[PATCH] drm/gma500: Check power status before accessing lid data in opregion

[Patrik Jakobsson]

On Fri, Apr 12, 2024 at 10:02 AM Thomas Zimmermann <tzimmermann at suse.de> wrote:
>
> Hi,
>
> the issue of hanging during boot is still resent.

Thanks for testing. Then it cannot be that psb_lid_timer_func runs
before initialization. The BUG from Enrico hints that the
set_brightness function is called before initialization. That might be
another place to look.

I'll see if I can do some testing on my own.

>
> Best regards
> Thomas
>
> Am 12.04.24 um 09:24 schrieb Patrik Jakobsson:
> > Due to changes in the order of initialization the psb_lid_timer_func
> > could get called without the device being powered. Fix this by checking
> > the power status before accessing the opregion.
> >
> > Cc: Enrico Bartky <enrico.bartky at gmail.com>
> > Cc: Thomas Zimmermann <tzimmermann at suse.de>
> > Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson at gmail.com>
> > ---
> >   drivers/gpu/drm/gma500/psb_lid.c | 10 +++++++++-
> >   1 file changed, 9 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/gma500/psb_lid.c b/drivers/gpu/drm/gma500/psb_lid.c
> > index 58a7fe392636..eeb91d11336e 100644
> > --- a/drivers/gpu/drm/gma500/psb_lid.c
> > +++ b/drivers/gpu/drm/gma500/psb_lid.c
> > @@ -10,6 +10,7 @@
> >   #include "psb_drv.h"
> >   #include "psb_intel_reg.h"
> >   #include "psb_reg.h"
> > +#include "power.h"
> >
> >   static void psb_lid_timer_func(struct timer_list *t)
> >   {
> > @@ -20,9 +21,12 @@ static void psb_lid_timer_func(struct timer_list *t)
> >       u32 __iomem *lid_state = dev_priv->opregion.lid_state;
> >       u32 pp_status;
> >
> > -     if (readl(lid_state) == dev_priv->lid_last_state)
> > +     if (!gma_power_begin(dev, false))
> >               goto lid_timer_schedule;
> >
> > +     if (readl(lid_state) == dev_priv->lid_last_state)
> > +             goto power_end;
> > +
> >       if ((readl(lid_state)) & 0x01) {
> >               /*lid state is open*/
> >               REG_WRITE(PP_CONTROL, REG_READ(PP_CONTROL) | POWER_TARGET_ON);
> > @@ -36,6 +40,7 @@ static void psb_lid_timer_func(struct timer_list *t)
> >                       psb_intel_lvds_set_brightness(dev, 100);
> >               } else {
> >                       DRM_DEBUG("LVDS panel never powered up");
> > +                     gma_power_end(dev);
> >                       return;
> >               }
> >       } else {
> > @@ -48,6 +53,9 @@ static void psb_lid_timer_func(struct timer_list *t)
> >       }
> >       dev_priv->lid_last_state =  readl(lid_state);
> >
> > +power_end:
> > +     gma_power_end(dev);
> > +
> >   lid_timer_schedule:
> >       spin_lock_irqsave(&dev_priv->lid_lock, irq_flags);
> >       if (!timer_pending(lid_timer)) {
>
> --
> --
> Thomas Zimmermann
> Graphics Driver Developer
> SUSE Software Solutions Germany GmbH
> Frankenstrasse 146, 90461 Nuernberg, Germany
> GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman
> HRB 36809 (AG Nuernberg)
>