mmc: core: Use mmc_flush_cache() during mmc suspend

Earlier we disabled the cache during suspend, which meant a flush was
internally at the eMMC performed as well.

To simplify code we can make use of the mmc_flush_cache(), during mmc
suspend, which makes the mmc_cache_ctrl() redundant so then we can
remove it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Chris Ball <chris@printf.net>

drivers/mmc/core/core.c

@@ -2582,44 +2582,6 @@ int mmc_flush_cache(struct mmc_card *card)
 }
 EXPORT_SYMBOL(mmc_flush_cache);
 
-/*
- * Turn the cache ON/OFF.
- * Turning the cache OFF shall trigger flushing of the data
- * to the non-volatile storage.
- * This function should be called with host claimed
- */
-int mmc_cache_ctrl(struct mmc_host *host, u8 enable)
-{
-	struct mmc_card *card = host->card;
-	unsigned int timeout;
-	int err = 0;
-
-	if (!(host->caps2 & MMC_CAP2_CACHE_CTRL) ||
-			mmc_card_is_removable(host))
-		return err;
-
-	if (card && mmc_card_mmc(card) &&
-			(card->ext_csd.cache_size > 0)) {
-		enable = !!enable;
-
-		if (card->ext_csd.cache_ctrl ^ enable) {
-			timeout = enable ? card->ext_csd.generic_cmd6_time : 0;
-			err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
-					EXT_CSD_CACHE_CTRL, enable, timeout);
-			if (err)
-				pr_err("%s: cache %s error %d\n",
-						mmc_hostname(card->host),
-						enable ? "on" : "off",
-						err);
-			else
-				card->ext_csd.cache_ctrl = enable;
-		}
-	}
-
-	return err;
-}
-EXPORT_SYMBOL(mmc_cache_ctrl);
-
 #ifdef CONFIG_PM
 
 /* Do the card removal on suspend if card is assumed removeable

drivers/mmc/core/mmc.c

@@ -1481,7 +1481,7 @@ static int _mmc_suspend(struct mmc_host *host, bool is_suspend)
 			goto out;
 	}
 
-	err = mmc_cache_ctrl(host, 0);
+	err = mmc_flush_cache(host->card);
 	if (err)
 		goto out;
 

include/linux/mmc/host.h

@@ -385,8 +385,6 @@ int mmc_power_restore_host(struct mmc_host *host);
 void mmc_detect_change(struct mmc_host *, unsigned long delay);
 void mmc_request_done(struct mmc_host *, struct mmc_request *);
 
-int mmc_cache_ctrl(struct mmc_host *, u8);
-
 static inline void mmc_signal_sdio_irq(struct mmc_host *host)
 {
 	host->ops->enable_sdio_irq(host, 0);