[PATCH] sdhci: Add a quirk to disable write-protect

From: Mike Looijmans
Date: Mon Feb 24 2014 - 02:00:49 EST


When a board does not have the WP line wired at all, the card
may be detected as read-only. Add a quirk and a device property
to disable WP detection.

Signed-off-by: Mike Looijmans <mike.looijmans@xxxxxxxx>
---
drivers/mmc/host/sdhci-pltfm.c | 3 +++
drivers/mmc/host/sdhci.c | 3 ++-
include/linux/mmc/sdhci.h | 2 ++
3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-pltfm.c b/drivers/mmc/host/sdhci-pltfm.c
index e2065a4..9e83ada 100644
--- a/drivers/mmc/host/sdhci-pltfm.c
+++ b/drivers/mmc/host/sdhci-pltfm.c
@@ -83,6 +83,9 @@ void sdhci_get_of_property(struct platform_device *pdev)
if (sdhci_of_wp_inverted(np))
host->quirks |= SDHCI_QUIRK_INVERTED_WRITE_PROTECT;

+ if (of_get_property(np, "disable-wp", NULL))
+ host->quirks2 |= SDHCI_QUIRK2_DISABLE_WP;
+
if (of_get_property(np, "broken-cd", NULL))
host->quirks |= SDHCI_QUIRK_BROKEN_CARD_DETECTION;

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 7a7fb4f..68f47fc 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1635,7 +1635,8 @@ static int sdhci_check_ro(struct sdhci_host *host)

spin_lock_irqsave(&host->lock, flags);

- if (host->flags & SDHCI_DEVICE_DEAD)
+ if ((host->flags & SDHCI_DEVICE_DEAD) ||
+ (host->quirks2 & SDHCI_QUIRK2_DISABLE_WP))
is_readonly = 0;
else if (host->ops->get_ro)
is_readonly = host->ops->get_ro(host);
diff --git a/include/linux/mmc/sdhci.h b/include/linux/mmc/sdhci.h
index 3e781b8..967dba0 100644
--- a/include/linux/mmc/sdhci.h
+++ b/include/linux/mmc/sdhci.h
@@ -98,6 +98,8 @@ struct sdhci_host {
#define SDHCI_QUIRK2_CARD_ON_NEEDS_BUS_ON (1<<4)
/* Controller has a non-standard host control register */
#define SDHCI_QUIRK2_BROKEN_HOST_CONTROL (1<<5)
+/* Controller lacks write protect detection */
+#define SDHCI_QUIRK2_DISABLE_WP (1<<6)

int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
1.7.9.5

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