diff options
| author | Kyungmin Park <kyungmin.park@samsung.com> | 2011-10-18 09:34:04 +0900 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2011-10-26 16:32:27 -0400 |
| commit | b3bf915308ca2b50f3beec6cc824083870f0f4b5 (patch) | |
| tree | 955978242b333e1388358b4b50b5f8f4a5abca04 /drivers | |
| parent | d9ddd62943ee07a75d0428ffcf52f1a747a28c39 (diff) | |
| download | lwn-b3bf915308ca2b50f3beec6cc824083870f0f4b5.tar.gz lwn-b3bf915308ca2b50f3beec6cc824083870f0f4b5.zip | |
mmc: core: new discard feature support at eMMC v4.5
MMC v4.5 supports the DISCARD feature (CMD38). It's different from
trim and there's no check bit. Currently it's only supported at v4.5.
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/card/block.c | 4 | ||||
| -rw-r--r-- | drivers/mmc/core/core.c | 14 | ||||
| -rw-r--r-- | drivers/mmc/core/mmc.c | 4 |
3 files changed, 21 insertions, 1 deletions
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c index e85816e1634a..370472797fff 100644 --- a/drivers/mmc/card/block.c +++ b/drivers/mmc/card/block.c @@ -756,7 +756,9 @@ static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req) from = blk_rq_pos(req); nr = blk_rq_sectors(req); - if (mmc_can_trim(card)) + if (mmc_can_discard(card)) + arg = MMC_DISCARD_ARG; + else if (mmc_can_trim(card)) arg = MMC_TRIM_ARG; else arg = MMC_ERASE_ARG; diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index d9836e5a4e59..772de2cdfd1d 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -1709,10 +1709,24 @@ 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); +int mmc_can_discard(struct mmc_card *card) +{ + /* + * As there's no way to detect the discard support bit at v4.5 + * use the s/w feature support filed. + */ + if (card->ext_csd.feature_support & MMC_DISCARD_FEATURE) + return 1; + return 0; +} +EXPORT_SYMBOL(mmc_can_discard); + int mmc_can_sanitize(struct mmc_card *card) { if (card->ext_csd.sec_feature_support & EXT_CSD_SEC_SANITIZE) diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index f8ea9387d75c..54088768776c 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -452,6 +452,10 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) card->ext_csd.rst_n_function = ext_csd[EXT_CSD_RST_N_FUNCTION]; } + /* eMMC v4.5 or later */ + if (card->ext_csd.rev >= 6) + card->ext_csd.feature_support |= MMC_DISCARD_FEATURE; + card->ext_csd.raw_erased_mem_count = ext_csd[EXT_CSD_ERASED_MEM_CONT]; if (ext_csd[EXT_CSD_ERASED_MEM_CONT]) card->erased_byte = 0xFF; |