From: grygorii.strashko@ti•com (Grygorii Strashko)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH v2 5/5] i2c: davinci: use ICPFUNC to toggle I2C as gpio for bus recovery
Date: Wed, 26 Nov 2014 19:05:31 +0200 [thread overview]
Message-ID: <5476085B.40009@ti.com> (raw)
In-Reply-To: <20141126160407.GN4431@pengutronix.de>
On 11/26/2014 06:04 PM, Uwe Kleine-K?nig wrote:
> On Wed, Nov 26, 2014 at 03:59:53PM +0200, Grygorii Strashko wrote:
>> Having a board where the I2C bus locks up occasionally made it clear
>> that the bus recovery in the i2c-davinci driver will only work on
>> some boards, because on regular boards, this will only toggle GPIO
>> lines that aren't muxed to the actual pins.
>>
>> The I2C controller on SoCs like da850 (and da830), Keystone 2 has the
>> built-in capability to bit-bang its lines by using the ICPFUNC registers
>> of the i2c controller.
>> Implement the suggested procedure by toggling SCL and checking SDA using
>> the ICPFUNC registers of the I2C controller when present. Allow platforms
>> to indicate the presence of the ICPFUNC registers with a has_pfunc platform
>> data flag and add optional DT property "ti,has-pfunc" to indicate
>> the same in DT.
> On what does it depend if this pfunc stuff works or not? Only the SoC,
> or also on some board specific properties?
SoC / set of SoCs. Also, similar feature is supported by OMAP and AM335x/AM437x SoCs
using I2C_SYSTEST register.
> Given the former using the
> compatible string to detect its availability would be better. (In this
> case also sorry, didn't consider this case when requesting the property
> in the last round.)
>
> The patch looks ok.
regards,
-grygorii
next prev parent reply other threads:[~2014-11-26 17:05 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-26 13:59 [PATCH v2 0/5] i2c: davinci improvements and fixes Grygorii Strashko
2014-11-26 13:59 ` [PATCH v2 1/5] i2c: i2c-davinci: switch to use platform_get_irq Grygorii Strashko
2014-11-26 15:54 ` Uwe Kleine-König
2014-11-26 16:28 ` Grygorii Strashko
2014-11-26 13:59 ` [PATCH v2 2/5] i2c: davinci: query STP always when NACK is received Grygorii Strashko
2014-11-26 15:57 ` Uwe Kleine-König
2014-11-26 16:31 ` Grygorii Strashko
2014-11-26 17:15 ` Uwe Kleine-König
2014-11-26 13:59 ` [PATCH v2 3/5] i2c: recovery: change input parameter to i2c_adapter for prepare/unprepare_recovery Grygorii Strashko
2014-11-26 13:59 ` [PATCH v2 4/5] i2c: davinci: use bus recovery infrastructure Grygorii Strashko
2014-11-26 15:59 ` Uwe Kleine-König
2014-11-26 13:59 ` [PATCH v2 5/5] i2c: davinci: use ICPFUNC to toggle I2C as gpio for bus recovery Grygorii Strashko
2014-11-26 16:04 ` Uwe Kleine-König
2014-11-26 17:05 ` Grygorii Strashko [this message]
2015-07-07 13:37 ` Jan Lübbe
2015-07-07 13:43 ` Wolfram Sang
2015-07-07 13:48 ` Uwe Kleine-König
2015-07-07 14:13 ` Wolfram Sang
2015-07-07 14:53 ` Grygorii Strashko
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=5476085B.40009@ti.com \
--to=grygorii.strashko@ti$(echo .)com \
--cc=linux-arm-kernel@lists$(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