| Message ID | 20190708103547.23528-1-jjhiblot@ti.com |
|---|---|
| Headers | show |
| Series | leds: Add control of the voltage/current regulator to the LED core | expand |
JJ On 7/8/19 5:35 AM, Jean-Jacques Hiblot wrote: > A LED is usually powered by a voltage/current regulator. Let the LED core Let the LED core know > about it. This allows the LED core to turn on or off the power supply > as needed. > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> > --- > drivers/leds/led-class.c | 10 ++++++++ > drivers/leds/led-core.c | 53 +++++++++++++++++++++++++++++++++++++--- > include/linux/leds.h | 4 +++ > 3 files changed, 64 insertions(+), 3 deletions(-) > > diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c > index 4793e77808e2..e01b2d982564 100644 > --- a/drivers/leds/led-class.c > +++ b/drivers/leds/led-class.c > @@ -17,6 +17,7 @@ > #include <linux/slab.h> > #include <linux/spinlock.h> > #include <linux/timer.h> > +#include <linux/regulator/consumer.h> What if you move this to leds.h so core and class can both include it. > #include <uapi/linux/uleds.h> > #include "leds.h" > > @@ -272,6 +273,15 @@ int of_led_classdev_register(struct device *parent, struct device_node *np, > dev_warn(parent, "Led %s renamed to %s due to name collision", > led_cdev->name, dev_name(led_cdev->dev)); > > + led_cdev->regulator = devm_regulator_get(led_cdev->dev, "power"); Is the regulator always going to be called power? > + if (IS_ERR(led_cdev->regulator)) { > + dev_err(led_cdev->dev, "Cannot get the power supply for %s\n", > + led_cdev->name); > + device_unregister(led_cdev->dev); > + mutex_unlock(&led_cdev->led_access); > + return PTR_ERR(led_cdev->regulator); This is listed as optional in the DT doc. This appears to be required. I prefer to keep it optional. Many LED drivers are connected to fixed non-managed supplies. > + } > + > if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) { > ret = led_add_brightness_hw_changed(led_cdev); > if (ret) { > diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c > index 7107cd7e87cf..139de6b08cad 100644 > --- a/drivers/leds/led-core.c > +++ b/drivers/leds/led-core.c > @@ -16,6 +16,7 @@ > #include <linux/rwsem.h> > #include <linux/slab.h> > #include "leds.h" > +#include <linux/regulator/consumer.h> > > DECLARE_RWSEM(leds_list_lock); > EXPORT_SYMBOL_GPL(leds_list_lock); > @@ -23,6 +24,31 @@ EXPORT_SYMBOL_GPL(leds_list_lock); > LIST_HEAD(leds_list); > EXPORT_SYMBOL_GPL(leds_list); > > +static bool __led_need_regulator_update(struct led_classdev *led_cdev, > + int brightness) > +{ > + bool new_regulator_state = (brightness != LED_OFF); > + > + return led_cdev->regulator_state != new_regulator_state; > +} > + > +static int __led_handle_regulator(struct led_classdev *led_cdev, > + int brightness) > +{ > + if (__led_need_regulator_update(led_cdev, brightness)) { > + int ret; Prefer to this to be moved up. > + > + if (brightness != LED_OFF) > + ret = regulator_enable(led_cdev->regulator); > + else > + ret = regulator_disable(led_cdev->regulator); > + if (ret) > + return ret; new line > + led_cdev->regulator_state = (brightness != LED_OFF); > + } > + return 0; > +} > + > static int __led_set_brightness(struct led_classdev *led_cdev, > enum led_brightness value) > { > @@ -80,6 +106,7 @@ static void led_timer_function(struct timer_list *t) > } > > led_set_brightness_nosleep(led_cdev, brightness); > + __led_handle_regulator(led_cdev, brightness); Again this seems to indicate that the regulator is a required property for the LEDs This needs to be made optional. And the same comment through out for every call. > > /* Return in next iteration if led is in one-shot mode and we are in > * the final blink state so that the led is toggled each delay_on + > @@ -115,6 +142,8 @@ static void set_brightness_delayed(struct work_struct *ws) > if (ret == -ENOTSUPP) > ret = __led_set_brightness_blocking(led_cdev, > led_cdev->delayed_set_value); > + __led_handle_regulator(led_cdev, led_cdev->delayed_set_value); > + > if (ret < 0 && > /* LED HW might have been unplugged, therefore don't warn */ > !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) && > @@ -141,6 +170,7 @@ static void led_set_software_blink(struct led_classdev *led_cdev, > /* never on - just set to off */ > if (!delay_on) { > led_set_brightness_nosleep(led_cdev, LED_OFF); > + __led_handle_regulator(led_cdev, LED_OFF); > return; > } > > @@ -148,6 +178,7 @@ static void led_set_software_blink(struct led_classdev *led_cdev, > if (!delay_off) { > led_set_brightness_nosleep(led_cdev, > led_cdev->blink_brightness); > + __led_handle_regulator(led_cdev, led_cdev->blink_brightness); > return; > } > > @@ -256,8 +287,14 @@ void led_set_brightness_nopm(struct led_classdev *led_cdev, > enum led_brightness value) > { > /* Use brightness_set op if available, it is guaranteed not to sleep */ > - if (!__led_set_brightness(led_cdev, value)) > - return; > + if (!__led_set_brightness(led_cdev, value)) { > + /* > + * if regulator state doesn't need to be changed, that is all/ > + * Otherwise delegate the change to a work queue > + */ > + if (!__led_need_regulator_update(led_cdev, value)) > + return; > + } > > /* If brightness setting can sleep, delegate it to a work queue task */ > led_cdev->delayed_set_value = value; > @@ -280,6 +317,8 @@ EXPORT_SYMBOL_GPL(led_set_brightness_nosleep); > int led_set_brightness_sync(struct led_classdev *led_cdev, > enum led_brightness value) > { > + int ret; > + > if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) > return -EBUSY; > > @@ -288,7 +327,15 @@ int led_set_brightness_sync(struct led_classdev *led_cdev, > if (led_cdev->flags & LED_SUSPENDED) > return 0; > > - return __led_set_brightness_blocking(led_cdev, led_cdev->brightness); > + ret = __led_set_brightness_blocking(led_cdev, led_cdev->brightness); > + if (ret) > + return ret; > + > + ret = __led_handle_regulator(led_cdev, led_cdev->brightness); Can't you just return here? Dan > + if (ret) > + return ret; > + > + return 0; > } > EXPORT_SYMBOL_GPL(led_set_brightness_sync); > > diff --git a/include/linux/leds.h b/include/linux/leds.h > index 9b2bf574a17a..bee8e3f8dddd 100644 > --- a/include/linux/leds.h > +++ b/include/linux/leds.h > @@ -123,6 +123,10 @@ struct led_classdev { > > /* Ensures consistent access to the LED Flash Class device */ > struct mutex led_access; > + > + /* regulator */ > + struct regulator *regulator; > + bool regulator_state; > }; > > extern int of_led_classdev_register(struct device *parent,
Hi Dan, On 12/07/2019 20:49, Dan Murphy wrote: > JJ > > On 7/8/19 5:35 AM, Jean-Jacques Hiblot wrote: >> A LED is usually powered by a voltage/current regulator. Let the LED >> core > Let the LED core know >> about it. This allows the LED core to turn on or off the power supply >> as needed. > >> >> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> >> --- >> drivers/leds/led-class.c | 10 ++++++++ >> drivers/leds/led-core.c | 53 +++++++++++++++++++++++++++++++++++++--- >> include/linux/leds.h | 4 +++ >> 3 files changed, 64 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c >> index 4793e77808e2..e01b2d982564 100644 >> --- a/drivers/leds/led-class.c >> +++ b/drivers/leds/led-class.c >> @@ -17,6 +17,7 @@ >> #include <linux/slab.h> >> #include <linux/spinlock.h> >> #include <linux/timer.h> >> +#include <linux/regulator/consumer.h> > > What if you move this to leds.h so core and class can both include it. > > >> #include <uapi/linux/uleds.h> >> #include "leds.h" >> @@ -272,6 +273,15 @@ int of_led_classdev_register(struct device >> *parent, struct device_node *np, >> dev_warn(parent, "Led %s renamed to %s due to name collision", >> led_cdev->name, dev_name(led_cdev->dev)); >> + led_cdev->regulator = devm_regulator_get(led_cdev->dev, "power"); > > Is the regulator always going to be called power? Actually in the dts, that will be "power-supply". I lacked the imagination to come up with a better name. > >> + if (IS_ERR(led_cdev->regulator)) { >> + dev_err(led_cdev->dev, "Cannot get the power supply for %s\n", >> + led_cdev->name); >> + device_unregister(led_cdev->dev); >> + mutex_unlock(&led_cdev->led_access); >> + return PTR_ERR(led_cdev->regulator); > > This is listed as optional in the DT doc. This appears to be required. The regulator core will provide a dummy regulator if none is given in the device tree. I would rather have an error in that case, but that is not how it works. > > I prefer to keep it optional. Many LED drivers are connected to fixed > non-managed supplies. > >> + } >> + >> if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) { >> ret = led_add_brightness_hw_changed(led_cdev); >> if (ret) { >> diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c >> index 7107cd7e87cf..139de6b08cad 100644 >> --- a/drivers/leds/led-core.c >> +++ b/drivers/leds/led-core.c >> @@ -16,6 +16,7 @@ >> #include <linux/rwsem.h> >> #include <linux/slab.h> >> #include "leds.h" >> +#include <linux/regulator/consumer.h> >> DECLARE_RWSEM(leds_list_lock); >> EXPORT_SYMBOL_GPL(leds_list_lock); >> @@ -23,6 +24,31 @@ EXPORT_SYMBOL_GPL(leds_list_lock); >> LIST_HEAD(leds_list); >> EXPORT_SYMBOL_GPL(leds_list); >> +static bool __led_need_regulator_update(struct led_classdev >> *led_cdev, >> + int brightness) >> +{ >> + bool new_regulator_state = (brightness != LED_OFF); >> + >> + return led_cdev->regulator_state != new_regulator_state; >> +} >> + >> +static int __led_handle_regulator(struct led_classdev *led_cdev, >> + int brightness) >> +{ >> + if (__led_need_regulator_update(led_cdev, brightness)) { >> + int ret; > > Prefer to this to be moved up. ok > >> + >> + if (brightness != LED_OFF) >> + ret = regulator_enable(led_cdev->regulator); >> + else >> + ret = regulator_disable(led_cdev->regulator); >> + if (ret) >> + return ret; > new line >> + led_cdev->regulator_state = (brightness != LED_OFF); >> + } >> + return 0; >> +} >> + >> static int __led_set_brightness(struct led_classdev *led_cdev, >> enum led_brightness value) >> { >> @@ -80,6 +106,7 @@ static void led_timer_function(struct timer_list *t) >> } >> led_set_brightness_nosleep(led_cdev, brightness); >> + __led_handle_regulator(led_cdev, brightness); > > Again this seems to indicate that the regulator is a required property > for the LEDs > > This needs to be made optional. And the same comment through out for > every call. > > >> /* Return in next iteration if led is in one-shot mode and we >> are in >> * the final blink state so that the led is toggled each >> delay_on + >> @@ -115,6 +142,8 @@ static void set_brightness_delayed(struct >> work_struct *ws) >> if (ret == -ENOTSUPP) >> ret = __led_set_brightness_blocking(led_cdev, >> led_cdev->delayed_set_value); >> + __led_handle_regulator(led_cdev, led_cdev->delayed_set_value); >> + >> if (ret < 0 && >> /* LED HW might have been unplugged, therefore don't warn */ >> !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) && >> @@ -141,6 +170,7 @@ static void led_set_software_blink(struct >> led_classdev *led_cdev, >> /* never on - just set to off */ >> if (!delay_on) { >> led_set_brightness_nosleep(led_cdev, LED_OFF); >> + __led_handle_regulator(led_cdev, LED_OFF); >> return; >> } >> @@ -148,6 +178,7 @@ static void led_set_software_blink(struct >> led_classdev *led_cdev, >> if (!delay_off) { >> led_set_brightness_nosleep(led_cdev, >> led_cdev->blink_brightness); >> + __led_handle_regulator(led_cdev, led_cdev->blink_brightness); >> return; >> } >> @@ -256,8 +287,14 @@ void led_set_brightness_nopm(struct >> led_classdev *led_cdev, >> enum led_brightness value) >> { >> /* Use brightness_set op if available, it is guaranteed not to >> sleep */ >> - if (!__led_set_brightness(led_cdev, value)) >> - return; >> + if (!__led_set_brightness(led_cdev, value)) { >> + /* >> + * if regulator state doesn't need to be changed, that is all/ >> + * Otherwise delegate the change to a work queue >> + */ >> + if (!__led_need_regulator_update(led_cdev, value)) >> + return; >> + } >> /* If brightness setting can sleep, delegate it to a work >> queue task */ >> led_cdev->delayed_set_value = value; >> @@ -280,6 +317,8 @@ EXPORT_SYMBOL_GPL(led_set_brightness_nosleep); >> int led_set_brightness_sync(struct led_classdev *led_cdev, >> enum led_brightness value) >> { >> + int ret; >> + >> if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) >> return -EBUSY; >> @@ -288,7 +327,15 @@ int led_set_brightness_sync(struct >> led_classdev *led_cdev, >> if (led_cdev->flags & LED_SUSPENDED) >> return 0; >> - return __led_set_brightness_blocking(led_cdev, >> led_cdev->brightness); >> + ret = __led_set_brightness_blocking(led_cdev, >> led_cdev->brightness); >> + if (ret) >> + return ret; >> + >> + ret = __led_handle_regulator(led_cdev, led_cdev->brightness); > > Can't you just return here? ok thanks for the review JJ > > Dan > >> + if (ret) >> + return ret; >> + >> + return 0; >> } >> EXPORT_SYMBOL_GPL(led_set_brightness_sync); >> diff --git a/include/linux/leds.h b/include/linux/leds.h >> index 9b2bf574a17a..bee8e3f8dddd 100644 >> --- a/include/linux/leds.h >> +++ b/include/linux/leds.h >> @@ -123,6 +123,10 @@ struct led_classdev { >> /* Ensures consistent access to the LED Flash Class device */ >> struct mutex led_access; >> + >> + /* regulator */ >> + struct regulator *regulator; >> + bool regulator_state; >> }; >> extern int of_led_classdev_register(struct device *parent,
On Mon, Jul 15, 2019 at 11:01:29AM +0200, Jean-Jacques Hiblot wrote: > Hi Dan, > > On 12/07/2019 20:49, Dan Murphy wrote: > > JJ > > > > On 7/8/19 5:35 AM, Jean-Jacques Hiblot wrote: > > > A LED is usually powered by a voltage/current regulator. Let the LED > > > core > > Let the LED core know > > > about it. This allows the LED core to turn on or off the power supply > > > as needed. > > > > > > > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> > > > --- > > > drivers/leds/led-class.c | 10 ++++++++ > > > drivers/leds/led-core.c | 53 +++++++++++++++++++++++++++++++++++++--- > > > include/linux/leds.h | 4 +++ > > > 3 files changed, 64 insertions(+), 3 deletions(-) > > > > > > diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c > > > index 4793e77808e2..e01b2d982564 100644 > > > --- a/drivers/leds/led-class.c > > > +++ b/drivers/leds/led-class.c > > > @@ -17,6 +17,7 @@ > > > #include <linux/slab.h> > > > #include <linux/spinlock.h> > > > #include <linux/timer.h> > > > +#include <linux/regulator/consumer.h> > > > > What if you move this to leds.h so core and class can both include it. > > > > > > > #include <uapi/linux/uleds.h> > > > #include "leds.h" > > > @@ -272,6 +273,15 @@ int of_led_classdev_register(struct device > > > *parent, struct device_node *np, > > > dev_warn(parent, "Led %s renamed to %s due to name collision", > > > led_cdev->name, dev_name(led_cdev->dev)); > > > + led_cdev->regulator = devm_regulator_get(led_cdev->dev, "power"); > > > > Is the regulator always going to be called power? > > Actually in the dts, that will be "power-supply". I lacked the imagination > to come up with a better name. > > > > > > > > + if (IS_ERR(led_cdev->regulator)) { > > > + dev_err(led_cdev->dev, "Cannot get the power supply for %s\n", > > > + led_cdev->name); > > > + device_unregister(led_cdev->dev); > > > + mutex_unlock(&led_cdev->led_access); > > > + return PTR_ERR(led_cdev->regulator); > > > > This is listed as optional in the DT doc. This appears to be required. > > The regulator core will provide a dummy regulator if none is given in the > device tree. I would rather have an error in that case, but that is not how > it works. If you actively wanted to get -ENODEV back when there is no regulator then you can use devm_regulator_get_optional() for that. However perhaps be careful what you wish for. If you use get_optional() then you will have to sprinkle NULL or IS_ERR() checks everywhere. I'd favour using the current approach! Daniel. > > > > > > I prefer to keep it optional. Many LED drivers are connected to fixed > > non-managed supplies. > > > > > + } > > > + > > > if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) { > > > ret = led_add_brightness_hw_changed(led_cdev); > > > if (ret) { > > > diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c > > > index 7107cd7e87cf..139de6b08cad 100644 > > > --- a/drivers/leds/led-core.c > > > +++ b/drivers/leds/led-core.c > > > @@ -16,6 +16,7 @@ > > > #include <linux/rwsem.h> > > > #include <linux/slab.h> > > > #include "leds.h" > > > +#include <linux/regulator/consumer.h> > > > DECLARE_RWSEM(leds_list_lock); > > > EXPORT_SYMBOL_GPL(leds_list_lock); > > > @@ -23,6 +24,31 @@ EXPORT_SYMBOL_GPL(leds_list_lock); > > > LIST_HEAD(leds_list); > > > EXPORT_SYMBOL_GPL(leds_list); > > > +static bool __led_need_regulator_update(struct led_classdev > > > *led_cdev, > > > + int brightness) > > > +{ > > > + bool new_regulator_state = (brightness != LED_OFF); > > > + > > > + return led_cdev->regulator_state != new_regulator_state; > > > +} > > > + > > > +static int __led_handle_regulator(struct led_classdev *led_cdev, > > > + int brightness) > > > +{ > > > + if (__led_need_regulator_update(led_cdev, brightness)) { > > > + int ret; > > > > Prefer to this to be moved up. > ok > > > > > + > > > + if (brightness != LED_OFF) > > > + ret = regulator_enable(led_cdev->regulator); > > > + else > > > + ret = regulator_disable(led_cdev->regulator); > > > + if (ret) > > > + return ret; > > new line > > > + led_cdev->regulator_state = (brightness != LED_OFF); > > > + } > > > + return 0; > > > +} > > > + > > > static int __led_set_brightness(struct led_classdev *led_cdev, > > > enum led_brightness value) > > > { > > > @@ -80,6 +106,7 @@ static void led_timer_function(struct timer_list *t) > > > } > > > led_set_brightness_nosleep(led_cdev, brightness); > > > + __led_handle_regulator(led_cdev, brightness); > > > > Again this seems to indicate that the regulator is a required property > > for the LEDs > > > > This needs to be made optional. And the same comment through out for > > every call. > > > > > > > /* Return in next iteration if led is in one-shot mode and > > > we are in > > > * the final blink state so that the led is toggled each > > > delay_on + > > > @@ -115,6 +142,8 @@ static void set_brightness_delayed(struct > > > work_struct *ws) > > > if (ret == -ENOTSUPP) > > > ret = __led_set_brightness_blocking(led_cdev, > > > led_cdev->delayed_set_value); > > > + __led_handle_regulator(led_cdev, led_cdev->delayed_set_value); > > > + > > > if (ret < 0 && > > > /* LED HW might have been unplugged, therefore don't warn */ > > > !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) && > > > @@ -141,6 +170,7 @@ static void led_set_software_blink(struct > > > led_classdev *led_cdev, > > > /* never on - just set to off */ > > > if (!delay_on) { > > > led_set_brightness_nosleep(led_cdev, LED_OFF); > > > + __led_handle_regulator(led_cdev, LED_OFF); > > > return; > > > } > > > @@ -148,6 +178,7 @@ static void led_set_software_blink(struct > > > led_classdev *led_cdev, > > > if (!delay_off) { > > > led_set_brightness_nosleep(led_cdev, > > > led_cdev->blink_brightness); > > > + __led_handle_regulator(led_cdev, led_cdev->blink_brightness); > > > return; > > > } > > > @@ -256,8 +287,14 @@ void led_set_brightness_nopm(struct > > > led_classdev *led_cdev, > > > enum led_brightness value) > > > { > > > /* Use brightness_set op if available, it is guaranteed not to > > > sleep */ > > > - if (!__led_set_brightness(led_cdev, value)) > > > - return; > > > + if (!__led_set_brightness(led_cdev, value)) { > > > + /* > > > + * if regulator state doesn't need to be changed, that is all/ > > > + * Otherwise delegate the change to a work queue > > > + */ > > > + if (!__led_need_regulator_update(led_cdev, value)) > > > + return; > > > + } > > > /* If brightness setting can sleep, delegate it to a work > > > queue task */ > > > led_cdev->delayed_set_value = value; > > > @@ -280,6 +317,8 @@ EXPORT_SYMBOL_GPL(led_set_brightness_nosleep); > > > int led_set_brightness_sync(struct led_classdev *led_cdev, > > > enum led_brightness value) > > > { > > > + int ret; > > > + > > > if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) > > > return -EBUSY; > > > @@ -288,7 +327,15 @@ int led_set_brightness_sync(struct > > > led_classdev *led_cdev, > > > if (led_cdev->flags & LED_SUSPENDED) > > > return 0; > > > - return __led_set_brightness_blocking(led_cdev, > > > led_cdev->brightness); > > > + ret = __led_set_brightness_blocking(led_cdev, > > > led_cdev->brightness); > > > + if (ret) > > > + return ret; > > > + > > > + ret = __led_handle_regulator(led_cdev, led_cdev->brightness); > > > > Can't you just return here? > > ok > > > thanks for the review > > JJ > > > > > Dan > > > > > + if (ret) > > > + return ret; > > > + > > > + return 0; > > > } > > > EXPORT_SYMBOL_GPL(led_set_brightness_sync); > > > diff --git a/include/linux/leds.h b/include/linux/leds.h > > > index 9b2bf574a17a..bee8e3f8dddd 100644 > > > --- a/include/linux/leds.h > > > +++ b/include/linux/leds.h > > > @@ -123,6 +123,10 @@ struct led_classdev { > > > /* Ensures consistent access to the LED Flash Class device */ > > > struct mutex led_access; > > > + > > > + /* regulator */ > > > + struct regulator *regulator; > > > + bool regulator_state; > > > }; > > > extern int of_led_classdev_register(struct device *parent,
On 15/07/2019 11:24, Daniel Thompson wrote: > On Mon, Jul 15, 2019 at 11:01:29AM +0200, Jean-Jacques Hiblot wrote: >> Hi Dan, >> >> On 12/07/2019 20:49, Dan Murphy wrote: >>> JJ >>> >>> On 7/8/19 5:35 AM, Jean-Jacques Hiblot wrote: >>>> A LED is usually powered by a voltage/current regulator. Let the LED >>>> core >>> Let the LED core know >>>> about it. This allows the LED core to turn on or off the power supply >>>> as needed. >>>> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com> >>>> --- >>>> drivers/leds/led-class.c | 10 ++++++++ >>>> drivers/leds/led-core.c | 53 +++++++++++++++++++++++++++++++++++++--- >>>> include/linux/leds.h | 4 +++ >>>> 3 files changed, 64 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c >>>> index 4793e77808e2..e01b2d982564 100644 >>>> --- a/drivers/leds/led-class.c >>>> +++ b/drivers/leds/led-class.c >>>> @@ -17,6 +17,7 @@ >>>> #include <linux/slab.h> >>>> #include <linux/spinlock.h> >>>> #include <linux/timer.h> >>>> +#include <linux/regulator/consumer.h> >>> What if you move this to leds.h so core and class can both include it. >>> >>> >>>> #include <uapi/linux/uleds.h> >>>> #include "leds.h" >>>> @@ -272,6 +273,15 @@ int of_led_classdev_register(struct device >>>> *parent, struct device_node *np, >>>> dev_warn(parent, "Led %s renamed to %s due to name collision", >>>> led_cdev->name, dev_name(led_cdev->dev)); >>>> + led_cdev->regulator = devm_regulator_get(led_cdev->dev, "power"); >>> Is the regulator always going to be called power? >> Actually in the dts, that will be "power-supply". I lacked the imagination >> to come up with a better name. >> >> >> >>>> + if (IS_ERR(led_cdev->regulator)) { >>>> + dev_err(led_cdev->dev, "Cannot get the power supply for %s\n", >>>> + led_cdev->name); >>>> + device_unregister(led_cdev->dev); >>>> + mutex_unlock(&led_cdev->led_access); >>>> + return PTR_ERR(led_cdev->regulator); >>> This is listed as optional in the DT doc. This appears to be required. >> The regulator core will provide a dummy regulator if none is given in the >> device tree. I would rather have an error in that case, but that is not how >> it works. > If you actively wanted to get -ENODEV back when there is no regulator > then you can use devm_regulator_get_optional() for that. > > However perhaps be careful what you wish for. If you use get_optional() > then you will have to sprinkle NULL or IS_ERR() checks everywhere. I'd > favour using the current approach! Thanks for the info. I think I'll use the get_optionnal(). That will add a bit of complexity, but it will avoid deferring some work in led_set_brightness_nopm() when it is not needed. JJ > > > Daniel. > >> >>> I prefer to keep it optional. Many LED drivers are connected to fixed >>> non-managed supplies. >>> >>>> + } >>>> + >>>> if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) { >>>> ret = led_add_brightness_hw_changed(led_cdev); >>>> if (ret) { >>>> diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c >>>> index 7107cd7e87cf..139de6b08cad 100644 >>>> --- a/drivers/leds/led-core.c >>>> +++ b/drivers/leds/led-core.c >>>> @@ -16,6 +16,7 @@ >>>> #include <linux/rwsem.h> >>>> #include <linux/slab.h> >>>> #include "leds.h" >>>> +#include <linux/regulator/consumer.h> >>>> DECLARE_RWSEM(leds_list_lock); >>>> EXPORT_SYMBOL_GPL(leds_list_lock); >>>> @@ -23,6 +24,31 @@ EXPORT_SYMBOL_GPL(leds_list_lock); >>>> LIST_HEAD(leds_list); >>>> EXPORT_SYMBOL_GPL(leds_list); >>>> +static bool __led_need_regulator_update(struct led_classdev >>>> *led_cdev, >>>> + int brightness) >>>> +{ >>>> + bool new_regulator_state = (brightness != LED_OFF); >>>> + >>>> + return led_cdev->regulator_state != new_regulator_state; >>>> +} >>>> + >>>> +static int __led_handle_regulator(struct led_classdev *led_cdev, >>>> + int brightness) >>>> +{ >>>> + if (__led_need_regulator_update(led_cdev, brightness)) { >>>> + int ret; >>> Prefer to this to be moved up. >> ok >>>> + >>>> + if (brightness != LED_OFF) >>>> + ret = regulator_enable(led_cdev->regulator); >>>> + else >>>> + ret = regulator_disable(led_cdev->regulator); >>>> + if (ret) >>>> + return ret; >>> new line >>>> + led_cdev->regulator_state = (brightness != LED_OFF); >>>> + } >>>> + return 0; >>>> +} >>>> + >>>> static int __led_set_brightness(struct led_classdev *led_cdev, >>>> enum led_brightness value) >>>> { >>>> @@ -80,6 +106,7 @@ static void led_timer_function(struct timer_list *t) >>>> } >>>> led_set_brightness_nosleep(led_cdev, brightness); >>>> + __led_handle_regulator(led_cdev, brightness); >>> Again this seems to indicate that the regulator is a required property >>> for the LEDs >>> >>> This needs to be made optional. And the same comment through out for >>> every call. >>> >>> >>>> /* Return in next iteration if led is in one-shot mode and >>>> we are in >>>> * the final blink state so that the led is toggled each >>>> delay_on + >>>> @@ -115,6 +142,8 @@ static void set_brightness_delayed(struct >>>> work_struct *ws) >>>> if (ret == -ENOTSUPP) >>>> ret = __led_set_brightness_blocking(led_cdev, >>>> led_cdev->delayed_set_value); >>>> + __led_handle_regulator(led_cdev, led_cdev->delayed_set_value); >>>> + >>>> if (ret < 0 && >>>> /* LED HW might have been unplugged, therefore don't warn */ >>>> !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) && >>>> @@ -141,6 +170,7 @@ static void led_set_software_blink(struct >>>> led_classdev *led_cdev, >>>> /* never on - just set to off */ >>>> if (!delay_on) { >>>> led_set_brightness_nosleep(led_cdev, LED_OFF); >>>> + __led_handle_regulator(led_cdev, LED_OFF); >>>> return; >>>> } >>>> @@ -148,6 +178,7 @@ static void led_set_software_blink(struct >>>> led_classdev *led_cdev, >>>> if (!delay_off) { >>>> led_set_brightness_nosleep(led_cdev, >>>> led_cdev->blink_brightness); >>>> + __led_handle_regulator(led_cdev, led_cdev->blink_brightness); >>>> return; >>>> } >>>> @@ -256,8 +287,14 @@ void led_set_brightness_nopm(struct >>>> led_classdev *led_cdev, >>>> enum led_brightness value) >>>> { >>>> /* Use brightness_set op if available, it is guaranteed not to >>>> sleep */ >>>> - if (!__led_set_brightness(led_cdev, value)) >>>> - return; >>>> + if (!__led_set_brightness(led_cdev, value)) { >>>> + /* >>>> + * if regulator state doesn't need to be changed, that is all/ >>>> + * Otherwise delegate the change to a work queue >>>> + */ >>>> + if (!__led_need_regulator_update(led_cdev, value)) >>>> + return; >>>> + } >>>> /* If brightness setting can sleep, delegate it to a work >>>> queue task */ >>>> led_cdev->delayed_set_value = value; >>>> @@ -280,6 +317,8 @@ EXPORT_SYMBOL_GPL(led_set_brightness_nosleep); >>>> int led_set_brightness_sync(struct led_classdev *led_cdev, >>>> enum led_brightness value) >>>> { >>>> + int ret; >>>> + >>>> if (led_cdev->blink_delay_on || led_cdev->blink_delay_off) >>>> return -EBUSY; >>>> @@ -288,7 +327,15 @@ int led_set_brightness_sync(struct >>>> led_classdev *led_cdev, >>>> if (led_cdev->flags & LED_SUSPENDED) >>>> return 0; >>>> - return __led_set_brightness_blocking(led_cdev, >>>> led_cdev->brightness); >>>> + ret = __led_set_brightness_blocking(led_cdev, >>>> led_cdev->brightness); >>>> + if (ret) >>>> + return ret; >>>> + >>>> + ret = __led_handle_regulator(led_cdev, led_cdev->brightness); >>> Can't you just return here? >> ok >> >> >> thanks for the review >> >> JJ >> >>> Dan >>> >>>> + if (ret) >>>> + return ret; >>>> + >>>> + return 0; >>>> } >>>> EXPORT_SYMBOL_GPL(led_set_brightness_sync); >>>> diff --git a/include/linux/leds.h b/include/linux/leds.h >>>> index 9b2bf574a17a..bee8e3f8dddd 100644 >>>> --- a/include/linux/leds.h >>>> +++ b/include/linux/leds.h >>>> @@ -123,6 +123,10 @@ struct led_classdev { >>>> /* Ensures consistent access to the LED Flash Class device */ >>>> struct mutex led_access; >>>> + >>>> + /* regulator */ >>>> + struct regulator *regulator; >>>> + bool regulator_state; >>>> }; >>>> extern int of_led_classdev_register(struct device *parent,
On Mon, Jul 15, 2019 at 11:47:08AM +0200, Jean-Jacques Hiblot wrote: > > > > > + if (IS_ERR(led_cdev->regulator)) { > > > > > + dev_err(led_cdev->dev, "Cannot get the power supply for %s\n", > > > > > + led_cdev->name); > > > > > + device_unregister(led_cdev->dev); > > > > > + mutex_unlock(&led_cdev->led_access); > > > > > + return PTR_ERR(led_cdev->regulator); > > > > This is listed as optional in the DT doc. This appears to be required. > > > The regulator core will provide a dummy regulator if none is given in the > > > device tree. I would rather have an error in that case, but that is not how > > > it works. > > If you actively wanted to get -ENODEV back when there is no regulator > > then you can use devm_regulator_get_optional() for that. > > > > However perhaps be careful what you wish for. If you use get_optional() > > then you will have to sprinkle NULL or IS_ERR() checks everywhere. I'd > > favour using the current approach! > > Thanks for the info. I think I'll use the get_optionnal(). That will add a > bit of complexity, but it will avoid deferring some work in > led_set_brightness_nopm() when it is not needed. Makes sense, I didn't notice that it allows you to avoid deferred work. Daniel.