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15#include <linux/gpio/consumer.h>
16#include <linux/interrupt.h>
17#include <linux/i2c.h>
18#include <linux/input.h>
19#include <linux/input/mt.h>
20#include <linux/module.h>
21#include <linux/of.h>
22
23#define ICN8318_REG_POWER 4
24#define ICN8318_REG_TOUCHDATA 16
25
26#define ICN8318_POWER_ACTIVE 0
27#define ICN8318_POWER_MONITOR 1
28#define ICN8318_POWER_HIBERNATE 2
29
30#define ICN8318_MAX_TOUCHES 5
31
32struct icn8318_touch {
33 __u8 slot;
34 __be16 x;
35 __be16 y;
36 __u8 pressure;
37 __u8 event;
38
39#define ICN8318_EVENT_NO_DATA 1
40#define ICN8318_EVENT_UPDATE1 2
41#define ICN8318_EVENT_UPDATE2 3
42#define ICN8318_EVENT_END 4
43} __packed;
44
45struct icn8318_touch_data {
46 __u8 softbutton;
47 __u8 touch_count;
48 struct icn8318_touch touches[ICN8318_MAX_TOUCHES];
49} __packed;
50
51struct icn8318_data {
52 struct i2c_client *client;
53 struct input_dev *input;
54 struct gpio_desc *wake_gpio;
55 u32 max_x;
56 u32 max_y;
57 bool invert_x;
58 bool invert_y;
59 bool swap_x_y;
60};
61
62static int icn8318_read_touch_data(struct i2c_client *client,
63 struct icn8318_touch_data *touch_data)
64{
65 u8 reg = ICN8318_REG_TOUCHDATA;
66 struct i2c_msg msg[2] = {
67 {
68 .addr = client->addr,
69 .len = 1,
70 .buf = ®
71 },
72 {
73 .addr = client->addr,
74 .flags = I2C_M_RD,
75 .len = sizeof(struct icn8318_touch_data),
76 .buf = (u8 *)touch_data
77 }
78 };
79
80 return i2c_transfer(client->adapter, msg, 2);
81}
82
83static inline bool icn8318_touch_active(u8 event)
84{
85 return (event == ICN8318_EVENT_UPDATE1) ||
86 (event == ICN8318_EVENT_UPDATE2);
87}
88
89static irqreturn_t icn8318_irq(int irq, void *dev_id)
90{
91 struct icn8318_data *data = dev_id;
92 struct device *dev = &data->client->dev;
93 struct icn8318_touch_data touch_data;
94 int i, ret, x, y;
95
96 ret = icn8318_read_touch_data(data->client, &touch_data);
97 if (ret < 0) {
98 dev_err(dev, "Error reading touch data: %d\n", ret);
99 return IRQ_HANDLED;
100 }
101
102 if (touch_data.softbutton) {
103
104
105
106
107
108
109 return IRQ_HANDLED;
110 }
111
112 if (touch_data.touch_count > ICN8318_MAX_TOUCHES) {
113 dev_warn(dev, "Too much touches %d > %d\n",
114 touch_data.touch_count, ICN8318_MAX_TOUCHES);
115 touch_data.touch_count = ICN8318_MAX_TOUCHES;
116 }
117
118 for (i = 0; i < touch_data.touch_count; i++) {
119 struct icn8318_touch *touch = &touch_data.touches[i];
120 bool act = icn8318_touch_active(touch->event);
121
122 input_mt_slot(data->input, touch->slot);
123 input_mt_report_slot_state(data->input, MT_TOOL_FINGER, act);
124 if (!act)
125 continue;
126
127 x = be16_to_cpu(touch->x);
128 y = be16_to_cpu(touch->y);
129
130 if (data->invert_x)
131 x = data->max_x - x;
132
133 if (data->invert_y)
134 y = data->max_y - y;
135
136 if (!data->swap_x_y) {
137 input_event(data->input, EV_ABS, ABS_MT_POSITION_X, x);
138 input_event(data->input, EV_ABS, ABS_MT_POSITION_Y, y);
139 } else {
140 input_event(data->input, EV_ABS, ABS_MT_POSITION_X, y);
141 input_event(data->input, EV_ABS, ABS_MT_POSITION_Y, x);
142 }
143 }
144
145 input_mt_sync_frame(data->input);
146 input_sync(data->input);
147
148 return IRQ_HANDLED;
149}
150
151static int icn8318_start(struct input_dev *dev)
152{
153 struct icn8318_data *data = input_get_drvdata(dev);
154
155 enable_irq(data->client->irq);
156 gpiod_set_value_cansleep(data->wake_gpio, 1);
157
158 return 0;
159}
160
161static void icn8318_stop(struct input_dev *dev)
162{
163 struct icn8318_data *data = input_get_drvdata(dev);
164
165 disable_irq(data->client->irq);
166 i2c_smbus_write_byte_data(data->client, ICN8318_REG_POWER,
167 ICN8318_POWER_HIBERNATE);
168 gpiod_set_value_cansleep(data->wake_gpio, 0);
169}
170
171#ifdef CONFIG_PM_SLEEP
172static int icn8318_suspend(struct device *dev)
173{
174 struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
175
176 mutex_lock(&data->input->mutex);
177 if (data->input->users)
178 icn8318_stop(data->input);
179 mutex_unlock(&data->input->mutex);
180
181 return 0;
182}
183
184static int icn8318_resume(struct device *dev)
185{
186 struct icn8318_data *data = i2c_get_clientdata(to_i2c_client(dev));
187
188 mutex_lock(&data->input->mutex);
189 if (data->input->users)
190 icn8318_start(data->input);
191 mutex_unlock(&data->input->mutex);
192
193 return 0;
194}
195#endif
196
197static SIMPLE_DEV_PM_OPS(icn8318_pm_ops, icn8318_suspend, icn8318_resume);
198
199static int icn8318_probe(struct i2c_client *client,
200 const struct i2c_device_id *id)
201{
202 struct device *dev = &client->dev;
203 struct device_node *np = dev->of_node;
204 struct icn8318_data *data;
205 struct input_dev *input;
206 u32 fuzz_x = 0, fuzz_y = 0;
207 int error;
208
209 if (!client->irq) {
210 dev_err(dev, "Error no irq specified\n");
211 return -EINVAL;
212 }
213
214 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
215 if (!data)
216 return -ENOMEM;
217
218 data->wake_gpio = devm_gpiod_get(dev, "wake", GPIOD_OUT_LOW);
219 if (IS_ERR(data->wake_gpio)) {
220 error = PTR_ERR(data->wake_gpio);
221 if (error != -EPROBE_DEFER)
222 dev_err(dev, "Error getting wake gpio: %d\n", error);
223 return error;
224 }
225
226 if (of_property_read_u32(np, "touchscreen-size-x", &data->max_x) ||
227 of_property_read_u32(np, "touchscreen-size-y", &data->max_y)) {
228 dev_err(dev, "Error touchscreen-size-x and/or -y missing\n");
229 return -EINVAL;
230 }
231
232
233 of_property_read_u32(np, "touchscreen-fuzz-x", &fuzz_x);
234 of_property_read_u32(np, "touchscreen-fuzz-y", &fuzz_y);
235 data->invert_x = of_property_read_bool(np, "touchscreen-inverted-x");
236 data->invert_y = of_property_read_bool(np, "touchscreen-inverted-y");
237 data->swap_x_y = of_property_read_bool(np, "touchscreen-swapped-x-y");
238
239 input = devm_input_allocate_device(dev);
240 if (!input)
241 return -ENOMEM;
242
243 input->name = client->name;
244 input->id.bustype = BUS_I2C;
245 input->open = icn8318_start;
246 input->close = icn8318_stop;
247 input->dev.parent = dev;
248
249 if (!data->swap_x_y) {
250 input_set_abs_params(input, ABS_MT_POSITION_X, 0,
251 data->max_x, fuzz_x, 0);
252 input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
253 data->max_y, fuzz_y, 0);
254 } else {
255 input_set_abs_params(input, ABS_MT_POSITION_X, 0,
256 data->max_y, fuzz_y, 0);
257 input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
258 data->max_x, fuzz_x, 0);
259 }
260
261 error = input_mt_init_slots(input, ICN8318_MAX_TOUCHES,
262 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
263 if (error)
264 return error;
265
266 data->client = client;
267 data->input = input;
268 input_set_drvdata(input, data);
269
270 error = devm_request_threaded_irq(dev, client->irq, NULL, icn8318_irq,
271 IRQF_ONESHOT, client->name, data);
272 if (error) {
273 dev_err(dev, "Error requesting irq: %d\n", error);
274 return error;
275 }
276
277
278 icn8318_stop(data->input);
279
280 error = input_register_device(input);
281 if (error)
282 return error;
283
284 i2c_set_clientdata(client, data);
285
286 return 0;
287}
288
289static const struct of_device_id icn8318_of_match[] = {
290 { .compatible = "chipone,icn8318" },
291 { }
292};
293MODULE_DEVICE_TABLE(of, icn8318_of_match);
294
295
296static const struct i2c_device_id icn8318_i2c_id[] = {
297 { },
298};
299MODULE_DEVICE_TABLE(i2c, icn8318_i2c_id);
300
301static struct i2c_driver icn8318_driver = {
302 .driver = {
303 .name = "chipone_icn8318",
304 .pm = &icn8318_pm_ops,
305 .of_match_table = icn8318_of_match,
306 },
307 .probe = icn8318_probe,
308 .id_table = icn8318_i2c_id,
309};
310
311module_i2c_driver(icn8318_driver);
312
313MODULE_DESCRIPTION("ChipOne icn8318 I2C Touchscreen Driver");
314MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
315MODULE_LICENSE("GPL");
316
