On Theobroma Ringneck SoM, USB peripheral role when in dual-role mode does not work and displays the following error message: dwc2 ff300000.usb: dwc2_core_reset: HANG! Soft Reset timeout GRSTCTL_CSFTRST The USB sniffer shows nothing and dumping the host registers is stuck on HCDMA(0) register. Note that for some reason it works "fine" on PX30-EVB (there's another issue but not related to/fixed in this patch series). Since there's no documentation available for this IP, this patch series is basically just slightly adapted downstream BSP vendor kernel patches and I cannot unfortunately give more information than what I have. This patch series was tested on Theobroma Ringneck SoM on Haikou devkit and PX30 EVB. It fixes Ringneck support and does not break PX30-EVB's. For reference, the content of those commits can be found in tag linux-5.10-gen-rkr1, and the following commits have been used: 964d50060bf53a8defd1fc561b9261424f25ddad ad81c375602819a538ad68d979906c05663046e2 6e6adab8f735bc4fe27a67bdc3144d8fa89250d4 7c3a4e60247fd7f7b04d95d15cb12c63a5c20408 Note that Rockchip kernel called a slightly different implementation of __dwc2_lowlevel_hw_enable instead of dwc2_lowlevel_hw_enable but it seemed more right to me to call dwc2_lowlevel_hw_enable as done for the forced peripheral mode. Note that it is still not flawlessly working but the support is improved (somewhat working vs not working at all). To: Minas Harutyunyan <hminas@xxxxxxxxxxxx> To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: linux-usb@xxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: Bin Yang <yangbin@xxxxxxxxxxxxxx> Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxxxxx> --- Changes in v2: - add "shadow" variable for HCD skip_phy_initialization so that it can be configured on a per-platform basis, - Patch 1 and Patch 2 of the v1 are already in linux-next next-20221216, so removed from this series, - Link to v1: https://lore.kernel.org/r/20221206-dwc2-gadget-dual-role-v1-0-36515e1092cd@xxxxxxxxxxxxxxxxxxxxx --- Quentin Schulz (2): usb: dwc2: allow platforms to prevent core phy initialisation usb: dwc2: prevent core PHY initialization on Rockchip drivers/usb/dwc2/core.h | 6 ++++++ drivers/usb/dwc2/hcd.c | 2 ++ drivers/usb/dwc2/params.c | 1 + 3 files changed, 9 insertions(+) --- base-commit: ca39c4daa6f7f770b1329ffb46f1e4a6bcc3f291 change-id: 20221206-dwc2-gadget-dual-role-aac67e6d42fd Best regards, -- Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxxxxx>
