Hi Udipto,
On Wed, Mar 15, 2023 at 06:17:05PM +0530, Udipto Goswami wrote:
> When the dwc3 device is runtime suspended, various required clocks would
> get disabled 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, bail out of debugfs
> function is dwc3 is suspended.
>
> Signed-off-by: Udipto Goswami <quic_ugoswami@xxxxxxxxxxx>
> ---
> v2: Replaced return 0 with -EINVAL & seq_puts with pr_err.
>
> drivers/usb/dwc3/debugfs.c | 50 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 50 insertions(+)
>
> diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c
> index 850df0e6bcab..0e6cf7b89f8b 100644
> --- a/drivers/usb/dwc3/debugfs.c
> +++ b/drivers/usb/dwc3/debugfs.c
> @@ -544,6 +544,11 @@ static int dwc3_link_state_show(struct seq_file *s, void *unused)
> u32 reg;
> u8 speed;
>
> + if (pm_runtime_suspended(dwc->dev)) {
> + pr_err("Invalid operation, DWC3 suspended!");
Use dev_err() please.
Thanks,
Jack
