On 01/03/2015 09:04 AM, Jingoo Han wrote: > On Wednesday, December 31, 2014 12:50 PM, Aaron Lu wrote: >> >> It is useful to get the backlight device's pointer and use it to set >> backlight in some cases(the following patch will make use of it) so add >> the two APIs and export them. >> >> Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> > > Acked-by: Jingoo Han <jg1.han@xxxxxxxxxxx> Thanks for the review! Regards, Aaron > > Best regards, > Jingoo Han > >> --- >> drivers/video/backlight/backlight.c | 44 ++++++++++++++++++++++++------------- >> include/linux/backlight.h | 2 ++ >> 2 files changed, 31 insertions(+), 15 deletions(-) >> >> diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c >> index bddc8b17a4d8..bea749329236 100644 >> --- a/drivers/video/backlight/backlight.c >> +++ b/drivers/video/backlight/backlight.c >> @@ -164,28 +164,19 @@ static ssize_t brightness_show(struct device *dev, >> return sprintf(buf, "%d\n", bd->props.brightness); >> } >> >> -static ssize_t brightness_store(struct device *dev, >> - struct device_attribute *attr, const char *buf, size_t count) >> +int backlight_device_set_brightness(struct backlight_device *bd, int brightness) >> { >> - int rc; >> - struct backlight_device *bd = to_backlight_device(dev); >> - unsigned long brightness; >> - >> - rc = kstrtoul(buf, 0, &brightness); >> - if (rc) >> - return rc; >> - >> - rc = -ENXIO; >> + int rc = -ENXIO; >> >> mutex_lock(&bd->ops_lock); >> if (bd->ops) { >> if (brightness > bd->props.max_brightness) >> rc = -EINVAL; >> else { >> - pr_debug("set brightness to %lu\n", brightness); >> + pr_debug("set brightness to %u\n", brightness); >> bd->props.brightness = brightness; >> backlight_update_status(bd); >> - rc = count; >> + rc = 0; >> } >> } >> mutex_unlock(&bd->ops_lock); >> @@ -194,6 +185,23 @@ static ssize_t brightness_store(struct device *dev, >> >> return rc; >> } >> +EXPORT_SYMBOL(backlight_device_set_brightness); >> + >> +static ssize_t brightness_store(struct device *dev, >> + struct device_attribute *attr, const char *buf, size_t count) >> +{ >> + int rc; >> + struct backlight_device *bd = to_backlight_device(dev); >> + unsigned long brightness; >> + >> + rc = kstrtoul(buf, 0, &brightness); >> + if (rc) >> + return rc; >> + >> + rc = backlight_device_set_brightness(bd, brightness); >> + >> + return rc ? rc : count; >> +} >> static DEVICE_ATTR_RW(brightness); >> >> static ssize_t type_show(struct device *dev, struct device_attribute *attr, >> @@ -380,7 +388,7 @@ struct backlight_device *backlight_device_register(const char *name, >> } >> EXPORT_SYMBOL(backlight_device_register); >> >> -bool backlight_device_registered(enum backlight_type type) >> +struct backlight_device *backlight_device_get_by_type(enum backlight_type type) >> { >> bool found = false; >> struct backlight_device *bd; >> @@ -394,7 +402,13 @@ bool backlight_device_registered(enum backlight_type type) >> } >> mutex_unlock(&backlight_dev_list_mutex); >> >> - return found; >> + return found ? bd : NULL; >> +} >> +EXPORT_SYMBOL(backlight_device_get_by_type); >> + >> +bool backlight_device_registered(enum backlight_type type) >> +{ >> + return backlight_device_get_by_type(type) ? true : false; >> } >> EXPORT_SYMBOL(backlight_device_registered); >> >> diff --git a/include/linux/backlight.h b/include/linux/backlight.h >> index adb14a8616df..c59a020df3f8 100644 >> --- a/include/linux/backlight.h >> +++ b/include/linux/backlight.h >> @@ -140,6 +140,8 @@ extern void backlight_force_update(struct backlight_device *bd, >> extern bool backlight_device_registered(enum backlight_type type); >> extern int backlight_register_notifier(struct notifier_block *nb); >> extern int backlight_unregister_notifier(struct notifier_block *nb); >> +extern struct backlight_device *backlight_device_get_by_type(enum backlight_type type); >> +extern int backlight_device_set_brightness(struct backlight_device *bd, int brightness); >> >> #define to_backlight_device(obj) container_of(obj, struct backlight_device, dev) >> >> -- >> 2.1.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html