From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from metis.ext.pengutronix.de ([85.220.165.71]:53441 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725536AbfHSJB5 (ORCPT ); Mon, 19 Aug 2019 05:01:57 -0400 Date: Mon, 19 Aug 2019 11:01:46 +0200 From: Marco Felsch Subject: Re: [PATCH v7 01/13] dt-bindings: connector: analog: add tv norms property Message-ID: <20190819090146.dguqzy7w7clk67ny@pengutronix.de> References: <20190815115747.24018-1-m.felsch@pengutronix.de> <20190815115747.24018-2-m.felsch@pengutronix.de> <76aeaa4e-4a29-5abe-1af6-fc82958e9530@xs4all.nl> <20190819080904.ch3e3by5seha5ca7@pengutronix.de> <14e1593c-0d90-f242-9ab9-598a1005dbb8@xs4all.nl> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <14e1593c-0d90-f242-9ab9-598a1005dbb8@xs4all.nl> Sender: devicetree-owner@vger.kernel.org To: Hans Verkuil Cc: mchehab@kernel.org, sakari.ailus@linux.intel.com, hans.verkuil@cisco.com, jacopo+renesas@jmondi.org, robh+dt@kernel.org, laurent.pinchart@ideasonboard.com, linux-media@vger.kernel.org, devicetree@vger.kernel.org, kernel@pengutronix.de, Rob Herring List-ID: On 19-08-19 10:39, Hans Verkuil wrote: > On 8/19/19 10:09 AM, Marco Felsch wrote: > > Hi Hans, > > > > On 19-08-16 13:11, Hans Verkuil wrote: > >> On 8/15/19 1:57 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. > >>> > >>> 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 > >>> Reviewed-by: Rob Herring > >>> --- > >>> [1] https://patchwork.kernel.org/cover/10794703/ > >>> > >>> v7: > >>> I kept Robs r b tag because I only changed the example and extended > >>> TVNORM_* macros. > >>> > >>> - fix some style issues > >>> - add TVNORM_NTSC, TVNORM_525_60 and TVNORM_625_50 > >>> > >>> 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 | 72 +++++++++++++++++++ > >>> 2 files changed, 76 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..434e8aa0398b 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 > >> > >> tv -> TV > >> > >>> + all tv norms are allowed. Possible video standards are defined in > >> > >> tv -> TV > > > > Changed both thanks. > > > >> And a more high-level question: I think tvnorm is a very vague name. It's a term > >> used in media, but what does 'norm' mean anyway? 'tv_standards' or 'video_standards' > >> would be a lot more descriptive. > > > > I'm with you *_standards would be more descriptive. Now the question is: > > is it a video or a tv standard? Wikipedia says that SECAM, PAL, NTSC is > > a television standard. So I prefer the 'tv_standards' or better the > > 'tv-standards' approach. > > It's a bit of both, actually. But in the context of S-Video and Composite connectors > it is a video standard. In the context of a tuner/modulator it would be a TV standard. > > I.e. there is no difference between PAL_B and PAL_[GHIDJ] when it comes to S-Video and > Composite connectors, but in the context of a tuner/modulator these defines give > additional information about transmission bands, etc. > > That said, I think video-standards is too vague, but so is tv-standards. How about > sdtv-standards? I think that makes a lot of sense since this is really just for SDTV. Yes, thats a good name. > So tvnorms.h becomes sdtv-standards.h. Of course. > > > >> 'tvnorm' is, I think, a term used only internally in the media subsystem for no > >> clear reason. In the V4L2 spec it talks about 'video standard'. > >> > >> Sorry for being so late with raising this issue. > >> > >>> + 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 | TVNORM_NTSC)>; > >>> > >>> 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..e1275673c4d6 > >>> --- /dev/null > >>> +++ b/include/dt-bindings/media/tvnorms.h > >>> @@ -0,0 +1,72 @@ > >>> +/* SPDX-License-Identifier: GPL-2.0-only or X11 */ > >>> +/* > >>> + * Copyright 2019 Pengutronix, Marco Felsch > >>> + */ > >>> + > >>> +#ifndef _DT_BINDINGS_MEDIA_TVNORMS_H > >>> +#define _DT_BINDINGS_MEDIA_TVNORMS_H > >>> + > >>> +/* One bit for each standard */ > >> > >> I would add a comment here and in videodev2.h where you mention that > >> the two headers should remain in sync. > > > > Yes, good point. > > > >>> +#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_NTSC (TVNORM_NTSC_M |\ > >>> + TVNORM_NTSC_M_JP |\ > >> > >> Add space before \ > >> > >>> + TVNORM_NTSC_M_KR) > >>> + > >>> +#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) > >>> + > >>> +/* Standards for Countries with 60Hz Line frequency */ > >>> +#define TVNORM_525_60 (TVNORM_PAL_M | \ > >>> + TVNORM_PAL_60 | \ > >>> + TVNORM_NTSC | \ > >>> + TVNORM_NTSC_443) > >>> + > >>> +/* Standards for Countries with 50Hz Line frequency */ > >>> +#define TVNORM_625_50 (TVNORM_PAL |\ > >>> + TVNORM_PAL_N |\ > >>> + TVNORM_PAL_Nc |\ > >> > >> Add space before \ > > > > Both space errors fixed. > > > >>> + TVNORM_SECAM) > >>> + > >>> +#endif /* _DT_BINDINGS_MEDIA_TVNORMS_H */ > >>> > >> > >> I was also wondering if this header shouldn't be in include/dt-bindings/display/ > >> since the bindings are also described in 'display'. > > > > That's a good one and I really don't know which is the 'right' place for > > it. Since the standard has nothing to do with a display I would keep it > > within media. But the radeon [1] gpu uses the stds too. So I really > > don't know which place is better. > > Move it to display: that matches where the documentation is. Okay. > > Note that this means that _DT_BINDINGS_MEDIA_TVNORMS_H also becomes > _DT_BINDINGS_DISPLAY_TVNORMS_H (or DISPLAY_SDTV_STANDARDS_H). Yes. Last question. I replaced TVNORM_* by TV_STD_*. Should I move to SDTV_STD_* too? Regards, Marco > Regards, > > Hans > > > > > [1] drivers/gpu/drm/radeon/radeon_mode.h. > > > > Regards, > > Marco > > > >> Regards, > >> > >> Hans > >> > > > > -- 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 |