From: Kevin Liu <kliu5@xxxxxxxxxxx>
Add the function since MMC 1.8v signal voltage switch don't need
the same switch sequence requirements as SD/SDIO.
Signed-off-by: Kevin Liu <kliu5@xxxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 46 +++++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 45 insertions(+), 1 deletions(-)
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 14ec904..50e7a54 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1794,6 +1794,46 @@ static int sdhci_do_1_8v_signal_voltage_switch(struct sdhci_host *host,
return -EAGAIN;
}
+static int sdhci_mmc_do_1_8v_signal_voltage_switch(struct sdhci_host *host,
+ u16 ctrl)
+{
+ int ret;
+
+ if (host->vqmmc) {
+ ret = regulator_set_voltage(host->vqmmc, 1700000, 1950000);
+ if (ret) {
+ pr_warning("%s: Switching to 1.8V signalling voltage "
+ " failed\n", mmc_hostname(host->mmc));
+ return -EIO;
+ }
+ }
+
+ /*
+ * May need to apply soc/platfrom settings for the
+ * voltage switch
+ */
+ if (host->ops->signal_voltage_switch)
+ host->ops->signal_voltage_switch(host,
+ host->mmc->ios.signal_voltage);
+
+ /* Enable 1.8V Signal Enable in the Host Control2 register */
+ ctrl |= SDHCI_CTRL_VDD_180;
+ sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);
+
+ /* Wait for 5ms */
+ usleep_range(5000, 5500);
+
+ /* 1.8V regulator output should be stable within 5 ms */
+ ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ if (ctrl & SDHCI_CTRL_VDD_180)
+ return 0;
+
+ pr_warning("%s: 1.8V regulator output did not became stable\n",
+ mmc_hostname(host->mmc));
+
+ return -EIO;
+}
+
static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,
struct mmc_ios *ios)
{
@@ -1814,8 +1854,12 @@ static int sdhci_do_start_signal_voltage_switch(struct sdhci_host *host,
if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
return sdhci_do_3_3v_signal_voltage_switch(host, ctrl);
else if (!(ctrl & SDHCI_CTRL_VDD_180) &&
- (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180))
+ (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180))
return sdhci_do_1_8v_signal_voltage_switch(host, ctrl);
+ else if (!(ctrl & SDHCI_CTRL_VDD_180) &&
+ (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_MMC_180))
+ return sdhci_mmc_do_1_8v_signal_voltage_switch(host,
+ ctrl);
else
/* No signal voltage switch required */
return 0;
--
1.7.0.4
--
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