From b18c1ad685d9a6af5189d4cc037a653270a07b4c Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Mon, 18 Oct 2021 15:17:25 +0300 Subject: i2c: Allow an ACPI driver to manage the device's power state during probe 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. Add a field called "flags" into struct i2c_driver for driver flags, and a flag I2C_DRV_ACPI_WAIVE_D0_PROBE to tell a driver supports probe in ACPI D states other than 0. Signed-off-by: Sakari Ailus Reviewed-by: Tomasz Figa Acked-by: Wolfram Sang Signed-off-by: Rafael J. Wysocki --- include/linux/i2c.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include/linux') diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 2ce3efbe9198..16119ac1aa97 100644 --- a/include/linux/i2c.h +++ b/include/linux/i2c.h @@ -11,6 +11,7 @@ #define _LINUX_I2C_H #include /* for acpi_handle */ +#include #include #include /* for struct device */ #include /* for completion */ @@ -222,6 +223,15 @@ enum i2c_alert_protocol { I2C_PROTOCOL_SMBUS_HOST_NOTIFY, }; +/** + * enum i2c_driver_flags - Flags for an I2C device driver + * + * @I2C_DRV_ACPI_WAIVE_D0_PROBE: Don't put the device in D0 state for probe + */ +enum i2c_driver_flags { + I2C_DRV_ACPI_WAIVE_D0_PROBE = BIT(0), +}; + /** * struct i2c_driver - represent an I2C device driver * @class: What kind of i2c device we instantiate (for detect) @@ -236,6 +246,7 @@ enum i2c_alert_protocol { * @detect: Callback for device detection * @address_list: The I2C addresses to probe (for detect) * @clients: List of detected clients we created (for i2c-core use only) + * @flags: A bitmask of flags defined in &enum i2c_driver_flags * * 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. @@ -294,6 +305,8 @@ struct i2c_driver { int (*detect)(struct i2c_client *client, struct i2c_board_info *info); const unsigned short *address_list; struct list_head clients; + + u32 flags; }; #define to_i2c_driver(d) container_of(d, struct i2c_driver, driver) @@ -1015,6 +1028,7 @@ u32 i2c_acpi_find_bus_speed(struct device *dev); struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, struct i2c_board_info *info); struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle); +bool i2c_acpi_waive_d0_probe(struct device *dev); #else static inline bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, struct acpi_resource_i2c_serialbus **i2c) @@ -1038,6 +1052,10 @@ static inline struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle ha { return NULL; } +static inline bool i2c_acpi_waive_d0_probe(struct device *dev) +{ + return false; +} #endif /* CONFIG_ACPI */ #endif /* _LINUX_I2C_H */ -- cgit v1.2.3 From b82a7df4a7f3841896aaec1ad81e654bc87b5989 Mon Sep 17 00:00:00 2001 From: Sakari Ailus Date: Mon, 18 Oct 2021 15:17:27 +0300 Subject: ACPI: Add a convenience function to tell a device is in D0 state Add a convenience function to tell whether a device is in D0 state, primarily for use in drivers' probe or remove functions on busses where the custom is to power on the device for the duration of both. Returns false on non-ACPI systems. Suggested-by: Mika Westerberg Signed-off-by: Sakari Ailus Reviewed-by: Tomasz Figa Signed-off-by: Rafael J. Wysocki --- include/linux/acpi.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux') diff --git a/include/linux/acpi.h b/include/linux/acpi.h index fbc2146050a4..df70fc27afd7 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1016,6 +1016,7 @@ int acpi_subsys_runtime_suspend(struct device *dev); int acpi_subsys_runtime_resume(struct device *dev); int acpi_dev_pm_attach(struct device *dev, bool power_on); bool acpi_storage_d3(struct device *dev); +bool acpi_dev_state_d0(struct device *dev); #else static inline int acpi_subsys_runtime_suspend(struct device *dev) { return 0; } static inline int acpi_subsys_runtime_resume(struct device *dev) { return 0; } @@ -1027,6 +1028,10 @@ static inline bool acpi_storage_d3(struct device *dev) { return false; } +static inline bool acpi_dev_state_d0(struct device *dev) +{ + return true; +} #endif #if defined(CONFIG_ACPI) && defined(CONFIG_PM_SLEEP) -- cgit v1.2.3