[PATCH 03/12] mmc: sdhci-omap: Add custom set_uhs_signaling sdhci_host ops

From: Kishon Vijay Abraham I
Date: Thu Dec 14 2017 - 08:11:20 EST


UHS-1 DDR50 and MMC DDR52 mode require DDR bit to be
set in the configuration register (MMCHS_CON). Add
sdhci-omap specific set_uhs_signaling ops to set
this bit. Also while setting the UHSMS bit, clock should be
disabled.

Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
---
drivers/mmc/host/sdhci-omap.c | 26 +++++++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-omap.c b/drivers/mmc/host/sdhci-omap.c
index defe4eac020d..8f7239e2edc2 100644
--- a/drivers/mmc/host/sdhci-omap.c
+++ b/drivers/mmc/host/sdhci-omap.c
@@ -31,6 +31,7 @@
#define SDHCI_OMAP_CON 0x12c
#define CON_DW8 BIT(5)
#define CON_DMA_MASTER BIT(20)
+#define CON_DDR BIT(19)
#define CON_CLKEXTFREE BIT(16)
#define CON_PADEN BIT(15)
#define CON_INIT BIT(1)
@@ -93,6 +94,9 @@ struct sdhci_omap_host {
u8 power_mode;
};

+static void sdhci_omap_start_clock(struct sdhci_omap_host *omap_host);
+static void sdhci_omap_stop_clock(struct sdhci_omap_host *omap_host);
+
static inline u32 sdhci_omap_readl(struct sdhci_omap_host *host,
unsigned int offset)
{
@@ -471,6 +475,26 @@ static void sdhci_omap_init_74_clocks(struct sdhci_host *host, u8 power_mode)
enable_irq(host->irq);
}

+static void sdhci_omap_set_uhs_signaling(struct sdhci_host *host,
+ unsigned int timing)
+{
+ u32 reg;
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct sdhci_omap_host *omap_host = sdhci_pltfm_priv(pltfm_host);
+
+ sdhci_omap_stop_clock(omap_host);
+
+ reg = sdhci_omap_readl(omap_host, SDHCI_OMAP_CON);
+ if (timing == MMC_TIMING_UHS_DDR50 || timing == MMC_TIMING_MMC_DDR52)
+ reg |= CON_DDR;
+ else
+ reg &= ~CON_DDR;
+ sdhci_omap_writel(omap_host, SDHCI_OMAP_CON, reg);
+
+ sdhci_set_uhs_signaling(host, timing);
+ sdhci_omap_start_clock(omap_host);
+}
+
static struct sdhci_ops sdhci_omap_ops = {
.set_clock = sdhci_omap_set_clock,
.set_power = sdhci_omap_set_power,
@@ -480,7 +504,7 @@ static struct sdhci_ops sdhci_omap_ops = {
.set_bus_width = sdhci_omap_set_bus_width,
.platform_send_init_74_clocks = sdhci_omap_init_74_clocks,
.reset = sdhci_reset,
- .set_uhs_signaling = sdhci_set_uhs_signaling,
+ .set_uhs_signaling = sdhci_omap_set_uhs_signaling,
};

static int sdhci_omap_set_capabilities(struct sdhci_omap_host *omap_host)
--
2.11.0