mmc: sdhci: fix interrupt storm from card detection

The issue was initially found by Eric Benard as below.

http://permalink.gmane.org/gmane.linux.ports.arm.kernel/108031

Not sure about other SDHCI based controller, but on Freescale eSDHC,
the SDHCI_INT_CARD_INSERT bits will be immediately set again when it
gets cleared, if a card is inserted. The driver need to mask the irq
to prevent interrupt storm which will freeze the system.  And the
SDHCI_INT_CARD_REMOVE gets the same situation.

The patch fixes the problem based on the initial idea from
Eric Benard.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Cc: Eric Benard <eric@eukrea.com>
Tested-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: Revert "mmc: sdhci: Fix SDHCI_QUIRK_TIMEOUT_USES_SDCLK"

This reverts commit 4b01681c7764, which introduced a new potential
divide by zero in the process of fixing one.  The subsequent commits
attempt to fix the issue properly.

Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: move timeout_clk calculation farther down

This moves the calculation below the assignment of mmc->f_max, which
we need for calculating timeout_clk in the next patch in this series.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: sdhci: use f_max instead of host->clock for timeouts

When timeout_clk is calculated the host->clock could be zero.
So, instead of host->clock the calculation now uses mmc->f_max.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: Add module.h to drivers/mmc users assuming implicit presence.

We are cleaning up the implicit presence of module.h; these guys are
some of the people who just assume it will be there.  Call it out
explitly for those that really need it.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
MMC: Cleaned drivers/mmc/core/core.c