mmc: implement SDIO IO_RW_DIRECT operation

Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
diff --git a/include/linux/mmc/sdio.h b/include/linux/mmc/sdio.h
index d1a0b15..e5f06de 100644
--- a/include/linux/mmc/sdio.h
+++ b/include/linux/mmc/sdio.h
@@ -14,6 +14,40 @@
 
 /* SDIO commands                         type  argument     response */
 #define SD_IO_SEND_OP_COND          5 /* bcr  [23:0] OCR         R4  */
+#define SD_IO_RW_DIRECT            52 /* ac   [31:0] See below   R5  */
+
+/*
+ * SD_IO_RW_DIRECT argument format:
+ *
+ *      [31] R/W flag
+ *      [30:28] Function number
+ *      [27] RAW flag
+ *      [25:9] Register address
+ *      [7:0] Data
+ */
+
+/*
+  SDIO status in R5
+  Type
+	e : error bit
+	s : status bit
+	r : detected and set for the actual command response
+	x : detected and set during command execution. the host must poll
+            the card by sending status command in order to read these bits.
+  Clear condition
+	a : according to the card state
+	b : always related to the previous command. Reception of
+            a valid command will clear it (with a delay of one command)
+	c : clear by read
+ */
+
+#define R5_COM_CRC_ERROR	(1 << 15)	/* er, b */
+#define R5_ILLEGAL_COMMAND	(1 << 14)	/* er, b */
+#define R5_ERROR		(1 << 11)	/* erx, c */
+#define R5_FUNCTION_NUMBER	(1 << 9)	/* er, c */
+#define R5_OUT_OF_RANGE		(1 << 8)	/* er, c */
+#define R5_STATUS(x)		(x & 0xCB00)
+#define R5_IO_CURRENT_STATE(x)	((x & 0x3000) >> 12) /* s, b */
 
 #endif