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 for <linuxppc-dev@lists.ozlabs.org>; Thu, 27 Mar 2014 14:07:30 +1100 (EST)
Date: Thu, 27 Mar 2014 10:56:48 +0800
From: Nicolin Chen <Guangyu.Chen@freescale.com>
To: Xiubo Li-B47053 <Li.Xiubo@freescale.com>
Subject: Re: [PATCH] ASoC: fsl_sai: Add isr to deal with error flag
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On Thu, Mar 27, 2014 at 10:53:50AM +0800, Xiubo Li-B47053 wrote:
> > On Thu, Mar 27, 2014 at 10:13:48AM +0800, Xiubo Li-B47053 wrote:
> > > > +	regmap_read(sai->regmap, FSL_SAI_TCSR, &xcsr);
> > > > +	regmap_write(sai->regmap, FSL_SAI_TCSR, xcsr);
> > > > +
> > > > +	if (xcsr & FSL_SAI_CSR_WSF)
> > > > +		dev_dbg(dev, "isr: Start of Tx word detected\n");
> > > > +
> > > > +	if (xcsr & FSL_SAI_CSR_SEF)
> > > > +		dev_dbg(dev, "isr: Tx Frame sync error detected\n");
> > > > +
> > > > +	if (xcsr & FSL_SAI_CSR_FEF)
> > > > +		dev_dbg(dev, "isr: Transmit underrun detected\n");
> > > > +
> > >
> > > Actually, the above three isrs should to write a logic 1 to this field
> > > to clear this flag.
> > >
> > >
> > > > +	if (xcsr & FSL_SAI_CSR_FWF)
> > > > +		dev_dbg(dev, "isr: Enabled transmit FIFO is empty\n");
> > > > +
> > > > +	if (xcsr & FSL_SAI_CSR_FRF)
> > > > +		dev_dbg(dev, "isr: Transmit FIFO watermark has been reached\n");
> > > > +
> > >
> > > While are these ones really needed to clear manually ?
> > 
> > The reference manual doesn't mention about the requirement. So SAI should do
> > the self-clearance.
> 
> Yes, I do think we should let it do the self-clearance, and shouldn't interfere
> of them...

SAI is supposed to ignore the interference, isn't it?