From ec89366c1fcf73baadb7e4f969882abf39e1c716 Mon Sep 17 00:00:00 2001 From: Wesley Cheng Date: Tue, 29 Dec 2020 15:05:35 -0800 Subject: [PATCH] BACKPORT: usb: dwc3: gadget: Allow runtime suspend if UDC unbinded The DWC3 runtime suspend routine checks for the USB connected parameter to determine if the controller can enter into a low power state. The connected state is only set to false after receiving a disconnect event. However, in the case of a device initiated disconnect (i.e. UDC unbind), the controller is halted and a disconnect event is never generated. Set the connected flag to false if issuing a device initiated disconnect to allow the controller to be suspended. Signed-off-by: Wesley Cheng Link: https://lore.kernel.org/r/1609283136-22140-2-git-send-email-wcheng@codeaurora.org Signed-off-by: Greg Kroah-Hartman Bug: 177879761 (cherry picked from commit 77adb8bdf4227257e26b7ff67272678e66a0b250) Change-Id: Ida95a1274f186cf81d40489ae0bdf2c702779a7c Signed-off-by: Ray Chi --- drivers/usb/dwc3/gadget.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 4c10a58083b9..5e66518d9e7f 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2222,6 +2222,17 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on) } } + /* + * Check the return value for successful resume, or error. For a + * successful resume, the DWC3 runtime PM resume routine will handle + * the run stop sequence, so avoid duplicate operations here. + */ + ret = pm_runtime_get_sync(dwc->dev); + if (!ret || ret < 0) { + pm_runtime_put(dwc->dev); + return 0; + } + /* * Synchronize any pending event handling before executing the controller * halt routine. @@ -2260,12 +2271,14 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on) dwc->ev_buf->lpos = (dwc->ev_buf->lpos + count) % dwc->ev_buf->length; } + dwc->connected = false; } else { __dwc3_gadget_start(dwc); } ret = dwc3_gadget_run_stop(dwc, is_on, false); spin_unlock_irqrestore(&dwc->lock, flags); + pm_runtime_put(dwc->dev); return ret; }