Re: [PATCH v3 0/3] ARM: OMAP2+ McASP(3) support for DRA7xx family

[Paul Walmsley]

Hi Péter

On Fri, 30 Oct 2015, Peter Ujfalusi wrote:

> Changes since v2:
> - DTS patch added which is needed because of the clock handling changes
> 
> Felip Balbi reported that linux-next is broken right now since the DTS part of
> the earlier series has been applied, but we do not have the mcasp hwmod in the
> kernel:
> ...
> [    0.181029] platform 48468000.mcasp: Cannot lookup hwmod 'mcasp3'
> ...
> [    6.121072] davinci-mcasp 48468000.mcasp: _od_fail_runtime_resume: FIXME: missing hwmod/omap_dev info
> [    6.130790] ------------[ cut here ]------------
> [    6.135643] WARNING: CPU: 0 PID: 244 at drivers/bus/omap_l3_noc.c:147 l3_interrupt_handler+0x220/0x34c()
> [    6.145576] 44000000.ocp:L3 Custom Error: MASTER MPU TARGET L4_PER2_P3 (Read): Data Access in User mode during Functional access
> ...
> 
> This is the followup series for the hwmod changes needed to get audio working
> on DRA7xx family based boards.
> The DTS patches has been applied by Tony from the original series:
> http://www.spinics.net/lists/linux-omap/msg121473.html
> 
> I have addressed your comments in the hwmod data and did some research also
> regarding to the use of ahclkx as fclk in the original submission.
> It turned out that McASP _needs_ all clocks to be enabled (fclk, iclk and
> ahclkx/r) to be able to access registers. The original patch where we handled
> the ahclkx as fclk worked, because the fclk clock got enabled in the HW w/o
> any SW interaction.
> All in all, the McASP found in DRA7 needs all clocks to be enabled.
> To satisfy this I have introduced a new flag to hwmod, which means that the
> listed optional clocks need to be handled alongside with the fclk clock.

Thanks.  I'm happy with your series and appreciate the indepth 
investigation.  As you probably saw last week, we've hit the limit for 
v4.4-rc1:

http://marc.info/?l=linux-omap&m=144564929721826&w=2

This is why I haven't done anything with this series at this time.  
Unfortunately I don't have a DRA7xx board, so I can't do any testing.  
But if this series fixes a problem with DRA7xx in linux-next, we should 
definitely merge it.

Tony, if you want to take this now, you can either take it with my ack, or 
I can send a pull request.  Or, if you'd prefer to take it for v4.4-rc2, 
I can send a pull request after v4.4-rc1.


- Paul