Introduce an is_undervoltage parameter to _mmc_suspend() to apply a
short power-off sequence and optionally flush the cache. This refactoring
prepares for undervoltage support in a follow-up patch.
Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>
---
changes v3:
- add comments
- make sure _mmc_flush_cache is not executed in the undervoltage case
---
drivers/mmc/core/mmc.c | 30 +++++++++++++++++++++---------
1 file changed, 21 insertions(+), 9 deletions(-)
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 6a23be214543..9270bde445ad 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -2104,20 +2104,32 @@ static int _mmc_flush_cache(struct mmc_host *host)
return err;
}
-static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
+static int _mmc_suspend(struct mmc_host *host, bool is_suspend,
+ bool is_undervoltage)
{
+ unsigned int notify_type;
int err = 0;
- unsigned int notify_type = is_suspend ? EXT_CSD_POWER_OFF_SHORT :
- EXT_CSD_POWER_OFF_LONG;
+
+ /* In case of undervoltage, we don't have much time, so use short. */
+ if (is_undervoltage || is_suspend)
+ notify_type = EXT_CSD_POWER_OFF_SHORT;
+ else
+ notify_type = EXT_CSD_POWER_OFF_LONG;
mmc_claim_host(host);
if (mmc_card_suspended(host->card))
goto out;
- err = _mmc_flush_cache(host);
- if (err)
- goto out;
+ /*
+ * For the undervoltage case, we care more about device integrity.
+ * Avoid cache flush and notify the device to power off quickly.
+ */
+ if (!is_undervoltage) {
+ err = _mmc_flush_cache(host);
+ if (err)
+ goto out;
+ }
if (mmc_can_poweroff_notify(host->card) &&
((host->caps2 & MMC_CAP2_FULL_PWR_CYCLE) || !is_suspend ||
@@ -2144,7 +2156,7 @@ static int mmc_suspend(struct mmc_host *host)
{
int err;
- err = _mmc_suspend(host, true);
+ err = _mmc_suspend(host, true, false);
if (!err) {
pm_runtime_disable(&host->card->dev);
pm_runtime_set_suspended(&host->card->dev);
@@ -2191,7 +2203,7 @@ static int mmc_shutdown(struct mmc_host *host)
err = _mmc_resume(host);
if (!err)
- err = _mmc_suspend(host, false);
+ err = _mmc_suspend(host, false, false);
return err;
}
@@ -2215,7 +2227,7 @@ static int mmc_runtime_suspend(struct mmc_host *host)
if (!(host->caps & MMC_CAP_AGGRESSIVE_PM))
return 0;
- err = _mmc_suspend(host, true);
+ err = _mmc_suspend(host, true, false);
if (err)
pr_err("%s: error %d doing aggressive suspend\n",
mmc_hostname(host), err);
--
2.39.5
