[PATCH V6 RESEND 1/2] mmc: core: Add power off notify feature(eMMC 4.5)

Girish K S
2011-09-16T13:39:36Z

This patch adds the support for power off notify feature
available in eMMC 4.5 devices.
If the the host has support for this feature, then the
mmc core will notify it to the device by setting the
POWER_OFF_NOTIFICATION byte in the extended csd register
with a value 1(POWER_ON).
This patch should be applied after Seungwon Jeon's
patch for cmd6 timeout.

Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
---
drivers/mmc/core/mmc.c | 19 +++++++++++++++++--
include/linux/mmc/card.h | 1 +
include/linux/mmc/host.h | 1 +
include/linux/mmc/mmc.h | 7 +++++++
4 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 68eb368..2f06b37 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -410,10 +410,12 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd)
else
card->erased_byte = 0x0;

- if (card->ext_csd.rev >= 6)
+ if (card->ext_csd.rev >= 6) {
card->ext_csd.generic_cmd6_time = 10 *
ext_csd[EXT_CSD_GENERIC_CMD6_TIME];
-
+ card->ext_csd.power_off_longtime = 10 *
+ ext_csd[EXT_CSD_POWER_OFF_LONG_TIME];
+ }
out:
return err;
}
@@ -710,6 +712,19 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
}

/*
+ * If the host supports the power_off_notify capability then
+ * set the notification byte in the ext_csd register of device
+ */
+ if (host->caps & MMC_CAP_POWER_OFF_NOTIFY) {
+ err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
+ EXT_CSD_POWER_OFF_NOTIFICATION,
+ EXT_CSD_POWER_ON,
+ card->ext_csd.generic_cmd6_time);
+ if (err && err != -EBADMSG)
+ goto free_card;
+ }
+
+ /*
* 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 e992fe3..2bf2843 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -53,6 +53,7 @@ struct mmc_ext_csd {
unsigned int part_time; /* Units: ms */
unsigned int sa_timeout; /* Units: 100ns */
unsigned int generic_cmd6_time; /* Units: ms */
+ unsigned int power_off_longtime; /* Units: ms */
unsigned int hs_max_dtr;
unsigned int sectors;
unsigned int card_type;
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 1d09562..cf2dadc 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -229,6 +229,7 @@ struct mmc_host {
#define MMC_CAP_MAX_CURRENT_600 (1 << 28) /* Host max current limit is 600mA */
#define MMC_CAP_MAX_CURRENT_800 (1 << 29) /* Host max current limit is 800mA */
#define MMC_CAP_CMD23 (1 << 30) /* CMD23 supported. */
+#define MMC_CAP_POWER_OFF_NOTIFY (1 << 31)/*Notify poweroff supported */

mmc_pm_flag_t pm_caps; /* supported pm features */

diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index e869f00..a788e01 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -270,6 +270,7 @@ struct _mmc_csd {
* EXT_CSD fields
*/

+#define EXT_CSD_POWER_OFF_NOTIFICATION 34 /* R/W */
#define EXT_CSD_PARTITION_ATTRIBUTE 156 /* R/W */
#define EXT_CSD_PARTITION_SUPPORT 160 /* RO */
#define EXT_CSD_WR_REL_PARAM 166 /* RO */
@@ -293,6 +294,7 @@ 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_POWER_OFF_LONG_TIME 247 /*RO*/
#define EXT_CSD_GENERIC_CMD6_TIME 248 /* RO */

/*
@@ -329,6 +331,11 @@ struct _mmc_csd {
#define EXT_CSD_SEC_BD_BLK_EN BIT(2)
#define EXT_CSD_SEC_GB_CL_EN BIT(4)

+#define EXT_CSD_NO_POWER_NOTIFICATION 0
+#define EXT_CSD_POWER_ON 1
+#define EXT_CSD_POWER_OFF_SHORT 2
+#define EXT_CSD_POWER_OFF_LONG 3
+
/*
* MMC_SWITCH access modes
*/
--
1.7.1