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>

drivers/mmc/card/block.c

@@ -2448,7 +2448,6 @@ static int _mmc_blk_suspend(struct mmc_card *card)
 	struct mmc_blk_data *md = mmc_get_drvdata(card);
 
 	if (md) {
-		pm_runtime_get_sync(&card->dev);
 		mmc_queue_suspend(&md->queue);
 		list_for_each_entry(part_md, &md->part, part) {
 			mmc_queue_suspend(&part_md->queue);
@@ -2483,7 +2482,6 @@ static int mmc_blk_resume(struct mmc_card *card)
 		list_for_each_entry(part_md, &md->part, part) {
 			mmc_queue_resume(&part_md->queue);
 		}
-		pm_runtime_put(&card->dev);
 	}
 	return 0;
 }

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;
@@ -1512,14 +1517,6 @@ static int mmc_suspend(struct mmc_host *host)
 	return _mmc_suspend(host, true);
 }
 
-/*
- * Shutdown callback
- */
-static int mmc_shutdown(struct mmc_host *host)
-{
-	return _mmc_suspend(host, false);
-}
-
 /*
  * Resume callback from host.
  *
@@ -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.

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;
 }
 

include/linux/mmc/card.h

@@ -258,6 +258,7 @@ struct mmc_card {
 #define MMC_CARD_REMOVED	(1<<7)		/* card has been removed */
 #define MMC_STATE_HIGHSPEED_200	(1<<8)		/* card is in HS200 mode */
 #define MMC_STATE_DOING_BKOPS	(1<<10)		/* card is doing BKOPS */
+#define MMC_STATE_SUSPENDED	(1<<11)		/* card is suspended */
 	unsigned int		quirks; 	/* card quirks */
 #define MMC_QUIRK_LENIENT_FN0	(1<<0)		/* allow SDIO FN0 writes outside of the VS CCCR range */
 #define MMC_QUIRK_BLKSZ_FOR_BYTE_MODE (1<<1)	/* use func->cur_blksize */
@@ -424,6 +425,7 @@ static inline void __maybe_unused remove_quirk(struct mmc_card *card, int data)
 #define mmc_card_ext_capacity(c) ((c)->state & MMC_CARD_SDXC)
 #define mmc_card_removed(c)	((c) && ((c)->state & MMC_CARD_REMOVED))
 #define mmc_card_doing_bkops(c)	((c)->state & MMC_STATE_DOING_BKOPS)
+#define mmc_card_suspended(c)	((c)->state & MMC_STATE_SUSPENDED)
 
 #define mmc_card_set_present(c)	((c)->state |= MMC_STATE_PRESENT)
 #define mmc_card_set_readonly(c) ((c)->state |= MMC_STATE_READONLY)
@@ -436,6 +438,8 @@ static inline void __maybe_unused remove_quirk(struct mmc_card *card, int data)
 #define mmc_card_set_removed(c) ((c)->state |= MMC_CARD_REMOVED)
 #define mmc_card_set_doing_bkops(c)	((c)->state |= MMC_STATE_DOING_BKOPS)
 #define mmc_card_clr_doing_bkops(c)	((c)->state &= ~MMC_STATE_DOING_BKOPS)
+#define mmc_card_set_suspended(c) ((c)->state |= MMC_STATE_SUSPENDED)
+#define mmc_card_clr_suspended(c) ((c)->state &= ~MMC_STATE_SUSPENDED)
 
 /*
  * Quirk add/remove for MMC products.