Re: [PATCH v3 10/24] drm/sun4i: tcon: Generalize engine search algorithm

From: Jernej Åkrabec
Date: Fri Jun 29 2018 - 15:07:47 EST


Dne Äetrtek, 28. junij 2018 ob 20:25:43 CEST je Maxime Ripard napisal(a):
> On Thu, Jun 28, 2018 at 06:48:50AM +0200, Jernej Åkrabec wrote:
> > Dne Äetrtek, 28. junij 2018 ob 04:06:52 CEST je Chen-Yu Tsai napisal(a):
> > > On Mon, Jun 25, 2018 at 8:02 PM, Jernej Skrabec
> > > <jernej.skrabec@xxxxxxxx>
> >
> > wrote:
> > > > Current "old" method to find engine worked pretty well for DE2.
> > > > However,
> > > > it doesn't work when TCON TOP is between mixer (engine) and TCON.
> > > > TCON
> > > > TOP has multiple input ports, but current engine search algorithm
> > > > expects only one.
> > > >
> > > > This can be fixed by first looking for output port id and selecting
> > > > matching input by subtracting 1 for the next round. This work even if
> > > > there is only one input and output.
> > > >
> > > > Signed-off-by: Jernej Skrabec <jernej.skrabec@xxxxxxxx>
> > > > ---
> > > >
> > > > drivers/gpu/drm/sun4i/sun4i_tcon.c | 22 ++++++++++++++++++----
> > > > 1 file changed, 18 insertions(+), 4 deletions(-)
> > > >
> > > > diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> > > > b/drivers/gpu/drm/sun4i/sun4i_tcon.c index 08747fc3ee71..264bcc43da11
> > > > 100644
> > > > --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> > > > +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> > > > @@ -791,12 +791,14 @@ static int sun4i_tcon_init_regmap(struct device
> > > > *dev,
> > > >
> > > > */
> > > >
> > > > static struct sunxi_engine *
> > > > sun4i_tcon_find_engine_traverse(struct sun4i_drv *drv,
> > > >
> > > > - struct device_node *node)
> > > > + struct device_node *node,
> > > > + u32 port_id)
> > > >
> > > > {
> > > >
> > > > struct device_node *port, *ep, *remote;
> > > > struct sunxi_engine *engine = ERR_PTR(-EINVAL);
> > > >
> > > > + u32 reg = 0;
> > > >
> > > > - port = of_graph_get_port_by_id(node, 0);
> > > > + port = of_graph_get_port_by_id(node, port_id);
> > > >
> > > > if (!port)
> > > >
> > > > return ERR_PTR(-EINVAL);
> > > >
> > > > @@ -826,8 +828,20 @@ sun4i_tcon_find_engine_traverse(struct sun4i_drv
> > > > *drv,
> > > >
> > > > if (remote == engine->node)
> > > >
> > > > goto out_put_remote;
> > > >
> > > > + /*
> > > > + * According to device tree binding input ports have even id
> > > > + * number and output ports have odd id. Since component with
> > > > + * more than one input and one output (TCON TOP) exits,
> > > > correct
> > > > + * remote input id has to be calculated by subtracting 1 from
> > > > + * remote output id. If this for some reason can't be done, 0
> > > > + * is used as input port id.
> > > > + */
> > >
> > > You need to call
> > >
> > > of_node_put(port);
> > >
> > > to drop the reference to the original port.
> >
> > Thanks for noticing it. I guess I should send fix patch, since patches
> > from
> > drm-misc-next can't be dropped.
>
> Yeah, please send additional patches for all the issues pointed out by
> Chen-Yu.

Of course. I hope this can be resolved till the end of the next week. After
that, I will be away from PC for 2 weeks. Feel free to drop DT patches if you
think that it will come too close to merge window.

Best regards,
Jernej