[PATCH v6 7/7] leds: max77705: Add LEDs support

[Dzmitry Sankouski <dsankouski@gmail.com>]

This adds basic support for LEDs for the max77705 PMIC.

Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>

---
Changes for v5:
- use same hardware name in Kconfig and module descriptions
- remove copyrighter owner from module authors

Changes in v4:
- inline BLINK_(ON|OFF) macro
- remove camel case
- drop backwards compatibility(new driver)
- drop module alias
---
 MAINTAINERS                  |   1 +
 drivers/leds/Kconfig         |   6 ++++++
 drivers/leds/Makefile        |   1 +
 drivers/leds/leds-max77705.c | 157 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 165 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 4bc9c0da6adb..66a1dd7577c4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -14079,6 +14079,7 @@ F:	drivers/*/max14577*.c
 F:	drivers/*/max77686*.c
 F:	drivers/*/max77693*.c
 F:	drivers/*/max77705*.c
+F:	drivers/leds/leds-max77705.c
 F:	drivers/clk/clk-max77686.c
 F:	drivers/extcon/extcon-max14577.c
 F:	drivers/extcon/extcon-max77693.c
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index b784bb74a837..a8492623caa4 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -753,6 +753,12 @@ config LEDS_MAX77650
 	help
 	  LEDs driver for MAX77650 family of PMICs from Maxim Integrated.
 
+config LEDS_MAX77705
+	tristate "LED support for Maxim MAX77705 PMIC"
+	depends on MFD_MAX77705 && LEDS_CLASS && I2C
+	help
+	  LED driver for MAX77705 MFD chip from Maxim Integrated.
+
 config LEDS_MAX8997
 	tristate "LED support for MAX8997 PMIC"
 	depends on LEDS_CLASS && MFD_MAX8997
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 18afbb5a23ee..096bf244527d 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -60,6 +60,7 @@ 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-$(CONFIG_LEDS_MAX77705)		+= leds-max77705.o
 obj-$(CONFIG_LEDS_MAX8997)		+= leds-max8997.o
 obj-$(CONFIG_LEDS_MC13783)		+= leds-mc13783.o
 obj-$(CONFIG_LEDS_MENF21BMC)		+= leds-menf21bmc.o
diff --git a/drivers/leds/leds-max77705.c b/drivers/leds/leds-max77705.c
new file mode 100644
index 000000000000..50af81fb7324
--- /dev/null
+++ b/drivers/leds/leds-max77705.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Based on leds-max77650 driver:
+//		Copyright (C) 2018 BayLibre SAS
+//		Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+//
+// LED driver for MAXIM 77705 MFD.
+// Copyright (C) 2024 Dzmitry Sankouski <dsankouski@gmail.org>
+
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/mfd/max77705-private.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define MAX77705_LED_NUM_LEDS		4
+#define MAX77705_LED_EN_MASK		GENMASK(1, 0)
+#define MAX77705_LED_MAX_BRIGHTNESS	0xff
+
+struct max77705_led {
+	struct led_classdev cdev;
+	struct regmap *regmap;
+	unsigned int en_shift;
+	unsigned int reg_brightness;
+};
+
+static struct max77705_led *max77705_to_led(struct led_classdev *cdev)
+{
+	return container_of(cdev, struct max77705_led, cdev);
+}
+
+static int max77705_rgb_blink(struct led_classdev *cdev,
+				unsigned long *delay_on,
+				unsigned long *delay_off)
+{
+	struct max77705_led *led = max77705_to_led(cdev);
+	int value, on_value, off_value;
+
+	on_value = (((*delay_on < 100) ? 0 :
+			(*delay_on < 500) ? *delay_on/100 - 1 :
+			(*delay_on < 3250) ? (*delay_on - 500) / 250 + 4 : 15) << 4);
+	off_value = ((*delay_off < 1) ? 0x00 :
+			(*delay_off < 500) ? 0x01 :
+			(*delay_off < 5000) ? *delay_off / 500 :
+			(*delay_off < 8000) ? (*delay_off - 5000) / 1000 + 10 :
+			(*delay_off < 12000) ? (*delay_off - 8000) / 2000 + 13 : 15);
+	value = on_value | off_value;
+	return regmap_write(led->regmap, MAX77705_RGBLED_REG_LEDBLNK, value);
+}
+
+static int max77705_led_brightness_set(struct led_classdev *cdev,
+					enum led_brightness brightness)
+{
+	struct max77705_led *led = max77705_to_led(cdev);
+	int ret;
+	unsigned long blink_default = 0;
+
+	if (brightness == LED_OFF) {
+		// Flash OFF
+		ret = regmap_update_bits(led->regmap,
+					MAX77705_RGBLED_REG_LEDEN,
+					MAX77705_LED_EN_MASK << led->en_shift, 0);
+		max77705_rgb_blink(cdev, &blink_default, &blink_default);
+	} else {
+		// Set current
+		ret = regmap_write(led->regmap,
+				   led->reg_brightness, brightness);
+		if (ret < 0)
+			return ret;
+
+		ret = regmap_update_bits(led->regmap,
+					MAX77705_RGBLED_REG_LEDEN, LED_ON << led->en_shift,
+					MAX77705_LED_EN_MASK << led->en_shift);
+	}
+
+	return ret;
+}
+
+static int max77705_led_probe(struct platform_device *pdev)
+{
+	struct fwnode_handle *child;
+	struct max77705_led *leds, *led;
+	struct device *dev;
+	struct regmap *map;
+	int rv, num_leds;
+	u32 reg;
+
+	dev = &pdev->dev;
+
+	leds = devm_kcalloc(dev, sizeof(*leds),
+				MAX77705_LED_NUM_LEDS, GFP_KERNEL);
+	if (!leds)
+		return -ENOMEM;
+
+	map = dev_get_regmap(dev->parent, NULL);
+	if (!map)
+		return -ENODEV;
+
+	num_leds = device_get_child_node_count(dev);
+	if (!num_leds || num_leds > MAX77705_LED_NUM_LEDS)
+		return -ENODEV;
+
+	device_for_each_child_node(dev, child) {
+		struct led_init_data init_data = {};
+
+		rv = fwnode_property_read_u32(child, "reg", &reg);
+		if (rv || reg >= MAX77705_LED_NUM_LEDS) {
+			rv = -EINVAL;
+			goto err_node_put;
+		}
+
+		led = &leds[reg];
+		led->regmap = map;
+		led->reg_brightness = MAX77705_RGBLED_REG_LED0BRT + reg;
+		led->en_shift = 2 * reg;
+		led->cdev.brightness_set_blocking = max77705_led_brightness_set;
+		led->cdev.blink_set = max77705_rgb_blink;
+		led->cdev.max_brightness = MAX77705_LED_MAX_BRIGHTNESS;
+
+		init_data.fwnode = child;
+		init_data.devicename = "max77705";
+
+		rv = devm_led_classdev_register_ext(dev, &led->cdev,
+							&init_data);
+		if (rv)
+			goto err_node_put;
+
+		rv = max77705_led_brightness_set(&led->cdev, LED_OFF);
+		if (rv)
+			goto err_node_put;
+	}
+
+	return 0;
+err_node_put:
+	fwnode_handle_put(child);
+	return rv;
+}
+
+static const struct of_device_id max77705_led_of_match[] = {
+	{ .compatible = "maxim,max77705-led" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, max77705_led_of_match);
+
+static struct platform_driver max77705_led_driver = {
+	.driver = {
+		.name = "max77705-led",
+		.of_match_table = max77705_led_of_match,
+	},
+	.probe = max77705_led_probe,
+};
+module_platform_driver(max77705_led_driver);
+
+MODULE_DESCRIPTION("Maxim MAX77705 LED driver");
+MODULE_AUTHOR("Dzmitry Sankouski <dsankouski@gmail.com>");
+MODULE_LICENSE("GPL");

-- 
2.39.2