Merge tag 'ceph-for-4.13-rc8' of git://github.com/ceph/ceph-client
[linux/fpc-iii.git] / drivers / input / touchscreen / ad7879.c
blob196028c452106186a611f5232aeeb2593286f537
1 /*
2 * AD7879/AD7889 based touchscreen and GPIO driver
4 * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
6 * Licensed under the GPL-2 or later.
8 * History:
9 * Copyright (c) 2005 David Brownell
10 * Copyright (c) 2006 Nokia Corporation
11 * Various changes: Imre Deak <imre.deak@nokia.com>
13 * Using code from:
14 * - corgi_ts.c
15 * Copyright (C) 2004-2005 Richard Purdie
16 * - omap_ts.[hc], ads7846.h, ts_osk.c
17 * Copyright (C) 2002 MontaVista Software
18 * Copyright (C) 2004 Texas Instruments
19 * Copyright (C) 2005 Dirk Behme
20 * - ad7877.c
21 * Copyright (C) 2006-2008 Analog Devices Inc.
24 #include <linux/device.h>
25 #include <linux/delay.h>
26 #include <linux/input.h>
27 #include <linux/interrupt.h>
28 #include <linux/irq.h>
29 #include <linux/property.h>
30 #include <linux/regmap.h>
31 #include <linux/slab.h>
32 #include <linux/gpio.h>
34 #include <linux/input/touchscreen.h>
35 #include <linux/platform_data/ad7879.h>
36 #include <linux/module.h>
37 #include "ad7879.h"
39 #define AD7879_REG_ZEROS 0
40 #define AD7879_REG_CTRL1 1
41 #define AD7879_REG_CTRL2 2
42 #define AD7879_REG_CTRL3 3
43 #define AD7879_REG_AUX1HIGH 4
44 #define AD7879_REG_AUX1LOW 5
45 #define AD7879_REG_TEMP1HIGH 6
46 #define AD7879_REG_TEMP1LOW 7
47 #define AD7879_REG_XPLUS 8
48 #define AD7879_REG_YPLUS 9
49 #define AD7879_REG_Z1 10
50 #define AD7879_REG_Z2 11
51 #define AD7879_REG_AUXVBAT 12
52 #define AD7879_REG_TEMP 13
53 #define AD7879_REG_REVID 14
55 /* Control REG 1 */
56 #define AD7879_TMR(x) ((x & 0xFF) << 0)
57 #define AD7879_ACQ(x) ((x & 0x3) << 8)
58 #define AD7879_MODE_NOC (0 << 10) /* Do not convert */
59 #define AD7879_MODE_SCC (1 << 10) /* Single channel conversion */
60 #define AD7879_MODE_SEQ0 (2 << 10) /* Sequence 0 in Slave Mode */
61 #define AD7879_MODE_SEQ1 (3 << 10) /* Sequence 1 in Master Mode */
62 #define AD7879_MODE_INT (1 << 15) /* PENIRQ disabled INT enabled */
64 /* Control REG 2 */
65 #define AD7879_FCD(x) ((x & 0x3) << 0)
66 #define AD7879_RESET (1 << 4)
67 #define AD7879_MFS(x) ((x & 0x3) << 5)
68 #define AD7879_AVG(x) ((x & 0x3) << 7)
69 #define AD7879_SER (1 << 9) /* non-differential */
70 #define AD7879_DFR (0 << 9) /* differential */
71 #define AD7879_GPIOPOL (1 << 10)
72 #define AD7879_GPIODIR (1 << 11)
73 #define AD7879_GPIO_DATA (1 << 12)
74 #define AD7879_GPIO_EN (1 << 13)
75 #define AD7879_PM(x) ((x & 0x3) << 14)
76 #define AD7879_PM_SHUTDOWN (0)
77 #define AD7879_PM_DYN (1)
78 #define AD7879_PM_FULLON (2)
80 /* Control REG 3 */
81 #define AD7879_TEMPMASK_BIT (1<<15)
82 #define AD7879_AUXVBATMASK_BIT (1<<14)
83 #define AD7879_INTMODE_BIT (1<<13)
84 #define AD7879_GPIOALERTMASK_BIT (1<<12)
85 #define AD7879_AUXLOW_BIT (1<<11)
86 #define AD7879_AUXHIGH_BIT (1<<10)
87 #define AD7879_TEMPLOW_BIT (1<<9)
88 #define AD7879_TEMPHIGH_BIT (1<<8)
89 #define AD7879_YPLUS_BIT (1<<7)
90 #define AD7879_XPLUS_BIT (1<<6)
91 #define AD7879_Z1_BIT (1<<5)
92 #define AD7879_Z2_BIT (1<<4)
93 #define AD7879_AUX_BIT (1<<3)
94 #define AD7879_VBAT_BIT (1<<2)
95 #define AD7879_TEMP_BIT (1<<1)
97 enum {
98 AD7879_SEQ_YPOS = 0,
99 AD7879_SEQ_XPOS = 1,
100 AD7879_SEQ_Z1 = 2,
101 AD7879_SEQ_Z2 = 3,
102 AD7879_NR_SENSE = 4,
105 #define MAX_12BIT ((1<<12)-1)
106 #define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50)
108 struct ad7879 {
109 struct regmap *regmap;
110 struct device *dev;
111 struct input_dev *input;
112 struct timer_list timer;
113 #ifdef CONFIG_GPIOLIB
114 struct gpio_chip gc;
115 struct mutex mutex;
116 #endif
117 unsigned int irq;
118 bool disabled; /* P: input->mutex */
119 bool suspended; /* P: input->mutex */
120 bool swap_xy;
121 u16 conversion_data[AD7879_NR_SENSE];
122 char phys[32];
123 u8 first_conversion_delay;
124 u8 acquisition_time;
125 u8 averaging;
126 u8 pen_down_acc_interval;
127 u8 median;
128 u16 x_plate_ohms;
129 u16 cmd_crtl1;
130 u16 cmd_crtl2;
131 u16 cmd_crtl3;
132 int x;
133 int y;
134 int Rt;
137 static int ad7879_read(struct ad7879 *ts, u8 reg)
139 unsigned int val;
140 int error;
142 error = regmap_read(ts->regmap, reg, &val);
143 if (error) {
144 dev_err(ts->dev, "failed to read register %#02x: %d\n",
145 reg, error);
146 return error;
149 return val;
152 static int ad7879_write(struct ad7879 *ts, u8 reg, u16 val)
154 int error;
156 error = regmap_write(ts->regmap, reg, val);
157 if (error) {
158 dev_err(ts->dev,
159 "failed to write %#04x to register %#02x: %d\n",
160 val, reg, error);
161 return error;
164 return 0;
167 static int ad7879_report(struct ad7879 *ts)
169 struct input_dev *input_dev = ts->input;
170 unsigned Rt;
171 u16 x, y, z1, z2;
173 x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT;
174 y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT;
175 z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT;
176 z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT;
178 if (ts->swap_xy)
179 swap(x, y);
182 * The samples processed here are already preprocessed by the AD7879.
183 * The preprocessing function consists of a median and an averaging
184 * filter. The combination of these two techniques provides a robust
185 * solution, discarding the spurious noise in the signal and keeping
186 * only the data of interest. The size of both filters is
187 * programmable. (dev.platform_data, see linux/platform_data/ad7879.h)
188 * Other user-programmable conversion controls include variable
189 * acquisition time, and first conversion delay. Up to 16 averages can
190 * be taken per conversion.
193 if (likely(x && z1)) {
194 /* compute touch pressure resistance using equation #1 */
195 Rt = (z2 - z1) * x * ts->x_plate_ohms;
196 Rt /= z1;
197 Rt = (Rt + 2047) >> 12;
200 * Sample found inconsistent, pressure is beyond
201 * the maximum. Don't report it to user space.
203 if (Rt > input_abs_get_max(input_dev, ABS_PRESSURE))
204 return -EINVAL;
207 * Note that we delay reporting events by one sample.
208 * This is done to avoid reporting last sample of the
209 * touch sequence, which may be incomplete if finger
210 * leaves the surface before last reading is taken.
212 if (timer_pending(&ts->timer)) {
213 /* Touch continues */
214 input_report_key(input_dev, BTN_TOUCH, 1);
215 input_report_abs(input_dev, ABS_X, ts->x);
216 input_report_abs(input_dev, ABS_Y, ts->y);
217 input_report_abs(input_dev, ABS_PRESSURE, ts->Rt);
218 input_sync(input_dev);
221 ts->x = x;
222 ts->y = y;
223 ts->Rt = Rt;
225 return 0;
228 return -EINVAL;
231 static void ad7879_ts_event_release(struct ad7879 *ts)
233 struct input_dev *input_dev = ts->input;
235 input_report_abs(input_dev, ABS_PRESSURE, 0);
236 input_report_key(input_dev, BTN_TOUCH, 0);
237 input_sync(input_dev);
240 static void ad7879_timer(unsigned long handle)
242 struct ad7879 *ts = (void *)handle;
244 ad7879_ts_event_release(ts);
247 static irqreturn_t ad7879_irq(int irq, void *handle)
249 struct ad7879 *ts = handle;
251 regmap_bulk_read(ts->regmap, AD7879_REG_XPLUS,
252 ts->conversion_data, AD7879_NR_SENSE);
254 if (!ad7879_report(ts))
255 mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
257 return IRQ_HANDLED;
260 static void __ad7879_enable(struct ad7879 *ts)
262 ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
263 ad7879_write(ts, AD7879_REG_CTRL3, ts->cmd_crtl3);
264 ad7879_write(ts, AD7879_REG_CTRL1, ts->cmd_crtl1);
266 enable_irq(ts->irq);
269 static void __ad7879_disable(struct ad7879 *ts)
271 u16 reg = (ts->cmd_crtl2 & ~AD7879_PM(-1)) |
272 AD7879_PM(AD7879_PM_SHUTDOWN);
273 disable_irq(ts->irq);
275 if (del_timer_sync(&ts->timer))
276 ad7879_ts_event_release(ts);
278 ad7879_write(ts, AD7879_REG_CTRL2, reg);
282 static int ad7879_open(struct input_dev *input)
284 struct ad7879 *ts = input_get_drvdata(input);
286 /* protected by input->mutex */
287 if (!ts->disabled && !ts->suspended)
288 __ad7879_enable(ts);
290 return 0;
293 static void ad7879_close(struct input_dev* input)
295 struct ad7879 *ts = input_get_drvdata(input);
297 /* protected by input->mutex */
298 if (!ts->disabled && !ts->suspended)
299 __ad7879_disable(ts);
302 static int __maybe_unused ad7879_suspend(struct device *dev)
304 struct ad7879 *ts = dev_get_drvdata(dev);
306 mutex_lock(&ts->input->mutex);
308 if (!ts->suspended && !ts->disabled && ts->input->users)
309 __ad7879_disable(ts);
311 ts->suspended = true;
313 mutex_unlock(&ts->input->mutex);
315 return 0;
318 static int __maybe_unused ad7879_resume(struct device *dev)
320 struct ad7879 *ts = dev_get_drvdata(dev);
322 mutex_lock(&ts->input->mutex);
324 if (ts->suspended && !ts->disabled && ts->input->users)
325 __ad7879_enable(ts);
327 ts->suspended = false;
329 mutex_unlock(&ts->input->mutex);
331 return 0;
334 SIMPLE_DEV_PM_OPS(ad7879_pm_ops, ad7879_suspend, ad7879_resume);
335 EXPORT_SYMBOL(ad7879_pm_ops);
337 static void ad7879_toggle(struct ad7879 *ts, bool disable)
339 mutex_lock(&ts->input->mutex);
341 if (!ts->suspended && ts->input->users != 0) {
343 if (disable) {
344 if (ts->disabled)
345 __ad7879_enable(ts);
346 } else {
347 if (!ts->disabled)
348 __ad7879_disable(ts);
352 ts->disabled = disable;
354 mutex_unlock(&ts->input->mutex);
357 static ssize_t ad7879_disable_show(struct device *dev,
358 struct device_attribute *attr, char *buf)
360 struct ad7879 *ts = dev_get_drvdata(dev);
362 return sprintf(buf, "%u\n", ts->disabled);
365 static ssize_t ad7879_disable_store(struct device *dev,
366 struct device_attribute *attr,
367 const char *buf, size_t count)
369 struct ad7879 *ts = dev_get_drvdata(dev);
370 unsigned int val;
371 int error;
373 error = kstrtouint(buf, 10, &val);
374 if (error)
375 return error;
377 ad7879_toggle(ts, val);
379 return count;
382 static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store);
384 static struct attribute *ad7879_attributes[] = {
385 &dev_attr_disable.attr,
386 NULL
389 static const struct attribute_group ad7879_attr_group = {
390 .attrs = ad7879_attributes,
393 #ifdef CONFIG_GPIOLIB
394 static int ad7879_gpio_direction_input(struct gpio_chip *chip,
395 unsigned gpio)
397 struct ad7879 *ts = gpiochip_get_data(chip);
398 int err;
400 mutex_lock(&ts->mutex);
401 ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIODIR | AD7879_GPIOPOL;
402 err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
403 mutex_unlock(&ts->mutex);
405 return err;
408 static int ad7879_gpio_direction_output(struct gpio_chip *chip,
409 unsigned gpio, int level)
411 struct ad7879 *ts = gpiochip_get_data(chip);
412 int err;
414 mutex_lock(&ts->mutex);
415 ts->cmd_crtl2 &= ~AD7879_GPIODIR;
416 ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIOPOL;
417 if (level)
418 ts->cmd_crtl2 |= AD7879_GPIO_DATA;
419 else
420 ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
422 err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
423 mutex_unlock(&ts->mutex);
425 return err;
428 static int ad7879_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
430 struct ad7879 *ts = gpiochip_get_data(chip);
431 u16 val;
433 mutex_lock(&ts->mutex);
434 val = ad7879_read(ts, AD7879_REG_CTRL2);
435 mutex_unlock(&ts->mutex);
437 return !!(val & AD7879_GPIO_DATA);
440 static void ad7879_gpio_set_value(struct gpio_chip *chip,
441 unsigned gpio, int value)
443 struct ad7879 *ts = gpiochip_get_data(chip);
445 mutex_lock(&ts->mutex);
446 if (value)
447 ts->cmd_crtl2 |= AD7879_GPIO_DATA;
448 else
449 ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
451 ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
452 mutex_unlock(&ts->mutex);
455 static int ad7879_gpio_add(struct ad7879 *ts,
456 const struct ad7879_platform_data *pdata)
458 bool gpio_export;
459 int gpio_base;
460 int ret = 0;
462 if (pdata) {
463 gpio_export = pdata->gpio_export;
464 gpio_base = pdata->gpio_base;
465 } else {
466 gpio_export = device_property_read_bool(ts->dev,
467 "gpio-controller");
468 gpio_base = -1;
471 mutex_init(&ts->mutex);
473 if (gpio_export) {
474 ts->gc.direction_input = ad7879_gpio_direction_input;
475 ts->gc.direction_output = ad7879_gpio_direction_output;
476 ts->gc.get = ad7879_gpio_get_value;
477 ts->gc.set = ad7879_gpio_set_value;
478 ts->gc.can_sleep = 1;
479 ts->gc.base = gpio_base;
480 ts->gc.ngpio = 1;
481 ts->gc.label = "AD7879-GPIO";
482 ts->gc.owner = THIS_MODULE;
483 ts->gc.parent = ts->dev;
485 ret = devm_gpiochip_add_data(ts->dev, &ts->gc, ts);
486 if (ret)
487 dev_err(ts->dev, "failed to register gpio %d\n",
488 ts->gc.base);
491 return ret;
493 #else
494 static int ad7879_gpio_add(struct ad7879 *ts,
495 const struct ad7879_platform_data *pdata)
497 return 0;
499 #endif
501 static int ad7879_parse_dt(struct device *dev, struct ad7879 *ts)
503 int err;
504 u32 tmp;
506 err = device_property_read_u32(dev, "adi,resistance-plate-x", &tmp);
507 if (err) {
508 dev_err(dev, "failed to get resistance-plate-x property\n");
509 return err;
511 ts->x_plate_ohms = (u16)tmp;
513 device_property_read_u8(dev, "adi,first-conversion-delay",
514 &ts->first_conversion_delay);
515 device_property_read_u8(dev, "adi,acquisition-time",
516 &ts->acquisition_time);
517 device_property_read_u8(dev, "adi,median-filter-size", &ts->median);
518 device_property_read_u8(dev, "adi,averaging", &ts->averaging);
519 device_property_read_u8(dev, "adi,conversion-interval",
520 &ts->pen_down_acc_interval);
522 ts->swap_xy = device_property_read_bool(dev, "touchscreen-swapped-x-y");
524 return 0;
527 static void ad7879_cleanup_sysfs(void *_ts)
529 struct ad7879 *ts = _ts;
531 sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
534 int ad7879_probe(struct device *dev, struct regmap *regmap,
535 int irq, u16 bustype, u8 devid)
537 struct ad7879_platform_data *pdata = dev_get_platdata(dev);
538 struct ad7879 *ts;
539 struct input_dev *input_dev;
540 int err;
541 u16 revid;
543 if (irq <= 0) {
544 dev_err(dev, "No IRQ specified\n");
545 return -EINVAL;
548 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
549 if (!ts)
550 return -ENOMEM;
552 if (pdata) {
553 /* Platform data use swapped axis (backward compatibility) */
554 ts->swap_xy = !pdata->swap_xy;
556 ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
558 ts->first_conversion_delay = pdata->first_conversion_delay;
559 ts->acquisition_time = pdata->acquisition_time;
560 ts->averaging = pdata->averaging;
561 ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
562 ts->median = pdata->median;
563 } else {
564 err = ad7879_parse_dt(dev, ts);
565 if (err)
566 return err;
569 input_dev = devm_input_allocate_device(dev);
570 if (!input_dev) {
571 dev_err(dev, "Failed to allocate input device\n");
572 return -ENOMEM;
575 ts->dev = dev;
576 ts->input = input_dev;
577 ts->irq = irq;
578 ts->regmap = regmap;
580 setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts);
581 snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
583 input_dev->name = "AD7879 Touchscreen";
584 input_dev->phys = ts->phys;
585 input_dev->dev.parent = dev;
586 input_dev->id.bustype = bustype;
588 input_dev->open = ad7879_open;
589 input_dev->close = ad7879_close;
591 input_set_drvdata(input_dev, ts);
593 input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
595 if (pdata) {
596 input_set_abs_params(input_dev, ABS_X,
597 pdata->x_min ? : 0,
598 pdata->x_max ? : MAX_12BIT,
599 0, 0);
600 input_set_abs_params(input_dev, ABS_Y,
601 pdata->y_min ? : 0,
602 pdata->y_max ? : MAX_12BIT,
603 0, 0);
604 input_set_abs_params(input_dev, ABS_PRESSURE,
605 pdata->pressure_min,
606 pdata->pressure_max ? : ~0,
607 0, 0);
608 } else {
609 input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0);
610 input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
611 input_set_capability(input_dev, EV_ABS, ABS_PRESSURE);
612 touchscreen_parse_properties(input_dev, false, NULL);
613 if (!input_abs_get_max(input_dev, ABS_PRESSURE)) {
614 dev_err(dev, "Touchscreen pressure is not specified\n");
615 return -EINVAL;
619 err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
620 if (err < 0) {
621 dev_err(dev, "Failed to write %s\n", input_dev->name);
622 return err;
625 revid = ad7879_read(ts, AD7879_REG_REVID);
626 input_dev->id.product = (revid & 0xff);
627 input_dev->id.version = revid >> 8;
628 if (input_dev->id.product != devid) {
629 dev_err(dev, "Failed to probe %s (%x vs %x)\n",
630 input_dev->name, devid, revid);
631 return -ENODEV;
634 ts->cmd_crtl3 = AD7879_YPLUS_BIT |
635 AD7879_XPLUS_BIT |
636 AD7879_Z2_BIT |
637 AD7879_Z1_BIT |
638 AD7879_TEMPMASK_BIT |
639 AD7879_AUXVBATMASK_BIT |
640 AD7879_GPIOALERTMASK_BIT;
642 ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) | AD7879_DFR |
643 AD7879_AVG(ts->averaging) |
644 AD7879_MFS(ts->median) |
645 AD7879_FCD(ts->first_conversion_delay);
647 ts->cmd_crtl1 = AD7879_MODE_INT | AD7879_MODE_SEQ1 |
648 AD7879_ACQ(ts->acquisition_time) |
649 AD7879_TMR(ts->pen_down_acc_interval);
651 err = devm_request_threaded_irq(dev, ts->irq, NULL, ad7879_irq,
652 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
653 dev_name(dev), ts);
654 if (err) {
655 dev_err(dev, "Failed to request IRQ: %d\n", err);
656 return err;
659 __ad7879_disable(ts);
661 err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
662 if (err)
663 return err;
665 err = devm_add_action_or_reset(dev, ad7879_cleanup_sysfs, ts);
666 if (err)
667 return err;
669 err = ad7879_gpio_add(ts, pdata);
670 if (err)
671 return err;
673 err = input_register_device(input_dev);
674 if (err)
675 return err;
677 dev_set_drvdata(dev, ts);
679 return 0;
681 EXPORT_SYMBOL(ad7879_probe);
683 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
684 MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver");
685 MODULE_LICENSE("GPL");