From: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>
To: Addy Ke <addy.ke-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
Cc: max.schwarz-BGeptl67XyCzQB+pC5nmwQ@public.gmane.org,
heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org,
olof-nZhT3qVonbNeoWH0uzbU5w@public.gmane.org,
dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org,
linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
cf-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
xjq-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
huangtao-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
zyw-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
yzq-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
hj-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
kever.yang-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
hl-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
caesar.wang-TNX95d0MmH7DzftRWevZcw@public.gmane.org,
zhengsq-TNX95d0MmH7DzftRWevZcw@public.gmane.org
Subject: Re: [PATCH v6] i2c: rk3x: adjust the LOW divison based on characteristics of SCL
Date: Mon, 10 Nov 2014 15:58:52 +0100 [thread overview]
Message-ID: <20141110145852.GD10422@katana> (raw)
In-Reply-To: <1413266961-3859-1-git-send-email-addy.ke-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
[-- Attachment #1: Type: text/plain, Size: 1015 bytes --]
On Tue, Oct 14, 2014 at 02:09:21PM +0800, Addy Ke wrote:
> As show in I2C specification:
> - Standard-mode: the minimum HIGH period of the scl clock is 4.0us
> the minimum LOW period of the scl clock is 4.7us
> - Fast-mode: the minimum HIGH period of the scl clock is 0.6us
> the minimum LOW period of the scl clock is 1.3us
>
> I have measured i2c SCL waveforms in fast-mode by oscilloscope
> on rk3288-pinky board. the LOW period of the scl clock is 1.3us.
> It is so critical that we must adjust LOW division to increase
> the LOW period of the scl clock.
>
> Thanks Doug for the suggestion about division formulas.
>
> Tested-by: Heiko Stuebner <heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org>
> Reviewed-by: Doug Anderson <dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
> Tested-by: Doug Anderson <dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org>
> Signed-off-by: Addy Ke <addy.ke-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
Applied to for-next, thanks!
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
prev parent reply other threads:[~2014-11-10 14:58 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-13 2:44 [PATCH v5] i2c: rk3x: adjust the LOW divison based on characteristics of SCL Addy Ke
[not found] ` <1413168244-3553-1-git-send-email-addy.ke-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
2014-10-13 8:34 ` Max Schwarz
2014-10-14 6:09 ` [PATCH v6] " Addy Ke
[not found] ` <1413266961-3859-1-git-send-email-addy.ke-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
2014-10-14 22:42 ` Max Schwarz
2014-11-10 14:58 ` Wolfram Sang [this message]
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=20141110145852.GD10422@katana \
--to=wsa-z923lk4zbo2bacvfa/9k2g@public.gmane.org \
--cc=addy.ke-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=caesar.wang-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=cf-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=dianders-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org \
--cc=heiko-4mtYJXux2i+zQB+pC5nmwQ@public.gmane.org \
--cc=hj-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=hl-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=huangtao-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=kever.yang-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
--cc=linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
--cc=max.schwarz-BGeptl67XyCzQB+pC5nmwQ@public.gmane.org \
--cc=olof-nZhT3qVonbNeoWH0uzbU5w@public.gmane.org \
--cc=xjq-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=yzq-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=zhengsq-TNX95d0MmH7DzftRWevZcw@public.gmane.org \
--cc=zyw-TNX95d0MmH7DzftRWevZcw@public.gmane.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).