[PATCH] mmc: mmci: Support for DDR mode

Ulf Hansson ulf.hansson at stericsson.com
Wed Dec 12 09:59:08 EST 2012


From: Ulf Hansson <ulf.hansson at linaro.org>

Add support for DDR mode which may be used for the ux500v2 variant.
Corresponding capabilities to enable the DDR support must be set in
the platform struct to enable the functionality.

Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
---
 drivers/mmc/host/mmci.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index aa04b42..4e4f5f1 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -202,6 +202,9 @@ static void mmci_set_clkreg(struct mmci_host *host, unsigned int desired)
 	if (host->mmc->ios.bus_width == MMC_BUS_WIDTH_8)
 		clk |= MCI_ST_8BIT_BUS;
 
+	if (host->mmc->ios.timing == MMC_TIMING_UHS_DDR50)
+		clk |= MCI_ST_UX500_NEG_EDGE;
+
 	mmci_write_clkreg(host, clk);
 }
 
@@ -680,6 +683,9 @@ static void mmci_start_data(struct mmci_host *host, struct mmc_data *data)
 			mmci_write_clkreg(host, clk);
 		}
 
+	if (host->mmc->ios.timing == MMC_TIMING_UHS_DDR50)
+		datactrl |= MCI_ST_DPSM_DDRMODE;
+
 	/*
 	 * Attempt to use DMA operation mode, if this
 	 * should fail, fall back to PIO mode
-- 
1.7.10




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