Since commit 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy
cards in __mmc_switch()") the ESDHC driver is broken:
mmc0: Card stuck in programming state! __mmc_switch
mmc0: error -110 whilst initialising MMC card
Since this commit __mmc_switch() uses ->card_busy(), which is
sdhci_card_busy() for the esdhc driver. sdhci_card_busy() uses the
PRESENT_STATE register, specifically the DAT0 signal level bit. But the
ESDHC uses a non-conformant PRESENT_STATE register, thus a read fixup is
required to make the driver work again.
Signed-off-by: Michael Walle <michael@xxxxxxxx>
Fixes: 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy cards in __mmc_switch()")
Acked-by: Yangbo Lu <yangbo.lu@xxxxxxx>
---
v4:
- add and use SDHCI_CMD_LVL macro
- fix typo in comment, thanks alex
- add acked-by
v3:
- explain the bits in the comments
- use bits[19:0] from the original value, all other will be taken from the
fixup value.
v2:
- use lower bits of the original value (that was actually a typo)
- add fixes tag
- fix typo
drivers/mmc/host/sdhci-of-esdhc.c | 14 ++++++++++++++
drivers/mmc/host/sdhci.h | 1 +
2 files changed, 15 insertions(+)
diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
index fb71c86..1bb11e4 100644
--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -66,6 +66,20 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host,
return ret;
}
}
+ /*
+ * The DAT[3:0] line signal levels and the CMD line signal level are
+ * not compatible with standard SDHC register. The line signal levels
+ * DAT[7:0] are at bits 31:24 and the command line signal level is at
+ * bit 23. All other bits are the same as in the standard SDHC
+ * register.
+ */
+ if (spec_reg == SDHCI_PRESENT_STATE) {
+ ret = value & 0x000fffff;
+ ret |= (value >> 4) & SDHCI_DATA_LVL_MASK;
+ ret |= (value << 1) & SDHCI_CMD_LVL;
+ return ret;
+ }
+
ret = value;
return ret;
}
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index c722cd2..ea38962 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -73,6 +73,7 @@
#define SDHCI_DATA_LVL_MASK 0x00F00000
#define SDHCI_DATA_LVL_SHIFT 20
#define SDHCI_DATA_0_LVL_MASK 0x00100000
+#define SDHCI_CMD_LVL 0x01000000
#define SDHCI_HOST_CONTROL 0x28
#define SDHCI_CTRL_LED 0x01
--
2.1.4
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