On 17-01-19, 17:44, Yoshihiro Shimoda wrote:
> From: Phuong Nguyen <phuong.nguyen.xw@xxxxxxxxxxx>
>
> This commit fixes the issue that USB-DMAC hangs silently after system
> resumes on R-Car Gen3 hence renesas_usbhs will not work correctly
> when using USB-DMAC for bulk transfer e.g. ethernet or serial
> gadgets.
>
> The issue can be reproduced by these steps:
> 1. modprobe g_serial
> 2. Suspend and resume system.
> 3. connect a usb cable to host side
> 4. Transfer data from Host to Target
> 5. cat /dev/ttyGS0 (Target side)
> 6. echo "test" > /dev/ttyACM0 (Host side)
>
> The 'cat' will not result anything. However, system still can work
> normally.
>
> Currently, USB-DMAC driver does not have system sleep callbacks hence
> this driver relies on the PM core to force runtime suspend/resume to
> suspend and reinitialize USB-DMAC during system resume. After
> the commit 17218e0092f8 ("PM / genpd: Stop/start devices without
> pm_runtime_force_suspend/resume()"), PM core will not force
> runtime suspend/resume anymore so this issue happens.
>
> To solve this, make system suspend resume explicit by using
> pm_runtime_force_{suspend,resume}() as the system sleep callbacks.
> SET_NOIRQ_SYSTEM_SLEEP_PM_OPS() is used to make sure USB-DMAC
> suspended after and initialized before renesas_usbhs."
Applied, thanks
--
~Vinod
