To prepare the voltage switch procedure, the VSWITCHEN bit must be
set before sending the cmd11.
To confirm completion of voltage switch, the VSWEND flag must be
checked.
Signed-off-by: Ludovic Barre <ludovic.barre@xxxxxx>
---
drivers/mmc/host/mmci.h | 4 +++
drivers/mmc/host/mmci_stm32_sdmmc.c | 40 ++++++++++++++++++++++++++++-
2 files changed, 43 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/mmci.h b/drivers/mmc/host/mmci.h
index c04a144259a2..3634f98ad2d8 100644
--- a/drivers/mmc/host/mmci.h
+++ b/drivers/mmc/host/mmci.h
@@ -165,6 +165,7 @@
/* Extended status bits for the STM32 variants */
#define MCI_STM32_BUSYD0 BIT(20)
#define MCI_STM32_BUSYD0END BIT(21)
+#define MCI_STM32_VSWEND BIT(25)
#define MMCICLEAR 0x038
#define MCI_CMDCRCFAILCLR (1 << 0)
@@ -182,6 +183,9 @@
#define MCI_ST_SDIOITC (1 << 22)
#define MCI_ST_CEATAENDC (1 << 23)
#define MCI_ST_BUSYENDC (1 << 24)
+/* Extended clear bits for the STM32 variants */
+#define MCI_STM32_VSWENDC BIT(25)
+#define MCI_STM32_CKSTOPC BIT(26)
#define MMCIMASK0 0x03c
#define MCI_CMDCRCFAILMASK (1 << 0)
diff --git a/drivers/mmc/host/mmci_stm32_sdmmc.c b/drivers/mmc/host/mmci_stm32_sdmmc.c
index 10059fa19f4a..9f43cf947c5f 100644
--- a/drivers/mmc/host/mmci_stm32_sdmmc.c
+++ b/drivers/mmc/host/mmci_stm32_sdmmc.c
@@ -263,7 +263,9 @@ static void mmci_sdmmc_set_pwrreg(struct mmci_host *host, unsigned int pwr)
struct mmc_ios ios = host->mmc->ios;
struct sdmmc_dlyb *dlyb = host->variant_priv;
- pwr = host->pwr_reg_add;
+ /* adds OF options and preserves voltage switch bits */
+ pwr = host->pwr_reg_add |
+ (host->pwr_reg & (MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
sdmmc_dlyb_input_ck(dlyb);
@@ -454,6 +456,40 @@ static int sdmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
return sdmmc_dlyb_phase_tuning(host, opcode);
}
+static void sdmmc_prep_vswitch(struct mmci_host *host)
+{
+ /* clear the voltage switch completion flag */
+ writel_relaxed(MCI_STM32_VSWENDC, host->base + MMCICLEAR);
+ /* enable Voltage switch procedure */
+ mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCHEN);
+}
+
+static int sdmmc_vswitch(struct mmci_host *host, struct mmc_ios *ios)
+{
+ unsigned long flags;
+ u32 status;
+ int ret = 0;
+
+ if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180) {
+ spin_lock_irqsave(&host->lock, flags);
+ mmci_write_pwrreg(host, host->pwr_reg | MCI_STM32_VSWITCH);
+ spin_unlock_irqrestore(&host->lock, flags);
+
+ /* wait voltage switch completion while 10ms */
+ ret = readl_relaxed_poll_timeout(host->base + MMCISTATUS,
+ status,
+ (status & MCI_STM32_VSWEND),
+ 10, 10000);
+
+ writel_relaxed(MCI_STM32_VSWENDC | MCI_STM32_CKSTOPC,
+ host->base + MMCICLEAR);
+ mmci_write_pwrreg(host, host->pwr_reg &
+ ~(MCI_STM32_VSWITCHEN | MCI_STM32_VSWITCH));
+ }
+
+ return ret;
+}
+
static struct mmci_host_ops sdmmc_variant_ops = {
.validate_data = sdmmc_idma_validate_data,
.prep_data = sdmmc_idma_prep_data,
@@ -465,6 +501,8 @@ static struct mmci_host_ops sdmmc_variant_ops = {
.set_clkreg = mmci_sdmmc_set_clkreg,
.set_pwrreg = mmci_sdmmc_set_pwrreg,
.busy_complete = sdmmc_busy_complete,
+ .prep_volt_switch = sdmmc_prep_vswitch,
+ .volt_switch = sdmmc_vswitch,
};
void sdmmc_variant_init(struct mmci_host *host)
--
2.17.1
