diff options
| author | Kishon Vijay Abraham I | 2017-09-21 16:30:00 +0200 |
|---|---|---|
| committer | Jaehoon Chung | 2018-01-12 18:11:04 +0900 |
| commit | aff5d3c83fb8c294b3c4b97c5b6386306b47f1a0 (patch) | |
| tree | 77ca6c45a1fe42319577c1e6ca456c6dfab8c925 /drivers | |
| parent | 2a4d212f7110712f51ae8af73abbdb0ae2af0814 (diff) | |
mmc: Enable signal voltage to be selected from mmc core
Add a new function *mmc_set_signal_voltage* in mmc core
which can be used during mmc initialization to select the
signal voltage. Platform driver should use the set_ios
callback function to select the signal voltage.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/mmc.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 588cfb2b2e3..24b5e16a3bf 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); |