linux-zen-desktop/drivers/input/touchscreen/msg2638.c

507 lines
12 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Driver for MStar msg2638 touchscreens
*
* Copyright (c) 2021 Vincent Knecht <vincent.knecht@mailoo.org>
*
* Checksum and IRQ handler based on mstar_drv_common.c and
* mstar_drv_mutual_fw_control.c
* Copyright (c) 2006-2012 MStar Semiconductor, Inc.
*
* Driver structure based on zinitix.c by Michael Srba <Michael.Srba@seznam.cz>
*/
#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/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#define MODE_DATA_RAW 0x5A
#define MSG2138_MAX_FINGERS 2
#define MSG2638_MAX_FINGERS 5
#define MAX_BUTTONS 4
#define CHIP_ON_DELAY_MS 15
#define FIRMWARE_ON_DELAY_MS 50
#define RESET_DELAY_MIN_US 10000
#define RESET_DELAY_MAX_US 11000
struct msg_chip_data {
irq_handler_t irq_handler;
unsigned int max_fingers;
};
struct msg2138_packet {
u8 xy_hi; /* higher bits of x and y coordinates */
u8 x_low;
u8 y_low;
};
struct msg2138_touch_event {
u8 magic;
struct msg2138_packet pkt[MSG2138_MAX_FINGERS];
u8 checksum;
};
struct msg2638_packet {
u8 xy_hi; /* higher bits of x and y coordinates */
u8 x_low;
u8 y_low;
u8 pressure;
};
struct msg2638_touch_event {
u8 mode;
struct msg2638_packet pkt[MSG2638_MAX_FINGERS];
u8 proximity;
u8 checksum;
};
struct msg2638_ts_data {
struct i2c_client *client;
struct input_dev *input_dev;
struct touchscreen_properties prop;
struct regulator_bulk_data supplies[2];
struct gpio_desc *reset_gpiod;
int max_fingers;
u32 keycodes[MAX_BUTTONS];
int num_keycodes;
};
static u8 msg2638_checksum(u8 *data, u32 length)
{
s32 sum = 0;
u32 i;
for (i = 0; i < length; i++)
sum += data[i];
return (u8)((-sum) & 0xFF);
}
static void msg2138_report_keys(struct msg2638_ts_data *msg2638, u8 keys)
{
int i;
/* keys can be 0x00 or 0xff when all keys have been released */
if (keys == 0xff)
keys = 0;
for (i = 0; i < msg2638->num_keycodes; ++i)
input_report_key(msg2638->input_dev, msg2638->keycodes[i],
keys & BIT(i));
}
static irqreturn_t msg2138_ts_irq_handler(int irq, void *msg2638_handler)
{
struct msg2638_ts_data *msg2638 = msg2638_handler;
struct i2c_client *client = msg2638->client;
struct input_dev *input = msg2638->input_dev;
struct msg2138_touch_event touch_event;
u32 len = sizeof(touch_event);
struct i2c_msg msg[] = {
{
.addr = client->addr,
.flags = I2C_M_RD,
.len = sizeof(touch_event),
.buf = (u8 *)&touch_event,
},
};
struct msg2138_packet *p0, *p1;
u16 x, y, delta_x, delta_y;
int ret;
ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (ret != ARRAY_SIZE(msg)) {
dev_err(&client->dev,
"Failed I2C transfer in irq handler: %d\n",
ret < 0 ? ret : -EIO);
goto out;
}
if (msg2638_checksum((u8 *)&touch_event, len - 1) !=
touch_event.checksum) {
dev_err(&client->dev, "Failed checksum!\n");
goto out;
}
p0 = &touch_event.pkt[0];
p1 = &touch_event.pkt[1];
/* Ignore non-pressed finger data, but check for key code */
if (p0->xy_hi == 0xFF && p0->x_low == 0xFF && p0->y_low == 0xFF) {
if (p1->xy_hi == 0xFF && p1->y_low == 0xFF)
msg2138_report_keys(msg2638, p1->x_low);
goto report;
}
x = ((p0->xy_hi & 0xF0) << 4) | p0->x_low;
y = ((p0->xy_hi & 0x0F) << 8) | p0->y_low;
input_mt_slot(input, 0);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
touchscreen_report_pos(input, &msg2638->prop, x, y, true);
/* Ignore non-pressed finger data */
if (p1->xy_hi == 0xFF && p1->x_low == 0xFF && p1->y_low == 0xFF)
goto report;
/* Second finger is reported as a delta position */
delta_x = ((p1->xy_hi & 0xF0) << 4) | p1->x_low;
delta_y = ((p1->xy_hi & 0x0F) << 8) | p1->y_low;
/* Ignore second finger if both deltas equal 0 */
if (delta_x == 0 && delta_y == 0)
goto report;
x += delta_x;
y += delta_y;
input_mt_slot(input, 1);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
touchscreen_report_pos(input, &msg2638->prop, x, y, true);
report:
input_mt_sync_frame(msg2638->input_dev);
input_sync(msg2638->input_dev);
out:
return IRQ_HANDLED;
}
static irqreturn_t msg2638_ts_irq_handler(int irq, void *msg2638_handler)
{
struct msg2638_ts_data *msg2638 = msg2638_handler;
struct i2c_client *client = msg2638->client;
struct input_dev *input = msg2638->input_dev;
struct msg2638_touch_event touch_event;
u32 len = sizeof(touch_event);
struct i2c_msg msg[] = {
{
.addr = client->addr,
.flags = I2C_M_RD,
.len = sizeof(touch_event),
.buf = (u8 *)&touch_event,
},
};
struct msg2638_packet *p;
u16 x, y;
int ret;
int i;
ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
if (ret != ARRAY_SIZE(msg)) {
dev_err(&client->dev,
"Failed I2C transfer in irq handler: %d\n",
ret < 0 ? ret : -EIO);
goto out;
}
if (touch_event.mode != MODE_DATA_RAW)
goto out;
if (msg2638_checksum((u8 *)&touch_event, len - 1) !=
touch_event.checksum) {
dev_err(&client->dev, "Failed checksum!\n");
goto out;
}
for (i = 0; i < msg2638->max_fingers; i++) {
p = &touch_event.pkt[i];
/* Ignore non-pressed finger data */
if (p->xy_hi == 0xFF && p->x_low == 0xFF && p->y_low == 0xFF)
continue;
x = (((p->xy_hi & 0xF0) << 4) | p->x_low);
y = (((p->xy_hi & 0x0F) << 8) | p->y_low);
input_mt_slot(input, i);
input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
touchscreen_report_pos(input, &msg2638->prop, x, y, true);
}
input_mt_sync_frame(msg2638->input_dev);
input_sync(msg2638->input_dev);
out:
return IRQ_HANDLED;
}
static void msg2638_reset(struct msg2638_ts_data *msg2638)
{
gpiod_set_value_cansleep(msg2638->reset_gpiod, 1);
usleep_range(RESET_DELAY_MIN_US, RESET_DELAY_MAX_US);
gpiod_set_value_cansleep(msg2638->reset_gpiod, 0);
msleep(FIRMWARE_ON_DELAY_MS);
}
static int msg2638_start(struct msg2638_ts_data *msg2638)
{
int error;
error = regulator_bulk_enable(ARRAY_SIZE(msg2638->supplies),
msg2638->supplies);
if (error) {
dev_err(&msg2638->client->dev,
"Failed to enable regulators: %d\n", error);
return error;
}
msleep(CHIP_ON_DELAY_MS);
msg2638_reset(msg2638);
enable_irq(msg2638->client->irq);
return 0;
}
static int msg2638_stop(struct msg2638_ts_data *msg2638)
{
int error;
disable_irq(msg2638->client->irq);
error = regulator_bulk_disable(ARRAY_SIZE(msg2638->supplies),
msg2638->supplies);
if (error) {
dev_err(&msg2638->client->dev,
"Failed to disable regulators: %d\n", error);
return error;
}
return 0;
}
static int msg2638_input_open(struct input_dev *dev)
{
struct msg2638_ts_data *msg2638 = input_get_drvdata(dev);
return msg2638_start(msg2638);
}
static void msg2638_input_close(struct input_dev *dev)
{
struct msg2638_ts_data *msg2638 = input_get_drvdata(dev);
msg2638_stop(msg2638);
}
static int msg2638_init_input_dev(struct msg2638_ts_data *msg2638)
{
struct device *dev = &msg2638->client->dev;
struct input_dev *input_dev;
int error;
int i;
input_dev = devm_input_allocate_device(dev);
if (!input_dev) {
dev_err(dev, "Failed to allocate input device.\n");
return -ENOMEM;
}
input_set_drvdata(input_dev, msg2638);
msg2638->input_dev = input_dev;
input_dev->name = "MStar TouchScreen";
input_dev->phys = "input/ts";
input_dev->id.bustype = BUS_I2C;
input_dev->open = msg2638_input_open;
input_dev->close = msg2638_input_close;
if (msg2638->num_keycodes) {
input_dev->keycode = msg2638->keycodes;
input_dev->keycodemax = msg2638->num_keycodes;
input_dev->keycodesize = sizeof(msg2638->keycodes[0]);
for (i = 0; i < msg2638->num_keycodes; i++)
input_set_capability(input_dev,
EV_KEY, msg2638->keycodes[i]);
}
input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_X);
input_set_capability(input_dev, EV_ABS, ABS_MT_POSITION_Y);
touchscreen_parse_properties(input_dev, true, &msg2638->prop);
if (!msg2638->prop.max_x || !msg2638->prop.max_y) {
dev_err(dev, "touchscreen-size-x and/or touchscreen-size-y not set in properties\n");
return -EINVAL;
}
error = input_mt_init_slots(input_dev, msg2638->max_fingers,
INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
if (error) {
dev_err(dev, "Failed to initialize MT slots: %d\n", error);
return error;
}
error = input_register_device(input_dev);
if (error) {
dev_err(dev, "Failed to register input device: %d\n", error);
return error;
}
return 0;
}
static int msg2638_ts_probe(struct i2c_client *client)
{
const struct msg_chip_data *chip_data;
struct device *dev = &client->dev;
struct msg2638_ts_data *msg2638;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(dev, "Failed to assert adapter's support for plain I2C.\n");
return -ENXIO;
}
msg2638 = devm_kzalloc(dev, sizeof(*msg2638), GFP_KERNEL);
if (!msg2638)
return -ENOMEM;
msg2638->client = client;
i2c_set_clientdata(client, msg2638);
chip_data = device_get_match_data(&client->dev);
if (!chip_data || !chip_data->max_fingers) {
dev_err(dev, "Invalid or missing chip data\n");
return -EINVAL;
}
msg2638->max_fingers = chip_data->max_fingers;
msg2638->supplies[0].supply = "vdd";
msg2638->supplies[1].supply = "vddio";
error = devm_regulator_bulk_get(dev, ARRAY_SIZE(msg2638->supplies),
msg2638->supplies);
if (error) {
dev_err(dev, "Failed to get regulators: %d\n", error);
return error;
}
msg2638->reset_gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
if (IS_ERR(msg2638->reset_gpiod)) {
error = PTR_ERR(msg2638->reset_gpiod);
dev_err(dev, "Failed to request reset GPIO: %d\n", error);
return error;
}
msg2638->num_keycodes = device_property_count_u32(dev,
"linux,keycodes");
if (msg2638->num_keycodes == -EINVAL) {
msg2638->num_keycodes = 0;
} else if (msg2638->num_keycodes < 0) {
dev_err(dev, "Unable to parse linux,keycodes property: %d\n",
msg2638->num_keycodes);
return msg2638->num_keycodes;
} else if (msg2638->num_keycodes > ARRAY_SIZE(msg2638->keycodes)) {
dev_warn(dev, "Found %d linux,keycodes but max is %zd, ignoring the rest\n",
msg2638->num_keycodes, ARRAY_SIZE(msg2638->keycodes));
msg2638->num_keycodes = ARRAY_SIZE(msg2638->keycodes);
}
if (msg2638->num_keycodes > 0) {
error = device_property_read_u32_array(dev, "linux,keycodes",
msg2638->keycodes,
msg2638->num_keycodes);
if (error) {
dev_err(dev, "Unable to read linux,keycodes values: %d\n",
error);
return error;
}
}
error = devm_request_threaded_irq(dev, client->irq,
NULL, chip_data->irq_handler,
IRQF_ONESHOT | IRQF_NO_AUTOEN,
client->name, msg2638);
if (error) {
dev_err(dev, "Failed to request IRQ: %d\n", error);
return error;
}
error = msg2638_init_input_dev(msg2638);
if (error) {
dev_err(dev, "Failed to initialize input device: %d\n", error);
return error;
}
return 0;
}
static int msg2638_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct msg2638_ts_data *msg2638 = i2c_get_clientdata(client);
mutex_lock(&msg2638->input_dev->mutex);
if (input_device_enabled(msg2638->input_dev))
msg2638_stop(msg2638);
mutex_unlock(&msg2638->input_dev->mutex);
return 0;
}
static int msg2638_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct msg2638_ts_data *msg2638 = i2c_get_clientdata(client);
int ret = 0;
mutex_lock(&msg2638->input_dev->mutex);
if (input_device_enabled(msg2638->input_dev))
ret = msg2638_start(msg2638);
mutex_unlock(&msg2638->input_dev->mutex);
return ret;
}
static DEFINE_SIMPLE_DEV_PM_OPS(msg2638_pm_ops, msg2638_suspend, msg2638_resume);
static const struct msg_chip_data msg2138_data = {
.irq_handler = msg2138_ts_irq_handler,
.max_fingers = MSG2138_MAX_FINGERS,
};
static const struct msg_chip_data msg2638_data = {
.irq_handler = msg2638_ts_irq_handler,
.max_fingers = MSG2638_MAX_FINGERS,
};
static const struct of_device_id msg2638_of_match[] = {
{ .compatible = "mstar,msg2138", .data = &msg2138_data },
{ .compatible = "mstar,msg2638", .data = &msg2638_data },
{ }
};
MODULE_DEVICE_TABLE(of, msg2638_of_match);
static struct i2c_driver msg2638_ts_driver = {
.probe = msg2638_ts_probe,
.driver = {
.name = "MStar-TS",
.pm = pm_sleep_ptr(&msg2638_pm_ops),
.of_match_table = msg2638_of_match,
},
};
module_i2c_driver(msg2638_ts_driver);
MODULE_AUTHOR("Vincent Knecht <vincent.knecht@mailoo.org>");
MODULE_DESCRIPTION("MStar MSG2638 touchscreen driver");
MODULE_LICENSE("GPL v2");