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path: root/drivers/video/backlight
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Diffstat (limited to 'drivers/video/backlight')
-rw-r--r--drivers/video/backlight/backlight.c40
-rw-r--r--drivers/video/backlight/pwm_bl.c87
2 files changed, 84 insertions, 43 deletions
diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c
index bd2172c2d650..428089009cd5 100644
--- a/drivers/video/backlight/backlight.c
+++ b/drivers/video/backlight/backlight.c
@@ -23,6 +23,7 @@
static struct list_head backlight_dev_list;
static struct mutex backlight_dev_list_mutex;
+static struct blocking_notifier_head backlight_notifier;
static const char *const backlight_types[] = {
[BACKLIGHT_RAW] = "raw",
@@ -370,6 +371,9 @@ struct backlight_device *backlight_device_register(const char *name,
list_add(&new_bd->entry, &backlight_dev_list);
mutex_unlock(&backlight_dev_list_mutex);
+ blocking_notifier_call_chain(&backlight_notifier,
+ BACKLIGHT_REGISTERED, new_bd);
+
return new_bd;
}
EXPORT_SYMBOL(backlight_device_register);
@@ -413,6 +417,10 @@ void backlight_device_unregister(struct backlight_device *bd)
pmac_backlight = NULL;
mutex_unlock(&pmac_backlight_mutex);
#endif
+
+ blocking_notifier_call_chain(&backlight_notifier,
+ BACKLIGHT_UNREGISTERED, bd);
+
mutex_lock(&bd->ops_lock);
bd->ops = NULL;
mutex_unlock(&bd->ops_lock);
@@ -438,6 +446,36 @@ static int devm_backlight_device_match(struct device *dev, void *res,
}
/**
+ * backlight_register_notifier - get notified of backlight (un)registration
+ * @nb: notifier block with the notifier to call on backlight (un)registration
+ *
+ * @return 0 on success, otherwise a negative error code
+ *
+ * Register a notifier to get notified when backlight devices get registered
+ * or unregistered.
+ */
+int backlight_register_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_register(&backlight_notifier, nb);
+}
+EXPORT_SYMBOL(backlight_register_notifier);
+
+/**
+ * backlight_unregister_notifier - unregister a backlight notifier
+ * @nb: notifier block to unregister
+ *
+ * @return 0 on success, otherwise a negative error code
+ *
+ * Register a notifier to get notified when backlight devices get registered
+ * or unregistered.
+ */
+int backlight_unregister_notifier(struct notifier_block *nb)
+{
+ return blocking_notifier_chain_unregister(&backlight_notifier, nb);
+}
+EXPORT_SYMBOL(backlight_unregister_notifier);
+
+/**
* devm_backlight_device_register - resource managed backlight_device_register()
* @dev: the device to register
* @name: the name of the device
@@ -544,6 +582,8 @@ static int __init backlight_class_init(void)
backlight_class->pm = &backlight_class_dev_pm_ops;
INIT_LIST_HEAD(&backlight_dev_list);
mutex_init(&backlight_dev_list_mutex);
+ BLOCKING_INIT_NOTIFIER_HEAD(&backlight_notifier);
+
return 0;
}
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index b75201ff46f6..38ca88bc5c3e 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -10,8 +10,8 @@
* published by the Free Software Foundation.
*/
+#include <linux/gpio/consumer.h>
#include <linux/gpio.h>
-#include <linux/of_gpio.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
@@ -32,8 +32,7 @@ struct pwm_bl_data {
unsigned int *levels;
bool enabled;
struct regulator *power_supply;
- int enable_gpio;
- unsigned long enable_gpio_flags;
+ struct gpio_desc *enable_gpio;
unsigned int scale;
int (*notify)(struct device *,
int brightness);
@@ -54,12 +53,8 @@ static void pwm_backlight_power_on(struct pwm_bl_data *pb, int brightness)
if (err < 0)
dev_err(pb->dev, "failed to enable power supply\n");
- if (gpio_is_valid(pb->enable_gpio)) {
- if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
- gpio_set_value(pb->enable_gpio, 0);
- else
- gpio_set_value(pb->enable_gpio, 1);
- }
+ if (pb->enable_gpio)
+ gpiod_set_value(pb->enable_gpio, 1);
pwm_enable(pb->pwm);
pb->enabled = true;
@@ -73,12 +68,8 @@ static void pwm_backlight_power_off(struct pwm_bl_data *pb)
pwm_config(pb->pwm, 0, pb->period);
pwm_disable(pb->pwm);
- if (gpio_is_valid(pb->enable_gpio)) {
- if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
- gpio_set_value(pb->enable_gpio, 1);
- else
- gpio_set_value(pb->enable_gpio, 0);
- }
+ if (pb->enable_gpio)
+ gpiod_set_value(pb->enable_gpio, 0);
regulator_disable(pb->power_supply);
pb->enabled = false;
@@ -148,7 +139,6 @@ static int pwm_backlight_parse_dt(struct device *dev,
struct platform_pwm_backlight_data *data)
{
struct device_node *node = dev->of_node;
- enum of_gpio_flags flags;
struct property *prop;
int length;
u32 value;
@@ -189,14 +179,6 @@ static int pwm_backlight_parse_dt(struct device *dev,
data->max_brightness--;
}
- data->enable_gpio = of_get_named_gpio_flags(node, "enable-gpios", 0,
- &flags);
- if (data->enable_gpio == -EPROBE_DEFER)
- return -EPROBE_DEFER;
-
- if (gpio_is_valid(data->enable_gpio) && (flags & OF_GPIO_ACTIVE_LOW))
- data->enable_gpio_flags |= PWM_BACKLIGHT_GPIO_ACTIVE_LOW;
-
return 0;
}
@@ -256,8 +238,6 @@ static int pwm_backlight_probe(struct platform_device *pdev)
} else
pb->scale = data->max_brightness;
- pb->enable_gpio = data->enable_gpio;
- pb->enable_gpio_flags = data->enable_gpio_flags;
pb->notify = data->notify;
pb->notify_after = data->notify_after;
pb->check_fb = data->check_fb;
@@ -265,26 +245,38 @@ static int pwm_backlight_probe(struct platform_device *pdev)
pb->dev = &pdev->dev;
pb->enabled = false;
- if (gpio_is_valid(pb->enable_gpio)) {
- unsigned long flags;
-
- if (pb->enable_gpio_flags & PWM_BACKLIGHT_GPIO_ACTIVE_LOW)
- flags = GPIOF_OUT_INIT_HIGH;
+ pb->enable_gpio = devm_gpiod_get(&pdev->dev, "enable");
+ if (IS_ERR(pb->enable_gpio)) {
+ ret = PTR_ERR(pb->enable_gpio);
+ if (ret == -ENOENT)
+ pb->enable_gpio = NULL;
else
- flags = GPIOF_OUT_INIT_LOW;
+ goto err_alloc;
+ }
- ret = gpio_request_one(pb->enable_gpio, flags, "enable");
+ /*
+ * Compatibility fallback for drivers still using the integer GPIO
+ * platform data. Must go away soon.
+ */
+ if (!pb->enable_gpio && gpio_is_valid(data->enable_gpio)) {
+ ret = devm_gpio_request_one(&pdev->dev, data->enable_gpio,
+ GPIOF_OUT_INIT_HIGH, "enable");
if (ret < 0) {
dev_err(&pdev->dev, "failed to request GPIO#%d: %d\n",
- pb->enable_gpio, ret);
+ data->enable_gpio, ret);
goto err_alloc;
}
+
+ pb->enable_gpio = gpio_to_desc(data->enable_gpio);
}
+ if (pb->enable_gpio)
+ gpiod_direction_output(pb->enable_gpio, 1);
+
pb->power_supply = devm_regulator_get(&pdev->dev, "power");
if (IS_ERR(pb->power_supply)) {
ret = PTR_ERR(pb->power_supply);
- goto err_gpio;
+ goto err_alloc;
}
pb->pwm = devm_pwm_get(&pdev->dev, NULL);
@@ -295,7 +287,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
if (IS_ERR(pb->pwm)) {
dev_err(&pdev->dev, "unable to request legacy PWM\n");
ret = PTR_ERR(pb->pwm);
- goto err_gpio;
+ goto err_alloc;
}
}
@@ -304,12 +296,15 @@ static int pwm_backlight_probe(struct platform_device *pdev)
/*
* The DT case will set the pwm_period_ns field to 0 and store the
* period, parsed from the DT, in the PWM device. For the non-DT case,
- * set the period from platform data.
+ * set the period from platform data if it has not already been set
+ * via the PWM lookup table.
*/
- if (data->pwm_period_ns > 0)
+ pb->period = pwm_get_period(pb->pwm);
+ if (!pb->period && (data->pwm_period_ns > 0)) {
+ pb->period = data->pwm_period_ns;
pwm_set_period(pb->pwm, data->pwm_period_ns);
+ }
- pb->period = pwm_get_period(pb->pwm);
pb->lth_brightness = data->lth_brightness * (pb->period / pb->scale);
memset(&props, 0, sizeof(struct backlight_properties));
@@ -320,7 +315,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
if (IS_ERR(bl)) {
dev_err(&pdev->dev, "failed to register backlight\n");
ret = PTR_ERR(bl);
- goto err_gpio;
+ goto err_alloc;
}
if (data->dft_brightness > data->max_brightness) {
@@ -336,9 +331,6 @@ static int pwm_backlight_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, bl);
return 0;
-err_gpio:
- if (gpio_is_valid(pb->enable_gpio))
- gpio_free(pb->enable_gpio);
err_alloc:
if (data->exit)
data->exit(&pdev->dev);
@@ -359,6 +351,14 @@ static int pwm_backlight_remove(struct platform_device *pdev)
return 0;
}
+static void pwm_backlight_shutdown(struct platform_device *pdev)
+{
+ struct backlight_device *bl = platform_get_drvdata(pdev);
+ struct pwm_bl_data *pb = bl_get_data(bl);
+
+ pwm_backlight_power_off(pb);
+}
+
#ifdef CONFIG_PM_SLEEP
static int pwm_backlight_suspend(struct device *dev)
{
@@ -404,6 +404,7 @@ static struct platform_driver pwm_backlight_driver = {
},
.probe = pwm_backlight_probe,
.remove = pwm_backlight_remove,
+ .shutdown = pwm_backlight_shutdown,
};
module_platform_driver(pwm_backlight_driver);
generated by cgit v1.2.3 (git 2.39.0) at 2024-12-27 11:04:05 +0300