[PATCH v5 5/9] mmc: sdhci-st: Add sdhci_st_set_uhs_signaling function.

Peter Griffin
2015-04-10T09:42:34Z

To allow UHS modes to work properly we need to provide the st specific
set_uhs_signaling callback function. This function differs from the
generic sdhci_set_uhs_signaling callback in that we need to configure
the correct delay depending on the UHS mode, and also set the V18_EN
bit.

Signed-off-by: Peter Griffin <peter.griffin@linaro.org>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Acked-by: Maxime Coquelin <maxime.coquelin@st.com>
---
drivers/mmc/host/sdhci-st.c | 51 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)

diff --git a/drivers/mmc/host/sdhci-st.c b/drivers/mmc/host/sdhci-st.c
index 10989ed..42a361c 100644
--- a/drivers/mmc/host/sdhci-st.c
+++ b/drivers/mmc/host/sdhci-st.c
@@ -261,6 +261,56 @@ static int sdhci_st_set_dll_for_clock(struct sdhci_host *host)
return ret;
}

+static void sdhci_st_set_uhs_signaling(struct sdhci_host *host,
+ unsigned int uhs)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct st_mmc_platform_data *pdata = pltfm_host->priv;
+ u16 ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ int ret = 0;
+
+ /* Select Bus Speed Mode for host */
+ ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
+ switch (uhs) {
+ /*
+ * Set V18_EN -- UHS modes do not work without this.
+ * does not change signaling voltage
+ */
+
+ case MMC_TIMING_UHS_SDR12:
+ st_mmcss_set_static_delay(pdata->top_ioaddr);
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR12 | SDHCI_CTRL_VDD_180;
+ break;
+ case MMC_TIMING_UHS_SDR25:
+ st_mmcss_set_static_delay(pdata->top_ioaddr);
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR25 | SDHCI_CTRL_VDD_180;
+ break;
+ case MMC_TIMING_UHS_SDR50:
+ st_mmcss_set_static_delay(pdata->top_ioaddr);
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR50 | SDHCI_CTRL_VDD_180;
+ ret = sdhci_st_set_dll_for_clock(host);
+ break;
+ case MMC_TIMING_UHS_SDR104:
+ case MMC_TIMING_MMC_HS200:
+ st_mmcss_set_static_delay(pdata->top_ioaddr);
+ ctrl_2 |= SDHCI_CTRL_UHS_SDR104 | SDHCI_CTRL_VDD_180;
+ ret = sdhci_st_set_dll_for_clock(host);
+ break;
+ case MMC_TIMING_UHS_DDR50:
+ case MMC_TIMING_MMC_DDR52:
+ st_mmcss_set_static_delay(pdata->top_ioaddr);
+ ctrl_2 |= SDHCI_CTRL_UHS_DDR50 | SDHCI_CTRL_VDD_180;
+ break;
+ }
+
+ if (ret)
+ dev_warn(mmc_dev(host->mmc), "Error setting dll for clock "
+ "(uhs %d)\n", uhs);
+
+ dev_dbg(mmc_dev(host->mmc), "uhs %d, ctrl_2 %04X\n", uhs, ctrl_2);
+
+ sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+}

static u32 sdhci_st_readl(struct sdhci_host *host, int reg)
{
@@ -284,6 +334,7 @@ static const struct sdhci_ops sdhci_st_ops = {
.set_bus_width = sdhci_set_bus_width,
.read_l = sdhci_st_readl,
.reset = sdhci_reset,
+ .set_uhs_signaling = sdhci_st_set_uhs_signaling,
};

static const struct sdhci_pltfm_data sdhci_st_pdata = {
--
1.9.1