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17#include <linux/module.h>
18#include <linux/i2c.h>
19#include <linux/interrupt.h>
20#include <linux/input.h>
21#include <linux/irq.h>
22#include <linux/gpio.h>
23#include <linux/delay.h>
24#include <linux/slab.h>
25#include <linux/bitops.h>
26#include <linux/input/mt.h>
27#include <linux/of_gpio.h>
28
29
30
31
32
33
34#define REPORT_MODE_MOUSE 0x1
35
36
37
38
39
40#define REPORT_MODE_VENDOR 0x3
41
42#define REPORT_MODE_MTTOUCH 0x4
43
44#define MAX_SUPPORT_POINTS 5
45
46#define EVENT_VALID_OFFSET 7
47#define EVENT_VALID_MASK (0x1 << EVENT_VALID_OFFSET)
48#define EVENT_ID_OFFSET 2
49#define EVENT_ID_MASK (0xf << EVENT_ID_OFFSET)
50#define EVENT_IN_RANGE (0x1 << 1)
51#define EVENT_DOWN_UP (0X1 << 0)
52
53#define MAX_I2C_DATA_LEN 10
54
55#define EGALAX_MAX_X 32760
56#define EGALAX_MAX_Y 32760
57#define EGALAX_MAX_TRIES 100
58
59struct egalax_ts {
60 struct i2c_client *client;
61 struct input_dev *input_dev;
62};
63
64static irqreturn_t egalax_ts_interrupt(int irq, void *dev_id)
65{
66 struct egalax_ts *ts = dev_id;
67 struct input_dev *input_dev = ts->input_dev;
68 struct i2c_client *client = ts->client;
69 u8 buf[MAX_I2C_DATA_LEN];
70 int id, ret, x, y, z;
71 int tries = 0;
72 bool down, valid;
73 u8 state;
74
75 do {
76 ret = i2c_master_recv(client, buf, MAX_I2C_DATA_LEN);
77 } while (ret == -EAGAIN && tries++ < EGALAX_MAX_TRIES);
78
79 if (ret < 0)
80 return IRQ_HANDLED;
81
82 if (buf[0] != REPORT_MODE_MTTOUCH) {
83
84 return IRQ_HANDLED;
85 }
86
87 state = buf[1];
88 x = (buf[3] << 8) | buf[2];
89 y = (buf[5] << 8) | buf[4];
90 z = (buf[7] << 8) | buf[6];
91
92 valid = state & EVENT_VALID_MASK;
93 id = (state & EVENT_ID_MASK) >> EVENT_ID_OFFSET;
94 down = state & EVENT_DOWN_UP;
95
96 if (!valid || id > MAX_SUPPORT_POINTS) {
97 dev_dbg(&client->dev, "point invalid\n");
98 return IRQ_HANDLED;
99 }
100
101 input_mt_slot(input_dev, id);
102 input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, down);
103
104 dev_dbg(&client->dev, "%s id:%d x:%d y:%d z:%d",
105 down ? "down" : "up", id, x, y, z);
106
107 if (down) {
108 input_report_abs(input_dev, ABS_MT_POSITION_X, x);
109 input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
110 input_report_abs(input_dev, ABS_MT_PRESSURE, z);
111 }
112
113 input_mt_report_pointer_emulation(input_dev, true);
114 input_sync(input_dev);
115
116 return IRQ_HANDLED;
117}
118
119
120static int egalax_wake_up_device(struct i2c_client *client)
121{
122 struct device_node *np = client->dev.of_node;
123 int gpio;
124 int ret;
125
126 if (!np)
127 return -ENODEV;
128
129 gpio = of_get_named_gpio(np, "wakeup-gpios", 0);
130 if (!gpio_is_valid(gpio))
131 return -ENODEV;
132
133 ret = gpio_request(gpio, "egalax_irq");
134 if (ret < 0) {
135 dev_err(&client->dev,
136 "request gpio failed, cannot wake up controller: %d\n",
137 ret);
138 return ret;
139 }
140
141
142 gpio_direction_output(gpio, 0);
143 gpio_set_value(gpio, 1);
144
145
146 gpio_direction_input(gpio);
147 gpio_free(gpio);
148
149 return 0;
150}
151
152static int egalax_firmware_version(struct i2c_client *client)
153{
154 static const u8 cmd[MAX_I2C_DATA_LEN] = { 0x03, 0x03, 0xa, 0x01, 0x41 };
155 int ret;
156
157 ret = i2c_master_send(client, cmd, MAX_I2C_DATA_LEN);
158 if (ret < 0)
159 return ret;
160
161 return 0;
162}
163
164static int egalax_ts_probe(struct i2c_client *client,
165 const struct i2c_device_id *id)
166{
167 struct egalax_ts *ts;
168 struct input_dev *input_dev;
169 int error;
170
171 ts = devm_kzalloc(&client->dev, sizeof(struct egalax_ts), GFP_KERNEL);
172 if (!ts) {
173 dev_err(&client->dev, "Failed to allocate memory\n");
174 return -ENOMEM;
175 }
176
177 input_dev = devm_input_allocate_device(&client->dev);
178 if (!input_dev) {
179 dev_err(&client->dev, "Failed to allocate memory\n");
180 return -ENOMEM;
181 }
182
183 ts->client = client;
184 ts->input_dev = input_dev;
185
186
187 error = egalax_wake_up_device(client);
188 if (error) {
189 dev_err(&client->dev, "Failed to wake up the controller\n");
190 return error;
191 }
192
193 error = egalax_firmware_version(client);
194 if (error < 0) {
195 dev_err(&client->dev, "Failed to read firmware version\n");
196 return error;
197 }
198
199 input_dev->name = "EETI eGalax Touch Screen";
200 input_dev->id.bustype = BUS_I2C;
201
202 __set_bit(EV_ABS, input_dev->evbit);
203 __set_bit(EV_KEY, input_dev->evbit);
204 __set_bit(BTN_TOUCH, input_dev->keybit);
205
206 input_set_abs_params(input_dev, ABS_X, 0, EGALAX_MAX_X, 0, 0);
207 input_set_abs_params(input_dev, ABS_Y, 0, EGALAX_MAX_Y, 0, 0);
208 input_set_abs_params(input_dev,
209 ABS_MT_POSITION_X, 0, EGALAX_MAX_X, 0, 0);
210 input_set_abs_params(input_dev,
211 ABS_MT_POSITION_Y, 0, EGALAX_MAX_Y, 0, 0);
212 input_mt_init_slots(input_dev, MAX_SUPPORT_POINTS, 0);
213
214 error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
215 egalax_ts_interrupt,
216 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
217 "egalax_ts", ts);
218 if (error < 0) {
219 dev_err(&client->dev, "Failed to register interrupt\n");
220 return error;
221 }
222
223 error = input_register_device(ts->input_dev);
224 if (error)
225 return error;
226
227 return 0;
228}
229
230static const struct i2c_device_id egalax_ts_id[] = {
231 { "egalax_ts", 0 },
232 { }
233};
234MODULE_DEVICE_TABLE(i2c, egalax_ts_id);
235
236static int __maybe_unused egalax_ts_suspend(struct device *dev)
237{
238 static const u8 suspend_cmd[MAX_I2C_DATA_LEN] = {
239 0x3, 0x6, 0xa, 0x3, 0x36, 0x3f, 0x2, 0, 0, 0
240 };
241 struct i2c_client *client = to_i2c_client(dev);
242 int ret;
243
244 if (device_may_wakeup(dev))
245 return enable_irq_wake(client->irq);
246
247 ret = i2c_master_send(client, suspend_cmd, MAX_I2C_DATA_LEN);
248 return ret > 0 ? 0 : ret;
249}
250
251static int __maybe_unused egalax_ts_resume(struct device *dev)
252{
253 struct i2c_client *client = to_i2c_client(dev);
254
255 if (device_may_wakeup(dev))
256 return disable_irq_wake(client->irq);
257
258 return egalax_wake_up_device(client);
259}
260
261static SIMPLE_DEV_PM_OPS(egalax_ts_pm_ops, egalax_ts_suspend, egalax_ts_resume);
262
263static const struct of_device_id egalax_ts_dt_ids[] = {
264 { .compatible = "eeti,egalax_ts" },
265 { }
266};
267MODULE_DEVICE_TABLE(of, egalax_ts_dt_ids);
268
269static struct i2c_driver egalax_ts_driver = {
270 .driver = {
271 .name = "egalax_ts",
272 .pm = &egalax_ts_pm_ops,
273 .of_match_table = egalax_ts_dt_ids,
274 },
275 .id_table = egalax_ts_id,
276 .probe = egalax_ts_probe,
277};
278
279module_i2c_driver(egalax_ts_driver);
280
281MODULE_AUTHOR("Freescale Semiconductor, Inc.");
282MODULE_DESCRIPTION("Touchscreen driver for EETI eGalax touch controller");
283MODULE_LICENSE("GPL");
284
