mmc: Don't force card to active state when entering suspend/shutdown

By adding a card state that records if it is suspended or resumed, we
can accept asyncronus suspend/resume requests for the mmc and sd
bus_ops.

MMC_CAP_AGGRESSIVE_PM, will at request inactivity through the runtime
bus_ops callbacks, execute a suspend of the the card. In the state were
this has been done, we can receive a suspend request for the mmc bus,
which for sd and mmc forced the card to active state by a
pm_runtime_get_sync. In other words, the card was resumed and then
immediately suspended again, completely unnecessary.

Since the suspend/resume bus_ops callbacks for sd and mmc are now
capable of handling asynchronous requests, we no longer need to force
the card to active state before executing suspend. Evidently preventing
the above sequence for MMC_CAP_AGGRESSIVE_PM.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

2 files changed, 51 insertions, 15 deletions

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 0d060227cfc..84d8694cf36 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1478,6 +1478,9 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
 
 	mmc_claim_host(host);
 
+	if (mmc_card_suspended(host->card))
+		goto out;
+
 	if (mmc_card_doing_bkops(host->card)) {
 		err = mmc_stop_bkops(host->card);
 		if (err)
@@ -1497,8 +1500,10 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
 		err = mmc_deselect_cards(host);
 	host->card->state &= ~(MMC_STATE_HIGHSPEED | MMC_STATE_HIGHSPEED_200);
 
-	if (!err)
+	if (!err) {
 		mmc_power_off(host);
+		mmc_card_set_suspended(host->card);
+	}
 out:
 	mmc_release_host(host);
 	return err;
@@ -1513,14 +1518,6 @@ static int mmc_suspend(struct mmc_host *host)
 }
 
 /*
- * Shutdown callback
- */
-static int mmc_shutdown(struct mmc_host *host)
-{
-	return _mmc_suspend(host, false);
-}
-
-/*
  * Resume callback from host.
  *
  * This function tries to determine if the same card is still present
@@ -1528,19 +1525,45 @@ static int mmc_shutdown(struct mmc_host *host)
  */
 static int mmc_resume(struct mmc_host *host)
 {
-	int err;
+	int err = 0;
 
 	BUG_ON(!host);
 	BUG_ON(!host->card);
 
 	mmc_claim_host(host);
+
+	if (!mmc_card_suspended(host->card))
+		goto out;
+
 	mmc_power_up(host, host->card->ocr);
 	err = mmc_init_card(host, host->card->ocr, host->card);
-	mmc_release_host(host);
+	mmc_card_clr_suspended(host->card);
 
+out:
+	mmc_release_host(host);
 	return err;
 }
 
+/*
+ * Shutdown callback
+ */
+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 (mmc_can_poweroff_notify(host->card) &&
+		!(host->caps2 & MMC_CAP2_FULL_PWR_CYCLE))
+		err = mmc_resume(host);
+
+	if (!err)
+		err = _mmc_suspend(host, false);
+
+	return err;
+}
 
 /*
  * Callback for runtime_suspend.
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 6ef84d0ca17..685796560f8 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -1078,13 +1078,20 @@ static int mmc_sd_suspend(struct mmc_host *host)
 	BUG_ON(!host->card);
 
 	mmc_claim_host(host);
+
+	if (mmc_card_suspended(host->card))
+		goto out;
+
 	if (!mmc_host_is_spi(host))
 		err = mmc_deselect_cards(host);
 	host->card->state &= ~MMC_STATE_HIGHSPEED;
-	if (!err)
+	if (!err) {
 		mmc_power_off(host);
-	mmc_release_host(host);
+		mmc_card_set_suspended(host->card);
+	}
 
+out:
+	mmc_release_host(host);
 	return err;
 }
 
@@ -1096,16 +1103,22 @@ static int mmc_sd_suspend(struct mmc_host *host)
  */
 static int mmc_sd_resume(struct mmc_host *host)
 {
-	int err;
+	int err = 0;
 
 	BUG_ON(!host);
 	BUG_ON(!host->card);
 
 	mmc_claim_host(host);
+
+	if (!mmc_card_suspended(host->card))
+		goto out;
+
 	mmc_power_up(host, host->card->ocr);
 	err = mmc_sd_init_card(host, host->card->ocr, host->card);
-	mmc_release_host(host);
+	mmc_card_clr_suspended(host->card);
 
+out:
+	mmc_release_host(host);
 	return err;
 }