1
2#include <linux/module.h>
3#include <linux/i2c.h>
4#include <linux/interrupt.h>
5#include <linux/slab.h>
6#include <linux/input.h>
7#include <linux/input/mt.h>
8#include <linux/delay.h>
9#include <linux/workqueue.h>
10#include <linux/input/ili210x.h>
11
12#define MAX_TOUCHES 2
13#define DEFAULT_POLL_PERIOD 20
14
15
16#define REG_TOUCHDATA 0x10
17#define REG_PANEL_INFO 0x20
18#define REG_FIRMWARE_VERSION 0x40
19#define REG_CALIBRATE 0xcc
20
21struct finger {
22 u8 x_low;
23 u8 x_high;
24 u8 y_low;
25 u8 y_high;
26} __packed;
27
28struct touchdata {
29 u8 status;
30 struct finger finger[MAX_TOUCHES];
31} __packed;
32
33struct panel_info {
34 struct finger finger_max;
35 u8 xchannel_num;
36 u8 ychannel_num;
37} __packed;
38
39struct firmware_version {
40 u8 id;
41 u8 major;
42 u8 minor;
43} __packed;
44
45struct ili210x {
46 struct i2c_client *client;
47 struct input_dev *input;
48 bool (*get_pendown_state)(void);
49 unsigned int poll_period;
50 struct delayed_work dwork;
51};
52
53static int ili210x_read_reg(struct i2c_client *client, u8 reg, void *buf,
54 size_t len)
55{
56 struct i2c_msg msg[2] = {
57 {
58 .addr = client->addr,
59 .flags = 0,
60 .len = 1,
61 .buf = ®,
62 },
63 {
64 .addr = client->addr,
65 .flags = I2C_M_RD,
66 .len = len,
67 .buf = buf,
68 }
69 };
70
71 if (i2c_transfer(client->adapter, msg, 2) != 2) {
72 dev_err(&client->dev, "i2c transfer failed\n");
73 return -EIO;
74 }
75
76 return 0;
77}
78
79static void ili210x_report_events(struct input_dev *input,
80 const struct touchdata *touchdata)
81{
82 int i;
83 bool touch;
84 unsigned int x, y;
85 const struct finger *finger;
86
87 for (i = 0; i < MAX_TOUCHES; i++) {
88 input_mt_slot(input, i);
89
90 finger = &touchdata->finger[i];
91
92 touch = touchdata->status & (1 << i);
93 input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
94 if (touch) {
95 x = finger->x_low | (finger->x_high << 8);
96 y = finger->y_low | (finger->y_high << 8);
97
98 input_report_abs(input, ABS_MT_POSITION_X, x);
99 input_report_abs(input, ABS_MT_POSITION_Y, y);
100 }
101 }
102
103 input_mt_report_pointer_emulation(input, false);
104 input_sync(input);
105}
106
107static bool get_pendown_state(const struct ili210x *priv)
108{
109 bool state = false;
110
111 if (priv->get_pendown_state)
112 state = priv->get_pendown_state();
113
114 return state;
115}
116
117static void ili210x_work(struct work_struct *work)
118{
119 struct ili210x *priv = container_of(work, struct ili210x,
120 dwork.work);
121 struct i2c_client *client = priv->client;
122 struct touchdata touchdata;
123 int error;
124
125 error = ili210x_read_reg(client, REG_TOUCHDATA,
126 &touchdata, sizeof(touchdata));
127 if (error) {
128 dev_err(&client->dev,
129 "Unable to get touchdata, err = %d\n", error);
130 return;
131 }
132
133 ili210x_report_events(priv->input, &touchdata);
134
135 if ((touchdata.status & 0xf3) || get_pendown_state(priv))
136 schedule_delayed_work(&priv->dwork,
137 msecs_to_jiffies(priv->poll_period));
138}
139
140static irqreturn_t ili210x_irq(int irq, void *irq_data)
141{
142 struct ili210x *priv = irq_data;
143
144 schedule_delayed_work(&priv->dwork, 0);
145
146 return IRQ_HANDLED;
147}
148
149static ssize_t ili210x_calibrate(struct device *dev,
150 struct device_attribute *attr,
151 const char *buf, size_t count)
152{
153 struct i2c_client *client = to_i2c_client(dev);
154 struct ili210x *priv = i2c_get_clientdata(client);
155 unsigned long calibrate;
156 int rc;
157 u8 cmd = REG_CALIBRATE;
158
159 if (kstrtoul(buf, 10, &calibrate))
160 return -EINVAL;
161
162 if (calibrate > 1)
163 return -EINVAL;
164
165 if (calibrate) {
166 rc = i2c_master_send(priv->client, &cmd, sizeof(cmd));
167 if (rc != sizeof(cmd))
168 return -EIO;
169 }
170
171 return count;
172}
173static DEVICE_ATTR(calibrate, S_IWUSR, NULL, ili210x_calibrate);
174
175static struct attribute *ili210x_attributes[] = {
176 &dev_attr_calibrate.attr,
177 NULL,
178};
179
180static const struct attribute_group ili210x_attr_group = {
181 .attrs = ili210x_attributes,
182};
183
184static int ili210x_i2c_probe(struct i2c_client *client,
185 const struct i2c_device_id *id)
186{
187 struct device *dev = &client->dev;
188 const struct ili210x_platform_data *pdata = dev_get_platdata(dev);
189 struct ili210x *priv;
190 struct input_dev *input;
191 struct panel_info panel;
192 struct firmware_version firmware;
193 int xmax, ymax;
194 int error;
195
196 dev_dbg(dev, "Probing for ILI210X I2C Touschreen driver");
197
198 if (!pdata) {
199 dev_err(dev, "No platform data!\n");
200 return -EINVAL;
201 }
202
203 if (client->irq <= 0) {
204 dev_err(dev, "No IRQ!\n");
205 return -EINVAL;
206 }
207
208
209 error = ili210x_read_reg(client, REG_FIRMWARE_VERSION,
210 &firmware, sizeof(firmware));
211 if (error) {
212 dev_err(dev, "Failed to get firmware version, err: %d\n",
213 error);
214 return error;
215 }
216
217
218 error = ili210x_read_reg(client, REG_PANEL_INFO, &panel, sizeof(panel));
219 if (error) {
220 dev_err(dev, "Failed to get panel information, err: %d\n",
221 error);
222 return error;
223 }
224
225 xmax = panel.finger_max.x_low | (panel.finger_max.x_high << 8);
226 ymax = panel.finger_max.y_low | (panel.finger_max.y_high << 8);
227
228 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
229 input = input_allocate_device();
230 if (!priv || !input) {
231 error = -ENOMEM;
232 goto err_free_mem;
233 }
234
235 priv->client = client;
236 priv->input = input;
237 priv->get_pendown_state = pdata->get_pendown_state;
238 priv->poll_period = pdata->poll_period ? : DEFAULT_POLL_PERIOD;
239 INIT_DELAYED_WORK(&priv->dwork, ili210x_work);
240
241
242 input->name = "ILI210x Touchscreen";
243 input->id.bustype = BUS_I2C;
244 input->dev.parent = dev;
245
246 __set_bit(EV_SYN, input->evbit);
247 __set_bit(EV_KEY, input->evbit);
248 __set_bit(EV_ABS, input->evbit);
249 __set_bit(BTN_TOUCH, input->keybit);
250
251
252 input_set_abs_params(input, ABS_X, 0, xmax, 0, 0);
253 input_set_abs_params(input, ABS_Y, 0, ymax, 0, 0);
254
255
256 input_mt_init_slots(input, MAX_TOUCHES, 0);
257 input_set_abs_params(input, ABS_MT_POSITION_X, 0, xmax, 0, 0);
258 input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ymax, 0, 0);
259
260 i2c_set_clientdata(client, priv);
261
262 error = request_irq(client->irq, ili210x_irq, pdata->irq_flags,
263 client->name, priv);
264 if (error) {
265 dev_err(dev, "Unable to request touchscreen IRQ, err: %d\n",
266 error);
267 goto err_free_mem;
268 }
269
270 error = sysfs_create_group(&dev->kobj, &ili210x_attr_group);
271 if (error) {
272 dev_err(dev, "Unable to create sysfs attributes, err: %d\n",
273 error);
274 goto err_free_irq;
275 }
276
277 error = input_register_device(priv->input);
278 if (error) {
279 dev_err(dev, "Cannot register input device, err: %d\n", error);
280 goto err_remove_sysfs;
281 }
282
283 device_init_wakeup(dev, 1);
284
285 dev_dbg(dev,
286 "ILI210x initialized (IRQ: %d), firmware version %d.%d.%d",
287 client->irq, firmware.id, firmware.major, firmware.minor);
288
289 return 0;
290
291err_remove_sysfs:
292 sysfs_remove_group(&dev->kobj, &ili210x_attr_group);
293err_free_irq:
294 free_irq(client->irq, priv);
295err_free_mem:
296 input_free_device(input);
297 kfree(priv);
298 return error;
299}
300
301static int ili210x_i2c_remove(struct i2c_client *client)
302{
303 struct ili210x *priv = i2c_get_clientdata(client);
304
305 sysfs_remove_group(&client->dev.kobj, &ili210x_attr_group);
306 free_irq(priv->client->irq, priv);
307 cancel_delayed_work_sync(&priv->dwork);
308 input_unregister_device(priv->input);
309 kfree(priv);
310
311 return 0;
312}
313
314static int __maybe_unused ili210x_i2c_suspend(struct device *dev)
315{
316 struct i2c_client *client = to_i2c_client(dev);
317
318 if (device_may_wakeup(&client->dev))
319 enable_irq_wake(client->irq);
320
321 return 0;
322}
323
324static int __maybe_unused ili210x_i2c_resume(struct device *dev)
325{
326 struct i2c_client *client = to_i2c_client(dev);
327
328 if (device_may_wakeup(&client->dev))
329 disable_irq_wake(client->irq);
330
331 return 0;
332}
333
334static SIMPLE_DEV_PM_OPS(ili210x_i2c_pm,
335 ili210x_i2c_suspend, ili210x_i2c_resume);
336
337static const struct i2c_device_id ili210x_i2c_id[] = {
338 { "ili210x", 0 },
339 { }
340};
341MODULE_DEVICE_TABLE(i2c, ili210x_i2c_id);
342
343static struct i2c_driver ili210x_ts_driver = {
344 .driver = {
345 .name = "ili210x_i2c",
346 .pm = &ili210x_i2c_pm,
347 },
348 .id_table = ili210x_i2c_id,
349 .probe = ili210x_i2c_probe,
350 .remove = ili210x_i2c_remove,
351};
352
353module_i2c_driver(ili210x_ts_driver);
354
355MODULE_AUTHOR("Olivier Sobrie <olivier@sobrie.be>");
356MODULE_DESCRIPTION("ILI210X I2C Touchscreen Driver");
357MODULE_LICENSE("GPL");
358
