wl1251: make wl1251_set_partition bus agnostic

The same partition setting code can be used for both SPI and SDIO
modes, if we remove the spi-specific commands and use the more
generic buffer write routines.  Do that and move it to io.c
since it deals with register/memory address offsets.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/wl12xx/wl1251_io.c b/drivers/net/wireless/wl12xx/wl1251_io.c
index bc95785..db2cfbf 100644
--- a/drivers/net/wireless/wl12xx/wl1251_io.c
+++ b/drivers/net/wireless/wl12xx/wl1251_io.c
@@ -84,3 +84,98 @@
 {
 	wl1251_write32(wl, wl1251_translate_reg_addr(wl, addr), val);
 }
+
+/* Set the partitions to access the chip addresses.
+ *
+ * There are two VIRTUAL partitions (the memory partition and the
+ * registers partition), which are mapped to two different areas of the
+ * PHYSICAL (hardware) memory.  This function also makes other checks to
+ * ensure that the partitions are not overlapping.  In the diagram below, the
+ * memory partition comes before the register partition, but the opposite is
+ * also supported.
+ *
+ *                               PHYSICAL address
+ *                                     space
+ *
+ *                                    |    |
+ *                                 ...+----+--> mem_start
+ *          VIRTUAL address     ...   |    |
+ *               space       ...      |    | [PART_0]
+ *                        ...         |    |
+ * 0x00000000 <--+----+...         ...+----+--> mem_start + mem_size
+ *               |    |         ...   |    |
+ *               |MEM |      ...      |    |
+ *               |    |   ...         |    |
+ *  part_size <--+----+...            |    | {unused area)
+ *               |    |   ...         |    |
+ *               |REG |      ...      |    |
+ *  part_size    |    |         ...   |    |
+ *      +     <--+----+...         ...+----+--> reg_start
+ *  reg_size              ...         |    |
+ *                           ...      |    | [PART_1]
+ *                              ...   |    |
+ *                                 ...+----+--> reg_start + reg_size
+ *                                    |    |
+ *
+ */
+void wl1251_set_partition(struct wl1251 *wl,
+			  u32 mem_start, u32 mem_size,
+			  u32 reg_start, u32 reg_size)
+{
+	struct wl1251_partition partition[2];
+
+	wl1251_debug(DEBUG_SPI, "mem_start %08X mem_size %08X",
+		     mem_start, mem_size);
+	wl1251_debug(DEBUG_SPI, "reg_start %08X reg_size %08X",
+		     reg_start, reg_size);
+
+	/* Make sure that the two partitions together don't exceed the
+	 * address range */
+	if ((mem_size + reg_size) > HW_ACCESS_MEMORY_MAX_RANGE) {
+		wl1251_debug(DEBUG_SPI, "Total size exceeds maximum virtual"
+			     " address range.  Truncating partition[0].");
+		mem_size = HW_ACCESS_MEMORY_MAX_RANGE - reg_size;
+		wl1251_debug(DEBUG_SPI, "mem_start %08X mem_size %08X",
+			     mem_start, mem_size);
+		wl1251_debug(DEBUG_SPI, "reg_start %08X reg_size %08X",
+			     reg_start, reg_size);
+	}
+
+	if ((mem_start < reg_start) &&
+	    ((mem_start + mem_size) > reg_start)) {
+		/* Guarantee that the memory partition doesn't overlap the
+		 * registers partition */
+		wl1251_debug(DEBUG_SPI, "End of partition[0] is "
+			     "overlapping partition[1].  Adjusted.");
+		mem_size = reg_start - mem_start;
+		wl1251_debug(DEBUG_SPI, "mem_start %08X mem_size %08X",
+			     mem_start, mem_size);
+		wl1251_debug(DEBUG_SPI, "reg_start %08X reg_size %08X",
+			     reg_start, reg_size);
+	} else if ((reg_start < mem_start) &&
+		   ((reg_start + reg_size) > mem_start)) {
+		/* Guarantee that the register partition doesn't overlap the
+		 * memory partition */
+		wl1251_debug(DEBUG_SPI, "End of partition[1] is"
+			     " overlapping partition[0].  Adjusted.");
+		reg_size = mem_start - reg_start;
+		wl1251_debug(DEBUG_SPI, "mem_start %08X mem_size %08X",
+			     mem_start, mem_size);
+		wl1251_debug(DEBUG_SPI, "reg_start %08X reg_size %08X",
+			     reg_start, reg_size);
+	}
+
+	partition[0].start = mem_start;
+	partition[0].size  = mem_size;
+	partition[1].start = reg_start;
+	partition[1].size  = reg_size;
+
+	wl->physical_mem_addr = mem_start;
+	wl->physical_reg_addr = reg_start;
+
+	wl->virtual_mem_addr = 0;
+	wl->virtual_reg_addr = mem_size;
+
+	wl->if_ops->write(wl, HW_ACCESS_PART0_SIZE_ADDR, partition,
+		sizeof(partition));
+}