[linux-block.git] / drivers / input / touchscreen / mainstone-wm97xx.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * mainstone-wm97xx.c  --  Mainstone Continuous Touch screen driver for
 *                         Wolfson WM97xx AC97 Codecs.
 *
 * Copyright 2004, 2007 Wolfson Microelectronics PLC.
 * Author: Liam Girdwood <lrg@slimlogic.co.uk>
 * Parts Copyright : Ian Molton <spyro@f2s.com>
 *                   Andrew Zabolotny <zap@homelink.ru>
 *
 * Notes:
 *     This is a wm97xx extended touch driver to capture touch
 *     data in a continuous manner on the Intel XScale architecture
 *
 *  Features:
 *       - codecs supported:- WM9705, WM9712, WM9713
 *       - processors supported:- Intel XScale PXA25x, PXA26x, PXA27x
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/soc/pxa/cpu.h>
#include <linux/wm97xx.h>

#include <sound/pxa2xx-lib.h>

#include <asm/mach-types.h>

struct continuous {
	u16 id;    /* codec id */
	u8 code;   /* continuous code */
	u8 reads;  /* number of coord reads per read cycle */
	u32 speed; /* number of coords per second */
};

#define WM_READS(sp) ((sp / HZ) + 1)

static const struct continuous cinfo[] = {
	{ WM9705_ID2, 0, WM_READS(94),  94  },
	{ WM9705_ID2, 1, WM_READS(188), 188 },
	{ WM9705_ID2, 2, WM_READS(375), 375 },
	{ WM9705_ID2, 3, WM_READS(750), 750 },
	{ WM9712_ID2, 0, WM_READS(94),  94  },
	{ WM9712_ID2, 1, WM_READS(188), 188 },
	{ WM9712_ID2, 2, WM_READS(375), 375 },
	{ WM9712_ID2, 3, WM_READS(750), 750 },
	{ WM9713_ID2, 0, WM_READS(94),  94  },
	{ WM9713_ID2, 1, WM_READS(120), 120 },
	{ WM9713_ID2, 2, WM_READS(154), 154 },
	{ WM9713_ID2, 3, WM_READS(188), 188 },
};

/* continuous speed index */
static int sp_idx;
static struct gpio_desc *gpiod_irq;

/*
 * Pen sampling frequency (Hz) in continuous mode.
 */
static int cont_rate = 200;
module_param(cont_rate, int, 0);
MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");

/*
 * Pen down detection.
 *
 * This driver can either poll or use an interrupt to indicate a pen down
 * event. If the irq request fails then it will fall back to polling mode.
 */
static int pen_int;
module_param(pen_int, int, 0);
MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)");

/*
 * Pressure readback.
 *
 * Set to 1 to read back pen down pressure
 */
static int pressure;
module_param(pressure, int, 0);
MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");

/*
 * AC97 touch data slot.
 *
 * Touch screen readback data ac97 slot
 */
static int ac97_touch_slot = 5;
module_param(ac97_touch_slot, int, 0);
MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");


/* flush AC97 slot 5 FIFO on pxa machines */
static void wm97xx_acc_pen_up(struct wm97xx *wm)
{
	unsigned int count;

	msleep(1);

	if (cpu_is_pxa27x()) {
		while (pxa2xx_ac97_read_misr() & (1 << 2))
			pxa2xx_ac97_read_modr();
	} else if (cpu_is_pxa3xx()) {
		for (count = 0; count < 16; count++)
			pxa2xx_ac97_read_modr();
	}
}

static int wm97xx_acc_pen_down(struct wm97xx *wm)
{
	u16 x, y, p = 0x100 | WM97XX_ADCSEL_PRES;
	int reads = 0;
	static u16 last, tries;

	/* When the AC97 queue has been drained we need to allow time
	 * to buffer up samples otherwise we end up spinning polling
	 * for samples.  The controller can't have a suitably low
	 * threshold set to use the notifications it gives.
	 */
	msleep(1);

	if (tries > 5) {
		tries = 0;
		return RC_PENUP;
	}

	x = pxa2xx_ac97_read_modr();
	if (x == last) {
		tries++;
		return RC_AGAIN;
	}
	last = x;
	do {
		if (reads)
			x = pxa2xx_ac97_read_modr();
		y = pxa2xx_ac97_read_modr();
		if (pressure)
			p = pxa2xx_ac97_read_modr();

		dev_dbg(wm->dev, "Raw coordinates: x=%x, y=%x, p=%x\n",
			x, y, p);

		/* are samples valid */
		if ((x & WM97XX_ADCSEL_MASK) != WM97XX_ADCSEL_X ||
		    (y & WM97XX_ADCSEL_MASK) != WM97XX_ADCSEL_Y ||
		    (p & WM97XX_ADCSEL_MASK) != WM97XX_ADCSEL_PRES)
			goto up;

		/* coordinate is good */
		tries = 0;
		input_report_abs(wm->input_dev, ABS_X, x & 0xfff);
		input_report_abs(wm->input_dev, ABS_Y, y & 0xfff);
		input_report_abs(wm->input_dev, ABS_PRESSURE, p & 0xfff);
		input_report_key(wm->input_dev, BTN_TOUCH, (p != 0));
		input_sync(wm->input_dev);
		reads++;
	} while (reads < cinfo[sp_idx].reads);
up:
	return RC_PENDOWN | RC_AGAIN;
}

static int wm97xx_acc_startup(struct wm97xx *wm)
{
	int idx = 0, ret = 0;

	/* check we have a codec */
	if (wm->ac97 == NULL)
		return -ENODEV;

	/* Go you big red fire engine */
	for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
		if (wm->id != cinfo[idx].id)
			continue;
		sp_idx = idx;
		if (cont_rate <= cinfo[idx].speed)
			break;
	}
	wm->acc_rate = cinfo[sp_idx].code;
	wm->acc_slot = ac97_touch_slot;
	dev_info(wm->dev,
		 "mainstone accelerated touchscreen driver, %d samples/sec\n",
		 cinfo[sp_idx].speed);

	if (pen_int) {
		gpiod_irq = gpiod_get(wm->dev, "touch", GPIOD_IN);
		if (IS_ERR(gpiod_irq))
			pen_int = 0;
	}

	if (pen_int) {
		wm->pen_irq = gpiod_to_irq(gpiod_irq);
		irq_set_irq_type(wm->pen_irq, IRQ_TYPE_EDGE_BOTH);
	}

	/* codec specific irq config */
	if (pen_int) {
		switch (wm->id) {
		case WM9705_ID2:
			break;
		case WM9712_ID2:
		case WM9713_ID2:
			/* use PEN_DOWN GPIO 13 to assert IRQ on GPIO line 2 */
			wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
					   WM97XX_GPIO_POL_HIGH,
					   WM97XX_GPIO_STICKY,
					   WM97XX_GPIO_WAKE);
			wm97xx_config_gpio(wm, WM97XX_GPIO_2, WM97XX_GPIO_OUT,
					   WM97XX_GPIO_POL_HIGH,
					   WM97XX_GPIO_NOTSTICKY,
					   WM97XX_GPIO_NOWAKE);
			break;
		default:
			dev_err(wm->dev,
				"pen down irq not supported on this device\n");
			pen_int = 0;
			break;
		}
	}

	return ret;
}

static void wm97xx_acc_shutdown(struct wm97xx *wm)
{
	/* codec specific deconfig */
	if (pen_int) {
		if (gpiod_irq)
			gpiod_put(gpiod_irq);
		wm->pen_irq = 0;
	}
}

static struct wm97xx_mach_ops mainstone_mach_ops = {
	.acc_enabled	= 1,
	.acc_pen_up	= wm97xx_acc_pen_up,
	.acc_pen_down	= wm97xx_acc_pen_down,
	.acc_startup	= wm97xx_acc_startup,
	.acc_shutdown	= wm97xx_acc_shutdown,
	.irq_gpio	= WM97XX_GPIO_2,
};

static int mainstone_wm97xx_probe(struct platform_device *pdev)
{
	struct wm97xx *wm = platform_get_drvdata(pdev);

	return wm97xx_register_mach_ops(wm, &mainstone_mach_ops);
}

static int mainstone_wm97xx_remove(struct platform_device *pdev)
{
	struct wm97xx *wm = platform_get_drvdata(pdev);

	wm97xx_unregister_mach_ops(wm);

	return 0;
}

static struct platform_driver mainstone_wm97xx_driver = {
	.probe	= mainstone_wm97xx_probe,
	.remove	= mainstone_wm97xx_remove,
	.driver	= {
		.name	= "wm97xx-touch",
	},
};
module_platform_driver(mainstone_wm97xx_driver);

/* Module information */
MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
MODULE_DESCRIPTION("wm97xx continuous touch driver for mainstone");
MODULE_LICENSE("GPL");
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
4db8a5f2 MB	2	/*
	3	* mainstone-wm97xx.c -- Mainstone Continuous Touch screen driver for
	4	* Wolfson WM97xx AC97 Codecs.
	5	*
	6	* Copyright 2004, 2007 Wolfson Microelectronics PLC.
b8d055a8	7	* Author: Liam Girdwood <lrg@slimlogic.co.uk>
4db8a5f2 MB	8	* Parts Copyright : Ian Molton <spyro@f2s.com>
	9	* Andrew Zabolotny <zap@homelink.ru>
	10	*
4db8a5f2 MB	11	* Notes:
4db8a5f2 MB	12	* This is a wm97xx extended touch driver to capture touch
af901ca1	13	* data in a continuous manner on the Intel XScale architecture
4db8a5f2 MB	14	*
	15	* Features:
	16	* - codecs supported:- WM9705, WM9712, WM9713
	17	* - processors supported:- Intel XScale PXA25x, PXA26x, PXA27x
4db8a5f2 MB	18	*/
	19
	20	#include <linux/module.h>
	21	#include <linux/moduleparam.h>
4db8a5f2	22	#include <linux/kernel.h>
4db8a5f2	23	#include <linux/delay.h>
0ca7231f	24	#include <linux/gpio/consumer.h>
4db8a5f2 MB	25	#include <linux/irq.h>
4db8a5f2 MB	26	#include <linux/interrupt.h>
4db8a5f2	27	#include <linux/io.h>
7b8a0b90 AB	28	#include <linux/soc/pxa/cpu.h>
7b8a0b90 AB	29	#include <linux/wm97xx.h>
b833306f	30
e217b085	31	#include <sound/pxa2xx-lib.h>
4db8a5f2	32
b833306f	33	#include <asm/mach-types.h>
4db8a5f2 MB	34
	35	struct continuous {
	36	u16 id; /* codec id */
	37	u8 code; /* continuous code */
	38	u8 reads; /* number of coord reads per read cycle */
	39	u32 speed; /* number of coords per second */
	40	};
	41
	42	#define WM_READS(sp) ((sp / HZ) + 1)
	43
	44	static const struct continuous cinfo[] = {
7b8a0b90 AB	45	{ WM9705_ID2, 0, WM_READS(94), 94 },
	46	{ WM9705_ID2, 1, WM_READS(188), 188 },
	47	{ WM9705_ID2, 2, WM_READS(375), 375 },
	48	{ WM9705_ID2, 3, WM_READS(750), 750 },
	49	{ WM9712_ID2, 0, WM_READS(94), 94 },
	50	{ WM9712_ID2, 1, WM_READS(188), 188 },
	51	{ WM9712_ID2, 2, WM_READS(375), 375 },
	52	{ WM9712_ID2, 3, WM_READS(750), 750 },
	53	{ WM9713_ID2, 0, WM_READS(94), 94 },
	54	{ WM9713_ID2, 1, WM_READS(120), 120 },
	55	{ WM9713_ID2, 2, WM_READS(154), 154 },
	56	{ WM9713_ID2, 3, WM_READS(188), 188 },
4db8a5f2 MB	57	};
	58
	59	/* continuous speed index */
	60	static int sp_idx;
0ca7231f	61	static struct gpio_desc *gpiod_irq;
4db8a5f2 MB	62
	63	/*
	64	* Pen sampling frequency (Hz) in continuous mode.
	65	*/
	66	static int cont_rate = 200;
	67	module_param(cont_rate, int, 0);
	68	MODULE_PARM_DESC(cont_rate, "Sampling rate in continuous mode (Hz)");
	69
	70	/*
	71	* Pen down detection.
	72	*
	73	* This driver can either poll or use an interrupt to indicate a pen down
	74	* event. If the irq request fails then it will fall back to polling mode.
	75	*/
	76	static int pen_int;
	77	module_param(pen_int, int, 0);
	78	MODULE_PARM_DESC(pen_int, "Pen down detection (1 = interrupt, 0 = polling)");
	79
	80	/*
	81	* Pressure readback.
	82	*
	83	* Set to 1 to read back pen down pressure
	84	*/
	85	static int pressure;
	86	module_param(pressure, int, 0);
	87	MODULE_PARM_DESC(pressure, "Pressure readback (1 = pressure, 0 = no pressure)");
	88
	89	/*
	90	* AC97 touch data slot.
	91	*
	92	* Touch screen readback data ac97 slot
	93	*/
	94	static int ac97_touch_slot = 5;
	95	module_param(ac97_touch_slot, int, 0);
	96	MODULE_PARM_DESC(ac97_touch_slot, "Touch screen data slot AC97 number");
	97
	98
	99	/* flush AC97 slot 5 FIFO on pxa machines */
4db8a5f2 MB	100	static void wm97xx_acc_pen_up(struct wm97xx *wm)
4db8a5f2 MB	101	{
180deb50 JS	102	unsigned int count;
180deb50 JS	103
7b8a0b90	104	msleep(1);
4db8a5f2	105
bb628a6e	106	if (cpu_is_pxa27x()) {
e217b085 AB	107	while (pxa2xx_ac97_read_misr() & (1 << 2))
e217b085 AB	108	pxa2xx_ac97_read_modr();
bb628a6e AB	109	} else if (cpu_is_pxa3xx()) {
bb628a6e AB	110	for (count = 0; count < 16; count++)
e217b085	111	pxa2xx_ac97_read_modr();
bb628a6e	112	}
4db8a5f2	113	}
4db8a5f2 MB	114
	115	static int wm97xx_acc_pen_down(struct wm97xx *wm)
	116	{
	117	u16 x, y, p = 0x100 \| WM97XX_ADCSEL_PRES;
	118	int reads = 0;
7b8a0b90	119	static u16 last, tries;
4db8a5f2 MB	120
	121	/* When the AC97 queue has been drained we need to allow time
	122	* to buffer up samples otherwise we end up spinning polling
	123	* for samples. The controller can't have a suitably low
af901ca1	124	* threshold set to use the notifications it gives.
4db8a5f2	125	*/
7b8a0b90	126	msleep(1);
4db8a5f2 MB	127
	128	if (tries > 5) {
	129	tries = 0;
	130	return RC_PENUP;
	131	}
	132
e217b085	133	x = pxa2xx_ac97_read_modr();
4db8a5f2 MB	134	if (x == last) {
	135	tries++;
	136	return RC_AGAIN;
	137	}
	138	last = x;
	139	do {
	140	if (reads)
e217b085 AB	141	x = pxa2xx_ac97_read_modr();
e217b085 AB	142	y = pxa2xx_ac97_read_modr();
4db8a5f2	143	if (pressure)
e217b085	144	p = pxa2xx_ac97_read_modr();
4db8a5f2	145
dcfc32ba MB	146	dev_dbg(wm->dev, "Raw coordinates: x=%x, y=%x, p=%x\n",
	147	x, y, p);
	148
4db8a5f2	149	/* are samples valid */
2456689b WS	150	if ((x & WM97XX_ADCSEL_MASK) != WM97XX_ADCSEL_X \|\|
	151	(y & WM97XX_ADCSEL_MASK) != WM97XX_ADCSEL_Y \|\|
	152	(p & WM97XX_ADCSEL_MASK) != WM97XX_ADCSEL_PRES)
4db8a5f2 MB	153	goto up;
	154
	155	/* coordinate is good */
	156	tries = 0;
	157	input_report_abs(wm->input_dev, ABS_X, x & 0xfff);
	158	input_report_abs(wm->input_dev, ABS_Y, y & 0xfff);
	159	input_report_abs(wm->input_dev, ABS_PRESSURE, p & 0xfff);
cd2d64b1	160	input_report_key(wm->input_dev, BTN_TOUCH, (p != 0));
4db8a5f2 MB	161	input_sync(wm->input_dev);
	162	reads++;
	163	} while (reads < cinfo[sp_idx].reads);
	164	up:
	165	return RC_PENDOWN \| RC_AGAIN;
	166	}
	167
	168	static int wm97xx_acc_startup(struct wm97xx *wm)
	169	{
b833306f	170	int idx = 0, ret = 0;
4db8a5f2 MB	171
	172	/* check we have a codec */
	173	if (wm->ac97 == NULL)
	174	return -ENODEV;
	175
	176	/* Go you big red fire engine */
	177	for (idx = 0; idx < ARRAY_SIZE(cinfo); idx++) {
	178	if (wm->id != cinfo[idx].id)
	179	continue;
	180	sp_idx = idx;
	181	if (cont_rate <= cinfo[idx].speed)
	182	break;
	183	}
	184	wm->acc_rate = cinfo[sp_idx].code;
	185	wm->acc_slot = ac97_touch_slot;
	186	dev_info(wm->dev,
	187	"mainstone accelerated touchscreen driver, %d samples/sec\n",
	188	cinfo[sp_idx].speed);
	189
0ca7231f AB	190	if (pen_int) {
	191	gpiod_irq = gpiod_get(wm->dev, "touch", GPIOD_IN);
	192	if (IS_ERR(gpiod_irq))
	193	pen_int = 0;
	194	}
b833306f	195
0ca7231f AB	196	if (pen_int) {
0ca7231f AB	197	wm->pen_irq = gpiod_to_irq(gpiod_irq);
dced35ae	198	irq_set_irq_type(wm->pen_irq, IRQ_TYPE_EDGE_BOTH);
0ca7231f	199	}
b833306f	200
4db8a5f2 MB	201	/* codec specific irq config */
	202	if (pen_int) {
	203	switch (wm->id) {
	204	case WM9705_ID2:
4db8a5f2 MB	205	break;
	206	case WM9712_ID2:
	207	case WM9713_ID2:
4db8a5f2	208	/* use PEN_DOWN GPIO 13 to assert IRQ on GPIO line 2 */
4db8a5f2 MB	209	wm97xx_config_gpio(wm, WM97XX_GPIO_13, WM97XX_GPIO_IN,
	210	WM97XX_GPIO_POL_HIGH,
	211	WM97XX_GPIO_STICKY,
	212	WM97XX_GPIO_WAKE);
	213	wm97xx_config_gpio(wm, WM97XX_GPIO_2, WM97XX_GPIO_OUT,
	214	WM97XX_GPIO_POL_HIGH,
	215	WM97XX_GPIO_NOTSTICKY,
	216	WM97XX_GPIO_NOWAKE);
	217	break;
	218	default:
	219	dev_err(wm->dev,
	220	"pen down irq not supported on this device\n");
	221	pen_int = 0;
	222	break;
	223	}
	224	}
	225
b833306f	226	return ret;
4db8a5f2 MB	227	}
	228
	229	static void wm97xx_acc_shutdown(struct wm97xx *wm)
	230	{
	231	/* codec specific deconfig */
	232	if (pen_int) {
0ca7231f AB	233	if (gpiod_irq)
0ca7231f AB	234	gpiod_put(gpiod_irq);
b833306f	235	wm->pen_irq = 0;
4db8a5f2 MB	236	}
	237	}
	238
4db8a5f2	239	static struct wm97xx_mach_ops mainstone_mach_ops = {
7b8a0b90 AB	240	.acc_enabled = 1,
	241	.acc_pen_up = wm97xx_acc_pen_up,
	242	.acc_pen_down = wm97xx_acc_pen_down,
	243	.acc_startup = wm97xx_acc_startup,
	244	.acc_shutdown = wm97xx_acc_shutdown,
7b8a0b90	245	.irq_gpio = WM97XX_GPIO_2,
4db8a5f2 MB	246	};
	247
	248	static int mainstone_wm97xx_probe(struct platform_device *pdev)
	249	{
	250	struct wm97xx *wm = platform_get_drvdata(pdev);
	251
	252	return wm97xx_register_mach_ops(wm, &mainstone_mach_ops);
	253	}
	254
	255	static int mainstone_wm97xx_remove(struct platform_device *pdev)
	256	{
	257	struct wm97xx *wm = platform_get_drvdata(pdev);
	258
	259	wm97xx_unregister_mach_ops(wm);
7b8a0b90	260
4db8a5f2 MB	261	return 0;
	262	}
	263
	264	static struct platform_driver mainstone_wm97xx_driver = {
7b8a0b90 AB	265	.probe = mainstone_wm97xx_probe,
	266	.remove = mainstone_wm97xx_remove,
	267	.driver = {
	268	.name = "wm97xx-touch",
4db8a5f2 MB	269	},
4db8a5f2 MB	270	};
cdcc96e2	271	module_platform_driver(mainstone_wm97xx_driver);
4db8a5f2 MB	272
4db8a5f2 MB	273	/* Module information */
b8d055a8	274	MODULE_AUTHOR("Liam Girdwood <lrg@slimlogic.co.uk>");
4db8a5f2 MB	275	MODULE_DESCRIPTION("wm97xx continuous touch driver for mainstone");
4db8a5f2 MB	276	MODULE_LICENSE("GPL");