diff options
| author | Jisheng Zhang <jszhang@kernel.org> | 2026-01-29 10:15:34 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-02-05 17:16:24 +0100 |
| commit | a52e4f2dff413b58c7200e89bb6540bd995e1269 (patch) | |
| tree | e64904e350bd10f72dc6530ca7f2fb61b9564446 | |
| parent | 87e4b043b98a1d269be0b812f383881abee0ca45 (diff) | |
usb: dwc2: fix resume failure if dr_mode is host
commit 13b1f8e25bfd1 ("usb: dwc2: Force mode optimizations") removed the
dwc2_force_mode(hsotg, true) in dwc2_force_dr_mode() if dr_mode is host.
But this brings a bug: the controller fails to resume back as host,
further debugging shows that the controller is resumed as peripheral.
The reason is dwc2_force_dr_mode() missed the host mode forcing, and
when resuming from s2ram, GINTSTS is 0 by default, dwc2_is_device_mode
in dwc2_resume() misreads this as the controller is in peripheral mode.
Fix the resume failure by adding back the dwc2_force_mode(hsotg, true).
Then an obvious question is: why this bug hasn't been observed and fixed
for about six years? There are two resons: most dwc2 platforms set the
dr_mode as otg; Some platforms don't have suspend & resume support yet.
Fixes: 13b1f8e25bfd1 ("usb: dwc2: Force mode optimizations")
Cc: stable <stable@kernel.org>
Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
Link: https://patch.msgid.link/20260129021534.10411-1-jszhang@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/dwc2/core.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/usb/dwc2/core.c b/drivers/usb/dwc2/core.c index c3d24312db0f..f375c5185bfe 100644 --- a/drivers/usb/dwc2/core.c +++ b/drivers/usb/dwc2/core.c @@ -578,6 +578,7 @@ void dwc2_force_dr_mode(struct dwc2_hsotg *hsotg) { switch (hsotg->dr_mode) { case USB_DR_MODE_HOST: + dwc2_force_mode(hsotg, true); /* * NOTE: This is required for some rockchip soc based * platforms on their host-only dwc2. |