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mmc: core: Further avoid re-storing power to the eMMC before a shutdown

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To manage a graceful power-off of the eMMC card during platform shutdown,
the prioritized option is to use the poweroff-notification command, if the
eMMC card supports it.

During a suspend request we may decide to fall back to use the sleep
command, instead of the poweroff-notification, unless the mmc host supports
a complete power-cycle of the eMMC. For this reason, we may need to restore
power and re-initialize the card, if it remains suspended when a shutdown
request is received.

However, the current condition to restore power and re-initialize the card
doesn't take into account MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND properly. This
may lead to doing a re-initialization when it really isn't needed, as the
eMMC may already have been powered-off using the poweroff-notification
command. Let's fix the condition to avoid this.

Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20250407152759.25160-3-ulf.hansson@linaro.org
This commit is contained in:
Ulf Hansson
2025-04-07 17:27:52 +02:00
parent 3953e7e8c1
commit fa34c940e8
1 changed files with 17 additions and 5 deletions
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22
drivers/mmc/core/mmc.c
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@@ -2014,6 +2014,18 @@ static bool mmc_can_poweroff_notify(const struct mmc_card *card)
(card->ext_csd.power_off_notification == EXT_CSD_POWER_ON);
}
static bool mmc_host_can_poweroff_notify(const struct mmc_host *host,
bool is_suspend)
{
if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE)
return true;
if (host->caps2 & MMC_CAP2_FULL_PWR_CYCLE_IN_SUSPEND && is_suspend)
return true;
return !is_suspend;
}
static int mmc_poweroff_notify(struct mmc_card *card, unsigned int notify_type)
{
unsigned int timeout = card->ext_csd.generic_cmd6_time;
@@ -2124,8 +2136,7 @@ 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_IN_SUSPEND)))
mmc_host_can_poweroff_notify(host, is_suspend))
err = mmc_poweroff_notify(host->card, notify_type);
else if (mmc_can_sleep(host->card))
err = mmc_sleep(host);
@@ -2187,11 +2198,12 @@ static int mmc_shutdown(struct mmc_host *host)
int err = 0;
/*
* In a specific case for poweroff notify, we need to resume the card
* before we can shutdown it properly.
* If the card remains suspended at this point and it was done by using
* the sleep-cmd (CMD5), we may need to re-initialize it first, to allow
* us to send the preferred poweroff-notification cmd at shutdown.
*/
if (mmc_can_poweroff_notify(host->card) &&
!(host->caps2 & MMC_CAP2_FULL_PWR_CYCLE))
!mmc_host_can_poweroff_notify(host, true))
err = _mmc_resume(host);
if (!err)