From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Subject: Re: [PATCH v7 01/13] dt-bindings: connector: analog: add tv norms property 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> <20190819081850.e3v7yyjx7onpp3al@pengutronix.de> From: Hans Verkuil Message-ID: Date: Mon, 19 Aug 2019 10:41:07 +0200 MIME-Version: 1.0 In-Reply-To: <20190819081850.e3v7yyjx7onpp3al@pengutronix.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit To: Marco Felsch Cc: devicetree@vger.kernel.org, kernel@pengutronix.de, Rob Herring , robh+dt@kernel.org, jacopo+renesas@jmondi.org, laurent.pinchart@ideasonboard.com, sakari.ailus@linux.intel.com, hans.verkuil@cisco.com, mchehab@kernel.org, linux-media@vger.kernel.org List-ID: On 8/19/19 10:18 AM, Marco Felsch wrote: > Hi, > > On 19-08-19 10:09, 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. > > While on it I noticed that the v4l_std_id is u64. Should we add the > support for u64 here too? No need. SDTV standards are frozen (i.e. no new standards will ever be added), so everything fits nicely in 32 bits. Regards, Hans > > Regards, > Marco > >>> '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. >> >> [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 | >> >> >