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