]> git.itanic.dy.fi Git - linux-stable/commit
usb: dwc3: debugfs: Resume dwc3 before accessing registers
authorUdipto Goswami <quic_ugoswami@quicinc.com>
Tue, 9 May 2023 14:48:36 +0000 (20:18 +0530)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 13 May 2023 08:56:22 +0000 (17:56 +0900)
commit614ce6a2ea50068b45339257891e51e639ac9001
treea619112241a554311ed217e1c89a5b04c4df72c0
parentdddb342b5b9e482bb213aecc08cbdb201ea4f8da
usb: dwc3: debugfs: Resume dwc3 before accessing registers

When the dwc3 device is runtime suspended, various required clocks are in
disabled state and it is not guaranteed that access to any registers would
work. Depending on the SoC glue, a register read could be as benign as
returning 0 or be fatal enough to hang the system.

In order to prevent such scenarios of fatal errors, make sure to resume
dwc3 then allow the function to proceed.

Fixes: 72246da40f37 ("usb: Introduce DesignWare USB3 DRD Driver")
Cc: stable@vger.kernel.org #3.2: 30332eeefec8: debugfs: regset32: Add Runtime PM support
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20230509144836.6803-1-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/dwc3/debugfs.c