aboutsummaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
Diffstat (limited to 'drivers')
-rw-r--r--drivers/mmc/mmc.c16
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 588cfb2..24b5e16 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -30,6 +30,8 @@ static const unsigned int sd_au_size[] = {
SZ_16M / 512, (SZ_16M + SZ_8M) / 512, SZ_32M / 512, SZ_64M / 512,
};
+static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage);
+
#if CONFIG_IS_ENABLED(MMC_TINY)
static struct mmc mmc_static;
struct mmc *find_mmc_device(int dev_num)
@@ -1257,6 +1259,12 @@ struct mode_width_tuning {
uint widths;
};
+static int mmc_set_signal_voltage(struct mmc *mmc, uint signal_voltage)
+{
+ mmc->signal_voltage = signal_voltage;
+ return mmc_set_ios(mmc);
+}
+
static const struct mode_width_tuning sd_modes_by_pref[] = {
{
.mode = SD_HS,
@@ -1964,6 +1972,14 @@ int mmc_start_init(struct mmc *mmc)
return err;
#endif
mmc->ddr_mode = 0;
+
+ /* First try to set 3.3V. If it fails set to 1.8V */
+ err = mmc_set_signal_voltage(mmc, MMC_SIGNAL_VOLTAGE_330);
+ if (err != 0)
+ err = mmc_set_signal_voltage(mmc, MMC_SIGNAL_VOLTAGE_180);
+ if (err != 0)
+ printf("failed to set signal voltage\n");
+
mmc_set_bus_width(mmc, 1);
mmc_set_clock(mmc, 1);