Hi Mauro, Hans, thanks for the review. On 19-05-14 15:11, Mauro Carvalho Chehab wrote: > Em Mon, 6 May 2019 12:01:06 +0200 > Hans Verkuil <hverkuil@xxxxxxxxx> escreveu: > > > On 4/15/19 2:44 PM, Marco Felsch wrote: > > > Some connectors no matter if in- or output supports only a limited > > > range of tv norms. It doesn't matter if the hardware behind that > > > connector supports more than the listed formats since the users are > > > restriced by a label e.g. to plug only a camera into this connector > > > which uses the PAL format. > > > > For S-Video and Composite connectors there are really just two formats > > to consider: 50 and 60 Hz. I.e. there is no difference between PAL > > and SECAM. Only for tuners/modulators does this matter. > > > > So it is a good idea to add TVNORM_525_60, TVNORM_625_50 to tvnorms.h. Of course I can add this ones. With Mauro's concerns below do you still think that it is a good idea to adapt the example? Regards, Marco > > In the various bindings examples I would recommend that you use > > TVNORM_525_60 or TVNORM_625_50 rather than e.g. PAL_M since that's what > > you would use in practice for Composite/S-Video. > > Hans, that could be true for component video, but for S-Video and > Composite, you need to tell the demod how the color sub-carrier is > encoded, and what's its frequency, or otherwise it won't work. > > There are plenty of equipments in Brazil that have both NTSC/M and > PAL/M (and a few with PAL/N') output. All those formats are 60Hz. > > Colors are only decoded by tvp5150 and other demods if it is set > to the right color format (PAL or NTSC) and to the right line > frequency (60Hz) [1]. Also, some decoders are very sensitive to the > chroma sub-carrier frequency. That's the case of tvp5150. > > [1] Or - when supported by the hardware - if the demod is set to > automatic mode. > > Automatic mode usually doesn't work well with PAL/M and PAL/N'. > > The problem is related to the sub-carrier frequency: both > PAL/N' (used only on Paraguay) and NTSC/M have the same > frequency; PAL/M has a close but different frequency for the > color sub-carrier. > > Most decoders use the frequency of the chroma sub-carrier in > order to switch between NTSC/M nd PAL/M. So, auto-detection > usually fails with PAL/N', as such detectors understand it > as NTSC. > > Worse than that, it is not uncommon to have pseudo-PAL-M devices > that were made for the US market, and received a conversion > to PAL, with envolves adding a small board with a NTSC->PAL converter. > As most TV sets used in this part of the world are designed to > work both with PAL/M and PAL/N' (by using a broader notch filter), > to make the hardware cheaper, lots of manufacturers just > change the modulation on encoders, while keeping the NTSC XTAL. > So, in practice, such devices, sold as "PAL/M" are actually PAL/N'. > A significant amount of old VCRs and DVD devices found in Brazil > are actually PAL/N'. The same applies to game consoles. > > Btw, the main reason for having analog video streams here nowadays > is to copy old videos from VCRs and encode them digitally or to > record games from game consoles. > > > > > Regards, > > > > Hans > > > > > > > > This patch adds the capability to describe such limitation within the > > > firmware. There are no format restrictions if the property isn't > > > present, so it's completely backward compatible. > > > > > > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx> > > > Reviewed-by: Rob Herring <robh@xxxxxxxxxx> > > > --- > > > [1] https://patchwork.kernel.org/cover/10794703/ > > > > > > v6: > > > - tvnorms.h: use tabs instead of spaces > > > - tvnorms.h: add TVNORM_PAL and TVNORM_SECAM > > > - tvnorms.h: drop rarely used TVNORM_ATSC_* norms > > > > > > v2-v4: > > > - nothing since the patch was squashed from series [1] into this > > > series. > > > > > > .../display/connector/analog-tv-connector.txt | 4 ++ > > > include/dt-bindings/media/tvnorms.h | 56 +++++++++++++++++++ > > > 2 files changed, 60 insertions(+) > > > create mode 100644 include/dt-bindings/media/tvnorms.h > > > > > > diff --git a/Documentation/devicetree/bindings/display/connector/analog-tv-connector.txt b/Documentation/devicetree/bindings/display/connector/analog-tv-connector.txt > > > index 0c0970c210ab..346f8937a0b7 100644 > > > --- a/Documentation/devicetree/bindings/display/connector/analog-tv-connector.txt > > > +++ b/Documentation/devicetree/bindings/display/connector/analog-tv-connector.txt > > > @@ -6,6 +6,9 @@ Required properties: > > > > > > Optional properties: > > > - label: a symbolic name for the connector > > > +- tvnorms: limit the supported tv norms on a connector to the given ones else > > > + all tv norms are allowed. Possible video standards are defined in > > > + include/dt-bindings/media/tvnorms.h. > > > > > > Required nodes: > > > - Video port for TV input > > > @@ -16,6 +19,7 @@ Example > > > tv: connector { > > > compatible = "composite-video-connector"; > > > label = "tv"; > > > + tvnorms = <(TVNORM_PAL_M | TVNORM_NTSC_M)>; > > > > > > port { > > > tv_connector_in: endpoint { > > > diff --git a/include/dt-bindings/media/tvnorms.h b/include/dt-bindings/media/tvnorms.h > > > new file mode 100644 > > > index 000000000000..058ab8414145 > > > --- /dev/null > > > +++ b/include/dt-bindings/media/tvnorms.h > > > @@ -0,0 +1,56 @@ > > > +/* SPDX-License-Identifier: GPL-2.0-only or X11 */ > > > +/* > > > + * Copyright 2019 Pengutronix, Marco Felsch <kernel@xxxxxxxxxxxxxx> > > > + */ > > > + > > > +#ifndef _DT_BINDINGS_MEDIA_TVNORMS_H > > > +#define _DT_BINDINGS_MEDIA_TVNORMS_H > > > + > > > +/* one bit for each */ > > > +#define TVNORM_PAL_B 0x00000001 > > > +#define TVNORM_PAL_B1 0x00000002 > > > +#define TVNORM_PAL_G 0x00000004 > > > +#define TVNORM_PAL_H 0x00000008 > > > +#define TVNORM_PAL_I 0x00000010 > > > +#define TVNORM_PAL_D 0x00000020 > > > +#define TVNORM_PAL_D1 0x00000040 > > > +#define TVNORM_PAL_K 0x00000080 > > > + > > > +#define TVNORM_PAL (TVNORM_PAL_B | \ > > > + TVNORM_PAL_B1 | \ > > > + TVNORM_PAL_G | \ > > > + TVNORM_PAL_H | \ > > > + TVNORM_PAL_I | \ > > > + TVNORM_PAL_D | \ > > > + TVNORM_PAL_D1 | \ > > > + TVNORM_PAL_K) > > > + > > > +#define TVNORM_PAL_M 0x00000100 > > > +#define TVNORM_PAL_N 0x00000200 > > > +#define TVNORM_PAL_Nc 0x00000400 > > > +#define TVNORM_PAL_60 0x00000800 > > > + > > > +#define TVNORM_NTSC_M 0x00001000 /* BTSC */ > > > +#define TVNORM_NTSC_M_JP 0x00002000 /* EIA-J */ > > > +#define TVNORM_NTSC_443 0x00004000 > > > +#define TVNORM_NTSC_M_KR 0x00008000 /* FM A2 */ > > > + > > > +#define TVNORM_SECAM_B 0x00010000 > > > +#define TVNORM_SECAM_D 0x00020000 > > > +#define TVNORM_SECAM_G 0x00040000 > > > +#define TVNORM_SECAM_H 0x00080000 > > > +#define TVNORM_SECAM_K 0x00100000 > > > +#define TVNORM_SECAM_K1 0x00200000 > > > +#define TVNORM_SECAM_L 0x00400000 > > > +#define TVNORM_SECAM_LC 0x00800000 > > > + > > > +#define TVNORM_SECAM (TVNORM_SECAM_B | \ > > > + TVNORM_SECAM_D | \ > > > + TVNORM_SECAM_G | \ > > > + TVNORM_SECAM_H | \ > > > + TVNORM_SECAM_K | \ > > > + TVNORM_SECAM_K1 | \ > > > + TVNORM_SECAM_L | \ > > > + TVNORM_SECAM_LC) > > > + > > > +#endif /* _DT_BINDINGS_MEDIA_TVNORMS_H */ > > Patch looks good to me. > > Thanks, > Mauro > -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
