Re: [PATCH 1/2] mmc: renesas_sdhi: skip SCC error check when retuning

From: "Niklas Söderlund" <niklas.soderlund@ragnatech.se>
To: Wolfram Sang <wsa@the-dreams.de>
Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	linux-mmc@vger.kernel.org, linux-renesas-soc@vger.kernel.org,
	Masaharu Hayakawa <masaharu.hayakawa.ry@renesas.com>
Subject: Re: [PATCH 1/2] mmc: renesas_sdhi: skip SCC error check when retuning
Date: Wed, 25 Jul 2018 15:36:43 +0200	[thread overview]
Message-ID: <20180725133643.GE14991@bigcity.dyn.berto.se> (raw)
In-Reply-To: <20180725122106.jzv6v3j2wrtqrt6t@ninjato>

Hi Wolfram,

On 2018-07-25 14:21:07 +0200, Wolfram Sang wrote:
> Hi Niklas,
> 
> > * Changes since v3
> > - Add check for 4TAP for HS400.
> 
> Is it the same in the BSP or where does this info come from?

It comes from the BSP but I had to modify it to fit with the upstream 
implementation of 4 vs 8 taps. The original code from BSP:

        if (!(host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) &&
            !(host->mmc->ios.timing == MMC_TIMING_MMC_HS200) &&
            !(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 &&
              !host->hs400_use_4tap))
                return false;
> 
> 
> > +	if (!(host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) &&
> > +	    !(host->mmc->ios.timing == MMC_TIMING_MMC_HS200) &&
> > +	    !(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 &&
> > +	      !(host->pdata->flags & TMIO_MMC_HAVE_4TAP_HS400)))
> 
> This becomes very hard to read. We need to simplify it.

I agree but I could not find a neat way of doing it. How about?

    bool use_4tap = host->pdata->flags & TMIO_MMC_HAVE_4TAP_HS400;

    if (!(host->mmc->ios.timing == MMC_TIMING_UHS_SDR104) &&
	!(host->mmc->ios.timing == MMC_TIMING_MMC_HS200) &&
	!(host->mmc->ios.timing == MMC_TIMING_MMC_HS400 && !use_4tap))
	   return false;

> 
> And can you bounce me your debugging mail from today again? I seem to
> have lost it :(

Bounced.

> 
> Thanks,
> 
>    Wolfram

-- 
Regards,
Niklas Sï¿½derlund