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From: Linus Walleij <linus.walleij@linaro.org>
To: Jagan Teki <jagan@amarulasolutions.com>
Cc: "Thierry Reding" <thierry.reding@gmail.com>,
	"Sam Ravnborg" <sam@ravnborg.org>,
	dri-devel <dri-devel@lists.freedesktop.org>,
	phone-devel@vger.kernel.org,
	"Douglas Anderson" <dianders@chromium.org>,
	"Noralf Trønnes" <noralf@tronnes.org>
Subject: Re: [PATCH 2/2 v3] drm/panel: ws2401: Add driver for WideChips WS2401
Date: Fri, 9 Jul 2021 17:03:12 +0200	[thread overview]
Message-ID: <CACRpkdaSo_+z3tJzR8A5B9HhDVUHeutW9AHash9YgVo9SC+ARA@mail.gmail.com> (raw)
In-Reply-To: <CAMty3ZCjciURnUJnTOPDQOSaiDVRneJoe=w9U==73Jt=Wd895w@mail.gmail.com>

On Fri, Jul 9, 2021 at 11:25 AM Jagan Teki <jagan@amarulasolutions.com> wrote:

> > +       /* Assert reset >=1 ms */
> > +       gpiod_set_value_cansleep(ws->reset, 1);
> > +       usleep_range(1000, 5000);
> > +       /* De-assert reset */
> > +       gpiod_set_value_cansleep(ws->reset, 0);
> > +       /* Wait >= 10 ms */
> > +       msleep(10);
> > +       dev_dbg(ws->dev, "de-asserted RESET\n");
>
> Just a small comment, are these delays are as per init sequence
> mentioned in datasheet?

As so often with Samsung mobile displays there is no datasheet.

These delays are in the product source code tree for the
GT-I8160 (Codina) mobile phone, actually in the glue integration
code. WideChips were acquired by some other firm and do not
exist anymore so I can't ask them, and asking Samsung for anything
else than source code doesn't work either. (I have tried.)

Yours,
Linus Walleij

WARNING: multiple messages have this Message-ID (diff)
From: Linus Walleij <linus.walleij@linaro.org>
To: Jagan Teki <jagan@amarulasolutions.com>
Cc: "Douglas Anderson" <dianders@chromium.org>,
	dri-devel <dri-devel@lists.freedesktop.org>,
	"Noralf Trønnes" <noralf@tronnes.org>,
	"Thierry Reding" <thierry.reding@gmail.com>,
	phone-devel@vger.kernel.org, "Sam Ravnborg" <sam@ravnborg.org>
Subject: Re: [PATCH 2/2 v3] drm/panel: ws2401: Add driver for WideChips WS2401
Date: Fri, 9 Jul 2021 17:03:12 +0200	[thread overview]
Message-ID: <CACRpkdaSo_+z3tJzR8A5B9HhDVUHeutW9AHash9YgVo9SC+ARA@mail.gmail.com> (raw)
In-Reply-To: <CAMty3ZCjciURnUJnTOPDQOSaiDVRneJoe=w9U==73Jt=Wd895w@mail.gmail.com>

On Fri, Jul 9, 2021 at 11:25 AM Jagan Teki <jagan@amarulasolutions.com> wrote:

> > +       /* Assert reset >=1 ms */
> > +       gpiod_set_value_cansleep(ws->reset, 1);
> > +       usleep_range(1000, 5000);
> > +       /* De-assert reset */
> > +       gpiod_set_value_cansleep(ws->reset, 0);
> > +       /* Wait >= 10 ms */
> > +       msleep(10);
> > +       dev_dbg(ws->dev, "de-asserted RESET\n");
>
> Just a small comment, are these delays are as per init sequence
> mentioned in datasheet?

As so often with Samsung mobile displays there is no datasheet.

These delays are in the product source code tree for the
GT-I8160 (Codina) mobile phone, actually in the glue integration
code. WideChips were acquired by some other firm and do not
exist anymore so I can't ask them, and asking Samsung for anything
else than source code doesn't work either. (I have tried.)

Yours,
Linus Walleij

  reply	other threads:[~2021-07-09 15:03 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-07 23:43 [PATCH 1/2 v3] drm/panel: Add DT bindings for Samsung LMS380KF01 Linus Walleij
2021-07-07 23:43 ` Linus Walleij
2021-07-07 23:43 ` [PATCH 2/2 v3] drm/panel: ws2401: Add driver for WideChips WS2401 Linus Walleij
2021-07-07 23:43   ` Linus Walleij
2021-07-08 14:48   ` Noralf Trønnes
2021-07-08 20:04   ` Doug Anderson
2021-07-08 20:04     ` Doug Anderson
2021-07-09  9:25   ` Jagan Teki
2021-07-09  9:25     ` Jagan Teki
2021-07-09 15:03     ` Linus Walleij [this message]
2021-07-09 15:03       ` Linus Walleij
2021-07-09 18:01   ` Sam Ravnborg
2021-07-08 20:04 ` [PATCH 1/2 v3] drm/panel: Add DT bindings for Samsung LMS380KF01 Doug Anderson
2021-07-08 20:04   ` Doug Anderson
2021-07-09 17:33 ` Sam Ravnborg
2021-07-12 17:18 ` Rob Herring
2021-07-12 17:18   ` Rob Herring

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