From 02286190f3ec86f03025a60c4d3f747ff1047248 Mon Sep 17 00:00:00 2001 From: Daniel Mack Date: Wed, 25 Jul 2012 15:28:35 +0200 Subject: [PATCH] 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 Acked-by: Timur Tabi Signed-off-by: Mark Brown --- Documentation/devicetree/bindings/sound/cs4270.txt | 5 +++++ sound/soc/codecs/cs4270.c | 17 +++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/Documentation/devicetree/bindings/sound/cs4270.txt b/Documentation/devicetree/bindings/sound/cs4270.txt index 7f0bfd8..6b222f9 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 4b71b01..fd11bb6 100644 --- a/sound/soc/codecs/cs4270.c +++ b/sound/soc/codecs/cs4270.c @@ -30,6 +30,7 @@ #include #include #include +#include /* * 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); -- 2.7.4