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/input/touchscreen.h>
9#include <linux/delay.h>
10#include <linux/workqueue.h>
11#include <linux/gpio/consumer.h>
12#include <linux/of_device.h>
13#include <asm/unaligned.h>
14
15#define ILI210X_TOUCHES 2
16#define ILI251X_TOUCHES 10
17#define DEFAULT_POLL_PERIOD 20
18
19
20#define REG_TOUCHDATA 0x10
21#define REG_PANEL_INFO 0x20
22#define REG_FIRMWARE_VERSION 0x40
23#define REG_CALIBRATE 0xcc
24
25struct firmware_version {
26 u8 id;
27 u8 major;
28 u8 minor;
29} __packed;
30
31enum ili2xxx_model {
32 MODEL_ILI210X,
33 MODEL_ILI251X,
34};
35
36struct ili210x {
37 struct i2c_client *client;
38 struct input_dev *input;
39 unsigned int poll_period;
40 struct delayed_work dwork;
41 struct gpio_desc *reset_gpio;
42 struct touchscreen_properties prop;
43 enum ili2xxx_model model;
44 unsigned int max_touches;
45};
46
47static int ili210x_read_reg(struct i2c_client *client, u8 reg, void *buf,
48 size_t len)
49{
50 struct ili210x *priv = i2c_get_clientdata(client);
51 struct i2c_msg msg[2] = {
52 {
53 .addr = client->addr,
54 .flags = 0,
55 .len = 1,
56 .buf = ®,
57 },
58 {
59 .addr = client->addr,
60 .flags = I2C_M_RD,
61 .len = len,
62 .buf = buf,
63 }
64 };
65
66 if (priv->model == MODEL_ILI251X) {
67 if (i2c_transfer(client->adapter, msg, 1) != 1) {
68 dev_err(&client->dev, "i2c transfer failed\n");
69 return -EIO;
70 }
71
72 usleep_range(5000, 5500);
73
74 if (i2c_transfer(client->adapter, msg + 1, 1) != 1) {
75 dev_err(&client->dev, "i2c transfer failed\n");
76 return -EIO;
77 }
78 } else {
79 if (i2c_transfer(client->adapter, msg, 2) != 2) {
80 dev_err(&client->dev, "i2c transfer failed\n");
81 return -EIO;
82 }
83 }
84
85 return 0;
86}
87
88static int ili210x_read(struct i2c_client *client, void *buf, size_t len)
89{
90 struct i2c_msg msg = {
91 .addr = client->addr,
92 .flags = I2C_M_RD,
93 .len = len,
94 .buf = buf,
95 };
96
97 if (i2c_transfer(client->adapter, &msg, 1) != 1) {
98 dev_err(&client->dev, "i2c transfer failed\n");
99 return -EIO;
100 }
101
102 return 0;
103}
104
105static bool ili210x_touchdata_to_coords(struct ili210x *priv, u8 *touchdata,
106 unsigned int finger,
107 unsigned int *x, unsigned int *y)
108{
109 if (finger >= ILI210X_TOUCHES)
110 return false;
111
112 if (touchdata[0] & BIT(finger))
113 return false;
114
115 *x = get_unaligned_be16(touchdata + 1 + (finger * 4) + 0);
116 *y = get_unaligned_be16(touchdata + 1 + (finger * 4) + 2);
117
118 return true;
119}
120
121static bool ili251x_touchdata_to_coords(struct ili210x *priv, u8 *touchdata,
122 unsigned int finger,
123 unsigned int *x, unsigned int *y)
124{
125 if (finger >= ILI251X_TOUCHES)
126 return false;
127
128 *x = get_unaligned_be16(touchdata + 1 + (finger * 5) + 0);
129 if (!(*x & BIT(15)))
130 return false;
131
132 *x &= 0x3fff;
133 *y = get_unaligned_be16(touchdata + 1 + (finger * 5) + 2);
134
135 return true;
136}
137
138static bool ili210x_report_events(struct ili210x *priv, u8 *touchdata)
139{
140 struct input_dev *input = priv->input;
141 int i;
142 bool contact = false, touch = false;
143 unsigned int x = 0, y = 0;
144
145 for (i = 0; i < priv->max_touches; i++) {
146 if (priv->model == MODEL_ILI210X) {
147 touch = ili210x_touchdata_to_coords(priv, touchdata,
148 i, &x, &y);
149 } else if (priv->model == MODEL_ILI251X) {
150 touch = ili251x_touchdata_to_coords(priv, touchdata,
151 i, &x, &y);
152 if (touch)
153 contact = true;
154 }
155
156 input_mt_slot(input, i);
157 input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
158 if (!touch)
159 continue;
160 touchscreen_report_pos(input, &priv->prop, x, y,
161 true);
162 }
163
164 input_mt_report_pointer_emulation(input, false);
165 input_sync(input);
166
167 if (priv->model == MODEL_ILI210X)
168 contact = touchdata[0] & 0xf3;
169
170 return contact;
171}
172
173static void ili210x_work(struct work_struct *work)
174{
175 struct ili210x *priv = container_of(work, struct ili210x,
176 dwork.work);
177 struct i2c_client *client = priv->client;
178 u8 touchdata[64] = { 0 };
179 bool touch;
180 int error = -EINVAL;
181
182 if (priv->model == MODEL_ILI210X) {
183 error = ili210x_read_reg(client, REG_TOUCHDATA,
184 touchdata, sizeof(touchdata));
185 } else if (priv->model == MODEL_ILI251X) {
186 error = ili210x_read_reg(client, REG_TOUCHDATA,
187 touchdata, 31);
188 if (!error && touchdata[0] == 2)
189 error = ili210x_read(client, &touchdata[31], 20);
190 }
191
192 if (error) {
193 dev_err(&client->dev,
194 "Unable to get touchdata, err = %d\n", error);
195 return;
196 }
197
198 touch = ili210x_report_events(priv, touchdata);
199
200 if (touch)
201 schedule_delayed_work(&priv->dwork,
202 msecs_to_jiffies(priv->poll_period));
203}
204
205static irqreturn_t ili210x_irq(int irq, void *irq_data)
206{
207 struct ili210x *priv = irq_data;
208
209 schedule_delayed_work(&priv->dwork, 0);
210
211 return IRQ_HANDLED;
212}
213
214static ssize_t ili210x_calibrate(struct device *dev,
215 struct device_attribute *attr,
216 const char *buf, size_t count)
217{
218 struct i2c_client *client = to_i2c_client(dev);
219 struct ili210x *priv = i2c_get_clientdata(client);
220 unsigned long calibrate;
221 int rc;
222 u8 cmd = REG_CALIBRATE;
223
224 if (kstrtoul(buf, 10, &calibrate))
225 return -EINVAL;
226
227 if (calibrate > 1)
228 return -EINVAL;
229
230 if (calibrate) {
231 rc = i2c_master_send(priv->client, &cmd, sizeof(cmd));
232 if (rc != sizeof(cmd))
233 return -EIO;
234 }
235
236 return count;
237}
238static DEVICE_ATTR(calibrate, S_IWUSR, NULL, ili210x_calibrate);
239
240static struct attribute *ili210x_attributes[] = {
241 &dev_attr_calibrate.attr,
242 NULL,
243};
244
245static const struct attribute_group ili210x_attr_group = {
246 .attrs = ili210x_attributes,
247};
248
249static void ili210x_power_down(void *data)
250{
251 struct gpio_desc *reset_gpio = data;
252
253 gpiod_set_value_cansleep(reset_gpio, 1);
254}
255
256static void ili210x_cancel_work(void *data)
257{
258 struct ili210x *priv = data;
259
260 cancel_delayed_work_sync(&priv->dwork);
261}
262
263static int ili210x_i2c_probe(struct i2c_client *client,
264 const struct i2c_device_id *id)
265{
266 struct device *dev = &client->dev;
267 struct ili210x *priv;
268 struct gpio_desc *reset_gpio;
269 struct input_dev *input;
270 struct firmware_version firmware;
271 enum ili2xxx_model model;
272 int error;
273
274 model = (enum ili2xxx_model)id->driver_data;
275
276 dev_dbg(dev, "Probing for ILI210X I2C Touschreen driver");
277
278 if (client->irq <= 0) {
279 dev_err(dev, "No IRQ!\n");
280 return -EINVAL;
281 }
282
283 reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
284 if (IS_ERR(reset_gpio))
285 return PTR_ERR(reset_gpio);
286
287 if (reset_gpio) {
288 error = devm_add_action_or_reset(dev, ili210x_power_down,
289 reset_gpio);
290 if (error)
291 return error;
292
293 usleep_range(50, 100);
294 gpiod_set_value_cansleep(reset_gpio, 0);
295 msleep(100);
296 }
297
298 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
299 if (!priv)
300 return -ENOMEM;
301
302 input = devm_input_allocate_device(dev);
303 if (!input)
304 return -ENOMEM;
305
306 priv->client = client;
307 priv->input = input;
308 priv->poll_period = DEFAULT_POLL_PERIOD;
309 INIT_DELAYED_WORK(&priv->dwork, ili210x_work);
310 priv->reset_gpio = reset_gpio;
311 priv->model = model;
312 if (model == MODEL_ILI210X)
313 priv->max_touches = ILI210X_TOUCHES;
314 if (model == MODEL_ILI251X)
315 priv->max_touches = ILI251X_TOUCHES;
316
317 i2c_set_clientdata(client, priv);
318
319
320 error = ili210x_read_reg(client, REG_FIRMWARE_VERSION,
321 &firmware, sizeof(firmware));
322 if (error) {
323 dev_err(dev, "Failed to get firmware version, err: %d\n",
324 error);
325 return error;
326 }
327
328
329 input->name = "ILI210x Touchscreen";
330 input->id.bustype = BUS_I2C;
331 input->dev.parent = dev;
332
333
334 input_set_abs_params(input, ABS_MT_POSITION_X, 0, 0xffff, 0, 0);
335 input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 0xffff, 0, 0);
336 touchscreen_parse_properties(input, true, &priv->prop);
337 input_mt_init_slots(input, priv->max_touches, INPUT_MT_DIRECT);
338
339 error = devm_add_action(dev, ili210x_cancel_work, priv);
340 if (error)
341 return error;
342
343 error = devm_request_irq(dev, client->irq, ili210x_irq, 0,
344 client->name, priv);
345 if (error) {
346 dev_err(dev, "Unable to request touchscreen IRQ, err: %d\n",
347 error);
348 return error;
349 }
350
351 error = devm_device_add_group(dev, &ili210x_attr_group);
352 if (error) {
353 dev_err(dev, "Unable to create sysfs attributes, err: %d\n",
354 error);
355 return error;
356 }
357
358 error = input_register_device(priv->input);
359 if (error) {
360 dev_err(dev, "Cannot register input device, err: %d\n", error);
361 return error;
362 }
363
364 device_init_wakeup(dev, 1);
365
366 dev_dbg(dev,
367 "ILI210x initialized (IRQ: %d), firmware version %d.%d.%d",
368 client->irq, firmware.id, firmware.major, firmware.minor);
369
370 return 0;
371}
372
373static int __maybe_unused ili210x_i2c_suspend(struct device *dev)
374{
375 struct i2c_client *client = to_i2c_client(dev);
376
377 if (device_may_wakeup(&client->dev))
378 enable_irq_wake(client->irq);
379
380 return 0;
381}
382
383static int __maybe_unused ili210x_i2c_resume(struct device *dev)
384{
385 struct i2c_client *client = to_i2c_client(dev);
386
387 if (device_may_wakeup(&client->dev))
388 disable_irq_wake(client->irq);
389
390 return 0;
391}
392
393static SIMPLE_DEV_PM_OPS(ili210x_i2c_pm,
394 ili210x_i2c_suspend, ili210x_i2c_resume);
395
396static const struct i2c_device_id ili210x_i2c_id[] = {
397 { "ili210x", MODEL_ILI210X },
398 { "ili251x", MODEL_ILI251X },
399 { }
400};
401MODULE_DEVICE_TABLE(i2c, ili210x_i2c_id);
402
403static const struct of_device_id ili210x_dt_ids[] = {
404 { .compatible = "ilitek,ili210x", .data = (void *)MODEL_ILI210X },
405 { .compatible = "ilitek,ili251x", .data = (void *)MODEL_ILI251X },
406 { },
407};
408MODULE_DEVICE_TABLE(of, ili210x_dt_ids);
409
410static struct i2c_driver ili210x_ts_driver = {
411 .driver = {
412 .name = "ili210x_i2c",
413 .pm = &ili210x_i2c_pm,
414 .of_match_table = ili210x_dt_ids,
415 },
416 .id_table = ili210x_i2c_id,
417 .probe = ili210x_i2c_probe,
418};
419
420module_i2c_driver(ili210x_ts_driver);
421
422MODULE_AUTHOR("Olivier Sobrie <olivier@sobrie.be>");
423MODULE_DESCRIPTION("ILI210X I2C Touchscreen Driver");
424MODULE_LICENSE("GPL");
425
