Hi Laurent, On 19-08-15 16:02, Laurent Pinchart wrote: > Hi Marco, > > On Thu, Aug 15, 2019 at 02:50:02PM +0200, Marco Felsch wrote: > > On 19-08-15 15:33, Laurent Pinchart wrote: > > > On Fri, Aug 09, 2019 at 07:58:09AM +0200, Marco Felsch wrote: > > >> On 19-05-16 19:27, Laurent Pinchart wrote: > > >>> On Mon, Apr 15, 2019 at 02:44:01PM +0200, 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. > > >>> > > >>> Why is this needed ? It's not really a hardware property, is it ? What's > > >>> the use case ? > > >> > > >> Cause some hardware only support a limited range of formats to that > > >> connector. Of course it is a hardware property. For example if a > > >> customer wants to limit a connector to a specifc norm because the > > >> hardware behind that connector only supports that format or is > > >> restricted to that format. > > > > > > Then it should be a DT property of the hardware behind that connector > > > (or information hardcoded directly into that driver), shouldn't it ? > > > > Why? The connector is the limiting factor and not the decoder/bridge > > device behind that. Let me explain it a bit more in detail. Our customer > > sells hardware boxes and cameras. The camera is connected to the box > > using a custom plug. So it's guaranteed that only their cameras can be > > connected to. Also the camera they are using supports only PAL. So the > > PAL signal is the only one which can be received on that connector. The > > TVP itself supports more than just PAL signals and has multiple inputs. > > So there can be the use case that a hardware box supports two physical > > connectors: e.g. connector-PAL, connector-NTSC. The TVP should be > > limited to PAL signals if the connector-PAL is active or limited to NTSC > > if the connector-NTSC is active. > > > > Hopefully you see now why we should model it on the connector side and > > not on the device behind that connector. > > So it essentially means that if someone connects an NTSC camera on the > PAL input with the same custom connector, the hardware will support it, > right ? I don't think it's a hardware limitation of the connector in > that case :-) And I don't think it belongs to DT. Userspace is probably > where I would handle this type of policy. What you describe here would be a 'user hack' because our customer sells only PAL cameras. I think it is a connector limitation because the connector can be labeld with "PAL only" and is rectangle and there can be a round "NTSC only" connector. IMHO this is a hardware limiting factor and no one would expect that a NTSC camera is working on a "PAL only" labeld connector. Regards, Marco > > >>>> 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 */ > > -- > Regards, > > Laurent Pinchart > -- 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 |
