Commit bec9d4e5 authored Sep 17, 2012 by Guennadi Liakhovetski Committed by Chris Ball Sep 19, 2012

mmc: sdhci: Test cd-gpio instead of SDHCI presence when probing



Previously to this patch, an SDHCI platform that uses a GPIO for
card detection instead of the internal SDHCI_CARD_PRESENT bit on
the presence register would fail to detect a new card.

Some drivers worked around this in various ways: esdhc-imx defines
an IO accessor to fake the presence bit being true, s3c turns on
polling (which stops the SDHCI driver from checking the bit) after
a card's inserted.  But none of this should be necessary; the real
fix is to check whether we're using a GPIO and avoid relying on
the presence bit if so, as this patch implements.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>

parent 5413da81

drivers/mmc/host/sdhci.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -28,6 +28,7 @@
		#include <linux/mmc/mmc.h>
		#include <linux/mmc/host.h>
		#include <linux/mmc/card.h>
		#include <linux/mmc/slot-gpio.h>

		#include "sdhci.h"

		@@ -1293,6 +1294,13 @@ static void sdhci_request(struct mmc_host mmc, struct mmc_request mrq)
		present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
		SDHCI_CARD_PRESENT;

		/* If we're using a cd-gpio, testing the presence bit might fail. */
		if (!present) {
		int ret = mmc_gpio_get_cd(host->mmc);
		if (ret > 0)
		present = true;
		}

		if (!present \|\| host->flags & SDHCI_DEVICE_DEAD) {
		host->mrq->cmd->error = -ENOMEDIUM;
		tasklet_schedule(&host->finish_tasklet);

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