]> 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>
Wed, 24 May 2023 16:36:52 +0000 (17:36 +0100)
commitc51a131cacf41793c661e3c32f6fe3bd3dc0f67d
treea5a44e065861b07e45ad0e72b93abe5f950ad0dd
parent720be29c7d1c248ec9d7886d5a1ecc375996ccc0
usb: dwc3: debugfs: Resume dwc3 before accessing registers

commit 614ce6a2ea50068b45339257891e51e639ac9001 upstream.

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