Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 573 insertions, 0 deletions

diff --git a/kernel/drivers/gpu/drm/i915/intel_audio.c b/kernel/drivers/gpu/drm/i915/intel_audio.c
new file mode 100644
index 000000000..2396cc702
--- /dev/null
+++ b/kernel/drivers/gpu/drm/i915/intel_audio.c
@@ -0,0 +1,573 @@
+/*
+ * Copyright © 2014 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/component.h>
+#include <drm/i915_component.h>
+#include "intel_drv.h"
+
+#include <drm/drmP.h>
+#include <drm/drm_edid.h>
+#include "intel_drv.h"
+#include "i915_drv.h"
+
+/**
+ * DOC: High Definition Audio over HDMI and Display Port
+ *
+ * The graphics and audio drivers together support High Definition Audio over
+ * HDMI and Display Port. The audio programming sequences are divided into audio
+ * codec and controller enable and disable sequences. The graphics driver
+ * handles the audio codec sequences, while the audio driver handles the audio
+ * controller sequences.
+ *
+ * The disable sequences must be performed before disabling the transcoder or
+ * port. The enable sequences may only be performed after enabling the
+ * transcoder and port, and after completed link training.
+ *
+ * The codec and controller sequences could be done either parallel or serial,
+ * but generally the ELDV/PD change in the codec sequence indicates to the audio
+ * driver that the controller sequence should start. Indeed, most of the
+ * co-operation between the graphics and audio drivers is handled via audio
+ * related registers. (The notable exception is the power management, not
+ * covered here.)
+ */
+
+static const struct {
+	int clock;
+	u32 config;
+} hdmi_audio_clock[] = {
+	{ DIV_ROUND_UP(25200 * 1000, 1001), AUD_CONFIG_PIXEL_CLOCK_HDMI_25175 },
+	{ 25200, AUD_CONFIG_PIXEL_CLOCK_HDMI_25200 }, /* default per bspec */
+	{ 27000, AUD_CONFIG_PIXEL_CLOCK_HDMI_27000 },
+	{ 27000 * 1001 / 1000, AUD_CONFIG_PIXEL_CLOCK_HDMI_27027 },
+	{ 54000, AUD_CONFIG_PIXEL_CLOCK_HDMI_54000 },
+	{ 54000 * 1001 / 1000, AUD_CONFIG_PIXEL_CLOCK_HDMI_54054 },
+	{ DIV_ROUND_UP(74250 * 1000, 1001), AUD_CONFIG_PIXEL_CLOCK_HDMI_74176 },
+	{ 74250, AUD_CONFIG_PIXEL_CLOCK_HDMI_74250 },
+	{ DIV_ROUND_UP(148500 * 1000, 1001), AUD_CONFIG_PIXEL_CLOCK_HDMI_148352 },
+	{ 148500, AUD_CONFIG_PIXEL_CLOCK_HDMI_148500 },
+};
+
+/* get AUD_CONFIG_PIXEL_CLOCK_HDMI_* value for mode */
+static u32 audio_config_hdmi_pixel_clock(struct drm_display_mode *mode)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hdmi_audio_clock); i++) {
+		if (mode->clock == hdmi_audio_clock[i].clock)
+			break;
+	}
+
+	if (i == ARRAY_SIZE(hdmi_audio_clock)) {
+		DRM_DEBUG_KMS("HDMI audio pixel clock setting for %d not found, falling back to defaults\n", mode->clock);
+		i = 1;
+	}
+
+	DRM_DEBUG_KMS("Configuring HDMI audio for pixel clock %d (0x%08x)\n",
+		      hdmi_audio_clock[i].clock,
+		      hdmi_audio_clock[i].config);
+
+	return hdmi_audio_clock[i].config;
+}
+
+static bool intel_eld_uptodate(struct drm_connector *connector,
+			       int reg_eldv, uint32_t bits_eldv,
+			       int reg_elda, uint32_t bits_elda,
+			       int reg_edid)
+{
+	struct drm_i915_private *dev_priv = connector->dev->dev_private;
+	uint8_t *eld = connector->eld;
+	uint32_t tmp;
+	int i;
+
+	tmp = I915_READ(reg_eldv);
+	tmp &= bits_eldv;
+
+	if (!tmp)
+		return false;
+
+	tmp = I915_READ(reg_elda);
+	tmp &= ~bits_elda;
+	I915_WRITE(reg_elda, tmp);
+
+	for (i = 0; i < drm_eld_size(eld) / 4; i++)
+		if (I915_READ(reg_edid) != *((uint32_t *)eld + i))
+			return false;
+
+	return true;
+}
+
+static void g4x_audio_codec_disable(struct intel_encoder *encoder)
+{
+	struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+	uint32_t eldv, tmp;
+
+	DRM_DEBUG_KMS("Disable audio codec\n");
+
+	tmp = I915_READ(G4X_AUD_VID_DID);
+	if (tmp == INTEL_AUDIO_DEVBLC || tmp == INTEL_AUDIO_DEVCL)
+		eldv = G4X_ELDV_DEVCL_DEVBLC;
+	else
+		eldv = G4X_ELDV_DEVCTG;
+
+	/* Invalidate ELD */
+	tmp = I915_READ(G4X_AUD_CNTL_ST);
+	tmp &= ~eldv;
+	I915_WRITE(G4X_AUD_CNTL_ST, tmp);
+}
+
+static void g4x_audio_codec_enable(struct drm_connector *connector,
+				   struct intel_encoder *encoder,
+				   struct drm_display_mode *mode)
+{
+	struct drm_i915_private *dev_priv = connector->dev->dev_private;
+	uint8_t *eld = connector->eld;
+	uint32_t eldv;
+	uint32_t tmp;
+	int len, i;
+
+	DRM_DEBUG_KMS("Enable audio codec, %u bytes ELD\n", eld[2]);
+
+	tmp = I915_READ(G4X_AUD_VID_DID);
+	if (tmp == INTEL_AUDIO_DEVBLC || tmp == INTEL_AUDIO_DEVCL)
+		eldv = G4X_ELDV_DEVCL_DEVBLC;
+	else
+		eldv = G4X_ELDV_DEVCTG;
+
+	if (intel_eld_uptodate(connector,
+			       G4X_AUD_CNTL_ST, eldv,
+			       G4X_AUD_CNTL_ST, G4X_ELD_ADDR_MASK,
+			       G4X_HDMIW_HDMIEDID))
+		return;
+
+	tmp = I915_READ(G4X_AUD_CNTL_ST);
+	tmp &= ~(eldv | G4X_ELD_ADDR_MASK);
+	len = (tmp >> 9) & 0x1f;		/* ELD buffer size */
+	I915_WRITE(G4X_AUD_CNTL_ST, tmp);
+
+	len = min(drm_eld_size(eld) / 4, len);
+	DRM_DEBUG_DRIVER("ELD size %d\n", len);
+	for (i = 0; i < len; i++)
+		I915_WRITE(G4X_HDMIW_HDMIEDID, *((uint32_t *)eld + i));
+
+	tmp = I915_READ(G4X_AUD_CNTL_ST);
+	tmp |= eldv;
+	I915_WRITE(G4X_AUD_CNTL_ST, tmp);
+}
+
+static void hsw_audio_codec_disable(struct intel_encoder *encoder)
+{
+	struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+	enum pipe pipe = intel_crtc->pipe;
+	uint32_t tmp;
+
+	DRM_DEBUG_KMS("Disable audio codec on pipe %c\n", pipe_name(pipe));
+
+	/* Disable timestamps */
+	tmp = I915_READ(HSW_AUD_CFG(pipe));
+	tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
+	tmp |= AUD_CONFIG_N_PROG_ENABLE;
+	tmp &= ~AUD_CONFIG_UPPER_N_MASK;
+	tmp &= ~AUD_CONFIG_LOWER_N_MASK;
+	if (intel_pipe_has_type(intel_crtc, INTEL_OUTPUT_DISPLAYPORT))
+		tmp |= AUD_CONFIG_N_VALUE_INDEX;
+	I915_WRITE(HSW_AUD_CFG(pipe), tmp);
+
+	/* Invalidate ELD */
+	tmp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
+	tmp &= ~AUDIO_ELD_VALID(pipe);
+	tmp &= ~AUDIO_OUTPUT_ENABLE(pipe);
+	I915_WRITE(HSW_AUD_PIN_ELD_CP_VLD, tmp);
+}
+
+static void hsw_audio_codec_enable(struct drm_connector *connector,
+				   struct intel_encoder *encoder,
+				   struct drm_display_mode *mode)
+{
+	struct drm_i915_private *dev_priv = connector->dev->dev_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+	enum pipe pipe = intel_crtc->pipe;
+	const uint8_t *eld = connector->eld;
+	uint32_t tmp;
+	int len, i;
+
+	DRM_DEBUG_KMS("Enable audio codec on pipe %c, %u bytes ELD\n",
+		      pipe_name(pipe), drm_eld_size(eld));
+
+	/* Enable audio presence detect, invalidate ELD */
+	tmp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
+	tmp |= AUDIO_OUTPUT_ENABLE(pipe);
+	tmp &= ~AUDIO_ELD_VALID(pipe);
+	I915_WRITE(HSW_AUD_PIN_ELD_CP_VLD, tmp);
+
+	/*
+	 * FIXME: We're supposed to wait for vblank here, but we have vblanks
+	 * disabled during the mode set. The proper fix would be to push the
+	 * rest of the setup into a vblank work item, queued here, but the
+	 * infrastructure is not there yet.
+	 */
+
+	/* Reset ELD write address */
+	tmp = I915_READ(HSW_AUD_DIP_ELD_CTRL(pipe));
+	tmp &= ~IBX_ELD_ADDRESS_MASK;
+	I915_WRITE(HSW_AUD_DIP_ELD_CTRL(pipe), tmp);
+
+	/* Up to 84 bytes of hw ELD buffer */
+	len = min(drm_eld_size(eld), 84);
+	for (i = 0; i < len / 4; i++)
+		I915_WRITE(HSW_AUD_EDID_DATA(pipe), *((uint32_t *)eld + i));
+
+	/* ELD valid */
+	tmp = I915_READ(HSW_AUD_PIN_ELD_CP_VLD);
+	tmp |= AUDIO_ELD_VALID(pipe);
+	I915_WRITE(HSW_AUD_PIN_ELD_CP_VLD, tmp);
+
+	/* Enable timestamps */
+	tmp = I915_READ(HSW_AUD_CFG(pipe));
+	tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
+	tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
+	tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK;
+	if (intel_pipe_has_type(intel_crtc, INTEL_OUTPUT_DISPLAYPORT))
+		tmp |= AUD_CONFIG_N_VALUE_INDEX;
+	else
+		tmp |= audio_config_hdmi_pixel_clock(mode);
+	I915_WRITE(HSW_AUD_CFG(pipe), tmp);
+}
+
+static void ilk_audio_codec_disable(struct intel_encoder *encoder)
+{
+	struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+	struct intel_digital_port *intel_dig_port =
+		enc_to_dig_port(&encoder->base);
+	enum port port = intel_dig_port->port;
+	enum pipe pipe = intel_crtc->pipe;
+	uint32_t tmp, eldv;
+	int aud_config;
+	int aud_cntrl_st2;
+
+	DRM_DEBUG_KMS("Disable audio codec on port %c, pipe %c\n",
+		      port_name(port), pipe_name(pipe));
+
+	if (HAS_PCH_IBX(dev_priv->dev)) {
+		aud_config = IBX_AUD_CFG(pipe);
+		aud_cntrl_st2 = IBX_AUD_CNTL_ST2;
+	} else if (IS_VALLEYVIEW(dev_priv)) {
+		aud_config = VLV_AUD_CFG(pipe);
+		aud_cntrl_st2 = VLV_AUD_CNTL_ST2;
+	} else {
+		aud_config = CPT_AUD_CFG(pipe);
+		aud_cntrl_st2 = CPT_AUD_CNTRL_ST2;
+	}
+
+	/* Disable timestamps */
+	tmp = I915_READ(aud_config);
+	tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
+	tmp |= AUD_CONFIG_N_PROG_ENABLE;
+	tmp &= ~AUD_CONFIG_UPPER_N_MASK;
+	tmp &= ~AUD_CONFIG_LOWER_N_MASK;
+	if (intel_pipe_has_type(intel_crtc, INTEL_OUTPUT_DISPLAYPORT))
+		tmp |= AUD_CONFIG_N_VALUE_INDEX;
+	I915_WRITE(aud_config, tmp);
+
+	if (WARN_ON(!port)) {
+		eldv = IBX_ELD_VALID(PORT_B) | IBX_ELD_VALID(PORT_C) |
+			IBX_ELD_VALID(PORT_D);
+	} else {
+		eldv = IBX_ELD_VALID(port);
+	}
+
+	/* Invalidate ELD */
+	tmp = I915_READ(aud_cntrl_st2);
+	tmp &= ~eldv;
+	I915_WRITE(aud_cntrl_st2, tmp);
+}
+
+static void ilk_audio_codec_enable(struct drm_connector *connector,
+				   struct intel_encoder *encoder,
+				   struct drm_display_mode *mode)
+{
+	struct drm_i915_private *dev_priv = connector->dev->dev_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+	struct intel_digital_port *intel_dig_port =
+		enc_to_dig_port(&encoder->base);
+	enum port port = intel_dig_port->port;
+	enum pipe pipe = intel_crtc->pipe;
+	uint8_t *eld = connector->eld;
+	uint32_t eldv;
+	uint32_t tmp;
+	int len, i;
+	int hdmiw_hdmiedid;
+	int aud_config;
+	int aud_cntl_st;
+	int aud_cntrl_st2;
+
+	DRM_DEBUG_KMS("Enable audio codec on port %c, pipe %c, %u bytes ELD\n",
+		      port_name(port), pipe_name(pipe), drm_eld_size(eld));
+
+	/*
+	 * FIXME: We're supposed to wait for vblank here, but we have vblanks
+	 * disabled during the mode set. The proper fix would be to push the
+	 * rest of the setup into a vblank work item, queued here, but the
+	 * infrastructure is not there yet.
+	 */
+
+	if (HAS_PCH_IBX(connector->dev)) {
+		hdmiw_hdmiedid = IBX_HDMIW_HDMIEDID(pipe);
+		aud_config = IBX_AUD_CFG(pipe);
+		aud_cntl_st = IBX_AUD_CNTL_ST(pipe);
+		aud_cntrl_st2 = IBX_AUD_CNTL_ST2;
+	} else if (IS_VALLEYVIEW(connector->dev)) {
+		hdmiw_hdmiedid = VLV_HDMIW_HDMIEDID(pipe);
+		aud_config = VLV_AUD_CFG(pipe);
+		aud_cntl_st = VLV_AUD_CNTL_ST(pipe);
+		aud_cntrl_st2 = VLV_AUD_CNTL_ST2;
+	} else {
+		hdmiw_hdmiedid = CPT_HDMIW_HDMIEDID(pipe);
+		aud_config = CPT_AUD_CFG(pipe);
+		aud_cntl_st = CPT_AUD_CNTL_ST(pipe);
+		aud_cntrl_st2 = CPT_AUD_CNTRL_ST2;
+	}
+
+	if (WARN_ON(!port)) {
+		eldv = IBX_ELD_VALID(PORT_B) | IBX_ELD_VALID(PORT_C) |
+			IBX_ELD_VALID(PORT_D);
+	} else {
+		eldv = IBX_ELD_VALID(port);
+	}
+
+	/* Invalidate ELD */
+	tmp = I915_READ(aud_cntrl_st2);
+	tmp &= ~eldv;
+	I915_WRITE(aud_cntrl_st2, tmp);
+
+	/* Reset ELD write address */
+	tmp = I915_READ(aud_cntl_st);
+	tmp &= ~IBX_ELD_ADDRESS_MASK;
+	I915_WRITE(aud_cntl_st, tmp);
+
+	/* Up to 84 bytes of hw ELD buffer */
+	len = min(drm_eld_size(eld), 84);
+	for (i = 0; i < len / 4; i++)
+		I915_WRITE(hdmiw_hdmiedid, *((uint32_t *)eld + i));
+
+	/* ELD valid */
+	tmp = I915_READ(aud_cntrl_st2);
+	tmp |= eldv;
+	I915_WRITE(aud_cntrl_st2, tmp);
+
+	/* Enable timestamps */
+	tmp = I915_READ(aud_config);
+	tmp &= ~AUD_CONFIG_N_VALUE_INDEX;
+	tmp &= ~AUD_CONFIG_N_PROG_ENABLE;
+	tmp &= ~AUD_CONFIG_PIXEL_CLOCK_HDMI_MASK;
+	if (intel_pipe_has_type(intel_crtc, INTEL_OUTPUT_DISPLAYPORT))
+		tmp |= AUD_CONFIG_N_VALUE_INDEX;
+	else
+		tmp |= audio_config_hdmi_pixel_clock(mode);
+	I915_WRITE(aud_config, tmp);
+}
+
+/**
+ * intel_audio_codec_enable - Enable the audio codec for HD audio
+ * @intel_encoder: encoder on which to enable audio
+ *
+ * The enable sequences may only be performed after enabling the transcoder and
+ * port, and after completed link training.
+ */
+void intel_audio_codec_enable(struct intel_encoder *intel_encoder)
+{
+	struct drm_encoder *encoder = &intel_encoder->base;
+	struct intel_crtc *crtc = to_intel_crtc(encoder->crtc);
+	struct drm_display_mode *mode = &crtc->config->base.adjusted_mode;
+	struct drm_connector *connector;
+	struct drm_device *dev = encoder->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	connector = drm_select_eld(encoder, mode);
+	if (!connector)
+		return;
+
+	DRM_DEBUG_DRIVER("ELD on [CONNECTOR:%d:%s], [ENCODER:%d:%s]\n",
+			 connector->base.id,
+			 connector->name,
+			 connector->encoder->base.id,
+			 connector->encoder->name);
+
+	/* ELD Conn_Type */
+	connector->eld[5] &= ~(3 << 2);
+	if (intel_pipe_has_type(crtc, INTEL_OUTPUT_DISPLAYPORT))
+		connector->eld[5] |= (1 << 2);
+
+	connector->eld[6] = drm_av_sync_delay(connector, mode) / 2;
+
+	if (dev_priv->display.audio_codec_enable)
+		dev_priv->display.audio_codec_enable(connector, intel_encoder, mode);
+}
+
+/**
+ * intel_audio_codec_disable - Disable the audio codec for HD audio
+ * @encoder: encoder on which to disable audio
+ *
+ * The disable sequences must be performed before disabling the transcoder or
+ * port.
+ */
+void intel_audio_codec_disable(struct intel_encoder *encoder)
+{
+	struct drm_device *dev = encoder->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	if (dev_priv->display.audio_codec_disable)
+		dev_priv->display.audio_codec_disable(encoder);
+}
+
+/**
+ * intel_init_audio - Set up chip specific audio functions
+ * @dev: drm device
+ */
+void intel_init_audio(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	if (IS_G4X(dev)) {
+		dev_priv->display.audio_codec_enable = g4x_audio_codec_enable;
+		dev_priv->display.audio_codec_disable = g4x_audio_codec_disable;
+	} else if (IS_VALLEYVIEW(dev)) {
+		dev_priv->display.audio_codec_enable = ilk_audio_codec_enable;
+		dev_priv->display.audio_codec_disable = ilk_audio_codec_disable;
+	} else if (IS_HASWELL(dev) || INTEL_INFO(dev)->gen >= 8) {
+		dev_priv->display.audio_codec_enable = hsw_audio_codec_enable;
+		dev_priv->display.audio_codec_disable = hsw_audio_codec_disable;
+	} else if (HAS_PCH_SPLIT(dev)) {
+		dev_priv->display.audio_codec_enable = ilk_audio_codec_enable;
+		dev_priv->display.audio_codec_disable = ilk_audio_codec_disable;
+	}
+}
+
+static void i915_audio_component_get_power(struct device *dev)
+{
+	intel_display_power_get(dev_to_i915(dev), POWER_DOMAIN_AUDIO);
+}
+
+static void i915_audio_component_put_power(struct device *dev)
+{
+	intel_display_power_put(dev_to_i915(dev), POWER_DOMAIN_AUDIO);
+}
+
+/* Get CDCLK in kHz  */
+static int i915_audio_component_get_cdclk_freq(struct device *dev)
+{
+	struct drm_i915_private *dev_priv = dev_to_i915(dev);
+	int ret;
+
+	if (WARN_ON_ONCE(!HAS_DDI(dev_priv)))
+		return -ENODEV;
+
+	intel_display_power_get(dev_priv, POWER_DOMAIN_AUDIO);
+	ret = intel_ddi_get_cdclk_freq(dev_priv);
+	intel_display_power_put(dev_priv, POWER_DOMAIN_AUDIO);
+
+	return ret;
+}
+
+static const struct i915_audio_component_ops i915_audio_component_ops = {
+	.owner		= THIS_MODULE,
+	.get_power	= i915_audio_component_get_power,
+	.put_power	= i915_audio_component_put_power,
+	.get_cdclk_freq	= i915_audio_component_get_cdclk_freq,
+};
+
+static int i915_audio_component_bind(struct device *i915_dev,
+				     struct device *hda_dev, void *data)
+{
+	struct i915_audio_component *acomp = data;
+
+	if (WARN_ON(acomp->ops || acomp->dev))
+		return -EEXIST;
+
+	acomp->ops = &i915_audio_component_ops;
+	acomp->dev = i915_dev;
+
+	return 0;
+}
+
+static void i915_audio_component_unbind(struct device *i915_dev,
+					struct device *hda_dev, void *data)
+{
+	struct i915_audio_component *acomp = data;
+
+	acomp->ops = NULL;
+	acomp->dev = NULL;
+}
+
+static const struct component_ops i915_audio_component_bind_ops = {
+	.bind	= i915_audio_component_bind,
+	.unbind	= i915_audio_component_unbind,
+};
+
+/**
+ * i915_audio_component_init - initialize and register the audio component
+ * @dev_priv: i915 device instance
+ *
+ * This will register with the component framework a child component which
+ * will bind dynamically to the snd_hda_intel driver's corresponding master
+ * component when the latter is registered. During binding the child
+ * initializes an instance of struct i915_audio_component which it receives
+ * from the master. The master can then start to use the interface defined by
+ * this struct. Each side can break the binding at any point by deregistering
+ * its own component after which each side's component unbind callback is
+ * called.
+ *
+ * We ignore any error during registration and continue with reduced
+ * functionality (i.e. without HDMI audio).
+ */
+void i915_audio_component_init(struct drm_i915_private *dev_priv)
+{
+	int ret;
+
+	ret = component_add(dev_priv->dev->dev, &i915_audio_component_bind_ops);
+	if (ret < 0) {
+		DRM_ERROR("failed to add audio component (%d)\n", ret);
+		/* continue with reduced functionality */
+		return;
+	}
+
+	dev_priv->audio_component_registered = true;
+}
+
+/**
+ * i915_audio_component_cleanup - deregister the audio component
+ * @dev_priv: i915 device instance
+ *
+ * Deregisters the audio component, breaking any existing binding to the
+ * corresponding snd_hda_intel driver's master component.
+ */
+void i915_audio_component_cleanup(struct drm_i915_private *dev_priv)
+{
+	if (!dev_priv->audio_component_registered)
+		return;
+
+	component_del(dev_priv->dev->dev, &i915_audio_component_bind_ops);
+	dev_priv->audio_component_registered = false;
+}