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 <mich...@walle.cc>
Fixes: 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy cards in
__mmc_switch()")
---
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 | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/mmc/host/sdhci-of-esdhc.c
b/drivers/mmc/host/sdhci-of-esdhc.c
index fb71c86..74cf3b1 100644
--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -66,6 +66,19 @@ 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 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) & 0x01000000;
+ return ret;
+ }
+
ret = value;
return ret;
}
--
2.1.4
