Re: [PATCH 4/7] drivers: leds: Add the iEi WT61P803 PUZZLE LED driver

Andy Shevchenko
2020-09-09T09:30:35Z

On Sat, Sep 5, 2020 at 4:10 PM Luka Kovacic <luka.kovacic@sartura.hr> wrote:
>
> Add support for the iEi WT61P803 PUZZLE LED driver.
> Currently only the front panel power LED is supported.
>
> This driver depends on the iEi WT61P803 PUZZLE MFD driver.

Can we make it OF independent?
See below how to achieve this.

> Signed-off-by: Luka Kovacic <luka.kovacic@sartura.hr>
> Cc: Luka Perkov <luka.perkov@sartura.hr>
> ---
> drivers/leds/Kconfig | 8 ++
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-iei-wt61p803-puzzle.c | 184 ++++++++++++++++++++++++
> 3 files changed, 193 insertions(+)
> create mode 100644 drivers/leds/leds-iei-wt61p803-puzzle.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 1c181df24eae..8a25fb753dec 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -332,6 +332,14 @@ config LEDS_IPAQ_MICRO
> Choose this option if you want to use the notification LED on
> Compaq/HP iPAQ h3100 and h3600.
>
> +config LEDS_IEI_WT61P803_PUZZLE
> + tristate "LED Support for the iEi WT61P803 PUZZLE MCU"
> + depends on LEDS_CLASS
> + depends on MFD_IEI_WT61P803_PUZZLE
> + help
> + This option enables support for LEDs controlled by the iEi WT61P803
> + M801 MCU.
> +
> config LEDS_HP6XX
> tristate "LED Support for the HP Jornada 6xx"
> depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index c2c7d7ade0d0..cd362437fefd 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -34,6 +34,7 @@ obj-$(CONFIG_LEDS_HP6XX) += leds-hp6xx.o
> obj-$(CONFIG_LEDS_INTEL_SS4200) += leds-ss4200.o
> obj-$(CONFIG_LEDS_IP30) += leds-ip30.o
> obj-$(CONFIG_LEDS_IPAQ_MICRO) += leds-ipaq-micro.o
> +obj-$(CONFIG_LEDS_IEI_WT61P803_PUZZLE) += leds-iei-wt61p803-puzzle.o
> obj-$(CONFIG_LEDS_IS31FL319X) += leds-is31fl319x.o
> obj-$(CONFIG_LEDS_IS31FL32XX) += leds-is31fl32xx.o
> obj-$(CONFIG_LEDS_KTD2692) += leds-ktd2692.o
> diff --git a/drivers/leds/leds-iei-wt61p803-puzzle.c b/drivers/leds/leds-iei-wt61p803-puzzle.c
> new file mode 100644
> index 000000000000..50d1e4e81571
> --- /dev/null
> +++ b/drivers/leds/leds-iei-wt61p803-puzzle.c
> @@ -0,0 +1,184 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +/* iEi WT61P803 PUZZLE MCU LED Driver
> + *
> + * Copyright (C) 2020 Sartura Ltd.
> + * Author: Luka Kovacic <luka.kovacic@sartura.hr>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/mfd/iei-wt61p803-puzzle.h>

> +#include <linux/of.h>
> +#include <linux/of_device.h>

of*.h -> mod_devicetable.h

> +#include <linux/platform_device.h>

+ property.h

> +#include <linux/slab.h>
> +
> +#include <linux/leds.h>
> +
> +#define CMD_CHAR(x) (char)(x)
> +
> +/**
> + * enum iei_wt61p803_puzzle_led_state - LED state values

> + *

This is not needed.

> + * @IEI_LED_OFF: The LED is turned off
> + * @IEI_LED_ON: The LED is turned on
> + * @IEI_LED_BLINK_5HZ: The LED will blink with a freq of 5 Hz
> + * @IEI_LED_BLINK_1HZ: The LED will blink with a freq of 1 Hz
> + */
> +enum iei_wt61p803_puzzle_led_state {
> + IEI_LED_OFF = 0x30,
> + IEI_LED_ON = 0x31,
> + IEI_LED_BLINK_5HZ = 0x32,
> + IEI_LED_BLINK_1HZ = 0x33

Can we leave a comma here?

> +};
> +
> +/**
> + * struct iei_wt61p803_puzzle_led - MCU LED Driver

> + *

This is not needed.

> + * @mcu: MCU struct pointer
> + * @lock: General mutex lock for LED operations
> + * @led_power_state: State of the front panel power LED
> + */
> +struct iei_wt61p803_puzzle_led {
> + struct iei_wt61p803_puzzle *mcu;
> + struct mutex lock;
> +
> + int led_power_state;
> +};
> +
> +static inline struct iei_wt61p803_puzzle_led *
> + cdev_to_iei_wt61p803_puzzle_led(struct led_classdev *led_cdev)

It's a rather strange indentation.

> +{
> + return dev_get_drvdata(led_cdev->dev->parent);
> +}
> +
> +static int iei_wt61p803_puzzle_led_brightness_set_blocking
> + (struct led_classdev *cdev, enum led_brightness brightness)

Ditto.

> +{
> + struct iei_wt61p803_puzzle_led *mcu_led =
> + cdev_to_iei_wt61p803_puzzle_led(cdev);

> + unsigned char led_power_cmd[5] = { '@', 'R', '1',
> + CMD_CHAR(IEI_LED_OFF) };

Ditto.

> +

This is not needed.

> + int ret;

> +

Ditto.

> + size_t reply_size = 0;

> + unsigned char *resp_buf = kmalloc(IEI_WT61P803_PUZZLE_BUF_SIZE, GFP_KERNEL);

Please move the assignment closer to its use and add an error check.
Btw, how big is the buffer?

> + mutex_lock(&mcu_led->lock);
> +
> + if (brightness == LED_OFF) {
> + led_power_cmd[3] = CMD_CHAR(IEI_LED_OFF);
> + mcu_led->led_power_state = LED_OFF;
> + } else {
> + led_power_cmd[3] = CMD_CHAR(IEI_LED_ON);
> + mcu_led->led_power_state = LED_ON;
> + }
> +
> + mutex_unlock(&mcu_led->lock);
> +
> + ret = iei_wt61p803_puzzle_write_command(mcu_led->mcu, led_power_cmd,
> + sizeof(led_power_cmd), resp_buf, &reply_size);
> +
> + kfree(resp_buf);
> +
> + return ret;
> +}
> +
> +static enum led_brightness
> +iei_wt61p803_puzzle_led_brightness_get(struct led_classdev *cdev)
> +{
> + struct iei_wt61p803_puzzle_led *mcu_led =
> + cdev_to_iei_wt61p803_puzzle_led(cdev);

> +

This is not needed.

> + int led_state;
> +
> + mutex_lock(&mcu_led->lock);
> + led_state = mcu_led->led_power_state;
> + mutex_unlock(&mcu_led->lock);
> +
> + return led_state;
> +}
> +
> +static int iei_wt61p803_puzzle_led_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct iei_wt61p803_puzzle *mcu = dev_get_drvdata(dev->parent);

> + struct device_node *np = dev->of_node;

Drop this.

> +

This is not needed.

> + struct iei_wt61p803_puzzle_led *mcu_led;

> + struct device_node *child;

struct fwnode_handle *child;

> +

This is not needed

> + int ret;
> +
> + mcu_led = devm_kzalloc(dev, sizeof(*mcu_led), GFP_KERNEL);
> + if (!mcu_led)
> + return -ENOMEM;
> +
> + mcu_led->mcu = mcu;
> +
> + /* The default LED power state is 1 */
> + mcu_led->led_power_state = 1;
> +
> + /* Init the mutex lock */
> + mutex_init(&mcu_led->lock);
> +
> + dev_set_drvdata(dev, mcu_led);
> +

> + for_each_child_of_node(np, child) {

device_for_each_child_node()

> + struct led_classdev *led;
> + u32 reg;
> +
> + led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
> + if (!led)
> + return -ENOMEM;
> +

> + ret = of_property_read_u32(child, "reg", &reg);

fwnode_property_read_u32()

> + if (ret || reg > 1) {

> + dev_err(dev, "Could not register 'reg' of %s\n",
> + child->name);

%pfw

> + continue;
> + }
> +

> + if (of_property_read_string(child, "label", &led->name))

of_ -> fwnode_

> + led->name = child->name;

devm_kasprintf()

See, for example, drivers/leds/leds-max77650.c for such approach.

> +
> + of_property_read_string(child, "linux,default-trigger",
> + &led->default_trigger);

of_ -> fwnode_

> +
> + led->brightness_set_blocking =
> + iei_wt61p803_puzzle_led_brightness_set_blocking;
> + led->brightness_get = iei_wt61p803_puzzle_led_brightness_get;
> +
> + led->max_brightness = 1;
> +
> + ret = devm_led_classdev_register(dev, led);
> + if (ret) {
> + dev_err(dev, "Could not register %s\n", led->name);
> + return ret;
> + }
> + }
> +
> + return 0;

> +

This is not needed.

> +}
> +
> +static const struct of_device_id iei_wt61p803_puzzle_led_of_match[] = {
> + { .compatible = "iei,wt61p803-puzzle-leds" },
> + { }
> +};
> +MODULE_DEVICE_TABLE(of, iei_wt61p803_puzzle_led_of_match);
> +
> +static struct platform_driver iei_wt61p803_puzzle_led_driver = {
> + .driver = {
> + .name = "iei-wt61p803-puzzle-led",
> + .of_match_table = iei_wt61p803_puzzle_led_of_match,
> + },
> + .probe = iei_wt61p803_puzzle_led_probe,
> +};
> +module_platform_driver(iei_wt61p803_puzzle_led_driver);
> +
> +MODULE_DESCRIPTION("iEi WT61P803 PUZZLE front panel LED driver");
> +MODULE_AUTHOR("Luka Kovacic <luka.kovacic@sartura.hr>");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("platform:leds-iei-wt61p803-puzzle");
> --
> 2.20.1
>

--
With Best Regards,
Andy Shevchenko