Re: [PATCH V2] ASoC: fsl_ssi: refine ipg clock usage in this module

On Fri, Sep 12, 2014 at 08:17:06AM +0200, Markus Pargmann wrote:

Hi,

On Fri, Sep 12, 2014 at 10:01:12AM +0800, Shengjiu Wang wrote:

quoted

On Thu, Sep 11, 2014 at 03:57:37PM -0700, Nicolin Chen wrote:

quoted

On Thu, Sep 11, 2014 at 01:38:29PM +0800, Shengjiu Wang wrote:

quoted

Move the ipg clock enable and disable operation to startup and shutdown,
that is only enable ipg clock when ssi is working. Keep clock is disabled
when ssi is in idle.
otherwise, _fsl_ssi_set_dai_fmt function need to be called in probe,
so add ipg clock control for it.

It seems to be no objection so far against my last suggestion to
use regmap's mmio_clk() for named ipg clk only. So you may still
consider about that.

I think mmio_clk() can be put to another patch. and this patch only for clk_enable()
and clk_disable() operation.

I would also prefer Nicolin's suggestion using regmap's mmio clk. I
think it may be better to not add this particular patch at all and just
go with the mmio_clk patch. It should be easy enough to just add the
clock names to the devicetrees. That way we can avoid all those clock
enable/disable function calls.

I considered if use Nicolin's suggestion, I still need ot add those
enable/disable function calls, because I want to remove the enable/disable
function call in fsl_ssi_imx_probe, then I need to add enable/disable 
function call in _fsl_ssi_set_dai_fmt(), which is called in fsl_ssi_probe().
_fsl_ssi_set_dai_fmt() need to access the registers.

quoted

quoted

Anyway, I'd like to do thing in parallel. So I just simply tested
it on my side and its works fine, it may still need to be tested
by others though.

Nicolina

Hi Markus

could you please review it, and share your comments?

I think the clock enabling for AC97 is missing in your patch.

I add clock enable in fsl_ssi_startup(), I think it is enough for AC97, does it?

wang shengjiu

Best regards,

Markus

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