mmc: fixes for eMMC v4.5 discard operation

commit 7194efb8f063ee3aa0cb50d9002348887e68ec10 upstream.

eMMC v4.5 discard operation is significantly different from the
existing trim operation because it is not guaranteed to work with
the new sanitize operation.  Consequently mmc_can_trim() is
separated from mmc_can_discard().

Also the new discard operation does not result in the sectors being
set to all-zeros, so discard_zeroes_data must not be set.

In addition, the new discard has the same timeout as trim, but from
v4.5 trim is defined to use the hc timeout.  The timeout calculation
is adjusted accordingly.

Fixes apply to linux 3.2 on.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jaehoon Chung <jh80.chung@samsung.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/mmc/card/queue.c b/drivers/mmc/card/queue.c
index 2517547b4366a9bbdc6eea69ce1f1dc35ef09f08..996f8e36e23d8aa8bbf7c333fd6d6d56b8ec79ad 100644 (file)
--- a/drivers/mmc/card/queue.c
+++ b/drivers/mmc/card/queue.c
@@ -139,7 +139,7 @@ static void mmc_queue_setup_discard(struct request_queue *q,
 
        queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, q);
        q->limits.max_discard_sectors = max_discard;
-       if (card->erased_byte == 0)
+       if (card->erased_byte == 0 && !mmc_can_discard(card))
                q->limits.discard_zeroes_data = 1;
        q->limits.discard_granularity = card->pref_erase << 9;
        /* granularity must not be greater than max. discard */

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 132378b89d76a0072fe31b7f436975525d04e353..fc2c54be79a8c681017a2c4f127cd77694ad9fca 100644 (file)
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1557,7 +1557,10 @@ static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,
 {
        unsigned int erase_timeout;
 
-       if (card->ext_csd.erase_group_def & 1) {
+       if (arg == MMC_DISCARD_ARG ||
+           (arg == MMC_TRIM_ARG && card->ext_csd.rev >= 6)) {
+               erase_timeout = card->ext_csd.trim_timeout;
+       } else if (card->ext_csd.erase_group_def & 1) {
                /* High Capacity Erase Group Size uses HC timeouts */
                if (arg == MMC_TRIM_ARG)
                        erase_timeout = card->ext_csd.trim_timeout;
@@ -1829,8 +1832,6 @@ int mmc_can_trim(struct mmc_card *card)
 {
        if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_GB_CL_EN)
                return 1;
-       if (mmc_can_discard(card))
-               return 1;
        return 0;
 }
 EXPORT_SYMBOL(mmc_can_trim);