1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35#include <linux/module.h>
36#include <linux/i2c.h>
37#include <linux/interrupt.h>
38#include <linux/input.h>
39#include <linux/slab.h>
40#include <linux/bitops.h>
41
42
43#define GENERNAL_STATUS_REG 0x00
44#define GENERNAL_CONF_REG 0x01
45#define MESURE_RES_CONF_REG 0x02
46#define MESURE_AVER_CONF_REG 0x03
47#define ADC_SAMPLE_TIME_CONF_REG 0x04
48#define PANEL_SETUPTIME_CONF_REG 0x05
49#define DELAY_CONVERSION_CONF_REG 0x06
50#define TOUCH_DETECT_PULLUP_CONF_REG 0x07
51#define AUTO_MODE_TIME_CONF_REG 0x08
52#define APERTURE_CONF_REG 0x09
53#define AUX_MESURE_CONF_REG 0x0a
54#define OP_MODE_CONF_REG 0x0b
55
56
57#define FIFO_RD_CMD (0x50 << 1)
58#define MAX11801_FIFO_INT (1 << 2)
59#define MAX11801_FIFO_OVERFLOW (1 << 3)
60
61#define XY_BUFSIZE 4
62#define XY_BUF_OFFSET 4
63
64#define MAX11801_MAX_X 0xfff
65#define MAX11801_MAX_Y 0xfff
66
67#define MEASURE_TAG_OFFSET 2
68#define MEASURE_TAG_MASK (3 << MEASURE_TAG_OFFSET)
69#define EVENT_TAG_OFFSET 0
70#define EVENT_TAG_MASK (3 << EVENT_TAG_OFFSET)
71#define MEASURE_X_TAG (0 << MEASURE_TAG_OFFSET)
72#define MEASURE_Y_TAG (1 << MEASURE_TAG_OFFSET)
73
74
75enum {
76 EVENT_INIT,
77 EVENT_MIDDLE,
78 EVENT_RELEASE,
79 EVENT_FIFO_END
80};
81
82struct max11801_data {
83 struct i2c_client *client;
84 struct input_dev *input_dev;
85};
86
87static u8 read_register(struct i2c_client *client, int addr)
88{
89
90 return i2c_smbus_read_byte_data(client, addr << 1);
91}
92
93static int max11801_write_reg(struct i2c_client *client, int addr, int data)
94{
95
96 return i2c_smbus_write_byte_data(client, addr << 1, data);
97}
98
99static irqreturn_t max11801_ts_interrupt(int irq, void *dev_id)
100{
101 struct max11801_data *data = dev_id;
102 struct i2c_client *client = data->client;
103 int status, i, ret;
104 u8 buf[XY_BUFSIZE];
105 int x = -1;
106 int y = -1;
107
108 status = read_register(data->client, GENERNAL_STATUS_REG);
109
110 if (status & (MAX11801_FIFO_INT | MAX11801_FIFO_OVERFLOW)) {
111 status = read_register(data->client, GENERNAL_STATUS_REG);
112
113 ret = i2c_smbus_read_i2c_block_data(client, FIFO_RD_CMD,
114 XY_BUFSIZE, buf);
115
116
117
118
119
120 if (ret < XY_BUFSIZE)
121 goto out;
122
123 for (i = 0; i < XY_BUFSIZE; i += XY_BUFSIZE / 2) {
124 if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_X_TAG)
125 x = (buf[i] << XY_BUF_OFFSET) +
126 (buf[i + 1] >> XY_BUF_OFFSET);
127 else if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_Y_TAG)
128 y = (buf[i] << XY_BUF_OFFSET) +
129 (buf[i + 1] >> XY_BUF_OFFSET);
130 }
131
132 if ((buf[1] & EVENT_TAG_MASK) != (buf[3] & EVENT_TAG_MASK))
133 goto out;
134
135 switch (buf[1] & EVENT_TAG_MASK) {
136 case EVENT_INIT:
137
138 case EVENT_MIDDLE:
139 input_report_abs(data->input_dev, ABS_X, x);
140 input_report_abs(data->input_dev, ABS_Y, y);
141 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 1);
142 input_sync(data->input_dev);
143 break;
144
145 case EVENT_RELEASE:
146 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 0);
147 input_sync(data->input_dev);
148 break;
149
150 case EVENT_FIFO_END:
151 break;
152 }
153 }
154out:
155 return IRQ_HANDLED;
156}
157
158static void max11801_ts_phy_init(struct max11801_data *data)
159{
160 struct i2c_client *client = data->client;
161
162
163 max11801_write_reg(client, MESURE_AVER_CONF_REG, 0xff);
164
165 max11801_write_reg(client, PANEL_SETUPTIME_CONF_REG, 0x11);
166
167 max11801_write_reg(client, TOUCH_DETECT_PULLUP_CONF_REG, 0x10);
168
169 max11801_write_reg(client, AUTO_MODE_TIME_CONF_REG, 0xaa);
170
171 max11801_write_reg(client, APERTURE_CONF_REG, 0x33);
172
173 max11801_write_reg(client, OP_MODE_CONF_REG, 0x36);
174}
175
176static int max11801_ts_probe(struct i2c_client *client,
177 const struct i2c_device_id *id)
178{
179 struct max11801_data *data;
180 struct input_dev *input_dev;
181 int error;
182
183 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
184 input_dev = devm_input_allocate_device(&client->dev);
185 if (!data || !input_dev) {
186 dev_err(&client->dev, "Failed to allocate memory\n");
187 return -ENOMEM;
188 }
189
190 data->client = client;
191 data->input_dev = input_dev;
192
193 input_dev->name = "max11801_ts";
194 input_dev->id.bustype = BUS_I2C;
195 input_dev->dev.parent = &client->dev;
196
197 __set_bit(EV_ABS, input_dev->evbit);
198 __set_bit(EV_KEY, input_dev->evbit);
199 __set_bit(BTN_TOUCH, input_dev->keybit);
200 input_set_abs_params(input_dev, ABS_X, 0, MAX11801_MAX_X, 0, 0);
201 input_set_abs_params(input_dev, ABS_Y, 0, MAX11801_MAX_Y, 0, 0);
202 input_set_drvdata(input_dev, data);
203
204 max11801_ts_phy_init(data);
205
206 error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
207 max11801_ts_interrupt,
208 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
209 "max11801_ts", data);
210 if (error) {
211 dev_err(&client->dev, "Failed to register interrupt\n");
212 return error;
213 }
214
215 error = input_register_device(data->input_dev);
216 if (error)
217 return error;
218
219 i2c_set_clientdata(client, data);
220 return 0;
221}
222
223static const struct i2c_device_id max11801_ts_id[] = {
224 {"max11801", 0},
225 { }
226};
227MODULE_DEVICE_TABLE(i2c, max11801_ts_id);
228
229static struct i2c_driver max11801_ts_driver = {
230 .driver = {
231 .name = "max11801_ts",
232 },
233 .id_table = max11801_ts_id,
234 .probe = max11801_ts_probe,
235};
236
237module_i2c_driver(max11801_ts_driver);
238
239MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
240MODULE_DESCRIPTION("Touchscreen driver for MAXI MAX11801 controller");
241MODULE_LICENSE("GPL");
242
