linux-kernel - Re: [PATCH v3 4/5] iio: imu: st_lsm6dsx: add support for accel/gyro unit of lsm9sd1

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <a2f6d5fe-04c6-f5d8-ad38-56b8fa033295@puri.sm>
Date:   Sun, 28 Jul 2019 08:04:51 +0200
From:   Martin Kepplinger <martin.kepplinger@...i.sm>
To:     Jonathan Cameron <jic23@...nel.org>
Cc:     lorenzo.bianconi83@...il.com, knaack.h@....de, lars@...afoo.de,
        pmeerw@...erw.net, linux-iio@...r.kernel.org,
        devicetree@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH v3 4/5] iio: imu: st_lsm6dsx: add support for accel/gyro
 unit of lsm9sd1

On 27.07.19 19:48, Jonathan Cameron wrote:
> On Thu, 25 Jul 2019 07:31:31 +0200
> Martin Kepplinger <martin.kepplinger@...i.sm> wrote:
> 
>> The LSM9DS1's accelerometer / gyroscope unit and it's magnetometer (separately
>> supported in iio/magnetometer/st_magn*) are located on a separate i2c addresses
>> on the bus.
>>
>> For the datasheet, see https://www.st.com/resource/en/datasheet/lsm9ds1.pdf
>>
>> Treat it just like the LSM6* devices and, despite it's name, hook it up
>> to the st_lsm6dsx driver, using it's basic functionality.
>>
>> Signed-off-by: Martin Kepplinger <martin.kepplinger@...i.sm>
> I'm a little confused on this hardware.
> 
> How does buffered output work if these are independently clocked?
> 
> I took a quick look at the datasheet, and 'suspect' the answer is that
> it runs at the gyro frequencies if both are enable. Is that right?
> 

Thanks for reviewing, Jonathan,

Correct. It says so in chapter 7.12. But that's a "problem" with all
these imu devices, not specific to this addition right?

Sidenote: I thought about renaming things to "lsm6ds0" here just because
of the name and because the registers are (almost) the same as for my
lsm9ds1. But I'm not a fan of blindly doing that without being able to
test. When the current patchset looks good to you, let's keep it that way.

                            martin