[PATCHv2 1/8] ALSA: Add SAI SoC Digital Audio Interface driver.

[Li Xiubo]

> > > The udelay just doesn't make sense to what you are talking about.
> > >
> > > Does SAI really need 10us delay between two register-updating?
> > >
> >
> > No, this is not must be.
> 
> Then you should explain in your comments why you really put it here or
> just drop it if it's just a mistake.
> 

The udelay will be removed then.


> > > ISSUE 2: There are two cases listed in 'Synchronous mode'.
> > > 	 However, your driver doesn't take care of them.
> > > 	 The SAI's synchronous mode looks like more flexible
> > > 	 than SSI's. The driver needs to be more sophisticated
> > > 	 so that it can handle multiple cases when TX/RX clocks
> > > 	 are controlled by either TX or RX, and surely, the
> > > 	 asynchronous mode as well.
> > >
> >
> > Because in Vybrid the transmitter bit clock and frame sync are to be
> > used by both the transmitter and receiver, and only this case can be
> > used here, so now I only handle this case.
> 
> It's fairly okay if adding explicit comments to indicate that currently
> the driver only supports its Synchronous mode with clocks controlled by
> TX only.
> 

Just think, on other platforms maybe only the Rx's clock is available.
Thus I think there should be one DT property to control this, and then the SAI driver can be more flexible.

Or could you give me some more practical ideas ?

--
Best Regards,
Xiubo