1 // SPDX-License-Identifier: GPL-2.0-only
3 * Driver for cypress touch screen controller
5 * Copyright (c) 2009 Aava Mobile
7 * Some cleanups by Alan Cox <alan@linux.intel.com>
10 #include <linux/i2c.h>
11 #include <linux/input.h>
12 #include <linux/interrupt.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/slab.h>
17 #include <asm/byteorder.h>
19 #define CY8CTMG110_DRIVER_NAME "cy8ctmg110"
21 /* Touch coordinates */
22 #define CY8CTMG110_X_MIN 0
23 #define CY8CTMG110_Y_MIN 0
24 #define CY8CTMG110_X_MAX 759
25 #define CY8CTMG110_Y_MAX 465
28 /* cy8ctmg110 register definitions */
29 #define CY8CTMG110_TOUCH_WAKEUP_TIME 0
30 #define CY8CTMG110_TOUCH_SLEEP_TIME 2
31 #define CY8CTMG110_TOUCH_X1 3
32 #define CY8CTMG110_TOUCH_Y1 5
33 #define CY8CTMG110_TOUCH_X2 7
34 #define CY8CTMG110_TOUCH_Y2 9
35 #define CY8CTMG110_FINGERS 11
36 #define CY8CTMG110_GESTURE 12
37 #define CY8CTMG110_REG_MAX 13
41 * The touch driver structure.
44 struct input_dev *input;
46 struct i2c_client *client;
47 struct gpio_desc *reset_gpio;
51 * cy8ctmg110_power is the routine that is called when touch hardware
52 * is being powered off or on. When powering on this routine de-asserts
53 * the RESET line, when powering off reset line is asserted.
55 static void cy8ctmg110_power(struct cy8ctmg110 *ts, bool poweron)
58 gpiod_set_value_cansleep(ts->reset_gpio, !poweron);
61 static int cy8ctmg110_write_regs(struct cy8ctmg110 *tsc, unsigned char reg,
62 unsigned char len, unsigned char *value)
64 struct i2c_client *client = tsc->client;
66 unsigned char i2c_data[6];
71 memcpy(i2c_data + 1, value, len);
73 ret = i2c_master_send(client, i2c_data, len + 1);
75 dev_err(&client->dev, "i2c write data cmd failed\n");
76 return ret < 0 ? ret : -EIO;
82 static int cy8ctmg110_read_regs(struct cy8ctmg110 *tsc,
83 unsigned char *data, unsigned char len, unsigned char cmd)
85 struct i2c_client *client = tsc->client;
87 struct i2c_msg msg[2] = {
88 /* first write slave position to i2c devices */
94 /* Second read data from position */
103 ret = i2c_transfer(client->adapter, msg, 2);
110 static int cy8ctmg110_touch_pos(struct cy8ctmg110 *tsc)
112 struct input_dev *input = tsc->input;
113 unsigned char reg_p[CY8CTMG110_REG_MAX];
115 memset(reg_p, 0, CY8CTMG110_REG_MAX);
117 /* Reading coordinates */
118 if (cy8ctmg110_read_regs(tsc, reg_p, 9, CY8CTMG110_TOUCH_X1) != 0)
121 /* Number of touch */
123 input_report_key(input, BTN_TOUCH, 0);
125 input_report_key(input, BTN_TOUCH, 1);
126 input_report_abs(input, ABS_X,
127 be16_to_cpup((__be16 *)(reg_p + 0)));
128 input_report_abs(input, ABS_Y,
129 be16_to_cpup((__be16 *)(reg_p + 2)));
137 static int cy8ctmg110_set_sleepmode(struct cy8ctmg110 *ts, bool sleep)
139 unsigned char reg_p[3];
151 return cy8ctmg110_write_regs(ts, CY8CTMG110_TOUCH_WAKEUP_TIME, 3, reg_p);
154 static irqreturn_t cy8ctmg110_irq_thread(int irq, void *dev_id)
156 struct cy8ctmg110 *tsc = dev_id;
158 cy8ctmg110_touch_pos(tsc);
163 static void cy8ctmg110_shut_off(void *_ts)
165 struct cy8ctmg110 *ts = _ts;
167 cy8ctmg110_set_sleepmode(ts, true);
168 cy8ctmg110_power(ts, false);
171 static int cy8ctmg110_probe(struct i2c_client *client,
172 const struct i2c_device_id *id)
174 struct cy8ctmg110 *ts;
175 struct input_dev *input_dev;
178 if (!i2c_check_functionality(client->adapter,
179 I2C_FUNC_SMBUS_READ_WORD_DATA))
182 ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
186 input_dev = devm_input_allocate_device(&client->dev);
191 ts->input = input_dev;
193 snprintf(ts->phys, sizeof(ts->phys),
194 "%s/input0", dev_name(&client->dev));
196 input_dev->name = CY8CTMG110_DRIVER_NAME " Touchscreen";
197 input_dev->phys = ts->phys;
198 input_dev->id.bustype = BUS_I2C;
200 input_set_capability(input_dev, EV_KEY, BTN_TOUCH);
201 input_set_abs_params(input_dev, ABS_X,
202 CY8CTMG110_X_MIN, CY8CTMG110_X_MAX, 4, 0);
203 input_set_abs_params(input_dev, ABS_Y,
204 CY8CTMG110_Y_MIN, CY8CTMG110_Y_MAX, 4, 0);
206 /* Request and assert reset line */
207 ts->reset_gpio = devm_gpiod_get_optional(&client->dev, NULL,
209 if (IS_ERR(ts->reset_gpio)) {
210 err = PTR_ERR(ts->reset_gpio);
211 dev_err(&client->dev,
212 "Unable to request reset GPIO: %d\n", err);
216 cy8ctmg110_power(ts, true);
217 cy8ctmg110_set_sleepmode(ts, false);
219 err = devm_add_action_or_reset(&client->dev, cy8ctmg110_shut_off, ts);
223 err = devm_request_threaded_irq(&client->dev, client->irq,
224 NULL, cy8ctmg110_irq_thread,
225 IRQF_ONESHOT, "touch_reset_key", ts);
227 dev_err(&client->dev,
228 "irq %d busy? error %d\n", client->irq, err);
232 err = input_register_device(input_dev);
236 i2c_set_clientdata(client, ts);
241 static int __maybe_unused cy8ctmg110_suspend(struct device *dev)
243 struct i2c_client *client = to_i2c_client(dev);
244 struct cy8ctmg110 *ts = i2c_get_clientdata(client);
246 if (!device_may_wakeup(&client->dev)) {
247 cy8ctmg110_set_sleepmode(ts, true);
248 cy8ctmg110_power(ts, false);
254 static int __maybe_unused cy8ctmg110_resume(struct device *dev)
256 struct i2c_client *client = to_i2c_client(dev);
257 struct cy8ctmg110 *ts = i2c_get_clientdata(client);
259 if (!device_may_wakeup(&client->dev)) {
260 cy8ctmg110_power(ts, true);
261 cy8ctmg110_set_sleepmode(ts, false);
267 static SIMPLE_DEV_PM_OPS(cy8ctmg110_pm, cy8ctmg110_suspend, cy8ctmg110_resume);
269 static const struct i2c_device_id cy8ctmg110_idtable[] = {
270 { CY8CTMG110_DRIVER_NAME, 1 },
274 MODULE_DEVICE_TABLE(i2c, cy8ctmg110_idtable);
276 static struct i2c_driver cy8ctmg110_driver = {
278 .name = CY8CTMG110_DRIVER_NAME,
279 .pm = &cy8ctmg110_pm,
281 .id_table = cy8ctmg110_idtable,
282 .probe = cy8ctmg110_probe,
285 module_i2c_driver(cy8ctmg110_driver);
287 MODULE_AUTHOR("Samuli Konttila <samuli.konttila@aavamobile.com>");
288 MODULE_DESCRIPTION("cy8ctmg110 TouchScreen Driver");
289 MODULE_LICENSE("GPL v2");