public inbox for linux-arm-kernel@lists.infradead.org 
 help / color / mirror / Atom feed
From: t.figa@samsung•com (Tomasz Figa)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 2/2] ARM: dts: ODROID i2c improvements
Date: Wed, 16 Jul 2014 14:34:59 +0200	[thread overview]
Message-ID: <53C67173.9060006@samsung.com> (raw)
In-Reply-To: <1405500606-5752-2-git-send-email-drake@endlessm.com>

On 16.07.2014 10:50, Daniel Drake wrote:
> Increase max i2c bus frequency beyond the default for faster
> data transfers. According to the manual, these faster speeds are
> only available when the board is wired up the right way. In this case,
> the vendor kernel has run at this speed for a long time.
> 
> sda-delay is needed for talking to RTC on PMIC, otherwise the i2c
> controller never sees an ACK. Strangely the other PMIC i2c slave (the
> main one) works fine even without this delay. I Chose value 100 to
> match the vendor kernel.
> 
> Signed-off-by: Daniel Drake <drake@endlessm•com>
> ---
>  arch/arm/boot/dts/exynos4412-odroid-common.dtsi | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> index cb6f55f..adadaf9 100644
> --- a/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> +++ b/arch/arm/boot/dts/exynos4412-odroid-common.dtsi
> @@ -134,6 +134,8 @@
>  	i2c at 13860000 {
>  		pinctrl-0 = <&i2c0_bus>;
>  		pinctrl-names = "default";
> +		samsung,i2c-sda-delay = <100>;
> +		samsung,i2c-max-bus-freq = <400000>;
>  		status = "okay";
>  
>  		usb3503: usb3503 at 08 {
> 

Reviewed-by: Tomasz Figa <t.figa@samsung•com>

--
Best regards,
Tomasz

  reply	other threads:[~2014-07-16 12:34 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-16  8:50 [PATCH 1/2] ARM: dts: Enable PMIC interrupts on ODROID Daniel Drake
2014-07-16  8:50 ` [PATCH 2/2] ARM: dts: ODROID i2c improvements Daniel Drake
2014-07-16 12:34   ` Tomasz Figa [this message]
2014-08-12 13:11   ` Tomeu Vizoso
2014-07-16 12:34 ` [PATCH 1/2] ARM: dts: Enable PMIC interrupts on ODROID Tomasz Figa
2014-08-12 13:06 ` Tomeu Vizoso
2014-08-18 16:43   ` Kukjin Kim
2014-08-19  9:57     ` Bartlomiej Zolnierkiewicz
2014-08-19 10:15       ` Javier Martinez Canillas
2014-08-19 20:18         ` Olof Johansson
2014-08-22 10:39           ` Kukjin Kim
2014-08-24 18:32             ` Olof Johansson

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=53C67173.9060006@samsung.com \
    --to=t.figa@samsung$(echo .)com \
    --cc=linux-arm-kernel@lists$(echo .)infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox