1/*
2 * Touchscreen driver for Marvell 88PM860x
3 *
4 * Copyright (C) 2009 Marvell International Ltd.
5 * 	Haojian Zhuang <haojian.zhuang@marvell.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/i2c.h>
16#include <linux/input.h>
17#include <linux/mfd/88pm860x.h>
18#include <linux/slab.h>
19#include <linux/device.h>
20
21#define MEAS_LEN		(8)
22#define ACCURATE_BIT		(12)
23
24/* touch register */
25#define MEAS_EN3		(0x52)
26
27#define MEAS_TSIX_1		(0x8D)
28#define MEAS_TSIX_2		(0x8E)
29#define MEAS_TSIY_1		(0x8F)
30#define MEAS_TSIY_2		(0x90)
31#define MEAS_TSIZ1_1		(0x91)
32#define MEAS_TSIZ1_2		(0x92)
33#define MEAS_TSIZ2_1		(0x93)
34#define MEAS_TSIZ2_2		(0x94)
35
36/* bit definitions of touch */
37#define MEAS_PD_EN		(1 << 3)
38#define MEAS_TSIX_EN		(1 << 4)
39#define MEAS_TSIY_EN		(1 << 5)
40#define MEAS_TSIZ1_EN		(1 << 6)
41#define MEAS_TSIZ2_EN		(1 << 7)
42
43struct pm860x_touch {
44	struct input_dev *idev;
45	struct i2c_client *i2c;
46	struct pm860x_chip *chip;
47	int irq;
48	int res_x;		/* resistor of Xplate */
49};
50
51static irqreturn_t pm860x_touch_handler(int irq, void *data)
52{
53	struct pm860x_touch *touch = data;
54	struct pm860x_chip *chip = touch->chip;
55	unsigned char buf[MEAS_LEN];
56	int x, y, pen_down;
57	int z1, z2, rt = 0;
58	int ret;
59
60	ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
61	if (ret < 0)
62		goto out;
63
64	pen_down = buf[1] & (1 << 6);
65	x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
66	y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
67	z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
68	z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
69
70	if (pen_down) {
71		if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
72			rt = z2 / z1 - 1;
73			rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
74			dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
75				z1, z2, rt);
76		}
77		input_report_abs(touch->idev, ABS_X, x);
78		input_report_abs(touch->idev, ABS_Y, y);
79		input_report_abs(touch->idev, ABS_PRESSURE, rt);
80		input_report_key(touch->idev, BTN_TOUCH, 1);
81		dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
82	} else {
83		input_report_abs(touch->idev, ABS_PRESSURE, 0);
84		input_report_key(touch->idev, BTN_TOUCH, 0);
85		dev_dbg(chip->dev, "pen release\n");
86	}
87	input_sync(touch->idev);
88
89out:
90	return IRQ_HANDLED;
91}
92
93static int pm860x_touch_open(struct input_dev *dev)
94{
95	struct pm860x_touch *touch = input_get_drvdata(dev);
96	int data, ret;
97
98	data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
99		| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
100	ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
101	if (ret < 0)
102		goto out;
103	return 0;
104out:
105	return ret;
106}
107
108static void pm860x_touch_close(struct input_dev *dev)
109{
110	struct pm860x_touch *touch = input_get_drvdata(dev);
111	int data;
112
113	data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
114		| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
115	pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
116}
117
118#ifdef CONFIG_OF
119static int pm860x_touch_dt_init(struct platform_device *pdev,
120					  struct pm860x_chip *chip,
121					  int *res_x)
122{
123	struct device_node *np = pdev->dev.parent->of_node;
124	struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
125				 : chip->companion;
126	int data, n, ret;
127	if (!np)
128		return -ENODEV;
129	np = of_find_node_by_name(np, "touch");
130	if (!np) {
131		dev_err(&pdev->dev, "Can't find touch node\n");
132		return -EINVAL;
133	}
134	/* set GPADC MISC1 register */
135	data = 0;
136	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
137		data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
138	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
139		data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
140	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
141		data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
142	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
143		data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
144	if (data) {
145		ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
146		if (ret < 0)
147			return -EINVAL;
148	}
149	/* set tsi prebias time */
150	if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
151		ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
152		if (ret < 0)
153			return -EINVAL;
154	}
155	/* set prebias & prechg time of pen detect */
156	data = 0;
157	if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
158		data |= n & PM8607_PD_PREBIAS_MASK;
159	if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
160		data |= n & PM8607_PD_PRECHG_MASK;
161	if (data) {
162		ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
163		if (ret < 0)
164			return -EINVAL;
165	}
166	of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
167	return 0;
168}
169#else
170#define pm860x_touch_dt_init(x, y, z)	(-1)
171#endif
172
173static int pm860x_touch_probe(struct platform_device *pdev)
174{
175	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
176	struct pm860x_touch_pdata *pdata = dev_get_platdata(&pdev->dev);
177	struct pm860x_touch *touch;
178	struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
179				 : chip->companion;
180	int irq, ret, res_x = 0, data = 0;
181
182	irq = platform_get_irq(pdev, 0);
183	if (irq < 0) {
184		dev_err(&pdev->dev, "No IRQ resource!\n");
185		return -EINVAL;
186	}
187
188	if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
189		if (pdata) {
190			/* set GPADC MISC1 register */
191			data = 0;
192			data |= (pdata->gpadc_prebias << 1)
193				& PM8607_GPADC_PREBIAS_MASK;
194			data |= (pdata->slot_cycle << 3)
195				& PM8607_GPADC_SLOT_CYCLE_MASK;
196			data |= (pdata->off_scale << 5)
197				& PM8607_GPADC_OFF_SCALE_MASK;
198			data |= (pdata->sw_cal << 7)
199				& PM8607_GPADC_SW_CAL_MASK;
200			if (data) {
201				ret = pm860x_reg_write(i2c,
202					PM8607_GPADC_MISC1, data);
203				if (ret < 0)
204					return -EINVAL;
205			}
206			/* set tsi prebias time */
207			if (pdata->tsi_prebias) {
208				data = pdata->tsi_prebias;
209				ret = pm860x_reg_write(i2c,
210					PM8607_TSI_PREBIAS, data);
211				if (ret < 0)
212					return -EINVAL;
213			}
214			/* set prebias & prechg time of pen detect */
215			data = 0;
216			data |= pdata->pen_prebias
217				& PM8607_PD_PREBIAS_MASK;
218			data |= (pdata->pen_prechg << 5)
219				& PM8607_PD_PRECHG_MASK;
220			if (data) {
221				ret = pm860x_reg_write(i2c,
222					PM8607_PD_PREBIAS, data);
223				if (ret < 0)
224					return -EINVAL;
225			}
226			res_x = pdata->res_x;
227		} else {
228			dev_err(&pdev->dev, "failed to get platform data\n");
229			return -EINVAL;
230		}
231	}
232	/* enable GPADC */
233	ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
234			      PM8607_GPADC_EN);
235	if (ret)
236		return ret;
237
238	touch = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_touch),
239			     GFP_KERNEL);
240	if (!touch)
241		return -ENOMEM;
242
243	platform_set_drvdata(pdev, touch);
244
245	touch->idev = devm_input_allocate_device(&pdev->dev);
246	if (!touch->idev) {
247		dev_err(&pdev->dev, "Failed to allocate input device!\n");
248		return -ENOMEM;
249	}
250
251	touch->idev->name = "88pm860x-touch";
252	touch->idev->phys = "88pm860x/input0";
253	touch->idev->id.bustype = BUS_I2C;
254	touch->idev->dev.parent = &pdev->dev;
255	touch->idev->open = pm860x_touch_open;
256	touch->idev->close = pm860x_touch_close;
257	touch->chip = chip;
258	touch->i2c = i2c;
259	touch->irq = irq;
260	touch->res_x = res_x;
261	input_set_drvdata(touch->idev, touch);
262
263	ret = devm_request_threaded_irq(&pdev->dev, touch->irq, NULL,
264					pm860x_touch_handler, IRQF_ONESHOT,
265					"touch", touch);
266	if (ret < 0)
267		return ret;
268
269	__set_bit(EV_ABS, touch->idev->evbit);
270	__set_bit(ABS_X, touch->idev->absbit);
271	__set_bit(ABS_Y, touch->idev->absbit);
272	__set_bit(ABS_PRESSURE, touch->idev->absbit);
273	__set_bit(EV_SYN, touch->idev->evbit);
274	__set_bit(EV_KEY, touch->idev->evbit);
275	__set_bit(BTN_TOUCH, touch->idev->keybit);
276
277	input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
278	input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
279	input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
280				0, 0);
281
282	ret = input_register_device(touch->idev);
283	if (ret < 0) {
284		dev_err(chip->dev, "Failed to register touch!\n");
285		return ret;
286	}
287
288	platform_set_drvdata(pdev, touch);
289	return 0;
290}
291
292static struct platform_driver pm860x_touch_driver = {
293	.driver	= {
294		.name	= "88pm860x-touch",
295		.owner	= THIS_MODULE,
296	},
297	.probe	= pm860x_touch_probe,
298};
299module_platform_driver(pm860x_touch_driver);
300
301MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
302MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
303MODULE_LICENSE("GPL");
304MODULE_ALIAS("platform:88pm860x-touch");
305
306