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authorWesley Cheng <wcheng@codeaurora.org>2021-08-03 23:24:05 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-08-05 11:02:00 +0200
commitcb10f68ad8150f243964b19391711aaac5e8ff42 (patch)
tree6d1d4333f711163d50c7ae1a0b4bebad56f69da1 /drivers/usb
parentd25d85061bd856d6be221626605319154f9b5043 (diff)
usb: dwc3: gadget: Avoid runtime resume if disabling pullup
If the device is already in the runtime suspended state, any call to the pullup routine will issue a runtime resume on the DWC3 core device. If the USB gadget is disabling the pullup, then avoid having to issue a runtime resume, as DWC3 gadget has already been halted/stopped. This fixes an issue where the following condition occurs: usb_gadget_remove_driver() -->usb_gadget_disconnect() -->dwc3_gadget_pullup(0) -->pm_runtime_get_sync() -> ret = 0 -->pm_runtime_put() [async] -->usb_gadget_udc_stop() -->dwc3_gadget_stop() -->dwc->gadget_driver = NULL ... dwc3_suspend_common() -->dwc3_gadget_suspend() -->DWC3 halt/stop routine skipped, driver_data == NULL This leads to a situation where the DWC3 gadget is not properly stopped, as the runtime resume would have re-enabled EP0 and event interrupts, and since we avoided the DWC3 gadget suspend, these resources were never disabled. Fixes: 77adb8bdf422 ("usb: dwc3: gadget: Allow runtime suspend if UDC unbinded") Cc: stable <stable@vger.kernel.org> Acked-by: Felipe Balbi <balbi@kernel.org> Signed-off-by: Wesley Cheng <wcheng@codeaurora.org> Link: https://lore.kernel.org/r/1628058245-30692-1-git-send-email-wcheng@codeaurora.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb')
-rw-r--r--drivers/usb/dwc3/gadget.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index a1b262669574..b8d4b2d327b2 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2257,6 +2257,17 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on)
}
/*
+ * Avoid issuing a runtime resume if the device is already in the
+ * suspended state during gadget disconnect. DWC3 gadget was already
+ * halted/stopped during runtime suspend.
+ */
+ if (!is_on) {
+ pm_runtime_barrier(dwc->dev);
+ if (pm_runtime_suspended(dwc->dev))
+ return 0;
+ }
+
+ /*
* 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.