// SPDX-License-Identifier: GPL-2.0
// Samsung S6SY761 Touchscreen device driver
//
// Copyright (c) 2017 Samsung Electronics Co., Ltd.
// Copyright (c) 2017 Andi Shyti <[email protected]>
#include <linux/unaligned.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/input/mt.h>
#include <linux/input/touchscreen.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
/* commands */
#define S6SY761_SENSE_ON 0x10
#define S6SY761_SENSE_OFF 0x11
#define S6SY761_TOUCH_FUNCTION 0x30 /* R/W for get/set */
#define S6SY761_FIRMWARE_INTEGRITY 0x21
#define S6SY761_PANEL_INFO 0x23
#define S6SY761_DEVICE_ID 0x52
#define S6SY761_BOOT_STATUS 0x55
#define S6SY761_READ_ONE_EVENT 0x60
#define S6SY761_READ_ALL_EVENT 0x61
#define S6SY761_CLEAR_EVENT_STACK 0x62
#define S6SY761_APPLICATION_MODE 0xe4
/* events */
#define S6SY761_EVENT_INFO 0x02
#define S6SY761_EVENT_VENDOR_INFO 0x07
/* info */
#define S6SY761_INFO_BOOT_COMPLETE 0x00
/* firmware status */
#define S6SY761_FW_OK 0x80
/*
* the functionalities are put as a reference
* as in the device I am using none of them
* works therefore not used in this driver yet.
*/
/* touchscreen functionalities */
#define S6SY761_MASK_TOUCH BIT(0)
#define S6SY761_MASK_HOVER BIT(1)
#define S6SY761_MASK_COVER BIT(2)
#define S6SY761_MASK_GLOVE BIT(3)
#define S6SY761_MASK_STYLUS BIT(4)
#define S6SY761_MASK_PALM BIT(5)
#define S6SY761_MASK_WET BIT(6)
#define S6SY761_MASK_PROXIMITY BIT(7)
/* boot status (BS) */
#define S6SY761_BS_BOOT_LOADER 0x10
#define S6SY761_BS_APPLICATION 0x20
/* event id */
#define S6SY761_EVENT_ID_COORDINATE 0x00
#define S6SY761_EVENT_ID_STATUS 0x01
/* event register masks */
#define S6SY761_MASK_TOUCH_STATE 0xc0 /* byte 0 */
#define S6SY761_MASK_TID 0x3c
#define S6SY761_MASK_EID 0x03
#define S6SY761_MASK_X 0xf0 /* byte 3 */
#define S6SY761_MASK_Y 0x0f
#define S6SY761_MASK_Z 0x3f /* byte 6 */
#define S6SY761_MASK_LEFT_EVENTS 0x3f /* byte 7 */
#define S6SY761_MASK_TOUCH_TYPE 0xc0 /* MSB in byte 6, LSB in byte 7 */
/* event touch state values */
#define S6SY761_TS_NONE 0x00
#define S6SY761_TS_PRESS 0x01
#define S6SY761_TS_MOVE 0x02
#define S6SY761_TS_RELEASE 0x03
/* application modes */
#define S6SY761_APP_NORMAL 0x0
#define S6SY761_APP_LOW_POWER 0x1
#define S6SY761_APP_TEST 0x2
#define S6SY761_APP_FLASH 0x3
#define S6SY761_APP_SLEEP 0x4
#define S6SY761_EVENT_SIZE 8
#define S6SY761_EVENT_COUNT 32
#define S6SY761_DEVID_SIZE 3
#define S6SY761_PANEL_ID_SIZE 11
#define S6SY761_TS_STATUS_SIZE 5
#define S6SY761_MAX_FINGERS 10
#define S6SY761_DEV_NAME "s6sy761"
enum s6sy761_regulators {
S6SY761_REGULATOR_VDD,
S6SY761_REGULATOR_AVDD,
};
struct s6sy761_data {
struct i2c_client *client;
struct regulator_bulk_data regulators[2];
struct input_dev *input;
struct touchscreen_properties prop;
u8 data[S6SY761_EVENT_SIZE * S6SY761_EVENT_COUNT];
u16 devid;
u8 tx_channel;
};
/*
* We can't simply use i2c_smbus_read_i2c_block_data because we
* need to read more than 255 bytes
*/
static int s6sy761_read_events(struct s6sy761_data *sdata, u16 n_events)
{
u8 cmd = S6SY761_READ_ALL_EVENT;
struct i2c_msg msgs[2] = {
{
.addr = sdata->client->addr,
.len = 1,
.buf = &cmd,
},
{
.addr = sdata->client->addr,
.flags = I2C_M_RD,
.len = (n_events * S6SY761_EVENT_SIZE),
.buf = sdata->data + S6SY761_EVENT_SIZE,
},
};
int ret;
ret = i2c_transfer(sdata->client->adapter, msgs, ARRAY_SIZE(msgs));
if (ret < 0)
return ret;
return ret == ARRAY_SIZE(msgs) ? 0 : -EIO;
}
static void s6sy761_report_coordinates(struct s6sy761_data *sdata,
u8 *event, u8 tid)
{
u8 major = event[4];
u8 minor = event[5];
u8 z = event[6] & S6SY761_MASK_Z;
u16 x = (event[1] << 4) | ((event[3] & S6SY761_MASK_X) >> 4);
u16 y = (event[2] << 4) | (event[3] & S6SY761_MASK_Y);
input_mt_slot(sdata->input, tid);
input_mt_report_slot_state(sdata->input, MT_TOOL_FINGER, true);
input_report_abs(sdata->input, ABS_MT_POSITION_X, x);
input_report_abs(sdata->input, ABS_MT_POSITION_Y, y);
input_report_abs(sdata->input, ABS_MT_TOUCH_MAJOR, major);
input_report_abs(sdata->input, ABS_MT_TOUCH_MINOR, minor);
input_report_abs(sdata->input, ABS_MT_PRESSURE, z);
input_sync(sdata->input);
}
static void s6sy761_report_release(struct s6sy761_data *sdata,
u8 *event, u8 tid)
{
input_mt_slot(sdata->input, tid);
input_mt_report_slot_state(sdata->input, MT_TOOL_FINGER, false);
input_sync(sdata->input);
}
static void s6sy761_handle_coordinates(struct s6sy761_data *sdata, u8 *event)
{
u8 tid;
u8 touch_state;
if (unlikely(!(event[0] & S6SY761_MASK_TID)))
return;
tid = ((event[0] & S6SY761_MASK_TID) >> 2) - 1;
touch_state = (event[0] & S6SY761_MASK_TOUCH_STATE) >> 6;
switch (touch_state) {
case S6SY761_TS_NONE:
break;
case S6SY761_TS_RELEASE:
s6sy761_report_release(sdata, event, tid);
break;
case S6SY761_TS_PRESS:
case S6SY761_TS_MOVE:
s6sy761_report_coordinates(sdata, event, tid);
break;
}
}
static void s6sy761_handle_events(struct s6sy761_data *sdata, u8 n_events)
{
int i;
for (i = 0; i < n_events; i++) {
u8 *event = &sdata->data[i * S6SY761_EVENT_SIZE];
u8 event_id = event[0] & S6SY761_MASK_EID;
if (!event[0])
return;
switch (event_id) {
case S6SY761_EVENT_ID_COORDINATE:
s6sy761_handle_coordinates(sdata, event);
break;
case S6SY761_EVENT_ID_STATUS:
break;
default:
break;
}
}
}
static irqreturn_t s6sy761_irq_handler(int irq, void *dev)
{
struct s6sy761_data *sdata = dev;
int ret;
u8 n_events;
ret = i2c_smbus_read_i2c_block_data(sdata->client,
S6SY761_READ_ONE_EVENT,
S6SY761_EVENT_SIZE,
sdata->data);
if (ret < 0) {
dev_err(&sdata->client->dev, "failed to read events\n");
return IRQ_HANDLED;
}
if (!sdata->data[0])
return IRQ_HANDLED;
n_events = sdata->data[7] & S6SY761_MASK_LEFT_EVENTS;
if (unlikely(n_events > S6SY761_EVENT_COUNT - 1))
return IRQ_HANDLED;
if (n_events) {
ret = s6sy761_read_events(sdata, n_events);
if (ret < 0) {
dev_err(&sdata->client->dev, "failed to read events\n");
return IRQ_HANDLED;
}
}
s6sy761_handle_events(sdata, n_events + 1);
return IRQ_HANDLED;
}
static int s6sy761_input_open(struct input_dev *dev)
{
struct s6sy761_data *sdata = input_get_drvdata(dev);
return i2c_smbus_write_byte(sdata->client, S6SY761_SENSE_ON);
}
static void s6sy761_input_close(struct input_dev *dev)
{
struct s6sy761_data *sdata = input_get_drvdata(dev);
int ret;
ret = i2c_smbus_write_byte(sdata->client, S6SY761_SENSE_OFF);
if (ret)
dev_err(&sdata->client->dev, "failed to turn off sensing\n");
}
static ssize_t s6sy761_sysfs_devid(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct s6sy761_data *sdata = dev_get_drvdata(dev);
return sprintf(buf, "%#x\n", sdata->devid);
}
static DEVICE_ATTR(devid, 0444, s6sy761_sysfs_devid, NULL);
static struct attribute *s6sy761_sysfs_attrs[] = {
&dev_attr_devid.attr,
NULL
};
ATTRIBUTE_GROUPS(s6sy761_sysfs);
static int s6sy761_power_on(struct s6sy761_data *sdata)
{
u8 buffer[S6SY761_EVENT_SIZE];
u8 event;
int ret;
ret = regulator_bulk_enable(ARRAY_SIZE(sdata->regulators),
sdata->regulators);
if (ret)
return ret;
msleep(140);
/* double check whether the touch is functional */
ret = i2c_smbus_read_i2c_block_data(sdata->client,
S6SY761_READ_ONE_EVENT,
S6SY761_EVENT_SIZE,
buffer);
if (ret < 0)
return ret;
event = (buffer[0] >> 2) & 0xf;
if ((event != S6SY761_EVENT_INFO &&
event != S6SY761_EVENT_VENDOR_INFO) ||
buffer[1] != S6SY761_INFO_BOOT_COMPLETE) {
return -ENODEV;
}
ret = i2c_smbus_read_byte_data(sdata->client, S6SY761_BOOT_STATUS);
if (ret < 0)
return ret;
/* for some reasons the device might be stuck in the bootloader */
if (ret != S6SY761_BS_APPLICATION)
return -ENODEV;
/* enable touch functionality */
ret = i2c_smbus_write_word_data(sdata->client,
S6SY761_TOUCH_FUNCTION,
S6SY761_MASK_TOUCH);
if (ret)
return ret;
return 0;
}
static int s6sy761_hw_init(struct s6sy761_data *sdata,
unsigned int *max_x, unsigned int *max_y)
{
u8 buffer[S6SY761_PANEL_ID_SIZE]; /* larger read size */
int ret;
ret = s6sy761_power_on(sdata);
if (ret)
return ret;
ret = i2c_smbus_read_i2c_block_data(sdata->client,
S6SY761_DEVICE_ID,
S6SY761_DEVID_SIZE,
buffer);
if (ret < 0)
return ret;
sdata->devid = get_unaligned_be16(buffer + 1);
ret = i2c_smbus_read_i2c_block_data(sdata->client,
S6SY761_PANEL_INFO,
S6SY761_PANEL_ID_SIZE,
buffer);
if (ret < 0)
return ret;
*max_x = get_unaligned_be16(buffer);
*max_y = get_unaligned_be16(buffer + 2);
/* if no tx channels defined, at least keep one */
sdata->tx_channel = max_t(u8, buffer[8], 1);
ret = i2c_smbus_read_byte_data(sdata->client,
S6SY761_FIRMWARE_INTEGRITY);
if (ret < 0)
return ret;
else if (ret != S6SY761_FW_OK)
return -ENODEV;
return 0;
}
static void s6sy761_power_off(void *data)
{
struct s6sy761_data *sdata = data;
disable_irq(sdata->client->irq);
regulator_bulk_disable(ARRAY_SIZE(sdata->regulators),
sdata->regulators);
}
static int s6sy761_probe(struct i2c_client *client)
{
struct s6sy761_data *sdata;
unsigned int max_x, max_y;
int err;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_I2C_BLOCK))
return -ENODEV;
sdata = devm_kzalloc(&client->dev, sizeof(*sdata), GFP_KERNEL);
if (!sdata)
return -ENOMEM;
i2c_set_clientdata(client, sdata);
sdata->client = client;
sdata->regulators[S6SY761_REGULATOR_VDD].supply = "vdd";
sdata->regulators[S6SY761_REGULATOR_AVDD].supply = "avdd";
err = devm_regulator_bulk_get(&client->dev,
ARRAY_SIZE(sdata->regulators),
sdata->regulators);
if (err)
return err;
err = devm_add_action_or_reset(&client->dev, s6sy761_power_off, sdata);
if (err)
return err;
err = s6sy761_hw_init(sdata, &max_x, &max_y);
if (err)
return err;
sdata->input = devm_input_allocate_device(&client->dev);
if (!sdata->input)
return -ENOMEM;
sdata->input->name = S6SY761_DEV_NAME;
sdata->input->id.bustype = BUS_I2C;
sdata->input->open = s6sy761_input_open;
sdata->input->close = s6sy761_input_close;
input_set_abs_params(sdata->input, ABS_MT_POSITION_X, 0, max_x, 0, 0);
input_set_abs_params(sdata->input, ABS_MT_POSITION_Y, 0, max_y, 0, 0);
input_set_abs_params(sdata->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
input_set_abs_params(sdata->input, ABS_MT_TOUCH_MINOR, 0, 255, 0, 0);
input_set_abs_params(sdata->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
input_set_abs_params(sdata->input, ABS_MT_TOUCH_MINOR, 0, 255, 0, 0);
input_set_abs_params(sdata->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
touchscreen_parse_properties(sdata->input, true, &sdata->prop);
if (!input_abs_get_max(sdata->input, ABS_X) ||
!input_abs_get_max(sdata->input, ABS_Y)) {
dev_warn(&client->dev, "the axis have not been set\n");
}
err = input_mt_init_slots(sdata->input, sdata->tx_channel,
INPUT_MT_DIRECT);
if (err)
return err;
input_set_drvdata(sdata->input, sdata);
err = input_register_device(sdata->input);
if (err)
return err;
err = devm_request_threaded_irq(&client->dev, client->irq, NULL,
s6sy761_irq_handler,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"s6sy761_irq", sdata);
if (err)
return err;
pm_runtime_enable(&client->dev);
return 0;
}
static void s6sy761_remove(struct i2c_client *client)
{
pm_runtime_disable(&client->dev);
}
static int s6sy761_runtime_suspend(struct device *dev)
{
struct s6sy761_data *sdata = dev_get_drvdata(dev);
return i2c_smbus_write_byte_data(sdata->client,
S6SY761_APPLICATION_MODE, S6SY761_APP_SLEEP);
}
static int s6sy761_runtime_resume(struct device *dev)
{
struct s6sy761_data *sdata = dev_get_drvdata(dev);
return i2c_smbus_write_byte_data(sdata->client,
S6SY761_APPLICATION_MODE, S6SY761_APP_NORMAL);
}
static int s6sy761_suspend(struct device *dev)
{
struct s6sy761_data *sdata = dev_get_drvdata(dev);
s6sy761_power_off(sdata);
return 0;
}
static int s6sy761_resume(struct device *dev)
{
struct s6sy761_data *sdata = dev_get_drvdata(dev);
enable_irq(sdata->client->irq);
return s6sy761_power_on(sdata);
}
static const struct dev_pm_ops s6sy761_pm_ops = {
SYSTEM_SLEEP_PM_OPS(s6sy761_suspend, s6sy761_resume)
RUNTIME_PM_OPS(s6sy761_runtime_suspend, s6sy761_runtime_resume, NULL)
};
#ifdef CONFIG_OF
static const struct of_device_id s6sy761_of_match[] = {
{ .compatible = "samsung,s6sy761", },
{ },
};
MODULE_DEVICE_TABLE(of, s6sy761_of_match);
#endif
static const struct i2c_device_id s6sy761_id[] = {
{ "s6sy761" },
{ }
};
MODULE_DEVICE_TABLE(i2c, s6sy761_id);
static struct i2c_driver s6sy761_driver = {
.driver = {
.name = S6SY761_DEV_NAME,
.dev_groups = s6sy761_sysfs_groups,
.of_match_table = of_match_ptr(s6sy761_of_match),
.pm = pm_ptr(&s6sy761_pm_ops),
},
.probe = s6sy761_probe,
.remove = s6sy761_remove,
.id_table = s6sy761_id,
};
module_i2c_driver(s6sy761_driver);
MODULE_AUTHOR("Andi Shyti <[email protected]>");
MODULE_DESCRIPTION("Samsung S6SY761 Touch Screen");
MODULE_LICENSE("GPL v2");
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