Re: [PATCH] sdhci: disable MMC_CAP_NEEDS_POLL in nonremovable case

[Matt Fleming <matt@console-pimps.org>]

On Fri, Aug 27, 2010 at 07:55:44PM +0800, Gao, Yunpeng wrote:
> >-----Original Message-----
> >From: linux-mmc-owner@vger.kernel.org
> >[mailto:linux-mmc-owner@vger.kernel.org] On Behalf Of Kyungmin Park
> >Sent: Friday, August 27, 2010 3:15 PM
> >To: Matt Fleming
> >Cc: Jaehoon Chung; linux-mmc@vger.kernel.org; Marek Szyprowski; Andrew Morton;
> >Ben Dooks
> >Subject: Re: [PATCH] sdhci: disable MMC_CAP_NEEDS_POLL in nonremovable case
> >
> >On Fri, Aug 27, 2010 at 4:09 PM, Matt Fleming <matt@console-pimps.org> wrote:
> >> On Fri, Aug 27, 2010 at 03:34:54PM +0900, Jaehoon Chung wrote:
> >>> If controller use SDHCI_QUIRK_BROKEN_CARD_DETECTION quirk,
> >>> controller need always polling detect
> >>>
> >>> In this case, always generated interrupt.Because controller checked card
> >status.
> >>> I think that is not efficiently.
> >>>
> >>> But if card is nonremovable, we need not always polling.
> >>> So i added the check-point which is nonremovable or not
> >>>
> >>>  Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
> >>> ---
> >>>  drivers/mmc/host/sdhci.c |    5 +++--
> >>>  1 files changed, 3 insertions(+), 2 deletions(-)
> >>>
> >>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> >>> index 401527d..4bc5d3c 100644
> >>> --- a/drivers/mmc/host/sdhci.c
> >>> +++ b/drivers/mmc/host/sdhci.c
> >>> @@ -1826,8 +1826,9 @@ int sdhci_add_host(struct sdhci_host *host)
> >>>       if (caps & SDHCI_CAN_DO_HISPD)
> >>>               mmc->caps |= MMC_CAP_SD_HIGHSPEED;
> >>>
> >>> -     if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)
> >>> -             mmc->caps |= MMC_CAP_NEEDS_POLL;
> >>> +     if ((host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION) &&
> >>> +             !(host->mmc->caps & MMC_CAP_NONREMOVABLE))
> >>> +                     mmc->caps |= MMC_CAP_NEEDS_POLL;
> 
> Since module parameter 'mmc_assume_removable' (defined in core.c) also
> controls the nonremovable attribute of the mmc/eMMC device, will it be
> better to also check value of 'mmc_assume_removable' here? Thanks.

Yeah, I think that check is also needed. I've got a couple of patches
that I'll reply to this thread with. There should really be a helper
function for determining when a card is either physially non-removable
(eMMC) or logically non-removable (mmc_assume_removable == 0).