From: Faiz Abbas faiz_abbas@ti.com
Add a set_voltage() function which handles the switch from 3.3V to 1.8V for SD card UHS modes.
Signed-off-by: Faiz Abbas faiz_abbas@ti.com Signed-off-by: Aswath Govindraju a-govindraju@ti.com Reviewed-by: Jaehoon Chung jh80.chung@samsung.com --- drivers/mmc/sdhci.c | 95 +++++++++++++++++++++++++++++++++++++++++++++ include/sdhci.h | 10 +++++ 2 files changed, 105 insertions(+)
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index 06289343124e..ed0dc173253b 100644 --- a/drivers/mmc/sdhci.c +++ b/drivers/mmc/sdhci.c @@ -20,6 +20,7 @@ #include <linux/delay.h> #include <linux/dma-mapping.h> #include <phys2bus.h> +#include <power/regulator.h>
static void sdhci_reset(struct sdhci_host *host, u8 mask) { @@ -509,6 +510,100 @@ void sdhci_set_uhs_timing(struct sdhci_host *host) sdhci_writew(host, reg, SDHCI_HOST_CONTROL2); }
+static void sdhci_set_voltage(struct sdhci_host *host) +{ + if (IS_ENABLED(CONFIG_MMC_IO_VOLTAGE)) { + struct mmc *mmc = (struct mmc *)host->mmc; + u32 ctrl; + + ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2); + + switch (mmc->signal_voltage) { + case MMC_SIGNAL_VOLTAGE_330: +#if CONFIG_IS_ENABLED(DM_REGULATOR) + if (mmc->vqmmc_supply) { + if (regulator_set_enable_if_allowed(mmc->vqmmc_supply, false)) { + pr_err("failed to disable vqmmc-supply\n"); + return; + } + + if (regulator_set_value(mmc->vqmmc_supply, 3300000)) { + pr_err("failed to set vqmmc-voltage to 3.3V\n"); + return; + } + + if (regulator_set_enable_if_allowed(mmc->vqmmc_supply, true)) { + pr_err("failed to enable vqmmc-supply\n"); + return; + } + } +#endif + if (IS_SD(mmc)) { + ctrl &= ~SDHCI_CTRL_VDD_180; + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2); + } + + /* Wait for 5ms */ + mdelay(5); + + /* 3.3V regulator output should be stable within 5 ms */ + if (IS_SD(mmc)) { + if (ctrl & SDHCI_CTRL_VDD_180) { + pr_err("3.3V regulator output did not become stable\n"); + return; + } + } + + break; + case MMC_SIGNAL_VOLTAGE_180: +#if CONFIG_IS_ENABLED(DM_REGULATOR) + if (mmc->vqmmc_supply) { + if (regulator_set_enable_if_allowed(mmc->vqmmc_supply, false)) { + pr_err("failed to disable vqmmc-supply\n"); + return; + } + + if (regulator_set_value(mmc->vqmmc_supply, 1800000)) { + pr_err("failed to set vqmmc-voltage to 1.8V\n"); + return; + } + + if (regulator_set_enable_if_allowed(mmc->vqmmc_supply, true)) { + pr_err("failed to enable vqmmc-supply\n"); + return; + } + } +#endif + if (IS_SD(mmc)) { + ctrl |= SDHCI_CTRL_VDD_180; + sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2); + } + + /* Wait for 5 ms */ + mdelay(5); + + /* 1.8V regulator output has to be stable within 5 ms */ + if (IS_SD(mmc)) { + if (!(ctrl & SDHCI_CTRL_VDD_180)) { + pr_err("1.8V regulator output did not become stable\n"); + return; + } + } + + break; + default: + /* No signal voltage switch required */ + return; + } + } +} + +void sdhci_set_control_reg(struct sdhci_host *host) +{ + sdhci_set_voltage(host); + sdhci_set_uhs_timing(host); +} + #ifdef CONFIG_DM_MMC static int sdhci_set_ios(struct udevice *dev) { diff --git a/include/sdhci.h b/include/sdhci.h index 3e5a64981857..0ae9471ad749 100644 --- a/include/sdhci.h +++ b/include/sdhci.h @@ -491,6 +491,16 @@ void sdhci_set_uhs_timing(struct sdhci_host *host); /* Export the operations to drivers */ int sdhci_probe(struct udevice *dev); int sdhci_set_clock(struct mmc *mmc, unsigned int clock); + +/** + * sdhci_set_control_reg - Set control registers + * + * This is used set up control registers for voltage level and UHS speed + * mode. + * + * @host: SDHCI host structure + */ +void sdhci_set_control_reg(struct sdhci_host *host); extern const struct dm_mmc_ops sdhci_ops; #else #endif