diff options
| author | Teppei Kamijou <teppei.kamijou.yb@renesas.com> | 2012-12-12 15:38:08 +0100 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2013-02-11 12:51:24 -0500 |
| commit | 555061f987787a966b01e62517b9befbd35e2f89 (patch) | |
| tree | d43970605c7c2f4bf8178c399855697552369cf0 /drivers/mmc | |
| parent | 2cd5b3e061e3742de6b3a50f45f7d3b96aa50964 (diff) | |
| download | linux-555061f987787a966b01e62517b9befbd35e2f89.tar.bz2 | |
mmc: sh_mmcif: Add support for eMMC Dual Data Rate
Some MMCIF implementations support the Dual Data Rate. With this patch,
platforms can set the MMC_CAP_UHS_DDR50 capability flag in MMCIF platform
data. This will let the MMC core to actually use the DDR mode.
Signed-off-by: Teppei Kamijou <teppei.kamijou.yb@renesas.com>
Signed-off-by: Shinya Kuribayashi <shinya.kuribayashi.px@renesas.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc')
| -rw-r--r-- | drivers/mmc/host/sh_mmcif.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/mmc/host/sh_mmcif.c b/drivers/mmc/host/sh_mmcif.c index c7984bad8efc..6d4328dce320 100644 --- a/drivers/mmc/host/sh_mmcif.c +++ b/drivers/mmc/host/sh_mmcif.c @@ -88,6 +88,7 @@ #define CMD_SET_TBIT (1 << 7) /* 1: tran mission bit "Low" */ #define CMD_SET_OPDM (1 << 6) /* 1: open/drain */ #define CMD_SET_CCSH (1 << 5) +#define CMD_SET_DARS (1 << 2) /* Dual Data Rate */ #define CMD_SET_DATW_1 ((0 << 1) | (0 << 0)) /* 1bit */ #define CMD_SET_DATW_4 ((0 << 1) | (1 << 0)) /* 4bit */ #define CMD_SET_DATW_8 ((1 << 1) | (0 << 0)) /* 8bit */ @@ -216,6 +217,7 @@ struct sh_mmcif_host { struct clk *hclk; unsigned int clk; int bus_width; + unsigned char timing; bool sd_error; bool dying; long timeout; @@ -781,6 +783,17 @@ static u32 sh_mmcif_set_cmd(struct sh_mmcif_host *host, dev_err(&host->pd->dev, "Unsupported bus width.\n"); break; } + switch (host->timing) { + case MMC_TIMING_UHS_DDR50: + /* + * MMC core will only set this timing, if the host + * advertises the MMC_CAP_UHS_DDR50 capability. MMCIF + * implementations with this capability, e.g. sh73a0, + * will have to set it in their platform data. + */ + tmp |= CMD_SET_DARS; + break; + } } /* DWEN */ if (opc == MMC_WRITE_BLOCK || opc == MMC_WRITE_MULTIPLE_BLOCK) @@ -1002,6 +1015,7 @@ static void sh_mmcif_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) sh_mmcif_clock_control(host, ios->clock); } + host->timing = ios->timing; host->bus_width = ios->bus_width; host->state = STATE_IDLE; } |