From: Troy Kisky <troy.kisky-Q5RJGjKts06CY9SHAMCTRUEOCMrvLtNR@public.gmane.org>
To: Jon Povey <Jon.Povey-Ean/AyPsLtfkYMGBc/C6ZA@public.gmane.org>
Cc: Sudhakar Rajashekhara <sudhakar.raj-l0cyMroinI0@public.gmane.org>,
"linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
<linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
"davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org"
<davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/@public.gmane.org>,
Dirk Behme <dirk.behme-gM/Ye1E23mwN+BqQ9rBEUg@public.gmane.org>
Subject: Re: [PATCH v3] i2c: davinci: Fix race when setting up for TX
Date: Mon, 20 Sep 2010 14:14:49 -0700 [thread overview]
Message-ID: <4C97CEC9.8060602@boundarydevices.com> (raw)
In-Reply-To: <70E876B0EA86DD4BAF101844BC814DFE093ED5F50E-lPJtnb2sqtq44ywRPIzf9A@public.gmane.org>
>> On 9/17/2010 6:09 AM, Sudhakar Rajashekhara wrote:
>>> I remember I had some issues on OMAP-L138 with this fix, that's when
>>> I reverted to configuring ICMDR before writing to DXR (Please see
>>> here: https://patchwork.kernel.org/patch/75262/). I checked the BIOS
>>> I2C driver code for OMAP-L138 and there also we are configuring MDR
>>> before accessing DXR.
>
> Ah :/
>
>>
>> and resetting the i2c upon a NAK interrupt (after the stop)
>> to clear the bad fifo data?
>
> I can't really comment on how valid that would be and can't easily test it.
>
> However preloading DXR does save one interrupt on transmit so the whole operation is faster and more efficient.
>
> Maybe v1 of my patch, with locking, is the best option?
>
> --
> Jon Povey
How about writing MDR twice? Once where Sudakar wants it, without the start bit.
And then where you want it with the start bit?
Troy
next prev parent reply other threads:[~2010-09-20 21:14 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-17 2:46 [PATCH v2] i2c: davinci: Fix race when setting up for TX Jon Povey
[not found] ` <1284691607-9697-1-git-send-email-jon.povey-Ean/AyPsLtfkYMGBc/C6ZA@public.gmane.org>
2010-09-17 3:02 ` [PATCH v3] " Jon Povey
[not found] ` <1284692531-10100-1-git-send-email-jon.povey-Ean/AyPsLtfkYMGBc/C6ZA@public.gmane.org>
2010-09-17 13:09 ` Sudhakar Rajashekhara
[not found] ` <001201cb5669$a0200940$e0601bc0$@raj@ti.com>
[not found] ` <001201cb5669$a0200940$e0601bc0$@raj-l0cyMroinI0@public.gmane.org>
2010-09-17 19:15 ` Troy Kisky
[not found] ` <4C93BE5B.6090701-Q5RJGjKts06CY9SHAMCTRUEOCMrvLtNR@public.gmane.org>
2010-09-20 4:40 ` Jon Povey
[not found] ` <70E876B0EA86DD4BAF101844BC814DFE093ED5F50E-lPJtnb2sqtq44ywRPIzf9A@public.gmane.org>
2010-09-20 21:14 ` Troy Kisky [this message]
[not found] ` <4C97CEC9.8060602-Q5RJGjKts06CY9SHAMCTRUEOCMrvLtNR@public.gmane.org>
2010-09-21 4:13 ` [PATCH v4] " Jon Povey
[not found] ` <026901cb597f$86fa9980$94efcc80$@raj@ti.com>
[not found] ` <026901cb597f$86fa9980$94efcc80$@raj-l0cyMroinI0@public.gmane.org>
2010-09-21 19:17 ` Troy Kisky
[not found] ` <4C9904E6.7070608-Q5RJGjKts06CY9SHAMCTRUEOCMrvLtNR@public.gmane.org>
2010-09-22 0:09 ` Ben Dooks
[not found] ` <20100922000916.GH7494-SMNkleLxa3Z6Wcw2j4pizdi2O/JbrIOy@public.gmane.org>
2010-09-22 10:50 ` Sudhakar Rajashekhara
2010-09-30 13:10 ` Kevin Hilman
[not found] ` <87wrq3l6m0.fsf-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>
2010-10-07 8:39 ` Jon Povey
[not found] ` <70E876B0EA86DD4BAF101844BC814DFE093EE3EA57-lPJtnb2sqtq44ywRPIzf9A@public.gmane.org>
2010-10-07 17:01 ` Kevin Hilman
[not found] ` <87wrpu9bsu.fsf-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>
2010-10-07 17:20 ` Kevin Hilman
[not found] ` <87hbgxapig.fsf-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>
2010-10-12 4:48 ` Jon Povey
2010-09-23 14:27 ` Kevin Hilman
[not found] ` <87d3s47cx1.fsf-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>
2010-09-23 20:27 ` Troy Kisky
[not found] ` <1285042408-13200-1-git-send-email-jon.povey-Ean/AyPsLtfkYMGBc/C6ZA@public.gmane.org>
2010-09-21 11:24 ` Sudhakar Rajashekhara
2010-09-24 4:42 ` Sudhakar Rajashekhara
[not found] ` <022501cb5ba2$d801d760$88058620$@raj@ti.com>
[not found] ` <022501cb5ba2$d801d760$88058620$@raj-l0cyMroinI0@public.gmane.org>
2010-09-24 14:37 ` Kevin Hilman
[not found] ` <87sk0zky28.fsf-1D3HCaltpLuhEniVeURVKkEOCMrvLtNR@public.gmane.org>
2010-09-24 16:37 ` Ben Dooks
[not found] ` <20100924163754.GH27885-SMNkleLxa3Z6Wcw2j4pizdi2O/JbrIOy@public.gmane.org>
2010-09-27 14:16 ` Kevin Hilman
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