All of lore.kernel.org
 help / color / mirror / Atom feed
From: laurent.pinchart@ideasonboard.com (Laurent Pinchart)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/6] dt-bindings: display: add data-enable polarity property
Date: Wed, 05 Sep 2018 23:50:25 +0300	[thread overview]
Message-ID: <6830776.vZAoroGVFQ@avalon> (raw)
In-Reply-To: <e708c5bac502e60a2eeb685fddf67042@agner.ch>

Hi Stefan,

On Wednesday, 5 September 2018 21:10:08 EEST Stefan Agner wrote:
> On 05.09.2018 00:07, Laurent Pinchart wrote:
> > On Wednesday, 5 September 2018 08:21:10 EEST Stefan Agner wrote:
> >> Allow to specify the data-enable polarity required by a dumb VGA
> >> DAC converting parallel RGB to VGA.
> >> 
> >> Signed-off-by: Stefan Agner <stefan@agner.ch>
> >> ---
> >> 
> >>  .../devicetree/bindings/display/bridge/dumb-vga-dac.txt          | 1 +
> >>  1 file changed, 1 insertion(+)
> >> 
> >> diff --git
> >> a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt index
> >> 164cbb15f04c..adbd2ca0af2f 100644
> >> --- a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> +++ b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> @@ -18,6 +18,7 @@ graph bindings specified in
> >> Documentation/devicetree/bindings/graph.txt.
> >> 
> >>  Optional properties:
> >>  - vdd-supply: Power supply for DAC
> >> 
> >> +- de-active: data-enable pulse is active low/high/ignored
> > 
> > Which value corresponds to low, high and ignored ?
> 
> The wording is taken from
> Documentation/devicetree/bindings/display/panel/display-timing.txt. But
> I agree, not very useful.
> 
> 0 is low active, 1 is high active, and none is using driver defaults.
> 
> How about:
> - de-active: data-enable pulse is 0=active low/1=active high

The data enable signal isn't really a pulse. I would word this as

- de-active: Polarity of the data enable signal. 0 for active low, 1 for 
active high, unset for system-specific defaults.

> >>  Example
> >>  -------

-- 
Regards,

Laurent Pinchart

WARNING: multiple messages have this Message-ID (diff)
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Stefan Agner <stefan@agner.ch>
Cc: mark.rutland@arm.com, devicetree@vger.kernel.org,
	max.krummenacher@toradex.com, kernel@pengutronix.de,
	marcel.ziswiler@toradex.com, airlied@linux.ie,
	linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
	robh+dt@kernel.org, linux-imx@nxp.com, fabio.estevam@nxp.com,
	sean@poorly.run, shawnguo@kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 3/6] dt-bindings: display: add data-enable polarity property
Date: Wed, 05 Sep 2018 23:50:25 +0300	[thread overview]
Message-ID: <6830776.vZAoroGVFQ@avalon> (raw)
In-Reply-To: <e708c5bac502e60a2eeb685fddf67042@agner.ch>

Hi Stefan,

On Wednesday, 5 September 2018 21:10:08 EEST Stefan Agner wrote:
> On 05.09.2018 00:07, Laurent Pinchart wrote:
> > On Wednesday, 5 September 2018 08:21:10 EEST Stefan Agner wrote:
> >> Allow to specify the data-enable polarity required by a dumb VGA
> >> DAC converting parallel RGB to VGA.
> >> 
> >> Signed-off-by: Stefan Agner <stefan@agner.ch>
> >> ---
> >> 
> >>  .../devicetree/bindings/display/bridge/dumb-vga-dac.txt          | 1 +
> >>  1 file changed, 1 insertion(+)
> >> 
> >> diff --git
> >> a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt index
> >> 164cbb15f04c..adbd2ca0af2f 100644
> >> --- a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> +++ b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> @@ -18,6 +18,7 @@ graph bindings specified in
> >> Documentation/devicetree/bindings/graph.txt.
> >> 
> >>  Optional properties:
> >>  - vdd-supply: Power supply for DAC
> >> 
> >> +- de-active: data-enable pulse is active low/high/ignored
> > 
> > Which value corresponds to low, high and ignored ?
> 
> The wording is taken from
> Documentation/devicetree/bindings/display/panel/display-timing.txt. But
> I agree, not very useful.
> 
> 0 is low active, 1 is high active, and none is using driver defaults.
> 
> How about:
> - de-active: data-enable pulse is 0=active low/1=active high

The data enable signal isn't really a pulse. I would word this as

- de-active: Polarity of the data enable signal. 0 for active low, 1 for 
active high, unset for system-specific defaults.

> >>  Example
> >>  -------

-- 
Regards,

Laurent Pinchart



_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel

WARNING: multiple messages have this Message-ID (diff)
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Stefan Agner <stefan@agner.ch>
Cc: linus.walleij@linaro.org, airlied@linux.ie, robh+dt@kernel.org,
	mark.rutland@arm.com, shawnguo@kernel.org,
	s.hauer@pengutronix.de, p.zabel@pengutronix.de,
	kernel@pengutronix.de, fabio.estevam@nxp.com, linux-imx@nxp.com,
	architt@codeaurora.org, a.hajda@samsung.com, gustavo@padovan.org,
	maarten.lankhorst@linux.intel.com, sean@poorly.run,
	marcel.ziswiler@toradex.com, max.krummenacher@toradex.com,
	dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/6] dt-bindings: display: add data-enable polarity property
Date: Wed, 05 Sep 2018 23:50:25 +0300	[thread overview]
Message-ID: <6830776.vZAoroGVFQ@avalon> (raw)
In-Reply-To: <e708c5bac502e60a2eeb685fddf67042@agner.ch>

Hi Stefan,

On Wednesday, 5 September 2018 21:10:08 EEST Stefan Agner wrote:
> On 05.09.2018 00:07, Laurent Pinchart wrote:
> > On Wednesday, 5 September 2018 08:21:10 EEST Stefan Agner wrote:
> >> Allow to specify the data-enable polarity required by a dumb VGA
> >> DAC converting parallel RGB to VGA.
> >> 
> >> Signed-off-by: Stefan Agner <stefan@agner.ch>
> >> ---
> >> 
> >>  .../devicetree/bindings/display/bridge/dumb-vga-dac.txt          | 1 +
> >>  1 file changed, 1 insertion(+)
> >> 
> >> diff --git
> >> a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt index
> >> 164cbb15f04c..adbd2ca0af2f 100644
> >> --- a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> +++ b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> >> @@ -18,6 +18,7 @@ graph bindings specified in
> >> Documentation/devicetree/bindings/graph.txt.
> >> 
> >>  Optional properties:
> >>  - vdd-supply: Power supply for DAC
> >> 
> >> +- de-active: data-enable pulse is active low/high/ignored
> > 
> > Which value corresponds to low, high and ignored ?
> 
> The wording is taken from
> Documentation/devicetree/bindings/display/panel/display-timing.txt. But
> I agree, not very useful.
> 
> 0 is low active, 1 is high active, and none is using driver defaults.
> 
> How about:
> - de-active: data-enable pulse is 0=active low/1=active high

The data enable signal isn't really a pulse. I would word this as

- de-active: Polarity of the data enable signal. 0 for active low, 1 for 
active high, unset for system-specific defaults.

> >>  Example
> >>  -------

-- 
Regards,

Laurent Pinchart




  reply	other threads:[~2018-09-05 20:50 UTC|newest]

Thread overview: 72+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-09-05  5:21 [PATCH 1/6] drm/bridge: use bus flags in bridge timings Stefan Agner
2018-09-05  5:21 ` Stefan Agner
2018-09-05  5:21 ` Stefan Agner
2018-09-05  5:21 ` [PATCH 2/6] drm/bridge: allow to specify data-enable polarity Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21 ` [PATCH 3/6] dt-bindings: display: add data-enable polarity property Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  7:07   ` Laurent Pinchart
2018-09-05  7:07     ` Laurent Pinchart
2018-09-05  7:07     ` Laurent Pinchart
2018-09-05 18:10     ` Stefan Agner
2018-09-05 18:10       ` Stefan Agner
2018-09-05 18:10       ` Stefan Agner
2018-09-05 20:50       ` Laurent Pinchart [this message]
2018-09-05 20:50         ` Laurent Pinchart
2018-09-05 20:50         ` Laurent Pinchart
2018-09-05  5:21 ` [PATCH 4/6] drm/imx: support handling bridge timings bus flags Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21 ` [PATCH 5/6] ARM: dts: imx6qdl-apalis: add VGA support Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21 ` [PATCH 6/6] ARM: dts: imx6qdl-apalis: add GPIO I2C node for DDC Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  5:21   ` Stefan Agner
2018-09-05  7:06 ` [PATCH 1/6] drm/bridge: use bus flags in bridge timings Laurent Pinchart
2018-09-05  7:06   ` Laurent Pinchart
2018-09-05  7:44   ` Laurent Pinchart
2018-09-05  7:44     ` Laurent Pinchart
2018-09-05  7:44     ` Laurent Pinchart
2018-09-05 18:32     ` Stefan Agner
2018-09-05 18:32       ` Stefan Agner
2018-09-05 18:32       ` Stefan Agner
2018-09-06 11:07       ` Linus Walleij
2018-09-06 11:07         ` Linus Walleij
2018-09-06 11:07         ` Linus Walleij
2018-09-06 12:25         ` Laurent Pinchart
2018-09-06 12:25           ` Laurent Pinchart
2018-09-06 12:25           ` Laurent Pinchart
2018-09-06 16:48           ` Stefan Agner
2018-09-06 16:48             ` Stefan Agner
2018-09-06 16:48             ` Stefan Agner
2018-09-06 16:54             ` Laurent Pinchart
2018-09-06 16:54               ` Laurent Pinchart
2018-09-06 16:54               ` Laurent Pinchart
2018-09-06 17:27               ` Stefan Agner
2018-09-06 17:27                 ` Stefan Agner
2018-09-06 17:27                 ` Stefan Agner
2018-09-06 20:25         ` Stefan Agner
2018-09-06 20:25           ` Stefan Agner
2018-09-06 20:25           ` Stefan Agner
2018-09-07  7:10           ` Linus Walleij
2018-09-07  7:10             ` Linus Walleij
2018-09-07  7:10             ` Linus Walleij
2018-09-07 18:25             ` Stefan Agner
2018-09-07 18:25               ` Stefan Agner
2018-09-07 18:25               ` Stefan Agner
2018-09-14  9:55               ` Laurent Pinchart
2018-09-14  9:55                 ` Laurent Pinchart
2018-09-14  9:55                 ` Laurent Pinchart
2018-09-14  9:49           ` Laurent Pinchart
2018-09-14  9:49             ` Laurent Pinchart
2018-09-14  9:49             ` Laurent Pinchart
2018-09-14  9:57             ` Laurent Pinchart
2018-09-14  9:57               ` Laurent Pinchart
2018-09-14  9:57               ` Laurent Pinchart
2018-09-19  7:03             ` Stefan Agner
2018-09-19  7:03               ` Stefan Agner
2018-09-19  7:03               ` Stefan Agner
  -- strict thread matches above, loose matches on Subject: below --
2018-09-05 18:00 Stefan Agner
2018-09-05 18:00 ` [PATCH 3/6] dt-bindings: display: add data-enable polarity property Stefan Agner

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6830776.vZAoroGVFQ@avalon \
    --to=laurent.pinchart@ideasonboard.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.