* [PATCH v2 0/2] leds: Add control of the voltage/current regulator to the LED core
@ 2019-07-15 15:56 Jean-Jacques Hiblot
2019-07-15 15:56 ` [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property Jean-Jacques Hiblot
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
0 siblings, 2 replies; 11+ messages in thread
From: Jean-Jacques Hiblot @ 2019-07-15 15:56 UTC (permalink / raw)
To: jacek.anaszewski, pavel, robh+dt, mark.rutland, daniel.thompson
Cc: dmurphy, linux-leds, linux-kernel, devicetree, Jean-Jacques Hiblot
This series makes it possible for the LED core to manage the power supply
of a LED. It uses the regulator API to disable/enable the power if when the
LED is turned on/off.
This is especially useful in situations where the LED driver/controller is
not supplying the power.
changes in v2:
- use devm_regulator_get_optional() to avoid using the dummy regulator and do
some unnecessary work
Jean-Jacques Hiblot (2):
dt-bindings: leds: document the "power-supply" property
leds: Add control of the voltage/current regulator to the LED core
.../devicetree/bindings/leds/common.txt | 6 +++
drivers/leds/led-class.c | 15 ++++++
drivers/leds/led-core.c | 50 +++++++++++++++++--
drivers/leds/leds.h | 1 +
include/linux/leds.h | 4 ++
5 files changed, 73 insertions(+), 3 deletions(-)
--
2.17.1
^ permalink raw reply [flat|nested] 11+ messages in thread
* [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property
2019-07-15 15:56 [PATCH v2 0/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
@ 2019-07-15 15:56 ` Jean-Jacques Hiblot
2019-07-15 18:52 ` Dan Murphy
2019-08-19 11:31 ` Pavel Machek
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
1 sibling, 2 replies; 11+ messages in thread
From: Jean-Jacques Hiblot @ 2019-07-15 15:56 UTC (permalink / raw)
To: jacek.anaszewski, pavel, robh+dt, mark.rutland, daniel.thompson
Cc: dmurphy, linux-leds, linux-kernel, devicetree, Jean-Jacques Hiblot
Most of the LEDs are powered by a voltage/current regulator. Describing it
in the device-tree makes it possible for the LED core to enable/disable it
when needed.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
---
Documentation/devicetree/bindings/leds/common.txt | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/Documentation/devicetree/bindings/leds/common.txt b/Documentation/devicetree/bindings/leds/common.txt
index 70876ac11367..539e124b1457 100644
--- a/Documentation/devicetree/bindings/leds/common.txt
+++ b/Documentation/devicetree/bindings/leds/common.txt
@@ -61,6 +61,11 @@ Optional properties for child nodes:
- panic-indicator : This property specifies that the LED should be used,
if at all possible, as a panic indicator.
+- power-supply : A voltage/current regulator used to to power the LED. When a
+ LED is turned off, the LED core disable its regulator. The
+ same regulator can power many LED (or other) devices. It is
+ turned off only when all of its users disabled it.
+
- trigger-sources : List of devices which should be used as a source triggering
this LED activity. Some LEDs can be related to a specific
device and should somehow indicate its state. E.g. USB 2.0
@@ -106,6 +111,7 @@ gpio-leds {
label = "Status";
linux,default-trigger = "heartbeat";
gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
+ power-supply = <&led_regulator>;
};
usb {
--
2.17.1
^ permalink raw reply related [flat|nested] 11+ messages in thread
* [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-15 15:56 [PATCH v2 0/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-15 15:56 ` [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property Jean-Jacques Hiblot
@ 2019-07-15 15:56 ` Jean-Jacques Hiblot
2019-07-15 18:59 ` Dan Murphy
` (2 more replies)
1 sibling, 3 replies; 11+ messages in thread
From: Jean-Jacques Hiblot @ 2019-07-15 15:56 UTC (permalink / raw)
To: jacek.anaszewski, pavel, robh+dt, mark.rutland, daniel.thompson
Cc: dmurphy, linux-leds, linux-kernel, devicetree, Jean-Jacques Hiblot
A LED is usually powered by a voltage/current regulator. 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 | 15 ++++++++++++
drivers/leds/led-core.c | 50 +++++++++++++++++++++++++++++++++++++---
drivers/leds/leds.h | 1 +
include/linux/leds.h | 4 ++++
4 files changed, 67 insertions(+), 3 deletions(-)
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index 4793e77808e2..cadd43c30d50 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -253,6 +253,7 @@ int of_led_classdev_register(struct device *parent, struct device_node *np,
{
char name[LED_MAX_NAME_SIZE];
int ret;
+ struct regulator *regulator;
ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
if (ret < 0)
@@ -272,6 +273,20 @@ 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));
+ regulator = devm_regulator_get_optional(led_cdev->dev, "power");
+ if (IS_ERR(regulator)) {
+ if (PTR_ERR(regulator) != -ENODEV) {
+ 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(regulator);
+ }
+ led_cdev->regulator = NULL;
+ } else {
+ led_cdev->regulator = regulator;
+ }
+
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..a12b880b0a2f 100644
--- a/drivers/leds/led-core.c
+++ b/drivers/leds/led-core.c
@@ -23,6 +23,33 @@ 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_state = (brightness != LED_OFF);
+
+ return led_cdev->regulator && led_cdev->regulator_state != new_state;
+}
+
+static int __led_handle_regulator(struct led_classdev *led_cdev,
+ int brightness)
+{
+ int rc;
+
+ if (__led_need_regulator_update(led_cdev, brightness)) {
+
+ if (brightness != LED_OFF)
+ rc = regulator_enable(led_cdev->regulator);
+ else
+ rc = regulator_disable(led_cdev->regulator);
+ if (rc)
+ return rc;
+
+ 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 +107,7 @@ static void led_timer_function(struct timer_list *t)
}
led_set_brightness_nosleep(led_cdev, brightness);
+ __led_handle_regulator(led_cdev, brightness);
/* 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 +143,8 @@ 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 +171,7 @@ 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 +179,7 @@ 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 +288,14 @@ 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 +318,8 @@ 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 +328,11 @@ 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;
+
+ return __led_handle_regulator(led_cdev, led_cdev->brightness);
}
EXPORT_SYMBOL_GPL(led_set_brightness_sync);
diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
index 47b229469069..5aa5c038bd38 100644
--- a/drivers/leds/leds.h
+++ b/drivers/leds/leds.h
@@ -11,6 +11,7 @@
#include <linux/rwsem.h>
#include <linux/leds.h>
+#include <linux/regulator/consumer.h>
static inline int led_get_brightness(struct led_classdev *led_cdev)
{
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,
--
2.17.1
^ permalink raw reply related [flat|nested] 11+ messages in thread
* Re: [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property
2019-07-15 15:56 ` [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property Jean-Jacques Hiblot
@ 2019-07-15 18:52 ` Dan Murphy
2019-08-19 11:31 ` Pavel Machek
1 sibling, 0 replies; 11+ messages in thread
From: Dan Murphy @ 2019-07-15 18:52 UTC (permalink / raw)
To: Jean-Jacques Hiblot, jacek.anaszewski, pavel, robh+dt,
mark.rutland, daniel.thompson
Cc: linux-leds, linux-kernel, devicetree
JJ
On 7/15/19 10:56 AM, Jean-Jacques Hiblot wrote:
> Most of the LEDs are powered by a voltage/current regulator. Describing it
> in the device-tree makes it possible for the LED core to enable/disable it
> when needed.
>
> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
> ---
> Documentation/devicetree/bindings/leds/common.txt | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/leds/common.txt b/Documentation/devicetree/bindings/leds/common.txt
> index 70876ac11367..539e124b1457 100644
> --- a/Documentation/devicetree/bindings/leds/common.txt
> +++ b/Documentation/devicetree/bindings/leds/common.txt
> @@ -61,6 +61,11 @@ Optional properties for child nodes:
> - panic-indicator : This property specifies that the LED should be used,
> if at all possible, as a panic indicator.
>
> +- power-supply : A voltage/current regulator used to to power the LED. When a
Is the phandle to a voltage/current regulator used to to power the LED
> + LED is turned off, the LED core disable its regulator. The
The regulator is only disabled if it is the only consumer and/or the
number of users = 0.
> + same regulator can power many LED (or other) devices. It is
> + turned off only when all of its users disabled it.
> +
> - trigger-sources : List of devices which should be used as a source triggering
> this LED activity. Some LEDs can be related to a specific
> device and should somehow indicate its state. E.g. USB 2.0
> @@ -106,6 +111,7 @@ gpio-leds {
> label = "Status";
> linux,default-trigger = "heartbeat";
> gpios = <&gpio0 0 GPIO_ACTIVE_HIGH>;
> + power-supply = <&led_regulator>;
> };
>
> usb {
Reviewed-by: Dan Murphy <dmurphy@ti.com>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
@ 2019-07-15 18:59 ` Dan Murphy
2019-07-17 13:14 ` Jean-Jacques Hiblot
2019-07-15 20:42 ` Jacek Anaszewski
2019-07-16 10:50 ` Daniel Thompson
2 siblings, 1 reply; 11+ messages in thread
From: Dan Murphy @ 2019-07-15 18:59 UTC (permalink / raw)
To: Jean-Jacques Hiblot, jacek.anaszewski, pavel, robh+dt,
mark.rutland, daniel.thompson
Cc: linux-leds, linux-kernel, devicetree
JJ
On 7/15/19 10:56 AM, Jean-Jacques Hiblot wrote:
> A LED is usually powered by a voltage/current regulator. Let the LED core
> know about it. This allows the LED core to turn on or off the power supply
> as needed.
This allows the LED core to turn on or off managed power supplies.
>
> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
> ---
> drivers/leds/led-class.c | 15 ++++++++++++
> drivers/leds/led-core.c | 50 +++++++++++++++++++++++++++++++++++++---
> drivers/leds/leds.h | 1 +
> include/linux/leds.h | 4 ++++
> 4 files changed, 67 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
> index 4793e77808e2..cadd43c30d50 100644
> --- a/drivers/leds/led-class.c
> +++ b/drivers/leds/led-class.c
> @@ -253,6 +253,7 @@ int of_led_classdev_register(struct device *parent, struct device_node *np,
> {
> char name[LED_MAX_NAME_SIZE];
> int ret;
> + struct regulator *regulator;
>
> ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
> if (ret < 0)
> @@ -272,6 +273,20 @@ 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));
>
> + regulator = devm_regulator_get_optional(led_cdev->dev, "power");
Store the regulator in led_cdev->regulator and drop the else case below.
> + if (IS_ERR(regulator)) {
> + if (PTR_ERR(regulator) != -ENODEV) {
> + 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(regulator);
> + }
> + led_cdev->regulator = NULL;
> + } else {
> + led_cdev->regulator = regulator;
> + }
> +
> 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..a12b880b0a2f 100644
> --- a/drivers/leds/led-core.c
> +++ b/drivers/leds/led-core.c
> @@ -23,6 +23,33 @@ 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_state = (brightness != LED_OFF);
> +
> + return led_cdev->regulator && led_cdev->regulator_state != new_state;
> +}
> +
> +static int __led_handle_regulator(struct led_classdev *led_cdev,
> + int brightness)
> +{
> + int rc;
Should there be a check for the regulator pointer.
If (!led_cdev->regulator)
return 0;
Otherwise
Reviewed-by: Dan Murphy <dmurphy@ti.com>
<snip>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-15 18:59 ` Dan Murphy
@ 2019-07-15 20:42 ` Jacek Anaszewski
2019-07-17 13:23 ` Jean-Jacques Hiblot
2019-07-16 10:50 ` Daniel Thompson
2 siblings, 1 reply; 11+ messages in thread
From: Jacek Anaszewski @ 2019-07-15 20:42 UTC (permalink / raw)
To: Jean-Jacques Hiblot, pavel, robh+dt, mark.rutland, daniel.thompson
Cc: dmurphy, linux-leds, linux-kernel, devicetree
Hi Jean,
Thank you for the patch.
I have one issue. Please refer below.
On 7/15/19 5:56 PM, Jean-Jacques Hiblot wrote:
> A LED is usually powered by a voltage/current regulator. 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 | 15 ++++++++++++
> drivers/leds/led-core.c | 50 +++++++++++++++++++++++++++++++++++++---
> drivers/leds/leds.h | 1 +
> include/linux/leds.h | 4 ++++
> 4 files changed, 67 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
> index 4793e77808e2..cadd43c30d50 100644
> --- a/drivers/leds/led-class.c
> +++ b/drivers/leds/led-class.c
> @@ -253,6 +253,7 @@ int of_led_classdev_register(struct device *parent, struct device_node *np,
> {
> char name[LED_MAX_NAME_SIZE];
> int ret;
> + struct regulator *regulator;
>
> ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
> if (ret < 0)
> @@ -272,6 +273,20 @@ 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));
>
> + regulator = devm_regulator_get_optional(led_cdev->dev, "power");
> + if (IS_ERR(regulator)) {
> + if (PTR_ERR(regulator) != -ENODEV) {
> + 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(regulator);
> + }
> + led_cdev->regulator = NULL;
> + } else {
> + led_cdev->regulator = regulator;
> + }
> +
> 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..a12b880b0a2f 100644
> --- a/drivers/leds/led-core.c
> +++ b/drivers/leds/led-core.c
> @@ -23,6 +23,33 @@ 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_state = (brightness != LED_OFF);
> +
> + return led_cdev->regulator && led_cdev->regulator_state != new_state;
> +}
> +
> +static int __led_handle_regulator(struct led_classdev *led_cdev,
> + int brightness)
> +{
> + int rc;
> +
> + if (__led_need_regulator_update(led_cdev, brightness)) {
> +
> + if (brightness != LED_OFF)
> + rc = regulator_enable(led_cdev->regulator);
> + else
> + rc = regulator_disable(led_cdev->regulator);
> + if (rc)
> + return rc;
> +
> + 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 +107,7 @@ static void led_timer_function(struct timer_list *t)
> }
>
> led_set_brightness_nosleep(led_cdev, brightness);
> + __led_handle_regulator(led_cdev, brightness);
This cannot be called from atomic context since regulator_enable/disable
use mutex beneath, that can sleep on contention. Therefore this call
has to be made in two places instead:
__led_set_brightness()
__led_set_brightness_blocking()
>
> /* 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 +143,8 @@ 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 +171,7 @@ 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 +179,7 @@ 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 +288,14 @@ 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 +318,8 @@ 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 +328,11 @@ 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;
> +
> + return __led_handle_regulator(led_cdev, led_cdev->brightness);
> }
> EXPORT_SYMBOL_GPL(led_set_brightness_sync);
>
> diff --git a/drivers/leds/leds.h b/drivers/leds/leds.h
> index 47b229469069..5aa5c038bd38 100644
> --- a/drivers/leds/leds.h
> +++ b/drivers/leds/leds.h
> @@ -11,6 +11,7 @@
>
> #include <linux/rwsem.h>
> #include <linux/leds.h>
> +#include <linux/regulator/consumer.h>
>
> static inline int led_get_brightness(struct led_classdev *led_cdev)
> {
> 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,
>
--
Best regards,
Jacek Anaszewski
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-15 18:59 ` Dan Murphy
2019-07-15 20:42 ` Jacek Anaszewski
@ 2019-07-16 10:50 ` Daniel Thompson
2019-07-17 13:47 ` Jean-Jacques Hiblot
2 siblings, 1 reply; 11+ messages in thread
From: Daniel Thompson @ 2019-07-16 10:50 UTC (permalink / raw)
To: Jean-Jacques Hiblot
Cc: jacek.anaszewski, pavel, robh+dt, mark.rutland, dmurphy,
linux-leds, linux-kernel, devicetree
On Mon, Jul 15, 2019 at 05:56:57PM +0200, Jean-Jacques Hiblot wrote:
> A LED is usually powered by a voltage/current regulator. Let the LED core
This is almost certainly nitpicking but since there's enough other
review comments that you will have to respin anyway ;-)
Is an LED really "usually powered by a voltage/current regulator"? Some
LEDs have a software controlled power supply but I'm not sure it is
the usual case.
Likewise its a little confusing to be talking about LEDs with an
external current regulator since, although that is possible, it is also
one the main features provided by LED driver chips.
Daniel.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-15 18:59 ` Dan Murphy
@ 2019-07-17 13:14 ` Jean-Jacques Hiblot
0 siblings, 0 replies; 11+ messages in thread
From: Jean-Jacques Hiblot @ 2019-07-17 13:14 UTC (permalink / raw)
To: Dan Murphy, jacek.anaszewski, pavel, robh+dt, mark.rutland,
daniel.thompson
Cc: linux-leds, linux-kernel, devicetree
Hi Dan,
On 15/07/2019 20:59, Dan Murphy wrote:
> JJ
>
> On 7/15/19 10:56 AM, Jean-Jacques Hiblot wrote:
>> A LED is usually powered by a voltage/current regulator. Let the LED
>> core
>> know about it. This allows the LED core to turn on or off the power
>> supply
>> as needed.
>
> This allows the LED core to turn on or off managed power supplies.
>
>
>>
>> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
>> ---
>> 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..a12b880b0a2f 100644
>> --- a/drivers/leds/led-core.c
>> +++ b/drivers/leds/led-core.c
>> @@ -23,6 +23,33 @@ 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_state = (brightness != LED_OFF);
>> +
>> + return led_cdev->regulator && led_cdev->regulator_state !=
>> new_state;
>> +}
>> +
>> +static int __led_handle_regulator(struct led_classdev *led_cdev,
>> + int brightness)
>> +{
>> + int rc;
>
> Should there be a check for the regulator pointer.
>
> If (!led_cdev->regulator)
>
> return 0;
Not required because __led_need_regulator_update() returns false if
led_cdev->regulator is NULL.
Thanks for the review
JJ
>
>
> Otherwise
>
> Reviewed-by: Dan Murphy <dmurphy@ti.com>
>
> <snip>
>
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-15 20:42 ` Jacek Anaszewski
@ 2019-07-17 13:23 ` Jean-Jacques Hiblot
0 siblings, 0 replies; 11+ messages in thread
From: Jean-Jacques Hiblot @ 2019-07-17 13:23 UTC (permalink / raw)
To: Jacek Anaszewski, pavel, mark.rutland, daniel.thompson
Cc: dmurphy, linux-leds, linux-kernel
Hi Jacek,
On 15/07/2019 22:42, Jacek Anaszewski wrote:
> @@ -80,6 +107,7 @@ static void led_timer_function(struct timer_list *t)
> }
>
> led_set_brightness_nosleep(led_cdev, brightness);
> + __led_handle_regulator(led_cdev, brightness);
> This cannot be called from atomic context since regulator_enable/disable
> use mutex beneath, that can sleep on contention. Therefore this call
> has to be made in two places instead:
>
> __led_set_brightness()
> __led_set_brightness_blocking()
Thanks. I'll fix this in v3.
JJ
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
2019-07-16 10:50 ` Daniel Thompson
@ 2019-07-17 13:47 ` Jean-Jacques Hiblot
0 siblings, 0 replies; 11+ messages in thread
From: Jean-Jacques Hiblot @ 2019-07-17 13:47 UTC (permalink / raw)
To: Daniel Thompson
Cc: jacek.anaszewski, pavel, robh+dt, mark.rutland, dmurphy,
linux-leds, linux-kernel, devicetree
On 16/07/2019 12:50, Daniel Thompson wrote:
> On Mon, Jul 15, 2019 at 05:56:57PM +0200, Jean-Jacques Hiblot wrote:
>> A LED is usually powered by a voltage/current regulator. Let the LED core
> This is almost certainly nitpicking but since there's enough other
> review comments that you will have to respin anyway ;-)
No problems. comments are welcome.
> Is an LED really "usually powered by a voltage/current regulator"? Some
> LEDs have a software controlled power supply but I'm not sure it is
> the usual case.
True. I'll reword this.
> Likewise its a little confusing to be talking about LEDs with an
> external current regulator since, although that is possible, it is also
> one the main features provided by LED driver chips.
In my experience LED drivers are quite often current sinks. In that case
the power is provided externally, and sometimes by a managed regulator.
Thanks,
JJ
>
> Daniel.
^ permalink raw reply [flat|nested] 11+ messages in thread
* Re: [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property
2019-07-15 15:56 ` [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property Jean-Jacques Hiblot
2019-07-15 18:52 ` Dan Murphy
@ 2019-08-19 11:31 ` Pavel Machek
1 sibling, 0 replies; 11+ messages in thread
From: Pavel Machek @ 2019-08-19 11:31 UTC (permalink / raw)
To: Jean-Jacques Hiblot
Cc: jacek.anaszewski, robh+dt, mark.rutland, daniel.thompson,
dmurphy, linux-leds, linux-kernel, devicetree
[-- Attachment #1: Type: text/plain, Size: 470 bytes --]
On Mon 2019-07-15 17:56:56, Jean-Jacques Hiblot wrote:
> Most of the LEDs are powered by a voltage/current regulator. Describing it
> in the device-tree makes it possible for the LED core to enable/disable it
> when needed.
>
> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
^ permalink raw reply [flat|nested] 11+ messages in thread
end of thread, other threads:[~2019-08-19 11:31 UTC | newest]
Thread overview: 11+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-07-15 15:56 [PATCH v2 0/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-15 15:56 ` [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property Jean-Jacques Hiblot
2019-07-15 18:52 ` Dan Murphy
2019-08-19 11:31 ` Pavel Machek
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-15 18:59 ` Dan Murphy
2019-07-17 13:14 ` Jean-Jacques Hiblot
2019-07-15 20:42 ` Jacek Anaszewski
2019-07-17 13:23 ` Jean-Jacques Hiblot
2019-07-16 10:50 ` Daniel Thompson
2019-07-17 13:47 ` Jean-Jacques Hiblot
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