Re: [PATCH 05/10] drm/tidss: Return error value from from softreset

[Tomi Valkeinen]

On 01/11/2023 15:59, Laurent Pinchart wrote:
> Hi Tomi,
>
> Thank you for the patch.
>
> On Wed, Nov 01, 2023 at 11:17:42AM +0200, Tomi Valkeinen wrote:
> > Return an error value from dispc_softreset() so that the caller can
> > handle the errors.
> >
> > Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
> > ---
> >   drivers/gpu/drm/tidss/tidss_dispc.c | 17 ++++++++++++-----
> >   1 file changed, 12 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c
> > index 9430625e2d62..cdbb88289082 100644
> > --- a/drivers/gpu/drm/tidss/tidss_dispc.c
> > +++ b/drivers/gpu/drm/tidss/tidss_dispc.c
> > @@ -2702,7 +2702,7 @@ static void dispc_init_errata(struct dispc_device *dispc)
> >   	}
> >   }
> >   
> > -static void dispc_softreset(struct dispc_device *dispc)
> > +static int dispc_softreset(struct dispc_device *dispc)
> >   {
> >   	u32 val;
> >   	int ret;
> > @@ -2712,8 +2712,12 @@ static void dispc_softreset(struct dispc_device *dispc)
> >   	/* Wait for reset to complete */
> >   	ret = readl_poll_timeout(dispc->base_common + DSS_SYSSTATUS,
> >   				 val, val & 1, 100, 5000);
> > -	if (ret)
> > -		dev_warn(dispc->dev, "failed to reset dispc\n");
> > +	if (ret) {
> > +		dev_err(dispc->dev, "failed to reset dispc\n");
> > +		return ret;
> > +	}
> > +
> > +	return 0;
> >   }
> >   
> >   int dispc_init(struct tidss_device *tidss)
> > @@ -2828,8 +2832,11 @@ int dispc_init(struct tidss_device *tidss)
> >   	tidss->dispc = dispc;
> >   
> >   	/* K2G display controller does not support soft reset */
> > -	if (feat->subrev != DISPC_K2G)
> > -		dispc_softreset(dispc);
> > +	if (feat->subrev != DISPC_K2G) {
> > +		r = dispc_softreset(dispc);
> > +		if (r)
> > +			return r;
>
> tidss->dispc will be set in this case. Could that cause problems ?

Not at the moment, but better be safe. I'll move the reset a few lines 
higher.

 Tomi