[PATCH v3] leds: max5970: Add support for max5970

From: Naresh Solanki
Date: Thu Aug 24 2023 - 07:14:52 EST


From: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>

The MAX5970 is hot swap controller and has 4 indication LED.

Signed-off-by: Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>
Signed-off-by: Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>
---
Changes in V3:
- Drop array for ddata variable.
Changes in V2:
- Add of_node_put before return.
- Code cleanup
- Refactor code & remove max5970_setup_led function.
---
drivers/leds/Kconfig | 11 ++++
drivers/leds/Makefile | 1 +
drivers/leds/leds-max5970.c | 110 ++++++++++++++++++++++++++++++++++++
3 files changed, 122 insertions(+)
create mode 100644 drivers/leds/leds-max5970.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index b92208eccdea..03ef527cc545 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -637,6 +637,17 @@ config LEDS_ADP5520
To compile this driver as a module, choose M here: the module will
be called leds-adp5520.

+config LEDS_MAX5970
+ tristate "LED Support for Maxim 5970"
+ depends on LEDS_CLASS
+ depends on MFD_MAX5970
+ 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-max5970.
+
config LEDS_MC13783
tristate "LED Support for MC13XXX PMIC"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index d7348e8bc019..6eaee0a753c6 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -56,6 +56,7 @@ 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-$(CONFIG_LEDS_MAX5970) += leds-max5970.o
obj-$(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-max5970.c b/drivers/leds/leds-max5970.c
new file mode 100644
index 000000000000..c9685990e26e
--- /dev/null
+++ b/drivers/leds/leds-max5970.c
@@ -0,0 +1,110 @@
+// 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/max5970.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define ldev_to_maxled(c) container_of(c, struct max5970_led, cdev)
+
+struct max5970_led {
+ struct device *dev;
+ struct regmap *regmap;
+ struct led_classdev cdev;
+ unsigned int index;
+};
+
+static int max5970_led_set_brightness(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ struct max5970_led *ddata = ldev_to_maxled(cdev);
+ int ret, val;
+
+ /* 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 max5970_led_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct device_node *np = dev_of_node(dev->parent);
+ struct regmap *regmap;
+ struct device_node *led_node;
+ struct device_node *child;
+ struct max5970_led *ddata;
+ int ret = -ENODEV, num_leds = 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", &reg))
+ continue;
+
+ if (reg >= MAX5970_NUM_LEDS) {
+ dev_err(dev, "invalid LED (%u >= %d)\n", reg, MAX5970_NUM_LEDS);
+ continue;
+ }
+
+ ddata = devm_kzalloc(dev, sizeof(struct max5970_led), GFP_KERNEL);
+ if (!ddata) {
+ of_node_put(child);
+ return -ENOMEM;
+ }
+
+ ddata->index = reg;
+ ddata->regmap = regmap;
+ ddata->dev = dev;
+
+ if (of_property_read_string(child, "label", &ddata->cdev.name))
+ ddata->cdev.name = child->name;
+
+ ddata->cdev.max_brightness = 1;
+ ddata->cdev.brightness_set_blocking = max5970_led_set_brightness;
+ ddata->cdev.default_trigger = "none";
+
+ ret = devm_led_classdev_register(ddata->dev, &ddata->cdev);
+ if (ret < 0) {
+ of_node_put(child);
+ dev_err(dev, "Failed to initialize LED %u\n", reg);
+ return ret;
+ }
+ num_leds++;
+ }
+
+ return ret;
+}
+
+static struct platform_driver max5970_led_driver = {
+ .driver = {
+ .name = "max5970-led",
+ },
+ .probe = max5970_led_probe,
+};
+
+module_platform_driver(max5970_led_driver);
+MODULE_AUTHOR("Patrick Rudolph <patrick.rudolph@xxxxxxxxxxxxx>");
+MODULE_AUTHOR("Naresh Solanki <Naresh.Solanki@xxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("MAX5970_hot-swap controller LED driver");
+MODULE_LICENSE("GPL");

base-commit: baca986e1f2c31f8e4b2a6d99d47c3bc844033e8
--
2.41.0