Hi Sebastian, On 2024-05-31 17:08, Sebastian Reichel wrote: > Hi, > > On ROCK 5B power is usually supplied via it's USB-C port. This port has the > data lines connected to RK3588, VBUS connected to the input regulator and > CC pins connected to FUSB302. FUSB302 is a USB-C controller, which can be > accessed via I2C from RK3588. The USB-C controller is needed to figure out > the USB-C cable orientation, but also to do USB PD communication. Thus it > would be great to enable support for it in the operating system. > > But the USB-PD specification requires, that a device reacts to USB-PD messages > send by the power-supply within around 5 seconds. If that does not happen the > power-supply assumes, that the device does not support USB-PD. If a device > later starts sending USB-PD messages it is considered an error, which is > solved > by doing a hard reset. A USB-PD hard reset means, that all supply voltages are > removed for a short period of time. For boards, which are solely powered > through their USB-C port, like the Radxa Rock 5B, this results in an machine > reset. This is currently worked around by not describing the FUSB302 in the > kernel DT, so nothing will ever speak USB-PD on the Rock 5B. This means > > 1. the USB-C port cannot be used at all > 2. the board will be running via fallback supply, which provides limited > power capabilities > > In order to avoid the hard reset, this adds FUSB302 support to U-Boot, so > that we react to the power-supply's queries in time. The code, which is > originally from the Linux kernel, consists of two parts: > > 1. the tcpm state machine, which implements the Type C port manager state > machine as described in the USB PD specification > 2. the fusb302 driver, which knows about specific registers > > Especially the first part has been heavily modified compared to the > kernel, which makes use of multiple delayed works and threads. For this > I used a priorly ported version from Rockchip, removed their hacks and > any states not necessary in U-Boot (e.g. audio accessory support).
Thanks for working on this! Some initial quick feedback is that the tcpm uclass and driver should probably take more advantage of the u-boot driver model. Few quick thoughts: - Split out uclass/driver api parts into tcpm-uclass.c - Take advantage of uclass_driver ops such as post_probe and per_device_auto/per_device_plat_auto to e.g. handle tcpm_port_init and tcpm_port/tcpm_dev - udevice should probably be passed to tcpm_ functions instead of a tcpm_port, dev_get_uclass_plat/priv could possible be used to get the tcpm_port data for the udevice I have not yet had time to runtime test this but will do and get back with a more in depth review later this week. Regards, Jonas > > Greetings, > > -- Sebastian > > Sebastian Reichel (5): > usb: tcpm: add core framework > usb: tcpm: fusb302: add driver > board: rock5b-rk3588: add USB-C controller support > board: rock5b-rk3588: enable USB-C in operating system > MAINTAINERS: add TCPM section > > MAINTAINERS | 8 + > Makefile | 1 + > arch/arm/dts/rk3588-rock-5b-u-boot.dtsi | 28 + > board/radxa/rock5b-rk3588/Makefile | 6 + > board/radxa/rock5b-rk3588/rock5b-rk3588.c | 33 + > cmd/Kconfig | 7 + > cmd/Makefile | 1 + > cmd/tcpm.c | 117 + > configs/rock5b-rk3588_defconfig | 5 + > drivers/usb/Kconfig | 2 + > drivers/usb/tcpm/Kconfig | 16 + > drivers/usb/tcpm/Makefile | 4 + > drivers/usb/tcpm/fusb302.c | 1427 ++++++++++++ > drivers/usb/tcpm/fusb302_reg.h | 177 ++ > drivers/usb/tcpm/tcpm.c | 2406 +++++++++++++++++++++ > include/dm/uclass-id.h | 1 + > include/usb/pd.h | 516 +++++ > include/usb/tcpm.h | 116 + > 18 files changed, 4871 insertions(+) > create mode 100644 board/radxa/rock5b-rk3588/Makefile > create mode 100644 board/radxa/rock5b-rk3588/rock5b-rk3588.c > create mode 100644 cmd/tcpm.c > create mode 100644 drivers/usb/tcpm/Kconfig > create mode 100644 drivers/usb/tcpm/Makefile > create mode 100644 drivers/usb/tcpm/fusb302.c > create mode 100644 drivers/usb/tcpm/fusb302_reg.h > create mode 100644 drivers/usb/tcpm/tcpm.c > create mode 100644 include/usb/pd.h > create mode 100644 include/usb/tcpm.h >
