1 /*
2  * wm97xx-core.c  --  Touch screen driver core for Wolfson WM9705, WM9712
3  *                    and WM9713 AC97 Codecs.
4  *
5  * Copyright 2003, 2004, 2005, 2006, 2007, 2008 Wolfson Microelectronics PLC.
6  * Author: Liam Girdwood <lrg@slimlogic.co.uk>
7  * Parts Copyright : Ian Molton <spyro@f2s.com>
8  *                   Andrew Zabolotny <zap@homelink.ru>
9  *                   Russell King <rmk@arm.linux.org.uk>
10  *
11  *  This program is free software; you can redistribute  it and/or modify it
12  *  under  the terms of  the GNU General  Public License as published by the
13  *  Free Software Foundation;  either version 2 of the  License, or (at your
14  *  option) any later version.
15  *
16  * Notes:
17  *
18  *  Features:
19  *       - supports WM9705, WM9712, WM9713
20  *       - polling mode
21  *       - continuous mode (arch-dependent)
22  *       - adjustable rpu/dpp settings
23  *       - adjustable pressure current
24  *       - adjustable sample settle delay
25  *       - 4 and 5 wire touchscreens (5 wire is WM9712 only)
26  *       - pen down detection
27  *       - battery monitor
28  *       - sample AUX adcs
29  *       - power management
30  *       - codec GPIO
31  *       - codec event notification
32  * Todo
33  *       - Support for async sampling control for noisy LCDs.
34  *
35  */
36 
37 #include <linux/module.h>
38 #include <linux/moduleparam.h>
39 #include <linux/kernel.h>
40 #include <linux/init.h>
41 #include <linux/delay.h>
42 #include <linux/string.h>
43 #include <linux/proc_fs.h>
44 #include <linux/pm.h>
45 #include <linux/interrupt.h>
46 #include <linux/bitops.h>
47 #include <linux/workqueue.h>
48 #include <linux/wm97xx.h>
49 #include <linux/uaccess.h>
50 #include <linux/io.h>
51 
52 #define TS_NAME			"wm97xx"
53 #define WM_CORE_VERSION		"1.00"
54 #define DEFAULT_PRESSURE	0xb0c0
55 
56 
57 /*
58  * Touchscreen absolute values
59  *
60  * These parameters are used to help the input layer discard out of
61  * range readings and reduce jitter etc.
62  *
63  *   o min, max:- indicate the min and max values your touch screen returns
64  *   o fuzz:- use a higher number to reduce jitter
65  *
66  * The default values correspond to Mainstone II in QVGA mode
67  *
68  * Please read
69  * Documentation/input/input-programming.txt for more details.
70  */
71 
72 static int abs_x[3] = {350, 3900, 5};
73 module_param_array(abs_x, int, NULL, 0);
74 MODULE_PARM_DESC(abs_x, "Touchscreen absolute X min, max, fuzz");
75 
76 static int abs_y[3] = {320, 3750, 40};
77 module_param_array(abs_y, int, NULL, 0);
78 MODULE_PARM_DESC(abs_y, "Touchscreen absolute Y min, max, fuzz");
79 
80 static int abs_p[3] = {0, 150, 4};
81 module_param_array(abs_p, int, NULL, 0);
82 MODULE_PARM_DESC(abs_p, "Touchscreen absolute Pressure min, max, fuzz");
83 
84 /*
85  * wm97xx IO access, all IO locking done by AC97 layer
86  */
87 int wm97xx_reg_read(struct wm97xx *wm, u16 reg)
88 {
89 	if (wm->ac97)
90 		return wm->ac97->bus->ops->read(wm->ac97, reg);
91 	else
92 		return -1;
93 }
94 EXPORT_SYMBOL_GPL(wm97xx_reg_read);
95 
96 void wm97xx_reg_write(struct wm97xx *wm, u16 reg, u16 val)
97 {
98 	/* cache digitiser registers */
99 	if (reg >= AC97_WM9713_DIG1 && reg <= AC97_WM9713_DIG3)
100 		wm->dig[(reg - AC97_WM9713_DIG1) >> 1] = val;
101 
102 	/* cache gpio regs */
103 	if (reg >= AC97_GPIO_CFG && reg <= AC97_MISC_AFE)
104 		wm->gpio[(reg - AC97_GPIO_CFG) >> 1] = val;
105 
106 	/* wm9713 irq reg */
107 	if (reg == 0x5a)
108 		wm->misc = val;
109 
110 	if (wm->ac97)
111 		wm->ac97->bus->ops->write(wm->ac97, reg, val);
112 }
113 EXPORT_SYMBOL_GPL(wm97xx_reg_write);
114 
115 /**
116  * wm97xx_read_aux_adc - Read the aux adc.
117  * @wm: wm97xx device.
118  * @adcsel: codec ADC to be read
119  *
120  * Reads the selected AUX ADC.
121  */
122 
123 int wm97xx_read_aux_adc(struct wm97xx *wm, u16 adcsel)
124 {
125 	int power_adc = 0, auxval;
126 	u16 power = 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 	wm->codec->poll_sample(wm, adcsel, &auxval);
146 
147 	if (power_adc)
148 		wm97xx_reg_write(wm, AC97_EXTENDED_MID, power | 0x8000);
149 
150 	wm->codec->dig_restore(wm);
151 
152 	wm->pen_probably_down = 0;
153 
154 	mutex_unlock(&wm->codec_mutex);
155 	return auxval & 0xfff;
156 }
157 EXPORT_SYMBOL_GPL(wm97xx_read_aux_adc);
158 
159 /**
160  * wm97xx_get_gpio - Get the status of a codec GPIO.
161  * @wm: wm97xx device.
162  * @gpio: gpio
163  *
164  * Get the status of a codec GPIO pin
165  */
166 
167 enum wm97xx_gpio_status wm97xx_get_gpio(struct wm97xx *wm, u32 gpio)
168 {
169 	u16 status;
170 	enum wm97xx_gpio_status ret;
171 
172 	mutex_lock(&wm->codec_mutex);
173 	status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
174 
175 	if (status & gpio)
176 		ret = WM97XX_GPIO_HIGH;
177 	else
178 		ret = WM97XX_GPIO_LOW;
179 
180 	mutex_unlock(&wm->codec_mutex);
181 	return ret;
182 }
183 EXPORT_SYMBOL_GPL(wm97xx_get_gpio);
184 
185 /**
186  * wm97xx_set_gpio - Set the status of a codec GPIO.
187  * @wm: wm97xx device.
188  * @gpio: gpio
189  *
190  *
191  * Set the status of a codec GPIO pin
192  */
193 
194 void wm97xx_set_gpio(struct wm97xx *wm, u32 gpio,
195 				enum wm97xx_gpio_status status)
196 {
197 	u16 reg;
198 
199 	mutex_lock(&wm->codec_mutex);
200 	reg = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
201 
202 	if (status & WM97XX_GPIO_HIGH)
203 		reg |= gpio;
204 	else
205 		reg &= ~gpio;
206 
207 	if (wm->id == WM9712_ID2)
208 		wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg << 1);
209 	else
210 		wm97xx_reg_write(wm, AC97_GPIO_STATUS, reg);
211 	mutex_unlock(&wm->codec_mutex);
212 }
213 EXPORT_SYMBOL_GPL(wm97xx_set_gpio);
214 
215 /*
216  * Codec GPIO pin configuration, this sets pin direction, polarity,
217  * stickyness and wake up.
218  */
219 void wm97xx_config_gpio(struct wm97xx *wm, u32 gpio, enum wm97xx_gpio_dir dir,
220 		   enum wm97xx_gpio_pol pol, enum wm97xx_gpio_sticky sticky,
221 		   enum wm97xx_gpio_wake wake)
222 {
223 	u16 reg;
224 
225 	mutex_lock(&wm->codec_mutex);
226 	reg = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
227 
228 	if (pol == WM97XX_GPIO_POL_HIGH)
229 		reg |= gpio;
230 	else
231 		reg &= ~gpio;
232 
233 	wm97xx_reg_write(wm, AC97_GPIO_POLARITY, reg);
234 	reg = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
235 
236 	if (sticky == WM97XX_GPIO_STICKY)
237 		reg |= gpio;
238 	else
239 		reg &= ~gpio;
240 
241 	wm97xx_reg_write(wm, AC97_GPIO_STICKY, reg);
242 	reg = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
243 
244 	if (wake == WM97XX_GPIO_WAKE)
245 		reg |= gpio;
246 	else
247 		reg &= ~gpio;
248 
249 	wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, reg);
250 	reg = wm97xx_reg_read(wm, AC97_GPIO_CFG);
251 
252 	if (dir == WM97XX_GPIO_IN)
253 		reg |= gpio;
254 	else
255 		reg &= ~gpio;
256 
257 	wm97xx_reg_write(wm, AC97_GPIO_CFG, reg);
258 	mutex_unlock(&wm->codec_mutex);
259 }
260 EXPORT_SYMBOL_GPL(wm97xx_config_gpio);
261 
262 /*
263  * Configure the WM97XX_PRP value to use while system is suspended.
264  * If a value other than 0 is set then WM97xx pen detection will be
265  * left enabled in the configured mode while the system is in suspend,
266  * the device has users and suspend has not been disabled via the
267  * wakeup sysfs entries.
268  *
269  * @wm:   WM97xx device to configure
270  * @mode: WM97XX_PRP value to configure while suspended
271  */
272 void wm97xx_set_suspend_mode(struct wm97xx *wm, u16 mode)
273 {
274 	wm->suspend_mode = mode;
275 	device_init_wakeup(&wm->input_dev->dev, mode != 0);
276 }
277 EXPORT_SYMBOL_GPL(wm97xx_set_suspend_mode);
278 
279 /*
280  * Handle a pen down interrupt.
281  */
282 static void wm97xx_pen_irq_worker(struct work_struct *work)
283 {
284 	struct wm97xx *wm = container_of(work, struct wm97xx, pen_event_work);
285 	int pen_was_down = wm->pen_is_down;
286 
287 	/* do we need to enable the touch panel reader */
288 	if (wm->id == WM9705_ID2) {
289 		if (wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER_RD) &
290 					WM97XX_PEN_DOWN)
291 			wm->pen_is_down = 1;
292 		else
293 			wm->pen_is_down = 0;
294 	} else {
295 		u16 status, pol;
296 		mutex_lock(&wm->codec_mutex);
297 		status = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
298 		pol = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
299 
300 		if (WM97XX_GPIO_13 & pol & status) {
301 			wm->pen_is_down = 1;
302 			wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol &
303 						~WM97XX_GPIO_13);
304 		} else {
305 			wm->pen_is_down = 0;
306 			wm97xx_reg_write(wm, AC97_GPIO_POLARITY, pol |
307 					 WM97XX_GPIO_13);
308 		}
309 
310 		if (wm->id == WM9712_ID2)
311 			wm97xx_reg_write(wm, AC97_GPIO_STATUS, (status &
312 						~WM97XX_GPIO_13) << 1);
313 		else
314 			wm97xx_reg_write(wm, AC97_GPIO_STATUS, status &
315 						~WM97XX_GPIO_13);
316 		mutex_unlock(&wm->codec_mutex);
317 	}
318 
319 	/* If the system is not using continuous mode or it provides a
320 	 * pen down operation then we need to schedule polls while the
321 	 * pen is down.  Otherwise the machine driver is responsible
322 	 * for scheduling reads.
323 	 */
324 	if (!wm->mach_ops->acc_enabled || wm->mach_ops->acc_pen_down) {
325 		if (wm->pen_is_down && !pen_was_down) {
326 			/* Data is not availiable immediately on pen down */
327 			queue_delayed_work(wm->ts_workq, &wm->ts_reader, 1);
328 		}
329 
330 		/* Let ts_reader report the pen up for debounce. */
331 		if (!wm->pen_is_down && pen_was_down)
332 			wm->pen_is_down = 1;
333 	}
334 
335 	if (!wm->pen_is_down && wm->mach_ops->acc_enabled)
336 		wm->mach_ops->acc_pen_up(wm);
337 
338 	wm->mach_ops->irq_enable(wm, 1);
339 }
340 
341 /*
342  * Codec PENDOWN irq handler
343  *
344  * We have to disable the codec interrupt in the handler because it
345  * can take upto 1ms to clear the interrupt source. We schedule a task
346  * in a work queue to do the actual interaction with the chip.  The
347  * interrupt is then enabled again in the slow handler when the source
348  * has been cleared.
349  */
350 static irqreturn_t wm97xx_pen_interrupt(int irq, void *dev_id)
351 {
352 	struct wm97xx *wm = dev_id;
353 
354 	if (!work_pending(&wm->pen_event_work)) {
355 		wm->mach_ops->irq_enable(wm, 0);
356 		queue_work(wm->ts_workq, &wm->pen_event_work);
357 	}
358 
359 	return IRQ_HANDLED;
360 }
361 
362 /*
363  * initialise pen IRQ handler and workqueue
364  */
365 static int wm97xx_init_pen_irq(struct wm97xx *wm)
366 {
367 	u16 reg;
368 
369 	/* If an interrupt is supplied an IRQ enable operation must also be
370 	 * provided. */
371 	BUG_ON(!wm->mach_ops->irq_enable);
372 
373 	if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
374 			"wm97xx-pen", wm)) {
375 		dev_err(wm->dev,
376 			"Failed to register pen down interrupt, polling");
377 		wm->pen_irq = 0;
378 		return -EINVAL;
379 	}
380 
381 	/* Configure GPIO as interrupt source on WM971x */
382 	if (wm->id != WM9705_ID2) {
383 		BUG_ON(!wm->mach_ops->irq_gpio);
384 		reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
385 		wm97xx_reg_write(wm, AC97_MISC_AFE,
386 				reg & ~(wm->mach_ops->irq_gpio));
387 		reg = wm97xx_reg_read(wm, 0x5a);
388 		wm97xx_reg_write(wm, 0x5a, reg & ~0x0001);
389 	}
390 
391 	return 0;
392 }
393 
394 static int wm97xx_read_samples(struct wm97xx *wm)
395 {
396 	struct wm97xx_data data;
397 	int rc;
398 
399 	mutex_lock(&wm->codec_mutex);
400 
401 	if (wm->mach_ops && wm->mach_ops->acc_enabled)
402 		rc = wm->mach_ops->acc_pen_down(wm);
403 	else
404 		rc = wm->codec->poll_touch(wm, &data);
405 
406 	if (rc & RC_PENUP) {
407 		if (wm->pen_is_down) {
408 			wm->pen_is_down = 0;
409 			dev_dbg(wm->dev, "pen up\n");
410 			input_report_abs(wm->input_dev, ABS_PRESSURE, 0);
411 			input_report_key(wm->input_dev, BTN_TOUCH, 0);
412 			input_sync(wm->input_dev);
413 		} else if (!(rc & RC_AGAIN)) {
414 			/* We need high frequency updates only while
415 			* pen is down, the user never will be able to
416 			* touch screen faster than a few times per
417 			* second... On the other hand, when the user
418 			* is actively working with the touchscreen we
419 			* don't want to lose the quick response. So we
420 			* will slowly increase sleep time after the
421 			* pen is up and quicky restore it to ~one task
422 			* switch when pen is down again.
423 			*/
424 			if (wm->ts_reader_interval < HZ / 10)
425 				wm->ts_reader_interval++;
426 		}
427 
428 	} else if (rc & RC_VALID) {
429 		dev_dbg(wm->dev,
430 			"pen down: x=%x:%d, y=%x:%d, pressure=%x:%d\n",
431 			data.x >> 12, data.x & 0xfff, data.y >> 12,
432 			data.y & 0xfff, data.p >> 12, data.p & 0xfff);
433 		input_report_abs(wm->input_dev, ABS_X, data.x & 0xfff);
434 		input_report_abs(wm->input_dev, ABS_Y, data.y & 0xfff);
435 		input_report_abs(wm->input_dev, ABS_PRESSURE, data.p & 0xfff);
436 		input_report_key(wm->input_dev, BTN_TOUCH, 1);
437 		input_sync(wm->input_dev);
438 		wm->pen_is_down = 1;
439 		wm->ts_reader_interval = wm->ts_reader_min_interval;
440 	} else if (rc & RC_PENDOWN) {
441 		dev_dbg(wm->dev, "pen down\n");
442 		wm->pen_is_down = 1;
443 		wm->ts_reader_interval = wm->ts_reader_min_interval;
444 	}
445 
446 	mutex_unlock(&wm->codec_mutex);
447 	return rc;
448 }
449 
450 /*
451 * The touchscreen sample reader.
452 */
453 static void wm97xx_ts_reader(struct work_struct *work)
454 {
455 	int rc;
456 	struct wm97xx *wm = container_of(work, struct wm97xx, ts_reader.work);
457 
458 	BUG_ON(!wm->codec);
459 
460 	do {
461 		rc = wm97xx_read_samples(wm);
462 	} while (rc & RC_AGAIN);
463 
464 	if (wm->pen_is_down || !wm->pen_irq)
465 		queue_delayed_work(wm->ts_workq, &wm->ts_reader,
466 				   wm->ts_reader_interval);
467 }
468 
469 /**
470  * wm97xx_ts_input_open - Open the touch screen input device.
471  * @idev:	Input device to be opened.
472  *
473  * Called by the input sub system to open a wm97xx touchscreen device.
474  * Starts the touchscreen thread and touch digitiser.
475  */
476 static int wm97xx_ts_input_open(struct input_dev *idev)
477 {
478 	struct wm97xx *wm = input_get_drvdata(idev);
479 
480 	wm->ts_workq = create_singlethread_workqueue("kwm97xx");
481 	if (wm->ts_workq == NULL) {
482 		dev_err(wm->dev,
483 			"Failed to create workqueue\n");
484 		return -EINVAL;
485 	}
486 
487 	/* start digitiser */
488 	if (wm->mach_ops && wm->mach_ops->acc_enabled)
489 		wm->codec->acc_enable(wm, 1);
490 	wm->codec->dig_enable(wm, 1);
491 
492 	INIT_DELAYED_WORK(&wm->ts_reader, wm97xx_ts_reader);
493 	INIT_WORK(&wm->pen_event_work, wm97xx_pen_irq_worker);
494 
495 	wm->ts_reader_min_interval = HZ >= 100 ? HZ / 100 : 1;
496 	if (wm->ts_reader_min_interval < 1)
497 		wm->ts_reader_min_interval = 1;
498 	wm->ts_reader_interval = wm->ts_reader_min_interval;
499 
500 	wm->pen_is_down = 0;
501 	if (wm->pen_irq)
502 		wm97xx_init_pen_irq(wm);
503 	else
504 		dev_err(wm->dev, "No IRQ specified\n");
505 
506 	/* If we either don't have an interrupt for pen down events or
507 	 * failed to acquire it then we need to poll.
508 	 */
509 	if (wm->pen_irq == 0)
510 		queue_delayed_work(wm->ts_workq, &wm->ts_reader,
511 				   wm->ts_reader_interval);
512 
513 	return 0;
514 }
515 
516 /**
517  * wm97xx_ts_input_close - Close the touch screen input device.
518  * @idev:	Input device to be closed.
519  *
520  * Called by the input sub system to close a wm97xx touchscreen
521  * device.  Kills the touchscreen thread and stops the touch
522  * digitiser.
523  */
524 
525 static void wm97xx_ts_input_close(struct input_dev *idev)
526 {
527 	struct wm97xx *wm = input_get_drvdata(idev);
528 	u16 reg;
529 
530 	if (wm->pen_irq) {
531 		/* Return the interrupt to GPIO usage (disabling it) */
532 		if (wm->id != WM9705_ID2) {
533 			BUG_ON(!wm->mach_ops->irq_gpio);
534 			reg = wm97xx_reg_read(wm, AC97_MISC_AFE);
535 			wm97xx_reg_write(wm, AC97_MISC_AFE,
536 					 reg | wm->mach_ops->irq_gpio);
537 		}
538 
539 		free_irq(wm->pen_irq, wm);
540 	}
541 
542 	wm->pen_is_down = 0;
543 
544 	/* Balance out interrupt disables/enables */
545 	if (cancel_work_sync(&wm->pen_event_work))
546 		wm->mach_ops->irq_enable(wm, 1);
547 
548 	/* ts_reader rearms itself so we need to explicitly stop it
549 	 * before we destroy the workqueue.
550 	 */
551 	cancel_delayed_work_sync(&wm->ts_reader);
552 
553 	destroy_workqueue(wm->ts_workq);
554 
555 	/* stop digitiser */
556 	wm->codec->dig_enable(wm, 0);
557 	if (wm->mach_ops && wm->mach_ops->acc_enabled)
558 		wm->codec->acc_enable(wm, 0);
559 }
560 
561 static int wm97xx_probe(struct device *dev)
562 {
563 	struct wm97xx *wm;
564 	int ret = 0, id = 0;
565 
566 	wm = kzalloc(sizeof(struct wm97xx), GFP_KERNEL);
567 	if (!wm)
568 		return -ENOMEM;
569 	mutex_init(&wm->codec_mutex);
570 
571 	wm->dev = dev;
572 	dev->driver_data = wm;
573 	wm->ac97 = to_ac97_t(dev);
574 
575 	/* check that we have a supported codec */
576 	id = wm97xx_reg_read(wm, AC97_VENDOR_ID1);
577 	if (id != WM97XX_ID1) {
578 		dev_err(dev, "Device with vendor %04x is not a wm97xx\n", id);
579 		ret = -ENODEV;
580 		goto alloc_err;
581 	}
582 
583 	wm->id = wm97xx_reg_read(wm, AC97_VENDOR_ID2);
584 
585 	dev_info(wm->dev, "detected a wm97%02x codec\n", wm->id & 0xff);
586 
587 	switch (wm->id & 0xff) {
588 #ifdef CONFIG_TOUCHSCREEN_WM9705
589 	case 0x05:
590 		wm->codec = &wm9705_codec;
591 		break;
592 #endif
593 #ifdef CONFIG_TOUCHSCREEN_WM9712
594 	case 0x12:
595 		wm->codec = &wm9712_codec;
596 		break;
597 #endif
598 #ifdef CONFIG_TOUCHSCREEN_WM9713
599 	case 0x13:
600 		wm->codec = &wm9713_codec;
601 		break;
602 #endif
603 	default:
604 		dev_err(wm->dev, "Support for wm97%02x not compiled in.\n",
605 			wm->id & 0xff);
606 		ret = -ENODEV;
607 		goto alloc_err;
608 	}
609 
610 	/* set up physical characteristics */
611 	wm->codec->phy_init(wm);
612 
613 	/* load gpio cache */
614 	wm->gpio[0] = wm97xx_reg_read(wm, AC97_GPIO_CFG);
615 	wm->gpio[1] = wm97xx_reg_read(wm, AC97_GPIO_POLARITY);
616 	wm->gpio[2] = wm97xx_reg_read(wm, AC97_GPIO_STICKY);
617 	wm->gpio[3] = wm97xx_reg_read(wm, AC97_GPIO_WAKEUP);
618 	wm->gpio[4] = wm97xx_reg_read(wm, AC97_GPIO_STATUS);
619 	wm->gpio[5] = wm97xx_reg_read(wm, AC97_MISC_AFE);
620 
621 	wm->input_dev = input_allocate_device();
622 	if (wm->input_dev == NULL) {
623 		ret = -ENOMEM;
624 		goto alloc_err;
625 	}
626 
627 	/* set up touch configuration */
628 	wm->input_dev->name = "wm97xx touchscreen";
629 	wm->input_dev->phys = "wm97xx";
630 	wm->input_dev->open = wm97xx_ts_input_open;
631 	wm->input_dev->close = wm97xx_ts_input_close;
632 
633 	__set_bit(EV_ABS, wm->input_dev->evbit);
634 	__set_bit(EV_KEY, wm->input_dev->evbit);
635 	__set_bit(BTN_TOUCH, wm->input_dev->keybit);
636 
637 	input_set_abs_params(wm->input_dev, ABS_X, abs_x[0], abs_x[1],
638 			     abs_x[2], 0);
639 	input_set_abs_params(wm->input_dev, ABS_Y, abs_y[0], abs_y[1],
640 			     abs_y[2], 0);
641 	input_set_abs_params(wm->input_dev, ABS_PRESSURE, abs_p[0], abs_p[1],
642 			     abs_p[2], 0);
643 
644 	input_set_drvdata(wm->input_dev, wm);
645 	wm->input_dev->dev.parent = dev;
646 
647 	ret = input_register_device(wm->input_dev);
648 	if (ret < 0)
649 		goto dev_alloc_err;
650 
651 	/* register our battery device */
652 	wm->battery_dev = platform_device_alloc("wm97xx-battery", -1);
653 	if (!wm->battery_dev) {
654 		ret = -ENOMEM;
655 		goto batt_err;
656 	}
657 	platform_set_drvdata(wm->battery_dev, wm);
658 	wm->battery_dev->dev.parent = dev;
659 	ret = platform_device_add(wm->battery_dev);
660 	if (ret < 0)
661 		goto batt_reg_err;
662 
663 	/* register our extended touch device (for machine specific
664 	 * extensions) */
665 	wm->touch_dev = platform_device_alloc("wm97xx-touch", -1);
666 	if (!wm->touch_dev) {
667 		ret = -ENOMEM;
668 		goto touch_err;
669 	}
670 	platform_set_drvdata(wm->touch_dev, wm);
671 	wm->touch_dev->dev.parent = dev;
672 	ret = platform_device_add(wm->touch_dev);
673 	if (ret < 0)
674 		goto touch_reg_err;
675 
676 	return ret;
677 
678  touch_reg_err:
679 	platform_device_put(wm->touch_dev);
680  touch_err:
681 	platform_device_unregister(wm->battery_dev);
682 	wm->battery_dev = NULL;
683  batt_reg_err:
684 	platform_device_put(wm->battery_dev);
685  batt_err:
686 	input_unregister_device(wm->input_dev);
687 	wm->input_dev = NULL;
688  dev_alloc_err:
689 	input_free_device(wm->input_dev);
690  alloc_err:
691 	kfree(wm);
692 
693 	return ret;
694 }
695 
696 static int wm97xx_remove(struct device *dev)
697 {
698 	struct wm97xx *wm = dev_get_drvdata(dev);
699 
700 	platform_device_unregister(wm->battery_dev);
701 	platform_device_unregister(wm->touch_dev);
702 	input_unregister_device(wm->input_dev);
703 	kfree(wm);
704 
705 	return 0;
706 }
707 
708 #ifdef CONFIG_PM
709 static int wm97xx_suspend(struct device *dev, pm_message_t state)
710 {
711 	struct wm97xx *wm = dev_get_drvdata(dev);
712 	u16 reg;
713 	int suspend_mode;
714 
715 	if (device_may_wakeup(&wm->input_dev->dev))
716 		suspend_mode = wm->suspend_mode;
717 	else
718 		suspend_mode = 0;
719 
720 	if (wm->input_dev->users)
721 		cancel_delayed_work_sync(&wm->ts_reader);
722 
723 	/* Power down the digitiser (bypassing the cache for resume) */
724 	reg = wm97xx_reg_read(wm, AC97_WM97XX_DIGITISER2);
725 	reg &= ~WM97XX_PRP_DET_DIG;
726 	if (wm->input_dev->users)
727 		reg |= suspend_mode;
728 	wm->ac97->bus->ops->write(wm->ac97, AC97_WM97XX_DIGITISER2, reg);
729 
730 	/* WM9713 has an additional power bit - turn it off if there
731 	 * are no users or if suspend mode is zero. */
732 	if (wm->id == WM9713_ID2 &&
733 	    (!wm->input_dev->users || !suspend_mode)) {
734 		reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) | 0x8000;
735 		wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
736 	}
737 
738 	return 0;
739 }
740 
741 static int wm97xx_resume(struct device *dev)
742 {
743 	struct wm97xx *wm = dev_get_drvdata(dev);
744 
745 	/* restore digitiser and gpios */
746 	if (wm->id == WM9713_ID2) {
747 		wm97xx_reg_write(wm, AC97_WM9713_DIG1, wm->dig[0]);
748 		wm97xx_reg_write(wm, 0x5a, wm->misc);
749 		if (wm->input_dev->users) {
750 			u16 reg;
751 			reg = wm97xx_reg_read(wm, AC97_EXTENDED_MID) & 0x7fff;
752 			wm97xx_reg_write(wm, AC97_EXTENDED_MID, reg);
753 		}
754 	}
755 
756 	wm97xx_reg_write(wm, AC97_WM9713_DIG2, wm->dig[1]);
757 	wm97xx_reg_write(wm, AC97_WM9713_DIG3, wm->dig[2]);
758 
759 	wm97xx_reg_write(wm, AC97_GPIO_CFG, wm->gpio[0]);
760 	wm97xx_reg_write(wm, AC97_GPIO_POLARITY, wm->gpio[1]);
761 	wm97xx_reg_write(wm, AC97_GPIO_STICKY, wm->gpio[2]);
762 	wm97xx_reg_write(wm, AC97_GPIO_WAKEUP, wm->gpio[3]);
763 	wm97xx_reg_write(wm, AC97_GPIO_STATUS, wm->gpio[4]);
764 	wm97xx_reg_write(wm, AC97_MISC_AFE, wm->gpio[5]);
765 
766 	if (wm->input_dev->users && !wm->pen_irq) {
767 		wm->ts_reader_interval = wm->ts_reader_min_interval;
768 		queue_delayed_work(wm->ts_workq, &wm->ts_reader,
769 				   wm->ts_reader_interval);
770 	}
771 
772 	return 0;
773 }
774 
775 #else
776 #define wm97xx_suspend		NULL
777 #define wm97xx_resume		NULL
778 #endif
779 
780 /*
781  * Machine specific operations
782  */
783 int wm97xx_register_mach_ops(struct wm97xx *wm,
784 			     struct wm97xx_mach_ops *mach_ops)
785 {
786 	mutex_lock(&wm->codec_mutex);
787 	if (wm->mach_ops) {
788 		mutex_unlock(&wm->codec_mutex);
789 		return -EINVAL;
790 	}
791 	wm->mach_ops = mach_ops;
792 	mutex_unlock(&wm->codec_mutex);
793 
794 	return 0;
795 }
796 EXPORT_SYMBOL_GPL(wm97xx_register_mach_ops);
797 
798 void wm97xx_unregister_mach_ops(struct wm97xx *wm)
799 {
800 	mutex_lock(&wm->codec_mutex);
801 	wm->mach_ops = NULL;
802 	mutex_unlock(&wm->codec_mutex);
803 }
804 EXPORT_SYMBOL_GPL(wm97xx_unregister_mach_ops);
805 
806 static struct device_driver wm97xx_driver = {
807 	.name =		"wm97xx-ts",
808 	.bus =		&ac97_bus_type,
809 	.owner =	THIS_MODULE,
810 	.probe =	wm97xx_probe,
811 	.remove =	wm97xx_remove,
812 	.suspend =	wm97xx_suspend,
813 	.resume =	wm97xx_resume,
814 };
815 
816 static int __init wm97xx_init(void)
817 {
818 	return driver_register(&wm97xx_driver);
819 }
820 
821 static void __exit wm97xx_exit(void)
822 {
823 	driver_unregister(&wm97xx_driver);
824 }
825 
826 module_init(wm97xx_init);
827 module_exit(wm97xx_exit);
828 
829 /* Module information */
830 MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
831 MODULE_DESCRIPTION("WM97xx Core - Touch Screen / AUX ADC / GPIO Driver");
832 MODULE_LICENSE("GPL");
833