243 lines
6.9 KiB
C
243 lines
6.9 KiB
C
/*
|
|
* Driver for MAXI MAX11801 - A Resistive touch screen controller with
|
|
* i2c interface
|
|
*
|
|
* Copyright (C) 2011 Freescale Semiconductor, Inc.
|
|
* Author: Zhang Jiejing <jiejing.zhang@freescale.com>
|
|
*
|
|
* Based on mcs5000_ts.c
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
/*
|
|
* This driver aims to support the series of MAXI touch chips max11801
|
|
* through max11803. The main difference between these 4 chips can be
|
|
* found in the table below:
|
|
* -----------------------------------------------------
|
|
* | CHIP | AUTO MODE SUPPORT(FIFO) | INTERFACE |
|
|
* |----------------------------------------------------|
|
|
* | max11800 | YES | SPI |
|
|
* | max11801 | YES | I2C |
|
|
* | max11802 | NO | SPI |
|
|
* | max11803 | NO | I2C |
|
|
* ------------------------------------------------------
|
|
*
|
|
* Currently, this driver only supports max11801.
|
|
*
|
|
* Data Sheet:
|
|
* http://www.maxim-ic.com/datasheet/index.mvp/id/5943
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/input.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/bitops.h>
|
|
|
|
/* Register Address define */
|
|
#define GENERNAL_STATUS_REG 0x00
|
|
#define GENERNAL_CONF_REG 0x01
|
|
#define MESURE_RES_CONF_REG 0x02
|
|
#define MESURE_AVER_CONF_REG 0x03
|
|
#define ADC_SAMPLE_TIME_CONF_REG 0x04
|
|
#define PANEL_SETUPTIME_CONF_REG 0x05
|
|
#define DELAY_CONVERSION_CONF_REG 0x06
|
|
#define TOUCH_DETECT_PULLUP_CONF_REG 0x07
|
|
#define AUTO_MODE_TIME_CONF_REG 0x08 /* only for max11800/max11801 */
|
|
#define APERTURE_CONF_REG 0x09 /* only for max11800/max11801 */
|
|
#define AUX_MESURE_CONF_REG 0x0a
|
|
#define OP_MODE_CONF_REG 0x0b
|
|
|
|
/* FIFO is found only in max11800 and max11801 */
|
|
#define FIFO_RD_CMD (0x50 << 1)
|
|
#define MAX11801_FIFO_INT (1 << 2)
|
|
#define MAX11801_FIFO_OVERFLOW (1 << 3)
|
|
|
|
#define XY_BUFSIZE 4
|
|
#define XY_BUF_OFFSET 4
|
|
|
|
#define MAX11801_MAX_X 0xfff
|
|
#define MAX11801_MAX_Y 0xfff
|
|
|
|
#define MEASURE_TAG_OFFSET 2
|
|
#define MEASURE_TAG_MASK (3 << MEASURE_TAG_OFFSET)
|
|
#define EVENT_TAG_OFFSET 0
|
|
#define EVENT_TAG_MASK (3 << EVENT_TAG_OFFSET)
|
|
#define MEASURE_X_TAG (0 << MEASURE_TAG_OFFSET)
|
|
#define MEASURE_Y_TAG (1 << MEASURE_TAG_OFFSET)
|
|
|
|
/* These are the state of touch event state machine */
|
|
enum {
|
|
EVENT_INIT,
|
|
EVENT_MIDDLE,
|
|
EVENT_RELEASE,
|
|
EVENT_FIFO_END
|
|
};
|
|
|
|
struct max11801_data {
|
|
struct i2c_client *client;
|
|
struct input_dev *input_dev;
|
|
};
|
|
|
|
static u8 read_register(struct i2c_client *client, int addr)
|
|
{
|
|
/* XXX: The chip ignores LSB of register address */
|
|
return i2c_smbus_read_byte_data(client, addr << 1);
|
|
}
|
|
|
|
static int max11801_write_reg(struct i2c_client *client, int addr, int data)
|
|
{
|
|
/* XXX: The chip ignores LSB of register address */
|
|
return i2c_smbus_write_byte_data(client, addr << 1, data);
|
|
}
|
|
|
|
static irqreturn_t max11801_ts_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct max11801_data *data = dev_id;
|
|
struct i2c_client *client = data->client;
|
|
int status, i, ret;
|
|
u8 buf[XY_BUFSIZE];
|
|
int x = -1;
|
|
int y = -1;
|
|
|
|
status = read_register(data->client, GENERNAL_STATUS_REG);
|
|
|
|
if (status & (MAX11801_FIFO_INT | MAX11801_FIFO_OVERFLOW)) {
|
|
status = read_register(data->client, GENERNAL_STATUS_REG);
|
|
|
|
ret = i2c_smbus_read_i2c_block_data(client, FIFO_RD_CMD,
|
|
XY_BUFSIZE, buf);
|
|
|
|
/*
|
|
* We should get 4 bytes buffer that contains X,Y
|
|
* and event tag
|
|
*/
|
|
if (ret < XY_BUFSIZE)
|
|
goto out;
|
|
|
|
for (i = 0; i < XY_BUFSIZE; i += XY_BUFSIZE / 2) {
|
|
if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_X_TAG)
|
|
x = (buf[i] << XY_BUF_OFFSET) +
|
|
(buf[i + 1] >> XY_BUF_OFFSET);
|
|
else if ((buf[i + 1] & MEASURE_TAG_MASK) == MEASURE_Y_TAG)
|
|
y = (buf[i] << XY_BUF_OFFSET) +
|
|
(buf[i + 1] >> XY_BUF_OFFSET);
|
|
}
|
|
|
|
if ((buf[1] & EVENT_TAG_MASK) != (buf[3] & EVENT_TAG_MASK))
|
|
goto out;
|
|
|
|
switch (buf[1] & EVENT_TAG_MASK) {
|
|
case EVENT_INIT:
|
|
/* fall through */
|
|
case EVENT_MIDDLE:
|
|
input_report_abs(data->input_dev, ABS_X, x);
|
|
input_report_abs(data->input_dev, ABS_Y, y);
|
|
input_event(data->input_dev, EV_KEY, BTN_TOUCH, 1);
|
|
input_sync(data->input_dev);
|
|
break;
|
|
|
|
case EVENT_RELEASE:
|
|
input_event(data->input_dev, EV_KEY, BTN_TOUCH, 0);
|
|
input_sync(data->input_dev);
|
|
break;
|
|
|
|
case EVENT_FIFO_END:
|
|
break;
|
|
}
|
|
}
|
|
out:
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static void max11801_ts_phy_init(struct max11801_data *data)
|
|
{
|
|
struct i2c_client *client = data->client;
|
|
|
|
/* Average X,Y, take 16 samples, average eight media sample */
|
|
max11801_write_reg(client, MESURE_AVER_CONF_REG, 0xff);
|
|
/* X,Y panel setup time set to 20us */
|
|
max11801_write_reg(client, PANEL_SETUPTIME_CONF_REG, 0x11);
|
|
/* Rough pullup time (2uS), Fine pullup time (10us) */
|
|
max11801_write_reg(client, TOUCH_DETECT_PULLUP_CONF_REG, 0x10);
|
|
/* Auto mode init period = 5ms , scan period = 5ms*/
|
|
max11801_write_reg(client, AUTO_MODE_TIME_CONF_REG, 0xaa);
|
|
/* Aperture X,Y set to +- 4LSB */
|
|
max11801_write_reg(client, APERTURE_CONF_REG, 0x33);
|
|
/* Enable Power, enable Automode, enable Aperture, enable Average X,Y */
|
|
max11801_write_reg(client, OP_MODE_CONF_REG, 0x36);
|
|
}
|
|
|
|
static int max11801_ts_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct max11801_data *data;
|
|
struct input_dev *input_dev;
|
|
int error;
|
|
|
|
data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
|
|
input_dev = devm_input_allocate_device(&client->dev);
|
|
if (!data || !input_dev) {
|
|
dev_err(&client->dev, "Failed to allocate memory\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
data->client = client;
|
|
data->input_dev = input_dev;
|
|
|
|
input_dev->name = "max11801_ts";
|
|
input_dev->id.bustype = BUS_I2C;
|
|
input_dev->dev.parent = &client->dev;
|
|
|
|
__set_bit(EV_ABS, input_dev->evbit);
|
|
__set_bit(EV_KEY, input_dev->evbit);
|
|
__set_bit(BTN_TOUCH, input_dev->keybit);
|
|
input_set_abs_params(input_dev, ABS_X, 0, MAX11801_MAX_X, 0, 0);
|
|
input_set_abs_params(input_dev, ABS_Y, 0, MAX11801_MAX_Y, 0, 0);
|
|
input_set_drvdata(input_dev, data);
|
|
|
|
max11801_ts_phy_init(data);
|
|
|
|
error = devm_request_threaded_irq(&client->dev, client->irq, NULL,
|
|
max11801_ts_interrupt,
|
|
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
|
|
"max11801_ts", data);
|
|
if (error) {
|
|
dev_err(&client->dev, "Failed to register interrupt\n");
|
|
return error;
|
|
}
|
|
|
|
error = input_register_device(data->input_dev);
|
|
if (error)
|
|
return error;
|
|
|
|
i2c_set_clientdata(client, data);
|
|
return 0;
|
|
}
|
|
|
|
static const struct i2c_device_id max11801_ts_id[] = {
|
|
{"max11801", 0},
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, max11801_ts_id);
|
|
|
|
static struct i2c_driver max11801_ts_driver = {
|
|
.driver = {
|
|
.name = "max11801_ts",
|
|
.owner = THIS_MODULE,
|
|
},
|
|
.id_table = max11801_ts_id,
|
|
.probe = max11801_ts_probe,
|
|
};
|
|
|
|
module_i2c_driver(max11801_ts_driver);
|
|
|
|
MODULE_AUTHOR("Zhang Jiejing <jiejing.zhang@freescale.com>");
|
|
MODULE_DESCRIPTION("Touchscreen driver for MAXI MAX11801 controller");
|
|
MODULE_LICENSE("GPL");
|