mfd: Don't store volatile bits in WM8350 register cache

This makes the contents of the cache clearer and fixes incorrect
initialisation of the cache for partially volatile registers.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>

drivers/mfd/wm8350-core.c

@@ -183,6 +183,9 @@ static int wm8350_write(struct wm8350 *wm8350, u8 reg, int num_regs, u16 *src)
 			(wm8350->reg_cache[i] & ~wm8350_reg_io_map[i].writable)
 			| src[i - reg];
 
+		/* Don't store volatile bits */
+		wm8350->reg_cache[i] &= ~wm8350_reg_io_map[i].vol;
+
 		src[i - reg] = cpu_to_be16(src[i - reg]);
 	}
 
@@ -1120,6 +1123,7 @@ static int wm8350_create_cache(struct wm8350 *wm8350, int mode)
 			}
 			value = be16_to_cpu(value);
 			value &= wm8350_reg_io_map[i].readable;
+			value &= ~wm8350_reg_io_map[i].vol;
 			wm8350->reg_cache[i] = value;
 		} else
 			wm8350->reg_cache[i] = reg_map[i];