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