[PATCH v4] leds: max597x: Add support for max597x
From: Naresh Solanki
Date: Thu Apr 13 2023 - 06:26:33 EST
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 = "led0";
default-state = "on";
};
led@1 {
reg = <1>;
label = "led1";
default-state = "on";
};
};
};
};
Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
...
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 | 112 ++++++++++++++++++++++++++++++++++++
3 files changed, 124 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..8f34bbca7f21
--- /dev/null
+++ b/drivers/leds/leds-max597x.c
@@ -0,0 +1,112 @@
+// 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: 11e572d06c23d61683e20a98bd16f550ef17ac65
prerequisite-patch-id: 456044abe991b2ff3b521d337825432789d71b29
--
2.39.1