leds: max77650: Add LEDs support

[linux-2.6-microblaze.git] / drivers / leds / leds-max77650.c

diff --git a/drivers/leds/leds-max77650.c b/drivers/leds/leds-max77650.c
new file mode 100644 (file)
index 0000000..6b74ce9
--- /dev/null
+++ b/drivers/leds/leds-max77650.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Copyright (C) 2018 BayLibre SAS
+// Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+//
+// LED driver for MAXIM 77650/77651 charger/power-supply.
+
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/mfd/max77650.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#define MAX77650_LED_NUM_LEDS          3
+
+#define MAX77650_LED_A_BASE            0x40
+#define MAX77650_LED_B_BASE            0x43
+
+#define MAX77650_LED_BR_MASK           GENMASK(4, 0)
+#define MAX77650_LED_EN_MASK           GENMASK(7, 6)
+
+#define MAX77650_LED_MAX_BRIGHTNESS    MAX77650_LED_BR_MASK
+
+/* Enable EN_LED_MSTR. */
+#define MAX77650_LED_TOP_DEFAULT       BIT(0)
+
+#define MAX77650_LED_ENABLE            GENMASK(7, 6)
+#define MAX77650_LED_DISABLE           0x00
+
+#define MAX77650_LED_A_DEFAULT         MAX77650_LED_DISABLE
+/* 100% on duty */
+#define MAX77650_LED_B_DEFAULT         GENMASK(3, 0)
+
+struct max77650_led {
+       struct led_classdev cdev;
+       struct regmap *map;
+       unsigned int regA;
+       unsigned int regB;
+};
+
+static struct max77650_led *max77650_to_led(struct led_classdev *cdev)
+{
+       return container_of(cdev, struct max77650_led, cdev);
+}
+
+static int max77650_led_brightness_set(struct led_classdev *cdev,
+                                      enum led_brightness brightness)
+{
+       struct max77650_led *led = max77650_to_led(cdev);
+       int val, mask;
+
+       mask = MAX77650_LED_BR_MASK | MAX77650_LED_EN_MASK;
+
+       if (brightness == LED_OFF)
+               val = MAX77650_LED_DISABLE;
+       else
+               val = MAX77650_LED_ENABLE | brightness;
+
+       return regmap_update_bits(led->map, led->regA, mask, val);
+}
+
+static int max77650_led_probe(struct platform_device *pdev)
+{
+       struct device_node *of_node, *child;
+       struct max77650_led *leds, *led;
+       struct device *parent;
+       struct device *dev;
+       struct regmap *map;
+       const char *label;
+       int rv, num_leds;
+       u32 reg;
+
+       dev = &pdev->dev;
+       parent = dev->parent;
+       of_node = dev->of_node;
+
+       if (!of_node)
+               return -ENODEV;
+
+       leds = devm_kcalloc(dev, sizeof(*leds),
+                           MAX77650_LED_NUM_LEDS, GFP_KERNEL);
+       if (!leds)
+               return -ENOMEM;
+
+       map = dev_get_regmap(dev->parent, NULL);
+       if (!map)
+               return -ENODEV;
+
+       num_leds = of_get_child_count(of_node);
+       if (!num_leds || num_leds > MAX77650_LED_NUM_LEDS)
+               return -ENODEV;
+
+       for_each_child_of_node(of_node, child) {
+               rv = of_property_read_u32(child, "reg", &reg);
+               if (rv || reg >= MAX77650_LED_NUM_LEDS)
+                       return -EINVAL;
+
+               led = &leds[reg];
+               led->map = map;
+               led->regA = MAX77650_LED_A_BASE + reg;
+               led->regB = MAX77650_LED_B_BASE + reg;
+               led->cdev.brightness_set_blocking = max77650_led_brightness_set;
+               led->cdev.max_brightness = MAX77650_LED_MAX_BRIGHTNESS;
+
+               label = of_get_property(child, "label", NULL);
+               if (!label) {
+                       led->cdev.name = "max77650::";
+               } else {
+                       led->cdev.name = devm_kasprintf(dev, GFP_KERNEL,
+                                                       "max77650:%s", label);
+                       if (!led->cdev.name)
+                               return -ENOMEM;
+               }
+
+               of_property_read_string(child, "linux,default-trigger",
+                                       &led->cdev.default_trigger);
+
+               rv = devm_of_led_classdev_register(dev, child, &led->cdev);
+               if (rv)
+                       return rv;
+
+               rv = regmap_write(map, led->regA, MAX77650_LED_A_DEFAULT);
+               if (rv)
+                       return rv;
+
+               rv = regmap_write(map, led->regB, MAX77650_LED_B_DEFAULT);
+               if (rv)
+                       return rv;
+       }
+
+       return regmap_write(map,
+                           MAX77650_REG_CNFG_LED_TOP,
+                           MAX77650_LED_TOP_DEFAULT);
+}
+
+static struct platform_driver max77650_led_driver = {
+       .driver = {
+               .name = "max77650-led",
+       },
+       .probe = max77650_led_probe,
+};
+module_platform_driver(max77650_led_driver);
+
+MODULE_DESCRIPTION("MAXIM 77650/77651 LED driver");
+MODULE_AUTHOR("Bartosz Golaszewski <bgolaszewski@baylibre.com>");
+MODULE_LICENSE("GPL v2");