All of lore.kernel.org
 help / color / mirror / Atom feed
From: Doug Anderson <dianders@chromium.org>
To: Heiko Stuebner <heiko@sntech.de>
Cc: Chris Zhong <zyw@rock-chips.com>,
	Addy Ke <addy.ke@rock-chips.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-rockchip@lists.infradead.org,
	Doug Anderson <dianders@chromium.org>,
	robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com,
	ijc+devicetree@hellion.org.uk, galak@codeaurora.org,
	linux@arm.linux.org.uk, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH] ARM: dts: Switch i2c0 to 400kHz on rk3288-evb-rk808
Date: Wed, 10 Sep 2014 21:30:15 -0700	[thread overview]
Message-ID: <1410409815-22200-1-git-send-email-dianders@chromium.org> (raw)

We should be able to talk to the PMIC at 400kHz.  No need to talk at
the slow 100kHz.

As measured by ftrace (with a bunch of extra patches, since cpufreq
for rk808 hasn't landed yet):
  before this change: cpu0_set_target() => ~500us
  after this change:  cpu0_set_target() => ~300us

Signed-off-by: Doug Anderson <dianders@chromium.org>
---
 arch/arm/boot/dts/rk3288-evb-rk808.dts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/rk3288-evb-rk808.dts b/arch/arm/boot/dts/rk3288-evb-rk808.dts
index 36db177..ff522f8 100644
--- a/arch/arm/boot/dts/rk3288-evb-rk808.dts
+++ b/arch/arm/boot/dts/rk3288-evb-rk808.dts
@@ -18,6 +18,7 @@
 };
 
 &i2c0 {
+	clock-frequency = <400000>;
 	status = "okay";
 
 	rk808: pmic@1b {
-- 
2.1.0.rc2.206.gedb03e5


WARNING: multiple messages have this Message-ID
From: dianders@chromium.org (Doug Anderson)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: dts: Switch i2c0 to 400kHz on rk3288-evb-rk808
Date: Wed, 10 Sep 2014 21:30:15 -0700	[thread overview]
Message-ID: <1410409815-22200-1-git-send-email-dianders@chromium.org> (raw)

We should be able to talk to the PMIC at 400kHz.  No need to talk at
the slow 100kHz.

As measured by ftrace (with a bunch of extra patches, since cpufreq
for rk808 hasn't landed yet):
  before this change: cpu0_set_target() => ~500us
  after this change:  cpu0_set_target() => ~300us

Signed-off-by: Doug Anderson <dianders@chromium.org>
---
 arch/arm/boot/dts/rk3288-evb-rk808.dts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/rk3288-evb-rk808.dts b/arch/arm/boot/dts/rk3288-evb-rk808.dts
index 36db177..ff522f8 100644
--- a/arch/arm/boot/dts/rk3288-evb-rk808.dts
+++ b/arch/arm/boot/dts/rk3288-evb-rk808.dts
@@ -18,6 +18,7 @@
 };
 
 &i2c0 {
+	clock-frequency = <400000>;
 	status = "okay";
 
 	rk808: pmic at 1b {
-- 
2.1.0.rc2.206.gedb03e5

             reply	other threads:[~2014-09-11  4:30 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-09-11  4:30 Doug Anderson [this message]
2014-09-11  4:30 ` Doug Anderson
2014-09-11  9:17 ` Addy
2014-09-11  9:17   ` Addy
2014-09-11  9:17   ` Addy
2014-09-11  9:23 ` Heiko Stübner
2014-09-11  9:23   ` Heiko Stübner

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=1410409815-22200-1-git-send-email-dianders@chromium.org \
    --to=dianders@chromium.org \
    --cc=addy.ke@rock-chips.com \
    --cc=devicetree@vger.kernel.org \
    --cc=galak@codeaurora.org \
    --cc=heiko@sntech.de \
    --cc=ijc+devicetree@hellion.org.uk \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-rockchip@lists.infradead.org \
    --cc=linux@arm.linux.org.uk \
    --cc=mark.rutland@arm.com \
    --cc=pawel.moll@arm.com \
    --cc=robh+dt@kernel.org \
    --cc=zyw@rock-chips.com \
    --subject='Re: [PATCH] ARM: dts: Switch i2c0 to 400kHz on rk3288-evb-rk808' \
    /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

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.