From aff5d3c83fb8c294b3c4b97c5b6386306b47f1a0 Mon Sep 17 00:00:00 2001 From: Kishon Vijay Abraham I Date: Thu, 21 Sep 2017 16:30:00 +0200 Subject: [PATCH] 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 Signed-off-by: Jean-Jacques Hiblot --- drivers/mmc/mmc.c | 16 ++++++++++++++++ include/mmc.h | 8 ++++++++ 2 files changed, 24 insertions(+) diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c index 588cfb2b2e..24b5e16a3b 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); diff --git a/include/mmc.h b/include/mmc.h index 3e57887af0..e5249637c8 100644 --- a/include/mmc.h +++ b/include/mmc.h @@ -272,6 +272,13 @@ #define ENHNCD_SUPPORT (0x2) #define PART_ENH_ATTRIB (0x1f) +enum mmc_voltage { + MMC_SIGNAL_VOLTAGE_000 = 0, + MMC_SIGNAL_VOLTAGE_120, + MMC_SIGNAL_VOLTAGE_180, + MMC_SIGNAL_VOLTAGE_330 +}; + /* Maximum block size for MMC */ #define MMC_MAX_BLOCK_LEN 512 @@ -457,6 +464,7 @@ struct mmc { int high_capacity; uint bus_width; uint clock; + enum mmc_voltage signal_voltage; uint card_caps; uint ocr; uint dsr; -- 2.39.2