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31#include <linux/module.h>
32#include <linux/i2c.h>
33#include <linux/interrupt.h>
34#include <linux/input.h>
35#include <linux/slab.h>
36#include <linux/bitops.h>
37
38
39#define GENERNAL_STATUS_REG 0x00
40#define GENERNAL_CONF_REG 0x01
41#define MESURE_RES_CONF_REG 0x02
42#define MESURE_AVER_CONF_REG 0x03
43#define ADC_SAMPLE_TIME_CONF_REG 0x04
44#define PANEL_SETUPTIME_CONF_REG 0x05
45#define DELAY_CONVERSION_CONF_REG 0x06
46#define TOUCH_DETECT_PULLUP_CONF_REG 0x07
47#define AUTO_MODE_TIME_CONF_REG 0x08
48#define APERTURE_CONF_REG 0x09
49#define AUX_MESURE_CONF_REG 0x0a
50#define OP_MODE_CONF_REG 0x0b
51
52
53#define FIFO_RD_CMD (0x50 << 1)
54#define MAX11801_FIFO_INT (1 << 2)
55#define MAX11801_FIFO_OVERFLOW (1 << 3)
56
57#define XY_BUFSIZE 4
58#define XY_BUF_OFFSET 4
59
60#define MAX11801_MAX_X 0xfff
61#define MAX11801_MAX_Y 0xfff
62
63#define MEASURE_TAG_OFFSET 2
64#define MEASURE_TAG_MASK (3 << MEASURE_TAG_OFFSET)
65#define EVENT_TAG_OFFSET 0
66#define EVENT_TAG_MASK (3 << EVENT_TAG_OFFSET)
67#define MEASURE_X_TAG (0 << MEASURE_TAG_OFFSET)
68#define MEASURE_Y_TAG (1 << MEASURE_TAG_OFFSET)
69
70
71enum {
72 EVENT_INIT,
73 EVENT_MIDDLE,
74 EVENT_RELEASE,
75 EVENT_FIFO_END
76};
77
78struct max11801_data {
79 struct i2c_client *client;
80 struct input_dev *input_dev;
81};
82
83static u8 read_register(struct i2c_client *client, int addr)
84{
85
86 return i2c_smbus_read_byte_data(client, addr << 1);
87}
88
89static int max11801_write_reg(struct i2c_client *client, int addr, int data)
90{
91
92 return i2c_smbus_write_byte_data(client, addr << 1, data);
93}
94
95static irqreturn_t max11801_ts_interrupt(int irq, void *dev_id)
96{
97 struct max11801_data *data = dev_id;
98 struct i2c_client *client = data->client;
99 int status, i, ret;
100 u8 buf[XY_BUFSIZE];
101 int x = -1;
102 int y = -1;
103
104 status = read_register(data->client, GENERNAL_STATUS_REG);
105
106 if (status & (MAX11801_FIFO_INT | MAX11801_FIFO_OVERFLOW)) {
107 status = read_register(data->client, GENERNAL_STATUS_REG);
108
109 ret = i2c_smbus_read_i2c_block_data(client, FIFO_RD_CMD,
110 XY_BUFSIZE, buf);
111
112
113
114
115
116 if (ret < XY_BUFSIZE)
117 goto out;
118
119 for (i = 0; i < XY_BUFSIZE; i += XY_BUFSIZE / 2) {
120 if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_X_TAG)
121 x = (buf[i] << XY_BUF_OFFSET) +
122 (buf[i + 1] >> XY_BUF_OFFSET);
123 else if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_Y_TAG)
124 y = (buf[i] << XY_BUF_OFFSET) +
125 (buf[i + 1] >> XY_BUF_OFFSET);
126 }
127
128 if ((buf[1] & EVENT_TAG_MASK) != (buf[3] & EVENT_TAG_MASK))
129 goto out;
130
131 switch (buf[1] & EVENT_TAG_MASK) {
132 case EVENT_INIT:
133
134 case EVENT_MIDDLE:
135 input_report_abs(data->input_dev, ABS_X, x);
136 input_report_abs(data->input_dev, ABS_Y, y);
137 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 1);
138 input_sync(data->input_dev);
139 break;
140
141 case EVENT_RELEASE:
142 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 0);
143 input_sync(data->input_dev);
144 break;
145
146 case EVENT_FIFO_END:
147 break;
148 }
149 }
150out:
151 return IRQ_HANDLED;
152}
153
154static void max11801_ts_phy_init(struct max11801_data *data)
155{
156 struct i2c_client *client = data->client;
157
158
159 max11801_write_reg(client, MESURE_AVER_CONF_REG, 0xff);
160
161 max11801_write_reg(client, PANEL_SETUPTIME_CONF_REG, 0x11);
162
163 max11801_write_reg(client, TOUCH_DETECT_PULLUP_CONF_REG, 0x10);
164
165 max11801_write_reg(client, AUTO_MODE_TIME_CONF_REG, 0xaa);
166
167 max11801_write_reg(client, APERTURE_CONF_REG, 0x33);
168
169 max11801_write_reg(client, OP_MODE_CONF_REG, 0x36);
170}
171
172static int max11801_ts_probe(struct i2c_client *client,
173 const struct i2c_device_id *id)
174{
175 struct max11801_data *data;
176 struct input_dev *input_dev;
177 int error;
178
179 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
180 input_dev = devm_input_allocate_device(&client->dev);
181 if (!data || !input_dev) {
182 dev_err(&client->dev, "Failed to allocate memory\n");
183 return -ENOMEM;
184 }
185
186 data->client = client;
187 data->input_dev = input_dev;
188
189 input_dev->name = "max11801_ts";
190 input_dev->id.bustype = BUS_I2C;
191 input_dev->dev.parent = &client->dev;
192
193 __set_bit(EV_ABS, input_dev->evbit);
194 __set_bit(EV_KEY, input_dev->evbit);
195 __set_bit(BTN_TOUCH, input_dev->keybit);
196 input_set_abs_params(input_dev, ABS_X, 0, MAX11801_MAX_X, 0, 0);
197 input_set_abs_params(input_dev, ABS_Y, 0, MAX11801_MAX_Y, 0, 0);
198
199 max11801_ts_phy_init(data);
200
201 error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
202 max11801_ts_interrupt,
203 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
204 "max11801_ts", data);
205 if (error) {
206 dev_err(&client->dev, "Failed to register interrupt\n");
207 return error;
208 }
209
210 error = input_register_device(data->input_dev);
211 if (error)
212 return error;
213
214 return 0;
215}
216
217static const struct i2c_device_id max11801_ts_id[] = {
218 {"max11801", 0},
219 { }
220};
221MODULE_DEVICE_TABLE(i2c, max11801_ts_id);
222
223static const struct of_device_id max11801_ts_dt_ids[] = {
224 { .compatible = "maxim,max11801" },
225 { }
226};
227MODULE_DEVICE_TABLE(of, max11801_ts_dt_ids);
228
229static struct i2c_driver max11801_ts_driver = {
230 .driver = {
231 .name = "max11801_ts",
232 .of_match_table = max11801_ts_dt_ids,
233 },
234 .id_table = max11801_ts_id,
235 .probe = max11801_ts_probe,
236};
237
238module_i2c_driver(max11801_ts_driver);
239
240MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
241MODULE_DESCRIPTION("Touchscreen driver for MAXI MAX11801 controller");
242MODULE_LICENSE("GPL");
243
