Commit 52af318c authored May 25, 2018 by Evan Green Committed by Ulf Hansson May 29, 2018

mmc: Allow non-sleeping GPIO cd



This change uses the appropriate _cansleep or non-sleeping API for
reading GPIO card detect state. This allows users with GPIOs that
never sleep to avoid a warning when certain quirks are present.

The sdhci controller has an SDHCI_QUIRK_NO_CARD_NO_RESET, which
indicates that a controller will not reset properly if no card is
inserted. With this quirk enabled, mmc_get_cd_gpio is called in
several places with a spinlock held and interrupts disabled.
gpiod_get_raw_value_cansleep is not happy with this situation,
and throws out a warning.

For boards that a) use controllers that have this quirk, and b) wire
card detect up to a GPIO that doesn't sleep, this is a spurious warning.
This change silences that warning, at the cost of pushing this problem
down to users that have sleeping GPIOs and controllers with this quirk.

Signed-off-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

parent fb8617e1

drivers/mmc/core/slot-gpio.c

+11 −4

Original line number	Diff line number	Diff line
		@@ -79,15 +79,22 @@ EXPORT_SYMBOL(mmc_gpio_get_ro);
		int mmc_gpio_get_cd(struct mmc_host *host)
		{
		struct mmc_gpio *ctx = host->slot.handler_priv;
		int cansleep;

		if (!ctx \|\| !ctx->cd_gpio)
		return -ENOSYS;

		if (ctx->override_cd_active_level)
		return !gpiod_get_raw_value_cansleep(ctx->cd_gpio) ^
		!!(host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
		cansleep = gpiod_cansleep(ctx->cd_gpio);
		if (ctx->override_cd_active_level) {
		int value = cansleep ?
		gpiod_get_raw_value_cansleep(ctx->cd_gpio) :
		gpiod_get_raw_value(ctx->cd_gpio);
		return !value ^ !!(host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
		}

		return gpiod_get_value_cansleep(ctx->cd_gpio);
		return cansleep ?
		gpiod_get_value_cansleep(ctx->cd_gpio) :
		gpiod_get_value(ctx->cd_gpio);
		}
		EXPORT_SYMBOL(mmc_gpio_get_cd);

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