ALSA: hda - remove unnecessary controller dependency on i915 gfx power

index 52a85d8..b648928 100644
@@ -42,10 +42,15 @@ int hda_display_power(struct hda_intel *hda, bool enable)
 
 	dev_dbg(&hda->chip.pci->dev, "display power %s\n",
 		enable ? "enable" : "disable");
-	if (enable)
-		acomp->ops->get_power(acomp->dev);
-	else
-		acomp->ops->put_power(acomp->dev);
+
+	if (enable) {
+		if (!hda->i915_power_refcount++)
+			acomp->ops->get_power(acomp->dev);
+	} else {
+		WARN_ON(!hda->i915_power_refcount);
+		if (!--hda->i915_power_refcount)
+			acomp->ops->put_power(acomp->dev);
+	}
 
 	return 0;
 }

@@ -183,6 +188,11 @@ out_err:
 int hda_i915_exit(struct hda_intel *hda)
 {
 	struct device *dev = &hda->chip.pci->dev;
+	struct i915_audio_component *acomp = &hda->audio_component;
+
+	WARN_ON(hda->i915_power_refcount);
+	if (hda->i915_power_refcount > 0 && acomp->ops)
+		acomp->ops->put_power(acomp->dev);
 
 	component_master_del(dev, &hda_component_master_ops);
 

index 2069898..dc1d3ff 100644
@@ -46,6 +46,7 @@ struct hda_intel {
 
 	/* i915 component interface */
 	struct i915_audio_component audio_component;
+	int i915_power_refcount;
 };
 
 #ifdef CONFIG_SND_HDA_I915

index 6a2e030..b97c59e 100644
@@ -74,6 +74,7 @@ struct hdac_device {
 
 	/* misc flags */
 	atomic_t in_pm;		/* suspend/resume being performed */
+	bool  link_power_control:1;
 
 	/* sysfs */
 	struct hdac_widget_tree *widgets;

@@ -184,6 +185,8 @@ struct hdac_bus_ops {
 	/* get a response from the last command */
 	int (*get_response)(struct hdac_bus *bus, unsigned int addr,
 			    unsigned int *res);
+	/* control the link power  */
+	int (*link_power)(struct hdac_bus *bus, bool enable);
 };
 
 /*

@@ -311,6 +314,7 @@ static inline void snd_hdac_codec_link_down(struct hdac_device *codec)
 int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val);
 int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
 			      unsigned int *res);
+int snd_hdac_link_power(struct hdac_device *codec, bool enable);
 
 bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset);
 void snd_hdac_bus_stop_chip(struct hdac_bus *bus);

index 55c7d08..cdee710 100644
@@ -552,6 +552,21 @@ void snd_hdac_power_down_pm(struct hdac_device *codec)
 EXPORT_SYMBOL_GPL(snd_hdac_power_down_pm);
 #endif
 
+/*
+ * Enable/disable the link power for a codec.
+ */
+int snd_hdac_link_power(struct hdac_device *codec, bool enable)
+{
+	if  (!codec->link_power_control)
+		return 0;
+
+	if  (codec->bus->ops->link_power)
+		return codec->bus->ops->link_power(codec->bus, enable);
+	else
+		return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(snd_hdac_link_power);
+
 /* codec vendor labels */
 struct hda_vendor_id {
 	unsigned int id;

index 2d8883f..a85242f 100644
@@ -857,6 +857,7 @@ void snd_hda_codec_register(struct hda_codec *codec)
 		return;
 	if (device_is_registered(hda_codec_dev(codec))) {
 		snd_hda_register_beep_device(codec);
+		snd_hdac_link_power(&codec->core, true);
 		pm_runtime_enable(hda_codec_dev(codec));
 		/* it was powered up in snd_hda_codec_new(), now all done */
 		snd_hda_power_down(codec);

@@ -883,6 +884,7 @@ static int snd_hda_codec_dev_free(struct snd_device *device)
 	struct hda_codec *codec = device->device_data;
 
 	codec->in_freeing = 1;
+	snd_hdac_link_power(&codec->core, false);
 	snd_hdac_device_unregister(&codec->core);
 	put_device(hda_codec_dev(codec));
 	return 0;

@@ -3102,6 +3104,7 @@ static int hda_codec_runtime_suspend(struct device *dev)
 	if (codec_has_clkstop(codec) && codec_has_epss(codec) &&
 	    (state & AC_PWRST_CLK_STOP_OK))
 		snd_hdac_codec_link_down(&codec->core);
+	snd_hdac_link_power(&codec->core, false);
 	return 0;
 }
 

@@ -3109,6 +3112,7 @@ static int hda_codec_runtime_resume(struct device *dev)
 {
 	struct hda_codec *codec = dev_to_hda_codec(dev);
 
+	snd_hdac_link_power(&codec->core, true);
 	snd_hdac_codec_link_up(&codec->core);
 	hda_call_codec_resume(codec);
 	pm_runtime_mark_last_busy(dev);

index e0bb623..120854e 100644
@@ -775,9 +775,20 @@ static int azx_get_response(struct hdac_bus *bus, unsigned int addr,
 		return azx_rirb_get_response(bus, addr, res);
 }
 
+static int azx_link_power(struct hdac_bus *bus, bool enable)
+{
+	struct azx *chip = bus_to_azx(bus);
+
+	if (chip->ops->link_power)
+		return chip->ops->link_power(chip, enable);
+	else
+		return -EINVAL;
+}
+
 static const struct hdac_bus_ops bus_core_ops = {
 	.command = azx_send_cmd,
 	.get_response = azx_get_response,
+	.link_power = azx_link_power,
 };
 
 #ifdef CONFIG_SND_HDA_DSP_LOADER

index 173bf7c..3d26e61 100644
@@ -89,6 +89,8 @@ struct hda_controller_ops {
 				 struct vm_area_struct *area);
 	/* Check if current position is acceptable */
 	int (*position_check)(struct azx *chip, struct azx_dev *azx_dev);
+	/* enable/disable the link power */
+	int (*link_power)(struct azx *chip, bool enable);
 };
 
 struct azx_pcm {

index e615556..d70b405 100644
@@ -543,6 +543,14 @@ static int azx_position_check(struct azx *chip, struct azx_dev *azx_dev)
 	return 0;
 }
 
+/* Enable/disable i915 display power for the link */
+static int azx_intel_link_power(struct azx *chip, bool enable)
+{
+	struct hda_intel *hda = container_of(chip, struct hda_intel, chip);
+
+	return hda_display_power(hda, enable);
+}
+
 /*
  * Check whether the current DMA position is acceptable for updating
  * periods.  Returns non-zero if it's OK.

@@ -1789,6 +1797,7 @@ static const struct hda_controller_ops pci_hda_ops = {
 	.substream_free_pages = substream_free_pages,
 	.pcm_mmap_prepare = pcm_mmap_prepare,
 	.position_check = azx_position_check,
+	.link_power = azx_intel_link_power,
 };
 
 static int azx_probe(struct pci_dev *pci,

index d70b405..98e721b 100644
@@ -817,7 +817,8 @@ static int azx_suspend(struct device *dev)
 
 	if (chip->msi)
 		pci_disable_msi(chip->pci);
-	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
+	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
+		&& hda->need_i915_power)
 		hda_display_power(hda, false);
 	return 0;
 }

@@ -837,7 +838,8 @@ static int azx_resume(struct device *dev)
 	if (chip->disabled || hda->init_failed)
 		return 0;
 
-	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
+	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
+		&& hda->need_i915_power) {
 		hda_display_power(hda, true);
 		haswell_set_bclk(hda);
 	}

@@ -880,7 +882,8 @@ static int azx_runtime_suspend(struct device *dev)
 	azx_stop_chip(chip);
 	azx_enter_link_reset(chip);
 	azx_clear_irq_pending(chip);
-	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL)
+	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
+		&& hda->need_i915_power)
 		hda_display_power(hda, false);
 
 	return 0;

@@ -905,7 +908,8 @@ static int azx_runtime_resume(struct device *dev)
 	if (!azx_has_pm_runtime(chip))
 		return 0;
 
-	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
+	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
+		&& hda->need_i915_power) {
 		hda_display_power(hda, true);
 		haswell_set_bclk(hda);
 	}

@@ -1126,7 +1130,8 @@ static int azx_free(struct azx *chip)
 	release_firmware(chip->fw);
 #endif
 	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
-		hda_display_power(hda, false);
+		if (hda->need_i915_power)
+			hda_display_power(hda, false);
 		hda_i915_exit(hda);
 	}
 	kfree(hda);

@@ -1891,17 +1896,26 @@ static int azx_probe_continue(struct azx *chip)
 	int err;
 
 	hda->probe_continued = 1;
-	/* Request power well for Haswell HDA controller and codec */
+
+	/* Request display power well for the HDA controller or codec. For
+	 * Haswell/Broadwell, both the display HDA controller and codec need
+	 * this power. For other platforms, like Baytrail/Braswell, only the
+	 * display codec needs the power and it can be released after probe.
+	 */
 	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
+		/* Assume the controller needs the power by default */
+		hda->need_i915_power = 1;
+
 #ifdef CONFIG_SND_HDA_I915
 		err = hda_i915_init(hda);
 		if (err < 0)
-			goto out_free;
+			goto i915_power_fail;
+
 		err = hda_display_power(hda, true);
 		if (err < 0) {
 			dev_err(chip->card->dev,
 				"Cannot turn on display power on i915\n");
-			goto out_free;
+			goto i915_power_fail;
 		}
 #endif
 	}

@@ -1948,6 +1962,11 @@ static int azx_probe_continue(struct azx *chip)
 		pm_runtime_put_noidle(&pci->dev);
 
 out_free:
+	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL
+		&& !hda->need_i915_power)
+		hda_display_power(hda, false);
+
+i915_power_fail:
 	if (err < 0)
 		hda->init_failed = 1;
 	complete_all(&hda->probe_wait);

index dc1d3ff..505f987 100644
@@ -45,6 +45,7 @@ struct hda_intel {
 	struct dev_pm_domain hdmi_pm_domain;
 
 	/* i915 component interface */
+	bool need_i915_power:1; /* the hda controller needs i915 power */
 	struct i915_audio_component audio_component;
 	int i915_power_refcount;
 };

index 98e721b..f8b574b 100644
@@ -1903,8 +1903,10 @@ static int azx_probe_continue(struct azx *chip)
 	 * display codec needs the power and it can be released after probe.
 	 */
 	if (chip->driver_caps & AZX_DCAPS_I915_POWERWELL) {
-		/* Assume the controller needs the power by default */
-		hda->need_i915_power = 1;
+		/* Baytral/Braswell controllers don't need this power */
+		if (pci->device != 0x0f04 && pci->device != 0x2284)
+			hda->need_i915_power = 1;
+
 
 #ifdef CONFIG_SND_HDA_I915
 		err = hda_i915_init(hda);

index 5f44f60..a8016e1 100644
@@ -2335,6 +2335,15 @@ static int patch_generic_hdmi(struct hda_codec *codec)
 		intel_haswell_fixup_enable_dp12(codec);
 	}
 
+	/* For Valleyview/Cherryview, only the display codec is in the display
+	 * power well and can use link_power ops to request/release the power.
+	 * For Haswell/Broadwell, the controller is also in the power well and
+	 * can cover the codec power request, and so need not set this flag.
+	 * For previous platforms, there is no such power well feature.
+	 */
+	if (is_valleyview_plus(codec))
+		codec->core.link_power_control = 1;
+
 	if (is_haswell_plus(codec) || is_valleyview_plus(codec))
 		codec->depop_delay = 0;