[PATCH 08/13] sdhci: Add get_{max,timeout}_clock callbacks

[Anton Vorontsov <avorontsov@ru.mvista.com>]

From: Ben Dooks <ben-linux@fluff.org>

Some controllers do not provide clock information in their capabilities
(in the Samsung case, it is because there are multiple clock sources
available to the controller). Add hooks to allow the system to supply
clock information.

p.s.
In the original Ben's patch there was a bug that makes sdhci_add_host()
return -ENODEV even if callbacks were specified. This is fixed now.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
---
 drivers/mmc/host/sdhci.c |   22 +++++++++++++++-------
 drivers/mmc/host/sdhci.h |    2 ++
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 1c36a25..96a0482 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1736,19 +1736,27 @@ 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) {
-		printk(KERN_ERR "%s: Hardware doesn't specify base clock "
-			"frequency.\n", mmc_hostname(mmc));
-		return -ENODEV;
+		if (!host->ops->get_max_clock) {
+			printk(KERN_ERR
+			       "%s: Hardware doesn't specify base clock "
+			       "frequency.\n", mmc_hostname(mmc));
+			return -ENODEV;
+		}
+		host->max_clk = host->ops->get_max_clock(host);
 	}
-	host->max_clk *= 1000000;
 
 	host->timeout_clk =
 		(caps & SDHCI_TIMEOUT_CLK_MASK) >> SDHCI_TIMEOUT_CLK_SHIFT;
 	if (host->timeout_clk == 0) {
-		printk(KERN_ERR "%s: Hardware doesn't specify timeout clock "
-			"frequency.\n", mmc_hostname(mmc));
-		return -ENODEV;
+		if (!host->ops->get_timeout_clock) {
+			printk(KERN_ERR
+			       "%s: Hardware doesn't specify timeout clock "
+			       "frequency.\n", mmc_hostname(mmc));
+			return -ENODEV;
+		}
+		host->timeout_clk = host->ops->get_timeout_clock(host);
 	}
 	if (caps & SDHCI_TIMEOUT_CLK_UNIT)
 		host->timeout_clk *= 1000;
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 7b115d8..ef70900 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -289,6 +289,8 @@ struct sdhci_ops {
 	void		(*writeb)(struct sdhci_host *host, u8 val, int reg);
 
 	int		(*enable_dma)(struct sdhci_host *host);
+	unsigned int	(*get_max_clock)(struct sdhci_host *host);
+	unsigned int	(*get_timeout_clock)(struct sdhci_host *host);
 };
 
 extern void sdhci_writel(struct sdhci_host *host, u32 val, int reg);
-- 
1.5.6.5