| Message ID | 20200121134157.20396-2-sakari.ailus@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Support running driver's probe for a device powered off | expand |
wt., 21 sty 2020 o 14:41 Sakari Ailus <sakari.ailus@linux.intel.com> napisał(a): > > Enable drivers to tell ACPI that there's no need to power on a device for > probe. Drivers should still perform this by themselves if there's a need > to. In some cases powering on the device during probe is undesirable, and > this change enables a driver to choose what fits best for it. > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > --- > drivers/i2c/i2c-core-base.c | 15 ++++++++++++--- > include/linux/i2c.h | 3 +++ > 2 files changed, 15 insertions(+), 3 deletions(-) > > diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c > index 9f8dcd3f83850..7bf1699c9044d 100644 > --- a/drivers/i2c/i2c-core-base.c > +++ b/drivers/i2c/i2c-core-base.c > @@ -303,6 +303,14 @@ static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) > return irq > 0 ? irq : -ENXIO; > } > > +static bool probe_low_power(struct device *dev) > +{ > + struct i2c_driver *driver = to_i2c_driver(dev->driver); > + > + return driver->probe_low_power && > + device_property_present(dev, "probe-low-power"); > +} > + > static int i2c_device_probe(struct device *dev) > { > struct i2c_client *client = i2c_verify_client(dev); > @@ -375,7 +383,8 @@ static int i2c_device_probe(struct device *dev) > if (status < 0) > goto err_clear_wakeup_irq; > > - status = dev_pm_domain_attach(&client->dev, true); > + status = dev_pm_domain_attach(&client->dev, > + !probe_low_power(&client->dev)); > if (status) > goto err_clear_wakeup_irq; > > @@ -397,7 +406,7 @@ static int i2c_device_probe(struct device *dev) > return 0; > > err_detach_pm_domain: > - dev_pm_domain_detach(&client->dev, true); > + dev_pm_domain_detach(&client->dev, !probe_low_power(&client->dev)); > err_clear_wakeup_irq: > dev_pm_clear_wake_irq(&client->dev); > device_init_wakeup(&client->dev, false); > @@ -419,7 +428,7 @@ static int i2c_device_remove(struct device *dev) > status = driver->remove(client); > } > > - dev_pm_domain_detach(&client->dev, true); > + dev_pm_domain_detach(&client->dev, !probe_low_power(&client->dev)); > > dev_pm_clear_wake_irq(&client->dev); > device_init_wakeup(&client->dev, false); > diff --git a/include/linux/i2c.h b/include/linux/i2c.h > index 582ef05ec07ed..6d0d6af393c56 100644 > --- a/include/linux/i2c.h > +++ b/include/linux/i2c.h > @@ -229,6 +229,8 @@ enum i2c_alert_protocol { > * @address_list: The I2C addresses to probe (for detect) > * @clients: List of detected clients we created (for i2c-core use only) > * @disable_i2c_core_irq_mapping: Tell the i2c-core to not do irq-mapping > + * @probe_low_power: Let the driver manage the device's power state > + * during probe and remove. > * > * The driver.owner field should be set to the module owner of this driver. > * The driver.name field should be set to the name of this driver. > @@ -289,6 +291,7 @@ struct i2c_driver { > struct list_head clients; > > bool disable_i2c_core_irq_mapping; > + bool probe_low_power; I don't see any users of disable_i2c_core_irq_mapping in current mainline. Maybe instead of adding another 1-byte boolean for every such property, let's just use the fact that this struct will have at least an alignment of 32-bits anyway and merge the two into an int field called 'flags' so that we can extend it in the future if needed? The name 'probe_low_power' is misleading to me too. It makes me think it's the default state for some reason. It should be something like 'allow_low_power_probe'. Bartosz > }; > #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) > > -- > 2.20.1 >
Hi Bartosz, On Wed, Jan 29, 2020 at 02:54:20PM +0100, Bartosz Golaszewski wrote: > wt., 21 sty 2020 o 14:41 Sakari Ailus <sakari.ailus@linux.intel.com> napisał(a): > > > > Enable drivers to tell ACPI that there's no need to power on a device for > > probe. Drivers should still perform this by themselves if there's a need > > to. In some cases powering on the device during probe is undesirable, and > > this change enables a driver to choose what fits best for it. > > > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > > --- > > drivers/i2c/i2c-core-base.c | 15 ++++++++++++--- > > include/linux/i2c.h | 3 +++ > > 2 files changed, 15 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c > > index 9f8dcd3f83850..7bf1699c9044d 100644 > > --- a/drivers/i2c/i2c-core-base.c > > +++ b/drivers/i2c/i2c-core-base.c > > @@ -303,6 +303,14 @@ static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) > > return irq > 0 ? irq : -ENXIO; > > } > > > > +static bool probe_low_power(struct device *dev) > > +{ > > + struct i2c_driver *driver = to_i2c_driver(dev->driver); > > + > > + return driver->probe_low_power && > > + device_property_present(dev, "probe-low-power"); > > +} > > + > > static int i2c_device_probe(struct device *dev) > > { > > struct i2c_client *client = i2c_verify_client(dev); > > @@ -375,7 +383,8 @@ static int i2c_device_probe(struct device *dev) > > if (status < 0) > > goto err_clear_wakeup_irq; > > > > - status = dev_pm_domain_attach(&client->dev, true); > > + status = dev_pm_domain_attach(&client->dev, > > + !probe_low_power(&client->dev)); > > if (status) > > goto err_clear_wakeup_irq; > > > > @@ -397,7 +406,7 @@ static int i2c_device_probe(struct device *dev) > > return 0; > > > > err_detach_pm_domain: > > - dev_pm_domain_detach(&client->dev, true); > > + dev_pm_domain_detach(&client->dev, !probe_low_power(&client->dev)); > > err_clear_wakeup_irq: > > dev_pm_clear_wake_irq(&client->dev); > > device_init_wakeup(&client->dev, false); > > @@ -419,7 +428,7 @@ static int i2c_device_remove(struct device *dev) > > status = driver->remove(client); > > } > > > > - dev_pm_domain_detach(&client->dev, true); > > + dev_pm_domain_detach(&client->dev, !probe_low_power(&client->dev)); > > > > dev_pm_clear_wake_irq(&client->dev); > > device_init_wakeup(&client->dev, false); > > diff --git a/include/linux/i2c.h b/include/linux/i2c.h > > index 582ef05ec07ed..6d0d6af393c56 100644 > > --- a/include/linux/i2c.h > > +++ b/include/linux/i2c.h > > @@ -229,6 +229,8 @@ enum i2c_alert_protocol { > > * @address_list: The I2C addresses to probe (for detect) > > * @clients: List of detected clients we created (for i2c-core use only) > > * @disable_i2c_core_irq_mapping: Tell the i2c-core to not do irq-mapping > > + * @probe_low_power: Let the driver manage the device's power state > > + * during probe and remove. > > * > > * The driver.owner field should be set to the module owner of this driver. > > * The driver.name field should be set to the name of this driver. > > @@ -289,6 +291,7 @@ struct i2c_driver { > > struct list_head clients; > > > > bool disable_i2c_core_irq_mapping; > > + bool probe_low_power; > > I don't see any users of disable_i2c_core_irq_mapping in current > mainline. Maybe instead of adding another 1-byte boolean for every > such property, let's just use the fact that this struct will have at > least an alignment of 32-bits anyway and merge the two into an int > field called 'flags' so that we can extend it in the future if needed? > > The name 'probe_low_power' is misleading to me too. It makes me think > it's the default state for some reason. It should be something like > 'allow_low_power_probe'. Ah, got around reading this one after sending the previous mail. Sounds reasonable. I'll address both in v5.
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 9f8dcd3f83850..7bf1699c9044d 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -303,6 +303,14 @@ static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) return irq > 0 ? irq : -ENXIO; } +static bool probe_low_power(struct device *dev) +{ + struct i2c_driver *driver = to_i2c_driver(dev->driver); + + return driver->probe_low_power && + device_property_present(dev, "probe-low-power"); +} + static int i2c_device_probe(struct device *dev) { struct i2c_client *client = i2c_verify_client(dev); @@ -375,7 +383,8 @@ static int i2c_device_probe(struct device *dev) if (status < 0) goto err_clear_wakeup_irq; - status = dev_pm_domain_attach(&client->dev, true); + status = dev_pm_domain_attach(&client->dev, + !probe_low_power(&client->dev)); if (status) goto err_clear_wakeup_irq; @@ -397,7 +406,7 @@ static int i2c_device_probe(struct device *dev) return 0; err_detach_pm_domain: - dev_pm_domain_detach(&client->dev, true); + dev_pm_domain_detach(&client->dev, !probe_low_power(&client->dev)); err_clear_wakeup_irq: dev_pm_clear_wake_irq(&client->dev); device_init_wakeup(&client->dev, false); @@ -419,7 +428,7 @@ static int i2c_device_remove(struct device *dev) status = driver->remove(client); } - dev_pm_domain_detach(&client->dev, true); + dev_pm_domain_detach(&client->dev, !probe_low_power(&client->dev)); dev_pm_clear_wake_irq(&client->dev); device_init_wakeup(&client->dev, false); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 582ef05ec07ed..6d0d6af393c56 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -229,6 +229,8 @@ enum i2c_alert_protocol { * @address_list: The I2C addresses to probe (for detect) * @clients: List of detected clients we created (for i2c-core use only) * @disable_i2c_core_irq_mapping: Tell the i2c-core to not do irq-mapping + * @probe_low_power: Let the driver manage the device's power state + * during probe and remove. * * The driver.owner field should be set to the module owner of this driver. * The driver.name field should be set to the name of this driver. @@ -289,6 +291,7 @@ struct i2c_driver { struct list_head clients; bool disable_i2c_core_irq_mapping; + bool probe_low_power; }; #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver)
Enable drivers to tell ACPI that there's no need to power on a device for probe. Drivers should still perform this by themselves if there's a need to. In some cases powering on the device during probe is undesirable, and this change enables a driver to choose what fits best for it. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> --- drivers/i2c/i2c-core-base.c | 15 ++++++++++++--- include/linux/i2c.h | 3 +++ 2 files changed, 15 insertions(+), 3 deletions(-)