Re: [PATCH v3 2/2] Input: add support for the STMicroelectronics FingerTip touchscreen

From: Andi Shyti
Date: Fri Apr 07 2017 - 05:32:02 EST


Hi Dmitry,

just a kind ping, do you have any comment about this?

Thanks,
Andi

On Mon, Mar 27, 2017 at 10:07:43PM +0900, Andi Shyti wrote:
> The stmfts (ST-Microelectronics FingerTip S) touchscreen device
> is a capacitive multi-touch controller mainly for mobile use.
>
> It's connected through i2c bus at the address 0x49 and it
> interfaces with userspace through input event interface.
>
> At the current state it provides a touchscreen multitouch
> functionality up to 10 fingers. Each finger is enumerated with a
> distinctive id (from 0 to 9).
>
> If enabled the device can support single "touch" hovering, by
> providing three coordinates, x, y and distance.
>
> It is possible to select the touchkey functionality which
> provides a basic two keys interface for "home" and "back" menu,
> typical in mobile phones.
>
> Signed-off-by: Andi Shyti <andi.shyti@xxxxxxxxxxx>
> ---
> drivers/input/touchscreen/Kconfig | 12 +
> drivers/input/touchscreen/Makefile | 1 +
> drivers/input/touchscreen/stmfts.c | 805 +++++++++++++++++++++++++++++++++++++
> 3 files changed, 818 insertions(+)
> create mode 100644 drivers/input/touchscreen/stmfts.c
>
> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
> index 33c62e5de4fa..f8631c64290d 100644
> --- a/drivers/input/touchscreen/Kconfig
> +++ b/drivers/input/touchscreen/Kconfig
> @@ -1114,6 +1114,18 @@ config TOUCHSCREEN_ST1232
> To compile this driver as a module, choose M here: the
> module will be called st1232_ts.
>
> +config TOUCHSCREEN_STMFTS
> + tristate "STMicroelectronics STMFTS touchscreen"
> + depends on I2C
> + depends on INPUT
> + depends on LEDS_CLASS
> + help
> + Say Y here if you want support for STMicroelectronics
> + STMFTS touchscreen.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called stmfts.
> +
> config TOUCHSCREEN_STMPE
> tristate "STMicroelectronics STMPE touchscreens"
> depends on MFD_STMPE
> diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
> index 18e476948e44..6badce87037b 100644
> --- a/drivers/input/touchscreen/Makefile
> +++ b/drivers/input/touchscreen/Makefile
> @@ -67,6 +67,7 @@ obj-$(CONFIG_TOUCHSCREEN_S3C2410) += s3c2410_ts.o
> obj-$(CONFIG_TOUCHSCREEN_SILEAD) += silead.o
> obj-$(CONFIG_TOUCHSCREEN_SIS_I2C) += sis_i2c.o
> obj-$(CONFIG_TOUCHSCREEN_ST1232) += st1232.o
> +obj-$(CONFIG_TOUCHSCREEN_STMFTS) += stmfts.o
> obj-$(CONFIG_TOUCHSCREEN_STMPE) += stmpe-ts.o
> obj-$(CONFIG_TOUCHSCREEN_SUN4I) += sun4i-ts.o
> obj-$(CONFIG_TOUCHSCREEN_SUR40) += sur40.o
> diff --git a/drivers/input/touchscreen/stmfts.c b/drivers/input/touchscreen/stmfts.c
> new file mode 100644
> index 000000000000..2e18b1456f42
> --- /dev/null
> +++ b/drivers/input/touchscreen/stmfts.c
> @@ -0,0 +1,805 @@
> +/*
> + * Copyright (c) 2017 Samsung Electronics Co., Ltd.
> + * Author: Andi Shyti <andi.shyti@xxxxxxxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * STMicroelectronics FTS Touchscreen device driver
> + */
> +
> +#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/leds.h>
> +#include <linux/module.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/regulator/consumer.h>
> +
> +/* I2C commands */
> +#define STMFTS_READ_INFO 0x80
> +#define STMFTS_READ_STATUS 0x84
> +#define STMFTS_READ_ONE_EVENT 0x85
> +#define STMFTS_READ_ALL_EVENT 0x86
> +#define STMFTS_LATEST_EVENT 0x87
> +#define STMFTS_SLEEP_IN 0x90
> +#define STMFTS_SLEEP_OUT 0x91
> +#define STMFTS_MS_MT_SENSE_OFF 0x92
> +#define STMFTS_MS_MT_SENSE_ON 0x93
> +#define STMFTS_SS_HOVER_SENSE_OFF 0x94
> +#define STMFTS_SS_HOVER_SENSE_ON 0x95
> +#define STMFTS_MS_KEY_SENSE_OFF 0x9a
> +#define STMFTS_MS_KEY_SENSE_ON 0x9b
> +#define STMFTS_SYSTEM_RESET 0xa0
> +#define STMFTS_CLEAR_EVENT_STACK 0xa1
> +#define STMFTS_FULL_FORCE_CALIBRATION 0xa2
> +#define STMFTS_MS_CX_TUNING 0xa3
> +#define STMFTS_SS_CX_TUNING 0xa4
> +
> +/* events */
> +#define STMFTS_EV_NO_EVENT 0x00
> +#define STMFTS_EV_MULTI_TOUCH_DETECTED 0x02
> +#define STMFTS_EV_MULTI_TOUCH_ENTER 0x03
> +#define STMFTS_EV_MULTI_TOUCH_LEAVE 0x04
> +#define STMFTS_EV_MULTI_TOUCH_MOTION 0x05
> +#define STMFTS_EV_HOVER_ENTER 0x07
> +#define STMFTS_EV_HOVER_LEAVE 0x08
> +#define STMFTS_EV_HOVER_MOTION 0x09
> +#define STMFTS_EV_KEY_STATUS 0x0e
> +#define STMFTS_EV_ERROR 0x0f
> +#define STMFTS_EV_CONTROLLER_READY 0x10
> +#define STMFTS_EV_SLEEP_OUT_CONTROLLER_READY 0x11
> +#define STMFTS_EV_STATUS 0x16
> +#define STMFTS_EV_DEBUG 0xdb
> +
> +/* multi touch related event masks */
> +#define STMFTS_MASK_EVENT_ID 0x0f
> +#define STMFTS_MASK_TOUCH_ID 0xf0
> +#define STMFTS_MASK_LEFT_EVENT 0x0f
> +#define STMFTS_MASK_X_MSB 0x0f
> +#define STMFTS_MASK_Y_LSB 0xf0
> +
> +/* key related event masks */
> +#define STMFTS_MASK_KEY_NO_TOUCH 0x00
> +#define STMFTS_MASK_KEY_MENU 0x01
> +#define STMFTS_MASK_KEY_BACK 0x02
> +
> +#define STMFTS_EVENT_SIZE 8
> +#define STMFTS_STACK_DEPTH 32
> +#define STMFTS_DATA_MAX_SIZE (STMFTS_EVENT_SIZE * STMFTS_STACK_DEPTH)
> +#define STMFTS_MAX_FINGERS 10
> +#define STMFTS_DEV_NAME "stmfts"
> +
> +enum stmfts_regulators {
> + STMFTS_REGULATOR_VDD,
> + STMFTS_REGULATOR_AVDD,
> +};
> +
> +struct stmfts_data {
> + struct i2c_client *client;
> + struct input_dev *input;
> + struct led_classdev led_cdev;
> + struct mutex mutex;
> +
> + struct touchscreen_properties prop;
> +
> + struct regulator_bulk_data regulators[2];
> +
> + /* ledvdd will be used also to check
> + * whether the LED is supported
> + */
> + struct regulator *ledvdd;
> +
> + u16 chip_id;
> + u8 chip_ver;
> + u16 fw_ver;
> + u8 config_id;
> + u8 config_ver;
> +
> + u8 data[STMFTS_DATA_MAX_SIZE];
> +
> + struct completion signal;
> +
> + bool use_key;
> + bool led_status;
> + bool hover_enabled;
> + bool running;
> +};
> +
> +static int stmfts_read_i2c_block_data(struct stmfts_data *sdata)
> +{
> + struct i2c_msg msgs[2];
> + u8 cmd = STMFTS_READ_ALL_EVENT;
> +
> + msgs[0].addr = sdata->client->addr;
> + msgs[0].flags = 0;
> + msgs[0].len = 1;
> + msgs[0].buf = &cmd;
> +
> + msgs[1].addr = sdata->client->addr;
> + msgs[1].flags = I2C_M_RD;
> + msgs[1].len = STMFTS_DATA_MAX_SIZE - STMFTS_EVENT_SIZE;
> + msgs[1].buf = sdata->data + STMFTS_EVENT_SIZE;
> +
> + return i2c_transfer(sdata->client->adapter, msgs, ARRAY_SIZE(msgs));
> +}
> +
> +static void stmfts_brightness_set(struct led_classdev *led_cdev,
> + enum led_brightness value)
> +{
> + struct stmfts_data *sdata = container_of(led_cdev,
> + struct stmfts_data, led_cdev);
> +
> + if (value == sdata->led_status || !sdata->ledvdd)
> + return;
> +
> + if (!value) {
> + regulator_disable(sdata->ledvdd);
> + } else {
> + int err = regulator_enable(sdata->ledvdd);
> +
> + if (err)
> + dev_warn(&sdata->client->dev,
> + "failed to disable ledvdd regulator\n");
> + }
> +
> + sdata->led_status = value;
> +}
> +
> +static enum led_brightness stmfts_brightness_get(struct led_classdev *led_cdev)
> +{
> + struct stmfts_data *sdata = container_of(led_cdev,
> + struct stmfts_data, led_cdev);
> +
> + return !!regulator_is_enabled(sdata->ledvdd);
> +}
> +
> +static void stmfts_parse_event(struct stmfts_data *sdata)
> +{
> + u8 id, t_id;
> + u16 x, y, z, maj, min, orientation, area;
> + u8 *event;
> + int i;
> +
> + for (i = 0; i < STMFTS_STACK_DEPTH; i++) {
> + event = &sdata->data[i*STMFTS_EVENT_SIZE];
> +
> + id = event[0] & STMFTS_MASK_EVENT_ID;
> + t_id = (event[0] & STMFTS_MASK_TOUCH_ID) >> 4;
> +
> + switch (id) {
> + case STMFTS_EV_NO_EVENT:
> + return;
> +
> + case STMFTS_EV_MULTI_TOUCH_ENTER:
> + case STMFTS_EV_MULTI_TOUCH_LEAVE:
> + case STMFTS_EV_MULTI_TOUCH_MOTION:
> + if (id == STMFTS_EV_MULTI_TOUCH_ENTER)
> + input_mt_report_slot_state(sdata->input,
> + MT_TOOL_FINGER, true);
> + else if (id == STMFTS_EV_MULTI_TOUCH_LEAVE)
> + input_mt_report_slot_state(sdata->input,
> + MT_TOOL_FINGER, false);
> +
> + x = event[1] | ((event[2] & STMFTS_MASK_X_MSB) << 8);
> + y = (event[2] >> 4) | (event[3] << 4);
> +
> + maj = event[4];
> + min = event[5];
> + orientation = event[6];
> + area = event[7];
> +
> + input_mt_slot(sdata->input, t_id);
> + 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, maj);
> + input_report_abs(sdata->input, ABS_MT_TOUCH_MINOR, min);
> + input_report_abs(sdata->input, ABS_MT_PRESSURE, area);
> + input_report_abs(sdata->input, ABS_MT_ORIENTATION,
> + orientation);
> + input_sync(sdata->input);
> +
> + break;
> +
> + case STMFTS_EV_HOVER_ENTER:
> + case STMFTS_EV_HOVER_LEAVE:
> + case STMFTS_EV_HOVER_MOTION:
> + x = (event[2] << 4) | (event[4] >> 4);
> + y = (event[3] << 4) | (event[4] & STMFTS_MASK_Y_LSB);
> + z = event[5];
> + orientation = event[6] & STMFTS_MASK_Y_LSB;
> +
> + input_report_abs(sdata->input, ABS_X, x);
> + input_report_abs(sdata->input, ABS_Y, y);
> + input_report_abs(sdata->input, ABS_DISTANCE, z);
> + input_sync(sdata->input);
> +
> + break;
> +
> + case STMFTS_EV_KEY_STATUS:
> + switch (event[2]) {
> + case 0:
> + input_report_key(sdata->input, KEY_BACK, 0);
> + input_report_key(sdata->input, KEY_MENU, 0);
> + break;
> +
> + case STMFTS_MASK_KEY_BACK:
> + input_report_key(sdata->input, KEY_BACK, 1);
> + break;
> +
> + case STMFTS_MASK_KEY_MENU:
> + input_report_key(sdata->input, KEY_MENU, 1);
> + break;
> +
> + default:
> + dev_warn(&sdata->client->dev,
> + "unknown key event\n");
> + }
> +
> + input_sync(sdata->input);
> + break;
> +
> + case STMFTS_EV_ERROR:
> + dev_warn(&sdata->client->dev,
> + "error code: 0x%x%x%x%x%x%x",
> + event[6], event[5], event[4],
> + event[3], event[2], event[1]);
> + break;
> +
> + default:
> + dev_err(&sdata->client->dev,
> + "unknown event 0x%x\n", event[0]);
> + }
> + }
> +}
> +
> +static irqreturn_t stmfts_irq_handler(int irq, void *dev)
> +{
> + struct stmfts_data *sdata = dev;
> + int ret;
> +
> + mutex_lock(&sdata->mutex);
> + ret = i2c_smbus_read_i2c_block_data(sdata->client,
> + STMFTS_READ_ONE_EVENT,
> + STMFTS_EVENT_SIZE, sdata->data);
> +
> + if (ret < 0 || ret != STMFTS_EVENT_SIZE)
> + goto exit;
> +
> + switch (sdata->data[0]) {
> + case STMFTS_EV_CONTROLLER_READY:
> + case STMFTS_EV_SLEEP_OUT_CONTROLLER_READY:
> + case STMFTS_EV_STATUS:
> + complete(&sdata->signal);
> + case STMFTS_EV_NO_EVENT:
> + case STMFTS_EV_DEBUG:
> + break;
> +
> + default:
> + if (unlikely(!sdata->input))
> + goto exit;
> +
> + ret = stmfts_read_i2c_block_data(sdata);
> + if (ret < 0)
> + goto exit;
> +
> + stmfts_parse_event(sdata);
> + }
> +
> +exit:
> + mutex_unlock(&sdata->mutex);
> + return IRQ_HANDLED;
> +}
> +
> +static int stmfts_write_and_wait(struct stmfts_data *sdata, const u8 cmd)
> +{
> + int err;
> +
> + err = i2c_smbus_write_byte(sdata->client, cmd);
> + if (err)
> + return err;
> +
> + err = wait_for_completion_timeout(&sdata->signal,
> + msecs_to_jiffies(1000));
> +
> + return !err ? -ETIMEDOUT : 0;
> +}
> +
> +static int stmfts_input_open(struct input_dev *dev)
> +{
> + int ret;
> + struct stmfts_data *sdata = input_get_drvdata(dev);
> +
> + ret = pm_runtime_get_sync(&sdata->client->dev);
> + if (ret < 0)
> + return ret;
> +
> + ret = i2c_smbus_write_byte(sdata->client, STMFTS_MS_MT_SENSE_ON);
> + if (ret)
> + return ret;
> +
> + mutex_lock(&sdata->mutex);
> + sdata->running = true;
> +
> + if (sdata->hover_enabled) {
> + ret = i2c_smbus_write_byte(sdata->client,
> + STMFTS_SS_HOVER_SENSE_ON);
> + if (ret)
> + dev_warn(&sdata->client->dev,
> + "failed to enable hover\n");
> + }
> + mutex_unlock(&sdata->mutex);
> +
> + if (sdata->use_key) {
> + ret = i2c_smbus_write_byte(sdata->client,
> + STMFTS_MS_KEY_SENSE_ON);
> + if (ret)
> + /* I can still use only the touch screen */
> + dev_warn(&sdata->client->dev,
> + "failed to enable touchkey\n");
> + }
> +
> + return 0;
> +}
> +
> +static void stmfts_input_close(struct input_dev *dev)
> +{
> + int ret;
> + struct stmfts_data *sdata = input_get_drvdata(dev);
> +
> + ret = i2c_smbus_write_byte(sdata->client, STMFTS_MS_MT_SENSE_OFF);
> + if (ret)
> + dev_warn(&sdata->client->dev,
> + "failed to disable touchscreen\n");
> +
> + mutex_lock(&sdata->mutex);
> + sdata->running = false;
> +
> + if (sdata->hover_enabled) {
> + ret = i2c_smbus_write_byte(sdata->client,
> + STMFTS_SS_HOVER_SENSE_OFF);
> + if (ret)
> + dev_warn(&sdata->client->dev,
> + "failed to disable hover\n");
> + }
> + mutex_unlock(&sdata->mutex);
> +
> + if (sdata->use_key) {
> + i2c_smbus_write_byte(sdata->client, STMFTS_MS_KEY_SENSE_OFF);
> + if (ret)
> + dev_warn(&sdata->client->dev,
> + "failed to disable touchkey\n");
> + }
> +
> + pm_runtime_put_sync(&sdata->client->dev);
> +}
> +
> +static ssize_t stmfts_sysfs_chip_id(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "0x%x\n", sdata->chip_id);
> +}
> +
> +static ssize_t stmfts_sysfs_chip_version(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "%u\n", sdata->chip_ver);
> +}
> +
> +static ssize_t stmfts_sysfs_fw_ver(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "%u\n", sdata->fw_ver);
> +}
> +
> +static ssize_t stmfts_sysfs_config_id(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "0x%x\n", sdata->config_id);
> +}
> +
> +static ssize_t stmfts_sysfs_config_version(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "%u\n", sdata->config_ver);
> +}
> +
> +static ssize_t stmfts_sysfs_read_status(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> + u8 status[4];
> + int ret;
> +
> + ret = i2c_smbus_read_i2c_block_data(sdata->client,
> + STMFTS_READ_STATUS, 4, status);
> +
> + return sprintf(buf, "0x%x\n", status[0]);
> +}
> +
> +static ssize_t stmfts_sysfs_hover_enable_read(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return sprintf(buf, "%u\n", sdata->hover_enabled);
> +}
> +
> +static ssize_t stmfts_sysfs_hover_enable_write(struct device *dev,
> + struct device_attribute *attr,
> + const char *buf, size_t len)
> +{
> + unsigned long value;
> + int err;
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + if (kstrtoul(buf, 0, &value))
> + return -EINVAL;
> +
> + mutex_lock(&sdata->mutex);
> +
> + if (value & sdata->hover_enabled)
> + goto out;
> +
> + if (!sdata->running) {
> + sdata->hover_enabled = !!value;
> + goto out;
> + }
> +
> + if (value) {
> + err = i2c_smbus_write_byte(sdata->client,
> + STMFTS_SS_HOVER_SENSE_ON);
> + sdata->hover_enabled = !err;
> + } else {
> + err = i2c_smbus_write_byte(sdata->client,
> + STMFTS_SS_HOVER_SENSE_OFF);
> + sdata->hover_enabled = !!err;
> + }
> +
> + if (err)
> + dev_warn(&sdata->client->dev, "failed to %s hover\n",
> + value ? "enable" : "disable");
> +out:
> + mutex_unlock(&sdata->mutex);
> +
> + return len;
> +}
> +
> +static DEVICE_ATTR(chip_id, 0444, stmfts_sysfs_chip_id, NULL);
> +static DEVICE_ATTR(chip_version, 0444, stmfts_sysfs_chip_version, NULL);
> +static DEVICE_ATTR(fw_ver, 0444, stmfts_sysfs_fw_ver, NULL);
> +static DEVICE_ATTR(config_id, 0444, stmfts_sysfs_config_id, NULL);
> +static DEVICE_ATTR(config_version, 0444, stmfts_sysfs_config_version, NULL);
> +static DEVICE_ATTR(status, 0444, stmfts_sysfs_read_status, NULL);
> +static DEVICE_ATTR(hover_enable, 0644, stmfts_sysfs_hover_enable_read,
> + stmfts_sysfs_hover_enable_write);
> +
> +static struct attribute *stmfts_sysfs_attrs[] = {
> + &dev_attr_chip_id.attr,
> + &dev_attr_chip_version.attr,
> + &dev_attr_fw_ver.attr,
> + &dev_attr_config_id.attr,
> + &dev_attr_config_version.attr,
> + &dev_attr_status.attr,
> + &dev_attr_hover_enable.attr,
> + NULL
> +};
> +
> +static struct attribute_group stmfts_attribute_group = {
> + .attrs = stmfts_sysfs_attrs
> +};
> +
> +static int stmfts_power_on(struct stmfts_data *sdata)
> +{
> + int err;
> + u8 reg[8];
> +
> + err = regulator_bulk_enable(ARRAY_SIZE(sdata->regulators),
> + sdata->regulators);
> + if (err)
> + return err;
> +
> + /*
> + * the datasheet does not specify the power on time, but considering
> + * that the reset time is < 10ms, I sleep 20ms to be sure
> + */
> + msleep(20);
> +
> + err = i2c_smbus_read_i2c_block_data(sdata->client,
> + STMFTS_READ_INFO, 8, reg);
> + if (err < 0)
> + return err;
> + if (err != 8)
> + return -EIO;
> +
> + sdata->chip_id = (reg[6] << 8) | reg[7];
> + sdata->chip_ver = reg[0];
> + sdata->fw_ver = (reg[2] << 8) | reg[3];
> + sdata->config_id = reg[4];
> + sdata->config_ver = reg[5];
> +
> + reinit_completion(&sdata->signal);
> +
> + enable_irq(sdata->client->irq);
> + err = stmfts_write_and_wait(sdata, STMFTS_SYSTEM_RESET);
> + if (err)
> + return err;
> +
> + err = stmfts_write_and_wait(sdata, STMFTS_SLEEP_OUT);
> + if (err)
> + return err;
> +
> + /* optional tuning */
> + err = stmfts_write_and_wait(sdata, STMFTS_MS_CX_TUNING);
> + if (err)
> + dev_warn(&sdata->client->dev, "failed to perform mutual auto tune\n");
> +
> + /* optional tuning */
> + err = stmfts_write_and_wait(sdata, STMFTS_SS_CX_TUNING);
> + if (err)
> + dev_warn(&sdata->client->dev, "failed to perform self auto tune\n");
> +
> + err = stmfts_write_and_wait(sdata, STMFTS_FULL_FORCE_CALIBRATION);
> + if (err)
> + return err;
> +
> + /* at this point no one is using the touchscreen
> + * and I don't really care about the return value
> + */
> + i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_IN);
> +
> + return 0;
> +}
> +
> +static void stmfts_power_off(void *data)
> +{
> + struct stmfts_data *sdata = data;
> +
> + disable_irq(sdata->client->irq);
> + regulator_bulk_disable(ARRAY_SIZE(sdata->regulators),
> + sdata->regulators);
> +}
> +
> +/* This function is void because I don't want to prevent using the touch key
> + * only because the LEDs don't get registered
> + */
> +static int stmfts_enable_led(struct stmfts_data *sdata)
> +{
> + int err;
> +
> + /* get the regulator for powering the leds on */
> + sdata->ledvdd = devm_regulator_get(&sdata->client->dev, "ledvdd");
> + if (IS_ERR(sdata->ledvdd))
> + return PTR_ERR(sdata->ledvdd);
> +
> + sdata->led_cdev.name = STMFTS_DEV_NAME;
> + sdata->led_cdev.max_brightness = LED_ON;
> + sdata->led_cdev.brightness = LED_OFF;
> + sdata->led_cdev.brightness_set = stmfts_brightness_set;
> + sdata->led_cdev.brightness_get = stmfts_brightness_get;
> +
> + err = devm_led_classdev_register(&sdata->client->dev, &sdata->led_cdev);
> + if (err) {
> + devm_regulator_put(sdata->ledvdd);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +static int stmfts_probe(struct i2c_client *client,
> + const struct i2c_device_id *id)
> +{
> + int err;
> + struct stmfts_data *sdata;
> +
> + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C |
> + I2C_FUNC_SMBUS_BYTE_DATA |
> + I2C_FUNC_SMBUS_I2C_BLOCK))
> + return -ENODEV;
> +
> + if (!client->dev.of_node)
> + return -ENOENT;
> +
> + sdata = devm_kzalloc(&client->dev, sizeof(*sdata), GFP_KERNEL);
> + if (!sdata)
> + return -ENOMEM;
> +
> + i2c_set_clientdata(client, sdata);
> +
> + mutex_init(&sdata->mutex);
> +
> + sdata->regulators[STMFTS_REGULATOR_VDD].supply = "vdd";
> + sdata->regulators[STMFTS_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, stmfts_power_off, sdata);
> + if (err)
> + return err;
> +
> + sdata->client = client;
> +
> + init_completion(&sdata->signal);
> +
> + /*
> + * Do not enable interrupts by default.
> + * One possible case when an IRQ can be already rased is e.g. if the
> + * regulator is set as always on and the stmfts device sends an IRQ as
> + * soon as it gets powered, de-synchronizing the power on sequence.
> + * During power on, the device will be reset and all the initialization
> + * IRQ will be resent.
> + */
> + irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
> + err = devm_request_threaded_irq(&client->dev, client->irq,
> + NULL, stmfts_irq_handler,
> + IRQF_ONESHOT | IRQF_TRIGGER_LOW,
> + "stmfts_irq", sdata);
> + if (err)
> + return err;
> +
> + dev_info(&client->dev, "initializing ST-Microelectronics FTS...\n");
> + err = stmfts_power_on(sdata);
> + if (err)
> + return err;
> +
> + sdata->use_key = of_property_read_bool(client->dev.of_node,
> + "touch-key-connected");
> +
> + sdata->input = devm_input_allocate_device(&client->dev);
> + if (!sdata->input)
> + return -ENOMEM;
> +
> + sdata->input->name = STMFTS_DEV_NAME;
> + sdata->input->id.bustype = BUS_I2C;
> + sdata->input->open = stmfts_input_open;
> + sdata->input->close = stmfts_input_close;
> +
> + touchscreen_parse_properties(sdata->input, true, &sdata->prop);
> +
> + input_set_abs_params(sdata->input, ABS_MT_POSITION_X, 0,
> + sdata->prop.max_x, 0, 0);
> + input_set_abs_params(sdata->input, ABS_MT_POSITION_Y, 0,
> + sdata->prop.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_ORIENTATION, 0, 255, 0, 0);
> + input_set_abs_params(sdata->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
> + input_set_abs_params(sdata->input, ABS_DISTANCE, 0, 255, 0, 0);
> +
> + if (sdata->use_key) {
> + input_set_capability(sdata->input, EV_KEY, KEY_MENU);
> + input_set_capability(sdata->input, EV_KEY, KEY_BACK);
> + }
> +
> + err = input_mt_init_slots(sdata->input,
> + STMFTS_MAX_FINGERS, INPUT_MT_DIRECT);
> + if (err)
> + return err;
> +
> + input_set_drvdata(sdata->input, sdata);
> + err = input_register_device(sdata->input);
> + if (err)
> + return err;
> +
> + if (sdata->use_key) {
> + err = stmfts_enable_led(sdata);
> + if (err) {
> + /* even if the LEDs have failed to be initialized and
> + * used in the driver, I can still use the device even
> + * without LEDs. The ledvdd regulator pointer will be
> + * used as a flag.
> + */
> + dev_warn(&client->dev,
> + "unable to use touchkey leds\n");
> + sdata->ledvdd = NULL;
> + }
> + }
> +
> + err = sysfs_create_group(&sdata->client->dev.kobj,
> + &stmfts_attribute_group);
> + if (err)
> + return err;
> +
> + pm_runtime_enable(&client->dev);
> +
> + return 0;
> +}
> +
> +static int stmfts_remove(struct i2c_client *client)
> +{
> + pm_runtime_disable(&client->dev);
> + sysfs_remove_group(&client->dev.kobj, &stmfts_attribute_group);
> +
> + return 0;
> +}
> +
> +static int stmfts_runtime_suspend(struct device *dev)
> +{
> + int ret;
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + ret = i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_IN);
> + if (ret)
> + dev_warn(dev, "failed to suspend device\n");
> +
> + return ret;
> +}
> +
> +static int stmfts_runtime_resume(struct device *dev)
> +{
> + int ret;
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + ret = i2c_smbus_write_byte(sdata->client, STMFTS_SLEEP_OUT);
> + if (ret)
> + dev_err(dev, "failed to resume device\n");
> +
> + return ret;
> +}
> +
> +static int __maybe_unused stmfts_suspend(struct device *dev)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + stmfts_power_off(sdata);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused stmfts_resume(struct device *dev)
> +{
> + struct stmfts_data *sdata = dev_get_drvdata(dev);
> +
> + return stmfts_power_on(sdata);
> +}
> +
> +static const struct dev_pm_ops stmfts_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(stmfts_suspend, stmfts_resume)
> + SET_RUNTIME_PM_OPS(stmfts_runtime_suspend, stmfts_runtime_resume, NULL)
> +};
> +
> +static const struct of_device_id stmfts_of_match[] = {
> + { .compatible = "st,stmfts", },
> + { },
> +};
> +MODULE_DEVICE_TABLE(of, stmfts_of_match);
> +
> +static const struct i2c_device_id stmfts_id[] = {
> + { "stmfts", 0 },
> + { },
> +};
> +MODULE_DEVICE_TABLE(i2c, stmfts_id);
> +
> +static struct i2c_driver stmfts_driver = {
> + .driver = {
> + .name = STMFTS_DEV_NAME,
> + .of_match_table = of_match_ptr(stmfts_of_match),
> + .pm = &stmfts_pm_ops,
> + },
> + .probe = stmfts_probe,
> + .remove = stmfts_remove,
> + .id_table = stmfts_id,
> +};
> +
> +module_i2c_driver(stmfts_driver);
> +
> +MODULE_AUTHOR("Andi Shyti <andi.shyti@xxxxxxxxxxx>");
> +MODULE_DESCRIPTION("STMicroelectronics FTS Touch Screen");
> +MODULE_LICENSE("GPL v2");
> --
> 2.11.0
>