[alsa-devel] [PATCH 03/12] ASoC: intel: bxt_da7219_max98357a: add device_link to HDMI audio

[libin.yang at intel.com]

From: Libin Yang <libin.yang at intel.com>

In resume from S3, HDAC HDMI codec driver dapm event callback may be
operated before HDMI codec driver turns on the display audio power
domain because of the contest between display driver and hdmi codec driver.

This patch adds the device_link between bxt_da7219_max98357a machine device
(consumer) and hdmi codec device (supplier) to make sure the sequence is
always correct.

Signed-off-by: Libin Yang <libin.yang at intel.com>
---
 sound/soc/intel/boards/bxt_da7219_max98357a.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/sound/soc/intel/boards/bxt_da7219_max98357a.c b/sound/soc/intel/boards/bxt_da7219_max98357a.c
index 5cadb7f..9a0ec2c 100644
--- a/sound/soc/intel/boards/bxt_da7219_max98357a.c
+++ b/sound/soc/intel/boards/bxt_da7219_max98357a.c
@@ -29,6 +29,7 @@
 #include "../../codecs/hdac_hdmi.h"
 #include "../../codecs/da7219.h"
 #include "../../codecs/da7219-aad.h"
+#include "hdac_hdmi_common.h"
 
 #define BXT_DIALOG_CODEC_DAI	"da7219-hifi"
 #define BXT_MAXIM_CODEC_DAI	"HiFi"
@@ -46,6 +47,7 @@ struct bxt_hdmi_pcm {
 
 struct bxt_card_private {
 	struct list_head hdmi_pcm_list;
+	struct device_link *link;
 };
 
 enum {
@@ -237,7 +239,8 @@ static int broxton_hdmi_init(struct snd_soc_pcm_runtime *rtd)
 
 	list_add_tail(&pcm->head, &ctx->hdmi_pcm_list);
 
-	return 0;
+	/* Setup a device_link between machine device and HDMI codec device. */
+	return hdac_hdmi_add_device_link(rtd->card->dev, dai->dev, &ctx->link);
 }
 
 static int broxton_da7219_fe_init(struct snd_soc_pcm_runtime *rtd)
@@ -684,8 +687,17 @@ static const struct platform_device_id bxt_board_ids[] = {
 	{ }
 };
 
+static int broxton_audio_remove(struct platform_device *pdev)
+{
+	struct snd_soc_card *card = platform_get_drvdata(pdev);
+	struct bxt_card_private *ctx = snd_soc_card_get_drvdata(card);
+
+	return hdac_hdmi_del_device_link(&ctx->link);
+}
+
 static struct platform_driver broxton_audio = {
 	.probe = broxton_audio_probe,
+	.remove = broxton_audio_remove,
 	.driver = {
 		.name = "bxt_da7219_max98357a",
 		.pm = &snd_soc_pm_ops,
-- 
2.7.4