1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Driver for cypress touch screen controller
4 *
5 * Copyright (c) 2009 Aava Mobile
6 *
7 * Some cleanups by Alan Cox <alan@linux.intel.com>
8 */
9
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>
18
19#define CY8CTMG110_DRIVER_NAME "cy8ctmg110"
20
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
26
27
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
38
39
40/*
41 * The touch driver structure.
42 */
43struct cy8ctmg110 {
44 struct input_dev *input;
45 char phys[32];
46 struct i2c_client *client;
47 struct gpio_desc *reset_gpio;
48};
49
50/*
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.
54 */
55static void cy8ctmg110_power(struct cy8ctmg110 *ts, bool poweron)
56{
57 if (ts->reset_gpio)
58 gpiod_set_value_cansleep(desc: ts->reset_gpio, value: !poweron);
59}
60
61static int cy8ctmg110_write_regs(struct cy8ctmg110 *tsc, unsigned char reg,
62 unsigned char len, unsigned char *value)
63{
64 struct i2c_client *client = tsc->client;
65 int ret;
66 unsigned char i2c_data[6];
67
68 BUG_ON(len > 5);
69
70 i2c_data[0] = reg;
71 memcpy(i2c_data + 1, value, len);
72
73 ret = i2c_master_send(client, buf: i2c_data, count: len + 1);
74 if (ret != len + 1) {
75 dev_err(&client->dev, "i2c write data cmd failed\n");
76 return ret < 0 ? ret : -EIO;
77 }
78
79 return 0;
80}
81
82static int cy8ctmg110_read_regs(struct cy8ctmg110 *tsc,
83 unsigned char *data, unsigned char len, unsigned char cmd)
84{
85 struct i2c_client *client = tsc->client;
86 int ret;
87 struct i2c_msg msg[2] = {
88 /* first write slave position to i2c devices */
89 {
90 .addr = client->addr,
91 .len = 1,
92 .buf = &cmd
93 },
94 /* Second read data from position */
95 {
96 .addr = client->addr,
97 .flags = I2C_M_RD,
98 .len = len,
99 .buf = data
100 }
101 };
102
103 ret = i2c_transfer(adap: client->adapter, msgs: msg, num: 2);
104 if (ret < 0)
105 return ret;
106
107 return 0;
108}
109
110static int cy8ctmg110_touch_pos(struct cy8ctmg110 *tsc)
111{
112 struct input_dev *input = tsc->input;
113 unsigned char reg_p[CY8CTMG110_REG_MAX];
114
115 memset(reg_p, 0, CY8CTMG110_REG_MAX);
116
117 /* Reading coordinates */
118 if (cy8ctmg110_read_regs(tsc, data: reg_p, len: 9, CY8CTMG110_TOUCH_X1) != 0)
119 return -EIO;
120
121 /* Number of touch */
122 if (reg_p[8] == 0) {
123 input_report_key(dev: input, BTN_TOUCH, value: 0);
124 } else {
125 input_report_key(dev: input, BTN_TOUCH, value: 1);
126 input_report_abs(dev: input, ABS_X,
127 be16_to_cpup(p: (__be16 *)(reg_p + 0)));
128 input_report_abs(dev: input, ABS_Y,
129 be16_to_cpup(p: (__be16 *)(reg_p + 2)));
130 }
131
132 input_sync(dev: input);
133
134 return 0;
135}
136
137static int cy8ctmg110_set_sleepmode(struct cy8ctmg110 *ts, bool sleep)
138{
139 unsigned char reg_p[3];
140
141 if (sleep) {
142 reg_p[0] = 0x00;
143 reg_p[1] = 0xff;
144 reg_p[2] = 5;
145 } else {
146 reg_p[0] = 0x10;
147 reg_p[1] = 0xff;
148 reg_p[2] = 0;
149 }
150
151 return cy8ctmg110_write_regs(tsc: ts, CY8CTMG110_TOUCH_WAKEUP_TIME, len: 3, value: reg_p);
152}
153
154static irqreturn_t cy8ctmg110_irq_thread(int irq, void *dev_id)
155{
156 struct cy8ctmg110 *tsc = dev_id;
157
158 cy8ctmg110_touch_pos(tsc);
159
160 return IRQ_HANDLED;
161}
162
163static void cy8ctmg110_shut_off(void *_ts)
164{
165 struct cy8ctmg110 *ts = _ts;
166
167 cy8ctmg110_set_sleepmode(ts, sleep: true);
168 cy8ctmg110_power(ts, poweron: false);
169}
170
171static int cy8ctmg110_probe(struct i2c_client *client)
172{
173 struct cy8ctmg110 *ts;
174 struct input_dev *input_dev;
175 int err;
176
177 if (!i2c_check_functionality(adap: client->adapter,
178 I2C_FUNC_SMBUS_READ_WORD_DATA))
179 return -EIO;
180
181 ts = devm_kzalloc(dev: &client->dev, size: sizeof(*ts), GFP_KERNEL);
182 if (!ts)
183 return -ENOMEM;
184
185 input_dev = devm_input_allocate_device(&client->dev);
186 if (!input_dev)
187 return -ENOMEM;
188
189 ts->client = client;
190 ts->input = input_dev;
191
192 snprintf(buf: ts->phys, size: sizeof(ts->phys),
193 fmt: "%s/input0", dev_name(dev: &client->dev));
194
195 input_dev->name = CY8CTMG110_DRIVER_NAME " Touchscreen";
196 input_dev->phys = ts->phys;
197 input_dev->id.bustype = BUS_I2C;
198
199 input_set_capability(dev: input_dev, EV_KEY, BTN_TOUCH);
200 input_set_abs_params(dev: input_dev, ABS_X,
201 CY8CTMG110_X_MIN, CY8CTMG110_X_MAX, fuzz: 4, flat: 0);
202 input_set_abs_params(dev: input_dev, ABS_Y,
203 CY8CTMG110_Y_MIN, CY8CTMG110_Y_MAX, fuzz: 4, flat: 0);
204
205 /* Request and assert reset line */
206 ts->reset_gpio = devm_gpiod_get_optional(dev: &client->dev, NULL,
207 flags: GPIOD_OUT_HIGH);
208 if (IS_ERR(ptr: ts->reset_gpio)) {
209 err = PTR_ERR(ptr: ts->reset_gpio);
210 dev_err(&client->dev,
211 "Unable to request reset GPIO: %d\n", err);
212 return err;
213 }
214
215 cy8ctmg110_power(ts, poweron: true);
216 cy8ctmg110_set_sleepmode(ts, sleep: false);
217
218 err = devm_add_action_or_reset(&client->dev, cy8ctmg110_shut_off, ts);
219 if (err)
220 return err;
221
222 err = devm_request_threaded_irq(dev: &client->dev, irq: client->irq,
223 NULL, thread_fn: cy8ctmg110_irq_thread,
224 IRQF_ONESHOT, devname: "touch_reset_key", dev_id: ts);
225 if (err) {
226 dev_err(&client->dev,
227 "irq %d busy? error %d\n", client->irq, err);
228 return err;
229 }
230
231 err = input_register_device(input_dev);
232 if (err)
233 return err;
234
235 i2c_set_clientdata(client, data: ts);
236
237 return 0;
238}
239
240static int cy8ctmg110_suspend(struct device *dev)
241{
242 struct i2c_client *client = to_i2c_client(dev);
243 struct cy8ctmg110 *ts = i2c_get_clientdata(client);
244
245 if (!device_may_wakeup(dev: &client->dev)) {
246 cy8ctmg110_set_sleepmode(ts, sleep: true);
247 cy8ctmg110_power(ts, poweron: false);
248 }
249
250 return 0;
251}
252
253static int cy8ctmg110_resume(struct device *dev)
254{
255 struct i2c_client *client = to_i2c_client(dev);
256 struct cy8ctmg110 *ts = i2c_get_clientdata(client);
257
258 if (!device_may_wakeup(dev: &client->dev)) {
259 cy8ctmg110_power(ts, poweron: true);
260 cy8ctmg110_set_sleepmode(ts, sleep: false);
261 }
262
263 return 0;
264}
265
266static DEFINE_SIMPLE_DEV_PM_OPS(cy8ctmg110_pm,
267 cy8ctmg110_suspend, cy8ctmg110_resume);
268
269static const struct i2c_device_id cy8ctmg110_idtable[] = {
270 { CY8CTMG110_DRIVER_NAME, 1 },
271 { }
272};
273
274MODULE_DEVICE_TABLE(i2c, cy8ctmg110_idtable);
275
276static struct i2c_driver cy8ctmg110_driver = {
277 .driver = {
278 .name = CY8CTMG110_DRIVER_NAME,
279 .pm = pm_sleep_ptr(&cy8ctmg110_pm),
280 },
281 .id_table = cy8ctmg110_idtable,
282 .probe = cy8ctmg110_probe,
283};
284
285module_i2c_driver(cy8ctmg110_driver);
286
287MODULE_AUTHOR("Samuli Konttila <samuli.konttila@aavamobile.com>");
288MODULE_DESCRIPTION("cy8ctmg110 TouchScreen Driver");
289MODULE_LICENSE("GPL v2");
290

source code of linux/drivers/input/touchscreen/cy8ctmg110_ts.c