From: balbi@ti.com (Felipe Balbi)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3] i2c: omap: improve duty cycle on SCL
Date: Tue, 18 Aug 2015 09:43:47 -0500 [thread overview]
Message-ID: <20150818144347.GD9143@saruman.tx.rr.com> (raw)
In-Reply-To: <CAFqkuUbO1CZ8bu8g8O7SsLF-0nUV274GZ08=6J1sVS4Foy+_EA@mail.gmail.com>
HI,
On Mon, Aug 17, 2015 at 06:28:11PM -0700, Matt Reimer wrote:
> This doesn't seem to work for higher speeds, like 2.6 MHz. hssclh and
> hsscll end up going negative.
>
> My case is an OMAP3 trying to configure i2c1 at 2.6 MHz, on which it talks
> to TPS65950. I end up with the following values:
>
> SCLL 0x0000fd12 SCLH 0x0000fe13
>
> The end result is that the high-speed part gets configured way too slow and
> so the OMAP3 can't talk to the TPS65950.
hmm, indeed. Seems like anything above 1MHz would have an issue. I'll
see what can be done there.
--
balbi
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From: Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org>
To: Matt Reimer <mreimer-9nEMHBxvMEgxoycv7ERPSQ@public.gmane.org>
Cc: balbi-l0cyMroinI0@public.gmane.org,
Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>,
Alexander Sverdlin
<alexander.sverdlin-xNZwKgViW5gAvxtiuMwx3w@public.gmane.org>,
Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>,
Dave Gerlach <d-gerlach-l0cyMroinI0@public.gmane.org>,
Nishanth Menon <nm-l0cyMroinI0@public.gmane.org>,
linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Linux OMAP Mailing List
<linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
Linux ARM Kernel Mailing List
<linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>
Subject: Re: [PATCH v3] i2c: omap: improve duty cycle on SCL
Date: Tue, 18 Aug 2015 09:43:47 -0500 [thread overview]
Message-ID: <20150818144347.GD9143@saruman.tx.rr.com> (raw)
In-Reply-To: <CAFqkuUbO1CZ8bu8g8O7SsLF-0nUV274GZ08=6J1sVS4Foy+_EA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
[-- Attachment #1: Type: text/plain, Size: 599 bytes --]
HI,
On Mon, Aug 17, 2015 at 06:28:11PM -0700, Matt Reimer wrote:
> This doesn't seem to work for higher speeds, like 2.6 MHz. hssclh and
> hsscll end up going negative.
>
> My case is an OMAP3 trying to configure i2c1 at 2.6 MHz, on which it talks
> to TPS65950. I end up with the following values:
>
> SCLL 0x0000fd12 SCLH 0x0000fe13
>
> The end result is that the high-speed part gets configured way too slow and
> so the OMAP3 can't talk to the TPS65950.
hmm, indeed. Seems like anything above 1MHz would have an issue. I'll
see what can be done there.
--
balbi
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
next prev parent reply other threads:[~2015-08-18 14:43 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-17 19:31 [PATCH v3] i2c: omap: improve duty cycle on SCL Felipe Balbi
2015-06-17 19:31 ` Felipe Balbi
2015-06-18 8:09 ` Alexander Sverdlin
2015-06-18 8:09 ` Alexander Sverdlin
2015-06-18 17:25 ` Felipe Balbi
2015-06-18 17:25 ` Felipe Balbi
2015-07-09 19:42 ` Wolfram Sang
2015-07-09 19:42 ` Wolfram Sang
2015-07-10 17:27 ` Felipe Balbi
2015-07-10 17:27 ` Felipe Balbi
2015-08-13 14:36 ` Felipe Balbi
2015-08-13 14:36 ` Felipe Balbi
[not found] ` <CAFqkuUbO1CZ8bu8g8O7SsLF-0nUV274GZ08=6J1sVS4Foy+_EA@mail.gmail.com>
2015-08-18 14:43 ` Felipe Balbi [this message]
2015-08-18 14:43 ` Felipe Balbi
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