[PATCH] mmc: change mmc_gpio_get_cd to call non-sleep gpio

From: Christian Daudt
Date: Thu Aug 08 2013 - 16:47:54 EST


Given that mmc_gpio_get_cd can be called in softirq
context (by sdhci_tasklet_card -> sdhci_card_event ->
sdhci_do_get_cd -> mmc_gpio_get_cd ), it is necessary
for it to use gpio_get_value instead of
gpio_get_value_cansleep
Note that at present sdhci_card_event gets called both
from mmc_gpio_cd_irqt and sdhci_tasklet_card, and from
both it gets called immediately while the actual cd
processing is debounced to 200ms later. I think that
the better solution might be to move the sdhci_card_event
callback into mmc_rescan and remove it from its 2
present locations. That way the cd related callbacks
are aligned with the actual cd detection code. I can
submit a follow-up patch with these mods if that sounds
like a better way to solve this.

Signed-off-by: Christian Daudt <csd@xxxxxxxxxxxx>

diff --git a/drivers/mmc/core/slot-gpio.c b/drivers/mmc/core/slot-gpio.c
index 3242351..897b298 100644
--- a/drivers/mmc/core/slot-gpio.c
+++ b/drivers/mmc/core/slot-gpio.c
@@ -87,7 +87,7 @@ int mmc_gpio_get_cd(struct mmc_host *host)
if (!ctx || !gpio_is_valid(ctx->cd_gpio))
return -ENOSYS;

- return !gpio_get_value_cansleep(ctx->cd_gpio) ^
+ return !gpio_get_value(ctx->cd_gpio) ^
!!(host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
}
EXPORT_SYMBOL(mmc_gpio_get_cd);
--
1.7.10.4


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