[PATCH 1/3] power_supply: Introduce generic psy charging driver
The Power Supply charging driver connects multiple subsystems to do charging in a generic way. The subsystems involves power_supply, thermal and battery communication subsystems (1wire). With this the charging is handled in a generic way. The driver makes use of different new features - Battery Identification interfaces, pluggable charging algorithms, charger cable arbitrations etc. The patch also introduces generic interface for charger cable notifications. Charger cable events and capabilities can be notified using the generic power_supply_notifier chain. Overall this driver removes the charging logic out of the charger chip driver and the charger chip driver can just listen to the request from the power supply charging driver to set the charger properties. This can be implemented by exposing get_property and set_property callbacks. Signed-off-by: Jenny TC --- Documentation/power/power_supply_charger.txt | 349 drivers/power/Kconfig|8 + drivers/power/Makefile |1 + drivers/power/power_supply_charger.c | 1206 ++ drivers/power/power_supply_charger.h | 224 + drivers/power/power_supply_core.c|3 + include/linux/power/power_supply_charger.h | 308 +++ include/linux/power_supply.h | 161 8 files changed, 2260 insertions(+) create mode 100644 Documentation/power/power_supply_charger.txt create mode 100644 drivers/power/power_supply_charger.c create mode 100644 drivers/power/power_supply_charger.h create mode 100644 include/linux/power/power_supply_charger.h diff --git a/Documentation/power/power_supply_charger.txt b/Documentation/power/power_supply_charger.txt new file mode 100644 index 000..6ae59ea --- /dev/null +++ b/Documentation/power/power_supply_charger.txt @@ -0,0 +1,349 @@ +1. Introduction +=== + +The Power Supply charging driver connects multiple subsystems +to do charging in a generic way. The subsystems involves power_supply, +thermal and battery communication subsystems (e.g. 1wire). With this the +charging is handled in a generic way by plugging the driver to power supply +subsystem. + +The driver introduces different new features - Battery Identification +interfaces, pluggable charging algorithms, charger cable arbitrations etc. + +In existing driver implementations the charging is done based on the static +battery characteristics. This is done at the boot time by passing the battery +properties (max_voltage, capacity) etc. as a platform data to the +charger/battery driver. But new generation high volt batteries needs to be +identified dynamically to do charging in a safe manner. The batteries are +coming with different communication protocols. It becomes necessary to +communicate with battery and identify it's charging profiles before setup +charging. + +Also the charging algorithms can vary based on the battery characteristics +and the platform characteristics. To handle charging in a generic way it's +necessary to support pluggable charging algorithms. Power Supply Charging +driver selects algorithms based on the type of battery charging profile. +This is a simple binding and can be improved later. This may be improved to +select the algorithms based on the platform requirements. Also we can extend +this driver to plug algorithms from the user space. + +The driver also introduces the charger cable arbitration. A charger may +supports multiple cables, but it may not be able to charge with multiple +cables at a time (USB/AC/Wireless etc.). The arbitration logic inside the +driver selects the cable based on it's capabilities and the maximum +charge current the platform can support. + +Also the driver exposes features to control charging on different platform +states. One such feature is thermal. The driver handles the thermal +throttling requests for charging and control charging based on the thermal +subsystem requirements. + +Overall this driver removes the charging logic out of the charger chip driver +and the charger chip driver just listen to the request from the power +supply charging driver to set the charger properties. This is accomplished +by exposing get_property and set_property callbacks. + +2. Reading Battery charging profile +=== + +Power Supply charging driver expose APIs to retrieve battery profile of a +battery. The battery profile can be read by battery identification driver which +may be 1wire/I2C/SFI driver. Battery identification driver can register the +battery profile with the power supply charging driver using the API +psy_battery_profile_changed(). The driver also exposes API +psy_get_battery_profile() to retrieve the battery profile which can be +used by power supply drivers to setup the charging. Also drivers +can register for battery removal/insertion notifications using +power_supply_reg_notifier() + +3. Use Charging Driver to setup charging
[PATCH 1/3] power_supply: Introduce generic psy charging driver
The Power Supply charging driver connects multiple subsystems to do charging in a generic way. The subsystems involves power_supply, thermal and battery communication subsystems (1wire). With this the charging is handled in a generic way. The driver makes use of different new features - Battery Identification interfaces, pluggable charging algorithms, charger cable arbitrations etc. The patch also introduces generic interface for charger cable notifications. Charger cable events and capabilities can be notified using the generic power_supply_notifier chain. Overall this driver removes the charging logic out of the charger chip driver and the charger chip driver can just listen to the request from the power supply charging driver to set the charger properties. This can be implemented by exposing get_property and set_property callbacks. Signed-off-by: Jenny TC jenny...@intel.com --- Documentation/power/power_supply_charger.txt | 349 drivers/power/Kconfig|8 + drivers/power/Makefile |1 + drivers/power/power_supply_charger.c | 1206 ++ drivers/power/power_supply_charger.h | 224 + drivers/power/power_supply_core.c|3 + include/linux/power/power_supply_charger.h | 308 +++ include/linux/power_supply.h | 161 8 files changed, 2260 insertions(+) create mode 100644 Documentation/power/power_supply_charger.txt create mode 100644 drivers/power/power_supply_charger.c create mode 100644 drivers/power/power_supply_charger.h create mode 100644 include/linux/power/power_supply_charger.h diff --git a/Documentation/power/power_supply_charger.txt b/Documentation/power/power_supply_charger.txt new file mode 100644 index 000..6ae59ea --- /dev/null +++ b/Documentation/power/power_supply_charger.txt @@ -0,0 +1,349 @@ +1. Introduction +=== + +The Power Supply charging driver connects multiple subsystems +to do charging in a generic way. The subsystems involves power_supply, +thermal and battery communication subsystems (e.g. 1wire). With this the +charging is handled in a generic way by plugging the driver to power supply +subsystem. + +The driver introduces different new features - Battery Identification +interfaces, pluggable charging algorithms, charger cable arbitrations etc. + +In existing driver implementations the charging is done based on the static +battery characteristics. This is done at the boot time by passing the battery +properties (max_voltage, capacity) etc. as a platform data to the +charger/battery driver. But new generation high volt batteries needs to be +identified dynamically to do charging in a safe manner. The batteries are +coming with different communication protocols. It becomes necessary to +communicate with battery and identify it's charging profiles before setup +charging. + +Also the charging algorithms can vary based on the battery characteristics +and the platform characteristics. To handle charging in a generic way it's +necessary to support pluggable charging algorithms. Power Supply Charging +driver selects algorithms based on the type of battery charging profile. +This is a simple binding and can be improved later. This may be improved to +select the algorithms based on the platform requirements. Also we can extend +this driver to plug algorithms from the user space. + +The driver also introduces the charger cable arbitration. A charger may +supports multiple cables, but it may not be able to charge with multiple +cables at a time (USB/AC/Wireless etc.). The arbitration logic inside the +driver selects the cable based on it's capabilities and the maximum +charge current the platform can support. + +Also the driver exposes features to control charging on different platform +states. One such feature is thermal. The driver handles the thermal +throttling requests for charging and control charging based on the thermal +subsystem requirements. + +Overall this driver removes the charging logic out of the charger chip driver +and the charger chip driver just listen to the request from the power +supply charging driver to set the charger properties. This is accomplished +by exposing get_property and set_property callbacks. + +2. Reading Battery charging profile +=== + +Power Supply charging driver expose APIs to retrieve battery profile of a +battery. The battery profile can be read by battery identification driver which +may be 1wire/I2C/SFI driver. Battery identification driver can register the +battery profile with the power supply charging driver using the API +psy_battery_profile_changed(). The driver also exposes API +psy_get_battery_profile() to retrieve the battery profile which can be +used by power supply drivers to setup the charging. Also drivers +can register for battery removal/insertion notifications using +power_supply_reg_notifier() + +3. Use Charging Driver to setup
