usb: musb: Add context save and restore support

Adding support for MUSB register save and restore during system
suspend and resume.

Changes:
        - Added musb_save/restore_context() functions
        - Added platform specific musb_platform_save/restore_context()
          to handle platform specific jobs.
        - Maintaining BlackFin compatibility by adding read/write
          functions for registers which are not available in BlackFin

Tested system suspend and resume on OMAP3EVM board.

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/musb/musb_regs.h

@@ -326,6 +326,26 @@ static inline void  musb_write_rxfifoadd(void __iomem *mbase, u16 c_off)
 	musb_writew(mbase, MUSB_RXFIFOADD, c_off);
 }
 
+static inline u8 musb_read_txfifosz(void __iomem *mbase)
+{
+	return musb_readb(mbase, MUSB_TXFIFOSZ);
+}
+
+static inline u16 musb_read_txfifoadd(void __iomem *mbase)
+{
+	return musb_readw(mbase, MUSB_TXFIFOADD);
+}
+
+static inline u8 musb_read_rxfifosz(void __iomem *mbase)
+{
+	return musb_readb(mbase, MUSB_RXFIFOSZ);
+}
+
+static inline u16  musb_read_rxfifoadd(void __iomem *mbase)
+{
+	return musb_readw(mbase, MUSB_RXFIFOADD);
+}
+
 static inline u8 musb_read_configdata(void __iomem *mbase)
 {
 	musb_writeb(mbase, MUSB_INDEX, 0);
@@ -381,6 +401,36 @@ static inline void  musb_write_txhubport(void __iomem *mbase, u8 epnum,
 			qh_h_port_reg);
 }
 
+static inline u8 musb_read_rxfunaddr(void __iomem *mbase, u8 epnum)
+{
+	return musb_readb(mbase, MUSB_BUSCTL_OFFSET(epnum, MUSB_RXFUNCADDR));
+}
+
+static inline u8 musb_read_rxhubaddr(void __iomem *mbase, u8 epnum)
+{
+	return musb_readb(mbase, MUSB_BUSCTL_OFFSET(epnum, MUSB_RXHUBADDR));
+}
+
+static inline u8 musb_read_rxhubport(void __iomem *mbase, u8 epnum)
+{
+	return musb_readb(mbase, MUSB_BUSCTL_OFFSET(epnum, MUSB_RXHUBPORT));
+}
+
+static inline u8  musb_read_txfunaddr(void __iomem *mbase, u8 epnum)
+{
+	return musb_readb(mbase, MUSB_BUSCTL_OFFSET(epnum, MUSB_TXFUNCADDR));
+}
+
+static inline u8  musb_read_txhubaddr(void __iomem *mbase, u8 epnum)
+{
+	return musb_readb(mbase, MUSB_BUSCTL_OFFSET(epnum, MUSB_TXHUBADDR));
+}
+
+static inline u8  musb_read_txhubport(void __iomem *mbase, u8 epnum)
+{
+	return musb_readb(mbase, MUSB_BUSCTL_OFFSET(epnum, MUSB_TXHUBPORT));
+}
+
 #else /* CONFIG_BLACKFIN */
 
 #define USB_BASE		USB_FADDR
@@ -460,6 +510,22 @@ static inline void  musb_write_rxfifoadd(void __iomem *mbase, u16 c_off)
 {
 }
 
+static inline u8 musb_read_txfifosz(void __iomem *mbase)
+{
+}
+
+static inline u16 musb_read_txfifoadd(void __iomem *mbase)
+{
+}
+
+static inline u8 musb_read_rxfifosz(void __iomem *mbase)
+{
+}
+
+static inline u16  musb_read_rxfifoadd(void __iomem *mbase)
+{
+}
+
 static inline u8 musb_read_configdata(void __iomem *mbase)
 {
 	return 0;
@@ -505,6 +571,30 @@ static inline void  musb_write_txhubport(void __iomem *mbase, u8 epnum,
 {
 }
 
+static inline u8 musb_read_rxfunaddr(void __iomem *mbase, u8 epnum)
+{
+}
+
+static inline u8 musb_read_rxhubaddr(void __iomem *mbase, u8 epnum)
+{
+}
+
+static inline u8 musb_read_rxhubport(void __iomem *mbase, u8 epnum)
+{
+}
+
+static inline u8  musb_read_txfunaddr(void __iomem *mbase, u8 epnum)
+{
+}
+
+static inline u8  musb_read_txhubaddr(void __iomem *mbase, u8 epnum)
+{
+}
+
+static inline void  musb_read_txhubport(void __iomem *mbase, u8 epnum)
+{
+}
+
 #endif /* CONFIG_BLACKFIN */
 
 #endif	/* __MUSB_REGS_H__ */