Re: [PATCH 2/3] leds: add PM8058 LEDs driver

[Jacek Anaszewski <j.anaszewski@samsung.com>]

Hi Linus,

Thanks for the patch. Please refer to my comments below.

On 06/29/2016 04:21 PM, Linus Walleij wrote:
> This adds a driver for the six PM8058 LEDs, three ordinary LEDs,
> two "flash" LEDs and one "keypad" LED.
>
> The "keypad" and "flash" LEDs are not really hard-wired to these
> usecases: for example on the APQ8060 Dragonboard, the "keypad"
> LED is instead used to drive an IR LED used for the proximity
> sensor. The "flash" LEDs are just ordinary high-current LED
> drivers.
>
> Cc: linux-arm-msm@vger.kernel.org
> Cc: Andy Gross <andy.gross@linaro.org>
> Cc: Stephen Boyd <sboyd@codeaurora.org>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
> ---
>   drivers/leds/Kconfig       |   8 ++
>   drivers/leds/Makefile      |   1 +
>   drivers/leds/leds-pm8058.c | 194 +++++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 203 insertions(+)
>   create mode 100644 drivers/leds/leds-pm8058.c
>
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 5ae28340a98b..a6731f00641f 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -617,6 +617,14 @@ config LEDS_VERSATILE
>   	  This option enabled support for the LEDs on the ARM Versatile
>   	  and RealView boards. Say Y to enabled these.
>
> +config LEDS_PM8058
> +	tristate "LED Support for the Qualcomm PM8058 PMIC"
> +	depends on MFD_PM8921_CORE
> +	depends on LEDS_CLASS
> +	help
> +	  Choose this option if you want to use the LED drivers in
> +	  the Qualcomm PM8058 PMIC.
> +
>   comment "LED Triggers"
>   source "drivers/leds/trigger/Kconfig"
>
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index cb2013df52d9..9ee31057f468 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -67,6 +67,7 @@ obj-$(CONFIG_LEDS_KTD2692)		+= leds-ktd2692.o
>   obj-$(CONFIG_LEDS_POWERNV)		+= leds-powernv.o
>   obj-$(CONFIG_LEDS_SEAD3)		+= leds-sead3.o
>   obj-$(CONFIG_LEDS_IS31FL32XX)		+= leds-is31fl32xx.o
> +obj-$(CONFIG_LEDS_PM8058)		+= leds-pm8058.o
>
>   # LED SPI Drivers
>   obj-$(CONFIG_LEDS_DAC124S085)		+= leds-dac124s085.o
> diff --git a/drivers/leds/leds-pm8058.c b/drivers/leds/leds-pm8058.c
> new file mode 100644
> index 000000000000..3ab27ec6f2de
> --- /dev/null
> +++ b/drivers/leds/leds-pm8058.c
> @@ -0,0 +1,194 @@
> +/* Copyright (c) 2010, 2011, 2016 The Linux Foundation. All rights reserved.

Please put only opening "/*" in the first line.

> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 and
> + * only version 2 as published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +#include <linux/of.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm.h>
> +#include <linux/regmap.h>
> +#include <linux/slab.h>
> +#include <linux/spinlock.h>
> +#include <linux/leds.h>

Please arrange include directives in the alphabetical order.

> +
> +#define PM8058_LED_TYPE_COMMON	0x00
> +#define PM8058_LED_TYPE_KEYPAD	0x01
> +#define PM8058_LED_TYPE_FLASH	0x02
> +
> +#define PM8058_LED_TYPE_COMMON_MASK	0xf8
> +#define PM8058_LED_TYPE_KEYPAD_MASK	0xf0
> +
> +struct pm8058_led {
> +	struct regmap *map;
> +	unsigned int reg;
> +	u32 ledtype;
> +	struct led_classdev cdev;
> +};
> +
> +static void pm8058_led_set(struct led_classdev *cled,
> +	enum led_brightness value)
> +{
> +	struct pm8058_led *led;
> +	int ret = 0;
> +
> +	led = container_of(cled, struct pm8058_led, cdev);
> +	switch (led->ledtype) {
> +	case PM8058_LED_TYPE_COMMON:
> +		ret = regmap_update_bits(led->map, led->reg,
> +					 PM8058_LED_TYPE_COMMON_MASK,
> +					 value << 3);

Add a macro definition for 3.

> +		break;
> +	case PM8058_LED_TYPE_KEYPAD:
> +	case PM8058_LED_TYPE_FLASH:
> +		ret = regmap_update_bits(led->map, led->reg,
> +					 PM8058_LED_TYPE_KEYPAD_MASK,
> +					 value << 4);

Add a macro definition for 4.

> +		break;
> +	default:
> +		break;
> +	}
> +	if (ret)
> +		pr_err("Failed to set LED brightness\n");
> +}
> +
> +static enum led_brightness pm8058_led_get(struct led_classdev *cled)
> +{
> +	struct pm8058_led *led;
> +	int ret;
> +	u32 val;
> +
> +	led = container_of(cled, struct pm8058_led, cdev);
> +	switch (led->ledtype) {
> +	case PM8058_LED_TYPE_COMMON:
> +		ret = regmap_read(led->map, led->reg, &val);
> +		if (ret) {
> +			pr_err("Failed to get LED brightness\n");
> +			return LED_OFF;
> +		}
> +		return ((val & 0xf8) >> 3);

Use PM8058_LED_TYPE_COMMON_MASK instead of 0xf8.

> +		break;

This break is redundant.

> +	case PM8058_LED_TYPE_KEYPAD:
> +	case PM8058_LED_TYPE_FLASH:
> +		ret = regmap_read(led->map, led->reg, &val);
> +		if (ret) {
> +			pr_err("Failed to get LED brightness\n");
> +			return LED_OFF;
> +		}
> +		return ((val & 0xf0) >> 4);

Use PM8058_LED_TYPE_KEYPAD_MASK instead of 0xf0.

> +		break;


This break is redundant.

> +	default:
> +		break;
> +	}
> +
> +	return LED_OFF;
> +}
> +
> +static const struct of_device_id pm8058_leds_id_table[] = {
> +	{
> +		.compatible = "qcom,pm8058-led",
> +		.data = (void *)PM8058_LED_TYPE_COMMON
> +	},
> +	{
> +		.compatible = "qcom,pm8058-keypad-led",
> +		.data = (void *)PM8058_LED_TYPE_KEYPAD
> +	},
> +	{
> +		.compatible = "qcom,pm8058-flash-led",
> +		.data = (void *)PM8058_LED_TYPE_FLASH
> +	},

Please add terminating {} entry.

> +};
> +MODULE_DEVICE_TABLE(of, pm8058_leds_id_table);
> +
> +static int pm8058_led_probe(struct platform_device *pdev)
> +{
> +	struct pm8058_led *led;
> +	struct device_node *np = pdev->dev.of_node;
> +	int ret;
> +	struct regmap *map;
> +	const struct of_device_id *match;
> +	const char *state;
> +
> +	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
> +	if (led == NULL)
> +		return -ENOMEM;
> +
> +	match = of_match_node(pm8058_leds_id_table, np);
> +	if (!match)
> +		return -ENXIO;
> +	led->ledtype = (u32)match->data;
> +
> +	map = dev_get_regmap(pdev->dev.parent, NULL);
> +	if (!map) {
> +		dev_err(&pdev->dev, "Parent regmap unavailable.\n");
> +		return -ENXIO;
> +	}
> +	led->map = map;
> +
> +	ret = of_property_read_u32(np, "reg", &led->reg);
> +	if (ret) {
> +		dev_err(&pdev->dev, "no register offset specified\n");
> +		return -EINVAL;
> +	}
> +
> +	/* Use label else node name */
> +	led->cdev.name = of_get_property(np, "label", NULL) ? : np->name;
> +	led->cdev.default_trigger =
> +		of_get_property(np, "linux,default-trigger", NULL);
> +	led->cdev.brightness_set = pm8058_led_set;
> +	led->cdev.brightness_get = pm8058_led_get;
> +	led->cdev.max_brightness = 15;
> +
> +	state = of_get_property(np, "default-state", NULL);
> +	if (state) {
> +		if (!strcmp(state, "keep")) {
> +			led->cdev.brightness = pm8058_led_get(&led->cdev);
> +		} else if (!strcmp(state, "on")) {
> +			led->cdev.brightness = LED_FULL;
> +			pm8058_led_set(&led->cdev, LED_FULL);
> +		} else {
> +			led->cdev.brightness = LED_OFF;
> +			pm8058_led_set(&led->cdev, LED_OFF);
> +		}
> +	}
> +	led->cdev.flags	= LED_CORE_SUSPENDRESUME;
> +
> +	ret = led_classdev_register(&pdev->dev, &led->cdev);

Use devm prefixed version.

> +	if (ret) {
> +		dev_err(&pdev->dev, "unable to register led \"%s\"\n",
> +			led->cdev.name);
> +		return ret;
> +	}
> +	platform_set_drvdata(pdev, led);

And this call will not be needed then.

> +
> +	return 0;
> +}
> +
> +static int __exit pm8058_led_remove(struct platform_device *pdev)
> +{
> +	struct pm8058_led *led = platform_get_drvdata(pdev);
> +
> +	led_classdev_unregister(&led->cdev);
> +	return 0;
> +}

As well as the remove op.

> +
> +static struct platform_driver pm8058_led_driver = {
> +	.probe		= pm8058_led_probe,
> +	.remove		= __exit_p(pm8058_led_remove),
> +	.driver		= {
> +		.name	= "pm8058-leds",
> +		.of_match_table = pm8058_leds_id_table,
> +	},
> +};
> +module_platform_driver(pm8058_led_driver);
> +
> +MODULE_DESCRIPTION("PM8058 LEDs driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("platform:pm8058-leds");
>


-- 
Best regards,
Jacek Anaszewski