blob: e38ba3e4f1837793c2d6d0c8dd6729011d08fcf9 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* ST1232 Touchscreen Controller Driver
*
* Copyright (C) 2010 Renesas Solutions Corp.
* Tony SIM <chinyeow.sim.xt@renesas.com>
*
* Using code from:
* - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
* Copyright (C) 2007 Google, Inc.
*/
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pm_qos.h>
#include <linux/slab.h>
#include <linux/types.h>
#define ST1232_TS_NAME "st1232-ts"
#define ST1633_TS_NAME "st1633-ts"
#define REG_STATUS 0x01 /* Device Status | Error Code */
#define STATUS_NORMAL 0x00
#define STATUS_INIT 0x01
#define STATUS_ERROR 0x02
#define STATUS_AUTO_TUNING 0x03
#define STATUS_IDLE 0x04
#define STATUS_POWER_DOWN 0x05
#define ERROR_NONE 0x00
#define ERROR_INVALID_ADDRESS 0x10
#define ERROR_INVALID_VALUE 0x20
#define ERROR_INVALID_PLATFORM 0x30
#define REG_XY_RESOLUTION 0x04
#define REG_XY_COORDINATES 0x12
#define ST_TS_MAX_FINGERS 10
struct st_chip_info {
bool have_z;
u16 max_area;
u16 max_fingers;
};
struct st1232_ts_data {
struct i2c_client *client;
struct input_dev *input_dev;
struct touchscreen_properties prop;
struct dev_pm_qos_request low_latency_req;
struct gpio_desc *reset_gpio;
const struct st_chip_info *chip_info;
int read_buf_len;
u8 *read_buf;
};
static int st1232_ts_read_data(struct st1232_ts_data *ts, u8 reg,
unsigned int n)
{
struct i2c_client *client = ts->client;
struct i2c_msg msg[] = {
{
.addr = client->addr,
.len = sizeof(reg),
.buf = &reg,
},
{
.addr = client->addr,
.flags = I2C_M_RD | I2C_M_DMA_SAFE,
.len = n,
.buf = ts->read_buf,
}
};
int ret;
ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (ret != ARRAY_SIZE(msg))
return ret < 0 ? ret : -EIO;
return 0;
}
static int st1232_ts_wait_ready(struct st1232_ts_data *ts)
{
unsigned int retries;
int error;
for (retries = 100; retries; retries--) {
error = st1232_ts_read_data(ts, REG_STATUS, 1);
if (!error) {
switch (ts->read_buf[0]) {
case STATUS_NORMAL | ERROR_NONE:
case STATUS_IDLE | ERROR_NONE:
return 0;
}
}
usleep_range(1000, 2000);
}
return -ENXIO;
}
static int st1232_ts_read_resolution(struct st1232_ts_data *ts, u16 *max_x,
u16 *max_y)
{
u8 *buf;
int error;
/* select resolution register */
error = st1232_ts_read_data(ts, REG_XY_RESOLUTION, 3);
if (error)
return error;
buf = ts->read_buf;
*max_x = (((buf[0] & 0x0070) << 4) | buf[1]) - 1;
*max_y = (((buf[0] & 0x0007) << 8) | buf[2]) - 1;
return 0;
}
static int st1232_ts_parse_and_report(struct st1232_ts_data *ts)
{
struct input_dev *input = ts->input_dev;
struct input_mt_pos pos[ST_TS_MAX_FINGERS];
u8 z[ST_TS_MAX_FINGERS];
int slots[ST_TS_MAX_FINGERS];
int n_contacts = 0;
int i;
for (i = 0; i < ts->chip_info->max_fingers; i++) {
u8 *buf = &ts->read_buf[i * 4];
if (buf[0] & BIT(7)) {
unsigned int x = ((buf[0] & 0x70) << 4) | buf[1];
unsigned int y = ((buf[0] & 0x07) << 8) | buf[2];
touchscreen_set_mt_pos(&pos[n_contacts],
&ts->prop, x, y);
/* st1232 includes a z-axis / touch strength */
if (ts->chip_info->have_z)
z[n_contacts] = ts->read_buf[i + 6];
n_contacts++;
}
}
input_mt_assign_slots(input, slots, pos, n_contacts, 0);
for (i = 0; i < n_contacts; i++) {
input_mt_slot(input, slots[i]);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
if (ts->chip_info->have_z)
input_report_abs(input, ABS_MT_TOUCH_MAJOR, z[i]);
}
input_mt_sync_frame(input);
input_sync(input);
return n_contacts;
}
static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
{
struct st1232_ts_data *ts = dev_id;
int count;
int error;
error = st1232_ts_read_data(ts, REG_XY_COORDINATES, ts->read_buf_len);
if (error)
goto out;
count = st1232_ts_parse_and_report(ts);
if (!count) {
if (ts->low_latency_req.dev) {
dev_pm_qos_remove_request(&ts->low_latency_req);
ts->low_latency_req.dev = NULL;
}
} else if (!ts->low_latency_req.dev) {
/* First contact, request 100 us latency. */
dev_pm_qos_add_ancestor_request(&ts->client->dev,
&ts->low_latency_req,
DEV_PM_QOS_RESUME_LATENCY, 100);
}
out:
return IRQ_HANDLED;
}
static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron)
{
if (ts->reset_gpio)
gpiod_set_value_cansleep(ts->reset_gpio, !poweron);
}
static void st1232_ts_power_off(void *data)
{
st1232_ts_power(data, false);
}
static const struct st_chip_info st1232_chip_info = {
.have_z = true,
.max_area = 0xff,
.max_fingers = 2,
};
static const struct st_chip_info st1633_chip_info = {
.have_z = false,
.max_area = 0x00,
.max_fingers = 5,
};
static int st1232_ts_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const struct st_chip_info *match;
struct st1232_ts_data *ts;
struct input_dev *input_dev;
u16 max_x, max_y;
int error;
match = device_get_match_data(&client->dev);
if (!match && id)
match = (const void *)id->driver_data;
if (!match) {
dev_err(&client->dev, "unknown device model\n");
return -ENODEV;
}
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "need I2C_FUNC_I2C\n");
return -EIO;
}
if (!client->irq) {
dev_err(&client->dev, "no IRQ?\n");
return -EINVAL;
}
ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
if (!ts)
return -ENOMEM;
ts->chip_info = match;
/* allocate a buffer according to the number of registers to read */
ts->read_buf_len = ts->chip_info->max_fingers * 4;
ts->read_buf = devm_kzalloc(&client->dev, ts->read_buf_len, GFP_KERNEL);
if (!ts->read_buf)
return -ENOMEM;
input_dev = devm_input_allocate_device(&client->dev);
if (!input_dev)
return -ENOMEM;
ts->client = client;
ts->input_dev = input_dev;
ts->reset_gpio = devm_gpiod_get_optional(&client->dev, NULL,
GPIOD_OUT_HIGH);
if (IS_ERR(ts->reset_gpio)) {
error = PTR_ERR(ts->reset_gpio);
dev_err(&client->dev, "Unable to request GPIO pin: %d.\n",
error);
return error;
}
st1232_ts_power(ts, true);
error = devm_add_action_or_reset(&client->dev, st1232_ts_power_off, ts);
if (error) {
dev_err(&client->dev,
"Failed to install power off action: %d\n", error);
return error;
}
input_dev->name = "st1232-touchscreen";
input_dev->id.bustype = BUS_I2C;
/* Wait until device is ready */
error = st1232_ts_wait_ready(ts);
if (error)
return error;
/* Read resolution from the chip */
error = st1232_ts_read_resolution(ts, &max_x, &max_y);
if (error) {
dev_err(&client->dev,
"Failed to read resolution: %d\n", error);
return error;
}
if (ts->chip_info->have_z)
input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0,
ts->chip_info->max_area, 0, 0);
input_set_abs_params(input_dev, ABS_MT_POSITION_X,
0, max_x, 0, 0);
input_set_abs_params(input_dev, ABS_MT_POSITION_Y,
0, max_y, 0, 0);
touchscreen_parse_properties(input_dev, true, &ts->prop);
error = input_mt_init_slots(input_dev, ts->chip_info->max_fingers,
INPUT_MT_DIRECT | INPUT_MT_TRACK |
INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(&client->dev, "failed to initialize MT slots\n");
return error;
}
error = devm_request_threaded_irq(&client->dev, client->irq,
NULL, st1232_ts_irq_handler,
IRQF_ONESHOT,
client->name, ts);
if (error) {
dev_err(&client->dev, "Failed to register interrupt\n");
return error;
}
error = input_register_device(ts->input_dev);
if (error) {
dev_err(&client->dev, "Unable to register %s input device\n",
input_dev->name);
return error;
}
i2c_set_clientdata(client, ts);
return 0;
}
static int __maybe_unused st1232_ts_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct st1232_ts_data *ts = i2c_get_clientdata(client);
disable_irq(client->irq);
if (!device_may_wakeup(&client->dev))
st1232_ts_power(ts, false);
return 0;
}
static int __maybe_unused st1232_ts_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct st1232_ts_data *ts = i2c_get_clientdata(client);
if (!device_may_wakeup(&client->dev))
st1232_ts_power(ts, true);
enable_irq(client->irq);
return 0;
}
static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
st1232_ts_suspend, st1232_ts_resume);
static const struct i2c_device_id st1232_ts_id[] = {
{ ST1232_TS_NAME, (unsigned long)&st1232_chip_info },
{ ST1633_TS_NAME, (unsigned long)&st1633_chip_info },
{ }
};
MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
static const struct of_device_id st1232_ts_dt_ids[] = {
{ .compatible = "sitronix,st1232", .data = &st1232_chip_info },
{ .compatible = "sitronix,st1633", .data = &st1633_chip_info },
{ }
};
MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
static struct i2c_driver st1232_ts_driver = {
.probe = st1232_ts_probe,
.id_table = st1232_ts_id,
.driver = {
.name = ST1232_TS_NAME,
.of_match_table = st1232_ts_dt_ids,
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.pm = &st1232_ts_pm_ops,
},
};
module_i2c_driver(st1232_ts_driver);
MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
MODULE_AUTHOR("Martin Kepplinger <martin.kepplinger@ginzinger.com>");
MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
MODULE_LICENSE("GPL v2");