From: Peter Rosin <peda@axentia.se>
To: Jonathan Cameron <jic23@kernel.org>,
Crestez Dan Leonard <leonard.crestez@intel.com>,
<linux-iio@vger.kernel.org>
Cc: <linux-kernel@vger.kernel.org>, Hartmut Knaack <knaack.h@gmx.de>,
Lars-Peter Clausen <lars@metafoo.de>,
Peter Meerwald-Stadler <pmeerw@pmeerw.net>,
Daniel Baluta <daniel.baluta@intel.com>,
<linux-i2c@vger.kernel.org>, Wolfram Sang <wsa@the-dreams.de>,
<devicetree@vger.kernel.org>, Rob Herring <robh+dt@kernel.org>,
Pawel Moll <pawel.moll@arm.com>,
Mark Rutland <mark.rutland@arm.com>,
Ian Campbell <ijc+devicetree@hellion.org.uk>,
Kumar Gala <galak@codeaurora.org>
Subject: Re: [PATCH] iio: inv_mpu6050: Add support for auxiliary I2C master
Date: Wed, 27 Apr 2016 10:39:17 +0200 [thread overview]
Message-ID: <6ab228db-9695-ac22-9c65-fd15c4837c45@axentia.se> (raw)
In-Reply-To: <a978ad85-8191-7506-8090-809f89d0b2e2@kernel.org>
Hi!
On 2016-04-23 23:32, Jonathan Cameron wrote:
> On 20/04/16 18:17, Crestez Dan Leonard wrote:
>> The MPU has an auxiliary I2C bus for connecting external
>> sensors. This bus has two operating modes:
>> * pass-through, which connects the primary and auxiliary busses
>> together. This is already supported via an i2c mux.
>> * I2C master mode, where the mpu60x0 acts as a master to any external
>> connected sensors. This is implemented by this patch.
>>
>> This I2C master mode also works when the MPU itself is connected via
>> SPI.
>>
>> I2C master supports up to 5 slaves. Slaves 0-3 have a common operating
>> mode while slave 4 is different. This patch implements an i2c adapter
>> using slave 4 because it has a cleaner interface and it has an
>> interrupt that signals when data from slave to master arrived.
>>
>> Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
> This one needs acks from:
>
> Device tree maintainer (odd binding ;)
> Peter Rosin (odd binding interacting with the mux support)
> Wolfram (it has a whole i2c master driver in here).
>
> (just thought I'd list these for the avoidance of doubt).
I spot some overlap with the questions in "[RFC] i2c: device-tree:
Handling child nodes which are not i2c devices"
http://marc.info/?l=linux-i2c&m=146073452819116&w=2
And I think I agree with Stephen Warren that an intermediate placeholder
node would make sense. I.e.
mpu6050@68 {
compatible = "...";
reg = <0x68>;
...
i2c-aux-mux {
i2c@0 {
#address-cells = <1>;
#size-cells = <0>;
reg = <0>;
foo@44 {
compatible = "bar";
reg = <0x44>;
...
}
}
}
}
Or
mpu6050@68 {
compatible = "...";
reg = <0x68>;
...
i2c-aux-master {
#address-cells = <1>;
#size-cells = <0>;
gazonk@44 {
compatible = "baz";
reg = <0x44>;
...
}
}
}
depending on if you want an aux-mux or an aux-master.
But I don't know if that intermediate i2c-aux-mux node causes any
problems?
Cheers,
Peter
next prev parent reply other threads:[~2016-04-27 8:39 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-20 17:17 [PATCH] iio: inv_mpu6050: Add support for auxiliary I2C master Crestez Dan Leonard
2016-04-20 18:17 ` kbuild test robot
2016-04-21 10:02 ` Crestez Dan Leonard
2016-04-23 21:32 ` Jonathan Cameron
2016-04-27 8:39 ` Peter Rosin [this message]
2016-04-28 10:39 ` Crestez Dan Leonard
2016-04-29 9:29 ` Peter Rosin
2016-04-29 10:09 ` Peter Rosin
2016-04-20 20:31 Peter Rosin
2016-04-21 12:01 ` Crestez Dan Leonard
2016-04-21 13:56 Peter Rosin
2016-04-22 10:15 ` Crestez Dan Leonard
2016-04-22 11:01 Peter Rosin
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=6ab228db-9695-ac22-9c65-fd15c4837c45@axentia.se \
--to=peda@axentia.se \
--cc=daniel.baluta@intel.com \
--cc=devicetree@vger.kernel.org \
--cc=galak@codeaurora.org \
--cc=ijc+devicetree@hellion.org.uk \
--cc=jic23@kernel.org \
--cc=knaack.h@gmx.de \
--cc=lars@metafoo.de \
--cc=leonard.crestez@intel.com \
--cc=linux-i2c@vger.kernel.org \
--cc=linux-iio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=pawel.moll@arm.com \
--cc=pmeerw@pmeerw.net \
--cc=robh+dt@kernel.org \
--cc=wsa@the-dreams.de \
/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).