Re: [PATCH v2] mmc: sdhci: add quirk for ACMD23 broken

From: Scott Branden
Date: Wed Dec 17 2014 - 13:37:20 EST


Hi Chris,

I have not received any feedback on this patch for the SDHCI controller. Anything I can do to help get this accepted into the codebase?

Thanks,
Scott

On 14-12-04 04:16 PM, Scott Branden wrote:
Add quirk to handle broken auto-CMD23.
Some controllers do not respond after the first auto-CMD23 is issued.

This allows CMD23 to still work (mandatory for the faster UHS-I mode)
rather than disabling CMD23 entirely via SDHCI_QUIRK2_HOST_NO_CMD23.

Signed-off by: Corneliu Doban <cdoban@xxxxxxxxxxxx>
Signed-off-by: Scott Branden <sbranden@xxxxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 3 ++-
include/linux/mmc/sdhci.h | 2 ++
2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index ada1a3e..b37331f 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2985,7 +2985,8 @@ int sdhci_add_host(struct sdhci_host *host)
/* Auto-CMD23 stuff only works in ADMA or PIO. */
if ((host->version >= SDHCI_SPEC_300) &&
((host->flags & SDHCI_USE_ADMA) ||
- !(host->flags & SDHCI_USE_SDMA))) {
+ !(host->flags & SDHCI_USE_SDMA)) &&
+ !(host->quirks2 & SDHCI_QUIRK2_ACMD23_BROKEN)) {
host->flags |= SDHCI_AUTO_CMD23;
DBG("%s: Auto-CMD23 available\n", mmc_hostname(mmc));
} else {
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index dba793e..d979cf9 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -100,6 +100,8 @@ struct sdhci_host {
#define SDHCI_QUIRK2_BROKEN_DDR50 (1<<7)
/* Stop command (CMD12) can set Transfer Complete when not using MMC_RSP_BUSY */
#define SDHCI_QUIRK2_STOP_WITH_TC (1<<8)
+/* Controller broken with using ACMD23 */
+#define SDHCI_QUIRK2_ACMD23_BROKEN (1<<9)

int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */



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