Hi,
On 04.06.24 18:33, 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
- the USB-C port cannot be used at all
- 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:
- the tcpm state machine, which implements the Type C port manager state machine as described in the USB PD specification
- 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).
Changes since PATCHv1:
- tcpm: split uclass specific code to tcpm-uclass
- tcpm_print_info: move printing part to cmd/tcpm.c
- tcpm_print_info: report more information
- PD revision
- Cable orientation
- Power role
- Data role
- Print TCPM state based on connection status
- tcpm: use "struct udevice *dev" instead of "struct tcpm_port *port" as function argument in most places and drop dev from the tcpm_port struct
- tcpm: avoid useless kzalloc + copy + free for incoming events
- tcpm: use dev_get_uclass_plat() for tcpm_port
- tcpm: run tcpm_port_init() and tcpm_poll_event() from UCLASS post_probe()
- tcpm/fusb302: get rid of tcpc_dev by using dm_tcpm_ops() for the function pointers and introducing get_connector_node() for the ofnode
- fusb302: use "struct udevice *dev" instead of "struct fusb302_chip *chip" as function argument and drop dev from the fusb302_chip struct
- fusb302: drop multiple unused members from fusb302_chip
- fusb302: directly use udelay instead of usleep_range define
- fusb302: use fusb302_ prefix for all functions. Afterwards tcpm_ prefix is only used for the tcpm code itself
- fusb302: move fusb302_poll_event() to avoid forward defintion
- fusb302: drop probe function
- fusb302: drop unused LOG_BUFFER defines
- roughly 20% of all lines of the series changed between v1 and v2, so I did not collect the Tested-by from Soeren Moch
Makes sense, of course.
I retested this v2 series on top of 2024.07-rc4, everything still works perfectly fine for me.
Tested-by: Soeren Moch smoch@web.de
U-Boot 2024.07-rc4-00005-gc9c6c70498 (Jun 04 2024 - 19:18:57 +0200)
Model: Radxa ROCK 5 Model B DRAM: 8 GiB Core: 355 devices, 33 uclasses, devicetree: separate MMC: mmc@fe2c0000: 1, mmc@fe2d0000: 2, mmc@fe2e0000: 0 Loading Environment from nowhere... OK In: serial@feb50000 Out: serial@feb50000 Err: serial@feb50000 Model: Radxa ROCK 5 Model B Net: No ethernet found. Hit any key to stop autoboot: 0 => tcpm list | Name | Parent name | Parent uclass @ seq | usb-typec@22 | i2c@feac0000 | i2c @ 4 | status: 0 => tcpm dev usb-typec@22 dev: 0 @ usb-typec@22 => tcpm info Orientation: normal PD Revision: rev3 Power Role: sink Data Role: device Voltage: 12.000 V Current: 2.500 A =>
Thanks again, Soeren