Hi wesley,
On Tue, Feb 15, 2022 at 04:08:35PM -0800, Wesley Cheng wrote:
> It is recommended by the Synopsis databook to issue a DCTL.CSftReset
> when reconnecting from a device-initiated disconnect routine. This
> resolves issues with enumeration during fast composition switching
> cases, which result in an unknown device on the host.
>
> Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
> ---
> drivers/usb/dwc3/core.c | 4 +---
> drivers/usb/dwc3/core.h | 2 ++
> drivers/usb/dwc3/gadget.c | 11 +++++++++++
> 3 files changed, 14 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 18adddfba3da..02d10e1cb774 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -115,8 +115,6 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode)
> dwc->current_dr_role = mode;
> }
>
> -static int dwc3_core_soft_reset(struct dwc3 *dwc);
> -
> static void __dwc3_set_mode(struct work_struct *work)
> {
> struct dwc3 *dwc = work_to_dwc(work);
> @@ -261,7 +259,7 @@ u32 dwc3_core_fifo_space(struct dwc3_ep *dep, u8 type)
> * dwc3_core_soft_reset - Issues core soft reset and PHY reset
> * @dwc: pointer to our context structure
> */
> -static int dwc3_core_soft_reset(struct dwc3 *dwc)
> +int dwc3_core_soft_reset(struct dwc3 *dwc)
> {
> u32 reg;
> int retries = 1000;
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 00348d6d479b..b27ad8dad317 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1532,6 +1532,8 @@ bool dwc3_has_imod(struct dwc3 *dwc);
> int dwc3_event_buffers_setup(struct dwc3 *dwc);
> void dwc3_event_buffers_cleanup(struct dwc3 *dwc);
>
> +int dwc3_core_soft_reset(struct dwc3 *dwc);
> +
> #if IS_ENABLED(CONFIG_USB_DWC3_HOST) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
> int dwc3_host_init(struct dwc3 *dwc);
> void dwc3_host_exit(struct dwc3 *dwc);
> diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
> index 0c89baedf220..788889f924f9 100644
> --- a/drivers/usb/dwc3/gadget.c
> +++ b/drivers/usb/dwc3/gadget.c
> @@ -2585,6 +2585,17 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
> dwc->ev_buf->length;
> }
> } else {
> + /*
> + * In the Synopsis DesignWare Cores USB3 Databook Rev. 1.90a
> + * Section 4.1.9, it specifies that for a reconnect after a
> + * device-initiated disconnect requires a core soft reset
> + * (DCTL.CSftRst) before enabling the run/stop bit.
> + */
> + spin_unlock_irqrestore(&dwc->lock, flags);
> + dwc3_core_soft_reset(dwc);
> + spin_lock_irqsave(&dwc->lock, flags);
> +
> + dwc3_event_buffers_setup(dwc);
Could you tell me why you add dwc3_event_buffer_setup?
Best Regards,
Jung Daehwan
> __dwc3_gadget_start(dwc);
> }
>
>
