[Letux-kernel] Request for tasks

[H. Nikolaus Schaller]

Hi Andrey,

> Am 07.06.2016 um 00:51 schrieb Andrey Utkin <andrey_utkin at fastmail.com>:
> 
> On Sun, May 29, 2016 at 01:32:34PM +0200, H. Nikolaus Schaller wrote:
>>> BTW There is a ready kernal driver for BMG160:
>>> https://github.com/BoschSensortec/Linux_Kernel_Drivers/tree/master/drivers/input/misc/BMG160
>> 
>> Ah, yes.
> 
> I am somewhat confused by what you've written earlier:
> 
>> We have these sensor chips:
>> * BMC160
>> * BMG150
>> * or BNO055
>> * BME280
> 
> But now I see that there's no datasheet available for BMG150 and BMC160
> - only BMG160 and BMC150.
> 
> BUT, there's drivers/iio/{magnetometer,accel}/bmc150* in upstream kernel.
> 
> But for BMG, there's just drivers/iio/gyro/bmg160* , so no "150".
> 
> Could you please confirm exact chip names?

Sorry for the confusion. Was my fault. I mixed them up in my original mail.
We have indeed BMC150 and BMG160.

> 
>> BTW: the BME280 has two sensors in one and the BMP085 should be very similar.
>> AFAIR the BMC150 also has two chips inside (BMM150 and some BMA220). For the latter there is also a driver.
> 
> BME280 support has been developed lately by one guy from Intel (BTW
> seems all Bosch drivers in mainline kernel are maintained by Intel), it
> is pending some likely-trivial rebasing and resubmission to kernel
> upstream:
> http://www.spinics.net/lists/linux-iio/msg23988.html

Oh that is a very interesting finding! Thank you.

> I could contact him to ask about his plans for new submission, and if
> there's any more code we could benefit from :)

Yes, please. Any piece of information we can get could help. And any
push to get it into mainline helps as well.

So we simply should wait for the submission to LKML. Then I can include
it in our "forward ports" branch so that we have it - until it trickles into
linus/master. Then we can remove it as our private addition.

One thing we still have to add/fix will be the DT node. Maybe you could
look into the bindings defined by the Intel guy and check what we have
to change (if anything). Current Pyra DT is:

http://git.goldelico.com/?p=gta04-kernel.git;a=blob;f=arch/arm/boot/dts/pyra-mainboard.dtsi;h=a7c5dd8ae0eff79610a88de282a39233db0656cf;hb=refs/heads/letux-4.7-rc1#l438

It looks quite preliminary/partially wrong to me (even if I have written it :).

Hope to fix the boards this week so that you can get hardware to test on asap.

> 
> BTW Intel has some IoT project which includes drivers for many of
> mentioned chips, but not in form of Linux kernel modules:
> https://github.com/intel-iot-devkit/upm/pull/423

Well, IoT is usually done with small microcontrollers and rarely with Linux...

> 
> 
> So, if we pretend that we've got BME280 driver, and those bm[cg]1[56]0
> which are already in upstream kernel, which drivers are still lacking?

So your findings show that it is less lacking than I had thought.
So we will soon have drivers for the standard sensor set.

There is the BNO055 which ED has not choosen for cost reasons.
But I am working with my contact with Bosch and he tries to get
special conditions. Looks like they want to support us and use Pyra
as a reference design :) He is also looking for a technical contact.

Thanks and BR,
Nikolaus