[U-Boot] [v2, 1/5] mmc: fsl_esdhc: don't set XFERTYP_RSPTYP_48_BUSY for CMD with busy response

[Y.B. Lu]

> -----Original Message-----
> From: Jaehoon Chung [mailto:jh80.chung at samsung.com]
> Sent: Monday, September 19, 2016 8:07 AM
> To: Y.B. Lu; u-boot at lists.denx.de
> Cc: york sun
> Subject: Re: [v2, 1/5] mmc: fsl_esdhc: don't set XFERTYP_RSPTYP_48_BUSY
> for CMD with busy response
> 
> Hi Yangbo,
> 
> On 08/02/2016 06:20 PM, Yangbo Lu wrote:
> > For CMD with busy response, the eSDHC driver would poll DAT0 until CMD
> > completion rather than polling IRQSTAT. So, don't set
> > XFERTYP_RSPTYP_48_BUSY to avoid interrupts (DTOE or TC) in IRQSTAT.
> 
> Sorry for late.. I missed your patchset.
> 
> >
> > Signed-off-by: Yangbo Lu <yangbo.lu at nxp.com>
> > ---
> > Changes for v2:
> > 	- None
> > ---
> >  drivers/mmc/fsl_esdhc.c | 12 ++++++++++--
> >  1 file changed, 10 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index
> > a865c7b..b23845d 100644
> > --- a/drivers/mmc/fsl_esdhc.c
> > +++ b/drivers/mmc/fsl_esdhc.c
> > @@ -136,8 +136,16 @@ static uint esdhc_xfertyp(struct mmc_cmd *cmd,
> struct mmc_data *data)
> >  		xfertyp |= XFERTYP_CICEN;
> >  	if (cmd->resp_type & MMC_RSP_136)
> >  		xfertyp |= XFERTYP_RSPTYP_136;
> > -	else if (cmd->resp_type & MMC_RSP_BUSY)
> > -		xfertyp |= XFERTYP_RSPTYP_48_BUSY;
> > +	/*
> > +	 * For CMD with busy response, the eSDHC driver would poll DAT0
> > +	 * until CMD completion rather than polling IRQSTAT. So, don't
> > +	 * set XFERTYP_RSPTYP_48_BUSY to avoid interrupts (DTOE or TC)
> > +	 * in IRQSTAT.
> > +	 *
> > +	 * Remove:
> > +	 * else if (cmd->resp_type & MMC_RSP_BUSY)
> > +	 *      xfertyp |= XFERTYP_RSPTYP_48_BUSY;
> > +	 */
> 
> I don't have the board that is using the fsl_esdhc driver.
> I wonder that it doesn't need to set XFERTYP_RSPTYP_48_BUSY in future.
> If so be, is it possible to remove this comments?
> 
> Why add this comment?

[Lu Yangbo-B47093] I added this comment to explain why there isn't XFERTYP_RSPTYP_48_BUSY setting in esdhc_xfertyp().
Because usually the xfertyp should be XFERTYP_RSPTYP_48_BUSY for cmd with busy response.

Although we don't need to set XFERTYP_RSPTYP_48_BUSY in the future, I'd like to keep an explain comment here if possible :)

> 
> Best Regards,
> Jaehoon Chung
> 
> >  	else if (cmd->resp_type & MMC_RSP_PRESENT)
> >  		xfertyp |= XFERTYP_RSPTYP_48;
> >
> >