[deliverable/linux.git] / drivers / input / touchscreen / ts4800-ts.c

/*
 * Touchscreen driver for the TS-4800 board
 *
 * Copyright (c) 2015 - Savoir-faire Linux
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/bitops.h>
#include <linux/input.h>
#include <linux/input-polldev.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

/* polling interval in ms */
#define POLL_INTERVAL		3

#define DEBOUNCE_COUNT		1

/* sensor values are 12-bit wide */
#define MAX_12BIT		((1 << 12) - 1)

#define PENDOWN_MASK		0x1

#define X_OFFSET		0x0
#define Y_OFFSET		0x2

struct ts4800_ts {
	struct input_polled_dev *poll_dev;
	struct device           *dev;
	char                    phys[32];

	void __iomem            *base;
	struct regmap           *regmap;
	unsigned int            reg;
	unsigned int            bit;

	bool                    pendown;
	int                     debounce;
};

static void ts4800_ts_open(struct input_polled_dev *dev)
{
	struct ts4800_ts *ts = dev->private;
	int ret;

	ts->pendown = false;
	ts->debounce = DEBOUNCE_COUNT;

	ret = regmap_update_bits(ts->regmap, ts->reg, ts->bit, ts->bit);
	if (ret)
		dev_warn(ts->dev, "Failed to enable touchscreen\n");
}

static void ts4800_ts_close(struct input_polled_dev *dev)
{
	struct ts4800_ts *ts = dev->private;
	int ret;

	ret = regmap_update_bits(ts->regmap, ts->reg, ts->bit, 0);
	if (ret)
		dev_warn(ts->dev, "Failed to disable touchscreen\n");

}

static void ts4800_ts_poll(struct input_polled_dev *dev)
{
	struct input_dev *input_dev = dev->input;
	struct ts4800_ts *ts = dev->private;
	u16 last_x = readw(ts->base + X_OFFSET);
	u16 last_y = readw(ts->base + Y_OFFSET);
	bool pendown = last_x & PENDOWN_MASK;

	if (pendown) {
		if (ts->debounce) {
			ts->debounce--;
			return;
		}

		if (!ts->pendown) {
			input_report_key(input_dev, BTN_TOUCH, 1);
			ts->pendown = true;
		}

		last_x = ((~last_x) >> 4) & MAX_12BIT;
		last_y = ((~last_y) >> 4) & MAX_12BIT;

		input_report_abs(input_dev, ABS_X, last_x);
		input_report_abs(input_dev, ABS_Y, last_y);
		input_sync(input_dev);
	} else if (ts->pendown) {
		ts->pendown = false;
		ts->debounce = DEBOUNCE_COUNT;
		input_report_key(input_dev, BTN_TOUCH, 0);
		input_sync(input_dev);
	}
}

static int ts4800_parse_dt(struct platform_device *pdev,
			   struct ts4800_ts *ts)
{
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	struct device_node *syscon_np;
	u32 reg, bit;
	int error;

	syscon_np = of_parse_phandle(np, "syscon", 0);
	if (!syscon_np) {
		dev_err(dev, "no syscon property\n");
		return -ENODEV;
	}

	ts->regmap = syscon_node_to_regmap(syscon_np);
	of_node_put(syscon_np);
	if (IS_ERR(ts->regmap)) {
		dev_err(dev, "cannot get parent's regmap\n");
		return PTR_ERR(ts->regmap);
	}

	error = of_property_read_u32_index(np, "syscon", 1, &reg);
	if (error < 0) {
		dev_err(dev, "no offset in syscon\n");
		return error;
	}

	ts->reg = reg;

	error = of_property_read_u32_index(np, "syscon", 2, &bit);
	if (error < 0) {
		dev_err(dev, "no bit in syscon\n");
		return error;
	}

	ts->bit = BIT(bit);

	return 0;
}

static int ts4800_ts_probe(struct platform_device *pdev)
{
	struct input_polled_dev *poll_dev;
	struct ts4800_ts *ts;
	struct resource *res;
	int error;

	ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL);
	if (!ts)
		return -ENOMEM;

	error = ts4800_parse_dt(pdev, ts);
	if (error)
		return error;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	ts->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(ts->base))
		return PTR_ERR(ts->base);

	poll_dev = devm_input_allocate_polled_device(&pdev->dev);
	if (!poll_dev)
		return -ENOMEM;

	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&pdev->dev));
	ts->poll_dev = poll_dev;
	ts->dev = &pdev->dev;

	poll_dev->private = ts;
	poll_dev->poll_interval = POLL_INTERVAL;
	poll_dev->open = ts4800_ts_open;
	poll_dev->close = ts4800_ts_close;
	poll_dev->poll = ts4800_ts_poll;

	poll_dev->input->name = "TS-4800 Touchscreen";
	poll_dev->input->phys = ts->phys;

	input_set_capability(poll_dev->input, EV_KEY, BTN_TOUCH);
	input_set_abs_params(poll_dev->input, ABS_X, 0, MAX_12BIT, 0, 0);
	input_set_abs_params(poll_dev->input, ABS_Y, 0, MAX_12BIT, 0, 0);

	error = input_register_polled_device(poll_dev);
	if (error) {
		dev_err(&pdev->dev,
			"Unabled to register polled input device (%d)\n",
			error);
		return error;
	}

	return 0;
}

static const struct of_device_id ts4800_ts_of_match[] = {
	{ .compatible = "technologic,ts4800-ts", },
	{ },
};
MODULE_DEVICE_TABLE(of, ts4800_ts_of_match);

static struct platform_driver ts4800_ts_driver = {
	.driver = {
		.name = "ts4800-ts",
		.of_match_table = ts4800_ts_of_match,
	},
	.probe = ts4800_ts_probe,
};
module_platform_driver(ts4800_ts_driver);

MODULE_AUTHOR("Damien Riegel <damien.riegel@savoirfairelinux.com>");
MODULE_DESCRIPTION("TS-4800 Touchscreen Driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:ts4800_ts");
Commit	Line	Data
40e3be39 DR	1	/*
	2	* Touchscreen driver for the TS-4800 board
	3	*
	4	* Copyright (c) 2015 - Savoir-faire Linux
	5	*
	6	* This file is licensed under the terms of the GNU General Public
	7	* License version 2. This program is licensed "as is" without any
	8	* warranty of any kind, whether express or implied.
	9	*/
	10
	11	#include <linux/bitops.h>
	12	#include <linux/input.h>
	13	#include <linux/input-polldev.h>
	14	#include <linux/io.h>
	15	#include <linux/kernel.h>
	16	#include <linux/mfd/syscon.h>
	17	#include <linux/module.h>
	18	#include <linux/of.h>
	19	#include <linux/platform_device.h>
	20	#include <linux/regmap.h>
	21
	22	/* polling interval in ms */
	23	#define POLL_INTERVAL 3
	24
	25	#define DEBOUNCE_COUNT 1
	26
	27	/* sensor values are 12-bit wide */
	28	#define MAX_12BIT ((1 << 12) - 1)
	29
	30	#define PENDOWN_MASK 0x1
	31
	32	#define X_OFFSET 0x0
	33	#define Y_OFFSET 0x2
	34
	35	struct ts4800_ts {
	36	struct input_polled_dev *poll_dev;
	37	struct device *dev;
	38	char phys[32];
	39
	40	void __iomem *base;
	41	struct regmap *regmap;
	42	unsigned int reg;
	43	unsigned int bit;
	44
	45	bool pendown;
	46	int debounce;
	47	};
	48
	49	static void ts4800_ts_open(struct input_polled_dev *dev)
	50	{
	51	struct ts4800_ts *ts = dev->private;
	52	int ret;
	53
	54	ts->pendown = false;
	55	ts->debounce = DEBOUNCE_COUNT;
	56
	57	ret = regmap_update_bits(ts->regmap, ts->reg, ts->bit, ts->bit);
	58	if (ret)
	59	dev_warn(ts->dev, "Failed to enable touchscreen\n");
	60	}
	61
	62	static void ts4800_ts_close(struct input_polled_dev *dev)
	63	{
	64	struct ts4800_ts *ts = dev->private;
65	int ret;
66
67	ret = regmap_update_bits(ts->regmap, ts->reg, ts->bit, 0);
68	if (ret)
69	dev_warn(ts->dev, "Failed to disable touchscreen\n");
70
71	}
72
73	static void ts4800_ts_poll(struct input_polled_dev *dev)
74	{
75	struct input_dev *input_dev = dev->input;
76	struct ts4800_ts *ts = dev->private;
77	u16 last_x = readw(ts->base + X_OFFSET);
78	u16 last_y = readw(ts->base + Y_OFFSET);
79	bool pendown = last_x & PENDOWN_MASK;
80
81	if (pendown) {
82	if (ts->debounce) {
83	ts->debounce--;
84	return;
85	}
86
87	if (!ts->pendown) {
88	input_report_key(input_dev, BTN_TOUCH, 1);
89	ts->pendown = true;
90	}
91
92	last_x = ((~last_x) >> 4) & MAX_12BIT;
93	last_y = ((~last_y) >> 4) & MAX_12BIT;
94
95	input_report_abs(input_dev, ABS_X, last_x);
96	input_report_abs(input_dev, ABS_Y, last_y);
97	input_sync(input_dev);
98	} else if (ts->pendown) {
99	ts->pendown = false;
100	ts->debounce = DEBOUNCE_COUNT;
101	input_report_key(input_dev, BTN_TOUCH, 0);
102	input_sync(input_dev);
103	}
104	}
105
106	static int ts4800_parse_dt(struct platform_device *pdev,
107	struct ts4800_ts *ts)
108	{
109	struct device *dev = &pdev->dev;
110	struct device_node *np = dev->of_node;
111	struct device_node *syscon_np;
112	u32 reg, bit;
113	int error;
114
115	syscon_np = of_parse_phandle(np, "syscon", 0);
116	if (!syscon_np) {
117	dev_err(dev, "no syscon property\n");
118	return -ENODEV;
119	}
120
6a5029e6 PC	121	ts->regmap = syscon_node_to_regmap(syscon_np);
	122	of_node_put(syscon_np);
	123	if (IS_ERR(ts->regmap)) {
	124	dev_err(dev, "cannot get parent's regmap\n");
	125	return PTR_ERR(ts->regmap);
	126	}
	127
40e3be39 DR	128	error = of_property_read_u32_index(np, "syscon", 1, &reg);
	129	if (error < 0) {
	130	dev_err(dev, "no offset in syscon\n");
	131	return error;
	132	}
	133
	134	ts->reg = reg;
	135
	136	error = of_property_read_u32_index(np, "syscon", 2, &bit);
	137	if (error < 0) {
	138	dev_err(dev, "no bit in syscon\n");
	139	return error;
	140	}
	141
	142	ts->bit = BIT(bit);
	143
40e3be39 DR	144	return 0;
	145	}
	146
	147	static int ts4800_ts_probe(struct platform_device *pdev)
	148	{
	149	struct input_polled_dev *poll_dev;
	150	struct ts4800_ts *ts;
	151	struct resource *res;
	152	int error;
	153
	154	ts = devm_kzalloc(&pdev->dev, sizeof(*ts), GFP_KERNEL);
	155	if (!ts)
	156	return -ENOMEM;
	157
	158	error = ts4800_parse_dt(pdev, ts);
	159	if (error)
	160	return error;
	161
	162	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	163	ts->base = devm_ioremap_resource(&pdev->dev, res);
	164	if (IS_ERR(ts->base))
	165	return PTR_ERR(ts->base);
	166
	167	poll_dev = devm_input_allocate_polled_device(&pdev->dev);
	168	if (!poll_dev)
	169	return -ENOMEM;
	170
	171	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&pdev->dev));
	172	ts->poll_dev = poll_dev;
	173	ts->dev = &pdev->dev;
	174
	175	poll_dev->private = ts;
	176	poll_dev->poll_interval = POLL_INTERVAL;
	177	poll_dev->open = ts4800_ts_open;
	178	poll_dev->close = ts4800_ts_close;
	179	poll_dev->poll = ts4800_ts_poll;
	180
	181	poll_dev->input->name = "TS-4800 Touchscreen";
	182	poll_dev->input->phys = ts->phys;
	183
	184	input_set_capability(poll_dev->input, EV_KEY, BTN_TOUCH);
	185	input_set_abs_params(poll_dev->input, ABS_X, 0, MAX_12BIT, 0, 0);
	186	input_set_abs_params(poll_dev->input, ABS_Y, 0, MAX_12BIT, 0, 0);
	187
	188	error = input_register_polled_device(poll_dev);
	189	if (error) {
	190	dev_err(&pdev->dev,
	191	"Unabled to register polled input device (%d)\n",
	192	error);
	193	return error;
	194	}
	195
	196	return 0;
	197	}
	198
	199	static const struct of_device_id ts4800_ts_of_match[] = {
	200	{ .compatible = "technologic,ts4800-ts", },
	201	{ },
	202	};
	203	MODULE_DEVICE_TABLE(of, ts4800_ts_of_match);
	204
	205	static struct platform_driver ts4800_ts_driver = {
	206	.driver = {
	207	.name = "ts4800-ts",
208	.of_match_table = ts4800_ts_of_match,
209	},
210	.probe = ts4800_ts_probe,
211	};
212	module_platform_driver(ts4800_ts_driver);
213
214	MODULE_AUTHOR("Damien Riegel <damien.riegel@savoirfairelinux.com>");
215	MODULE_DESCRIPTION("TS-4800 Touchscreen Driver");
216	MODULE_LICENSE("GPL v2");
217	MODULE_ALIAS("platform:ts4800_ts");