Re: [PATCH 2/2 v4] leds: add PM8058 LEDs driver

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Tue 16 Aug 02:25 PDT 2016, 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>

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> ---
> ChangeLog v3->v4:
> - Remove unneeded #includes
> - Move mask/val outside the switch statement, set up the masking
>   and shifting in the switch and have a single regmap call after
>   the switch in led_set() and led_get()
> - Use of_device_get__match_data() and move match table to the
>   bottom of the file.
> - Handle the 5 vs 4 bit resolution difference in max brightness
>   when registering the different LED types.
> - Pass the max brightness for the LED if set to "on" instead of
>   hammering with LED_FULL.
> - Set core suspend only for the keypad and flash LEDs.
> ChangeLog v2->v3:
> - No changes, just resending.
> ChangeLog v1->v2:
> - Arrange #includes in alphabetical order
> - Use #define'd mask and shift and abstain from magic values
> - Drop surplus break; statements in switch clause
> - Put in the missed terminator {} in the OF match table
> - Use the devm_led_classdev_register() call to get managed resources
> - As a result drop the whole redundant .remove() clause
> ---
>  drivers/leds/Kconfig       |   8 ++
>  drivers/leds/Makefile      |   1 +
>  drivers/leds/leds-pm8058.c | 191 +++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 200 insertions(+)
>  create mode 100644 drivers/leds/leds-pm8058.c
> 
> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 9dcc9b13d495..f499db5a8552 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -631,6 +631,14 @@ 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 0684c865a1c0..220860c970ca 100644
> --- a/drivers/leds/Makefile
> +++ b/drivers/leds/Makefile
> @@ -68,6 +68,7 @@ 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..a52674327857
> --- /dev/null
> +++ b/drivers/leds/leds-pm8058.c
> @@ -0,0 +1,191 @@
> +/* Copyright (c) 2010, 2011, 2016 The Linux Foundation. All rights reserved.
> + *
> + * 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/leds.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm.h>
> +#include <linux/regmap.h>
> +
> +#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
> +#define PM8058_LED_TYPE_COMMON_SHIFT	3
> +#define PM8058_LED_TYPE_KEYPAD_SHIFT	4
> +
> +struct pm8058_led {
> +	struct regmap *map;
> +	u32 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;
> +	unsigned int mask = 0;
> +	unsigned int val = 0;
> +
> +	led = container_of(cled, struct pm8058_led, cdev);
> +	switch (led->ledtype) {
> +	case PM8058_LED_TYPE_COMMON:
> +		mask = PM8058_LED_TYPE_COMMON_MASK;
> +		val = value << PM8058_LED_TYPE_COMMON_SHIFT;
> +		break;
> +	case PM8058_LED_TYPE_KEYPAD:
> +	case PM8058_LED_TYPE_FLASH:
> +		mask = PM8058_LED_TYPE_KEYPAD_MASK;
> +		val = value << PM8058_LED_TYPE_KEYPAD_SHIFT;
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	ret = regmap_update_bits(led->map, led->reg, mask, val);
> +	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;
> +	unsigned int val;
> +
> +	led = container_of(cled, struct pm8058_led, cdev);
> +
> +	ret = regmap_read(led->map, led->reg, &val);
> +	if (ret) {
> +		pr_err("Failed to get LED brightness\n");
> +		return LED_OFF;
> +	}
> +
> +	switch (led->ledtype) {
> +	case PM8058_LED_TYPE_COMMON:
> +		val &= PM8058_LED_TYPE_COMMON_MASK;
> +		val >>= PM8058_LED_TYPE_COMMON_SHIFT;
> +		break;
> +	case PM8058_LED_TYPE_KEYPAD:
> +	case PM8058_LED_TYPE_FLASH:
> +		val &= PM8058_LED_TYPE_KEYPAD_MASK;
> +		val >>= PM8058_LED_TYPE_KEYPAD_SHIFT;
> +		break;
> +	default:
> +		val = LED_OFF;
> +		break;
> +	}
> +
> +	return val;
> +}
> +
> +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 char *state;
> +	enum led_brightness maxbright;
> +
> +	led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
> +	if (!led)
> +		return -ENOMEM;
> +
> +	led->ledtype = (u32)of_device_get_match_data(&pdev->dev);
> +
> +	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;
> +	if (led->ledtype == PM8058_LED_TYPE_COMMON)
> +		maxbright = 31; /* 5 bits */
> +	else
> +		maxbright = 15; /* 4 bits */
> +	led->cdev.max_brightness = maxbright;
> +
> +	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 = maxbright;
> +			pm8058_led_set(&led->cdev, maxbright);
> +		} else {
> +			led->cdev.brightness = LED_OFF;
> +			pm8058_led_set(&led->cdev, LED_OFF);
> +		}
> +	}
> +
> +	if (led->ledtype == PM8058_LED_TYPE_KEYPAD ||
> +	    led->ledtype == PM8058_LED_TYPE_FLASH)
> +		led->cdev.flags	= LED_CORE_SUSPENDRESUME;
> +
> +	ret = devm_led_classdev_register(&pdev->dev, &led->cdev);
> +	if (ret) {
> +		dev_err(&pdev->dev, "unable to register led \"%s\"\n",
> +			led->cdev.name);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +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
> +	},
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, pm8058_leds_id_table);
> +
> +static struct platform_driver pm8058_led_driver = {
> +	.probe		= pm8058_led_probe,
> +	.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");
> -- 
> 2.7.4
>