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