[PATCH 1/3] sdhci: Implement CAP_CLOCK_BASE_BROKEN quirk

From: Anton Vorontsov
Date: Fri Feb 19 2010 - 14:48:35 EST


Some hosts (e.g. as found in CNS3xxx SOCs) report wrong value in
CLOCK_BASE capability field, and currently there is no way to
force the SDHCI core to use the platform-provided base clock value.

This patch implements CAP_CLOCK_BASE_BROKEN quirk. When enabled,
the SDHCI core will always use base clock frequency provided by
the platform.

Signed-off-by: Anton Vorontsov <avorontsov@xxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci.c | 3 ++-
drivers/mmc/host/sdhci.h | 2 ++
2 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index c279fbc..aedf4a1 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1745,7 +1745,8 @@ int sdhci_add_host(struct sdhci_host *host)
host->max_clk =
(caps & SDHCI_CLOCK_BASE_MASK) >> SDHCI_CLOCK_BASE_SHIFT;
host->max_clk *= 1000000;
- if (host->max_clk == 0) {
+ if (host->max_clk == 0 || host->quirks &
+ SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN) {
if (!host->ops->get_max_clock) {
printk(KERN_ERR
"%s: Hardware doesn't specify base clock "
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 842f46f..831bf7f 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -236,6 +236,8 @@ struct sdhci_host {
#define SDHCI_QUIRK_DELAY_AFTER_POWER (1<<23)
/* Controller uses SDCLK instead of TMCLK for data timeouts */
#define SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK (1<<24)
+/* Controller reports wrong base clock capability */
+#define SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN (1<<25)

int irq; /* Device IRQ */
void __iomem * ioaddr; /* Mapped address */
--
1.7.0

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