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1/*
2 * Driver for MAXI MAX11801 - A Resistive touch screen controller with
3 * i2c interface
4 *
5 * Copyright (C) 2011 Freescale Semiconductor, Inc.
6 * Author: Zhang Jiejing <jiejing.zhang@freescale.com>
7 *
8 * Based on mcs5000_ts.c
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 */
15
16/*
17 * This driver aims to support the series of MAXI touch chips max11801
18 * through max11803. The main difference between these 4 chips can be
19 * found in the table below:
20 * -----------------------------------------------------
21 * | CHIP | AUTO MODE SUPPORT(FIFO) | INTERFACE |
22 * |----------------------------------------------------|
23 * | max11800 | YES | SPI |
24 * | max11801 | YES | I2C |
25 * | max11802 | NO | SPI |
26 * | max11803 | NO | I2C |
27 * ------------------------------------------------------
28 *
29 * Currently, this driver only supports max11801.
30 *
31 * Data Sheet:
32 * http://www.maxim-ic.com/datasheet/index.mvp/id/5943
33 */
34
35#include <linux/module.h>
36#include <linux/init.h>
37#include <linux/i2c.h>
38#include <linux/interrupt.h>
39#include <linux/input.h>
40#include <linux/slab.h>
41#include <linux/bitops.h>
42
43/* Register Address define */
44#define GENERNAL_STATUS_REG 0x00
45#define GENERNAL_CONF_REG 0x01
46#define MESURE_RES_CONF_REG 0x02
47#define MESURE_AVER_CONF_REG 0x03
48#define ADC_SAMPLE_TIME_CONF_REG 0x04
49#define PANEL_SETUPTIME_CONF_REG 0x05
50#define DELAY_CONVERSION_CONF_REG 0x06
51#define TOUCH_DETECT_PULLUP_CONF_REG 0x07
52#define AUTO_MODE_TIME_CONF_REG 0x08 /* only for max11800/max11801 */
53#define APERTURE_CONF_REG 0x09 /* only for max11800/max11801 */
54#define AUX_MESURE_CONF_REG 0x0a
55#define OP_MODE_CONF_REG 0x0b
56
57/* FIFO is found only in max11800 and max11801 */
58#define FIFO_RD_CMD (0x50 << 1)
59#define MAX11801_FIFO_INT (1 << 2)
60#define MAX11801_FIFO_OVERFLOW (1 << 3)
61
62#define XY_BUFSIZE 4
63#define XY_BUF_OFFSET 4
64
65#define MAX11801_MAX_X 0xfff
66#define MAX11801_MAX_Y 0xfff
67
68#define MEASURE_TAG_OFFSET 2
69#define MEASURE_TAG_MASK (3 << MEASURE_TAG_OFFSET)
70#define EVENT_TAG_OFFSET 0
71#define EVENT_TAG_MASK (3 << EVENT_TAG_OFFSET)
72#define MEASURE_X_TAG (0 << MEASURE_TAG_OFFSET)
73#define MEASURE_Y_TAG (1 << MEASURE_TAG_OFFSET)
74
75/* These are the state of touch event state machine */
76enum {
77 EVENT_INIT,
78 EVENT_MIDDLE,
79 EVENT_RELEASE,
80 EVENT_FIFO_END
81};
82
83struct max11801_data {
84 struct i2c_client *client;
85 struct input_dev *input_dev;
86};
87
88static u8 read_register(struct i2c_client *client, int addr)
89{
90 /* XXX: The chip ignores LSB of register address */
91 return i2c_smbus_read_byte_data(client, addr << 1);
92}
93
94static int max11801_write_reg(struct i2c_client *client, int addr, int data)
95{
96 /* XXX: The chip ignores LSB of register address */
97 return i2c_smbus_write_byte_data(client, addr << 1, data);
98}
99
100static irqreturn_t max11801_ts_interrupt(int irq, void *dev_id)
101{
102 struct max11801_data *data = dev_id;
103 struct i2c_client *client = data->client;
104 int status, i, ret;
105 u8 buf[XY_BUFSIZE];
106 int x = -1;
107 int y = -1;
108
109 status = read_register(data->client, GENERNAL_STATUS_REG);
110
111 if (status & (MAX11801_FIFO_INT | MAX11801_FIFO_OVERFLOW)) {
112 status = read_register(data->client, GENERNAL_STATUS_REG);
113
114 ret = i2c_smbus_read_i2c_block_data(client, FIFO_RD_CMD,
115 XY_BUFSIZE, buf);
116
117 /*
118 * We should get 4 bytes buffer that contains X,Y
119 * and event tag
120 */
121 if (ret < XY_BUFSIZE)
122 goto out;
123
124 for (i = 0; i < XY_BUFSIZE; i += XY_BUFSIZE / 2) {
125 if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_X_TAG)
126 x = (buf[i] << XY_BUF_OFFSET) +
127 (buf[i + 1] >> XY_BUF_OFFSET);
128 else if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_Y_TAG)
129 y = (buf[i] << XY_BUF_OFFSET) +
130 (buf[i + 1] >> XY_BUF_OFFSET);
131 }
132
133 if ((buf[1] & EVENT_TAG_MASK) != (buf[3] & EVENT_TAG_MASK))
134 goto out;
135
136 switch (buf[1] & EVENT_TAG_MASK) {
137 case EVENT_INIT:
138 /* fall through */
139 case EVENT_MIDDLE:
140 input_report_abs(data->input_dev, ABS_X, x);
141 input_report_abs(data->input_dev, ABS_Y, y);
142 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 1);
143 input_sync(data->input_dev);
144 break;
145
146 case EVENT_RELEASE:
147 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 0);
148 input_sync(data->input_dev);
149 break;
150
151 case EVENT_FIFO_END:
152 break;
153 }
154 }
155out:
156 return IRQ_HANDLED;
157}
158
159static void __devinit max11801_ts_phy_init(struct max11801_data *data)
160{
161 struct i2c_client *client = data->client;
162
163 /* Average X,Y, take 16 samples, average eight media sample */
164 max11801_write_reg(client, MESURE_AVER_CONF_REG, 0xff);
165 /* X,Y panel setup time set to 20us */
166 max11801_write_reg(client, PANEL_SETUPTIME_CONF_REG, 0x11);
167 /* Rough pullup time (2uS), Fine pullup time (10us) */
168 max11801_write_reg(client, TOUCH_DETECT_PULLUP_CONF_REG, 0x10);
169 /* Auto mode init period = 5ms , scan period = 5ms*/
170 max11801_write_reg(client, AUTO_MODE_TIME_CONF_REG, 0xaa);
171 /* Aperture X,Y set to +- 4LSB */
172 max11801_write_reg(client, APERTURE_CONF_REG, 0x33);
173 /* Enable Power, enable Automode, enable Aperture, enable Average X,Y */
174 max11801_write_reg(client, OP_MODE_CONF_REG, 0x36);
175}
176
177static int __devinit max11801_ts_probe(struct i2c_client *client,
178 const struct i2c_device_id *id)
179{
180 struct max11801_data *data;
181 struct input_dev *input_dev;
182 int error;
183
184 data = kzalloc(sizeof(struct max11801_data), GFP_KERNEL);
185 input_dev = input_allocate_device();
186 if (!data || !input_dev) {
187 dev_err(&client->dev, "Failed to allocate memory\n");
188 error = -ENOMEM;
189 goto err_free_mem;
190 }
191
192 data->client = client;
193 data->input_dev = input_dev;
194
195 input_dev->name = "max11801_ts";
196 input_dev->id.bustype = BUS_I2C;
197 input_dev->dev.parent = &client->dev;
198
199 __set_bit(EV_ABS, input_dev->evbit);
200 __set_bit(EV_KEY, input_dev->evbit);
201 __set_bit(BTN_TOUCH, input_dev->keybit);
202 input_set_abs_params(input_dev, ABS_X, 0, MAX11801_MAX_X, 0, 0);
203 input_set_abs_params(input_dev, ABS_Y, 0, MAX11801_MAX_Y, 0, 0);
204 input_set_drvdata(input_dev, data);
205
206 max11801_ts_phy_init(data);
207
208 error = request_threaded_irq(client->irq, NULL, max11801_ts_interrupt,
209 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
210 "max11801_ts", data);
211 if (error) {
212 dev_err(&client->dev, "Failed to register interrupt\n");
213 goto err_free_mem;
214 }
215
216 error = input_register_device(data->input_dev);
217 if (error)
218 goto err_free_irq;
219
220 i2c_set_clientdata(client, data);
221 return 0;
222
223err_free_irq:
224 free_irq(client->irq, data);
225err_free_mem:
226 input_free_device(input_dev);
227 kfree(data);
228 return error;
229}
230
231static __devexit int max11801_ts_remove(struct i2c_client *client)
232{
233 struct max11801_data *data = i2c_get_clientdata(client);
234
235 free_irq(client->irq, data);
236 input_unregister_device(data->input_dev);
237 kfree(data);
238
239 return 0;
240}
241
242static const struct i2c_device_id max11801_ts_id[] = {
243 {"max11801", 0},
244 { }
245};
246MODULE_DEVICE_TABLE(i2c, max11801_ts_id);
247
248static struct i2c_driver max11801_ts_driver = {
249 .driver = {
250 .name = "max11801_ts",
251 .owner = THIS_MODULE,
252 },
253 .id_table = max11801_ts_id,
254 .probe = max11801_ts_probe,
255 .remove = __devexit_p(max11801_ts_remove),
256};
257
258static int __init max11801_ts_init(void)
259{
260 return i2c_add_driver(&max11801_ts_driver);
261}
262
263static void __exit max11801_ts_exit(void)
264{
265 i2c_del_driver(&max11801_ts_driver);
266}
267
268module_init(max11801_ts_init);
269module_exit(max11801_ts_exit);
270
271MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
272MODULE_DESCRIPTION("Touchscreen driver for MAXI MAX11801 controller");
273MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Driver for MAXI MAX11801 - A Resistive touch screen controller with
4 * i2c interface
5 *
6 * Copyright (C) 2011 Freescale Semiconductor, Inc.
7 * Author: Zhang Jiejing <jiejing.zhang@freescale.com>
8 *
9 * Based on mcs5000_ts.c
10 */
11
12/*
13 * This driver aims to support the series of MAXI touch chips max11801
14 * through max11803. The main difference between these 4 chips can be
15 * found in the table below:
16 * -----------------------------------------------------
17 * | CHIP | AUTO MODE SUPPORT(FIFO) | INTERFACE |
18 * |----------------------------------------------------|
19 * | max11800 | YES | SPI |
20 * | max11801 | YES | I2C |
21 * | max11802 | NO | SPI |
22 * | max11803 | NO | I2C |
23 * ------------------------------------------------------
24 *
25 * Currently, this driver only supports max11801.
26 *
27 * Data Sheet:
28 * http://www.maxim-ic.com/datasheet/index.mvp/id/5943
29 */
30
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/* Register Address define */
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 /* only for max11800/max11801 */
48#define APERTURE_CONF_REG 0x09 /* only for max11800/max11801 */
49#define AUX_MESURE_CONF_REG 0x0a
50#define OP_MODE_CONF_REG 0x0b
51
52/* FIFO is found only in max11800 and max11801 */
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/* These are the state of touch event state machine */
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 /* XXX: The chip ignores LSB of register address */
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 /* XXX: The chip ignores LSB of register address */
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 * We should get 4 bytes buffer that contains X,Y
114 * and event tag
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 case EVENT_MIDDLE:
134 input_report_abs(data->input_dev, ABS_X, x);
135 input_report_abs(data->input_dev, ABS_Y, y);
136 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 1);
137 input_sync(data->input_dev);
138 break;
139
140 case EVENT_RELEASE:
141 input_event(data->input_dev, EV_KEY, BTN_TOUCH, 0);
142 input_sync(data->input_dev);
143 break;
144
145 case EVENT_FIFO_END:
146 break;
147 }
148 }
149out:
150 return IRQ_HANDLED;
151}
152
153static void max11801_ts_phy_init(struct max11801_data *data)
154{
155 struct i2c_client *client = data->client;
156
157 /* Average X,Y, take 16 samples, average eight media sample */
158 max11801_write_reg(client, MESURE_AVER_CONF_REG, 0xff);
159 /* X,Y panel setup time set to 20us */
160 max11801_write_reg(client, PANEL_SETUPTIME_CONF_REG, 0x11);
161 /* Rough pullup time (2uS), Fine pullup time (10us) */
162 max11801_write_reg(client, TOUCH_DETECT_PULLUP_CONF_REG, 0x10);
163 /* Auto mode init period = 5ms , scan period = 5ms*/
164 max11801_write_reg(client, AUTO_MODE_TIME_CONF_REG, 0xaa);
165 /* Aperture X,Y set to +- 4LSB */
166 max11801_write_reg(client, APERTURE_CONF_REG, 0x33);
167 /* Enable Power, enable Automode, enable Aperture, enable Average X,Y */
168 max11801_write_reg(client, OP_MODE_CONF_REG, 0x36);
169}
170
171static int max11801_ts_probe(struct i2c_client *client)
172{
173 struct max11801_data *data;
174 struct input_dev *input_dev;
175 int error;
176
177 data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
178 input_dev = devm_input_allocate_device(&client->dev);
179 if (!data || !input_dev) {
180 dev_err(&client->dev, "Failed to allocate memory\n");
181 return -ENOMEM;
182 }
183
184 data->client = client;
185 data->input_dev = input_dev;
186
187 input_dev->name = "max11801_ts";
188 input_dev->id.bustype = BUS_I2C;
189 input_dev->dev.parent = &client->dev;
190
191 __set_bit(EV_ABS, input_dev->evbit);
192 __set_bit(EV_KEY, input_dev->evbit);
193 __set_bit(BTN_TOUCH, input_dev->keybit);
194 input_set_abs_params(input_dev, ABS_X, 0, MAX11801_MAX_X, 0, 0);
195 input_set_abs_params(input_dev, ABS_Y, 0, MAX11801_MAX_Y, 0, 0);
196
197 max11801_ts_phy_init(data);
198
199 error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
200 max11801_ts_interrupt,
201 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
202 "max11801_ts", data);
203 if (error) {
204 dev_err(&client->dev, "Failed to register interrupt\n");
205 return error;
206 }
207
208 error = input_register_device(data->input_dev);
209 if (error)
210 return error;
211
212 return 0;
213}
214
215static const struct i2c_device_id max11801_ts_id[] = {
216 {"max11801", 0},
217 { }
218};
219MODULE_DEVICE_TABLE(i2c, max11801_ts_id);
220
221static const struct of_device_id max11801_ts_dt_ids[] = {
222 { .compatible = "maxim,max11801" },
223 { /* sentinel */ }
224};
225MODULE_DEVICE_TABLE(of, max11801_ts_dt_ids);
226
227static struct i2c_driver max11801_ts_driver = {
228 .driver = {
229 .name = "max11801_ts",
230 .of_match_table = max11801_ts_dt_ids,
231 },
232 .id_table = max11801_ts_id,
233 .probe = max11801_ts_probe,
234};
235
236module_i2c_driver(max11801_ts_driver);
237
238MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
239MODULE_DESCRIPTION("Touchscreen driver for MAXI MAX11801 controller");
240MODULE_LICENSE("GPL");