MFD: twl6040: Add accessor for revision ID

For client driver to use, if they need chip resvision information.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Acked-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/include/linux/mfd/twl6040.h b/include/linux/mfd/twl6040.h
index 4c806f6..cb3b822 100644
--- a/include/linux/mfd/twl6040.h
+++ b/include/linux/mfd/twl6040.h
@@ -225,4 +225,9 @@
 int twl6040_irq_init(struct twl6040 *twl6040);
 void twl6040_irq_exit(struct twl6040 *twl6040);
 
+static inline int twl6040_get_revid(struct twl6040 *twl6040)
+{
+	return twl6040->rev;
+}
+
 #endif  /* End of __TWL6040_CODEC_H__ */