diff options
author | Wesley Cheng <quic_wcheng@quicinc.com> | 2022-03-16 02:13:58 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-03-18 12:58:46 +0100 |
commit | 0066472de157439d58454f4a55786f1045ea5681 (patch) | |
tree | e5adba36d25b6f4c7726a1a3a65422aa97a15381 /drivers/usb | |
parent | usb: gadget: Makefile: remove ccflags-y (diff) | |
download | linux-0066472de157439d58454f4a55786f1045ea5681.tar.xz linux-0066472de157439d58454f4a55786f1045ea5681.zip |
usb: dwc3: Issue core soft reset before enabling run/stop
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.
Reviewed-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Link: https://lore.kernel.org/r/20220316011358.3057-1-quic_wcheng@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r-- | drivers/usb/dwc3/core.c | 4 | ||||
-rw-r--r-- | drivers/usb/dwc3/core.h | 2 | ||||
-rw-r--r-- | 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 416d83a055fe..1170b800acdc 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 e9b1e9b8f1f3..5c9d467195a6 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 2a96826b7efd..ab725d2262d6 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2578,6 +2578,17 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on) dwc->ev_buf->length; } } else { + /* + * In the Synopsys DWC_usb31 1.90a programming guide 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); __dwc3_gadget_start(dwc); } |