mmc: MMC 4.4 DDR support
Add support for Dual Data Rate MMC cards as defined in the 4.4
specification.
Signed-off-by: Hanumath Prasad <hanumath.prasad@stericsson.com>
Cc: linux-mmc@vger.kernel.org
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Tested-by Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 6570c03..66c4a59 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -258,6 +258,21 @@
}
switch (ext_csd[EXT_CSD_CARD_TYPE] & EXT_CSD_CARD_TYPE_MASK) {
+ case EXT_CSD_CARD_TYPE_DDR_52 | EXT_CSD_CARD_TYPE_52 |
+ EXT_CSD_CARD_TYPE_26:
+ card->ext_csd.hs_max_dtr = 52000000;
+ card->ext_csd.card_type = EXT_CSD_CARD_TYPE_DDR_52;
+ break;
+ case EXT_CSD_CARD_TYPE_DDR_1_2V | EXT_CSD_CARD_TYPE_52 |
+ EXT_CSD_CARD_TYPE_26:
+ card->ext_csd.hs_max_dtr = 52000000;
+ card->ext_csd.card_type = EXT_CSD_CARD_TYPE_DDR_1_2V;
+ break;
+ case EXT_CSD_CARD_TYPE_DDR_1_8V | EXT_CSD_CARD_TYPE_52 |
+ EXT_CSD_CARD_TYPE_26:
+ card->ext_csd.hs_max_dtr = 52000000;
+ card->ext_csd.card_type = EXT_CSD_CARD_TYPE_DDR_1_8V;
+ break;
case EXT_CSD_CARD_TYPE_52 | EXT_CSD_CARD_TYPE_26:
card->ext_csd.hs_max_dtr = 52000000;
break;
@@ -503,6 +518,18 @@
mmc_set_clock(host, max_dtr);
/*
+ * Activate DDR50 mode (if supported).
+ */
+ if (mmc_card_highspeed(card)) {
+ if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_8V)
+ && (host->caps & (MMC_CAP_1_8V_DDR)))
+ mmc_card_set_ddr_mode(card);
+ else if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_2V)
+ && (host->caps & (MMC_CAP_1_2V_DDR)))
+ mmc_card_set_ddr_mode(card);
+ }
+
+ /*
* Activate wide bus (if supported).
*/
if ((card->csd.mmca_vsn >= CSD_SPEC_VER_4) &&
@@ -510,10 +537,16 @@
unsigned ext_csd_bit, bus_width;
if (host->caps & MMC_CAP_8_BIT_DATA) {
- ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
+ if (mmc_card_ddr_mode(card))
+ ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_8;
+ else
+ ext_csd_bit = EXT_CSD_BUS_WIDTH_8;
bus_width = MMC_BUS_WIDTH_8;
} else {
- ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
+ if (mmc_card_ddr_mode(card))
+ ext_csd_bit = EXT_CSD_DDR_BUS_WIDTH_4;
+ else
+ ext_csd_bit = EXT_CSD_BUS_WIDTH_4;
bus_width = MMC_BUS_WIDTH_4;
}