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authorDaniel Mack <zonque@gmail.com>2012-07-25 15:28:35 +0200
committerMark Brown <broonie@opensource.wolfsonmicro.com>2012-08-03 23:03:59 +0100
commit02286190f3ec86f03025a60c4d3f747ff1047248 (patch)
tree7cf1d705d24807b3c5bea0fd22d45ee8f7227475
parent85d07e4d625d6511934799f7df93e9111ac2c88b (diff)
downloadblackbird-op-linux-02286190f3ec86f03025a60c4d3f747ff1047248.tar.gz
blackbird-op-linux-02286190f3ec86f03025a60c4d3f747ff1047248.zip
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>
-rw-r--r--Documentation/devicetree/bindings/sound/cs4270.txt5
-rw-r--r--sound/soc/codecs/cs4270.c17
2 files changed, 22 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 {
diff --git a/sound/soc/codecs/cs4270.c b/sound/soc/codecs/cs4270.c
index 4b71b01ecbcd..fd11bb646d40 100644
--- a/sound/soc/codecs/cs4270.c
+++ b/sound/soc/codecs/cs4270.c
@@ -30,6 +30,7 @@
#include <linux/delay.h>
#include <linux/regulator/consumer.h>
#include <linux/of_device.h>
+#include <linux/of_gpio.h>
/*
* The codec isn't really big-endian or little-endian, since the I2S
@@ -660,9 +661,25 @@ MODULE_DEVICE_TABLE(of, cs4270_of_match);
static int cs4270_i2c_probe(struct i2c_client *i2c_client,
const struct i2c_device_id *id)
{
+ struct device_node *np = i2c_client->dev.of_node;
struct cs4270_private *cs4270;
int ret;
+ /* See if we have a way to bring the codec out of reset */
+ if (np) {
+ enum of_gpio_flags flags;
+ int gpio = of_get_named_gpio_flags(np, "reset-gpio", 0, &flags);
+
+ if (gpio_is_valid(gpio)) {
+ ret = devm_gpio_request_one(&i2c_client->dev, gpio,
+ flags & OF_GPIO_ACTIVE_LOW ?
+ GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH,
+ "cs4270 reset");
+ if (ret < 0)
+ return ret;
+ }
+ }
+
/* Verify that we have a CS4270 */
ret = i2c_smbus_read_byte_data(i2c_client, CS4270_CHIPID);
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