| Message ID | 20240913123103.21226-7-kabel@kernel.org |
|---|---|
| State | New |
| Headers | show |
| Series | Turris Omnia LED driver changes | expand |
On Fri, 13 Sep 2024, Marek Behún wrote: > Recall that on Turris Omnia, the LED controller has a global brightness > property, which allows the user to make the front LED panel dimmer. > > There is also a button on the front panel, which by default is > configured so that pressing it changes the global brightness to a lower > value (unless it is at 0%, in which case pressing the button changes the > global brightness to 100%). > > Newer versions of the MCU firmware support informing the SOC that the > brightness was changed by button press event via an interrupt. > > Now that we have the turris-omnia-mcu driver, which adds support for MCU > interrupts, add the ability to inform the userspace (via a sysfs > notification) that the global brightness was changed. > > Signed-off-by: Marek Behún <kabel@kernel.org> > --- > drivers/leds/leds-turris-omnia.c | 37 ++++++++++++++++++++++++++++++++ > 1 file changed, 37 insertions(+) > > diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c > index 82cf58fbe946..a87cdb58e476 100644 > --- a/drivers/leds/leds-turris-omnia.c > +++ b/drivers/leds/leds-turris-omnia.c > @@ -33,6 +33,7 @@ struct omnia_leds { > struct i2c_client *client; > struct mutex lock; > bool has_gamma_correction; > + struct kernfs_node *brightness_kn; Variable nomenclature should be self documenting. What is kn? Please improve this. > struct omnia_led leds[]; > }; > > @@ -357,6 +358,21 @@ static struct attribute *omnia_led_controller_attrs[] = { > }; > ATTRIBUTE_GROUPS(omnia_led_controller); > > +static irqreturn_t omnia_brightness_changed_handler(int irq, void *dev_id) Why dev_id? This appears to be driver data. ddata sounds more applicable. > +{ > + struct omnia_leds *leds = dev_id; > + > + if (unlikely(!leds->brightness_kn)) { > + leds->brightness_kn = sysfs_get_dirent(leds->client->dev.kobj.sd, "brightness"); NACK. This will sleep in IRQ context. > + if (!leds->brightness_kn) > + return IRQ_NONE; > + } > + > + sysfs_notify_dirent(leds->brightness_kn); > + > + return IRQ_HANDLED; > +} > + > static int omnia_mcu_get_features(const struct i2c_client *client) > { > struct i2c_client mcu_client = *client; > @@ -420,6 +436,14 @@ static int omnia_leds_probe(struct i2c_client *client) > "Consider upgrading MCU firmware with the omnia-mcutool utility.\n"); > } > > + if (ret & OMNIA_FEAT_BRIGHTNESS_INT) { > + ret = devm_request_any_context_irq(dev, client->irq, > + omnia_brightness_changed_handler, IRQF_ONESHOT, > + "leds-turris-omnia", leds); > + if (ret <= 0) > + return dev_err_probe(dev, ret ?: -ENXIO, "Cannot request brightness IRQ\n"); > + } > + > mutex_init(&leds->lock); > > ret = devm_led_trigger_register(dev, &omnia_hw_trigger); > @@ -442,6 +466,19 @@ static int omnia_leds_probe(struct i2c_client *client) > > static void omnia_leds_remove(struct i2c_client *client) > { > + struct omnia_leds *leds = i2c_get_clientdata(client); > + > + /* > + * We need to free the brightness IRQ here, before putting away the brightness sysfs node. > + * Otherwise devres would free the interrupt only after the sysfs node is removed, and if > + * an interrupt occurred between those two events, it would use a removed sysfs node. > + */ > + devm_free_irq(&client->dev, client->irq, leds); > + > + /* Now put away the sysfs node we got the first time the interrupt handler was called */ > + if (leds->brightness_kn) > + sysfs_put(leds->brightness_kn); > + > /* put all LEDs into default (HW triggered) mode */ > omnia_cmd_write_u8(client, OMNIA_CMD_LED_MODE, OMNIA_CMD_LED_MODE_LED(OMNIA_BOARD_LEDS)); > > -- > 2.44.2 >
diff --git a/drivers/leds/leds-turris-omnia.c b/drivers/leds/leds-turris-omnia.c index 82cf58fbe946..a87cdb58e476 100644 --- a/drivers/leds/leds-turris-omnia.c +++ b/drivers/leds/leds-turris-omnia.c @@ -33,6 +33,7 @@ struct omnia_leds { struct i2c_client *client; struct mutex lock; bool has_gamma_correction; + struct kernfs_node *brightness_kn; struct omnia_led leds[]; }; @@ -357,6 +358,21 @@ static struct attribute *omnia_led_controller_attrs[] = { }; ATTRIBUTE_GROUPS(omnia_led_controller); +static irqreturn_t omnia_brightness_changed_handler(int irq, void *dev_id) +{ + struct omnia_leds *leds = dev_id; + + if (unlikely(!leds->brightness_kn)) { + leds->brightness_kn = sysfs_get_dirent(leds->client->dev.kobj.sd, "brightness"); + if (!leds->brightness_kn) + return IRQ_NONE; + } + + sysfs_notify_dirent(leds->brightness_kn); + + return IRQ_HANDLED; +} + static int omnia_mcu_get_features(const struct i2c_client *client) { struct i2c_client mcu_client = *client; @@ -420,6 +436,14 @@ static int omnia_leds_probe(struct i2c_client *client) "Consider upgrading MCU firmware with the omnia-mcutool utility.\n"); } + if (ret & OMNIA_FEAT_BRIGHTNESS_INT) { + ret = devm_request_any_context_irq(dev, client->irq, + omnia_brightness_changed_handler, IRQF_ONESHOT, + "leds-turris-omnia", leds); + if (ret <= 0) + return dev_err_probe(dev, ret ?: -ENXIO, "Cannot request brightness IRQ\n"); + } + mutex_init(&leds->lock); ret = devm_led_trigger_register(dev, &omnia_hw_trigger); @@ -442,6 +466,19 @@ static int omnia_leds_probe(struct i2c_client *client) static void omnia_leds_remove(struct i2c_client *client) { + struct omnia_leds *leds = i2c_get_clientdata(client); + + /* + * We need to free the brightness IRQ here, before putting away the brightness sysfs node. + * Otherwise devres would free the interrupt only after the sysfs node is removed, and if + * an interrupt occurred between those two events, it would use a removed sysfs node. + */ + devm_free_irq(&client->dev, client->irq, leds); + + /* Now put away the sysfs node we got the first time the interrupt handler was called */ + if (leds->brightness_kn) + sysfs_put(leds->brightness_kn); + /* put all LEDs into default (HW triggered) mode */ omnia_cmd_write_u8(client, OMNIA_CMD_LED_MODE, OMNIA_CMD_LED_MODE_LED(OMNIA_BOARD_LEDS));
Recall that on Turris Omnia, the LED controller has a global brightness property, which allows the user to make the front LED panel dimmer. There is also a button on the front panel, which by default is configured so that pressing it changes the global brightness to a lower value (unless it is at 0%, in which case pressing the button changes the global brightness to 100%). Newer versions of the MCU firmware support informing the SOC that the brightness was changed by button press event via an interrupt. Now that we have the turris-omnia-mcu driver, which adds support for MCU interrupts, add the ability to inform the userspace (via a sysfs notification) that the global brightness was changed. Signed-off-by: Marek Behún <kabel@kernel.org> --- drivers/leds/leds-turris-omnia.c | 37 ++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+)