mmc: core: Add cache control for eMMC4.5 device

[pandora-kernel.git] / drivers / mmc / core / core.c

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 772de2c..235bb6a 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2158,6 +2158,65 @@ int mmc_card_can_sleep(struct mmc_host *host)
 }
 EXPORT_SYMBOL(mmc_card_can_sleep);
 
+/*
+ * Flush the cache to the non-volatile storage.
+ */
+int mmc_flush_cache(struct mmc_card *card)
+{
+       struct mmc_host *host = card->host;
+       int err = 0;
+
+       if (!(host->caps2 & MMC_CAP2_CACHE_CTRL))
+               return err;
+
+       if (mmc_card_mmc(card) &&
+                       (card->ext_csd.cache_size > 0) &&
+                       (card->ext_csd.cache_ctrl & 1)) {
+               err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                               EXT_CSD_FLUSH_CACHE, 1, 0);
+               if (err)
+                       pr_err("%s: cache flush error %d\n",
+                                       mmc_hostname(card->host), err);
+       }
+
+       return err;
+}
+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.
+ */
+int mmc_cache_ctrl(struct mmc_host *host, u8 enable)
+{
+       struct mmc_card *card = host->card;
+       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)
+                       err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+                                       EXT_CSD_CACHE_CTRL, enable, 0);
+               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
 
 /**
@@ -2172,6 +2231,9 @@ int mmc_suspend_host(struct mmc_host *host)
                cancel_delayed_work(&host->disable);
        cancel_delayed_work(&host->detect);
        mmc_flush_scheduled_work();
+       err = mmc_cache_ctrl(host, 0);
+       if (err)
+               goto out;
 
        mmc_bus_get(host);
        if (host->bus_ops && !host->bus_dead) {
@@ -2197,6 +2259,7 @@ int mmc_suspend_host(struct mmc_host *host)
        if (!err && !mmc_card_keep_power(host))
                mmc_power_off(host);
 
+out:
        return err;
 }