backlight: new driver for ADP5520/ADP5501 MFD PMICs

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Richard Purdie <rpurdie@linux.intel.com>

3 files changed, 390 insertions, 0 deletions

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 22a49944d98d..8b3bc71ddb04 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -251,3 +251,14 @@ config BACKLIGHT_ADX
         help
           Say Y to enable the backlight driver on Avionic Design Xanthos-based
           boards.
+
+config BACKLIGHT_ADP5520
+        tristate "Backlight Driver for ADP5520/ADP5501 using WLED"
+        depends on BACKLIGHT_CLASS_DEVICE && PMIC_ADP5520
+        help
+          If you have a LCD backlight connected to the BST/BL_SNK output of
+          ADP5520 or ADP5501, say Y here to enable this driver.
+
+          To compile this driver as a module, choose M here: the module will
+          be called adp5520_bl.
+
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index a483709205ac..9a405548874c 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -27,3 +27,5 @@ obj-$(CONFIG_BACKLIGHT_TOSA)	+= tosa_bl.o
 obj-$(CONFIG_BACKLIGHT_SAHARA)  += kb3886_bl.o
 obj-$(CONFIG_BACKLIGHT_WM831X)  += wm831x_bl.o
 obj-$(CONFIG_BACKLIGHT_ADX)    += adx_bl.o
+obj-$(CONFIG_BACKLIGHT_ADP5520) += adp5520_bl.o
+
diff --git a/drivers/video/backlight/adp5520_bl.c b/drivers/video/backlight/adp5520_bl.c
new file mode 100644
index 000000000000..ad05da5ba3c7
--- /dev/null
+++ b/drivers/video/backlight/adp5520_bl.c
@@ -0,0 +1,377 @@
+/*
+ * Backlight driver for Analog Devices ADP5520/ADP5501 MFD PMICs
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/fb.h>
+#include <linux/backlight.h>
+#include <linux/mfd/adp5520.h>
+
+struct adp5520_bl {
+        struct device *master;
+        struct adp5520_backlight_platfrom_data *pdata;
+        struct mutex lock;
+        unsigned long cached_daylight_max;
+        int id;
+        int current_brightness;
+};
+
+static int adp5520_bl_set(struct backlight_device *bl, int brightness)
+{
+        struct adp5520_bl *data = bl_get_data(bl);
+        struct device *master = data->master;
+        int ret = 0;
+
+        if (data->pdata->en_ambl_sens) {
+                if ((brightness > 0) && (brightness < ADP5020_MAX_BRIGHTNESS)) {
+                        /* Disable Ambient Light auto adjust */
+                        ret |= adp5520_clr_bits(master, BL_CONTROL,
+                                        BL_AUTO_ADJ);
+                        ret |= adp5520_write(master, DAYLIGHT_MAX, brightness);
+                } else {
+                        /*
+                         * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
+                         * restore daylight l3 sysfs brightness
+                         */
+                        ret |= adp5520_write(master, DAYLIGHT_MAX,
+                                         data->cached_daylight_max);
+                        ret |= adp5520_set_bits(master, BL_CONTROL,
+                                         BL_AUTO_ADJ);
+                }
+        } else {
+                ret |= adp5520_write(master, DAYLIGHT_MAX, brightness);
+        }
+
+        if (data->current_brightness && brightness == 0)
+                ret |= adp5520_set_bits(master,
+                                MODE_STATUS, DIM_EN);
+        else if (data->current_brightness == 0 && brightness)
+                ret |= adp5520_clr_bits(master,
+                                MODE_STATUS, DIM_EN);
+
+        if (!ret)
+                data->current_brightness = brightness;
+
+        return ret;
+}
+
+static int adp5520_bl_update_status(struct backlight_device *bl)
+{
+        int brightness = bl->props.brightness;
+        if (bl->props.power != FB_BLANK_UNBLANK)
+                brightness = 0;
+
+        if (bl->props.fb_blank != FB_BLANK_UNBLANK)
+                brightness = 0;
+
+        return adp5520_bl_set(bl, brightness);
+}
+
+static int adp5520_bl_get_brightness(struct backlight_device *bl)
+{
+        struct adp5520_bl *data = bl_get_data(bl);
+        int error;
+        uint8_t reg_val;
+
+        error = adp5520_read(data->master, BL_VALUE, &reg_val);
+
+        return error ? data->current_brightness : reg_val;
+}
+
+static struct backlight_ops adp5520_bl_ops = {
+        .update_status  = adp5520_bl_update_status,
+        .get_brightness = adp5520_bl_get_brightness,
+};
+
+static int adp5520_bl_setup(struct backlight_device *bl)
+{
+        struct adp5520_bl *data = bl_get_data(bl);
+        struct device *master = data->master;
+        struct adp5520_backlight_platfrom_data *pdata = data->pdata;
+        int ret = 0;
+
+        ret |= adp5520_write(master, DAYLIGHT_MAX, pdata->l1_daylight_max);
+        ret |= adp5520_write(master, DAYLIGHT_DIM, pdata->l1_daylight_dim);
+
+        if (pdata->en_ambl_sens) {
+                data->cached_daylight_max = pdata->l1_daylight_max;
+                ret |= adp5520_write(master, OFFICE_MAX, pdata->l2_office_max);
+                ret |= adp5520_write(master, OFFICE_DIM, pdata->l2_office_dim);
+                ret |= adp5520_write(master, DARK_MAX, pdata->l3_dark_max);
+                ret |= adp5520_write(master, DARK_DIM, pdata->l3_dark_dim);
+                ret |= adp5520_write(master, L2_TRIP, pdata->l2_trip);
+                ret |= adp5520_write(master, L2_HYS, pdata->l2_hyst);
+                ret |= adp5520_write(master, L3_TRIP, pdata->l3_trip);
+                ret |= adp5520_write(master, L3_HYS, pdata->l3_hyst);
+                ret |= adp5520_write(master, ALS_CMPR_CFG,
+                        ALS_CMPR_CFG_VAL(pdata->abml_filt, L3_EN));
+        }
+
+        ret |= adp5520_write(master, BL_CONTROL,
+                        BL_CTRL_VAL(pdata->fade_led_law, pdata->en_ambl_sens));
+
+        ret |= adp5520_write(master, BL_FADE, FADE_VAL(pdata->fade_in,
+                        pdata->fade_out));
+
+        ret |= adp5520_set_bits(master, MODE_STATUS, BL_EN | DIM_EN);
+
+        return ret;
+}
+
+static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
+{
+        struct adp5520_bl *data = dev_get_drvdata(dev);
+        int error;
+        uint8_t reg_val;
+
+        mutex_lock(&data->lock);
+        error = adp5520_read(data->master, reg, &reg_val);
+        mutex_unlock(&data->lock);
+
+        return sprintf(buf, "%u\n", reg_val);
+}
+
+static ssize_t adp5520_store(struct device *dev, const char *buf,
+                         size_t count, int reg)
+{
+        struct adp5520_bl *data = dev_get_drvdata(dev);
+        unsigned long val;
+        int ret;
+
+        ret = strict_strtoul(buf, 10, &val);
+        if (ret)
+                return ret;
+
+        mutex_lock(&data->lock);
+        adp5520_write(data->master, reg, val);
+        mutex_unlock(&data->lock);
+
+        return count;
+}
+
+static ssize_t adp5520_bl_dark_max_show(struct device *dev,
+                struct device_attribute *attr, char *buf)
+{
+        return adp5520_show(dev, buf, DARK_MAX);
+}
+
+static ssize_t adp5520_bl_dark_max_store(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        return adp5520_store(dev, buf, count, DARK_MAX);
+}
+static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
+                        adp5520_bl_dark_max_store);
+
+static ssize_t adp5520_bl_office_max_show(struct device *dev,
+                                     struct device_attribute *attr, char *buf)
+{
+        return adp5520_show(dev, buf, OFFICE_MAX);
+}
+
+static ssize_t adp5520_bl_office_max_store(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        return adp5520_store(dev, buf, count, OFFICE_MAX);
+}
+static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
+                        adp5520_bl_office_max_store);
+
+static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
+                        struct device_attribute *attr, char *buf)
+{
+        return adp5520_show(dev, buf, DAYLIGHT_MAX);
+}
+
+static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct adp5520_bl *data = dev_get_drvdata(dev);
+
+        strict_strtoul(buf, 10, &data->cached_daylight_max);
+        return adp5520_store(dev, buf, count, DAYLIGHT_MAX);
+}
+static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
+                        adp5520_bl_daylight_max_store);
+
+static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
+                        struct device_attribute *attr, char *buf)
+{
+        return adp5520_show(dev, buf, DARK_DIM);
+}
+
+static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
+                                     struct device_attribute *attr,
+                                     const char *buf, size_t count)
+{
+        return adp5520_store(dev, buf, count, DARK_DIM);
+}
+static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
+                        adp5520_bl_dark_dim_store);
+
+static ssize_t adp5520_bl_office_dim_show(struct device *dev,
+                        struct device_attribute *attr, char *buf)
+{
+        return adp5520_show(dev, buf, OFFICE_DIM);
+}
+
+static ssize_t adp5520_bl_office_dim_store(struct device *dev,
+                                     struct device_attribute *attr,
+                                     const char *buf, size_t count)
+{
+        return adp5520_store(dev, buf, count, OFFICE_DIM);
+}
+static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
+                        adp5520_bl_office_dim_store);
+
+static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
+                                     struct device_attribute *attr, char *buf)
+{
+        return adp5520_show(dev, buf, DAYLIGHT_DIM);
+}
+
+static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
+                                     struct device_attribute *attr,
+                                     const char *buf, size_t count)
+{
+        return adp5520_store(dev, buf, count, DAYLIGHT_DIM);
+}
+static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
+                        adp5520_bl_daylight_dim_store);
+
+static struct attribute *adp5520_bl_attributes[] = {
+        &dev_attr_dark_max.attr,
+        &dev_attr_dark_dim.attr,
+        &dev_attr_office_max.attr,
+        &dev_attr_office_dim.attr,
+        &dev_attr_daylight_max.attr,
+        &dev_attr_daylight_dim.attr,
+        NULL
+};
+
+static const struct attribute_group adp5520_bl_attr_group = {
+        .attrs = adp5520_bl_attributes,
+};
+
+static int __devinit adp5520_bl_probe(struct platform_device *pdev)
+{
+        struct backlight_device *bl;
+        struct adp5520_bl *data;
+        int ret = 0;
+
+        data = kzalloc(sizeof(*data), GFP_KERNEL);
+        if (data == NULL)
+                return -ENOMEM;
+
+        data->master = pdev->dev.parent;
+        data->pdata = pdev->dev.platform_data;
+
+        if (data->pdata  == NULL) {
+                dev_err(&pdev->dev, "missing platform data\n");
+                kfree(data);
+                return -ENODEV;
+        }
+
+        data->id = pdev->id;
+        data->current_brightness = 0;
+
+        mutex_init(&data->lock);
+
+        bl = backlight_device_register(pdev->name, data->master,
+                        data, &adp5520_bl_ops);
+        if (IS_ERR(bl)) {
+                dev_err(&pdev->dev, "failed to register backlight\n");
+                kfree(data);
+                return PTR_ERR(bl);
+        }
+
+        bl->props.max_brightness =
+                bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
+
+        if (data->pdata->en_ambl_sens)
+                ret = sysfs_create_group(&bl->dev.kobj,
+                        &adp5520_bl_attr_group);
+
+        if (ret) {
+                dev_err(&pdev->dev, "failed to register sysfs\n");
+                backlight_device_unregister(bl);
+                kfree(data);
+        }
+
+        platform_set_drvdata(pdev, bl);
+        ret |= adp5520_bl_setup(bl);
+        backlight_update_status(bl);
+
+        return ret;
+}
+
+static int __devexit adp5520_bl_remove(struct platform_device *pdev)
+{
+        struct backlight_device *bl = platform_get_drvdata(pdev);
+        struct adp5520_bl *data = bl_get_data(bl);
+
+        adp5520_clr_bits(data->master, MODE_STATUS, BL_EN);
+
+        if (data->pdata->en_ambl_sens)
+                sysfs_remove_group(&bl->dev.kobj,
+                                &adp5520_bl_attr_group);
+
+        backlight_device_unregister(bl);
+        kfree(data);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int adp5520_bl_suspend(struct platform_device *pdev,
+                                 pm_message_t state)
+{
+        struct backlight_device *bl = platform_get_drvdata(pdev);
+        return adp5520_bl_set(bl, 0);
+}
+
+static int adp5520_bl_resume(struct platform_device *pdev)
+{
+        struct backlight_device *bl = platform_get_drvdata(pdev);
+
+        backlight_update_status(bl);
+        return 0;
+}
+#else
+#define adp5520_bl_suspend      NULL
+#define adp5520_bl_resume       NULL
+#endif
+
+static struct platform_driver adp5520_bl_driver = {
+        .driver         = {
+                .name   = "adp5520-backlight",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = adp5520_bl_probe,
+        .remove         = __devexit_p(adp5520_bl_remove),
+        .suspend        = adp5520_bl_suspend,
+        .resume         = adp5520_bl_resume,
+};
+
+static int __init adp5520_bl_init(void)
+{
+        return platform_driver_register(&adp5520_bl_driver);
+}
+module_init(adp5520_bl_init);
+
+static void __exit adp5520_bl_exit(void)
+{
+        platform_driver_unregister(&adp5520_bl_driver);
+}
+module_exit(adp5520_bl_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:adp5520-backlight");