From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx> max597x is hot swap controller with indicator LED support. This driver uses DT property to configure led during boot time & also provide the LED control in sysfs. DTS example: i2c { #address-cells = <1>; #size-cells = <0>; regulator@3a { compatible = "maxim,max5978"; reg = <0x3a>; vss1-supply = <&p3v3>; regulators { sw0_ref_0: sw0 { shunt-resistor-micro-ohms = <12000>; }; }; leds { #address-cells = <1>; #size-cells = <0>; led@0 { reg = <0>; label = "ssd0:green"; default-state = "on"; }; led@1 { reg = <1>; label = "ssd1:green"; default-state = "on"; }; }; }; }; Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx> Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx> ... Changes in V5: - Update commit message - Fix comments - Add necessary new line Changes in V4: - Remove unwanted preinitialise - Remove unneeded line breaks - Fix variable name to avoid confusion - Update module description to mention LED driver. Changes in V3: - Remove of_node_put as its handled by for loop - Print error if an LED fails to register. - Update driver name in Kconfig description - Remove unneeded variable assignment - Use devm_led_classdev_register to reget led Changes in V2: - Fix regmap update - Remove devm_kfree - Remove default-state - Add example dts in commit message - Fix whitespace in Kconfig - Fix comment --- drivers/leds/Kconfig | 11 ++++ drivers/leds/Makefile | 1 + drivers/leds/leds-max597x.c | 115 ++++++++++++++++++++++++++++++++++++ 3 files changed, 127 insertions(+) create mode 100644 drivers/leds/leds-max597x.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 9dbce09eabac..60004cb8c257 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -590,6 +590,17 @@ config LEDS_ADP5520 To compile this driver as a module, choose M here: the module will be called leds-adp5520. +config LEDS_MAX597X + tristate "LED Support for Maxim 597x" + depends on LEDS_CLASS + depends on MFD_MAX597X + help + This option enables support for the Maxim MAX5970 & MAX5978 smart + switch indication LEDs via the I2C bus. + + To compile this driver as a module, choose M here: the module will + be called leds-max597x. + config LEDS_MC13783 tristate "LED Support for MC13XXX PMIC" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index d30395d11fd8..da1192e40268 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -53,6 +53,7 @@ obj-$(CONFIG_LEDS_LP8501) += leds-lp8501.o obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o +obj-$(CONFIG_LEDS_MAX597X) += leds-max597x.o obj-$(CONFIG_LEDS_MAX77650) += leds-max77650.o obj-$(CONFIG_LEDS_MAX8997) += leds-max8997.o obj-$(CONFIG_LEDS_MC13783) += leds-mc13783.o diff --git a/drivers/leds/leds-max597x.c b/drivers/leds/leds-max597x.c new file mode 100644 index 000000000000..edbd43018822 --- /dev/null +++ b/drivers/leds/leds-max597x.c @@ -0,0 +1,115 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Device driver for leds in MAX5970 and MAX5978 IC + * + * Copyright (c) 2022 9elements GmbH + * + * Author: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx> + */ + +#include <linux/leds.h> +#include <linux/mfd/max597x.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +#define ldev_to_maxled(c) container_of(c, struct max597x_led, cdev) + +struct max597x_led { + struct regmap *regmap; + struct led_classdev cdev; + unsigned int index; +}; + +static int max597x_led_set_brightness(struct led_classdev *cdev, + enum led_brightness brightness) +{ + struct max597x_led *ddata = ldev_to_maxled(cdev); + int ret, val; + + if (!ddata->regmap) + return -ENODEV; + + /* Set/clear corresponding bit for given led index */ + val = !brightness ? BIT(ddata->index) : 0; + + ret = regmap_update_bits(ddata->regmap, MAX5970_REG_LED_FLASH, BIT(ddata->index), val); + if (ret < 0) + dev_err(cdev->dev, "failed to set brightness %d", ret); + + return ret; +} + +static int max597x_setup_led(struct device *dev, struct regmap *regmap, struct device_node *nc, + u32 reg) +{ + struct max597x_led *ddata; + int ret; + + ddata = devm_kzalloc(dev, sizeof(struct max597x_led), GFP_KERNEL); + if (!ddata) + return -ENOMEM; + + if (of_property_read_string(nc, "label", &ddata->cdev.name)) + ddata->cdev.name = nc->name; + + ddata->cdev.max_brightness = 1; + ddata->cdev.brightness_set_blocking = max597x_led_set_brightness; + ddata->cdev.default_trigger = "none"; + ddata->index = reg; + ddata->regmap = regmap; + + ret = devm_led_classdev_register(dev, &ddata->cdev); + if (ret) + dev_err(dev, "Error initializing LED %s", ddata->cdev.name); + + return ret; +} + +static int max597x_led_probe(struct platform_device *pdev) +{ + struct device_node *np = dev_of_node(pdev->dev.parent); + struct regmap *regmap; + struct device_node *led_node; + struct device_node *child; + int ret = 0; + + regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!regmap) + return -EPROBE_DEFER; + + led_node = of_get_child_by_name(np, "leds"); + if (!led_node) + return -ENODEV; + + for_each_available_child_of_node(led_node, child) { + u32 reg; + + if (of_property_read_u32(child, "reg", ®)) + continue; + + if (reg >= MAX597X_NUM_LEDS) { + dev_err(&pdev->dev, "invalid LED (%u >= %d)\n", reg, + MAX597X_NUM_LEDS); + continue; + } + + ret = max597x_setup_led(&pdev->dev, regmap, child, reg); + if (ret < 0) + dev_err(&pdev->dev, "Failed to initialize LED %u\n", reg); + } + + return ret; +} + +static struct platform_driver max597x_led_driver = { + .driver = { + .name = "max597x-led", + }, + .probe = max597x_led_probe, +}; + +module_platform_driver(max597x_led_driver); +MODULE_AUTHOR("Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("MAX5970_hot-swap controller LED driver"); +MODULE_LICENSE("GPL"); base-commit: 9d8d0d98885abba451d7ffc4885236d14ead3c9a -- 2.39.1