ASoC: Add reset-gpio DT property to cs4270 driver

In the process of moving over from static board files to the device
tree, reset pins of peripheral reset pins should be handled by their
corresponding drivers.

Add a reset-gpio DT property to the cs4270 driver, and de-assert it
before probing the chip. The logic could be augmented some day to
re-assert it when codec is put to suspend.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/sound/cs4270.txt b/Documentation/devicetree/bindings/sound/cs4270.txt
index 7f0bfd84d3fc..6b222f9b8ef5 100644
--- a/Documentation/devicetree/bindings/sound/cs4270.txt
+++ b/Documentation/devicetree/bindings/sound/cs4270.txt
@@ -8,6 +8,11 @@ Required properties:
 
   - reg : the I2C address of the device for I2C
 
+Optional properties:
+
+  - reset-gpio : a GPIO spec for the reset pin. If specified, it will be
+                 deasserted before communication to the codec starts.
+
 Example:
 
 codec: cs4270@48 {