leds: Add suuport for MAX8997-LED driver

This patch enables LED controller in MAX8997 PMIC.

Signed-off-by: Donggeun Kim <dg77.kim@samsung.com>
Signed-off-by: MyungJoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 380 insertions, 0 deletions

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index ff203a421863..c0e30e8bdc19 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -387,6 +387,13 @@ config LEDS_RENESAS_TPU
           pin function. The latter to support brightness control.
           Brightness control is supported but hardware blinking is not.
 
+config LEDS_MAX8997
+        tristate "LED support for MAX8997 PMIC"
+        depends on LEDS_CLASS && MFD_MAX8997
+        help
+          This option enables support for on-chip LED drivers on
+          MAXIM MAX8997 PMIC.
+
 config LEDS_TRIGGERS
         bool "LED Trigger support"
         depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index e4f6bf568880..17f1e986e24e 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_LEDS_NS2)			+= leds-ns2.o
 obj-$(CONFIG_LEDS_NETXBIG)              += leds-netxbig.o
 obj-$(CONFIG_LEDS_ASIC3)                += leds-asic3.o
 obj-$(CONFIG_LEDS_RENESAS_TPU)          += leds-renesas-tpu.o
+obj-$(CONFIG_LEDS_MAX8997)              += leds-max8997.o
 
 # LED SPI Drivers
 obj-$(CONFIG_LEDS_DAC124S085)           += leds-dac124s085.o
diff --git a/drivers/leds/leds-max8997.c b/drivers/leds/leds-max8997.c
new file mode 100644
index 000000000000..f4c0e37fad1e
--- /dev/null
+++ b/drivers/leds/leds-max8997.c
@@ -0,0 +1,372 @@
+/*
+ * leds-max8997.c - LED class driver for MAX8997 LEDs.
+ *
+ * Copyright (C) 2011 Samsung Electronics
+ * Donggeun Kim <dg77.kim@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/leds.h>
+#include <linux/mfd/max8997.h>
+#include <linux/mfd/max8997-private.h>
+#include <linux/platform_device.h>
+
+#define MAX8997_LED_FLASH_SHIFT                 3
+#define MAX8997_LED_FLASH_CUR_MASK              0xf8
+#define MAX8997_LED_MOVIE_SHIFT                 4
+#define MAX8997_LED_MOVIE_CUR_MASK              0xf0
+
+#define MAX8997_LED_FLASH_MAX_BRIGHTNESS        0x1f
+#define MAX8997_LED_MOVIE_MAX_BRIGHTNESS        0xf
+#define MAX8997_LED_NONE_MAX_BRIGHTNESS         0
+
+#define MAX8997_LED0_FLASH_MASK                 0x1
+#define MAX8997_LED0_FLASH_PIN_MASK             0x5
+#define MAX8997_LED0_MOVIE_MASK                 0x8
+#define MAX8997_LED0_MOVIE_PIN_MASK             0x28
+
+#define MAX8997_LED1_FLASH_MASK                 0x2
+#define MAX8997_LED1_FLASH_PIN_MASK             0x6
+#define MAX8997_LED1_MOVIE_MASK                 0x10
+#define MAX8997_LED1_MOVIE_PIN_MASK             0x30
+
+#define MAX8997_LED_BOOST_ENABLE_MASK           (1 << 6)
+
+struct max8997_led {
+        struct max8997_dev *iodev;
+        struct led_classdev cdev;
+        bool enabled;
+        int id;
+        enum max8997_led_mode led_mode;
+        struct mutex mutex;
+};
+
+static void max8997_led_clear_mode(struct max8997_led *led,
+                        enum max8997_led_mode mode)
+{
+        struct i2c_client *client = led->iodev->i2c;
+        u8 val = 0, mask = 0;
+        int ret;
+
+        switch (mode) {
+        case MAX8997_FLASH_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
+                break;
+        case MAX8997_MOVIE_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
+                break;
+        case MAX8997_FLASH_PIN_CONTROL_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
+                break;
+        case MAX8997_MOVIE_PIN_CONTROL_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
+                break;
+        default:
+                break;
+        }
+
+        if (mask) {
+                ret = max8997_update_reg(client,
+                                MAX8997_REG_LEN_CNTL, val, mask);
+                if (ret)
+                        dev_err(led->iodev->dev,
+                                "failed to update register(%d)\n", ret);
+        }
+}
+
+static void max8997_led_set_mode(struct max8997_led *led,
+                        enum max8997_led_mode mode)
+{
+        int ret;
+        struct i2c_client *client = led->iodev->i2c;
+        u8 mask = 0;
+
+        /* First, clear the previous mode */
+        max8997_led_clear_mode(led, led->led_mode);
+
+        switch (mode) {
+        case MAX8997_FLASH_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_FLASH_MASK : MAX8997_LED0_FLASH_MASK;
+                led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
+                break;
+        case MAX8997_MOVIE_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_MOVIE_MASK : MAX8997_LED0_MOVIE_MASK;
+                led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
+                break;
+        case MAX8997_FLASH_PIN_CONTROL_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_FLASH_PIN_MASK : MAX8997_LED0_FLASH_PIN_MASK;
+                led->cdev.max_brightness = MAX8997_LED_FLASH_MAX_BRIGHTNESS;
+                break;
+        case MAX8997_MOVIE_PIN_CONTROL_MODE:
+                mask = led->id ?
+                      MAX8997_LED1_MOVIE_PIN_MASK : MAX8997_LED0_MOVIE_PIN_MASK;
+                led->cdev.max_brightness = MAX8997_LED_MOVIE_MAX_BRIGHTNESS;
+                break;
+        default:
+                led->cdev.max_brightness = MAX8997_LED_NONE_MAX_BRIGHTNESS;
+                break;
+        }
+
+        if (mask) {
+                ret = max8997_update_reg(client,
+                                MAX8997_REG_LEN_CNTL, mask, mask);
+                if (ret)
+                        dev_err(led->iodev->dev,
+                                "failed to update register(%d)\n", ret);
+        }
+
+        led->led_mode = mode;
+}
+
+static void max8997_led_enable(struct max8997_led *led, bool enable)
+{
+        int ret;
+        struct i2c_client *client = led->iodev->i2c;
+        u8 val = 0, mask = MAX8997_LED_BOOST_ENABLE_MASK;
+
+        if (led->enabled == enable)
+                return;
+
+        val = enable ? MAX8997_LED_BOOST_ENABLE_MASK : 0;
+
+        ret = max8997_update_reg(client, MAX8997_REG_BOOST_CNTL, val, mask);
+        if (ret)
+                dev_err(led->iodev->dev,
+                        "failed to update register(%d)\n", ret);
+
+        led->enabled = enable;
+}
+
+static void max8997_led_set_current(struct max8997_led *led,
+                                enum led_brightness value)
+{
+        int ret;
+        struct i2c_client *client = led->iodev->i2c;
+        u8 val = 0, mask = 0, reg = 0;
+
+        switch (led->led_mode) {
+        case MAX8997_FLASH_MODE:
+        case MAX8997_FLASH_PIN_CONTROL_MODE:
+                val = value << MAX8997_LED_FLASH_SHIFT;
+                mask = MAX8997_LED_FLASH_CUR_MASK;
+                reg = led->id ? MAX8997_REG_FLASH2_CUR : MAX8997_REG_FLASH1_CUR;
+                break;
+        case MAX8997_MOVIE_MODE:
+        case MAX8997_MOVIE_PIN_CONTROL_MODE:
+                val = value << MAX8997_LED_MOVIE_SHIFT;
+                mask = MAX8997_LED_MOVIE_CUR_MASK;
+                reg = MAX8997_REG_MOVIE_CUR;
+                break;
+        default:
+                break;
+        }
+
+        if (mask) {
+                ret = max8997_update_reg(client, reg, val, mask);
+                if (ret)
+                        dev_err(led->iodev->dev,
+                                "failed to update register(%d)\n", ret);
+        }
+}
+
+static void max8997_led_brightness_set(struct led_classdev *led_cdev,
+                                enum led_brightness value)
+{
+        struct max8997_led *led =
+                        container_of(led_cdev, struct max8997_led, cdev);
+
+        if (value) {
+                max8997_led_set_current(led, value);
+                max8997_led_enable(led, true);
+        } else {
+                max8997_led_set_current(led, value);
+                max8997_led_enable(led, false);
+        }
+}
+
+static ssize_t max8997_led_show_mode(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+        struct led_classdev *led_cdev = dev_get_drvdata(dev);
+        struct max8997_led *led =
+                        container_of(led_cdev, struct max8997_led, cdev);
+        ssize_t ret = 0;
+
+        mutex_lock(&led->mutex);
+
+        switch (led->led_mode) {
+        case MAX8997_FLASH_MODE:
+                ret += sprintf(buf, "FLASH\n");
+                break;
+        case MAX8997_MOVIE_MODE:
+                ret += sprintf(buf, "MOVIE\n");
+                break;
+        case MAX8997_FLASH_PIN_CONTROL_MODE:
+                ret += sprintf(buf, "FLASH_PIN_CONTROL\n");
+                break;
+        case MAX8997_MOVIE_PIN_CONTROL_MODE:
+                ret += sprintf(buf, "MOVIE_PIN_CONTROL\n");
+                break;
+        default:
+                ret += sprintf(buf, "NONE\n");
+                break;
+        }
+
+        mutex_unlock(&led->mutex);
+
+        return ret;
+}
+
+static ssize_t max8997_led_store_mode(struct device *dev,
+                                struct device_attribute *attr,
+                                const char *buf, size_t size)
+{
+        struct led_classdev *led_cdev = dev_get_drvdata(dev);
+        struct max8997_led *led =
+                        container_of(led_cdev, struct max8997_led, cdev);
+        enum max8997_led_mode mode;
+
+        mutex_lock(&led->mutex);
+
+        if (!strncmp(buf, "FLASH_PIN_CONTROL", 17))
+                mode = MAX8997_FLASH_PIN_CONTROL_MODE;
+        else if (!strncmp(buf, "MOVIE_PIN_CONTROL", 17))
+                mode = MAX8997_MOVIE_PIN_CONTROL_MODE;
+        else if (!strncmp(buf, "FLASH", 5))
+                mode = MAX8997_FLASH_MODE;
+        else if (!strncmp(buf, "MOVIE", 5))
+                mode = MAX8997_MOVIE_MODE;
+        else
+                mode = MAX8997_NONE;
+
+        max8997_led_set_mode(led, mode);
+
+        mutex_unlock(&led->mutex);
+
+        return size;
+}
+
+static DEVICE_ATTR(mode, 0644, max8997_led_show_mode, max8997_led_store_mode);
+
+static int __devinit max8997_led_probe(struct platform_device *pdev)
+{
+        struct max8997_dev *iodev = dev_get_drvdata(pdev->dev.parent);
+        struct max8997_platform_data *pdata = dev_get_platdata(iodev->dev);
+        struct max8997_led *led;
+        char name[20];
+        int ret = 0;
+
+        if (pdata == NULL) {
+                dev_err(&pdev->dev, "no platform data\n");
+                return -ENODEV;
+        }
+
+        led = kzalloc(sizeof(*led), GFP_KERNEL);
+        if (led == NULL) {
+                ret = -ENOMEM;
+                goto err_mem;
+        }
+
+        led->id = pdev->id;
+        snprintf(name, sizeof(name), "max8997-led%d", pdev->id);
+
+        led->cdev.name = name;
+        led->cdev.brightness_set = max8997_led_brightness_set;
+        led->cdev.flags |= LED_CORE_SUSPENDRESUME;
+        led->cdev.brightness = 0;
+        led->iodev = iodev;
+
+        /* initialize mode and brightness according to platform_data */
+        if (pdata->led_pdata) {
+                u8 mode = 0, brightness = 0;
+
+                mode = pdata->led_pdata->mode[led->id];
+                brightness = pdata->led_pdata->brightness[led->id];
+
+                max8997_led_set_mode(led, pdata->led_pdata->mode[led->id]);
+
+                if (brightness > led->cdev.max_brightness)
+                        brightness = led->cdev.max_brightness;
+                max8997_led_set_current(led, brightness);
+                led->cdev.brightness = brightness;
+        } else {
+                max8997_led_set_mode(led, MAX8997_NONE);
+                max8997_led_set_current(led, 0);
+        }
+
+        mutex_init(&led->mutex);
+
+        platform_set_drvdata(pdev, led);
+
+        ret = led_classdev_register(&pdev->dev, &led->cdev);
+        if (ret < 0)
+                goto err_led;
+
+        ret = device_create_file(led->cdev.dev, &dev_attr_mode);
+        if (ret != 0) {
+                dev_err(&pdev->dev,
+                        "failed to create file: %d\n", ret);
+                goto err_file;
+        }
+
+        return 0;
+
+err_file:
+        led_classdev_unregister(&led->cdev);
+err_led:
+        kfree(led);
+err_mem:
+        return ret;
+}
+
+static int __devexit max8997_led_remove(struct platform_device *pdev)
+{
+        struct max8997_led *led = platform_get_drvdata(pdev);
+
+        device_remove_file(led->cdev.dev, &dev_attr_mode);
+        led_classdev_unregister(&led->cdev);
+        kfree(led);
+
+        return 0;
+}
+
+static struct platform_driver max8997_led_driver = {
+        .driver = {
+                .name  = "max8997-led",
+                .owner = THIS_MODULE,
+        },
+        .probe  = max8997_led_probe,
+        .remove = __devexit_p(max8997_led_remove),
+};
+
+static int __init max8997_led_init(void)
+{
+        return platform_driver_register(&max8997_led_driver);
+}
+module_init(max8997_led_init);
+
+static void __exit max8997_led_exit(void)
+{
+        platform_driver_unregister(&max8997_led_driver);
+}
+module_exit(max8997_led_exit);
+
+MODULE_AUTHOR("Donggeun Kim <dg77.kim@samsung.com>");
+MODULE_DESCRIPTION("MAX8997 LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:max8997-led");