xref: /linux/drivers/input/touchscreen/88pm860x-ts.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 
40 struct 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 
48 static 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 
86 out:
87 	return IRQ_HANDLED;
88 }
89 
90 static 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;
101 out:
102 	return ret;
103 }
104 
105 static 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
116 static int pm860x_touch_dt_init(struct platform_device *pdev,
117 					  struct pm860x_chip *chip,
118 					  int *res_x)
119 {
120 	struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
121 				 : chip->companion;
122 	int data, n, ret;
123 	if (!pdev->dev.parent->of_node)
124 		return -ENODEV;
125 
126 	struct device_node *np __free(device_node) =
127 		of_get_child_by_name(pdev->dev.parent->of_node, "touch");
128 	if (!np) {
129 		dev_err(&pdev->dev, "Can't find touch node\n");
130 		return -EINVAL;
131 	}
132 	/* set GPADC MISC1 register */
133 	data = 0;
134 	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
135 		data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
136 	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
137 		data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
138 	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
139 		data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
140 	if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
141 		data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
142 	if (data) {
143 		ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
144 		if (ret < 0)
145 			return -EINVAL;
146 	}
147 	/* set tsi prebias time */
148 	if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
149 		ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
150 		if (ret < 0)
151 			return -EINVAL;
152 	}
153 	/* set prebias & prechg time of pen detect */
154 	data = 0;
155 	if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
156 		data |= n & PM8607_PD_PREBIAS_MASK;
157 	if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
158 		data |= n & PM8607_PD_PRECHG_MASK;
159 	if (data) {
160 		ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
161 		if (ret < 0)
162 			return -EINVAL;
163 	}
164 	of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
165 
166 	return 0;
167 }
168 #else
169 #define pm860x_touch_dt_init(x, y, z)	(-1)
170 #endif
171 
172 static int pm860x_touch_probe(struct platform_device *pdev)
173 {
174 	struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
175 	struct pm860x_touch_pdata *pdata = dev_get_platdata(&pdev->dev);
176 	struct pm860x_touch *touch;
177 	struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
178 				 : chip->companion;
179 	int irq, ret, res_x = 0, data = 0;
180 
181 	irq = platform_get_irq(pdev, 0);
182 	if (irq < 0)
183 		return -EINVAL;
184 
185 	if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
186 		if (pdata) {
187 			/* set GPADC MISC1 register */
188 			data = 0;
189 			data |= (pdata->gpadc_prebias << 1)
190 				& PM8607_GPADC_PREBIAS_MASK;
191 			data |= (pdata->slot_cycle << 3)
192 				& PM8607_GPADC_SLOT_CYCLE_MASK;
193 			data |= (pdata->off_scale << 5)
194 				& PM8607_GPADC_OFF_SCALE_MASK;
195 			data |= (pdata->sw_cal << 7)
196 				& PM8607_GPADC_SW_CAL_MASK;
197 			if (data) {
198 				ret = pm860x_reg_write(i2c,
199 					PM8607_GPADC_MISC1, data);
200 				if (ret < 0)
201 					return -EINVAL;
202 			}
203 			/* set tsi prebias time */
204 			if (pdata->tsi_prebias) {
205 				data = pdata->tsi_prebias;
206 				ret = pm860x_reg_write(i2c,
207 					PM8607_TSI_PREBIAS, data);
208 				if (ret < 0)
209 					return -EINVAL;
210 			}
211 			/* set prebias & prechg time of pen detect */
212 			data = 0;
213 			data |= pdata->pen_prebias
214 				& PM8607_PD_PREBIAS_MASK;
215 			data |= (pdata->pen_prechg << 5)
216 				& PM8607_PD_PRECHG_MASK;
217 			if (data) {
218 				ret = pm860x_reg_write(i2c,
219 					PM8607_PD_PREBIAS, data);
220 				if (ret < 0)
221 					return -EINVAL;
222 			}
223 			res_x = pdata->res_x;
224 		} else {
225 			dev_err(&pdev->dev, "failed to get platform data\n");
226 			return -EINVAL;
227 		}
228 	}
229 	/* enable GPADC */
230 	ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
231 			      PM8607_GPADC_EN);
232 	if (ret)
233 		return ret;
234 
235 	touch = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_touch),
236 			     GFP_KERNEL);
237 	if (!touch)
238 		return -ENOMEM;
239 
240 	touch->idev = devm_input_allocate_device(&pdev->dev);
241 	if (!touch->idev) {
242 		dev_err(&pdev->dev, "Failed to allocate input device!\n");
243 		return -ENOMEM;
244 	}
245 
246 	touch->idev->name = "88pm860x-touch";
247 	touch->idev->phys = "88pm860x/input0";
248 	touch->idev->id.bustype = BUS_I2C;
249 	touch->idev->dev.parent = &pdev->dev;
250 	touch->idev->open = pm860x_touch_open;
251 	touch->idev->close = pm860x_touch_close;
252 	touch->chip = chip;
253 	touch->i2c = i2c;
254 	touch->irq = irq;
255 	touch->res_x = res_x;
256 	input_set_drvdata(touch->idev, touch);
257 
258 	ret = devm_request_threaded_irq(&pdev->dev, touch->irq, NULL,
259 					pm860x_touch_handler, IRQF_ONESHOT,
260 					"touch", touch);
261 	if (ret < 0)
262 		return ret;
263 
264 	__set_bit(EV_ABS, touch->idev->evbit);
265 	__set_bit(ABS_X, touch->idev->absbit);
266 	__set_bit(ABS_Y, touch->idev->absbit);
267 	__set_bit(ABS_PRESSURE, touch->idev->absbit);
268 	__set_bit(EV_SYN, touch->idev->evbit);
269 	__set_bit(EV_KEY, touch->idev->evbit);
270 	__set_bit(BTN_TOUCH, touch->idev->keybit);
271 
272 	input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
273 	input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
274 	input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
275 				0, 0);
276 
277 	ret = input_register_device(touch->idev);
278 	if (ret < 0) {
279 		dev_err(chip->dev, "Failed to register touch!\n");
280 		return ret;
281 	}
282 
283 	return 0;
284 }
285 
286 static struct platform_driver pm860x_touch_driver = {
287 	.driver	= {
288 		.name	= "88pm860x-touch",
289 	},
290 	.probe	= pm860x_touch_probe,
291 };
292 module_platform_driver(pm860x_touch_driver);
293 
294 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
295 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
296 MODULE_LICENSE("GPL");
297 MODULE_ALIAS("platform:88pm860x-touch");
298 
299