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
pm860x_touch_handler(int irq,void * data)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
pm860x_touch_open(struct input_dev * dev)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
pm860x_touch_close(struct input_dev * dev)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
pm860x_touch_dt_init(struct platform_device * pdev,struct pm860x_chip * chip,int * res_x)116 static 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
169 err_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
pm860x_touch_probe(struct platform_device * pdev)178 static 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
292 static struct platform_driver pm860x_touch_driver = {
293 .driver = {
294 .name = "88pm860x-touch",
295 },
296 .probe = pm860x_touch_probe,
297 };
298 module_platform_driver(pm860x_touch_driver);
299
300 MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
301 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
302 MODULE_LICENSE("GPL");
303 MODULE_ALIAS("platform:88pm860x-touch");
304
305