mmc: sdhci: change sdhci-pltfm into a module

There are a couple of problems left from the sdhci pltfm and OF
consolidation changes.

* When building more than one sdhci-pltfm based drivers in the same
  image, linker will give multiple definition error on the sdhci-pltfm
  helper functions.  For example right now, building sdhci-of-esdhc
  and sdhci-of-hlwd together is a valid combination from Kconfig view.

* With the current build method, there is error with building the
  drivers as module, but module installation fails with modprobe.

The patch fixes above problems by changing sdhci-pltfm into a module.
To avoid EXPORT_SYMBOL on so many big endian IO accessors, it moves
these accessors into sdhci-pltfm.h as the 'static inline' functions.
As a result, sdhci.h needs to be included in sdhci-pltfm.h, and in
turn can be removed from individual drivers which already include
sdhci-pltfm.h.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 58 insertions, 9 deletions

diff --git a/drivers/mmc/host/sdhci-pltfm.h b/drivers/mmc/host/sdhci-pltfm.h
index fd726948641a..3a9fc3f40840 100644
--- a/drivers/mmc/host/sdhci-pltfm.h
+++ b/drivers/mmc/host/sdhci-pltfm.h
@@ -12,9 +12,8 @@
 #define _DRIVERS_MMC_SDHCI_PLTFM_H
 
 #include <linux/clk.h>
-#include <linux/types.h>
 #include <linux/platform_device.h>
-#include <linux/mmc/sdhci.h>
+#include "sdhci.h"
 
 struct sdhci_pltfm_data {
 	struct sdhci_ops *ops;
@@ -31,13 +30,63 @@ struct sdhci_pltfm_host {
 };
 
 #ifdef CONFIG_MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
-extern u32 sdhci_be32bs_readl(struct sdhci_host *host, int reg);
-extern u16 sdhci_be32bs_readw(struct sdhci_host *host, int reg);
-extern u8 sdhci_be32bs_readb(struct sdhci_host *host, int reg);
-extern void sdhci_be32bs_writel(struct sdhci_host *host, u32 val, int reg);
-extern void sdhci_be32bs_writew(struct sdhci_host *host, u16 val, int reg);
-extern void sdhci_be32bs_writeb(struct sdhci_host *host, u8 val, int reg);
-#endif
+/*
+ * These accessors are designed for big endian hosts doing I/O to
+ * little endian controllers incorporating a 32-bit hardware byte swapper.
+ */
+static inline u32 sdhci_be32bs_readl(struct sdhci_host *host, int reg)
+{
+	return in_be32(host->ioaddr + reg);
+}
+
+static inline u16 sdhci_be32bs_readw(struct sdhci_host *host, int reg)
+{
+	return in_be16(host->ioaddr + (reg ^ 0x2));
+}
+
+static inline u8 sdhci_be32bs_readb(struct sdhci_host *host, int reg)
+{
+	return in_8(host->ioaddr + (reg ^ 0x3));
+}
+
+static inline void sdhci_be32bs_writel(struct sdhci_host *host,
+				       u32 val, int reg)
+{
+	out_be32(host->ioaddr + reg, val);
+}
+
+static inline void sdhci_be32bs_writew(struct sdhci_host *host,
+				       u16 val, int reg)
+{
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	int base = reg & ~0x3;
+	int shift = (reg & 0x2) * 8;
+
+	switch (reg) {
+	case SDHCI_TRANSFER_MODE:
+		/*
+		 * Postpone this write, we must do it together with a
+		 * command write that is down below.
+		 */
+		pltfm_host->xfer_mode_shadow = val;
+		return;
+	case SDHCI_COMMAND:
+		sdhci_be32bs_writel(host,
+				    val << 16 | pltfm_host->xfer_mode_shadow,
+				    SDHCI_TRANSFER_MODE);
+		return;
+	}
+	clrsetbits_be32(host->ioaddr + base, 0xffff << shift, val << shift);
+}
+
+static inline void sdhci_be32bs_writeb(struct sdhci_host *host, u8 val, int reg)
+{
+	int base = reg & ~0x3;
+	int shift = (reg & 0x3) * 8;
+
+	clrsetbits_be32(host->ioaddr + base , 0xff << shift, val << shift);
+}
+#endif /* CONFIG_MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER */
 
 extern void sdhci_get_of_property(struct platform_device *pdev);