[PATCH 1/4] ASoC: sun4i-codec: Add support for PA gpio pin

[Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

Add support for PA gpio pin for controlling an external amplifier as used
on some Allwinner boards.

Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 .../devicetree/bindings/sound/sun4i-codec.txt      |  3 +++
 sound/soc/sunxi/sun4i-codec.c                      | 25 ++++++++++++++--------
 2 files changed, 19 insertions(+), 9 deletions(-)

diff --git a/Documentation/devicetree/bindings/sound/sun4i-codec.txt b/Documentation/devicetree/bindings/sound/sun4i-codec.txt
index c92966b..974babe 100644
--- a/Documentation/devicetree/bindings/sound/sun4i-codec.txt
+++ b/Documentation/devicetree/bindings/sound/sun4i-codec.txt
@@ -14,6 +14,9 @@ Required properties:
    - "apb": the parent APB clock for this controller
    - "codec": the parent module clock
 
+Optional properties:
+- pa-gpios: gpio to enable external amplifier
+
 Example:
 codec: codec@01c22c00 {
 	#sound-dai-cells = <0>;
diff --git a/sound/soc/sunxi/sun4i-codec.c b/sound/soc/sunxi/sun4i-codec.c
index bcbf4da..2aca9cd 100644
--- a/sound/soc/sunxi/sun4i-codec.c
+++ b/sound/soc/sunxi/sun4i-codec.c
@@ -27,6 +27,7 @@
 #include <linux/of_address.h>
 #include <linux/clk.h>
 #include <linux/regmap.h>
+#include <linux/gpio/consumer.h>
 
 #include <sound/core.h>
 #include <sound/pcm.h>
@@ -101,16 +102,15 @@ struct sun4i_codec {
 	struct regmap	*regmap;
 	struct clk	*clk_apb;
 	struct clk	*clk_module;
+	struct gpio_desc *gpio_pa;
 
 	struct snd_dmaengine_dai_dma_data	playback_dma_data;
 };
 
 static void sun4i_codec_start_playback(struct sun4i_codec *scodec)
 {
-	/*
-	 * FIXME: according to the BSP, we might need to drive a PA
-	 *        GPIO high here on some boards
-	 */
+	if (scodec->gpio_pa)
+		gpiod_set_value_cansleep(scodec->gpio_pa, 1);
 
 	/* Flush TX FIFO */
 	regmap_update_bits(scodec->regmap, SUN4I_CODEC_DAC_FIFOC,
@@ -125,15 +125,13 @@ static void sun4i_codec_start_playback(struct sun4i_codec *scodec)
 
 static void sun4i_codec_stop_playback(struct sun4i_codec *scodec)
 {
-	/*
-	 * FIXME: according to the BSP, we might need to drive a PA
-	 *        GPIO low here on some boards
-	 */
-
 	/* Disable DAC DRQ */
 	regmap_update_bits(scodec->regmap, SUN4I_CODEC_DAC_FIFOC,
 			   BIT(SUN4I_CODEC_DAC_FIFOC_DAC_DRQ_EN),
 			   0);
+
+	if (scodec->gpio_pa)
+		gpiod_set_value_cansleep(scodec->gpio_pa, 0);
 }
 
 static int sun4i_codec_trigger(struct snd_pcm_substream *substream, int cmd,
@@ -633,6 +631,15 @@ static int sun4i_codec_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
+	scodec->gpio_pa = devm_gpiod_get_optional(&pdev->dev, "pa",
+						  GPIOD_OUT_HIGH);
+	if (IS_ERR(scodec->gpio_pa)) {
+		ret = PTR_ERR(scodec->gpio_pa);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to get pa gpio: %d\n", ret);
+		return ret;
+	}
+
 	/* DMA configuration for TX FIFO */
 	scodec->playback_dma_data.addr = res->start + SUN4I_CODEC_DAC_TXDATA;
 	scodec->playback_dma_data.maxburst = 4;
-- 
2.5.0