1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Touchscreen driver for Marvell 88PM860x
4 *
5 * Copyright (C) 2009 Marvell International Ltd.
6 * 	Haojian Zhuang <haojian.zhuang@marvell.com>
7 */
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/of.h>
11#include <linux/platform_device.h>
12#include <linux/i2c.h>
13#include <linux/input.h>
14#include <linux/mfd/88pm860x.h>
15#include <linux/slab.h>
16#include <linux/device.h>
17
18#define MEAS_LEN		(8)
19#define ACCURATE_BIT		(12)
20
21/* touch register */
22#define MEAS_EN3		(0x52)
23
24#define MEAS_TSIX_1		(0x8D)
25#define MEAS_TSIX_2		(0x8E)
26#define MEAS_TSIY_1		(0x8F)
27#define MEAS_TSIY_2		(0x90)
28#define MEAS_TSIZ1_1		(0x91)
29#define MEAS_TSIZ1_2		(0x92)
30#define MEAS_TSIZ2_1		(0x93)
31#define MEAS_TSIZ2_2		(0x94)
32
33/* bit definitions of touch */
34#define MEAS_PD_EN		(1 << 3)
35#define MEAS_TSIX_EN		(1 << 4)
36#define MEAS_TSIY_EN		(1 << 5)
37#define MEAS_TSIZ1_EN		(1 << 6)
38#define MEAS_TSIZ2_EN		(1 << 7)
39
40struct pm860x_touch {
41	struct input_dev *idev;
42	struct i2c_client *i2c;
43	struct pm860x_chip *chip;
44	int irq;
45	int res_x;		/* resistor of Xplate */
46};
47
48static irqreturn_t pm860x_touch_handler(int irq, void *data)
49{
50	struct pm860x_touch *touch = data;
51	struct pm860x_chip *chip = touch->chip;
52	unsigned char buf[MEAS_LEN];
53	int x, y, pen_down;
54	int z1, z2, rt = 0;
55	int ret;
56
57	ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
58	if (ret < 0)
59		goto out;
60
61	pen_down = buf[1] & (1 << 6);
62	x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
63	y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
64	z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
65	z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
66
67	if (pen_down) {
68		if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
69			rt = z2 / z1 - 1;
70			rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
71			dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
72				z1, z2, rt);
73		}
74		input_report_abs(touch->idev, ABS_X, x);
75		input_report_abs(touch->idev, ABS_Y, y);
76		input_report_abs(touch->idev, ABS_PRESSURE, rt);
77		input_report_key(touch->idev, BTN_TOUCH, 1);
78		dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
79	} else {
80		input_report_abs(touch->idev, ABS_PRESSURE, 0);
81		input_report_key(touch->idev, BTN_TOUCH, 0);
82		dev_dbg(chip->dev, "pen release\n");
83	}
84	input_sync(touch->idev);
85
86out:
87	return IRQ_HANDLED;
88}
89
90static int pm860x_touch_open(struct input_dev *dev)
91{
92	struct pm860x_touch *touch = input_get_drvdata(dev);
93	int data, ret;
94
95	data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
96		| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
97	ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
98	if (ret < 0)
99		goto out;
100	return 0;
101out:
102	return ret;
103}
104
105static void pm860x_touch_close(struct input_dev *dev)
106{
107	struct pm860x_touch *touch = input_get_drvdata(dev);
108	int data;
109
110	data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
111		| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
112	pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
113}
114
115#ifdef CONFIG_OF
116static int pm860x_touch_dt_init(struct platform_device *pdev,
117					  struct pm860x_chip *chip,
118					  int *res_x)
119{
120	struct device_node *np = pdev->dev.parent->of_node;
121	struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
122				 : chip->companion;
123	int data, n, ret;
124	if (!np)
125		return -ENODEV;
126	np = of_get_child_by_name(np, "touch");
127	if (!np) {
128		dev_err(&pdev->dev, "Can't find touch node\n");
129		return -EINVAL;
130	}
131	/* set GPADC MISC1 register */
132	data = 0;
133	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
134		data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
135	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
136		data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
137	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
138		data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
139	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
140		data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
141	if (data) {
142		ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
143		if (ret < 0)
144			goto err_put_node;
145	}
146	/* set tsi prebias time */
147	if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
148		ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
149		if (ret < 0)
150			goto err_put_node;
151	}
152	/* set prebias & prechg time of pen detect */
153	data = 0;
154	if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
155		data |= n & PM8607_PD_PREBIAS_MASK;
156	if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
157		data |= n & PM8607_PD_PRECHG_MASK;
158	if (data) {
159		ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
160		if (ret < 0)
161			goto err_put_node;
162	}
163	of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
164
165	of_node_put(np);
166
167	return 0;
168
169err_put_node:
170	of_node_put(np);
171
172	return -EINVAL;
173}
174#else
175#define pm860x_touch_dt_init(x, y, z)	(-1)
176#endif
177
178static int pm860x_touch_probe(struct platform_device *pdev)
179{
180	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
181	struct pm860x_touch_pdata *pdata = dev_get_platdata(&pdev->dev);
182	struct pm860x_touch *touch;
183	struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
184				 : chip->companion;
185	int irq, ret, res_x = 0, data = 0;
186
187	irq = platform_get_irq(pdev, 0);
188	if (irq < 0)
189		return -EINVAL;
190
191	if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
192		if (pdata) {
193			/* set GPADC MISC1 register */
194			data = 0;
195			data |= (pdata->gpadc_prebias << 1)
196				& PM8607_GPADC_PREBIAS_MASK;
197			data |= (pdata->slot_cycle << 3)
198				& PM8607_GPADC_SLOT_CYCLE_MASK;
199			data |= (pdata->off_scale << 5)
200				& PM8607_GPADC_OFF_SCALE_MASK;
201			data |= (pdata->sw_cal << 7)
202				& PM8607_GPADC_SW_CAL_MASK;
203			if (data) {
204				ret = pm860x_reg_write(i2c,
205					PM8607_GPADC_MISC1, data);
206				if (ret < 0)
207					return -EINVAL;
208			}
209			/* set tsi prebias time */
210			if (pdata->tsi_prebias) {
211				data = pdata->tsi_prebias;
212				ret = pm860x_reg_write(i2c,
213					PM8607_TSI_PREBIAS, data);
214				if (ret < 0)
215					return -EINVAL;
216			}
217			/* set prebias & prechg time of pen detect */
218			data = 0;
219			data |= pdata->pen_prebias
220				& PM8607_PD_PREBIAS_MASK;
221			data |= (pdata->pen_prechg << 5)
222				& PM8607_PD_PRECHG_MASK;
223			if (data) {
224				ret = pm860x_reg_write(i2c,
225					PM8607_PD_PREBIAS, data);
226				if (ret < 0)
227					return -EINVAL;
228			}
229			res_x = pdata->res_x;
230		} else {
231			dev_err(&pdev->dev, "failed to get platform data\n");
232			return -EINVAL;
233		}
234	}
235	/* enable GPADC */
236	ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
237			      PM8607_GPADC_EN);
238	if (ret)
239		return ret;
240
241	touch = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_touch),
242			     GFP_KERNEL);
243	if (!touch)
244		return -ENOMEM;
245
246	touch->idev = devm_input_allocate_device(&pdev->dev);
247	if (!touch->idev) {
248		dev_err(&pdev->dev, "Failed to allocate input device!\n");
249		return -ENOMEM;
250	}
251
252	touch->idev->name = "88pm860x-touch";
253	touch->idev->phys = "88pm860x/input0";
254	touch->idev->id.bustype = BUS_I2C;
255	touch->idev->dev.parent = &pdev->dev;
256	touch->idev->open = pm860x_touch_open;
257	touch->idev->close = pm860x_touch_close;
258	touch->chip = chip;
259	touch->i2c = i2c;
260	touch->irq = irq;
261	touch->res_x = res_x;
262	input_set_drvdata(touch->idev, touch);
263
264	ret = devm_request_threaded_irq(&pdev->dev, touch->irq, NULL,
265					pm860x_touch_handler, IRQF_ONESHOT,
266					"touch", touch);
267	if (ret < 0)
268		return ret;
269
270	__set_bit(EV_ABS, touch->idev->evbit);
271	__set_bit(ABS_X, touch->idev->absbit);
272	__set_bit(ABS_Y, touch->idev->absbit);
273	__set_bit(ABS_PRESSURE, touch->idev->absbit);
274	__set_bit(EV_SYN, touch->idev->evbit);
275	__set_bit(EV_KEY, touch->idev->evbit);
276	__set_bit(BTN_TOUCH, touch->idev->keybit);
277
278	input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
279	input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
280	input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
281				0, 0);
282
283	ret = input_register_device(touch->idev);
284	if (ret < 0) {
285		dev_err(chip->dev, "Failed to register touch!\n");
286		return ret;
287	}
288
289	return 0;
290}
291
292static struct platform_driver pm860x_touch_driver = {
293	.driver	= {
294		.name	= "88pm860x-touch",
295	},
296	.probe	= pm860x_touch_probe,
297};
298module_platform_driver(pm860x_touch_driver);
299
300MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
301MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
302MODULE_LICENSE("GPL");
303MODULE_ALIAS("platform:88pm860x-touch");
304
305