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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2006-2008 Michael Hennerich, Analog Devices Inc.
4 *
5 * Description: AD7877 based touchscreen, sensor (ADCs), DAC and GPIO driver
6 * Based on: ads7846.c
7 *
8 * Bugs: Enter bugs at http://blackfin.uclinux.org/
9 *
10 * History:
11 * Copyright (c) 2005 David Brownell
12 * Copyright (c) 2006 Nokia Corporation
13 * Various changes: Imre Deak <[email protected]>
14 *
15 * Using code from:
16 * - corgi_ts.c
17 * Copyright (C) 2004-2005 Richard Purdie
18 * - omap_ts.[hc], ads7846.h, ts_osk.c
19 * Copyright (C) 2002 MontaVista Software
20 * Copyright (C) 2004 Texas Instruments
21 * Copyright (C) 2005 Dirk Behme
22 */
23
24
25#include <linux/device.h>
26#include <linux/delay.h>
27#include <linux/input.h>
28#include <linux/interrupt.h>
29#include <linux/pm.h>
30#include <linux/slab.h>
31#include <linux/spi/spi.h>
32#include <linux/spi/ad7877.h>
33#include <linux/module.h>
34#include <asm/irq.h>
35
36#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(100)
37
38#define MAX_SPI_FREQ_HZ 20000000
39#define MAX_12BIT ((1<<12)-1)
40
41#define AD7877_REG_ZEROS 0
42#define AD7877_REG_CTRL1 1
43#define AD7877_REG_CTRL2 2
44#define AD7877_REG_ALERT 3
45#define AD7877_REG_AUX1HIGH 4
46#define AD7877_REG_AUX1LOW 5
47#define AD7877_REG_BAT1HIGH 6
48#define AD7877_REG_BAT1LOW 7
49#define AD7877_REG_BAT2HIGH 8
50#define AD7877_REG_BAT2LOW 9
51#define AD7877_REG_TEMP1HIGH 10
52#define AD7877_REG_TEMP1LOW 11
53#define AD7877_REG_SEQ0 12
54#define AD7877_REG_SEQ1 13
55#define AD7877_REG_DAC 14
56#define AD7877_REG_NONE1 15
57#define AD7877_REG_EXTWRITE 15
58#define AD7877_REG_XPLUS 16
59#define AD7877_REG_YPLUS 17
60#define AD7877_REG_Z2 18
61#define AD7877_REG_aux1 19
62#define AD7877_REG_aux2 20
63#define AD7877_REG_aux3 21
64#define AD7877_REG_bat1 22
65#define AD7877_REG_bat2 23
66#define AD7877_REG_temp1 24
67#define AD7877_REG_temp2 25
68#define AD7877_REG_Z1 26
69#define AD7877_REG_GPIOCTRL1 27
70#define AD7877_REG_GPIOCTRL2 28
71#define AD7877_REG_GPIODATA 29
72#define AD7877_REG_NONE2 30
73#define AD7877_REG_NONE3 31
74
75#define AD7877_SEQ_YPLUS_BIT (1<<11)
76#define AD7877_SEQ_XPLUS_BIT (1<<10)
77#define AD7877_SEQ_Z2_BIT (1<<9)
78#define AD7877_SEQ_AUX1_BIT (1<<8)
79#define AD7877_SEQ_AUX2_BIT (1<<7)
80#define AD7877_SEQ_AUX3_BIT (1<<6)
81#define AD7877_SEQ_BAT1_BIT (1<<5)
82#define AD7877_SEQ_BAT2_BIT (1<<4)
83#define AD7877_SEQ_TEMP1_BIT (1<<3)
84#define AD7877_SEQ_TEMP2_BIT (1<<2)
85#define AD7877_SEQ_Z1_BIT (1<<1)
86
87enum {
88 AD7877_SEQ_YPOS = 0,
89 AD7877_SEQ_XPOS = 1,
90 AD7877_SEQ_Z2 = 2,
91 AD7877_SEQ_AUX1 = 3,
92 AD7877_SEQ_AUX2 = 4,
93 AD7877_SEQ_AUX3 = 5,
94 AD7877_SEQ_BAT1 = 6,
95 AD7877_SEQ_BAT2 = 7,
96 AD7877_SEQ_TEMP1 = 8,
97 AD7877_SEQ_TEMP2 = 9,
98 AD7877_SEQ_Z1 = 10,
99 AD7877_NR_SENSE = 11,
100};
101
102/* DAC Register Default RANGE 0 to Vcc, Volatge Mode, DAC On */
103#define AD7877_DAC_CONF 0x1
104
105/* If gpio3 is set AUX3/GPIO3 acts as GPIO Output */
106#define AD7877_EXTW_GPIO_3_CONF 0x1C4
107#define AD7877_EXTW_GPIO_DATA 0x200
108
109/* Control REG 2 */
110#define AD7877_TMR(x) ((x & 0x3) << 0)
111#define AD7877_REF(x) ((x & 0x1) << 2)
112#define AD7877_POL(x) ((x & 0x1) << 3)
113#define AD7877_FCD(x) ((x & 0x3) << 4)
114#define AD7877_PM(x) ((x & 0x3) << 6)
115#define AD7877_ACQ(x) ((x & 0x3) << 8)
116#define AD7877_AVG(x) ((x & 0x3) << 10)
117
118/* Control REG 1 */
119#define AD7877_SER (1 << 11) /* non-differential */
120#define AD7877_DFR (0 << 11) /* differential */
121
122#define AD7877_MODE_NOC (0) /* Do not convert */
123#define AD7877_MODE_SCC (1) /* Single channel conversion */
124#define AD7877_MODE_SEQ0 (2) /* Sequence 0 in Slave Mode */
125#define AD7877_MODE_SEQ1 (3) /* Sequence 1 in Master Mode */
126
127#define AD7877_CHANADD(x) ((x&0xF)<<7)
128#define AD7877_READADD(x) ((x)<<2)
129#define AD7877_WRITEADD(x) ((x)<<12)
130
131#define AD7877_READ_CHAN(x) (AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_SER | \
132 AD7877_MODE_SCC | AD7877_CHANADD(AD7877_REG_ ## x) | \
133 AD7877_READADD(AD7877_REG_ ## x))
134
135#define AD7877_MM_SEQUENCE (AD7877_SEQ_YPLUS_BIT | AD7877_SEQ_XPLUS_BIT | \
136 AD7877_SEQ_Z2_BIT | AD7877_SEQ_Z1_BIT)
137
138/*
139 * Non-touchscreen sensors only use single-ended conversions.
140 */
141
142struct ser_req {
143 u16 reset;
144 u16 ref_on;
145 u16 command;
146 struct spi_message msg;
147 struct spi_transfer xfer[6];
148
149 /*
150 * DMA (thus cache coherency maintenance) requires the
151 * transfer buffers to live in their own cache lines.
152 */
153 u16 sample ____cacheline_aligned;
154};
155
156struct ad7877 {
157 struct input_dev *input;
158 char phys[32];
159
160 struct spi_device *spi;
161 u16 model;
162 u16 vref_delay_usecs;
163 u16 x_plate_ohms;
164 u16 pressure_max;
165
166 u16 cmd_crtl1;
167 u16 cmd_crtl2;
168 u16 cmd_dummy;
169 u16 dac;
170
171 u8 stopacq_polarity;
172 u8 first_conversion_delay;
173 u8 acquisition_time;
174 u8 averaging;
175 u8 pen_down_acc_interval;
176
177 struct spi_transfer xfer[AD7877_NR_SENSE + 2];
178 struct spi_message msg;
179
180 struct mutex mutex;
181 bool disabled; /* P: mutex */
182 bool gpio3; /* P: mutex */
183 bool gpio4; /* P: mutex */
184
185 spinlock_t lock;
186 struct timer_list timer; /* P: lock */
187
188 /*
189 * DMA (thus cache coherency maintenance) requires the
190 * transfer buffers to live in their own cache lines.
191 */
192 u16 conversion_data[AD7877_NR_SENSE] ____cacheline_aligned;
193};
194
195static bool gpio3;
196module_param(gpio3, bool, 0);
197MODULE_PARM_DESC(gpio3, "If gpio3 is set to 1 AUX3 acts as GPIO3");
198
199static int ad7877_read(struct spi_device *spi, u16 reg)
200{
201 struct ser_req *req;
202 int status, ret;
203
204 req = kzalloc_obj(*req);
205 if (!req)
206 return -ENOMEM;
207
208 spi_message_init(&req->msg);
209
210 req->command = (u16) (AD7877_WRITEADD(AD7877_REG_CTRL1) |
211 AD7877_READADD(reg));
212 req->xfer[0].tx_buf = &req->command;
213 req->xfer[0].len = 2;
214 req->xfer[0].cs_change = 1;
215
216 req->xfer[1].rx_buf = &req->sample;
217 req->xfer[1].len = 2;
218
219 spi_message_add_tail(&req->xfer[0], &req->msg);
220 spi_message_add_tail(&req->xfer[1], &req->msg);
221
222 status = spi_sync(spi, &req->msg);
223 ret = status ? : req->sample;
224
225 kfree(req);
226
227 return ret;
228}
229
230static int ad7877_write(struct spi_device *spi, u16 reg, u16 val)
231{
232 struct ser_req *req;
233 int status;
234
235 req = kzalloc_obj(*req);
236 if (!req)
237 return -ENOMEM;
238
239 spi_message_init(&req->msg);
240
241 req->command = (u16) (AD7877_WRITEADD(reg) | (val & MAX_12BIT));
242 req->xfer[0].tx_buf = &req->command;
243 req->xfer[0].len = 2;
244
245 spi_message_add_tail(&req->xfer[0], &req->msg);
246
247 status = spi_sync(spi, &req->msg);
248
249 kfree(req);
250
251 return status;
252}
253
254static int ad7877_read_adc(struct spi_device *spi, unsigned command)
255{
256 struct ad7877 *ts = spi_get_drvdata(spi);
257 struct ser_req *req;
258 int status;
259 int sample;
260 int i;
261
262 req = kzalloc_obj(*req);
263 if (!req)
264 return -ENOMEM;
265
266 spi_message_init(&req->msg);
267
268 /* activate reference, so it has time to settle; */
269 req->ref_on = AD7877_WRITEADD(AD7877_REG_CTRL2) |
270 AD7877_POL(ts->stopacq_polarity) |
271 AD7877_AVG(0) | AD7877_PM(2) | AD7877_TMR(0) |
272 AD7877_ACQ(ts->acquisition_time) | AD7877_FCD(0);
273
274 req->reset = AD7877_WRITEADD(AD7877_REG_CTRL1) | AD7877_MODE_NOC;
275
276 req->command = (u16) command;
277
278 req->xfer[0].tx_buf = &req->reset;
279 req->xfer[0].len = 2;
280 req->xfer[0].cs_change = 1;
281
282 req->xfer[1].tx_buf = &req->ref_on;
283 req->xfer[1].len = 2;
284 req->xfer[1].delay.value = ts->vref_delay_usecs;
285 req->xfer[1].delay.unit = SPI_DELAY_UNIT_USECS;
286 req->xfer[1].cs_change = 1;
287
288 req->xfer[2].tx_buf = &req->command;
289 req->xfer[2].len = 2;
290 req->xfer[2].delay.value = ts->vref_delay_usecs;
291 req->xfer[2].delay.unit = SPI_DELAY_UNIT_USECS;
292 req->xfer[2].cs_change = 1;
293
294 req->xfer[3].rx_buf = &req->sample;
295 req->xfer[3].len = 2;
296 req->xfer[3].cs_change = 1;
297
298 req->xfer[4].tx_buf = &ts->cmd_crtl2; /*REF OFF*/
299 req->xfer[4].len = 2;
300 req->xfer[4].cs_change = 1;
301
302 req->xfer[5].tx_buf = &ts->cmd_crtl1; /*DEFAULT*/
303 req->xfer[5].len = 2;
304
305 /* group all the transfers together, so we can't interfere with
306 * reading touchscreen state; disable penirq while sampling
307 */
308 for (i = 0; i < 6; i++)
309 spi_message_add_tail(&req->xfer[i], &req->msg);
310
311 status = spi_sync(spi, &req->msg);
312 sample = req->sample;
313
314 kfree(req);
315
316 return status ? : sample;
317}
318
319static int ad7877_process_data(struct ad7877 *ts)
320{
321 struct input_dev *input_dev = ts->input;
322 unsigned Rt;
323 u16 x, y, z1, z2;
324
325 x = ts->conversion_data[AD7877_SEQ_XPOS] & MAX_12BIT;
326 y = ts->conversion_data[AD7877_SEQ_YPOS] & MAX_12BIT;
327 z1 = ts->conversion_data[AD7877_SEQ_Z1] & MAX_12BIT;
328 z2 = ts->conversion_data[AD7877_SEQ_Z2] & MAX_12BIT;
329
330 /*
331 * The samples processed here are already preprocessed by the AD7877.
332 * The preprocessing function consists of an averaging filter.
333 * The combination of 'first conversion delay' and averaging provides a robust solution,
334 * discarding the spurious noise in the signal and keeping only the data of interest.
335 * The size of the averaging filter is programmable. (dev.platform_data, see linux/spi/ad7877.h)
336 * Other user-programmable conversion controls include variable acquisition time,
337 * and first conversion delay. Up to 16 averages can be taken per conversion.
338 */
339
340 if (likely(x && z1)) {
341 /* compute touch pressure resistance using equation #1 */
342 Rt = (z2 - z1) * x * ts->x_plate_ohms;
343 Rt /= z1;
344 Rt = (Rt + 2047) >> 12;
345
346 /*
347 * Sample found inconsistent, pressure is beyond
348 * the maximum. Don't report it to user space.
349 */
350 if (Rt > ts->pressure_max)
351 return -EINVAL;
352
353 if (!timer_pending(&ts->timer))
354 input_report_key(input_dev, BTN_TOUCH, 1);
355
356 input_report_abs(input_dev, ABS_X, x);
357 input_report_abs(input_dev, ABS_Y, y);
358 input_report_abs(input_dev, ABS_PRESSURE, Rt);
359 input_sync(input_dev);
360
361 return 0;
362 }
363
364 return -EINVAL;
365}
366
367static inline void ad7877_ts_event_release(struct ad7877 *ts)
368{
369 struct input_dev *input_dev = ts->input;
370
371 input_report_abs(input_dev, ABS_PRESSURE, 0);
372 input_report_key(input_dev, BTN_TOUCH, 0);
373 input_sync(input_dev);
374}
375
376static void ad7877_timer(struct timer_list *t)
377{
378 struct ad7877 *ts = timer_container_of(ts, t, timer);
379
380 guard(spinlock_irqsave)(&ts->lock);
381 ad7877_ts_event_release(ts);
382}
383
384static irqreturn_t ad7877_irq(int irq, void *handle)
385{
386 struct ad7877 *ts = handle;
387 int error;
388
389 error = spi_sync(ts->spi, &ts->msg);
390 if (error) {
391 dev_err(&ts->spi->dev, "spi_sync --> %d\n", error);
392 goto out;
393 }
394
395 scoped_guard(spinlock_irqsave, &ts->lock) {
396 error = ad7877_process_data(ts);
397 if (error)
398 goto out;
399
400 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
401 }
402
403out:
404 return IRQ_HANDLED;
405}
406
407static void ad7877_disable(void *data)
408{
409 struct ad7877 *ts = data;
410
411 guard(mutex)(&ts->mutex);
412
413 if (!ts->disabled) {
414 ts->disabled = true;
415 disable_irq(ts->spi->irq);
416
417 if (timer_delete_sync(&ts->timer))
418 ad7877_ts_event_release(ts);
419 }
420
421 /*
422 * We know the chip's in lowpower mode since we always
423 * leave it that way after every request
424 */
425}
426
427static void ad7877_enable(struct ad7877 *ts)
428{
429 guard(mutex)(&ts->mutex);
430
431 if (ts->disabled) {
432 ts->disabled = false;
433 enable_irq(ts->spi->irq);
434 }
435}
436
437#define SHOW(name) static ssize_t \
438name ## _show(struct device *dev, struct device_attribute *attr, char *buf) \
439{ \
440 struct ad7877 *ts = dev_get_drvdata(dev); \
441 ssize_t v = ad7877_read_adc(ts->spi, \
442 AD7877_READ_CHAN(name)); \
443 if (v < 0) \
444 return v; \
445 return sprintf(buf, "%u\n", (unsigned) v); \
446} \
447static DEVICE_ATTR(name, S_IRUGO, name ## _show, NULL);
448
449SHOW(aux1)
450SHOW(aux2)
451SHOW(aux3)
452SHOW(bat1)
453SHOW(bat2)
454SHOW(temp1)
455SHOW(temp2)
456
457static ssize_t ad7877_disable_show(struct device *dev,
458 struct device_attribute *attr, char *buf)
459{
460 struct ad7877 *ts = dev_get_drvdata(dev);
461
462 return sprintf(buf, "%u\n", ts->disabled);
463}
464
465static ssize_t ad7877_disable_store(struct device *dev,
466 struct device_attribute *attr,
467 const char *buf, size_t count)
468{
469 struct ad7877 *ts = dev_get_drvdata(dev);
470 unsigned int val;
471 int error;
472
473 error = kstrtouint(buf, 10, &val);
474 if (error)
475 return error;
476
477 if (val)
478 ad7877_disable(ts);
479 else
480 ad7877_enable(ts);
481
482 return count;
483}
484
485static DEVICE_ATTR(disable, 0664, ad7877_disable_show, ad7877_disable_store);
486
487static ssize_t ad7877_dac_show(struct device *dev,
488 struct device_attribute *attr, char *buf)
489{
490 struct ad7877 *ts = dev_get_drvdata(dev);
491
492 return sprintf(buf, "%u\n", ts->dac);
493}
494
495static ssize_t ad7877_dac_store(struct device *dev,
496 struct device_attribute *attr,
497 const char *buf, size_t count)
498{
499 struct ad7877 *ts = dev_get_drvdata(dev);
500 unsigned int val;
501 int error;
502
503 error = kstrtouint(buf, 10, &val);
504 if (error)
505 return error;
506
507 guard(mutex)(&ts->mutex);
508 ts->dac = val & 0xFF;
509 ad7877_write(ts->spi, AD7877_REG_DAC, (ts->dac << 4) | AD7877_DAC_CONF);
510
511 return count;
512}
513
514static DEVICE_ATTR(dac, 0664, ad7877_dac_show, ad7877_dac_store);
515
516static ssize_t ad7877_gpio3_show(struct device *dev,
517 struct device_attribute *attr, char *buf)
518{
519 struct ad7877 *ts = dev_get_drvdata(dev);
520
521 return sprintf(buf, "%u\n", ts->gpio3);
522}
523
524static ssize_t ad7877_gpio3_store(struct device *dev,
525 struct device_attribute *attr,
526 const char *buf, size_t count)
527{
528 struct ad7877 *ts = dev_get_drvdata(dev);
529 unsigned int val;
530 int error;
531
532 error = kstrtouint(buf, 10, &val);
533 if (error)
534 return error;
535
536 guard(mutex)(&ts->mutex);
537 ts->gpio3 = !!val;
538 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA |
539 (ts->gpio4 << 4) | (ts->gpio3 << 5));
540
541 return count;
542}
543
544static DEVICE_ATTR(gpio3, 0664, ad7877_gpio3_show, ad7877_gpio3_store);
545
546static ssize_t ad7877_gpio4_show(struct device *dev,
547 struct device_attribute *attr, char *buf)
548{
549 struct ad7877 *ts = dev_get_drvdata(dev);
550
551 return sprintf(buf, "%u\n", ts->gpio4);
552}
553
554static ssize_t ad7877_gpio4_store(struct device *dev,
555 struct device_attribute *attr,
556 const char *buf, size_t count)
557{
558 struct ad7877 *ts = dev_get_drvdata(dev);
559 unsigned int val;
560 int error;
561
562 error = kstrtouint(buf, 10, &val);
563 if (error)
564 return error;
565
566 guard(mutex)(&ts->mutex);
567 ts->gpio4 = !!val;
568 ad7877_write(ts->spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_DATA |
569 (ts->gpio4 << 4) | (ts->gpio3 << 5));
570
571 return count;
572}
573
574static DEVICE_ATTR(gpio4, 0664, ad7877_gpio4_show, ad7877_gpio4_store);
575
576static struct attribute *ad7877_attributes[] = {
577 &dev_attr_temp1.attr,
578 &dev_attr_temp2.attr,
579 &dev_attr_aux1.attr,
580 &dev_attr_aux2.attr,
581 &dev_attr_aux3.attr,
582 &dev_attr_bat1.attr,
583 &dev_attr_bat2.attr,
584 &dev_attr_disable.attr,
585 &dev_attr_dac.attr,
586 &dev_attr_gpio3.attr,
587 &dev_attr_gpio4.attr,
588 NULL
589};
590
591static umode_t ad7877_attr_is_visible(struct kobject *kobj,
592 struct attribute *attr, int n)
593{
594 umode_t mode = attr->mode;
595
596 if (attr == &dev_attr_aux3.attr) {
597 if (gpio3)
598 mode = 0;
599 } else if (attr == &dev_attr_gpio3.attr) {
600 if (!gpio3)
601 mode = 0;
602 }
603
604 return mode;
605}
606
607static const struct attribute_group ad7877_group = {
608 .is_visible = ad7877_attr_is_visible,
609 .attrs = ad7877_attributes,
610};
611__ATTRIBUTE_GROUPS(ad7877);
612
613static void ad7877_setup_ts_def_msg(struct spi_device *spi, struct ad7877 *ts)
614{
615 struct spi_message *m;
616 int i;
617
618 ts->cmd_crtl2 = AD7877_WRITEADD(AD7877_REG_CTRL2) |
619 AD7877_POL(ts->stopacq_polarity) |
620 AD7877_AVG(ts->averaging) | AD7877_PM(1) |
621 AD7877_TMR(ts->pen_down_acc_interval) |
622 AD7877_ACQ(ts->acquisition_time) |
623 AD7877_FCD(ts->first_conversion_delay);
624
625 ad7877_write(spi, AD7877_REG_CTRL2, ts->cmd_crtl2);
626
627 ts->cmd_crtl1 = AD7877_WRITEADD(AD7877_REG_CTRL1) |
628 AD7877_READADD(AD7877_REG_XPLUS-1) |
629 AD7877_MODE_SEQ1 | AD7877_DFR;
630
631 ad7877_write(spi, AD7877_REG_CTRL1, ts->cmd_crtl1);
632
633 ts->cmd_dummy = 0;
634
635 m = &ts->msg;
636
637 spi_message_init(m);
638
639 m->context = ts;
640
641 ts->xfer[0].tx_buf = &ts->cmd_crtl1;
642 ts->xfer[0].len = 2;
643 ts->xfer[0].cs_change = 1;
644
645 spi_message_add_tail(&ts->xfer[0], m);
646
647 ts->xfer[1].tx_buf = &ts->cmd_dummy; /* Send ZERO */
648 ts->xfer[1].len = 2;
649 ts->xfer[1].cs_change = 1;
650
651 spi_message_add_tail(&ts->xfer[1], m);
652
653 for (i = 0; i < AD7877_NR_SENSE; i++) {
654 ts->xfer[i + 2].rx_buf = &ts->conversion_data[AD7877_SEQ_YPOS + i];
655 ts->xfer[i + 2].len = 2;
656 if (i < (AD7877_NR_SENSE - 1))
657 ts->xfer[i + 2].cs_change = 1;
658 spi_message_add_tail(&ts->xfer[i + 2], m);
659 }
660}
661
662static int ad7877_probe(struct spi_device *spi)
663{
664 struct ad7877 *ts;
665 struct input_dev *input_dev;
666 struct ad7877_platform_data *pdata = dev_get_platdata(&spi->dev);
667 int err;
668 u16 verify;
669
670 if (!spi->irq) {
671 dev_dbg(&spi->dev, "no IRQ?\n");
672 return -ENODEV;
673 }
674
675 if (!pdata) {
676 dev_dbg(&spi->dev, "no platform data?\n");
677 return -ENODEV;
678 }
679
680 /* don't exceed max specified SPI CLK frequency */
681 if (spi->max_speed_hz > MAX_SPI_FREQ_HZ) {
682 dev_dbg(&spi->dev, "SPI CLK %d Hz?\n",spi->max_speed_hz);
683 return -EINVAL;
684 }
685
686 spi->bits_per_word = 16;
687 err = spi_setup(spi);
688 if (err) {
689 dev_dbg(&spi->dev, "spi master doesn't support 16 bits/word\n");
690 return err;
691 }
692
693 ts = devm_kzalloc(&spi->dev, sizeof(struct ad7877), GFP_KERNEL);
694 if (!ts)
695 return -ENOMEM;
696
697 input_dev = devm_input_allocate_device(&spi->dev);
698 if (!input_dev)
699 return -ENOMEM;
700
701 err = devm_add_action_or_reset(&spi->dev, ad7877_disable, ts);
702 if (err)
703 return err;
704
705 spi_set_drvdata(spi, ts);
706 ts->spi = spi;
707 ts->input = input_dev;
708
709 timer_setup(&ts->timer, ad7877_timer, 0);
710 mutex_init(&ts->mutex);
711 spin_lock_init(&ts->lock);
712
713 ts->model = pdata->model ? : 7877;
714 ts->vref_delay_usecs = pdata->vref_delay_usecs ? : 100;
715 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
716 ts->pressure_max = pdata->pressure_max ? : ~0;
717
718 ts->stopacq_polarity = pdata->stopacq_polarity;
719 ts->first_conversion_delay = pdata->first_conversion_delay;
720 ts->acquisition_time = pdata->acquisition_time;
721 ts->averaging = pdata->averaging;
722 ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
723
724 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
725
726 input_dev->name = "AD7877 Touchscreen";
727 input_dev->phys = ts->phys;
728 input_dev->dev.parent = &spi->dev;
729
730 __set_bit(EV_KEY, input_dev->evbit);
731 __set_bit(BTN_TOUCH, input_dev->keybit);
732 __set_bit(EV_ABS, input_dev->evbit);
733 __set_bit(ABS_X, input_dev->absbit);
734 __set_bit(ABS_Y, input_dev->absbit);
735 __set_bit(ABS_PRESSURE, input_dev->absbit);
736
737 input_set_abs_params(input_dev, ABS_X,
738 pdata->x_min ? : 0,
739 pdata->x_max ? : MAX_12BIT,
740 0, 0);
741 input_set_abs_params(input_dev, ABS_Y,
742 pdata->y_min ? : 0,
743 pdata->y_max ? : MAX_12BIT,
744 0, 0);
745 input_set_abs_params(input_dev, ABS_PRESSURE,
746 pdata->pressure_min, pdata->pressure_max, 0, 0);
747
748 ad7877_write(spi, AD7877_REG_SEQ1, AD7877_MM_SEQUENCE);
749
750 verify = ad7877_read(spi, AD7877_REG_SEQ1);
751
752 if (verify != AD7877_MM_SEQUENCE) {
753 dev_err(&spi->dev, "%s: Failed to probe %s\n",
754 dev_name(&spi->dev), input_dev->name);
755 return -ENODEV;
756 }
757
758 if (gpio3)
759 ad7877_write(spi, AD7877_REG_EXTWRITE, AD7877_EXTW_GPIO_3_CONF);
760
761 ad7877_setup_ts_def_msg(spi, ts);
762
763 /* Request AD7877 /DAV GPIO interrupt */
764
765 err = devm_request_threaded_irq(&spi->dev, spi->irq, NULL, ad7877_irq,
766 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
767 spi->dev.driver->name, ts);
768 if (err) {
769 dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
770 return err;
771 }
772
773 err = input_register_device(input_dev);
774 if (err)
775 return err;
776
777 return 0;
778}
779
780static int ad7877_suspend(struct device *dev)
781{
782 struct ad7877 *ts = dev_get_drvdata(dev);
783
784 ad7877_disable(ts);
785
786 return 0;
787}
788
789static int ad7877_resume(struct device *dev)
790{
791 struct ad7877 *ts = dev_get_drvdata(dev);
792
793 ad7877_enable(ts);
794
795 return 0;
796}
797
798static DEFINE_SIMPLE_DEV_PM_OPS(ad7877_pm, ad7877_suspend, ad7877_resume);
799
800static struct spi_driver ad7877_driver = {
801 .driver = {
802 .name = "ad7877",
803 .dev_groups = ad7877_groups,
804 .pm = pm_sleep_ptr(&ad7877_pm),
805 },
806 .probe = ad7877_probe,
807};
808
809module_spi_driver(ad7877_driver);
810
811MODULE_AUTHOR("Michael Hennerich <[email protected]>");
812MODULE_DESCRIPTION("AD7877 touchscreen Driver");
813MODULE_LICENSE("GPL");
814MODULE_ALIAS("spi:ad7877");