From: Kishon Vijay Abraham I <[email protected]> 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 <[email protected]> Signed-off-by: Jean-Jacques Hiblot <[email protected]> --- drivers/mmc/mmc.c | 15 +++++++++++++++ include/mmc.h | 5 +++++ 2 files changed, 20 insertions(+) diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 2ae6f1c..10af81d 100644 --- a/drivers/mmc/mmc.c +++ b/drivers/mmc/mmc.c @@ -29,6 +29,7 @@ static const unsigned int sd_au_size[] = { SZ_4M / 512, SZ_8M / 512, (SZ_8M + SZ_4M) / 512, 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; @@ -1247,6 +1248,12 @@ 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, @@ -1935,6 +1942,14 @@ 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); diff --git a/include/mmc.h b/include/mmc.h index 9f20eb4..89cb26c 100644 --- a/include/mmc.h +++ b/include/mmc.h @@ -266,6 +266,10 @@ #define ENHNCD_SUPPORT (0x2) #define PART_ENH_ATTRIB (0x1f) +#define MMC_SIGNAL_VOLTAGE_330 1 +#define MMC_SIGNAL_VOLTAGE_180 2 +#define MMC_SIGNAL_VOLTAGE_120 3 + /* Maximum block size for MMC */ #define MMC_MAX_BLOCK_LEN 512 @@ -452,6 +456,7 @@ struct mmc { int high_capacity; uint bus_width; uint clock; + uint signal_voltage; uint card_caps; uint ocr; uint dsr; -- 1.9.1 _______________________________________________ U-Boot mailing list [email protected] https://lists.denx.de/listinfo/u-boot
