1 files changed, 423 insertions, 0 deletions

diff --git a/drivers/video/backlight/lm3533_bl.c b/drivers/video/backlight/lm3533_bl.c
new file mode 100644
index 000000000000..bebeb63607db
--- /dev/null
+++ b/drivers/video/backlight/lm3533_bl.c
@@ -0,0 +1,423 @@
+/*
+ * lm3533-bl.c -- LM3533 Backlight driver
+ *
+ * Copyright (C) 2011-2012 Texas Instruments
+ *
+ * Author: Johan Hovold <jhovold@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under  the terms of the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/backlight.h>
+#include <linux/fb.h>
+#include <linux/slab.h>
+
+#include <linux/mfd/lm3533.h>
+
+
+#define LM3533_HVCTRLBANK_COUNT         2
+#define LM3533_BL_MAX_BRIGHTNESS        255
+
+#define LM3533_REG_CTRLBANK_AB_BCONF    0x1a
+
+
+struct lm3533_bl {
+        struct lm3533 *lm3533;
+        struct lm3533_ctrlbank cb;
+        struct backlight_device *bd;
+        int id;
+};
+
+
+static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl)
+{
+        return bl->id;
+}
+
+static int lm3533_bl_update_status(struct backlight_device *bd)
+{
+        struct lm3533_bl *bl = bl_get_data(bd);
+        int brightness = bd->props.brightness;
+
+        if (bd->props.power != FB_BLANK_UNBLANK)
+                brightness = 0;
+        if (bd->props.fb_blank != FB_BLANK_UNBLANK)
+                brightness = 0;
+
+        return lm3533_ctrlbank_set_brightness(&bl->cb, (u8)brightness);
+}
+
+static int lm3533_bl_get_brightness(struct backlight_device *bd)
+{
+        struct lm3533_bl *bl = bl_get_data(bd);
+        u8 val;
+        int ret;
+
+        ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val);
+        if (ret)
+                return ret;
+
+        return val;
+}
+
+static const struct backlight_ops lm3533_bl_ops = {
+        .get_brightness = lm3533_bl_get_brightness,
+        .update_status  = lm3533_bl_update_status,
+};
+
+static ssize_t show_id(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+
+        return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id);
+}
+
+static ssize_t show_als_channel(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        unsigned channel = lm3533_bl_get_ctrlbank_id(bl);
+
+        return scnprintf(buf, PAGE_SIZE, "%u\n", channel);
+}
+
+static ssize_t show_als_en(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
+        u8 val;
+        u8 mask;
+        bool enable;
+        int ret;
+
+        ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
+        if (ret)
+                return ret;
+
+        mask = 1 << (2 * ctrlbank);
+        enable = val & mask;
+
+        return scnprintf(buf, PAGE_SIZE, "%d\n", enable);
+}
+
+static ssize_t store_als_en(struct device *dev,
+                                        struct device_attribute *attr,
+                                        const char *buf, size_t len)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
+        int enable;
+        u8 val;
+        u8 mask;
+        int ret;
+
+        if (kstrtoint(buf, 0, &enable))
+                return -EINVAL;
+
+        mask = 1 << (2 * ctrlbank);
+
+        if (enable)
+                val = mask;
+        else
+                val = 0;
+
+        ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
+                                                                        mask);
+        if (ret)
+                return ret;
+
+        return len;
+}
+
+static ssize_t show_linear(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        u8 val;
+        u8 mask;
+        int linear;
+        int ret;
+
+        ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
+        if (ret)
+                return ret;
+
+        mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
+
+        if (val & mask)
+                linear = 1;
+        else
+                linear = 0;
+
+        return scnprintf(buf, PAGE_SIZE, "%x\n", linear);
+}
+
+static ssize_t store_linear(struct device *dev,
+                                        struct device_attribute *attr,
+                                        const char *buf, size_t len)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        unsigned long linear;
+        u8 mask;
+        u8 val;
+        int ret;
+
+        if (kstrtoul(buf, 0, &linear))
+                return -EINVAL;
+
+        mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);
+
+        if (linear)
+                val = mask;
+        else
+                val = 0;
+
+        ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
+                                                                        mask);
+        if (ret)
+                return ret;
+
+        return len;
+}
+
+static ssize_t show_pwm(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        u8 val;
+        int ret;
+
+        ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val);
+        if (ret)
+                return ret;
+
+        return scnprintf(buf, PAGE_SIZE, "%u\n", val);
+}
+
+static ssize_t store_pwm(struct device *dev,
+                                        struct device_attribute *attr,
+                                        const char *buf, size_t len)
+{
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        u8 val;
+        int ret;
+
+        if (kstrtou8(buf, 0, &val))
+                return -EINVAL;
+
+        ret = lm3533_ctrlbank_set_pwm(&bl->cb, val);
+        if (ret)
+                return ret;
+
+        return len;
+}
+
+static LM3533_ATTR_RO(als_channel);
+static LM3533_ATTR_RW(als_en);
+static LM3533_ATTR_RO(id);
+static LM3533_ATTR_RW(linear);
+static LM3533_ATTR_RW(pwm);
+
+static struct attribute *lm3533_bl_attributes[] = {
+        &dev_attr_als_channel.attr,
+        &dev_attr_als_en.attr,
+        &dev_attr_id.attr,
+        &dev_attr_linear.attr,
+        &dev_attr_pwm.attr,
+        NULL,
+};
+
+static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj,
+                                             struct attribute *attr, int n)
+{
+        struct device *dev = container_of(kobj, struct device, kobj);
+        struct lm3533_bl *bl = dev_get_drvdata(dev);
+        umode_t mode = attr->mode;
+
+        if (attr == &dev_attr_als_channel.attr ||
+                                        attr == &dev_attr_als_en.attr) {
+                if (!bl->lm3533->have_als)
+                        mode = 0;
+        }
+
+        return mode;
+};
+
+static struct attribute_group lm3533_bl_attribute_group = {
+        .is_visible     = lm3533_bl_attr_is_visible,
+        .attrs          = lm3533_bl_attributes
+};
+
+static int __devinit lm3533_bl_setup(struct lm3533_bl *bl,
+                                        struct lm3533_bl_platform_data *pdata)
+{
+        int ret;
+
+        ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current);
+        if (ret)
+                return ret;
+
+        return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm);
+}
+
+static int __devinit lm3533_bl_probe(struct platform_device *pdev)
+{
+        struct lm3533 *lm3533;
+        struct lm3533_bl_platform_data *pdata;
+        struct lm3533_bl *bl;
+        struct backlight_device *bd;
+        struct backlight_properties props;
+        int ret;
+
+        dev_dbg(&pdev->dev, "%s\n", __func__);
+
+        lm3533 = dev_get_drvdata(pdev->dev.parent);
+        if (!lm3533)
+                return -EINVAL;
+
+        pdata = pdev->dev.platform_data;
+        if (!pdata) {
+                dev_err(&pdev->dev, "no platform data\n");
+                return -EINVAL;
+        }
+
+        if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) {
+                dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id);
+                return -EINVAL;
+        }
+
+        bl = kzalloc(sizeof(*bl), GFP_KERNEL);
+        if (!bl) {
+                dev_err(&pdev->dev,
+                                "failed to allocate memory for backlight\n");
+                return -ENOMEM;
+        }
+
+        bl->lm3533 = lm3533;
+        bl->id = pdev->id;
+
+        bl->cb.lm3533 = lm3533;
+        bl->cb.id = lm3533_bl_get_ctrlbank_id(bl);
+        bl->cb.dev = NULL;                      /* until registered */
+
+        memset(&props, 0, sizeof(props));
+        props.type = BACKLIGHT_RAW;
+        props.max_brightness = LM3533_BL_MAX_BRIGHTNESS;
+        props.brightness = pdata->default_brightness;
+        bd = backlight_device_register(pdata->name, pdev->dev.parent, bl,
+                                                &lm3533_bl_ops, &props);
+        if (IS_ERR(bd)) {
+                dev_err(&pdev->dev, "failed to register backlight device\n");
+                ret = PTR_ERR(bd);
+                goto err_free;
+        }
+
+        bl->bd = bd;
+        bl->cb.dev = &bl->bd->dev;
+
+        platform_set_drvdata(pdev, bl);
+
+        ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
+        if (ret < 0) {
+                dev_err(&pdev->dev, "failed to create sysfs attributes\n");
+                goto err_unregister;
+        }
+
+        backlight_update_status(bd);
+
+        ret = lm3533_bl_setup(bl, pdata);
+        if (ret)
+                goto err_sysfs_remove;
+
+        ret = lm3533_ctrlbank_enable(&bl->cb);
+        if (ret)
+                goto err_sysfs_remove;
+
+        return 0;
+
+err_sysfs_remove:
+        sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
+err_unregister:
+        backlight_device_unregister(bd);
+err_free:
+        kfree(bl);
+
+        return ret;
+}
+
+static int __devexit lm3533_bl_remove(struct platform_device *pdev)
+{
+        struct lm3533_bl *bl = platform_get_drvdata(pdev);
+        struct backlight_device *bd = bl->bd;
+
+        dev_dbg(&bd->dev, "%s\n", __func__);
+
+        bd->props.power = FB_BLANK_POWERDOWN;
+        bd->props.brightness = 0;
+
+        lm3533_ctrlbank_disable(&bl->cb);
+        sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
+        backlight_device_unregister(bd);
+        kfree(bl);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int lm3533_bl_suspend(struct platform_device *pdev, pm_message_t state)
+{
+        struct lm3533_bl *bl = platform_get_drvdata(pdev);
+
+        dev_dbg(&pdev->dev, "%s\n", __func__);
+
+        return lm3533_ctrlbank_disable(&bl->cb);
+}
+
+static int lm3533_bl_resume(struct platform_device *pdev)
+{
+        struct lm3533_bl *bl = platform_get_drvdata(pdev);
+
+        dev_dbg(&pdev->dev, "%s\n", __func__);
+
+        return lm3533_ctrlbank_enable(&bl->cb);
+}
+#else
+#define lm3533_bl_suspend       NULL
+#define lm3533_bl_resume        NULL
+#endif
+
+static void lm3533_bl_shutdown(struct platform_device *pdev)
+{
+        struct lm3533_bl *bl = platform_get_drvdata(pdev);
+
+        dev_dbg(&pdev->dev, "%s\n", __func__);
+
+        lm3533_ctrlbank_disable(&bl->cb);
+}
+
+static struct platform_driver lm3533_bl_driver = {
+        .driver = {
+                .name   = "lm3533-backlight",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = lm3533_bl_probe,
+        .remove         = __devexit_p(lm3533_bl_remove),
+        .shutdown       = lm3533_bl_shutdown,
+        .suspend        = lm3533_bl_suspend,
+        .resume         = lm3533_bl_resume,
+};
+module_platform_driver(lm3533_bl_driver);
+
+MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");
+MODULE_DESCRIPTION("LM3533 Backlight driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:lm3533-backlight");