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path: root/drivers/video/backlight/gpio_backlight.c
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Diffstat (limited to 'drivers/video/backlight/gpio_backlight.c')
-rw-r--r--drivers/video/backlight/gpio_backlight.c128
1 files changed, 44 insertions, 84 deletions
diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 18e053e4716c..75409ddfba3e 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -6,29 +6,23 @@
#include <linux/backlight.h>
#include <linux/err.h>
#include <linux/fb.h>
-#include <linux/gpio.h> /* Only for legacy support */
#include <linux/gpio/consumer.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
-#include <linux/of_gpio.h>
#include <linux/platform_data/gpio_backlight.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/slab.h>
struct gpio_backlight {
- struct device *dev;
struct device *fbdev;
-
struct gpio_desc *gpiod;
- int def_value;
};
-static int gpio_backlight_update_status(struct backlight_device *bl)
+static int gpio_backlight_get_next_brightness(struct backlight_device *bl)
{
- struct gpio_backlight *gbl = bl_get_data(bl);
int brightness = bl->props.brightness;
if (bl->props.power != FB_BLANK_UNBLANK ||
@@ -36,6 +30,14 @@ static int gpio_backlight_update_status(struct backlight_device *bl)
bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
brightness = 0;
+ return brightness;
+}
+
+static int gpio_backlight_update_status(struct backlight_device *bl)
+{
+ struct gpio_backlight *gbl = bl_get_data(bl);
+ int brightness = gpio_backlight_get_next_brightness(bl);
+
gpiod_set_value_cansleep(gbl->gpiod, brightness);
return 0;
@@ -55,105 +57,63 @@ static const struct backlight_ops gpio_backlight_ops = {
.check_fb = gpio_backlight_check_fb,
};
-static int gpio_backlight_probe_dt(struct platform_device *pdev,
- struct gpio_backlight *gbl)
-{
- struct device *dev = &pdev->dev;
- int ret;
-
- gbl->def_value = device_property_read_bool(dev, "default-on");
-
- gbl->gpiod = devm_gpiod_get(dev, NULL, GPIOD_ASIS);
- if (IS_ERR(gbl->gpiod)) {
- ret = PTR_ERR(gbl->gpiod);
-
- if (ret != -EPROBE_DEFER) {
- dev_err(dev,
- "Error: The gpios parameter is missing or invalid.\n");
- }
- return ret;
- }
-
- return 0;
-}
-
-static int gpio_backlight_initial_power_state(struct gpio_backlight *gbl)
-{
- struct device_node *node = gbl->dev->of_node;
-
- /* Not booted with device tree or no phandle link to the node */
- if (!node || !node->phandle)
- return gbl->def_value ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
-
- /* if the enable GPIO is disabled, do not enable the backlight */
- if (gpiod_get_value_cansleep(gbl->gpiod) == 0)
- return FB_BLANK_POWERDOWN;
-
- return FB_BLANK_UNBLANK;
-}
-
-
static int gpio_backlight_probe(struct platform_device *pdev)
{
- struct gpio_backlight_platform_data *pdata =
- dev_get_platdata(&pdev->dev);
+ struct device *dev = &pdev->dev;
+ struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);
+ struct device_node *of_node = dev->of_node;
struct backlight_properties props;
struct backlight_device *bl;
struct gpio_backlight *gbl;
- int ret;
+ int ret, init_brightness, def_value;
- gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
+ gbl = devm_kzalloc(dev, sizeof(*gbl), GFP_KERNEL);
if (gbl == NULL)
return -ENOMEM;
- gbl->dev = &pdev->dev;
+ if (pdata)
+ gbl->fbdev = pdata->fbdev;
- if (pdev->dev.fwnode) {
- ret = gpio_backlight_probe_dt(pdev, gbl);
- if (ret)
- return ret;
- } else if (pdata) {
- /*
- * Legacy platform data GPIO retrieveal. Do not expand
- * the use of this code path, currently only used by one
- * SH board.
- */
- unsigned long flags = GPIOF_DIR_OUT;
+ def_value = device_property_read_bool(dev, "default-on");
- gbl->fbdev = pdata->fbdev;
- gbl->def_value = pdata->def_value;
- flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
-
- ret = devm_gpio_request_one(gbl->dev, pdata->gpio, flags,
- pdata ? pdata->name : "backlight");
- if (ret < 0) {
- dev_err(&pdev->dev, "unable to request GPIO\n");
- return ret;
- }
- gbl->gpiod = gpio_to_desc(pdata->gpio);
- if (!gbl->gpiod)
- return -EINVAL;
- } else {
- dev_err(&pdev->dev,
- "failed to find platform data or device tree node.\n");
- return -ENODEV;
+ gbl->gpiod = devm_gpiod_get(dev, NULL, GPIOD_ASIS);
+ if (IS_ERR(gbl->gpiod)) {
+ ret = PTR_ERR(gbl->gpiod);
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev,
+ "Error: The gpios parameter is missing or invalid.\n");
+ return ret;
}
memset(&props, 0, sizeof(props));
props.type = BACKLIGHT_RAW;
props.max_brightness = 1;
- bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
- &pdev->dev, gbl, &gpio_backlight_ops,
- &props);
+ bl = devm_backlight_device_register(dev, dev_name(dev), dev, gbl,
+ &gpio_backlight_ops, &props);
if (IS_ERR(bl)) {
- dev_err(&pdev->dev, "failed to register backlight\n");
+ dev_err(dev, "failed to register backlight\n");
return PTR_ERR(bl);
}
- bl->props.power = gpio_backlight_initial_power_state(gbl);
+ /* Set the initial power state */
+ if (!of_node || !of_node->phandle)
+ /* Not booted with device tree or no phandle link to the node */
+ bl->props.power = def_value ? FB_BLANK_UNBLANK
+ : FB_BLANK_POWERDOWN;
+ else if (gpiod_get_direction(gbl->gpiod) == 0 &&
+ gpiod_get_value_cansleep(gbl->gpiod) == 0)
+ bl->props.power = FB_BLANK_POWERDOWN;
+ else
+ bl->props.power = FB_BLANK_UNBLANK;
+
bl->props.brightness = 1;
- backlight_update_status(bl);
+ init_brightness = gpio_backlight_get_next_brightness(bl);
+ ret = gpiod_direction_output(gbl->gpiod, init_brightness);
+ if (ret) {
+ dev_err(dev, "failed to set initial brightness\n");
+ return ret;
+ }
platform_set_drvdata(pdev, bl);
return 0;