[PATCH] drm: bridge: dw-hdmi: Avoid resetting force in the detect function

[Jonathan Liu]

Hi Sam,

On Sun, 8 Nov 2020 at 21:47, Sam Ravnborg <sam at ravnborg.org> wrote:
>
> Hi Russell,
>
> On Sun, Nov 08, 2020 at 09:57:25AM +0000, Russell King - ARM Linux admin wrote:
> > On Sun, Nov 08, 2020 at 10:53:22AM +0100, Sam Ravnborg wrote:
> > > Russell,
> > >
> > > On Sat, Oct 31, 2020 at 07:17:47PM +1100, Jonathan Liu wrote:
> > > > It has been observed that resetting force in the detect function can
> > > > result in the PHY being powered down in response to hot-plug detect
> > > > being asserted, even when the HDMI connector is forced on.
> > > >
> > > > Enabling debug messages and adding a call to dump_stack() in
> > > > dw_hdmi_phy_power_off() shows the following in dmesg:
> > > > [  160.637413] dwhdmi-rockchip ff940000.hdmi: EVENT=plugin
> > > > [  160.637433] dwhdmi-rockchip ff940000.hdmi: PHY powered down in 0 iterations
> > > >
> > > > Call trace:
> > > > dw_hdmi_phy_power_off
> > > > dw_hdmi_phy_disable
> > > > dw_hdmi_update_power
> > > > dw_hdmi_detect
> > > > dw_hdmi_connector_detect
> > > > drm_helper_probe_detect_ctx
> > > > drm_helper_hpd_irq_event
> > > > dw_hdmi_irq
> > > > irq_thread_fn
> > > > irq_thread
> > > > kthread
> > > > ret_from_fork
> > > >
> > > > Fixes: 381f05a7a842 ("drm: bridge/dw_hdmi: add connector mode forcing")
> > > > Signed-off-by: Jonathan Liu <net147 at gmail.com>
> > >
> > > you are the original author of this code - any comments on this patch?
> >
> > No further comments beyond what has already been discussed, and the
> > long and short of it is it's been so long that I don't remember why
> > that code was there. Given that, I'm not even in a position to ack
> > the change. Sorry.
> Thanks for the quick reply.
>
> Given that this fixes a problem for Jonathan I will apply this to -fixes
> if there is no other feedback the next couple of days.
> If it introduces regression we can take it from there.
>
> Jonathan - please ping me if I forget.
>
>         Sam

Ping.

Regards,
Jonathan