powerpc/5200: add LocalPlus bus FIFO device driver

This is a driver for the FIFO device on the LocalPlus bus on an mpc5200 system.
The driver supports programmed I/O through the FIFO as well as setting up DMA
via the BestComm engine through the FIFO.

Signed-off-by: John Bonesio <bones@secretlab.ca>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

arch/powerpc/include/asm/mpc52xx.h

@@ -283,6 +283,45 @@ extern int mpc52xx_gpt_start_timer(struct mpc52xx_gpt_priv *gpt, int period,
                             int continuous);
 extern void mpc52xx_gpt_stop_timer(struct mpc52xx_gpt_priv *gpt);
 
+/* mpc52xx_lpbfifo.c */
+#define MPC52XX_LPBFIFO_FLAG_READ		(0)
+#define MPC52XX_LPBFIFO_FLAG_WRITE		(1<<0)
+#define MPC52XX_LPBFIFO_FLAG_NO_INCREMENT	(1<<1)
+#define MPC52XX_LPBFIFO_FLAG_NO_DMA		(1<<2)
+#define MPC52XX_LPBFIFO_FLAG_POLL_DMA		(1<<3)
+
+struct mpc52xx_lpbfifo_request {
+	struct list_head list;
+
+	/* localplus bus address */
+	unsigned int cs;
+	size_t offset;
+
+	/* Memory address */
+	void *data;
+	phys_addr_t data_phys;
+
+	/* Details of transfer */
+	size_t size;
+	size_t pos;	/* current position of transfer */
+	int flags;
+
+	/* What to do when finished */
+	void (*callback)(struct mpc52xx_lpbfifo_request *);
+
+	void *priv;		/* Driver private data */
+
+	/* statistics */
+	int irq_count;
+	int irq_ticks;
+	u8 last_byte;
+	int buffer_not_done_cnt;
+};
+
+extern int mpc52xx_lpbfifo_submit(struct mpc52xx_lpbfifo_request *req);
+extern void mpc52xx_lpbfifo_abort(struct mpc52xx_lpbfifo_request *req);
+extern void mpc52xx_lpbfifo_poll(void);
+
 /* mpc52xx_pic.c */
 extern void mpc52xx_init_irq(void);
 extern unsigned int mpc52xx_get_irq(void);