ASoC: SOF: Intel: Initialize hdaudio bus properly

The SOF HD-audio bus has its house-made initialization code.  It's
supposedly for making the code independent from HD-audio bus drivers.
However, this is error-prone, and above all, the SOF driver has
already dependency on HD-audio bus driver when CONFIG_SND_SOF_HDA is
set.  That is, if this Kconfig is set, there is no reason to avoid the
call to the proper bus init function.

Also, the ext_ops that is set at bus initialization can be better
handled inside sof_hda_bus_init().  We don't need to refer this
outside the bus initialization.

So this patch addresses these issues:
- sof_hda_bus_init() calls nothing but snd_hdac_ext_bus_init()
  when CONFIG_SND_SOF_HDA is set.  Otherwise some fields are
  initialized locally like before for avoiding the dependency.
- ext_ops is referred inside sof_hda_bus_init().  The ext_ops argument
  of snd_hda_bus_init() is dropped.
Acked-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/soc/sof/intel/hda-bus.c

@@ -12,28 +12,26 @@
 #include "../sof-priv.h"
 #include "hda.h"
 
-#if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA)
-
-static const struct hdac_bus_ops bus_ops = {
-	.command = snd_hdac_bus_send_cmd,
-	.get_response = snd_hdac_bus_get_response,
-};
-
+#if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_AUDIO_CODEC)
+#define sof_hda_ext_ops	snd_soc_hdac_hda_get_ops()
+#else
+#define sof_hda_ext_ops	NULL
 #endif
 
 /*
  * This can be used for both with/without hda link support.
  */
-void sof_hda_bus_init(struct hdac_bus *bus, struct device *dev,
-		      const struct hdac_ext_bus_ops *ext_ops)
+void sof_hda_bus_init(struct hdac_bus *bus, struct device *dev)
 {
+#if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA)
+	snd_hdac_ext_bus_init(bus, dev, NULL, sof_hda_ext_ops);
+#else /* CONFIG_SND_SOC_SOF_HDA */
 	memset(bus, 0, sizeof(*bus));
 	bus->dev = dev;
 
 	INIT_LIST_HEAD(&bus->stream_list);
 
 	bus->irq = -1;
-	bus->ext_ops = ext_ops;
 
 	/*
 	 * There is only one HDA bus atm. keep the index as 0.
@@ -42,16 +40,5 @@ void sof_hda_bus_init(struct hdac_bus *bus, struct device *dev,
 	bus->idx = 0;
 
 	spin_lock_init(&bus->reg_lock);
-
-#if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA)
-	INIT_LIST_HEAD(&bus->codec_list);
-	INIT_LIST_HEAD(&bus->hlink_list);
-
-	mutex_init(&bus->cmd_mutex);
-	mutex_init(&bus->lock);
-	bus->ops = &bus_ops;
-	INIT_WORK(&bus->unsol_work, snd_hdac_bus_process_unsol_events);
-	bus->cmd_dma_state = true;
-#endif
-
+#endif /* CONFIG_SND_SOC_SOF_HDA */
 }

sound/soc/sof/intel/hda.c

@@ -236,7 +236,6 @@ static int hda_init(struct snd_sof_dev *sdev)
 {
 	struct hda_bus *hbus;
 	struct hdac_bus *bus;
-	struct hdac_ext_bus_ops *ext_ops = NULL;
 	struct pci_dev *pci = to_pci_dev(sdev->dev);
 	int ret;
 
@@ -244,10 +243,7 @@ static int hda_init(struct snd_sof_dev *sdev)
 	bus = sof_to_bus(sdev);
 
 	/* HDA bus init */
-#if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_AUDIO_CODEC)
-	ext_ops = snd_soc_hdac_hda_get_ops();
-#endif
-	sof_hda_bus_init(bus, &pci->dev, ext_ops);
+	sof_hda_bus_init(bus, &pci->dev);
 
 	/* Workaround for a communication error on CFL (bko#199007) and CNL */
 	if (IS_CFL(pci) || IS_CNL(pci))

sound/soc/sof/intel/hda.h

@@ -549,8 +549,7 @@ void hda_dsp_ctrl_stop_chip(struct snd_sof_dev *sdev);
 /*
  * HDA bus operations.
  */
-void sof_hda_bus_init(struct hdac_bus *bus, struct device *dev,
-		      const struct hdac_ext_bus_ops *ext_ops);
+void sof_hda_bus_init(struct hdac_bus *bus, struct device *dev);
 
 #if IS_ENABLED(CONFIG_SND_SOC_SOF_HDA)
 /*