mmc: core: Add MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND

The commit 5a36d6bc ("mmc: core: Add DT-bindings for
MMC_CAP2_FULL_PWR_CYCLE") added the "full-pwr-cycle" property which
is possible to perform a full power cycle of the card at any time.

However, some environment (like r8a77951-salvator-xs) is possible
to perform a full power cycle of the card in suspend via firmware
(PSCI on arm-trusted-firmware). So, in worst case, since we are
not doing a graceful shutdown of the eMMC device (just cut VCCQ
while the eMMC is "sleeping") in suspend, it could lead to internal
data corruptions. So, add MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND
to do a graceful shutdown which issues Power Off notification
before entering system suspend.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1594123122-13156-3-git-send-email-yoshihiro.shimoda.uh@renesas.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/host.c

@@ -277,6 +277,8 @@ int mmc_of_parse(struct mmc_host *host)
 		host->caps |= MMC_CAP_SDIO_IRQ;
 	if (device_property_read_bool(dev, "full-pwr-cycle"))
 		host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE;
+	if (device_property_read_bool(dev, "full-pwr-cycle-in-suspend"))
+		host->caps2 |= MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND;
 	if (device_property_read_bool(dev, "keep-power-in-suspend"))
 		host->pm_caps |= MMC_PM_KEEP_POWER;
 	if (device_property_read_bool(dev, "wakeup-source") ||

drivers/mmc/core/mmc.c

@@ -2038,7 +2038,8 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
 		goto out;
 
 	if (mmc_can_poweroff_notify(host->card) &&
-		((host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) || !is_suspend))
+	    ((host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) || !is_suspend ||
+	     (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND)))
 		err = mmc_poweroff_notify(host->card, notify_type);
 	else if (mmc_can_sleep(host->card))
 		err = mmc_sleep(host);

include/linux/mmc/host.h

@@ -352,6 +352,7 @@ struct mmc_host {
 
 #define MMC_CAP2_BOOTPART_NOACC	(1 << 0)	/* Boot partition no access */
 #define MMC_CAP2_FULL_PWR_CYCLE	(1 << 2)	/* Can do full power cycle */
+#define MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND (1 << 3) /* Can do full power cycle in suspend */
 #define MMC_CAP2_HS200_1_8V_SDR	(1 << 5)        /* can support */
 #define MMC_CAP2_HS200_1_2V_SDR	(1 << 6)        /* can support */
 #define MMC_CAP2_HS200		(MMC_CAP2_HS200_1_8V_SDR | \