Currently the Linux kernel does not provide any standard integration of this feature that integrates the USB subsystem with the system power regulation provided by PMICs meaning that either vendors must add this in their kernels or USB gadget devices based on Linux (such as mobile phones) may not behave as they should. Thus provide a standard framework for doing this in kernel.
Now introduce one user with wm831x_power to support and test the usb charger, which is pending testing. Moreover there may be other potential users will use it in future. Changes since v17: - Remove goto section in usb_charger_register() function. - Remove 'extern' in charger.h file. - Move the kfree() to usb_charger_exit() function. Changes since v16: - Modify the charger current range with introducing the maximum and minimum current. - Remove the getting charger type method from power supply. - Add the getting charger type method from extcon system. - Introduce new usb_charger_get_current() API for users to get the maximum and minimum current. - Rename some APIs and other optimization. Changes since v15: - Add charger state checking to avoid sending out duplicate notifies to users. - Add one work to notify power users the current has been changed. Changes since v14: - Add kernel documentation for struct usb_cahrger. - Remove some redundant WARN() functions. Changes since v13: - Remove the charger checking in usb_gadget_vbus_draw() function. - Rename some functions in charger.c file. - Rebase on git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git tags/usb-for-v4.8 Changes since v12: - Remove the class and device things. - Link usb charger to udc-core.ko. - Create one "charger" subdirectory which holds all charger-related attributes. Changes since v11: - Reviewed and tested by Li Jun. Changes since v10: - Introduce usb_charger_get_state() function to check charger state. - Remove the mutex lock in usb_charger_set_cur_limit_by_type() function in case will be issued in atomic context. Baolin Wang (4): usb: gadget: Introduce the usb charger framework usb: gadget: Support for the usb charger framework usb: gadget: Integrate with the usb gadget supporting for usb charger power: wm831x_power: Support USB charger current limit management drivers/power/wm831x_power.c | 75 ++++ drivers/usb/gadget/Kconfig | 8 + drivers/usb/gadget/udc/Makefile | 1 + drivers/usb/gadget/udc/charger.c | 877 ++++++++++++++++++++++++++++++++++++++ drivers/usb/gadget/udc/core.c | 19 +- include/linux/mfd/wm831x/pdata.h | 3 + include/linux/usb/charger.h | 185 ++++++++ include/linux/usb/gadget.h | 3 + include/uapi/linux/usb/charger.h | 31 ++ 9 files changed, 1201 insertions(+), 1 deletion(-) create mode 100644 drivers/usb/gadget/udc/charger.c create mode 100644 include/linux/usb/charger.h create mode 100644 include/uapi/linux/usb/charger.h -- 220.127.116.11