |
ffa458c1 DB |
71 | }; |
72 | ||
e8f462d2 DT |
73 | /* |
74 | * We allocate this separately to avoid cache line sharing issues when | |
75 | * driver is used with DMA-based SPI controllers (like atmel_spi) on | |
76 | * systems where main memory is not DMA-coherent (most non-x86 boards). | |
77 | */ | |
78 | struct ads7846_packet { | |
79 | u8 read_x, read_y, read_z1, read_z2, pwrdown; | |
80 | u16 dummy; /* for the pwrdown read */ | |
81 | struct ts_event tc; | |
82 | }; | |
83 | ||
ffa458c1 | 84 | struct ads7846 { |
a90f7e98 | 85 | struct input_dev *input; |
ffa458c1 | 86 | char phys[32]; |
b58895f8 | 87 | char name[32]; |
ffa458c1 DB |
88 | |
89 | struct spi_device *spi; | |
91143379 | 90 | struct regulator *reg; |
2c8dc071 DB |
91 | |
92 | #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) | |
8dd51650 | 93 | struct attribute_group *attr_group; |
1beeffe4 | 94 | struct device *hwmon; |
2c8dc071 DB |
95 | #endif |
96 | ||
ffa458c1 | 97 | u16 model; |
7c6d0ee1 | 98 | u16 vref_mv; |
ffa458c1 DB |
99 | u16 vref_delay_usecs; |
100 | u16 x_plate_ohms; | |
d5b415c9 | 101 | u16 pressure_max; |
ffa458c1 | 102 | |
86579a4c MR |
103 | bool swap_xy; |
104 | ||
e8f462d2 | 105 | struct ads7846_packet *packet; |
ffa458c1 | 106 | |
e4f48861 | 107 | struct spi_transfer xfer[18]; |
0b7018aa | 108 | struct spi_message msg[5]; |
d5b415c9 | 109 | struct spi_message *last_msg; |
0b7018aa ID |
110 | int msg_idx; |
111 | int read_cnt; | |
d5b415c9 | 112 | int read_rep; |
0b7018aa ID |
113 | int last_read; |
114 | ||
115 | u16 debounce_max; | |
116 | u16 debounce_tol; | |
d5b415c9 | 117 | u16 debounce_rep; |
ffa458c1 | 118 | |
1d25891f SH |
119 | u16 penirq_recheck_delay_usecs; |
120 | ||
ffa458c1 | 121 | spinlock_t lock; |
1936d590 | 122 | struct hrtimer timer; |
ffa458c1 DB |
123 | unsigned pendown:1; /* P: lock */ |
124 | unsigned pending:1; /* P: lock */ | |
125 | // FIXME remove "irq_disabled" | |
126 | unsigned irq_disabled:1; /* P: lock */ | |
7de90a8c | 127 | unsigned disabled:1; |
fbb38e30 | 128 | unsigned is_suspended:1; |
c9e617a5 | 129 | |
da970e69 ID |
130 | int (*filter)(void *data, int data_idx, int *val); |
131 | void *filter_data; | |
132 | void (*filter_cleanup)(void *data); | |
c9e617a5 | 133 | int (*get_pendown_state)(void); |
4d5975e5 | 134 | int gpio_pendown; |
fd746d54 EM |
135 | |
136 | void (*wait_for_sync)(void); | |
ffa458c1 DB |
137 | }; |
138 | ||
139 | /* leave chip selected when we're done, for quicker re-select? */ | |
140 | #if 0 | |
141 | #define CS_CHANGE(xfer) ((xfer).cs_change = 1) | |
142 | #else | |
143 | #define CS_CHANGE(xfer) ((xfer).cs_change = 0) | |
144 | #endif | |
145 | ||
146 | /*--------------------------------------------------------------------------*/ | |
147 | ||
148 | /* The ADS7846 has touchscreen and other sensors. | |
149 | * Earlier ads784x chips are somewhat compatible. | |
150 | */ | |
151 | #define ADS_START (1 << 7) | |
152 | #define ADS_A2A1A0_d_y (1 << 4) /* differential */ | |
153 | #define ADS_A2A1A0_d_z1 (3 << 4) /* differential */ | |
154 | #define ADS_A2A1A0_d_z2 (4 << 4) /* differential */ | |
155 | #define ADS_A2A1A0_d_x (5 << 4) /* differential */ | |
156 | #define ADS_A2A1A0_temp0 (0 << 4) /* non-differential */ | |
157 | #define ADS_A2A1A0_vbatt (2 << 4) /* non-differential */ | |
158 | #define ADS_A2A1A0_vaux (6 << 4) /* non-differential */ | |
159 | #define ADS_A2A1A0_temp1 (7 << 4) /* non-differential */ | |
160 | #define ADS_8_BIT (1 << 3) | |
161 | #define ADS_12_BIT (0 << 3) | |
162 | #define ADS_SER (1 << 2) /* non-differential */ | |
163 | #define ADS_DFR (0 << 2) /* differential */ | |
164 | #define ADS_PD10_PDOWN (0 << 0) /* lowpower mode + penirq */ | |
165 | #define ADS_PD10_ADC_ON (1 << 0) /* ADC on */ | |
166 | #define ADS_PD10_REF_ON (2 << 0) /* vREF on + penirq */ | |
167 | #define ADS_PD10_ALL_ON (3 << 0) /* ADC + vREF on */ | |
168 | ||
169 | #define MAX_12BIT ((1<<12)-1) | |
170 | ||
171 | /* leave ADC powered up (disables penirq) between differential samples */ | |
de2defd9 ID |
172 | #define READ_12BIT_DFR(x, adc, vref) (ADS_START | ADS_A2A1A0_d_ ## x \ |
173 | | ADS_12_BIT | ADS_DFR | \ | |
174 | (adc ? ADS_PD10_ADC_ON : 0) | (vref ? ADS_PD10_REF_ON : 0)) | |
ffa458c1 | 175 | |
de2defd9 ID |
176 | #define READ_Y(vref) (READ_12BIT_DFR(y, 1, vref)) |
177 | #define READ_Z1(vref) (READ_12BIT_DFR(z1, 1, vref)) | |
178 | #define READ_Z2(vref) (READ_12BIT_DFR(z2, 1, vref)) | |
53a0ef89 | 179 | |
de2defd9 ID |
180 | #define READ_X(vref) (READ_12BIT_DFR(x, 1, vref)) |
181 | #define PWRDOWN (READ_12BIT_DFR(y, 0, 0)) /* LAST */ | |
ffa458c1 DB |
182 | |
183 | /* single-ended samples need to first power up reference voltage; | |
184 | * we leave both ADC and VREF powered | |
185 | */ | |
186 | #define READ_12BIT_SER(x) (ADS_START | ADS_A2A1A0_ ## x \ | |
187 | | ADS_12_BIT | ADS_SER) | |
188 | ||
de2defd9 ID |
189 | #define REF_ON (READ_12BIT_DFR(x, 1, 1)) |
190 | #define REF_OFF (READ_12BIT_DFR(y, 0, 0)) | |
ffa458c1 DB |
191 | |
192 | /*--------------------------------------------------------------------------*/ | |
193 | ||
194 | /* | |
195 | * Non-touchscreen sensors only use single-ended conversions. | |
2c8dc071 DB |
196 | * The range is GND..vREF. The ads7843 and ads7835 must use external vREF; |
197 | * ads7846 lets that pin be unconnected, to use internal vREF. | |
ffa458c1 DB |
198 | */ |
199 | ||
200 | struct ser_req { | |
d93f70b2 | 201 | u8 ref_on; |
ffa458c1 | 202 | u8 command; |
d93f70b2 | 203 | u8 ref_off; |
ffa458c1 DB |
204 | u16 scratch; |
205 | __be16 sample; | |
206 | struct spi_message msg; | |
207 | struct spi_transfer xfer[6]; | |
208 | }; | |
209 | ||
7de90a8c ID |
210 | static void ads7846_enable(struct ads7846 *ts); |
211 | static void ads7846_disable(struct ads7846 *ts); | |
212 | ||
c9e617a5 ID |
213 | static int device_suspended(struct device *dev) |
214 | { | |
215 | struct ads7846 *ts = dev_get_drvdata(dev); | |
fbb38e30 | 216 | return ts->is_suspended || ts->disabled; |
c9e617a5 ID |
217 | } |
218 | ||
ffa458c1 DB |
219 | static int ads7846_read12_ser(struct device *dev, unsigned command) |
220 | { | |
221 | struct spi_device *spi = to_spi_device(dev); | |
222 | struct ads7846 *ts = dev_get_drvdata(dev); | |
e94b1766 | 223 | struct ser_req *req = kzalloc(sizeof *req, GFP_KERNEL); |
ffa458c1 | 224 | int status; |
2c8dc071 | 225 | int use_internal; |
ffa458c1 DB |
226 | |
227 | if (!req) | |
228 | return -ENOMEM; | |
229 | ||
0b7018aa | 230 | spi_message_init(&req->msg); |
8275c642 | 231 | |
2c8dc071 DB |
232 | /* FIXME boards with ads7846 might use external vref instead ... */ |
233 | use_internal = (ts->model == 7846); | |
234 | ||
235 | /* maybe turn on internal vREF, and let it settle */ | |
236 | if (use_internal) { | |
237 | req->ref_on = REF_ON; | |
238 | req->xfer[0].tx_buf = &req->ref_on; | |
239 | req->xfer[0].len = 1; | |
240 | spi_message_add_tail(&req->xfer[0], &req->msg); | |
241 | ||
242 | req->xfer[1].rx_buf = &req->scratch; | |
243 | req->xfer[1].len = 2; | |
244 | ||
245 | /* for 1uF, settle for 800 usec; no cap, 100 usec. */ | |
246 | req->xfer[1].delay_usecs = ts->vref_delay_usecs; | |
247 | spi_message_add_tail(&req->xfer[1], &req->msg); | |
248 | } | |
ffa458c1 DB |
249 | |
250 | /* take sample */ | |
251 | req->command = (u8) command; | |
252 | req->xfer[2].tx_buf = &req->command; | |
253 | req->xfer[2].len = 1; | |
2c8dc071 DB |
254 | spi_message_add_tail(&req->xfer[2], &req->msg); |
255 | ||
ffa458c1 DB |
256 | req->xfer[3].rx_buf = &req->sample; |
257 | req->xfer[3].len = 2; | |
2c8dc071 | 258 | spi_message_add_tail(&req->xfer[3], &req->msg); |
ffa458c1 DB |
259 | |
260 | /* REVISIT: take a few more samples, and compare ... */ | |
261 | ||
969111e9 NF |
262 | /* converter in low power mode & enable PENIRQ */ |
263 | req->ref_off = PWRDOWN; | |
264 | req->xfer[4].tx_buf = &req->ref_off; | |
265 | req->xfer[4].len = 1; | |
266 | spi_message_add_tail(&req->xfer[4], &req->msg); | |
267 | ||
268 | req->xfer[5].rx_buf = &req->scratch; | |
269 | req->xfer[5].len = 2; | |
270 | CS_CHANGE(req->xfer[5]); | |
271 | spi_message_add_tail(&req->xfer[5], &req->msg); | |
ffa458c1 | 272 | |
c9e617a5 | 273 | ts->irq_disabled = 1; |
ffa458c1 DB |
274 | disable_irq(spi->irq); |
275 | status = spi_sync(spi, &req->msg); | |
c9e617a5 | 276 | ts->irq_disabled = 0; |
ffa458c1 DB |
277 | enable_irq(spi->irq); |
278 | ||
c24b2602 MP |
279 | if (status == 0) { |
280 | /* on-wire is a must-ignore bit, a BE12 value, then padding */ | |
7c6d0ee1 DB |
281 | status = be16_to_cpu(req->sample); |
282 | status = status >> 3; | |
283 | status &= 0x0fff; | |
c24b2602 | 284 | } |
ffa458c1 | 285 | |
9084533e | 286 | kfree(req); |
7c6d0ee1 | 287 | return status; |
ffa458c1 DB |
288 | } |
289 | ||
2c8dc071 DB |
290 | #if defined(CONFIG_HWMON) || defined(CONFIG_HWMON_MODULE) |
291 | ||
292 | #define SHOW(name, var, adjust) static ssize_t \ | |
ffa458c1 DB |
293 | name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \ |
294 | { \ | |
2c8dc071 | 295 | struct ads7846 *ts = dev_get_drvdata(dev); \ |
ffa458c1 | 296 | ssize_t v = ads7846_read12_ser(dev, \ |
2c8dc071 | 297 | READ_12BIT_SER(var) | ADS_PD10_ALL_ON); \ |
ffa458c1 DB |
298 | if (v < 0) \ |
299 | return v; \ | |
2c8dc071 | 300 | return sprintf(buf, "%u\n", adjust(ts, v)); \ |
ffa458c1 DB |
301 | } \ |
302 | static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL); | |
303 | ||
2c8dc071 | 304 | |
b731d7b6 | 305 | /* Sysfs conventions report temperatures in millidegrees Celsius. |
2c8dc071 DB |
306 | * ADS7846 could use the low-accuracy two-sample scheme, but can't do the high |
307 | * accuracy scheme without calibration data. For now we won't try either; | |
308 | * userspace sees raw sensor values, and must scale/calibrate appropriately. | |
309 | */ | |
310 | static inline unsigned null_adjust(struct ads7846 *ts, ssize_t v) | |
311 | { | |
312 | return v; | |
313 | } | |
314 | ||
315 | SHOW(temp0, temp0, null_adjust) /* temp1_input */ | |
316 | SHOW(temp1, temp1, null_adjust) /* temp2_input */ | |
317 | ||
318 | ||
319 | /* sysfs conventions report voltages in millivolts. We can convert voltages | |
320 | * if we know vREF. userspace may need to scale vAUX to match the board's | |
321 | * external resistors; we assume that vBATT only uses the internal ones. | |
322 | */ | |
323 | static inline unsigned vaux_adjust(struct ads7846 *ts, ssize_t v) | |
324 | { | |
325 | unsigned retval = v; | |
326 | ||
327 | /* external resistors may scale vAUX into 0..vREF */ | |
7c6d0ee1 | 328 | retval *= ts->vref_mv; |
2c8dc071 DB |
329 | retval = retval >> 12; |
330 | return retval; | |
331 | } | |
332 | ||
333 | static inline unsigned vbatt_adjust(struct ads7846 *ts, ssize_t v) | |
334 | { | |
335 | unsigned retval = vaux_adjust(ts, v); | |
336 | ||
337 | /* ads7846 has a resistor ladder to scale this signal down */ | |
338 | if (ts->model == 7846) | |
339 | retval *= 4; | |
340 | return retval; | |
341 | } | |
342 | ||
343 | SHOW(in0_input, vaux, vaux_adjust) | |
344 | SHOW(in1_input, vbatt, vbatt_adjust) | |
345 | ||
346 | ||
347 | static struct attribute *ads7846_attributes[] = { | |
348 | &dev_attr_temp0.attr, | |
349 | &dev_attr_temp1.attr, | |
350 | &dev_attr_in0_input.attr, | |
351 | &dev_attr_in1_input.attr, | |
352 | NULL, | |
353 | }; | |
354 | ||
355 | static struct attribute_group ads7846_attr_group = { | |
356 | .attrs = ads7846_attributes, | |
357 | }; | |
358 | ||
359 | static struct attribute *ads7843_attributes[] = { | |
360 | &dev_attr_in0_input.attr, | |
361 | &dev_attr_in1_input.attr, | |
362 | NULL, | |
363 | }; | |
364 | ||
365 | static struct attribute_group ads7843_attr_group = { | |
366 | .attrs = ads7843_attributes, | |
367 | }; | |
368 | ||
369 | static struct attribute *ads7845_attributes[] = { | |
370 | &dev_attr_in0_input.attr, | |
371 | NULL, | |
372 | }; | |
373 | ||
374 | static struct attribute_group ads7845_attr_group = { | |
375 | .attrs = ads7845_attributes, | |
376 | }; | |
377 | ||
378 | static int ads784x_hwmon_register(struct spi_device *spi, struct ads7846 *ts) | |
379 | { | |
1beeffe4 | 380 | struct device *hwmon; |
2c8dc071 DB |
381 | int err; |
382 | ||
383 | /* hwmon sensors need a reference voltage */ | |
384 | switch (ts->model) { | |
385 | case 7846: | |
7c6d0ee1 | 386 | if (!ts->vref_mv) { |
2c8dc071 | 387 | dev_dbg(&spi->dev, "assuming 2.5V internal vREF\n"); |
7c6d0ee1 | 388 | ts->vref_mv = 2500; |
2c8dc071 DB |
389 | } |
390 | break; | |
391 | case 7845: | |
392 | case 7843: | |
7c6d0ee1 | 393 | if (!ts->vref_mv) { |
2c8dc071 DB |
394 | dev_warn(&spi->dev, |
395 | "external vREF for ADS%d not specified\n", | |
396 | ts->model); | |
397 | return 0; | |
398 | } | |
399 | break; | |
400 | } | |
401 | ||
402 | /* different chips have different sensor groups */ | |
403 | switch (ts->model) { | |
404 | case 7846: | |
405 | ts->attr_group = &ads7846_attr_group; | |
406 | break; | |
407 | case 7845: | |
408 | ts->attr_group = &ads7845_attr_group; | |
409 | break; | |
410 | case 7843: | |
411 | ts->attr_group = &ads7843_attr_group; | |
412 | break; | |
413 | default: | |
414 | dev_dbg(&spi->dev, "ADS%d not recognized\n", ts->model); | |
415 | return 0; | |
416 | } | |
417 | ||
418 | err = sysfs_create_group(&spi->dev.kobj, ts->attr_group); | |
419 | if (err) | |
420 | return err; | |
421 | ||
422 | hwmon = hwmon_device_register(&spi->dev); | |
423 | if (IS_ERR(hwmon)) { | |
424 | sysfs_remove_group(&spi->dev.kobj, ts->attr_group); | |
425 | return PTR_ERR(hwmon); | |
426 | } | |
427 | ||
428 | ts->hwmon = hwmon; | |
429 | return 0; | |
430 | } | |
431 | ||
432 | static void ads784x_hwmon_unregister(struct spi_device *spi, | |
433 | struct ads7846 *ts) | |
434 | { | |
435 | if (ts->hwmon) { | |
436 | sysfs_remove_group(&spi->dev.kobj, ts->attr_group); | |
437 | hwmon_device_unregister(ts->hwmon); | |
438 | } | |
439 | } | |
440 | ||
441 | #else | |
442 | static inline int ads784x_hwmon_register(struct spi_device *spi, | |
443 | struct ads7846 *ts) | |
444 | { | |
445 | return 0; | |
446 | } | |
447 | ||
448 | static inline void ads784x_hwmon_unregister(struct spi_device *spi, | |
449 | struct ads7846 *ts) | |
450 | { | |
451 | } | |
452 | #endif | |
ffa458c1 | 453 | |
438f2a74 ID |
454 | static int is_pen_down(struct device *dev) |
455 | { | |
2c8dc071 | 456 | struct ads7846 *ts = dev_get_drvdata(dev); |
438f2a74 ID |
457 | |
458 | return ts->pendown; | |
459 | } | |
460 | ||
461 | static ssize_t ads7846_pen_down_show(struct device *dev, | |
462 | struct device_attribute *attr, char *buf) | |
463 | { | |
464 | return sprintf(buf, "%u\n", is_pen_down(dev)); | |
465 | } | |
466 | ||
467 | static DEVICE_ATTR(pen_down, S_IRUGO, ads7846_pen_down_show, NULL); | |
468 | ||
7de90a8c ID |
469 | static ssize_t ads7846_disable_show(struct device *dev, |
470 | struct device_attribute *attr, char *buf) | |
471 | { | |
472 | struct ads7846 *ts = dev_get_drvdata(dev); | |
473 | ||
474 | return sprintf(buf, "%u\n", ts->disabled); | |
475 | } | |
476 | ||
477 | static ssize_t ads7846_disable_store(struct device *dev, | |
478 | struct device_attribute *attr, | |
479 | const char *buf, size_t count) | |
480 | { | |
481 | struct ads7846 *ts = dev_get_drvdata(dev); | |
3a0c58dd | 482 | unsigned long i; |
160f1fef JR |
483 | |
484 | if (strict_strtoul(buf, 10, &i)) | |
485 | return -EINVAL; | |
7de90a8c | 486 | |
7de90a8c ID |
487 | spin_lock_irq(&ts->lock); |
488 | ||
489 | if (i) | |
490 | ads7846_disable(ts); | |
491 | else | |
492 | ads7846_enable(ts); | |
493 | ||
494 | spin_unlock_irq(&ts->lock); | |
495 | ||
496 | return count; | |
497 | } | |
498 | ||
499 | static DEVICE_ATTR(disable, 0664, ads7846_disable_show, ads7846_disable_store); | |
500 | ||
2c8dc071 | 501 | static struct attribute *ads784x_attributes[] = { |
8dd51650 DT |
502 | &dev_attr_pen_down.attr, |
503 | &dev_attr_disable.attr, | |
504 | NULL, | |
505 | }; | |
506 | ||
2c8dc071 DB |
507 | static struct attribute_group ads784x_attr_group = { |
508 | .attrs = ads784x_attributes, | |
8dd51650 DT |
509 | }; |
510 | ||
ffa458c1 DB |
511 | /*--------------------------------------------------------------------------*/ |
512 | ||
4d5975e5 EM |
513 | static int get_pendown_state(struct ads7846 *ts) |
514 | { | |
515 | if (ts->get_pendown_state) | |
516 | return ts->get_pendown_state(); | |
517 | ||
518 | return !gpio_get_value(ts->gpio_pendown); | |
519 | } | |
520 | ||
fd746d54 EM |
521 | static void null_wait_for_sync(void) |
522 | { | |
523 | } | |
524 | ||
ffa458c1 DB |
525 | /* |
526 | * PENIRQ only kicks the timer. The timer only reissues the SPI transfer, | |
527 | * to retrieve touchscreen status. | |
528 | * | |
529 | * The SPI transfer completion callback does the real work. It reports | |
530 | * touchscreen events and reactivates the timer (or IRQ) as appropriate. | |
531 | */ | |
532 | ||
533 | static void ads7846_rx(void *ads) | |
534 | { | |
a90f7e98 | 535 | struct ads7846 *ts = ads; |
e8f462d2 | 536 | struct ads7846_packet *packet = ts->packet; |
a90f7e98 | 537 | unsigned Rt; |
a90f7e98 | 538 | u16 x, y, z1, z2; |
ffa458c1 | 539 | |
da970e69 ID |
540 | /* ads7846_rx_val() did in-place conversion (including byteswap) from |
541 | * on-the-wire format as part of debouncing to get stable readings. | |
ffa458c1 | 542 | */ |
e8f462d2 DT |
543 | x = packet->tc.x; |
544 | y = packet->tc.y; | |
545 | z1 = packet->tc.z1; | |
546 | z2 = packet->tc.z2; | |
ffa458c1 DB |
547 | |
548 | /* range filtering */ | |
549 | if (x == MAX_12BIT) | |
550 | x = 0; | |
551 | ||
9460b652 HCE |
552 | if (ts->model == 7843) { |
553 | Rt = ts->pressure_max / 2; | |
554 | } else if (likely(x && z1)) { | |
ffa458c1 DB |
555 | /* compute touch pressure resistance using equation #2 */ |
556 | Rt = z2; | |
557 | Rt -= z1; | |
558 | Rt *= x; | |
559 | Rt *= ts->x_plate_ohms; | |
560 | Rt /= z1; | |
561 | Rt = (Rt + 2047) >> 12; | |
9460b652 | 562 | } else { |
ffa458c1 | 563 | Rt = 0; |
9460b652 | 564 | } |
969111e9 | 565 | |
d5b415c9 | 566 | /* Sample found inconsistent by debouncing or pressure is beyond |
1936d590 ID |
567 | * the maximum. Don't report it to user space, repeat at least |
568 | * once more the measurement | |
569 | */ | |
e8f462d2 | 570 | if (packet->tc.ignore || Rt > ts->pressure_max) { |
52ce4eaa PM |
571 | dev_vdbg(&ts->spi->dev, "ignored %d pressure %d\n", |
572 | packet->tc.ignore, Rt); | |
1936d590 | 573 | hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), |
c9cb2e3d | 574 | HRTIMER_MODE_REL); |
d5b415c9 ID |
575 | return; |
576 | } | |
577 | ||
1d25891f SH |
578 | /* Maybe check the pendown state before reporting. This discards |
579 | * false readings when the pen is lifted. | |
580 | */ | |
581 | if (ts->penirq_recheck_delay_usecs) { | |
582 | udelay(ts->penirq_recheck_delay_usecs); | |
4d5975e5 | 583 | if (!get_pendown_state(ts)) |
1d25891f SH |
584 | Rt = 0; |
585 | } | |
586 | ||
15e3589e ID |
587 | /* NOTE: We can't rely on the pressure to determine the pen down |
588 | * state, even this controller has a pressure sensor. The pressure | |
589 | * value can fluctuate for quite a while after lifting the pen and | |
590 | * in some cases may not even settle at the expected value. | |
ffa458c1 | 591 | * |
15e3589e ID |
592 | * The only safe way to check for the pen up condition is in the |
593 | * timer by reading the pen signal state (it's a GPIO _and_ IRQ). | |
ffa458c1 | 594 | */ |
ffa458c1 | 595 | if (Rt) { |
15e3589e | 596 | struct input_dev *input = ts->input; |
ae82d5ab | 597 | |
15e3589e ID |
598 | if (!ts->pendown) { |
599 | input_report_key(input, BTN_TOUCH, 1); | |
600 | ts->pendown = 1; | |
52ce4eaa | 601 | dev_vdbg(&ts->spi->dev, "DOWN\n"); |
15e3589e | 602 | } |
86579a4c MR |
603 | |
604 | if (ts->swap_xy) | |
605 | swap(x, y); | |
606 | ||
15e3589e ID |
607 | input_report_abs(input, ABS_X, x); |
608 | input_report_abs(input, ABS_Y, y); | |
30ad7ba0 | 609 | input_report_abs(input, ABS_PRESSURE, ts->pressure_max - Rt); |
ffa458c1 | 610 | |
15e3589e | 611 | input_sync(input); |
52ce4eaa | 612 | dev_vdbg(&ts->spi->dev, "%4d/%4d/%4d\n", x, y, Rt); |
15e3589e | 613 | } |
ffa458c1 | 614 | |
c9cb2e3d TG |
615 | hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), |
616 | HRTIMER_MODE_REL); | |
ffa458c1 DB |
617 | } |
618 | ||
da970e69 | 619 | static int ads7846_debounce(void *ads, int data_idx, int *val) |
0b7018aa ID |
620 | { |
621 | struct ads7846 *ts = ads; | |
0b7018aa | 622 | |
da970e69 ID |
623 | if (!ts->read_cnt || (abs(ts->last_read - *val) > ts->debounce_tol)) { |
624 | /* Start over collecting consistent readings. */ | |
625 | ts->read_rep = 0; | |
d5b415c9 ID |
626 | /* Repeat it, if this was the first read or the read |
627 | * wasn't consistent enough. */ | |
628 | if (ts->read_cnt < ts->debounce_max) { | |
da970e69 | 629 | ts->last_read = *val; |
d5b415c9 | 630 | ts->read_cnt++; |
da970e69 | 631 | return ADS7846_FILTER_REPEAT; |
d5b415c9 ID |
632 | } else { |
633 | /* Maximum number of debouncing reached and still | |
634 | * not enough number of consistent readings. Abort | |
635 | * the whole sample, repeat it in the next sampling | |
636 | * period. | |
637 | */ | |
d5b415c9 | 638 | ts->read_cnt = 0; |
da970e69 | 639 | return ADS7846_FILTER_IGNORE; |
d5b415c9 | 640 | } |
0b7018aa | 641 | } else { |
d5b415c9 ID |
642 | if (++ts->read_rep > ts->debounce_rep) { |
643 | /* Got a good reading for this coordinate, | |
644 | * go for the next one. */ | |
d5b415c9 ID |
645 | ts->read_cnt = 0; |
646 | ts->read_rep = 0; | |
da970e69 ID |
647 | return ADS7846_FILTER_OK; |
648 | } else { | |
d5b415c9 ID |
649 | /* Read more values that are consistent. */ |
650 | ts->read_cnt++; | |
da970e69 ID |
651 | return ADS7846_FILTER_REPEAT; |
652 | } | |
653 | } | |
654 | } | |
655 | ||
656 | static int ads7846_no_filter(void *ads, int data_idx, int *val) | |
657 | { | |
658 | return ADS7846_FILTER_OK; | |
659 | } | |
660 | ||
661 | static void ads7846_rx_val(void *ads) | |
662 | { | |
663 | struct ads7846 *ts = ads; | |
e8f462d2 | 664 | struct ads7846_packet *packet = ts->packet; |
da970e69 ID |
665 | struct spi_message *m; |
666 | struct spi_transfer *t; | |
da970e69 ID |
667 | int val; |
668 | int action; | |
669 | int status; | |
670 | ||
671 | m = &ts->msg[ts->msg_idx]; | |
672 | t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list); | |
da970e69 ID |
673 | |
674 | /* adjust: on-wire is a must-ignore bit, a BE12 value, then padding; | |
675 | * built from two 8 bit values written msb-first. | |
676 | */ | |
494f6857 | 677 | val = be16_to_cpup((__be16 *)t->rx_buf) >> 3; |
da970e69 ID |
678 | |
679 | action = ts->filter(ts->filter_data, ts->msg_idx, &val); | |
680 | switch (action) { | |
681 | case ADS7846_FILTER_REPEAT: | |
682 | break; | |
683 | case ADS7846_FILTER_IGNORE: | |
e8f462d2 | 684 | packet->tc.ignore = 1; |
da970e69 ID |
685 | /* Last message will contain ads7846_rx() as the |
686 | * completion function. | |
687 | */ | |
688 | m = ts->last_msg; | |
689 | break; | |
690 | case ADS7846_FILTER_OK: | |
494f6857 | 691 | *(u16 *)t->rx_buf = val; |
e8f462d2 | 692 | packet->tc.ignore = 0; |
da970e69 ID |
693 | m = &ts->msg[++ts->msg_idx]; |
694 | break; | |
695 | default: | |
696 | BUG(); | |
0b7018aa | 697 | } |
fd746d54 | 698 | ts->wait_for_sync(); |
0b7018aa ID |
699 | status = spi_async(ts->spi, m); |
700 | if (status) | |
701 | dev_err(&ts->spi->dev, "spi_async --> %d\n", | |
702 | status); | |
703 | } | |
704 | ||
c9cb2e3d | 705 | static enum hrtimer_restart ads7846_timer(struct hrtimer *handle) |
ffa458c1 | 706 | { |
1936d590 | 707 | struct ads7846 *ts = container_of(handle, struct ads7846, timer); |
ffa458c1 | 708 | int status = 0; |
0b7018aa | 709 | |
ca109491 | 710 | spin_lock(&ts->lock); |
c9e617a5 | 711 | |
4d5975e5 | 712 | if (unlikely(!get_pendown_state(ts) || |
15e3589e ID |
713 | device_suspended(&ts->spi->dev))) { |
714 | if (ts->pendown) { | |
715 | struct input_dev *input = ts->input; | |
716 | ||
717 | input_report_key(input, BTN_TOUCH, 0); | |
718 | input_report_abs(input, ABS_PRESSURE, 0); | |
719 | input_sync(input); | |
720 | ||
721 | ts->pendown = 0; | |
52ce4eaa | 722 | dev_vdbg(&ts->spi->dev, "UP\n"); |
15e3589e ID |
723 | } |
724 | ||
9084533e | 725 | /* measurement cycle ended */ |
c9e617a5 ID |
726 | if (!device_suspended(&ts->spi->dev)) { |
727 | ts->irq_disabled = 0; | |
728 | enable_irq(ts->spi->irq); | |
729 | } | |
730 | ts->pending = 0; | |
c9e617a5 ID |
731 | } else { |
732 | /* pen is still down, continue with the measurement */ | |
733 | ts->msg_idx = 0; | |
fd746d54 | 734 | ts->wait_for_sync(); |
c9e617a5 ID |
735 | status = spi_async(ts->spi, &ts->msg[0]); |
736 | if (status) | |
737 | dev_err(&ts->spi->dev, "spi_async --> %d\n", status); | |
738 | } | |
739 | ||
ca109491 | 740 | spin_unlock(&ts->lock); |
1936d590 | 741 | return HRTIMER_NORESTART; |
0b7018aa ID |
742 | } |
743 | ||
7d12e780 | 744 | static irqreturn_t ads7846_irq(int irq, void *handle) |
0b7018aa ID |
745 | { |
746 | struct ads7846 *ts = handle; | |
747 | unsigned long flags; | |
ffa458c1 DB |
748 | |
749 | spin_lock_irqsave(&ts->lock, flags); | |
4d5975e5 | 750 | if (likely(get_pendown_state(ts))) { |
ffa458c1 | 751 | if (!ts->irq_disabled) { |
9084533e DB |
752 | /* The ARM do_simple_IRQ() dispatcher doesn't act |
753 | * like the other dispatchers: it will report IRQs | |
754 | * even after they've been disabled. We work around | |
755 | * that here. (The "generic irq" framework may help...) | |
0b7018aa | 756 | */ |
ffa458c1 | 757 | ts->irq_disabled = 1; |
3f3e7c6e | 758 | disable_irq_nosync(ts->spi->irq); |
0b7018aa | 759 | ts->pending = 1; |
1936d590 | 760 | hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY), |
c9cb2e3d | 761 | HRTIMER_MODE_REL); |
0b7018aa | 762 | } |
ffa458c1 DB |
763 | } |
764 | spin_unlock_irqrestore(&ts->lock, flags); | |
7de90a8c ID |
765 | |
766 | return IRQ_HANDLED; | |
ffa458c1 DB |
767 | } |
768 | ||
769 | /*--------------------------------------------------------------------------*/ | |
770 | ||
7de90a8c ID |
771 | /* Must be called with ts->lock held */ |
772 | static void ads7846_disable(struct ads7846 *ts) | |
ffa458c1 | 773 | { |
7de90a8c ID |
774 | if (ts->disabled) |
775 | return; | |
ffa458c1 | 776 | |
c9e617a5 ID |
777 | ts->disabled = 1; |
778 | ||
ffa458c1 | 779 | /* are we waiting for IRQ, or polling? */ |
c9e617a5 ID |
780 | if (!ts->pending) { |
781 | ts->irq_disabled = 1; | |
782 | disable_irq(ts->spi->irq); | |
ffa458c1 | 783 | } else { |
c9e617a5 ID |
784 | /* the timer will run at least once more, and |
785 | * leave everything in a clean state, IRQ disabled | |
ffa458c1 | 786 | */ |
c9e617a5 | 787 | while (ts->pending) { |
7de90a8c | 788 | spin_unlock_irq(&ts->lock); |
c4febb94 | 789 | msleep(1); |
7de90a8c | 790 | spin_lock_irq(&ts->lock); |
ffa458c1 DB |
791 | } |
792 | } | |
793 | ||
91143379 GI |
794 | regulator_disable(ts->reg); |
795 | ||
ffa458c1 DB |
796 | /* we know the chip's in lowpower mode since we always |
797 | * leave it that way after every request | |
798 | */ | |
7de90a8c ID |
799 | } |
800 | ||
801 | /* Must be called with ts->lock held */ | |
802 | static void ads7846_enable(struct ads7846 *ts) | |
803 | { | |
804 | if (!ts->disabled) | |
805 | return; | |
806 | ||
91143379 GI |
807 | regulator_enable(ts->reg); |
808 | ||
7de90a8c ID |
809 | ts->disabled = 0; |
810 | ts->irq_disabled = 0; | |
811 | enable_irq(ts->spi->irq); | |
812 | } | |
813 | ||
814 | static int ads7846_suspend(struct spi_device *spi, pm_message_t message) | |
815 | { | |
816 | struct ads7846 *ts = dev_get_drvdata(&spi->dev); | |
817 | ||
818 | spin_lock_irq(&ts->lock); | |
819 | ||
fbb38e30 | 820 | ts->is_suspended = 1; |
7de90a8c ID |
821 | ads7846_disable(ts); |
822 | ||
823 | spin_unlock_irq(&ts->lock); | |
824 | ||
fdba2bb1 RL |
825 | if (device_may_wakeup(&ts->spi->dev)) |
826 | enable_irq_wake(ts->spi->irq); | |
827 | ||
ffa458c1 | 828 | return 0; |
7de90a8c | 829 | |
ffa458c1 DB |
830 | } |
831 | ||
2e5a7bd9 | 832 | static int ads7846_resume(struct spi_device *spi) |
ffa458c1 | 833 | { |
2e5a7bd9 | 834 | struct ads7846 *ts = dev_get_drvdata(&spi->dev); |
ffa458c1 | 835 | |
fdba2bb1 RL |
836 | if (device_may_wakeup(&ts->spi->dev)) |
837 | disable_irq_wake(ts->spi->irq); | |
838 | ||
7de90a8c ID |
839 | spin_lock_irq(&ts->lock); |
840 | ||
fbb38e30 | 841 | ts->is_suspended = 0; |
7de90a8c ID |
842 | ads7846_enable(ts); |
843 | ||
844 | spin_unlock_irq(&ts->lock); | |
845 | ||
ffa458c1 DB |
846 | return 0; |
847 | } | |
848 | ||
4d5975e5 EM |
849 | static int __devinit setup_pendown(struct spi_device *spi, struct ads7846 *ts) |
850 | { | |
851 | struct ads7846_platform_data *pdata = spi->dev.platform_data; | |
852 | int err; | |
853 | ||
854 | /* REVISIT when the irq can be triggered active-low, or if for some | |
855 | * reason the touchscreen isn't hooked up, we don't need to access | |
856 | * the pendown state. | |
857 | */ | |
858 | if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) { | |
859 | dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n"); | |
860 | return -EINVAL; | |
861 | } | |
862 | ||
863 | if (pdata->get_pendown_state) { | |
864 | ts->get_pendown_state = pdata->get_pendown_state; | |
865 | return 0; | |
866 | } | |
867 | ||
868 | err = gpio_request(pdata->gpio_pendown, "ads7846_pendown"); | |
869 | if (err) { | |
870 | dev_err(&spi->dev, "failed to request pendown GPIO%d\n", | |
871 | pdata->gpio_pendown); | |
872 | return err; | |
873 | } | |
874 | ||
875 | ts->gpio_pendown = pdata->gpio_pendown; | |
876 | return 0; | |
877 | } | |
878 | ||
2e5a7bd9 | 879 | static int __devinit ads7846_probe(struct spi_device *spi) |
ffa458c1 | 880 | { |
ffa458c1 | 881 | struct ads7846 *ts; |
e8f462d2 | 882 | struct ads7846_packet *packet; |
a90f7e98 | 883 | struct input_dev *input_dev; |
2e5a7bd9 | 884 | struct ads7846_platform_data *pdata = spi->dev.platform_data; |
0b7018aa | 885 | struct spi_message *m; |
ffa458c1 | 886 | struct spi_transfer *x; |
de2defd9 | 887 | int vref; |
a90f7e98 | 888 | int err; |
ffa458c1 DB |
889 | |
890 | if (!spi->irq) { | |
2e5a7bd9 | 891 | dev_dbg(&spi->dev, "no IRQ?\n"); |
ffa458c1 DB |
892 | return -ENODEV; |
893 | } | |
894 | ||
895 | if (!pdata) { | |
2e5a7bd9 | 896 | dev_dbg(&spi->dev, "no platform data?\n"); |
ffa458c1 DB |
897 | return -ENODEV; |
898 | } | |
899 | ||
900 | /* don't exceed max specified sample rate */ | |
d93f70b2 | 901 | if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) { |
2e5a7bd9 | 902 | dev_dbg(&spi->dev, "f(sample) %d KHz?\n", |
d93f70b2 | 903 | (spi->max_speed_hz/SAMPLE_BITS)/1000); |
ffa458c1 DB |
904 | return -EINVAL; |
905 | } | |
906 | ||
9084533e DB |
907 | /* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except |
908 | * that even if the hardware can do that, the SPI controller driver | |
909 | * may not. So we stick to very-portable 8 bit words, both RX and TX. | |
ffa458c1 | 910 | */ |
9084533e | 911 | spi->bits_per_word = 8; |
230ffc8e | 912 | spi->mode = SPI_MODE_0; |
7937e86a ID |
913 | err = spi_setup(spi); |
914 | if (err < 0) | |
915 | return err; | |
ffa458c1 | 916 | |
a90f7e98 | 917 | ts = kzalloc(sizeof(struct ads7846), GFP_KERNEL); |
e8f462d2 | 918 | packet = kzalloc(sizeof(struct ads7846_packet), GFP_KERNEL); |
a90f7e98 | 919 | input_dev = input_allocate_device(); |
e8f462d2 | 920 | if (!ts || !packet || !input_dev) { |
a90f7e98 DT |
921 | err = -ENOMEM; |
922 | goto err_free_mem; | |
923 | } | |
ffa458c1 | 924 | |
2e5a7bd9 | 925 | dev_set_drvdata(&spi->dev, ts); |
ffa458c1 | 926 | |
e8f462d2 | 927 | ts->packet = packet; |
ffa458c1 | 928 | ts->spi = spi; |
a90f7e98 | 929 | ts->input = input_dev; |
7c6d0ee1 | 930 | ts->vref_mv = pdata->vref_mv; |
86579a4c | 931 | ts->swap_xy = pdata->swap_xy; |
ffa458c1 | 932 | |
c9cb2e3d | 933 | hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); |
ffa458c1 DB |
934 | ts->timer.function = ads7846_timer; |
935 | ||
7de90a8c ID |
936 | spin_lock_init(&ts->lock); |
937 | ||
ffa458c1 DB |
938 | ts->model = pdata->model ? : 7846; |
939 | ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100; | |
940 | ts->x_plate_ohms = pdata->x_plate_ohms ? : 400; | |
d5b415c9 | 941 | ts->pressure_max = pdata->pressure_max ? : ~0; |
da970e69 ID |
942 | |
943 | if (pdata->filter != NULL) { | |
944 | if (pdata->filter_init != NULL) { | |
945 | err = pdata->filter_init(pdata, &ts->filter_data); | |
946 | if (err < 0) | |
947 | goto err_free_mem; | |
948 | } | |
949 | ts->filter = pdata->filter; | |
950 | ts->filter_cleanup = pdata->filter_cleanup; | |
951 | } else if (pdata->debounce_max) { | |
d5b415c9 | 952 | ts->debounce_max = pdata->debounce_max; |
da970e69 ID |
953 | if (ts->debounce_max < 2) |
954 | ts->debounce_max = 2; | |
d5b415c9 ID |
955 | ts->debounce_tol = pdata->debounce_tol; |
956 | ts->debounce_rep = pdata->debounce_rep; | |
da970e69 ID |
957 | ts->filter = ads7846_debounce; |
958 | ts->filter_data = ts; | |
d5b415c9 | 959 | } else |
da970e69 | 960 | ts->filter = ads7846_no_filter; |
4d5975e5 EM |
961 | |
962 | err = setup_pendown(spi, ts); | |
963 | if (err) | |
964 | goto err_cleanup_filter; | |
ffa458c1 | 965 | |
1d25891f SH |
966 | if (pdata->penirq_recheck_delay_usecs) |
967 | ts->penirq_recheck_delay_usecs = | |
968 | pdata->penirq_recheck_delay_usecs; | |
969 | ||
fd746d54 EM |
970 | ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync; |
971 | ||
a6c2490f | 972 | snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev)); |
b58895f8 | 973 | snprintf(ts->name, sizeof(ts->name), "ADS%d Touchscreen", ts->model); |
ffa458c1 | 974 | |
b58895f8 | 975 | input_dev->name = ts->name; |
a90f7e98 | 976 | input_dev->phys = ts->phys; |
a5394fb0 | 977 | input_dev->dev.parent = &spi->dev; |
ffa458c1 | 978 | |
7b19ada2 JS |
979 | input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); |
980 | input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); | |
a90f7e98 | 981 | input_set_abs_params(input_dev, ABS_X, |
ffa458c1 DB |
982 | pdata->x_min ? : 0, |
983 | pdata->x_max ? : MAX_12BIT, | |
984 | 0, 0); | |
a90f7e98 | 985 | input_set_abs_params(input_dev, ABS_Y, |
ffa458c1 DB |
986 | pdata->y_min ? : 0, |
987 | pdata->y_max ? : MAX_12BIT, | |
988 | 0, 0); | |
a90f7e98 | 989 | input_set_abs_params(input_dev, ABS_PRESSURE, |
ffa458c1 DB |
990 | pdata->pressure_min, pdata->pressure_max, 0, 0); |
991 | ||
de2defd9 ID |
992 | vref = pdata->keep_vref_on; |
993 | ||
06a09124 MH |
994 | if (ts->model == 7873) { |
995 | /* The AD7873 is almost identical to the ADS7846 | |
996 | * keep VREF off during differential/ratiometric | |
997 | * conversion modes | |
998 | */ | |
999 | ts->model = 7846; | |
1000 | vref = 0; | |
1001 | } | |
1002 | ||
ffa458c1 DB |
1003 | /* set up the transfers to read touchscreen state; this assumes we |
1004 | * use formula #2 for pressure, not #3. | |
1005 | */ | |
0b7018aa | 1006 | m = &ts->msg[0]; |
ffa458c1 DB |
1007 | x = ts->xfer; |
1008 | ||
0b7018aa ID |
1009 | spi_message_init(m); |
1010 | ||
ffa458c1 | 1011 | /* y- still on; turn on only y+ (and ADC) */ |
e8f462d2 DT |
1012 | packet->read_y = READ_Y(vref); |
1013 | x->tx_buf = &packet->read_y; | |
ffa458c1 | 1014 | x->len = 1; |
0b7018aa | 1015 | spi_message_add_tail(x, m); |
d93f70b2 | 1016 | |
ffa458c1 | 1017 | x++; |
e8f462d2 | 1018 | x->rx_buf = &packet->tc.y; |
ffa458c1 | 1019 | x->len = 2; |
0b7018aa ID |
1020 | spi_message_add_tail(x, m); |
1021 | ||
e4f48861 SH |
1022 | /* the first sample after switching drivers can be low quality; |
1023 | * optionally discard it, using a second one after the signals | |
1024 | * have had enough time to stabilize. | |
1025 | */ | |
1026 | if (pdata->settle_delay_usecs) { | |
1027 | x->delay_usecs = pdata->settle_delay_usecs; | |
1028 | ||
1029 | x++; | |
e8f462d2 | 1030 | x->tx_buf = &packet->read_y; |
e4f48861 SH |
1031 | x->len = 1; |
1032 | spi_message_add_tail(x, m); | |
1033 | ||
1034 | x++; | |
e8f462d2 | 1035 | x->rx_buf = &packet->tc.y; |
e4f48861 SH |
1036 | x->len = 2; |
1037 | spi_message_add_tail(x, m); | |
1038 | } | |
1039 | ||
da970e69 | 1040 | m->complete = ads7846_rx_val; |
0b7018aa ID |
1041 | m->context = ts; |
1042 | ||
1043 | m++; | |
1044 | spi_message_init(m); | |
1045 | ||
1046 | /* turn y- off, x+ on, then leave in lowpower */ | |
1047 | x++; | |
e8f462d2 DT |
1048 | packet->read_x = READ_X(vref); |
1049 | x->tx_buf = &packet->read_x; | |
0b7018aa ID |
1050 | x->len = 1; |
1051 | spi_message_add_tail(x, m); | |
1052 | ||
1053 | x++; | |
e8f462d2 | 1054 | x->rx_buf = &packet->tc.x; |
0b7018aa ID |
1055 | x->len = 2; |
1056 | spi_message_add_tail(x, m); | |
1057 | ||
e4f48861 SH |
1058 | /* ... maybe discard first sample ... */ |
1059 | if (pdata->settle_delay_usecs) { | |
1060 | x->delay_usecs = pdata->settle_delay_usecs; | |
1061 | ||
1062 | x++; | |
e8f462d2 | 1063 | x->tx_buf = &packet->read_x; |
e4f48861 SH |
1064 | x->len = 1; |
1065 | spi_message_add_tail(x, m); | |
1066 | ||
1067 | x++; | |
e8f462d2 | 1068 | x->rx_buf = &packet->tc.x; |
e4f48861 SH |
1069 | x->len = 2; |
1070 | spi_message_add_tail(x, m); | |
1071 | } | |
1072 | ||
da970e69 | 1073 | m->complete = ads7846_rx_val; |
0b7018aa | 1074 | m->context = ts; |
ffa458c1 DB |
1075 | |
1076 | /* turn y+ off, x- on; we'll use formula #2 */ | |
1077 | if (ts->model == 7846) { | |
0b7018aa ID |
1078 | m++; |
1079 | spi_message_init(m); | |
1080 | ||
d93f70b2 | 1081 | x++; |
e8f462d2 DT |
1082 | packet->read_z1 = READ_Z1(vref); |
1083 | x->tx_buf = &packet->read_z1; | |
ffa458c1 | 1084 | x->len = 1; |
0b7018aa | 1085 | spi_message_add_tail(x, m); |
d93f70b2 | 1086 | |
ffa458c1 | 1087 | x++; |
e8f462d2 | 1088 | x->rx_buf = &packet->tc.z1; |
ffa458c1 | 1089 | x->len = 2; |
0b7018aa ID |
1090 | spi_message_add_tail(x, m); |
1091 | ||
e4f48861 SH |
1092 | /* ... maybe discard first sample ... */ |
1093 | if (pdata->settle_delay_usecs) { | |
1094 | x->delay_usecs = pdata->settle_delay_usecs; | |
1095 | ||
1096 | x++; | |
e8f462d2 | 1097 | x->tx_buf = &packet->read_z1; |
e4f48861 SH |
1098 | x->len = 1; |
1099 | spi_message_add_tail(x, m); | |
1100 | ||
1101 | x++; | |
e8f462d2 | 1102 | x->rx_buf = &packet->tc.z1; |
e4f48861 SH |
1103 | x->len = 2; |
1104 | spi_message_add_tail(x, m); | |
1105 | } | |
1106 | ||
da970e69 | 1107 | m->complete = ads7846_rx_val; |
0b7018aa ID |
1108 | m->context = ts; |
1109 | ||
1110 | m++; | |
1111 | spi_message_init(m); | |
ffa458c1 | 1112 | |
d93f70b2 | 1113 | x++; |
e8f462d2 DT |
1114 | packet->read_z2 = READ_Z2(vref); |
1115 | x->tx_buf = &packet->read_z2; | |
ffa458c1 | 1116 | x->len = 1; |
0b7018aa | 1117 | spi_message_add_tail(x, m); |
d93f70b2 | 1118 | |
ffa458c1 | 1119 | x++; |
e8f462d2 | 1120 | x->rx_buf = &packet->tc.z2; |
ffa458c1 | 1121 | x->len = 2; |
0b7018aa | 1122 | spi_message_add_tail(x, m); |
ffa458c1 | 1123 | |
e4f48861 SH |
1124 | /* ... maybe discard first sample ... */ |
1125 | if (pdata->settle_delay_usecs) { | |
1126 | x->delay_usecs = pdata->settle_delay_usecs; | |
1127 | ||
1128 | x++; | |
e8f462d2 | 1129 | x->tx_buf = &packet->read_z2; |
e4f48861 SH |
1130 | x->len = 1; |
1131 | spi_message_add_tail(x, m); | |
1132 | ||
1133 | x++; | |
e8f462d2 | 1134 | x->rx_buf = &packet->tc.z2; |
e4f48861 SH |
1135 | x->len = 2; |
1136 | spi_message_add_tail(x, m); | |
1137 | } | |
1138 | ||
da970e69 | 1139 | m->complete = ads7846_rx_val; |
0b7018aa ID |
1140 | m->context = ts; |
1141 | } | |
53a0ef89 ID |
1142 | |
1143 | /* power down */ | |
0b7018aa ID |
1144 | m++; |
1145 | spi_message_init(m); | |
1146 | ||
53a0ef89 | 1147 | x++; |
e8f462d2 DT |
1148 | packet->pwrdown = PWRDOWN; |
1149 | x->tx_buf = &packet->pwrdown; | |
53a0ef89 | 1150 | x->len = 1; |
0b7018aa | 1151 | spi_message_add_tail(x, m); |
53a0ef89 ID |
1152 | |
1153 | x++; | |
e8f462d2 | 1154 | x->rx_buf = &packet->dummy; |
53a0ef89 | 1155 | x->len = 2; |
d93f70b2 | 1156 | CS_CHANGE(*x); |
0b7018aa | 1157 | spi_message_add_tail(x, m); |
ffa458c1 | 1158 | |
0b7018aa ID |
1159 | m->complete = ads7846_rx; |
1160 | m->context = ts; | |
ffa458c1 | 1161 | |
d5b415c9 ID |
1162 | ts->last_msg = m; |
1163 | ||
91143379 GI |
1164 | ts->reg = regulator_get(&spi->dev, "vcc"); |
1165 | if (IS_ERR(ts->reg)) { | |
1166 | dev_err(&spi->dev, "unable to get regulator: %ld\n", | |
1167 | PTR_ERR(ts->reg)); | |
1168 | goto err_free_gpio; | |
1169 | } | |
1170 | ||
1171 | err = regulator_enable(ts->reg); | |
1172 | if (err) { | |
1173 | dev_err(&spi->dev, "unable to enable regulator: %d\n", err); | |
1174 | goto err_put_regulator; | |
1175 | } | |
1176 | ||
dace1453 | 1177 | if (request_irq(spi->irq, ads7846_irq, IRQF_TRIGGER_FALLING, |
9084533e | 1178 | spi->dev.driver->name, ts)) { |
c57c0a2a MR |
1179 | dev_info(&spi->dev, |
1180 | "trying pin change workaround on irq %d\n", spi->irq); | |
1181 | err = request_irq(spi->irq, ads7846_irq, | |
1182 | IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING, | |
1183 | spi->dev.driver->name, ts); | |
1184 | if (err) { | |
1185 | dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq); | |
91143379 | 1186 | goto err_disable_regulator; |
c57c0a2a | 1187 | } |
ffa458c1 | 1188 | } |
ffa458c1 | 1189 | |
2c8dc071 DB |
1190 | err = ads784x_hwmon_register(spi, ts); |
1191 | if (err) | |
1192 | goto err_free_irq; | |
1193 | ||
2e5a7bd9 | 1194 | dev_info(&spi->dev, "touchscreen, irq %d\n", spi->irq); |
ffa458c1 | 1195 | |
2c8dc071 | 1196 | /* take a first sample, leaving nPENIRQ active and vREF off; avoid |
ffa458c1 DB |
1197 | * the touchscreen, in case it's not connected. |
1198 | */ | |
2e5a7bd9 | 1199 | (void) ads7846_read12_ser(&spi->dev, |
ffa458c1 DB |
1200 | READ_12BIT_SER(vaux) | ADS_PD10_ALL_ON); |
1201 | ||
2c8dc071 | 1202 | err = sysfs_create_group(&spi->dev.kobj, &ads784x_attr_group); |
8dd51650 | 1203 | if (err) |
2c8dc071 | 1204 | goto err_remove_hwmon; |
7de90a8c | 1205 | |
a90f7e98 DT |
1206 | err = input_register_device(input_dev); |
1207 | if (err) | |
8dd51650 | 1208 | goto err_remove_attr_group; |
a90f7e98 | 1209 | |
fdba2bb1 RL |
1210 | device_init_wakeup(&spi->dev, pdata->wakeup); |
1211 | ||
ffa458c1 | 1212 | return 0; |
a90f7e98 | 1213 | |
8dd51650 | 1214 | err_remove_attr_group: |
2c8dc071 DB |
1215 | sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
1216 | err_remove_hwmon: | |
1217 | ads784x_hwmon_unregister(spi, ts); | |
8dd51650 | 1218 | err_free_irq: |
a90f7e98 | 1219 | free_irq(spi->irq, ts); |
91143379 GI |
1220 | err_disable_regulator: |
1221 | regulator_disable(ts->reg); | |
1222 | err_put_regulator: | |
1223 | regulator_put(ts->reg); | |
4d5975e5 EM |
1224 | err_free_gpio: |
1225 | if (ts->gpio_pendown != -1) | |
1226 | gpio_free(ts->gpio_pendown); | |
da970e69 ID |
1227 | err_cleanup_filter: |
1228 | if (ts->filter_cleanup) | |
1229 | ts->filter_cleanup(ts->filter_data); | |
a90f7e98 DT |
1230 | err_free_mem: |
1231 | input_free_device(input_dev); | |
e8f462d2 | 1232 | kfree(packet); |
a90f7e98 DT |
1233 | kfree(ts); |
1234 | return err; | |
ffa458c1 DB |
1235 | } |
1236 | ||
2e5a7bd9 | 1237 | static int __devexit ads7846_remove(struct spi_device *spi) |
ffa458c1 | 1238 | { |
2e5a7bd9 | 1239 | struct ads7846 *ts = dev_get_drvdata(&spi->dev); |
ffa458c1 | 1240 | |
fdba2bb1 RL |
1241 | device_init_wakeup(&spi->dev, false); |
1242 | ||
2c8dc071 | 1243 | ads784x_hwmon_unregister(spi, ts); |
7de90a8c ID |
1244 | input_unregister_device(ts->input); |
1245 | ||
2e5a7bd9 | 1246 | ads7846_suspend(spi, PMSG_SUSPEND); |
ffa458c1 | 1247 | |
2c8dc071 | 1248 | sysfs_remove_group(&spi->dev.kobj, &ads784x_attr_group); |
ffa458c1 | 1249 | |
7de90a8c | 1250 | free_irq(ts->spi->irq, ts); |
c9e617a5 ID |
1251 | /* suspend left the IRQ disabled */ |
1252 | enable_irq(ts->spi->irq); | |
7de90a8c | 1253 | |
91143379 GI |
1254 | regulator_disable(ts->reg); |
1255 | regulator_put(ts->reg); | |
1256 | ||
4d5975e5 EM |
1257 | if (ts->gpio_pendown != -1) |
1258 | gpio_free(ts->gpio_pendown); | |
1259 | ||
da970e69 ID |
1260 | if (ts->filter_cleanup) |
1261 | ts->filter_cleanup(ts->filter_data); | |
1262 | ||
e8f462d2 | 1263 | kfree(ts->packet); |
ffa458c1 DB |
1264 | kfree(ts); |
1265 | ||
2e5a7bd9 | 1266 | dev_dbg(&spi->dev, "unregistered touchscreen\n"); |
ffa458c1 DB |
1267 | return 0; |
1268 | } | |
1269 | ||
2e5a7bd9 DB |
1270 | static struct spi_driver ads7846_driver = { |
1271 | .driver = { | |
1272 | .name = "ads7846", | |
1273 | .bus = &spi_bus_type, | |
1274 | .owner = THIS_MODULE, | |
1275 | }, | |
ffa458c1 | 1276 | .probe = ads7846_probe, |
2e5a7bd9 | 1277 | .remove = __devexit_p(ads7846_remove), |
ffa458c1 DB |
1278 | .suspend = ads7846_suspend, |
1279 | .resume = ads7846_resume, | |
1280 | }; | |
1281 | ||
1282 | static int __init ads7846_init(void) | |
1283 | { | |
2e5a7bd9 | 1284 | return spi_register_driver(&ads7846_driver); |
ffa458c1 DB |
1285 | } |
1286 | module_init(ads7846_init); | |
1287 | ||
1288 | static void __exit ads7846_exit(void) | |
1289 | { | |
2e5a7bd9 | 1290 | spi_unregister_driver(&ads7846_driver); |
ffa458c1 DB |
1291 | } |
1292 | module_exit(ads7846_exit); | |
1293 | ||
1294 | MODULE_DESCRIPTION("ADS7846 TouchScreen Driver"); | |
1295 | MODULE_LICENSE("GPL"); | |
e0626e38 | 1296 | MODULE_ALIAS("spi:ads7846"); |