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