drivers/mmc/core/core.c | 38 ++++++++++++++++++++++++--------------
drivers/mmc/core/core.h | 1 +
drivers/mmc/core/sd.c | 47 +++++++++++++++++++++++++++++++++++++++++++++--
3 files changed, 70 insertions(+), 16 deletions(-)
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 24a73f387482..161c1d105d91 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1723,11 +1723,33 @@ int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage)
}
+int mmc_host_set_uhs_voltage(struct mmc_host *host)
+{
+ u32 clock;
+
+ /*
+ * During a signal voltage level switch, the clock must be gated
+ * for 5 ms according to the SD spec
+ */
+ clock = host->ios.clock;
+ host->ios.clock = 0;
+ mmc_set_ios(host);
+
+ if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180))
+ return -EAGAIN;
+
+ /* Keep clock gated for at least 10 ms, though spec only says 5 ms */
+ mmc_delay(10);
+ host->ios.clock = clock;
+ mmc_set_ios(host);
+
+ return 0;
+}
+
int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
{
struct mmc_command cmd = {};
int err = 0;
- u32 clock;
/*
* If we cannot switch voltages, return failure so the caller
@@ -1759,15 +1781,8 @@ int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
err = -EAGAIN;
goto power_cycle;
}
- /*
- * During a signal voltage level switch, the clock must be gated
- * for 5 ms according to the SD spec
- */
- clock = host->ios.clock;
- host->ios.clock = 0;
- mmc_set_ios(host);
- if (mmc_set_signal_voltage(host, MMC_SIGNAL_VOLTAGE_180)) {
+ if (mmc_host_set_uhs_voltage(host)) {
/*
* Voltages may not have been switched, but we've already
* sent CMD11, so a power cycle is required anyway
@@ -1776,11 +1791,6 @@ int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr)
goto power_cycle;
}
- /* Keep clock gated for at least 10 ms, though spec only says 5 ms */
- mmc_delay(10);
- host->ios.clock = clock;
- mmc_set_ios(host);
-
/* Wait for at least 1 ms according to spec */
mmc_delay(1);
diff --git a/drivers/mmc/core/core.h b/drivers/mmc/core/core.h
index 03e0f8384b1c..2b2690d0d877 100644
--- a/drivers/mmc/core/core.h
+++ b/drivers/mmc/core/core.h
@@ -51,6 +51,7 @@ struct device_node *mmc_of_find_child_device(struct mmc_host *host,
void mmc_set_bus_width(struct mmc_host *host, unsigned int width);
u32 mmc_select_voltage(struct mmc_host *host, u32 ocr);
int mmc_set_uhs_voltage(struct mmc_host *host, u32 ocr);
+int mmc_host_set_uhs_voltage(struct mmc_host *host);
int mmc_set_signal_voltage(struct mmc_host *host, int signal_voltage);
void mmc_set_timing(struct mmc_host *host, unsigned int timing);
void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type);
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 4fd1620b732d..35e1f52cb3f9 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -908,6 +908,18 @@ unsigned mmc_sd_get_max_clock(struct mmc_card *card)
return max_dtr;
}
+static bool mmc_sd_card_using_v18(struct mmc_card *card)
+{
+ /*
+ * According to the SD spec., the Bus Speed Mode (function group 1) bits
+ * 2 to 4 are zero if the card is initialized at 3.3V signal level. Thus
+ * they can be used to determine if the card has already switched to
+ * 1.8V signaling.
+ */
+ return card->sw_caps.sd3_bus_mode &
+ (SD_MODE_UHS_SDR50 | SD_MODE_UHS_SDR104 | SD_MODE_UHS_DDR50);
+}
+
/*
* Handle the detection and initialisation of a card.
*
@@ -921,9 +933,10 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
int err;
u32 cid[4];
u32 rocr = 0;
+ bool v18_fixup_failed = false;
WARN_ON(!host->claimed);
-
+retry:
err = mmc_sd_get_cid(host, ocr, cid, &rocr);
if (err)
return err;
@@ -989,6 +1002,36 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
if (err)
goto free_card;
+ /*
+ * If the card has not been power cycled, it may still be using 1.8V
+ * signaling. Detect that situation and try to initialize a UHS-I (1.8V)
+ * transfer mode.
+ */
+ if (!v18_fixup_failed && !mmc_host_is_spi(host) && mmc_host_uhs(host) &&
+ mmc_sd_card_using_v18(card) &&
+ host->ios.signal_voltage != MMC_SIGNAL_VOLTAGE_180) {
+ /*
+ * Re-read switch information in case it has changed since
+ * oldcard was initialized.
+ */
+ if (oldcard) {
+ err = mmc_read_switch(card);
+ if (err)
+ goto free_card;
+ }
+ if (mmc_sd_card_using_v18(card)) {
+ if (mmc_host_set_uhs_voltage(host) ||
+ mmc_sd_init_uhs_card(card)) {
+ v18_fixup_failed = true;
+ mmc_power_cycle(host, ocr);
+ if (!oldcard)
+ mmc_remove_card(card);
+ goto retry;
+ }
+ goto done;
+ }
+ }
+
/* Initialization sequence for UHS-I cards */
if (rocr & SD_ROCR_S18A) {
err = mmc_sd_init_uhs_card(card);
@@ -1021,7 +1064,7 @@ static int mmc_sd_init_card(struct mmc_host *host, u32 ocr,
mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
}
}
-
+done:
host->card = card;
return 0;
