1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21#include <linux/delay.h>
22#include <linux/gpio.h>
23#include <linux/i2c.h>
24#include <linux/input.h>
25#include <linux/interrupt.h>
26#include <linux/module.h>
27#include <linux/of.h>
28#include <linux/of_gpio.h>
29#include <linux/pm_qos.h>
30#include <linux/slab.h>
31#include <linux/types.h>
32
33#define ST1232_TS_NAME "st1232-ts"
34
35#define MIN_X 0x00
36#define MIN_Y 0x00
37#define MAX_X 0x31f
38#define MAX_Y 0x1df
39#define MAX_AREA 0xff
40#define MAX_FINGERS 2
41
42struct st1232_ts_finger {
43 u16 x;
44 u16 y;
45 u8 t;
46 bool is_valid;
47};
48
49struct st1232_ts_data {
50 struct i2c_client *client;
51 struct input_dev *input_dev;
52 struct st1232_ts_finger finger[MAX_FINGERS];
53 struct dev_pm_qos_request low_latency_req;
54 int reset_gpio;
55};
56
57static int st1232_ts_read_data(struct st1232_ts_data *ts)
58{
59 struct st1232_ts_finger *finger = ts->finger;
60 struct i2c_client *client = ts->client;
61 struct i2c_msg msg[2];
62 int error;
63 u8 start_reg;
64 u8 buf[10];
65
66
67 msg[0].addr = client->addr;
68 msg[0].flags = 0;
69 msg[0].len = 1;
70 msg[0].buf = &start_reg;
71 start_reg = 0x10;
72
73 msg[1].addr = ts->client->addr;
74 msg[1].flags = I2C_M_RD;
75 msg[1].len = sizeof(buf);
76 msg[1].buf = buf;
77
78 error = i2c_transfer(client->adapter, msg, 2);
79 if (error < 0)
80 return error;
81
82
83 finger[0].is_valid = buf[2] >> 7;
84 finger[1].is_valid = buf[5] >> 7;
85
86
87 if (finger[0].is_valid) {
88 finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
89 finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
90 finger[0].t = buf[8];
91 }
92
93 if (finger[1].is_valid) {
94 finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
95 finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
96 finger[1].t = buf[9];
97 }
98
99 return 0;
100}
101
102static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
103{
104 struct st1232_ts_data *ts = dev_id;
105 struct st1232_ts_finger *finger = ts->finger;
106 struct input_dev *input_dev = ts->input_dev;
107 int count = 0;
108 int i, ret;
109
110 ret = st1232_ts_read_data(ts);
111 if (ret < 0)
112 goto end;
113
114
115 for (i = 0; i < MAX_FINGERS; i++) {
116 if (!finger[i].is_valid)
117 continue;
118
119 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
120 input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
121 input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
122 input_mt_sync(input_dev);
123 count++;
124 }
125
126
127 if (!count) {
128 input_mt_sync(input_dev);
129 if (ts->low_latency_req.dev) {
130 dev_pm_qos_remove_request(&ts->low_latency_req);
131 ts->low_latency_req.dev = NULL;
132 }
133 } else if (!ts->low_latency_req.dev) {
134
135 dev_pm_qos_add_ancestor_request(&ts->client->dev,
136 &ts->low_latency_req,
137 DEV_PM_QOS_RESUME_LATENCY, 100);
138 }
139
140
141 input_sync(input_dev);
142
143end:
144 return IRQ_HANDLED;
145}
146
147static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
148{
149 if (gpio_is_valid(ts->reset_gpio))
150 gpio_direction_output(ts->reset_gpio, poweron);
151}
152
153static int st1232_ts_probe(struct i2c_client *client,
154 const struct i2c_device_id *id)
155{
156 struct st1232_ts_data *ts;
157 struct input_dev *input_dev;
158 int error;
159
160 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
161 dev_err(&client->dev, "need I2C_FUNC_I2C\n");
162 return -EIO;
163 }
164
165 if (!client->irq) {
166 dev_err(&client->dev, "no IRQ?\n");
167 return -EINVAL;
168 }
169
170 ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
171 if (!ts)
172 return -ENOMEM;
173
174 input_dev = devm_input_allocate_device(&client->dev);
175 if (!input_dev)
176 return -ENOMEM;
177
178 ts->client = client;
179 ts->input_dev = input_dev;
180
181 ts->reset_gpio = of_get_gpio(client->dev.of_node, 0);
182 if (gpio_is_valid(ts->reset_gpio)) {
183 error = devm_gpio_request(&client->dev, ts->reset_gpio, NULL);
184 if (error) {
185 dev_err(&client->dev,
186 "Unable to request GPIO pin %d.\n",
187 ts->reset_gpio);
188 return error;
189 }
190 }
191
192 st1232_ts_power(ts, true);
193
194 input_dev->name = "st1232-touchscreen";
195 input_dev->id.bustype = BUS_I2C;
196 input_dev->dev.parent = &client->dev;
197
198 __set_bit(EV_SYN, input_dev->evbit);
199 __set_bit(EV_KEY, input_dev->evbit);
200 __set_bit(EV_ABS, input_dev->evbit);
201
202 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
203 input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
204 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);
205
206 error = devm_request_threaded_irq(&client->dev, client->irq,
207 NULL, st1232_ts_irq_handler,
208 IRQF_ONESHOT,
209 client->name, ts);
210 if (error) {
211 dev_err(&client->dev, "Failed to register interrupt\n");
212 return error;
213 }
214
215 error = input_register_device(ts->input_dev);
216 if (error) {
217 dev_err(&client->dev, "Unable to register %s input device\n",
218 input_dev->name);
219 return error;
220 }
221
222 i2c_set_clientdata(client, ts);
223 device_init_wakeup(&client->dev, 1);
224
225 return 0;
226}
227
228static int st1232_ts_remove(struct i2c_client *client)
229{
230 struct st1232_ts_data *ts = i2c_get_clientdata(client);
231
232 st1232_ts_power(ts, false);
233
234 return 0;
235}
236
237static int __maybe_unused st1232_ts_suspend(struct device *dev)
238{
239 struct i2c_client *client = to_i2c_client(dev);
240 struct st1232_ts_data *ts = i2c_get_clientdata(client);
241
242 if (device_may_wakeup(&client->dev)) {
243 enable_irq_wake(client->irq);
244 } else {
245 disable_irq(client->irq);
246 st1232_ts_power(ts, false);
247 }
248
249 return 0;
250}
251
252static int __maybe_unused st1232_ts_resume(struct device *dev)
253{
254 struct i2c_client *client = to_i2c_client(dev);
255 struct st1232_ts_data *ts = i2c_get_clientdata(client);
256
257 if (device_may_wakeup(&client->dev)) {
258 disable_irq_wake(client->irq);
259 } else {
260 st1232_ts_power(ts, true);
261 enable_irq(client->irq);
262 }
263
264 return 0;
265}
266
267static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
268 st1232_ts_suspend, st1232_ts_resume);
269
270static const struct i2c_device_id st1232_ts_id[] = {
271 { ST1232_TS_NAME, 0 },
272 { }
273};
274MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
275
276static const struct of_device_id st1232_ts_dt_ids[] = {
277 { .compatible = "sitronix,st1232", },
278 { }
279};
280MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
281
282static struct i2c_driver st1232_ts_driver = {
283 .probe = st1232_ts_probe,
284 .remove = st1232_ts_remove,
285 .id_table = st1232_ts_id,
286 .driver = {
287 .name = ST1232_TS_NAME,
288 .of_match_table = st1232_ts_dt_ids,
289 .pm = &st1232_ts_pm_ops,
290 },
291};
292
293module_i2c_driver(st1232_ts_driver);
294
295MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
296MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
297MODULE_LICENSE("GPL");
298
