Commit a31b0c6c authored by Kristina Martsenko's avatar Kristina Martsenko Committed by Ulf Hansson
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mmc: core: fix card detection regression 



Since commit 89168b48 ("mmc: core: restore detect line inversion
semantics"), the SD card on i.MX28 (and possibly other) devices isn't
detected and booting stops at:

[    4.120617] Waiting for root device /dev/mmcblk0p3...

This is caused by the MMC_CAP2_CD_ACTIVE_HIGH flag being set incorrectly
when the host controller doesn't use a GPIO for card detection (but
instead uses a dedicated pin). In this case mmc_gpiod_request_cd() will
return before assigning to the gpio_invert variable, leaving the
variable uninitialized. The variable then gets used to set the flag.
This patch fixes the issue by making sure gpio_invert is set to false
when a GPIO isn't used. After this patch, i.MX28 boots fine.

The MMC_CAP2_RO_ACTIVE_HIGH (write protect) flag is also set incorrectly
for the exact same reason (it uses the same uninitialized variable), so
this patch fixes that too.

Fixes: 89168b48 ("mmc: core: restore detect line inversion semantics")
Reported-by: default avatarStefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: default avatarKristina Martšenko <kristina.martsenko@gmail.com>
Tested-by: default avatarFabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 0df1f248

drivers/mmc/core/host.c

+8 −13
Original line number Diff line number Diff line
@@ -311,7 +311,8 @@ int mmc_of_parse(struct mmc_host *host) 
	struct device_node *np;

	u32 bus_width;

	int len, ret;

	bool cap_invert, gpio_invert;

	bool cd_cap_invert, cd_gpio_invert = false;

	bool ro_cap_invert, ro_gpio_invert = false;



	if (!host->parent || !host->parent->of_node)

		return 0;
@@ -359,16 +360,13 @@ int mmc_of_parse(struct mmc_host *host) 
	if (of_find_property(np, "non-removable", &len)) {

		host->caps |= MMC_CAP_NONREMOVABLE;

	} else {

		if (of_property_read_bool(np, "cd-inverted"))

			cap_invert = true;

		else

			cap_invert = false;

		cd_cap_invert = of_property_read_bool(np, "cd-inverted");



		if (of_find_property(np, "broken-cd", &len))

			host->caps |= MMC_CAP_NEEDS_POLL;



		ret = mmc_gpiod_request_cd(host, "cd", 0, true,

					   0, &gpio_invert);

					   0, &cd_gpio_invert);

		if (ret) {

			if (ret == -EPROBE_DEFER)

				return ret;
@@ -391,17 +389,14 @@ int mmc_of_parse(struct mmc_host *host) 
		 * both inverted, the end result is that the CD line is

		 * not inverted.

		 */

		if (cap_invert ^ gpio_invert)

		if (cd_cap_invert ^ cd_gpio_invert)

			host->caps2 |= MMC_CAP2_CD_ACTIVE_HIGH;

	}



	/* Parse Write Protection */

	if (of_property_read_bool(np, "wp-inverted"))

		cap_invert = true;

	else

		cap_invert = false;

	ro_cap_invert = of_property_read_bool(np, "wp-inverted");



	ret = mmc_gpiod_request_ro(host, "wp", 0, false, 0, &gpio_invert);

	ret = mmc_gpiod_request_ro(host, "wp", 0, false, 0, &ro_gpio_invert);

	if (ret) {

		if (ret == -EPROBE_DEFER)

			goto out;
@@ -414,7 +409,7 @@ int mmc_of_parse(struct mmc_host *host) 
		dev_info(host->parent, "Got WP GPIO\n");



	/* See the comment on CD inversion above */

	if (cap_invert ^ gpio_invert)

	if (ro_cap_invert ^ ro_gpio_invert)

		host->caps2 |= MMC_CAP2_RO_ACTIVE_HIGH;



	if (of_find_property(np, "cap-sd-highspeed", &len))

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