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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/slab.h>
27#include <linux/types.h>
28
29#define ST1232_TS_NAME "st1232-ts"
30
31#define MIN_X 0x00
32#define MIN_Y 0x00
33#define MAX_X 0x31f
34#define MAX_Y 0x1df
35#define MAX_AREA 0xff
36#define MAX_FINGERS 2
37
38struct st1232_ts_finger {
39 u16 x;
40 u16 y;
41 u8 t;
42 bool is_valid;
43};
44
45struct st1232_ts_data {
46 struct i2c_client *client;
47 struct input_dev *input_dev;
48 struct st1232_ts_finger finger[MAX_FINGERS];
49};
50
51static int st1232_ts_read_data(struct st1232_ts_data *ts)
52{
53 struct st1232_ts_finger *finger = ts->finger;
54 struct i2c_client *client = ts->client;
55 struct i2c_msg msg[2];
56 int error;
57 u8 start_reg;
58 u8 buf[10];
59
60
61 msg[0].addr = client->addr;
62 msg[0].flags = 0;
63 msg[0].len = 1;
64 msg[0].buf = &start_reg;
65 start_reg = 0x10;
66
67 msg[1].addr = ts->client->addr;
68 msg[1].flags = I2C_M_RD;
69 msg[1].len = sizeof(buf);
70 msg[1].buf = buf;
71
72 error = i2c_transfer(client->adapter, msg, 2);
73 if (error < 0)
74 return error;
75
76
77 finger[0].is_valid = buf[2] >> 7;
78 finger[1].is_valid = buf[5] >> 7;
79
80
81 if (finger[0].is_valid) {
82 finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
83 finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
84 finger[0].t = buf[8];
85 }
86
87 if (finger[1].is_valid) {
88 finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
89 finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
90 finger[1].t = buf[9];
91 }
92
93 return 0;
94}
95
96static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
97{
98 struct st1232_ts_data *ts = dev_id;
99 struct st1232_ts_finger *finger = ts->finger;
100 struct input_dev *input_dev = ts->input_dev;
101 int count = 0;
102 int i, ret;
103
104 ret = st1232_ts_read_data(ts);
105 if (ret < 0)
106 goto end;
107
108
109 for (i = 0; i < MAX_FINGERS; i++) {
110 if (!finger[i].is_valid)
111 continue;
112
113 input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
114 input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
115 input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
116 input_mt_sync(input_dev);
117 count++;
118 }
119
120
121 if (!count)
122 input_mt_sync(input_dev);
123
124
125 input_sync(input_dev);
126
127end:
128 return IRQ_HANDLED;
129}
130
131static int __devinit st1232_ts_probe(struct i2c_client *client,
132 const struct i2c_device_id *id)
133{
134 struct st1232_ts_data *ts;
135 struct input_dev *input_dev;
136 int error;
137
138 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
139 dev_err(&client->dev, "need I2C_FUNC_I2C\n");
140 return -EIO;
141 }
142
143 if (!client->irq) {
144 dev_err(&client->dev, "no IRQ?\n");
145 return -EINVAL;
146 }
147
148
149 ts = kzalloc(sizeof(struct st1232_ts_data), GFP_KERNEL);
150 input_dev = input_allocate_device();
151 if (!ts || !input_dev) {
152 error = -ENOMEM;
153 goto err_free_mem;
154 }
155
156 ts->client = client;
157 ts->input_dev = input_dev;
158
159 input_dev->name = "st1232-touchscreen";
160 input_dev->id.bustype = BUS_I2C;
161 input_dev->dev.parent = &client->dev;
162
163 __set_bit(EV_SYN, input_dev->evbit);
164 __set_bit(EV_KEY, input_dev->evbit);
165 __set_bit(EV_ABS, input_dev->evbit);
166
167 input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
168 input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
169 input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);
170
171 error = request_threaded_irq(client->irq, NULL, st1232_ts_irq_handler,
172 IRQF_ONESHOT, client->name, ts);
173 if (error) {
174 dev_err(&client->dev, "Failed to register interrupt\n");
175 goto err_free_mem;
176 }
177
178 error = input_register_device(ts->input_dev);
179 if (error) {
180 dev_err(&client->dev, "Unable to register %s input device\n",
181 input_dev->name);
182 goto err_free_irq;
183 }
184
185 i2c_set_clientdata(client, ts);
186 device_init_wakeup(&client->dev, 1);
187
188 return 0;
189
190err_free_irq:
191 free_irq(client->irq, ts);
192err_free_mem:
193 input_free_device(input_dev);
194 kfree(ts);
195 return error;
196}
197
198static int __devexit st1232_ts_remove(struct i2c_client *client)
199{
200 struct st1232_ts_data *ts = i2c_get_clientdata(client);
201
202 device_init_wakeup(&client->dev, 0);
203 free_irq(client->irq, ts);
204 input_unregister_device(ts->input_dev);
205 kfree(ts);
206
207 return 0;
208}
209
210#ifdef CONFIG_PM
211static int st1232_ts_suspend(struct device *dev)
212{
213 struct i2c_client *client = to_i2c_client(dev);
214
215 if (device_may_wakeup(&client->dev))
216 enable_irq_wake(client->irq);
217 else
218 disable_irq(client->irq);
219
220 return 0;
221}
222
223static int st1232_ts_resume(struct device *dev)
224{
225 struct i2c_client *client = to_i2c_client(dev);
226
227 if (device_may_wakeup(&client->dev))
228 disable_irq_wake(client->irq);
229 else
230 enable_irq(client->irq);
231
232 return 0;
233}
234
235static const struct dev_pm_ops st1232_ts_pm_ops = {
236 .suspend = st1232_ts_suspend,
237 .resume = st1232_ts_resume,
238};
239#endif
240
241static const struct i2c_device_id st1232_ts_id[] = {
242 { ST1232_TS_NAME, 0 },
243 { }
244};
245MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
246
247static struct i2c_driver st1232_ts_driver = {
248 .probe = st1232_ts_probe,
249 .remove = __devexit_p(st1232_ts_remove),
250 .id_table = st1232_ts_id,
251 .driver = {
252 .name = ST1232_TS_NAME,
253 .owner = THIS_MODULE,
254#ifdef CONFIG_PM
255 .pm = &st1232_ts_pm_ops,
256#endif
257 },
258};
259
260static int __init st1232_ts_init(void)
261{
262 return i2c_add_driver(&st1232_ts_driver);
263}
264module_init(st1232_ts_init);
265
266static void __exit st1232_ts_exit(void)
267{
268 i2c_del_driver(&st1232_ts_driver);
269}
270module_exit(st1232_ts_exit);
271
272MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
273MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
274MODULE_LICENSE("GPL");
275
