On Wed, Sep 10, 2014 at 08:21:18AM +0200, Markus Pargmann wrote:
> On Tue, Sep 09, 2014 at 11:38:05AM -0700, Nicolin Chen wrote:
> > On Tue, Sep 09, 2014 at 05:18:07PM +0800, Shengjiu Wang wrote:
> > > @@ -1321,7 +1333,11 @@ static int fsl_ssi_probe(struct platform_device
> > > *pdev)
> > > return -ENOMEM;
> > > }
> > >
> > > - ssi_private->regs = devm_regmap_init_mmio(&pdev->dev, iomem,
> > > + if (ssi_private->soc->imx)
> > > + ssi_private->regs = devm_regmap_init_mmio_clk(&pdev->dev,
> > > + "ipg", iomem, &fsl_ssi_regconfig);
> > > + else
> > > + ssi_private->regs = devm_regmap_init_mmio(&pdev->dev, iomem,
> >
> > As Markus mentioned, the key point here is to be compatible with those
> > non-clock-name platforms.
> >
> > I think it would be safer to keep the current code while adding an extra
> > clk_disable_unprepare() at the end of probe() as a common routine. And
> > meantime, make sure to have the call for imx only because it seems that
> > the other platforms do not depend on the clock. //a bit guessing here :)
> >
> > Then we can get a patch like:
> > open() {
> > + clk_prepare_enable();
> > ....
> > }
> >
> > close() {
> > ....
> > + clk_disable_unprepare()
> > }
> >
> > probe() {
> > clk_get();
> > clk_prepare_enable();
> > ....
> > if (xxx)
> > - goto err_xx;
> > + return ret;
> > ....
> > + clk_disable_unprepare();
> > return 0;
> > -err_xx:
> > - clk_disable_unprepare()
> > }
> >
> > remove() {
> > ....
> > - clk_disable_unprepare()
> > }
>
> If I remember correctly, there may be AC97 communication with the codec
> before any substream is created. That's why we enable the SSI unit right
> at the beginning for AC97 in fsl_ssi_setup_reg_vals(). So we need to
> check for AC97 before disabling clocks.
Thank you for the input. That's the exact part I couldn't be sure.
And I agree that adding a check for AC97 will be safer while this
may keeps itself removable if being unnecessary.
Thanks
Nicolin
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