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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/i2c.h>
37#include <linux/interrupt.h>
38#include <linux/input.h>
39#include <linux/slab.h>
40#include <linux/bitops.h>
41
42/* Register Address define */
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 /* only for max11800/max11801 */
52#define APERTURE_CONF_REG 0x09 /* only for max11800/max11801 */
53#define AUX_MESURE_CONF_REG 0x0a
54#define OP_MODE_CONF_REG 0x0b
55
56/* FIFO is found only in max11800 and max11801 */
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/* These are the state of touch event state machine */
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 /* XXX: The chip ignores LSB of register address */
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 /* XXX: The chip ignores LSB of register address */
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 * We should get 4 bytes buffer that contains X,Y
118 * and event tag
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 /* fall through */
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 /* Average X,Y, take 16 samples, average eight media sample */
163 max11801_write_reg(client, MESURE_AVER_CONF_REG, 0xff);
164 /* X,Y panel setup time set to 20us */
165 max11801_write_reg(client, PANEL_SETUPTIME_CONF_REG, 0x11);
166 /* Rough pullup time (2uS), Fine pullup time (10us) */
167 max11801_write_reg(client, TOUCH_DETECT_PULLUP_CONF_REG, 0x10);
168 /* Auto mode init period = 5ms , scan period = 5ms*/
169 max11801_write_reg(client, AUTO_MODE_TIME_CONF_REG, 0xaa);
170 /* Aperture X,Y set to +- 4LSB */
171 max11801_write_reg(client, APERTURE_CONF_REG, 0x33);
172 /* Enable Power, enable Automode, enable Aperture, enable Average X,Y */
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 .owner = THIS_MODULE,
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");
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");