>From 6a8fc91e198de80774c3c40246d0eee83366effc Mon Sep 17 00:00:00 2001
From: Chuanxiao Dong <[email protected]>
Date: Mon, 22 Nov 2010 16:31:12 +0800
Subject: [PATCH 1/4] mmc: Enabled background operations feature if eMMC card supports
Background operations is a new feature defined in eMMC4.41 standard.
Since this feature is opertional for eMMC card, so driver only enable
for those eMMC card which supports this feature
Signed-off-by: Chuanxiao Dong <[email protected]>
---
drivers/mmc/core/mmc.c | 26 ++++++++++++++++++++++++++
include/linux/mmc/card.h | 2 ++
include/linux/mmc/mmc.h | 3 +++
3 files changed, 31 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 77f93c3..471ed82 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -310,6 +310,14 @@ static int mmc_read_ext_csd(struct mmc_card *card)
ext_csd[EXT_CSD_SEC_FEATURE_SUPPORT];
card->ext_csd.trim_timeout = 300 *
ext_csd[EXT_CSD_TRIM_MULT];
+
+ /* detect whether the eMMC card support BKOPS */
+ if (ext_csd[EXT_CSD_BKOPS_SUPPORT] & 0x1) {
+ card->ext_csd.bkops = 1;
+ card->ext_csd.bkops_en =
+ ext_csd[EXT_CSD_BKOPS_EN];
+ }
+
}
if (ext_csd[EXT_CSD_ERASED_MEM_CONT])
@@ -484,6 +492,24 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
}
/*
+ * enable BKOPS if eMMC card supports.
+ */
+ if (card->ext_csd.bkops) {
+ if (!card->ext_csd.bkops_en) {
+ err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+ EXT_CSD_BKOPS_EN, 1);
+ if (err && err != -EBADMSG)
+ goto free_card;
+
+ if (err) {
+ card->ext_csd.bkops_en = 0;
+ err = 0;
+ } else
+ card->ext_csd.bkops_en = 1;
+ }
+ }
+
+ /*
* Activate high speed (if supported)
*/
if ((card->ext_csd.hs_max_dtr != 0) &&
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 8ce0827..9b755cb 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -54,6 +54,8 @@ struct mmc_ext_csd {
unsigned int sec_trim_mult; /* Secure trim multiplier */
unsigned int sec_erase_mult; /* Secure erase multiplier */
unsigned int trim_timeout; /* In milliseconds */
+ unsigned int bkops:1; /* background support bit */
+ unsigned int bkops_en:1; /* background enable bit */
};
struct sd_scr {
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 956fbd8..14f7813 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -251,6 +251,8 @@ struct _mmc_csd {
* EXT_CSD fields
*/
+#define EXT_CSD_BKOPS_EN 163 /* R/W */
+#define EXT_CSD_BKOPS_START 164 /* W */
#define EXT_CSD_ERASE_GROUP_DEF 175 /* R/W */
#define EXT_CSD_ERASED_MEM_CONT 181 /* RO */
#define EXT_CSD_BUS_WIDTH 183 /* R/W */
@@ -266,6 +268,7 @@ struct _mmc_csd {
#define EXT_CSD_SEC_ERASE_MULT 230 /* RO */
#define EXT_CSD_SEC_FEATURE_SUPPORT 231 /* RO */
#define EXT_CSD_TRIM_MULT 232 /* RO */
+#define EXT_CSD_BKOPS_SUPPORT 502 /* RO */
/*
* EXT_CSD field definitions
--
1.6.6.1