[PATCH v3 0/4] Add PWM clock support for bcm2835

Martin Sperl martin at sperl.org
Fri Jan 8 10:24:21 PST 2016

> On 08.01.2016, at 19:19, Remi Pommarel <repk at triplefau.lt> wrote:
> Hi Martin,
> On Fri, Jan 08, 2016 at 10:21:47AM +0100, Martin Sperl wrote:
>> Is there any driver that is currently making use of this (in or out of tree)?
> There is drivers/pwm/pwm-bcm2835.c that uses this. But seeing your other
> messages I guess you managed to get something working.
>> I am working on getting the i2s driver back into working order
>> with the clock-framework, so I wonder how I could use that.
>> As I2S is either using PPL or OSC as parent I was thinking of using this
>> patchset of yours as a basis to allow this selection to work properly.
>> Any ideas about using MASH - I2S makes use of this as well and I would
>> assume that PWM could also make use of this feature…
> If I'm not wrong here, we do a 1-stage MASH filtering, for what I tried
> it gives me pretty good rate approximations.

It does not look as if mashing is really used - you just use the fractional
clock (MASH = 0).

In the meantime I am about to send out a patchset so that bcm2835-i2s
is using the clock framework. This is based on your patches.

Still MASH support would probably be nice...


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