Linux-libre 5.4.49-gnu
[librecmc/linux-libre.git] / drivers / input / touchscreen / wm97xx-core.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * wm97xx-core.c  --  Touch screen driver core for Wolfson WM9705, WM9712
4  *                    and WM9713 AC97 Codecs.
5  *
6  * Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC.
7  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
8  * Parts Copyright : Ian Molton <spyro@f2s.com>
9  *                   Andrew Zabolotny <zap@homelink.ru>
10  *                   Russell King <rmk@arm.linux.org.uk>
11  *
12  * Notes:
13  *
14  *  Features:
15  *       - supports WM9705, WM9712, WM9713
16  *       - polling mode
17  *       - continuous mode (arch-dependent)
18  *       - adjustable rpu/dpp settings
19  *       - adjustable pressure current
20  *       - adjustable sample settle delay
21  *       - 4 and 5 wire touchscreens (5 wire is WM9712 only)
22  *       - pen down detection
23  *       - battery monitor
24  *       - sample AUX adcs
25  *       - power management
26  *       - codec GPIO
27  *       - codec event notification
28  * Todo
29  *       - Support for async sampling control for noisy LCDs.
30  */
31
32 #include <linux/module.h>
33 #include <linux/moduleparam.h>
34 #include <linux/kernel.h>
35 #include <linux/init.h>
36 #include <linux/delay.h>
37 #include <linux/string.h>
38 #include <linux/proc_fs.h>
39 #include <linux/pm.h>
40 #include <linux/interrupt.h>
41 #include <linux/bitops.h>
42 #include <linux/mfd/wm97xx.h>
43 #include <linux/workqueue.h>
44 #include <linux/wm97xx.h>
45 #include <linux/uaccess.h>
46 #include <linux/io.h>
47 #include <linux/slab.h>
48
49 #define TS_NAME                 "wm97xx"
50 #define WM_CORE_VERSION         "1.00"
51 #define DEFAULT_PRESSURE        0xb0c0
52
53
54 /*
55  * Touchscreen absolute values
56  *
57  * These parameters are used to help the input layer discard out of
58  * range readings and reduce jitter etc.
59  *
60  *   o min, max:- indicate the min and max values your touch screen returns
61  *   o fuzz:- use a higher number to reduce jitter
62  *
63  * The default values correspond to Mainstone II in QVGA mode
64  *
65  * Please read
66  * Documentation/input/input-programming.rst for more details.
67  */
68
69 static int abs_x[3] = {150, 4000, 5};
70 module_param_array(abs_x, int, NULL, 0);
71 MODULE_PARM_DESC(abs_x, "Touchscreen absolute X min, max, fuzz");
72
73 static int abs_y[3] = {200, 4000, 40};
74 module_param_array(abs_y, int, NULL, 0);
75 MODULE_PARM_DESC(abs_y, "Touchscreen absolute Y min, max, fuzz");
76
77 static int abs_p[3] = {0, 150, 4};
78 module_param_array(abs_p, int, NULL, 0);
79 MODULE_PARM_DESC(abs_p, "Touchscreen absolute Pressure min, max, fuzz");
80
81 /*
82  * wm97xx IO access, all IO locking done by AC97 layer
83  */
84 int wm97xx_reg_read(struct wm97xx *wm, u16 reg)
85 {
86         if (wm->ac97)
87                 return wm->ac97->bus->ops->read(wm->ac97, reg);
88         else
89                 return -1;
90 }
91 EXPORT_SYMBOL_GPL(wm97xx_reg_read);
92
93 void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val)
94 {
95         /* cache digitiser registers */
96         if (reg >= AC97_WM9713_DIG1 && reg <= AC97_WM9713_DIG3)
97                 wm->dig[(reg - AC97_WM9713_DIG1) >> 1] = val;
98
99         /* cache gpio regs */
100         if (reg >= AC97_GPIO_CFG && reg <= AC97_MISC_AFE)
101                 wm->gpio[(reg - AC97_GPIO_CFG) >> 1] = val;
102
103         /* wm9713 irq reg */
104         if (reg == 0x5a)
105                 wm->misc = val;
106
107         if (wm->ac97)
108                 wm->ac97->bus->ops->write(wm->ac97, reg, val);
109 }
110 EXPORT_SYMBOL_GPL(wm97xx_reg_write);
111
112 /**
113  * wm97xx_read_aux_adc - Read the aux adc.
114  * @wm: wm97xx device.
115  * @adcsel: codec ADC to be read
116  *
117  * Reads the selected AUX ADC.
118  */
119
120 int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel)
121 {
122         int power_adc = 0, auxval;
123         u16 power = 0;
124         int rc = 0;
125         int timeout = 0;
126
127         /* get codec */
128         mutex_lock(&wm->codec_mutex);
129
130         /* When the touchscreen is not in use, we may have to power up
131          * the AUX ADC before we can use sample the AUX inputs->
132          */
133         if (wm->id == WM9713_ID2 &&
134             (power = wm97xx_reg_read(wm, AC97_EXTENDED_MID)) & 0x8000) {
135                 power_adc = 1;
136                 wm97xx_reg_write(wm, AC97_EXTENDED_MID, power & 0x7fff);
137         }
138
139         /* Prepare the codec for AUX reading */
140         wm->codec->aux_prepare(wm);
141
142         /* Turn polling mode on to read AUX ADC */
143         wm->pen_probably_down = 1;
144
145         while (rc != RC_VALID && timeout++ < 5)
146                 rc = wm->codec->poll_sample(wm, adcsel, &auxval);
147
148         if (power_adc)
149                 wm97xx_reg_write(wm, AC97_EXTENDED_MID, power | 0x8000);
150
151         wm->codec->dig_restore(wm);
152
153         wm->pen_probably_down = 0;
154
155         if (timeout >= 5) {
156                 dev_err(wm->dev,
157                         "timeout reading auxadc %d, disabling digitiser\n",
158                         adcsel);
159                 wm->codec->dig_enable(wm, false);
160         }
161
162         mutex_unlock(&wm->codec_mutex);
163         return (rc == RC_VALID ? auxval & 0xfff : -EBUSY);
164 }
165 EXPORT_SYMBOL_GPL(wm97xx_read_aux_adc);
166
167 /**
168  * wm97xx_get_gpio - Get the status of a codec GPIO.
169  * @wm: wm97xx device.
170  * @gpio: gpio
171  *
172  * Get the status of a codec GPIO pin
173  */
174
175 enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio)
176 {
177         u16 status;
178         enum wm97xx_gpio_status ret;
179
180         mutex_lock(&wm->codec_mutex);
181         status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
182
183         if (status & gpio)
184                 ret = WM97XX_GPIO_HIGH;
185         else
186                 ret = WM97XX_GPIO_LOW;
187
188         mutex_unlock(&wm->codec_mutex);
189         return ret;
190 }
191 EXPORT_SYMBOL_GPL(wm97xx_get_gpio);
192
193 /**
194  * wm97xx_set_gpio - Set the status of a codec GPIO.
195  * @wm: wm97xx device.
196  * @gpio: gpio
197  *
198  *
199  * Set the status of a codec GPIO pin
200  */
201
202 void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
203                                 enum wm97xx_gpio_status status)
204 {
205         u16 reg;
206
207         mutex_lock(&wm->codec_mutex);
208         reg = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
209
210         if (status == WM97XX_GPIO_HIGH)
211                 reg |= gpio;
212         else
213                 reg &= ~gpio;
214
215         if (wm->id == WM9712_ID2 && wm->variant != WM97xx_WM1613)
216                 wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg << 1);
217         else
218                 wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg);
219         mutex_unlock(&wm->codec_mutex);
220 }
221 EXPORT_SYMBOL_GPL(wm97xx_set_gpio);
222
223 /*
224  * Codec GPIO pin configuration, this sets pin direction, polarity,
225  * stickyness and wake up.
226  */
227 void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio, enum wm97xx_gpio_dir dir,
228                    enum wm97xx_gpio_pol pol, enum wm97xx_gpio_sticky sticky,
229                    enum wm97xx_gpio_wake wake)
230 {
231         u16 reg;
232
233         mutex_lock(&wm->codec_mutex);
234         reg = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
235
236         if (pol == WM97XX_GPIO_POL_HIGH)
237                 reg |= gpio;
238         else
239                 reg &= ~gpio;
240
241         wm97xx_reg_write(wm, AC97_GPIO_POLARITY, reg);
242         reg = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
243
244         if (sticky == WM97XX_GPIO_STICKY)
245                 reg |= gpio;
246         else
247                 reg &= ~gpio;
248
249         wm97xx_reg_write(wm, AC97_GPIO_STICKY, reg);
250         reg = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
251
252         if (wake == WM97XX_GPIO_WAKE)
253                 reg |= gpio;
254         else
255                 reg &= ~gpio;
256
257         wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, reg);
258         reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
259
260         if (dir == WM97XX_GPIO_IN)
261                 reg |= gpio;
262         else
263                 reg &= ~gpio;
264
265         wm97xx_reg_write(wm, AC97_GPIO_CFG, reg);
266         mutex_unlock(&wm->codec_mutex);
267 }
268 EXPORT_SYMBOL_GPL(wm97xx_config_gpio);
269
270 /*
271  * Configure the WM97XX_PRP value to use while system is suspended.
272  * If a value other than 0 is set then WM97xx pen detection will be
273  * left enabled in the configured mode while the system is in suspend,
274  * the device has users and suspend has not been disabled via the
275  * wakeup sysfs entries.
276  *
277  * @wm:   WM97xx device to configure
278  * @mode: WM97XX_PRP value to configure while suspended
279  */
280 void wm97xx_set_suspend_mode(struct wm97xx *wm, u16 mode)
281 {
282         wm->suspend_mode = mode;
283         device_init_wakeup(&wm->input_dev->dev, mode != 0);
284 }
285 EXPORT_SYMBOL_GPL(wm97xx_set_suspend_mode);
286
287 /*
288  * Handle a pen down interrupt.
289  */
290 static void wm97xx_pen_irq_worker(struct work_struct *work)
291 {
292         struct wm97xx *wm = container_of(work, struct wm97xx, pen_event_work);
293         int pen_was_down = wm->pen_is_down;
294
295         /* do we need to enable the touch panel reader */
296         if (wm->id == WM9705_ID2) {
297                 if (wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD) &
298                                         WM97XX_PEN_DOWN)
299                         wm->pen_is_down = 1;
300                 else
301                         wm->pen_is_down = 0;
302         } else {
303                 u16 status, pol;
304                 mutex_lock(&wm->codec_mutex);
305                 status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
306                 pol = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
307
308                 if (WM97XX_GPIO_13 & pol & status) {
309                         wm->pen_is_down = 1;
310                         wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol &
311                                                 ~WM97XX_GPIO_13);
312                 } else {
313                         wm->pen_is_down = 0;
314                         wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol |
315                                          WM97XX_GPIO_13);
316                 }
317
318                 if (wm->id == WM9712_ID2 && wm->variant != WM97xx_WM1613)
319                         wm97xx_reg_write(wm, AC97_GPIO_STATUS, (status &
320                                                 ~WM97XX_GPIO_13) << 1);
321                 else
322                         wm97xx_reg_write(wm, AC97_GPIO_STATUS, status &
323                                                 ~WM97XX_GPIO_13);
324                 mutex_unlock(&wm->codec_mutex);
325         }
326
327         /* If the system is not using continuous mode or it provides a
328          * pen down operation then we need to schedule polls while the
329          * pen is down.  Otherwise the machine driver is responsible
330          * for scheduling reads.
331          */
332         if (!wm->mach_ops->acc_enabled || wm->mach_ops->acc_pen_down) {
333                 if (wm->pen_is_down && !pen_was_down) {
334                         /* Data is not available immediately on pen down */
335                         queue_delayed_work(wm->ts_workq, &wm->ts_reader, 1);
336                 }
337
338                 /* Let ts_reader report the pen up for debounce. */
339                 if (!wm->pen_is_down && pen_was_down)
340                         wm->pen_is_down = 1;
341         }
342
343         if (!wm->pen_is_down && wm->mach_ops->acc_enabled)
344                 wm->mach_ops->acc_pen_up(wm);
345
346         wm->mach_ops->irq_enable(wm, 1);
347 }
348
349 /*
350  * Codec PENDOWN irq handler
351  *
352  * We have to disable the codec interrupt in the handler because it
353  * can take up to 1ms to clear the interrupt source. We schedule a task
354  * in a work queue to do the actual interaction with the chip.  The
355  * interrupt is then enabled again in the slow handler when the source
356  * has been cleared.
357  */
358 static irqreturn_t wm97xx_pen_interrupt(int irq, void *dev_id)
359 {
360         struct wm97xx *wm = dev_id;
361
362         if (!work_pending(&wm->pen_event_work)) {
363                 wm->mach_ops->irq_enable(wm, 0);
364                 queue_work(wm->ts_workq, &wm->pen_event_work);
365         }
366
367         return IRQ_HANDLED;
368 }
369
370 /*
371  * initialise pen IRQ handler and workqueue
372  */
373 static int wm97xx_init_pen_irq(struct wm97xx *wm)
374 {
375         u16 reg;
376
377         /* If an interrupt is supplied an IRQ enable operation must also be
378          * provided. */
379         BUG_ON(!wm->mach_ops->irq_enable);
380
381         if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
382                         "wm97xx-pen", wm)) {
383                 dev_err(wm->dev,
384                         "Failed to register pen down interrupt, polling");
385                 wm->pen_irq = 0;
386                 return -EINVAL;
387         }
388
389         /* Configure GPIO as interrupt source on WM971x */
390         if (wm->id != WM9705_ID2) {
391                 BUG_ON(!wm->mach_ops->irq_gpio);
392                 reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
393                 wm97xx_reg_write(wm, AC97_MISC_AFE,
394                                 reg & ~(wm->mach_ops->irq_gpio));
395                 reg = wm97xx_reg_read(wm, 0x5a);
396                 wm97xx_reg_write(wm, 0x5a, reg & ~0x0001);
397         }
398
399         return 0;
400 }
401
402 static int wm97xx_read_samples(struct wm97xx *wm)
403 {
404         struct wm97xx_data data;
405         int rc;
406
407         mutex_lock(&wm->codec_mutex);
408
409         if (wm->mach_ops && wm->mach_ops->acc_enabled)
410                 rc = wm->mach_ops->acc_pen_down(wm);
411         else
412                 rc = wm->codec->poll_touch(wm, &data);
413
414         if (rc & RC_PENUP) {
415                 if (wm->pen_is_down) {
416                         wm->pen_is_down = 0;
417                         dev_dbg(wm->dev, "pen up\n");
418                         input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
419                         input_report_key(wm->input_dev, BTN_TOUCH, 0);
420                         input_sync(wm->input_dev);
421                 } else if (!(rc & RC_AGAIN)) {
422                         /* We need high frequency updates only while
423                         * pen is down, the user never will be able to
424                         * touch screen faster than a few times per
425                         * second... On the other hand, when the user
426                         * is actively working with the touchscreen we
427                         * don't want to lose the quick response. So we
428                         * will slowly increase sleep time after the
429                         * pen is up and quicky restore it to ~one task
430                         * switch when pen is down again.
431                         */
432                         if (wm->ts_reader_interval < HZ / 10)
433                                 wm->ts_reader_interval++;
434                 }
435
436         } else if (rc & RC_VALID) {
437                 dev_dbg(wm->dev,
438                         "pen down: x=%x:%d, y=%x:%d, pressure=%x:%d\n",
439                         data.x >> 12, data.x & 0xfff, data.y >> 12,
440                         data.y & 0xfff, data.p >> 12, data.p & 0xfff);
441
442                 if (abs_x[0] > (data.x & 0xfff) ||
443                     abs_x[1] < (data.x & 0xfff) ||
444                     abs_y[0] > (data.y & 0xfff) ||
445                     abs_y[1] < (data.y & 0xfff)) {
446                         dev_dbg(wm->dev, "Measurement out of range, dropping it\n");
447                         rc = RC_AGAIN;
448                         goto out;
449                 }
450
451                 input_report_abs(wm->input_dev, ABS_X, data.x & 0xfff);
452                 input_report_abs(wm->input_dev, ABS_Y, data.y & 0xfff);
453                 input_report_abs(wm->input_dev, ABS_PRESSURE, data.p & 0xfff);
454                 input_report_key(wm->input_dev, BTN_TOUCH, 1);
455                 input_sync(wm->input_dev);
456                 wm->pen_is_down = 1;
457                 wm->ts_reader_interval = wm->ts_reader_min_interval;
458         } else if (rc & RC_PENDOWN) {
459                 dev_dbg(wm->dev, "pen down\n");
460                 wm->pen_is_down = 1;
461                 wm->ts_reader_interval = wm->ts_reader_min_interval;
462         }
463
464 out:
465         mutex_unlock(&wm->codec_mutex);
466         return rc;
467 }
468
469 /*
470 * The touchscreen sample reader.
471 */
472 static void wm97xx_ts_reader(struct work_struct *work)
473 {
474         int rc;
475         struct wm97xx *wm = container_of(work, struct wm97xx, ts_reader.work);
476
477         BUG_ON(!wm->codec);
478
479         do {
480                 rc = wm97xx_read_samples(wm);
481         } while (rc & RC_AGAIN);
482
483         if (wm->pen_is_down || !wm->pen_irq)
484                 queue_delayed_work(wm->ts_workq, &wm->ts_reader,
485                                    wm->ts_reader_interval);
486 }
487
488 /**
489  * wm97xx_ts_input_open - Open the touch screen input device.
490  * @idev:       Input device to be opened.
491  *
492  * Called by the input sub system to open a wm97xx touchscreen device.
493  * Starts the touchscreen thread and touch digitiser.
494  */
495 static int wm97xx_ts_input_open(struct input_dev *idev)
496 {
497         struct wm97xx *wm = input_get_drvdata(idev);
498
499         wm->ts_workq = alloc_ordered_workqueue("kwm97xx", 0);
500         if (wm->ts_workq == NULL) {
501                 dev_err(wm->dev,
502                         "Failed to create workqueue\n");
503                 return -EINVAL;
504         }
505
506         /* start digitiser */
507         if (wm->mach_ops && wm->mach_ops->acc_enabled)
508                 wm->codec->acc_enable(wm, 1);
509         wm->codec->dig_enable(wm, 1);
510
511         INIT_DELAYED_WORK(&wm->ts_reader, wm97xx_ts_reader);
512         INIT_WORK(&wm->pen_event_work, wm97xx_pen_irq_worker);
513
514         wm->ts_reader_min_interval = HZ >= 100 ? HZ / 100 : 1;
515         if (wm->ts_reader_min_interval < 1)
516                 wm->ts_reader_min_interval = 1;
517         wm->ts_reader_interval = wm->ts_reader_min_interval;
518
519         wm->pen_is_down = 0;
520         if (wm->pen_irq)
521                 wm97xx_init_pen_irq(wm);
522         else
523                 dev_err(wm->dev, "No IRQ specified\n");
524
525         /* If we either don't have an interrupt for pen down events or
526          * failed to acquire it then we need to poll.
527          */
528         if (wm->pen_irq == 0)
529                 queue_delayed_work(wm->ts_workq, &wm->ts_reader,
530                                    wm->ts_reader_interval);
531
532         return 0;
533 }
534
535 /**
536  * wm97xx_ts_input_close - Close the touch screen input device.
537  * @idev:       Input device to be closed.
538  *
539  * Called by the input sub system to close a wm97xx touchscreen
540  * device.  Kills the touchscreen thread and stops the touch
541  * digitiser.
542  */
543
544 static void wm97xx_ts_input_close(struct input_dev *idev)
545 {
546         struct wm97xx *wm = input_get_drvdata(idev);
547         u16 reg;
548
549         if (wm->pen_irq) {
550                 /* Return the interrupt to GPIO usage (disabling it) */
551                 if (wm->id != WM9705_ID2) {
552                         BUG_ON(!wm->mach_ops->irq_gpio);
553                         reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
554                         wm97xx_reg_write(wm, AC97_MISC_AFE,
555                                          reg | wm->mach_ops->irq_gpio);
556                 }
557
558                 free_irq(wm->pen_irq, wm);
559         }
560
561         wm->pen_is_down = 0;
562
563         /* Balance out interrupt disables/enables */
564         if (cancel_work_sync(&wm->pen_event_work))
565                 wm->mach_ops->irq_enable(wm, 1);
566
567         /* ts_reader rearms itself so we need to explicitly stop it
568          * before we destroy the workqueue.
569          */
570         cancel_delayed_work_sync(&wm->ts_reader);
571
572         destroy_workqueue(wm->ts_workq);
573
574         /* stop digitiser */
575         wm->codec->dig_enable(wm, 0);
576         if (wm->mach_ops && wm->mach_ops->acc_enabled)
577                 wm->codec->acc_enable(wm, 0);
578 }
579
580 static int wm97xx_register_touch(struct wm97xx *wm)
581 {
582         struct wm97xx_pdata *pdata = dev_get_platdata(wm->dev);
583         int ret;
584
585         wm->input_dev = devm_input_allocate_device(wm->dev);
586         if (wm->input_dev == NULL)
587                 return -ENOMEM;
588
589         /* set up touch configuration */
590         wm->input_dev->name = "wm97xx touchscreen";
591         wm->input_dev->phys = "wm97xx";
592         wm->input_dev->open = wm97xx_ts_input_open;
593         wm->input_dev->close = wm97xx_ts_input_close;
594
595         __set_bit(EV_ABS, wm->input_dev->evbit);
596         __set_bit(EV_KEY, wm->input_dev->evbit);
597         __set_bit(BTN_TOUCH, wm->input_dev->keybit);
598
599         input_set_abs_params(wm->input_dev, ABS_X, abs_x[0], abs_x[1],
600                              abs_x[2], 0);
601         input_set_abs_params(wm->input_dev, ABS_Y, abs_y[0], abs_y[1],
602                              abs_y[2], 0);
603         input_set_abs_params(wm->input_dev, ABS_PRESSURE, abs_p[0], abs_p[1],
604                              abs_p[2], 0);
605
606         input_set_drvdata(wm->input_dev, wm);
607         wm->input_dev->dev.parent = wm->dev;
608
609         ret = input_register_device(wm->input_dev);
610         if (ret)
611                 return ret;
612
613         /*
614          * register our extended touch device (for machine specific
615          * extensions)
616          */
617         wm->touch_dev = platform_device_alloc("wm97xx-touch", -1);
618         if (!wm->touch_dev) {
619                 ret = -ENOMEM;
620                 goto touch_err;
621         }
622         platform_set_drvdata(wm->touch_dev, wm);
623         wm->touch_dev->dev.parent = wm->dev;
624         wm->touch_dev->dev.platform_data = pdata;
625         ret = platform_device_add(wm->touch_dev);
626         if (ret < 0)
627                 goto touch_reg_err;
628
629         return 0;
630 touch_reg_err:
631         platform_device_put(wm->touch_dev);
632 touch_err:
633         input_unregister_device(wm->input_dev);
634         wm->input_dev = NULL;
635
636         return ret;
637 }
638
639 static void wm97xx_unregister_touch(struct wm97xx *wm)
640 {
641         platform_device_unregister(wm->touch_dev);
642         input_unregister_device(wm->input_dev);
643         wm->input_dev = NULL;
644 }
645
646 static int _wm97xx_probe(struct wm97xx *wm)
647 {
648         int id = 0;
649
650         mutex_init(&wm->codec_mutex);
651         dev_set_drvdata(wm->dev, wm);
652
653         /* check that we have a supported codec */
654         id = wm97xx_reg_read(wm, AC97_VENDOR_ID1);
655         if (id != WM97XX_ID1) {
656                 dev_err(wm->dev,
657                         "Device with vendor %04x is not a wm97xx\n", id);
658                 return -ENODEV;
659         }
660
661         wm->id = wm97xx_reg_read(wm, AC97_VENDOR_ID2);
662
663         wm->variant = WM97xx_GENERIC;
664
665         dev_info(wm->dev, "detected a wm97%02x codec\n", wm->id & 0xff);
666
667         switch (wm->id & 0xff) {
668 #ifdef CONFIG_TOUCHSCREEN_WM9705
669         case 0x05:
670                 wm->codec = &wm9705_codec;
671                 break;
672 #endif
673 #ifdef CONFIG_TOUCHSCREEN_WM9712
674         case 0x12:
675                 wm->codec = &wm9712_codec;
676                 break;
677 #endif
678 #ifdef CONFIG_TOUCHSCREEN_WM9713
679         case 0x13:
680                 wm->codec = &wm9713_codec;
681                 break;
682 #endif
683         default:
684                 dev_err(wm->dev, "Support for wm97%02x not compiled in.\n",
685                         wm->id & 0xff);
686                 return -ENODEV;
687         }
688
689         /* set up physical characteristics */
690         wm->codec->phy_init(wm);
691
692         /* load gpio cache */
693         wm->gpio[0] = wm97xx_reg_read(wm, AC97_GPIO_CFG);
694         wm->gpio[1] = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
695         wm->gpio[2] = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
696         wm->gpio[3] = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
697         wm->gpio[4] = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
698         wm->gpio[5] = wm97xx_reg_read(wm, AC97_MISC_AFE);
699
700         return wm97xx_register_touch(wm);
701 }
702
703 static void wm97xx_remove_battery(struct wm97xx *wm)
704 {
705         platform_device_unregister(wm->battery_dev);
706 }
707
708 static int wm97xx_add_battery(struct wm97xx *wm,
709                               struct wm97xx_batt_pdata *pdata)
710 {
711         int ret;
712
713         wm->battery_dev = platform_device_alloc("wm97xx-battery", -1);
714         if (!wm->battery_dev)
715                 return -ENOMEM;
716
717         platform_set_drvdata(wm->battery_dev, wm);
718         wm->battery_dev->dev.parent = wm->dev;
719         wm->battery_dev->dev.platform_data = pdata;
720         ret = platform_device_add(wm->battery_dev);
721         if (ret)
722                 platform_device_put(wm->battery_dev);
723
724         return ret;
725 }
726
727 static int wm97xx_probe(struct device *dev)
728 {
729         struct wm97xx *wm;
730         int ret;
731         struct wm97xx_pdata *pdata = dev_get_platdata(dev);
732
733         wm = devm_kzalloc(dev, sizeof(struct wm97xx), GFP_KERNEL);
734         if (!wm)
735                 return -ENOMEM;
736
737         wm->dev = dev;
738         wm->ac97 = to_ac97_t(dev);
739
740         ret =  _wm97xx_probe(wm);
741         if (ret)
742                 return ret;
743
744         ret = wm97xx_add_battery(wm, pdata ? pdata->batt_pdata : NULL);
745         if (ret < 0)
746                 goto batt_err;
747
748         return ret;
749
750 batt_err:
751         wm97xx_unregister_touch(wm);
752         return ret;
753 }
754
755 static int wm97xx_remove(struct device *dev)
756 {
757         struct wm97xx *wm = dev_get_drvdata(dev);
758
759         wm97xx_remove_battery(wm);
760         wm97xx_unregister_touch(wm);
761
762         return 0;
763 }
764
765 static int wm97xx_mfd_probe(struct platform_device *pdev)
766 {
767         struct wm97xx *wm;
768         struct wm97xx_platform_data *mfd_pdata = dev_get_platdata(&pdev->dev);
769         int ret;
770
771         wm = devm_kzalloc(&pdev->dev, sizeof(struct wm97xx), GFP_KERNEL);
772         if (!wm)
773                 return -ENOMEM;
774
775         wm->dev = &pdev->dev;
776         wm->ac97 = mfd_pdata->ac97;
777
778         ret =  _wm97xx_probe(wm);
779         if (ret)
780                 return ret;
781
782         ret = wm97xx_add_battery(wm, mfd_pdata->batt_pdata);
783         if (ret < 0)
784                 goto batt_err;
785
786         return ret;
787
788 batt_err:
789         wm97xx_unregister_touch(wm);
790         return ret;
791 }
792
793 static int wm97xx_mfd_remove(struct platform_device *pdev)
794 {
795         return wm97xx_remove(&pdev->dev);
796 }
797
798 static int __maybe_unused wm97xx_suspend(struct device *dev)
799 {
800         struct wm97xx *wm = dev_get_drvdata(dev);
801         u16 reg;
802         int suspend_mode;
803
804         if (device_may_wakeup(&wm->input_dev->dev))
805                 suspend_mode = wm->suspend_mode;
806         else
807                 suspend_mode = 0;
808
809         if (wm->input_dev->users)
810                 cancel_delayed_work_sync(&wm->ts_reader);
811
812         /* Power down the digitiser (bypassing the cache for resume) */
813         reg = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER2);
814         reg &= ~WM97XX_PRP_DET_DIG;
815         if (wm->input_dev->users)
816                 reg |= suspend_mode;
817         wm->ac97->bus->ops->write(wm->ac97, AC97_WM97XX_DIGITISER2, reg);
818
819         /* WM9713 has an additional power bit - turn it off if there
820          * are no users or if suspend mode is zero. */
821         if (wm->id == WM9713_ID2 &&
822             (!wm->input_dev->users || !suspend_mode)) {
823                 reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) | 0x8000;
824                 wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
825         }
826
827         return 0;
828 }
829
830 static int __maybe_unused wm97xx_resume(struct device *dev)
831 {
832         struct wm97xx *wm = dev_get_drvdata(dev);
833
834         /* restore digitiser and gpios */
835         if (wm->id == WM9713_ID2) {
836                 wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig[0]);
837                 wm97xx_reg_write(wm, 0x5a, wm->misc);
838                 if (wm->input_dev->users) {
839                         u16 reg;
840                         reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) & 0x7fff;
841                         wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
842                 }
843         }
844
845         wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig[1]);
846         wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2]);
847
848         wm97xx_reg_write(wm, AC97_GPIO_CFG, wm->gpio[0]);
849         wm97xx_reg_write(wm, AC97_GPIO_POLARITY, wm->gpio[1]);
850         wm97xx_reg_write(wm, AC97_GPIO_STICKY, wm->gpio[2]);
851         wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, wm->gpio[3]);
852         wm97xx_reg_write(wm, AC97_GPIO_STATUS, wm->gpio[4]);
853         wm97xx_reg_write(wm, AC97_MISC_AFE, wm->gpio[5]);
854
855         if (wm->input_dev->users && !wm->pen_irq) {
856                 wm->ts_reader_interval = wm->ts_reader_min_interval;
857                 queue_delayed_work(wm->ts_workq, &wm->ts_reader,
858                                    wm->ts_reader_interval);
859         }
860
861         return 0;
862 }
863
864 static SIMPLE_DEV_PM_OPS(wm97xx_pm_ops, wm97xx_suspend, wm97xx_resume);
865
866 /*
867  * Machine specific operations
868  */
869 int wm97xx_register_mach_ops(struct wm97xx *wm,
870                              struct wm97xx_mach_ops *mach_ops)
871 {
872         mutex_lock(&wm->codec_mutex);
873         if (wm->mach_ops) {
874                 mutex_unlock(&wm->codec_mutex);
875                 return -EINVAL;
876         }
877         wm->mach_ops = mach_ops;
878         mutex_unlock(&wm->codec_mutex);
879
880         return 0;
881 }
882 EXPORT_SYMBOL_GPL(wm97xx_register_mach_ops);
883
884 void wm97xx_unregister_mach_ops(struct wm97xx *wm)
885 {
886         mutex_lock(&wm->codec_mutex);
887         wm->mach_ops = NULL;
888         mutex_unlock(&wm->codec_mutex);
889 }
890 EXPORT_SYMBOL_GPL(wm97xx_unregister_mach_ops);
891
892 static struct device_driver wm97xx_driver = {
893         .name =         "wm97xx-ts",
894 #ifdef CONFIG_AC97_BUS
895         .bus =          &ac97_bus_type,
896 #endif
897         .owner =        THIS_MODULE,
898         .probe =        wm97xx_probe,
899         .remove =       wm97xx_remove,
900         .pm =           &wm97xx_pm_ops,
901 };
902
903 static struct platform_driver wm97xx_mfd_driver = {
904         .driver = {
905                 .name =         "wm97xx-ts",
906                 .pm =           &wm97xx_pm_ops,
907         },
908         .probe =        wm97xx_mfd_probe,
909         .remove =       wm97xx_mfd_remove,
910 };
911
912 static int __init wm97xx_init(void)
913 {
914         int ret;
915
916         ret = platform_driver_register(&wm97xx_mfd_driver);
917         if (ret)
918                 return ret;
919
920         if (IS_BUILTIN(CONFIG_AC97_BUS))
921                 ret =  driver_register(&wm97xx_driver);
922         return ret;
923 }
924
925 static void __exit wm97xx_exit(void)
926 {
927         if (IS_BUILTIN(CONFIG_AC97_BUS))
928                 driver_unregister(&wm97xx_driver);
929         platform_driver_unregister(&wm97xx_mfd_driver);
930 }
931
932 module_init(wm97xx_init);
933 module_exit(wm97xx_exit);
934
935 /* Module information */
936 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
937 MODULE_DESCRIPTION("WM97xx Core - Touch Screen / AUX ADC / GPIO Driver");
938 MODULE_LICENSE("GPL");