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30#include <linux/input.h>
31#include <linux/module.h>
32#include <linux/of.h>
33#include <linux/i2c.h>
34#include <linux/interrupt.h>
35#include <linux/irq.h>
36
37
38#define I2C_REG_TOUCH0 0x00
39#define I2C_REG_TOUCH1 0x01
40#define I2C_REG_CHANMASK 0x04
41#define I2C_REG_IRQMASK 0x22
42#define I2C_REG_IRQSRC 0x23
43#define I2C_REG_SOFTRESET 0x3f
44
45
46#define CMD_READ_REGISTER 0x40
47#define CMD_MANUAL 0xc0
48#define CMD_PENTRG 0xe0
49
50
51#define SOFTRESET_VALUE 0xde
52
53
54#define IRQ_PENTOUCH_TOUCHCONVDONE 0x08
55#define IRQ_PENRELEASE 0x04
56
57
58#define CONDIRQ 0x20
59#define FILT_7SA 0x03
60
61
62#define CONV_X 0x80
63#define CONV_Y 0x40
64
65
66#define RATE_MANUAL 0x00
67#define RATE_5000CPS 0xf0
68
69
70#define POWDLY_1_1MS 0x0b
71
72#define MAX_12BIT ((1 << 12) - 1)
73
74struct sx8654 {
75 struct input_dev *input;
76 struct i2c_client *client;
77};
78
79static irqreturn_t sx8654_irq(int irq, void *handle)
80{
81 struct sx8654 *sx8654 = handle;
82 int irqsrc;
83 u8 data[4];
84 unsigned int x, y;
85 int retval;
86
87 irqsrc = i2c_smbus_read_byte_data(sx8654->client,
88 CMD_READ_REGISTER | I2C_REG_IRQSRC);
89 dev_dbg(&sx8654->client->dev, "irqsrc = 0x%x", irqsrc);
90
91 if (irqsrc < 0)
92 goto out;
93
94 if (irqsrc & IRQ_PENRELEASE) {
95 dev_dbg(&sx8654->client->dev, "pen release interrupt");
96
97 input_report_key(sx8654->input, BTN_TOUCH, 0);
98 input_sync(sx8654->input);
99 }
100
101 if (irqsrc & IRQ_PENTOUCH_TOUCHCONVDONE) {
102 dev_dbg(&sx8654->client->dev, "pen touch interrupt");
103
104 retval = i2c_master_recv(sx8654->client, data, sizeof(data));
105 if (retval != sizeof(data))
106 goto out;
107
108
109 if (unlikely(data[0] & 0x80 || data[2] & 0x80))
110 goto out;
111
112 x = ((data[0] & 0xf) << 8) | (data[1]);
113 y = ((data[2] & 0xf) << 8) | (data[3]);
114
115 input_report_abs(sx8654->input, ABS_X, x);
116 input_report_abs(sx8654->input, ABS_Y, y);
117 input_report_key(sx8654->input, BTN_TOUCH, 1);
118 input_sync(sx8654->input);
119
120 dev_dbg(&sx8654->client->dev, "point(%4d,%4d)\n", x, y);
121 }
122
123out:
124 return IRQ_HANDLED;
125}
126
127static int sx8654_open(struct input_dev *dev)
128{
129 struct sx8654 *sx8654 = input_get_drvdata(dev);
130 struct i2c_client *client = sx8654->client;
131 int error;
132
133
134 error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0,
135 RATE_5000CPS | POWDLY_1_1MS);
136 if (error) {
137 dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
138 return error;
139 }
140
141 error = i2c_smbus_write_byte(client, CMD_PENTRG);
142 if (error) {
143 dev_err(&client->dev, "writing command CMD_PENTRG failed");
144 return error;
145 }
146
147 enable_irq(client->irq);
148
149 return 0;
150}
151
152static void sx8654_close(struct input_dev *dev)
153{
154 struct sx8654 *sx8654 = input_get_drvdata(dev);
155 struct i2c_client *client = sx8654->client;
156 int error;
157
158 disable_irq(client->irq);
159
160
161 error = i2c_smbus_write_byte(client, CMD_MANUAL);
162 if (error) {
163 dev_err(&client->dev, "writing command CMD_MANUAL failed");
164 return;
165 }
166
167 error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH0, 0);
168 if (error) {
169 dev_err(&client->dev, "writing to I2C_REG_TOUCH0 failed");
170 return;
171 }
172}
173
174static int sx8654_probe(struct i2c_client *client,
175 const struct i2c_device_id *id)
176{
177 struct sx8654 *sx8654;
178 struct input_dev *input;
179 int error;
180
181 if (!i2c_check_functionality(client->adapter,
182 I2C_FUNC_SMBUS_READ_WORD_DATA))
183 return -ENXIO;
184
185 sx8654 = devm_kzalloc(&client->dev, sizeof(*sx8654), GFP_KERNEL);
186 if (!sx8654)
187 return -ENOMEM;
188
189 input = devm_input_allocate_device(&client->dev);
190 if (!input)
191 return -ENOMEM;
192
193 input->name = "SX8654 I2C Touchscreen";
194 input->id.bustype = BUS_I2C;
195 input->dev.parent = &client->dev;
196 input->open = sx8654_open;
197 input->close = sx8654_close;
198
199 __set_bit(INPUT_PROP_DIRECT, input->propbit);
200 input_set_capability(input, EV_KEY, BTN_TOUCH);
201 input_set_abs_params(input, ABS_X, 0, MAX_12BIT, 0, 0);
202 input_set_abs_params(input, ABS_Y, 0, MAX_12BIT, 0, 0);
203
204 sx8654->client = client;
205 sx8654->input = input;
206
207 input_set_drvdata(sx8654->input, sx8654);
208
209 error = i2c_smbus_write_byte_data(client, I2C_REG_SOFTRESET,
210 SOFTRESET_VALUE);
211 if (error) {
212 dev_err(&client->dev, "writing softreset value failed");
213 return error;
214 }
215
216 error = i2c_smbus_write_byte_data(client, I2C_REG_CHANMASK,
217 CONV_X | CONV_Y);
218 if (error) {
219 dev_err(&client->dev, "writing to I2C_REG_CHANMASK failed");
220 return error;
221 }
222
223 error = i2c_smbus_write_byte_data(client, I2C_REG_IRQMASK,
224 IRQ_PENTOUCH_TOUCHCONVDONE |
225 IRQ_PENRELEASE);
226 if (error) {
227 dev_err(&client->dev, "writing to I2C_REG_IRQMASK failed");
228 return error;
229 }
230
231 error = i2c_smbus_write_byte_data(client, I2C_REG_TOUCH1,
232 CONDIRQ | FILT_7SA);
233 if (error) {
234 dev_err(&client->dev, "writing to I2C_REG_TOUCH1 failed");
235 return error;
236 }
237
238 error = devm_request_threaded_irq(&client->dev, client->irq,
239 NULL, sx8654_irq,
240 IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
241 client->name, sx8654);
242 if (error) {
243 dev_err(&client->dev,
244 "Failed to enable IRQ %d, error: %d\n",
245 client->irq, error);
246 return error;
247 }
248
249
250 disable_irq(client->irq);
251
252 error = input_register_device(sx8654->input);
253 if (error)
254 return error;
255
256 return 0;
257}
258
259#ifdef CONFIG_OF
260static const struct of_device_id sx8654_of_match[] = {
261 { .compatible = "semtech,sx8654", },
262 { },
263};
264MODULE_DEVICE_TABLE(of, sx8654_of_match);
265#endif
266
267static const struct i2c_device_id sx8654_id_table[] = {
268 { "semtech_sx8654", 0 },
269 { },
270};
271MODULE_DEVICE_TABLE(i2c, sx8654_id_table);
272
273static struct i2c_driver sx8654_driver = {
274 .driver = {
275 .name = "sx8654",
276 .of_match_table = of_match_ptr(sx8654_of_match),
277 },
278 .id_table = sx8654_id_table,
279 .probe = sx8654_probe,
280};
281module_i2c_driver(sx8654_driver);
282
283MODULE_AUTHOR("Sébastien Szymanski <sebastien.szymanski@armadeus.com>");
284MODULE_DESCRIPTION("Semtech SX8654 I2C Touchscreen Driver");
285MODULE_LICENSE("GPL");
286
