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