Re: [PATCH v3] media: rcar-vin: Enable YDS bit depending on bus_width and data_shift

From: Laurent Pinchart
Date: Mon Sep 14 2020 - 20:03:22 EST


Hi Niklas,

On Tue, Sep 15, 2020 at 02:01:40AM +0200, Niklas Söderlund wrote:
> On 2020-09-15 02:45:32 +0300, Laurent Pinchart wrote:
> > On Sun, Sep 13, 2020 at 07:16:08PM +0100, Lad Prabhakar wrote:
> > > Enable YDS bit if bus_width and data_shift is set to 8 in parallel mode
> > > for MEDIA_BUS_FMT_UYVY8_2X8 format.
> > >
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > > Reviewed-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > ---
> > > Changes for v3:
> > > * Dropped BIT macro
> > > * Introduced struct v4l2_fwnode_bus_parallel
> > >
> > > Changes for v2:
> > > * Dropped DT binding documentation patch
> > > * Select the data pins depending on bus-width and data-shift
> > >
> > > v1 -
> > > https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=323799
> > > ---
> > > drivers/media/platform/rcar-vin/rcar-core.c | 9 ++++-----
> > > drivers/media/platform/rcar-vin/rcar-dma.c | 17 ++++++++++++++---
> > > drivers/media/platform/rcar-vin/rcar-vin.h | 5 +++--
> > > 3 files changed, 21 insertions(+), 10 deletions(-)
> > >
> > > diff --git a/drivers/media/platform/rcar-vin/rcar-core.c b/drivers/media/platform/rcar-vin/rcar-core.c
> > > index 7440c8965d27..1149ab76cf5c 100644
> > > --- a/drivers/media/platform/rcar-vin/rcar-core.c
> > > +++ b/drivers/media/platform/rcar-vin/rcar-core.c
> > > @@ -626,12 +626,11 @@ static int rvin_parallel_parse_v4l2(struct device *dev,
> > >
> > > switch (vin->parallel->mbus_type) {
> > > case V4L2_MBUS_PARALLEL:
> > > - vin_dbg(vin, "Found PARALLEL media bus\n");
> > > - vin->parallel->mbus_flags = vep->bus.parallel.flags;
> > > - break;
> > > case V4L2_MBUS_BT656:
> > > - vin_dbg(vin, "Found BT656 media bus\n");
> > > - vin->parallel->mbus_flags = 0;
> > > + vin_dbg(vin, "Found %s media bus\n",
> > > + vin->parallel->mbus_type == V4L2_MBUS_PARALLEL ?
> > > + "PARALLEL" : "BT656");
> >
> > I'd write "parallel" and "BT.656".
>
> I agree with this change.
>
> > > + vin->parallel->bus = vep->bus.parallel;
> > > break;
> > > default:
> > > vin_err(vin, "Unknown media bus type\n");
> > > diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c b/drivers/media/platform/rcar-vin/rcar-dma.c
> > > index a5dbb90c5210..d067439b0b0d 100644
> > > --- a/drivers/media/platform/rcar-vin/rcar-dma.c
> > > +++ b/drivers/media/platform/rcar-vin/rcar-dma.c
> > > @@ -125,6 +125,7 @@
> > > #define VNDMR2_VPS (1 << 30)
> > > #define VNDMR2_HPS (1 << 29)
> > > #define VNDMR2_CES (1 << 28)
> > > +#define VNDMR2_YDS (1 << 22)
> > > #define VNDMR2_FTEV (1 << 17)
> > > #define VNDMR2_VLV(n) ((n & 0xf) << 12)
> > >
> > > @@ -698,16 +699,26 @@ static int rvin_setup(struct rvin_dev *vin)
> > >
> > > if (!vin->is_csi) {
> > > /* Hsync Signal Polarity Select */
> > > - if (!(vin->parallel->mbus_flags & V4L2_MBUS_HSYNC_ACTIVE_LOW))
> > > + if (!(vin->parallel->bus.flags & V4L2_MBUS_HSYNC_ACTIVE_LOW))
> > > dmr2 |= VNDMR2_HPS;
> > >
> > > /* Vsync Signal Polarity Select */
> > > - if (!(vin->parallel->mbus_flags & V4L2_MBUS_VSYNC_ACTIVE_LOW))
> > > + if (!(vin->parallel->bus.flags & V4L2_MBUS_VSYNC_ACTIVE_LOW))
> > > dmr2 |= VNDMR2_VPS;
> > >
> > > /* Data Enable Polarity Select */
> > > - if (vin->parallel->mbus_flags & V4L2_MBUS_DATA_ENABLE_LOW)
> > > + if (vin->parallel->bus.flags & V4L2_MBUS_DATA_ENABLE_LOW)
> > > dmr2 |= VNDMR2_CES;
> > > +
> > > + switch (vin->mbus_code) {
> > > + case MEDIA_BUS_FMT_UYVY8_2X8:
> > > + if (vin->parallel->bus.bus_width == 8 &&
> >
> > You can possibly drop this check, as UYVY8_2X8 implies a bus_width equal
> > to 8. Apart from that,
>
> I agree here as well, I think the check for UYVY8_2X8 may be dropped.
>
> > Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> >
> > > + vin->parallel->bus.data_shift == 8)
> > > + dmr2 |= VNDMR2_YDS;
> > > + break;
> > > + default:
> > > + break;
> > > + }
> > > }
> > >
> > > /*
> > > diff --git a/drivers/media/platform/rcar-vin/rcar-vin.h b/drivers/media/platform/rcar-vin/rcar-vin.h
> > > index c19d077ce1cb..8396e0e45478 100644
> > > --- a/drivers/media/platform/rcar-vin/rcar-vin.h
> > > +++ b/drivers/media/platform/rcar-vin/rcar-vin.h
> > > @@ -19,6 +19,7 @@
> > > #include <media/v4l2-ctrls.h>
> > > #include <media/v4l2-dev.h>
> > > #include <media/v4l2-device.h>
> > > +#include <media/v4l2-fwnode.h>
> > > #include <media/videobuf2-v4l2.h>
> > >
> > > /* Number of HW buffers */
> > > @@ -92,7 +93,7 @@ struct rvin_video_format {
> > > * @asd: sub-device descriptor for async framework
> > > * @subdev: subdevice matched using async framework
> > > * @mbus_type: media bus type
> > > - * @mbus_flags: media bus configuration flags
> > > + * @bus: media bus parallel configuration
> > > * @source_pad: source pad of remote subdevice
> > > * @sink_pad: sink pad of remote subdevice
> > > *
> > > @@ -102,7 +103,7 @@ struct rvin_parallel_entity {
> > > struct v4l2_subdev *subdev;
> > >
> > > enum v4l2_mbus_type mbus_type;
> > > - unsigned int mbus_flags;
> > > + struct v4l2_fwnode_bus_parallel bus;
>
> I think you could break this change (and the fallout) out to a separate
> patch to make the functional change clearer.

You're often on the side of breaking patches in too small pieces :-) In
this case the patch is small, so I don't think breaking it in two is
required. It would be different if the changes were larger and more
intertwined.

> > >
> > > unsigned int source_pad;
> > > unsigned int sink_pad;

--
Regards,

Laurent Pinchart