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From: Ohad Ben-Cohen <ohad@wizery.com>
To: linux-mmc@vger.kernel.org
Cc: Chris Ball <cjb@laptop.org>, Ohad Ben-Cohen <ohad@wizery.com>
Subject: [PATCH 2/2] mmc: quirks: wl1271 is MMC_QUIRK_DISABLE_CD
Date: Tue,  5 Apr 2011 18:02:26 +0300	[thread overview]
Message-ID: <1302015746-8414-2-git-send-email-ohad@wizery.com> (raw)
In-Reply-To: <1302015746-8414-1-git-send-email-ohad@wizery.com>

The wl12xx device supports disconnecting the pull-up resistor on
CD/DAT[3] (pin 1) of the card.

Tell SDIO core to disconnect that resistor during card init,
since we don't need it at that point (and anyway all
hosts shall provide pull-up resistors on all data lines DAT[3:0]
as described in section 6 of the SD physical specification).

As a result, this may save some power, but it's also generally healthy
since it prevents both ends from pulling up that pin, which
results in undesirable asymmetric physical bus.

Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
---
 drivers/mmc/core/quirks.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/drivers/mmc/core/quirks.c b/drivers/mmc/core/quirks.c
index 1957398..a4c42ed 100644
--- a/drivers/mmc/core/quirks.c
+++ b/drivers/mmc/core/quirks.c
@@ -66,6 +66,8 @@ static const struct mmc_fixup mmc_fixup_methods[] = {
 		remove_quirk, MMC_QUIRK_BROKEN_CLK_GATING },
 	{ SDIO_VENDOR_ID_TI, SDIO_DEVICE_ID_TI_WL1271,
 		add_quirk, MMC_QUIRK_NONSTD_FUNC_IF },
+	{ SDIO_VENDOR_ID_TI, SDIO_DEVICE_ID_TI_WL1271,
+		add_quirk, MMC_QUIRK_DISABLE_CD },
 	{ 0 }
 };
 
-- 
1.7.1


  reply	other threads:[~2011-04-05 15:03 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-04-05 15:02 [PATCH 1/2] mmc: add MMC_QUIRK_DISABLE_CD Ohad Ben-Cohen
2011-04-05 15:02 ` Ohad Ben-Cohen [this message]
2011-04-05 15:26   ` [PATCH 2/2] mmc: quirks: wl1271 is MMC_QUIRK_DISABLE_CD Chris Ball
2011-04-05 15:26 ` [PATCH 1/2] mmc: add MMC_QUIRK_DISABLE_CD Chris Ball

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