mmc: core: add eMMC hardware reset support
eMMC's may have a hardware reset line. This patch provides a
host controller operation to implement hardware reset and
a function to reset and reinitialize the card. Also, for MMC,
the reset is always performed before initialization.
The host must set the new host capability MMC_CAP_HW_RESET
to enable hardware reset.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h
index 6dfb293..5294ddf 100644
--- a/include/linux/mmc/card.h
+++ b/include/linux/mmc/card.h
@@ -50,6 +50,7 @@
u8 rel_sectors;
u8 rel_param;
u8 part_config;
+ u8 rst_n_function;
unsigned int part_time; /* Units: ms */
unsigned int sa_timeout; /* Units: 100ns */
unsigned int hs_max_dtr;
diff --git a/include/linux/mmc/core.h b/include/linux/mmc/core.h
index b8b1b7a..56e5625 100644
--- a/include/linux/mmc/core.h
+++ b/include/linux/mmc/core.h
@@ -162,6 +162,9 @@
extern unsigned int mmc_calc_max_discard(struct mmc_card *card);
extern int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen);
+extern int mmc_hw_reset(struct mmc_host *host);
+extern int mmc_hw_reset_check(struct mmc_host *host);
+extern int mmc_can_reset(struct mmc_card *card);
extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);
extern unsigned int mmc_align_data_size(struct mmc_card *, unsigned int);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 340cc0c9..b2aefea 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -151,6 +151,7 @@
int (*execute_tuning)(struct mmc_host *host);
void (*enable_preset_value)(struct mmc_host *host, bool enable);
int (*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv);
+ void (*hw_reset)(struct mmc_host *host);
};
struct mmc_card;
@@ -233,6 +234,7 @@
#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_HW_RESET (1 << 31) /* Hardware reset */
mmc_pm_flag_t pm_caps; /* supported pm features */
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index 5a794cb..ed8fca8 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -272,6 +272,7 @@
#define EXT_CSD_PARTITION_ATTRIBUTE 156 /* R/W */
#define EXT_CSD_PARTITION_SUPPORT 160 /* RO */
+#define EXT_CSD_RST_N_FUNCTION 162 /* R/W */
#define EXT_CSD_WR_REL_PARAM 166 /* RO */
#define EXT_CSD_ERASE_GROUP_DEF 175 /* R/W */
#define EXT_CSD_PART_CONFIG 179 /* R/W */
@@ -328,6 +329,9 @@
#define EXT_CSD_SEC_BD_BLK_EN BIT(2)
#define EXT_CSD_SEC_GB_CL_EN BIT(4)
+#define EXT_CSD_RST_N_EN_MASK 0x3
+#define EXT_CSD_RST_N_ENABLED 1 /* RST_n is enabled on card */
+
/*
* MMC_SWITCH access modes
*/