[PATCH] mmc: core: add MMC_QUIRK_BROKEN_WRITE_ZEROES for ESMT eMMC

[Mayur Kumar]

ESMT eMMC (SM0000) supports normal TRIM discard, but fails when TRIM
is used to offload WRITE_ZEROES operations.

Add a new card quirk, MMC_QUIRK_BROKEN_WRITE_ZEROES, to prevent setting
max_write_zeroes_sectors during queue setup when this quirk is present.
Apply this fixup to ESMT eMMC devices (CID_MANFID_ESM_MMC 0xEC,
CID 'SM0000').

Signed-off-by: Mayur Kumar <kmayur809@xxxxxxxxx>
---
 drivers/mmc/core/card.h   | 1 +
 drivers/mmc/core/queue.c  | 3 ++-
 drivers/mmc/core/quirks.h | 6 ++++++
 include/linux/mmc/card.h  | 1 +
 4 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/core/card.h b/drivers/mmc/core/card.h
index a7c364d0030..144a8f5e7d2 100644
--- a/drivers/mmc/core/card.h
+++ b/drivers/mmc/core/card.h
@@ -94,6 +94,7 @@ struct mmc_fixup {
 #define CID_MANFID_KINGSTON     0x70
 #define CID_MANFID_HYNIX	0x90
 #define CID_MANFID_KINGSTON_SD	0x9F
+#define CID_MANFID_ESMT_MMC	0xEC
 #define CID_MANFID_NUMONYX	0xFE
 
 #define END_FIXUP { NULL }
diff --git a/drivers/mmc/core/queue.c b/drivers/mmc/core/queue.c
index 5d187e063da..3ee640056a5 100644
--- a/drivers/mmc/core/queue.c
+++ b/drivers/mmc/core/queue.c
@@ -191,7 +191,8 @@ static void mmc_queue_setup_discard(struct mmc_card *card,
 			lim->max_secure_erase_sectors = max_discard;
 	}
 
-	if (mmc_card_can_trim(card) && card->erased_byte == 0)
+	if (mmc_card_can_trim(card) && card->erased_byte == 0 &&
+	    !(card->quirks & MMC_QUIRK_BROKEN_WRITE_ZEROS))
 		lim->max_write_zeroes_sectors = max_discard;
 
 	/* granularity must not be greater than max. discard */
diff --git a/drivers/mmc/core/quirks.h b/drivers/mmc/core/quirks.h
index ae3ece89d0a..91758fd7fc2 100644
--- a/drivers/mmc/core/quirks.h
+++ b/drivers/mmc/core/quirks.h
@@ -91,6 +91,12 @@ static const struct mmc_fixup __maybe_unused mmc_blk_fixups[] = {
 	MMC_FIXUP("MMC32G", CID_MANFID_TOSHIBA, CID_OEMID_ANY, add_quirk_mmc,
 		  MMC_QUIRK_BLK_NO_CMD23),
 
+	/* SM0000 supports normal TRIM discard but fails when TRIM is
+	 * used to offload WRITE_ZEROES, so we disable it.
+	 */
+	MMC_FIXUP("SM0000", CID_MANFID_ESMT_MMC, 0x0100, add_quirk_mmc,
+		  MMC_QUIRK_BROKEN_WRITE_ZEROES),
+
 	/*
 	 * Some SD cards lockup while using CMD23 multiblock transfers.
 	 */
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 9dc4750296a..938a4296b55 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -331,6 +331,7 @@ struct mmc_card {
 #define MMC_QUIRK_NO_UHS_DDR50_TUNING	(1<<18) /* Disable DDR50 tuning */
 #define MMC_QUIRK_BROKEN_MDT    (1<<19) /* Wrong manufacturing year */
 #define MMC_QUIRK_FIXED_SECURE_ERASE_TRIM_TIME	(1<<20) /* Secure erase/trim time is fixed regardless of size */
+#define MMC_QUIRK_BROKEN_WRITE_ZEROES	(1<<21)	/* Broken write zeroes via trim */
 
 	bool			written_flag;	/* Indicates eMMC has been written since power on */
 	bool			reenable_cmdq;	/* Re-enable Command Queue */
-- 
2.34.1