set the callback for signaling voltage for Dual Data Rate.
The controller requires V18_EN be set for DDR to work. The
bit enables DDR but does not affect any signaling voltages.
no mdelay is needed.
Signed-off-by: Philip Rakity <prakity@xxxxxxxxxxx>
---
drivers/mmc/host/sdhci-pxa.c | 15 +++++++++++++++
1 files changed, 15 insertions(+), 0 deletions(-)
diff --git a/drivers/mmc/host/sdhci-pxa.c b/drivers/mmc/host/sdhci-pxa.c
index 5a61208..8f9a04e 100644
--- a/drivers/mmc/host/sdhci-pxa.c
+++ b/drivers/mmc/host/sdhci-pxa.c
@@ -69,8 +69,23 @@ static void set_clock(struct sdhci_host *host, unsigned int clock)
}
}
+static unsigned int set_signaling_voltage(struct sdhci_host *host,
+ unsigned int ddr)
+{
+ u16 con;
+ /*
+ * Set V18_EN -- DDR does not work without this.
+ * does not change signaling voltage
+ */
+ con = readw(host->ioaddr + SDHCI_HOST_CONTROL_2);
+ con |= SDCTRL_2_SDH_V18_EN;
+ writew(con, host->ioaddr + SDHCI_HOST_CONTROL_2);
+ return 0;
+}
+
static struct sdhci_ops sdhci_pxa_ops = {
.set_clock = set_clock,
+ .set_signaling_voltage = set_signaling_voltage,
};
/*****************************************************************************\
--
1.7.0.4
--
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