Hi Aswath,
On 1/29/21 11:47 PM, Aswath Govindraju wrote:
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
drivers/mmc/sdhci.c | 73 +++++++++++++++++++++++++++++++++++++++++++++ include/sdhci.h | 10 +++++++ 2 files changed, 83 insertions(+)
diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index 06289343124e..276b6a08e571 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 +510,78 @@ 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
/* 3.3V regulator output should be stable within 5 ms */mdelay(5);if (IS_SD(mmc)) {ctrl &= ~SDHCI_CTRL_VDD_180;sdhci_writew(host, ctrl, SDHCI_HOST_CONTROL2);}
According to Specification, after Signal bit was changed to 0 from 1, it needs to wait for stable within 5ms. Isn't it right that mdelay(5) locates at here?
Best Regards, Jaehoon Chung
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);}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