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>
This commit is contained in:
Adrian Hunter
2011-08-29 16:42:11 +03:00
committed by Chris Ball
parent 8e3336b1e4
commit b2499518b5
6 changed files with 107 additions and 1 deletions

View File

@@ -151,6 +151,7 @@ struct mmc_host_ops {
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 @@ 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_HW_RESET (1 << 31) /* Hardware reset */
mmc_pm_flag_t pm_caps; /* supported pm features */