diff mbox series

[v8,04/19] video/hdmi: Add audio_infoframe packing for DP

Message ID 20220218145437.18563-5-granquet@baylibre.com (mailing list archive)
State Handled Elsewhere
Headers show
Series drm/mediatek: Add mt8195 DisplayPort driver | expand

Commit Message

Guillaume Ranquet Feb. 18, 2022, 2:54 p.m. UTC
From: Markus Schneider-Pargmann <msp@baylibre.com>

Similar to HDMI, DP uses audio infoframes as well which are structured
very similar to the HDMI ones.

This patch adds a helper function to pack the HDMI audio infoframe for
DP, called hdmi_audio_infoframe_pack_for_dp().
hdmi_audio_infoframe_pack_only() is split into two parts. One of them
packs the payload only and can be used for HDMI and DP.

Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
---
 drivers/video/hdmi.c        | 83 ++++++++++++++++++++++++++++---------
 include/drm/drm_dp_helper.h |  2 +
 include/linux/hdmi.h        |  7 +++-
 3 files changed, 72 insertions(+), 20 deletions(-)

Comments

AngeloGioacchino Del Regno Feb. 21, 2022, 2:30 p.m. UTC | #1
Il 18/02/22 15:54, Guillaume Ranquet ha scritto:
> From: Markus Schneider-Pargmann <msp@baylibre.com>
> 
> Similar to HDMI, DP uses audio infoframes as well which are structured
> very similar to the HDMI ones.
> 
> This patch adds a helper function to pack the HDMI audio infoframe for
> DP, called hdmi_audio_infoframe_pack_for_dp().
> hdmi_audio_infoframe_pack_only() is split into two parts. One of them
> packs the payload only and can be used for HDMI and DP.
> 
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> ---
>   drivers/video/hdmi.c        | 83 ++++++++++++++++++++++++++++---------
>   include/drm/drm_dp_helper.h |  2 +
>   include/linux/hdmi.h        |  7 +++-
>   3 files changed, 72 insertions(+), 20 deletions(-)
> 
> diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
> index 947be761dfa40..63e74d9fd210e 100644
> --- a/drivers/video/hdmi.c
> +++ b/drivers/video/hdmi.c
> @@ -21,6 +21,7 @@
>    * DEALINGS IN THE SOFTWARE.
>    */
>   
> +#include <drm/drm_dp_helper.h>
>   #include <linux/bitops.h>
>   #include <linux/bug.h>
>   #include <linux/errno.h>
> @@ -381,12 +382,34 @@ static int hdmi_audio_infoframe_check_only(const struct hdmi_audio_infoframe *fr
>    *
>    * Returns 0 on success or a negative error code on failure.
>    */
> -int hdmi_audio_infoframe_check(struct hdmi_audio_infoframe *frame)
> +int hdmi_audio_infoframe_check(const struct hdmi_audio_infoframe *frame)
>   {
>   	return hdmi_audio_infoframe_check_only(frame);
>   }
>   EXPORT_SYMBOL(hdmi_audio_infoframe_check);
>   
> +static void
> +hdmi_audio_infoframe_pack_payload(const struct hdmi_audio_infoframe *frame,
> +				  u8 *buffer)
> +{
> +	u8 channels;
> +
> +	if (frame->channels >= 2)
> +		channels = frame->channels - 1;
> +	else
> +		channels = 0;
> +
> +	buffer[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
> +	buffer[1] = ((frame->sample_frequency & 0x7) << 2) |
> +		 (frame->sample_size & 0x3);
> +	buffer[2] = frame->coding_type_ext & 0x1f;
> +	buffer[3] = frame->channel_allocation;
> +	buffer[4] = (frame->level_shift_value & 0xf) << 3;
> +
> +	if (frame->downmix_inhibit)
> +		buffer[4] |= BIT(7);
> +}
> +
>   /**
>    * hdmi_audio_infoframe_pack_only() - write HDMI audio infoframe to binary buffer
>    * @frame: HDMI audio infoframe
> @@ -404,7 +427,6 @@ EXPORT_SYMBOL(hdmi_audio_infoframe_check);
>   ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
>   				       void *buffer, size_t size)
>   {
> -	unsigned char channels;
>   	u8 *ptr = buffer;
>   	size_t length;
>   	int ret;
> @@ -420,28 +442,13 @@ ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
>   
>   	memset(buffer, 0, size);
>   
> -	if (frame->channels >= 2)
> -		channels = frame->channels - 1;
> -	else
> -		channels = 0;
> -
>   	ptr[0] = frame->type;
>   	ptr[1] = frame->version;
>   	ptr[2] = frame->length;
>   	ptr[3] = 0; /* checksum */
>   
> -	/* start infoframe payload */
> -	ptr += HDMI_INFOFRAME_HEADER_SIZE;
> -
> -	ptr[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
> -	ptr[1] = ((frame->sample_frequency & 0x7) << 2) |
> -		 (frame->sample_size & 0x3);
> -	ptr[2] = frame->coding_type_ext & 0x1f;
> -	ptr[3] = frame->channel_allocation;
> -	ptr[4] = (frame->level_shift_value & 0xf) << 3;
> -
> -	if (frame->downmix_inhibit)
> -		ptr[4] |= BIT(7);
> +	hdmi_audio_infoframe_pack_payload(frame,
> +					  ptr + HDMI_INFOFRAME_HEADER_SIZE);
>   
>   	hdmi_infoframe_set_checksum(buffer, length);
>   
> @@ -479,6 +486,44 @@ ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame,
>   }
>   EXPORT_SYMBOL(hdmi_audio_infoframe_pack);
>   
> +/**
> + * hdmi_audio_infoframe_pack_for_dp - Pack a HDMI Audio infoframe for
> + *                                    displayport

This fits in one line (82 cols is ok)... but, anyway, please capitalize D and P
in the DisplayPort word.

> + *
> + * @frame HDMI Audio infoframe

You're almost there! You missed a colon after each description.
Also, I personally like seeing indented descriptions as, in my opinion, this
enhances human readability, as it's a bit more pleasing to the eye... but
it's not a requirement, so you be the judge.

* @frame:      HDMI Audio infoframe
* @sdp:        Secondary data packet......
* @dp_version: DisplayPort version......

Please fix.

> + * @sdp secondary data packet for display port. This is filled with the
> + * appropriate data
> + * @dp_version Display Port version to be encoded in the header
> + *
> + * Packs a HDMI Audio Infoframe to be sent over Display Port. This function
> + * fills the secondary data packet to be used for Display Port.
> + *
> + * Return: Number of total written bytes or a negative errno on failure.
> + */
> +ssize_t
> +hdmi_audio_infoframe_pack_for_dp(const struct hdmi_audio_infoframe *frame,
> +				 struct dp_sdp *sdp, u8 dp_version)
> +{
> +	int ret;
> +
> +	ret = hdmi_audio_infoframe_check(frame);
> +	if (ret)
> +		return ret;
> +
> +	memset(sdp->db, 0, sizeof(sdp->db));
> +
> +	// Secondary-data packet header

Please, C-style comments:

	/* Secondary-data packet header */

Thanks,
Angelo
AngeloGioacchino Del Regno Feb. 22, 2022, 3:16 p.m. UTC | #2
Il 18/02/22 15:54, Guillaume Ranquet ha scritto:
> From: Markus Schneider-Pargmann <msp@baylibre.com>
> 
> Similar to HDMI, DP uses audio infoframes as well which are structured
> very similar to the HDMI ones.
> 
> This patch adds a helper function to pack the HDMI audio infoframe for
> DP, called hdmi_audio_infoframe_pack_for_dp().
> hdmi_audio_infoframe_pack_only() is split into two parts. One of them
> packs the payload only and can be used for HDMI and DP.
> 
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>

Hello Guillaume,

I've just noticed that this patch will not apply against the latest linux-next,
as the include/drm/drm_dp_helper.h header was moved to
include/drm/dp/drm_dp_helper.h

Can you please rebase for v9?

Thanks,
Angelo

> ---
>   drivers/video/hdmi.c        | 83 ++++++++++++++++++++++++++++---------
>   include/drm/drm_dp_helper.h |  2 +
>   include/linux/hdmi.h        |  7 +++-
>   3 files changed, 72 insertions(+), 20 deletions(-)
>
Guillaume Ranquet Feb. 25, 2022, 10:38 a.m. UTC | #3
Quoting AngeloGioacchino Del Regno (2022-02-21 15:30:07)
> Il 18/02/22 15:54, Guillaume Ranquet ha scritto:
> > From: Markus Schneider-Pargmann <msp@baylibre.com>
> >
> > Similar to HDMI, DP uses audio infoframes as well which are structured
> > very similar to the HDMI ones.
> >
> > This patch adds a helper function to pack the HDMI audio infoframe for
> > DP, called hdmi_audio_infoframe_pack_for_dp().
> > hdmi_audio_infoframe_pack_only() is split into two parts. One of them
> > packs the payload only and can be used for HDMI and DP.
> >
> > Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> > Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> > ---
> >   drivers/video/hdmi.c        | 83 ++++++++++++++++++++++++++++---------
> >   include/drm/drm_dp_helper.h |  2 +
> >   include/linux/hdmi.h        |  7 +++-
> >   3 files changed, 72 insertions(+), 20 deletions(-)
> >
> > diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
> > index 947be761dfa40..63e74d9fd210e 100644
> > --- a/drivers/video/hdmi.c
> > +++ b/drivers/video/hdmi.c
> > @@ -21,6 +21,7 @@
> >    * DEALINGS IN THE SOFTWARE.
> >    */
> >
> > +#include <drm/drm_dp_helper.h>
> >   #include <linux/bitops.h>
> >   #include <linux/bug.h>
> >   #include <linux/errno.h>
> > @@ -381,12 +382,34 @@ static int hdmi_audio_infoframe_check_only(const struct hdmi_audio_infoframe *fr
> >    *
> >    * Returns 0 on success or a negative error code on failure.
> >    */
> > -int hdmi_audio_infoframe_check(struct hdmi_audio_infoframe *frame)
> > +int hdmi_audio_infoframe_check(const struct hdmi_audio_infoframe *frame)
> >   {
> >       return hdmi_audio_infoframe_check_only(frame);
> >   }
> >   EXPORT_SYMBOL(hdmi_audio_infoframe_check);
> >
> > +static void
> > +hdmi_audio_infoframe_pack_payload(const struct hdmi_audio_infoframe *frame,
> > +                               u8 *buffer)
> > +{
> > +     u8 channels;
> > +
> > +     if (frame->channels >= 2)
> > +             channels = frame->channels - 1;
> > +     else
> > +             channels = 0;
> > +
> > +     buffer[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
> > +     buffer[1] = ((frame->sample_frequency & 0x7) << 2) |
> > +              (frame->sample_size & 0x3);
> > +     buffer[2] = frame->coding_type_ext & 0x1f;
> > +     buffer[3] = frame->channel_allocation;
> > +     buffer[4] = (frame->level_shift_value & 0xf) << 3;
> > +
> > +     if (frame->downmix_inhibit)
> > +             buffer[4] |= BIT(7);
> > +}
> > +
> >   /**
> >    * hdmi_audio_infoframe_pack_only() - write HDMI audio infoframe to binary buffer
> >    * @frame: HDMI audio infoframe
> > @@ -404,7 +427,6 @@ EXPORT_SYMBOL(hdmi_audio_infoframe_check);
> >   ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
> >                                      void *buffer, size_t size)
> >   {
> > -     unsigned char channels;
> >       u8 *ptr = buffer;
> >       size_t length;
> >       int ret;
> > @@ -420,28 +442,13 @@ ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
> >
> >       memset(buffer, 0, size);
> >
> > -     if (frame->channels >= 2)
> > -             channels = frame->channels - 1;
> > -     else
> > -             channels = 0;
> > -
> >       ptr[0] = frame->type;
> >       ptr[1] = frame->version;
> >       ptr[2] = frame->length;
> >       ptr[3] = 0; /* checksum */
> >
> > -     /* start infoframe payload */
> > -     ptr += HDMI_INFOFRAME_HEADER_SIZE;
> > -
> > -     ptr[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
> > -     ptr[1] = ((frame->sample_frequency & 0x7) << 2) |
> > -              (frame->sample_size & 0x3);
> > -     ptr[2] = frame->coding_type_ext & 0x1f;
> > -     ptr[3] = frame->channel_allocation;
> > -     ptr[4] = (frame->level_shift_value & 0xf) << 3;
> > -
> > -     if (frame->downmix_inhibit)
> > -             ptr[4] |= BIT(7);
> > +     hdmi_audio_infoframe_pack_payload(frame,
> > +                                       ptr + HDMI_INFOFRAME_HEADER_SIZE);
> >
> >       hdmi_infoframe_set_checksum(buffer, length);
> >
> > @@ -479,6 +486,44 @@ ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame,
> >   }
> >   EXPORT_SYMBOL(hdmi_audio_infoframe_pack);
> >
> > +/**
> > + * hdmi_audio_infoframe_pack_for_dp - Pack a HDMI Audio infoframe for
> > + *                                    displayport
>
> This fits in one line (82 cols is ok)... but, anyway, please capitalize D and P
> in the DisplayPort word.
>

Yeah, I ran clang-format and didn't want to contradict the tool :)
I'll fix that for v9

> > + *
> > + * @frame HDMI Audio infoframe
>
> You're almost there! You missed a colon after each description.
> Also, I personally like seeing indented descriptions as, in my opinion, this
> enhances human readability, as it's a bit more pleasing to the eye... but
> it's not a requirement, so you be the judge.
>
> * @frame:      HDMI Audio infoframe
> * @sdp:        Secondary data packet......
> * @dp_version: DisplayPort version......
>
> Please fix.
>

I completly forgot to generate and check the kerneldoc.
Sorry.

> > + * @sdp secondary data packet for display port. This is filled with the
> > + * appropriate data
> > + * @dp_version Display Port version to be encoded in the header
> > + *
> > + * Packs a HDMI Audio Infoframe to be sent over Display Port. This function
> > + * fills the secondary data packet to be used for Display Port.
> > + *
> > + * Return: Number of total written bytes or a negative errno on failure.
> > + */
> > +ssize_t
> > +hdmi_audio_infoframe_pack_for_dp(const struct hdmi_audio_infoframe *frame,
> > +                              struct dp_sdp *sdp, u8 dp_version)
> > +{
> > +     int ret;
> > +
> > +     ret = hdmi_audio_infoframe_check(frame);
> > +     if (ret)
> > +             return ret;
> > +
> > +     memset(sdp->db, 0, sizeof(sdp->db));
> > +
> > +     // Secondary-data packet header
>
> Please, C-style comments:
>
>         /* Secondary-data packet header */
>
> Thanks,
> Angelo

I think this is not the only case of C++ comment that slipped past me...
I'll revise the whole series.

Thx,
Guillaume.
Guillaume Ranquet Feb. 25, 2022, 10:40 a.m. UTC | #4
Quoting AngeloGioacchino Del Regno (2022-02-22 16:16:48)
> Il 18/02/22 15:54, Guillaume Ranquet ha scritto:
> > From: Markus Schneider-Pargmann <msp@baylibre.com>
> >
> > Similar to HDMI, DP uses audio infoframes as well which are structured
> > very similar to the HDMI ones.
> >
> > This patch adds a helper function to pack the HDMI audio infoframe for
> > DP, called hdmi_audio_infoframe_pack_for_dp().
> > hdmi_audio_infoframe_pack_only() is split into two parts. One of them
> > packs the payload only and can be used for HDMI and DP.
> >
> > Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> > Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
>
> Hello Guillaume,
>
> I've just noticed that this patch will not apply against the latest linux-next,
> as the include/drm/drm_dp_helper.h header was moved to
> include/drm/dp/drm_dp_helper.h
>
> Can you please rebase for v9?
>
> Thanks,
> Angelo
>

I'm sorry, I'm a bit of a noob, I rebased this series against 5.17-rc4 ...
I'll rebase v9 against linux-next.

Thx,
Guillaume.

> > ---
> >   drivers/video/hdmi.c        | 83 ++++++++++++++++++++++++++++---------
> >   include/drm/drm_dp_helper.h |  2 +
> >   include/linux/hdmi.h        |  7 +++-
> >   3 files changed, 72 insertions(+), 20 deletions(-)
> >
diff mbox series

Patch

diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
index 947be761dfa40..63e74d9fd210e 100644
--- a/drivers/video/hdmi.c
+++ b/drivers/video/hdmi.c
@@ -21,6 +21,7 @@ 
  * DEALINGS IN THE SOFTWARE.
  */
 
+#include <drm/drm_dp_helper.h>
 #include <linux/bitops.h>
 #include <linux/bug.h>
 #include <linux/errno.h>
@@ -381,12 +382,34 @@  static int hdmi_audio_infoframe_check_only(const struct hdmi_audio_infoframe *fr
  *
  * Returns 0 on success or a negative error code on failure.
  */
-int hdmi_audio_infoframe_check(struct hdmi_audio_infoframe *frame)
+int hdmi_audio_infoframe_check(const struct hdmi_audio_infoframe *frame)
 {
 	return hdmi_audio_infoframe_check_only(frame);
 }
 EXPORT_SYMBOL(hdmi_audio_infoframe_check);
 
+static void
+hdmi_audio_infoframe_pack_payload(const struct hdmi_audio_infoframe *frame,
+				  u8 *buffer)
+{
+	u8 channels;
+
+	if (frame->channels >= 2)
+		channels = frame->channels - 1;
+	else
+		channels = 0;
+
+	buffer[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
+	buffer[1] = ((frame->sample_frequency & 0x7) << 2) |
+		 (frame->sample_size & 0x3);
+	buffer[2] = frame->coding_type_ext & 0x1f;
+	buffer[3] = frame->channel_allocation;
+	buffer[4] = (frame->level_shift_value & 0xf) << 3;
+
+	if (frame->downmix_inhibit)
+		buffer[4] |= BIT(7);
+}
+
 /**
  * hdmi_audio_infoframe_pack_only() - write HDMI audio infoframe to binary buffer
  * @frame: HDMI audio infoframe
@@ -404,7 +427,6 @@  EXPORT_SYMBOL(hdmi_audio_infoframe_check);
 ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
 				       void *buffer, size_t size)
 {
-	unsigned char channels;
 	u8 *ptr = buffer;
 	size_t length;
 	int ret;
@@ -420,28 +442,13 @@  ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
 
 	memset(buffer, 0, size);
 
-	if (frame->channels >= 2)
-		channels = frame->channels - 1;
-	else
-		channels = 0;
-
 	ptr[0] = frame->type;
 	ptr[1] = frame->version;
 	ptr[2] = frame->length;
 	ptr[3] = 0; /* checksum */
 
-	/* start infoframe payload */
-	ptr += HDMI_INFOFRAME_HEADER_SIZE;
-
-	ptr[0] = ((frame->coding_type & 0xf) << 4) | (channels & 0x7);
-	ptr[1] = ((frame->sample_frequency & 0x7) << 2) |
-		 (frame->sample_size & 0x3);
-	ptr[2] = frame->coding_type_ext & 0x1f;
-	ptr[3] = frame->channel_allocation;
-	ptr[4] = (frame->level_shift_value & 0xf) << 3;
-
-	if (frame->downmix_inhibit)
-		ptr[4] |= BIT(7);
+	hdmi_audio_infoframe_pack_payload(frame,
+					  ptr + HDMI_INFOFRAME_HEADER_SIZE);
 
 	hdmi_infoframe_set_checksum(buffer, length);
 
@@ -479,6 +486,44 @@  ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame,
 }
 EXPORT_SYMBOL(hdmi_audio_infoframe_pack);
 
+/**
+ * hdmi_audio_infoframe_pack_for_dp - Pack a HDMI Audio infoframe for
+ *                                    displayport
+ *
+ * @frame HDMI Audio infoframe
+ * @sdp secondary data packet for display port. This is filled with the
+ * appropriate data
+ * @dp_version Display Port version to be encoded in the header
+ *
+ * Packs a HDMI Audio Infoframe to be sent over Display Port. This function
+ * fills the secondary data packet to be used for Display Port.
+ *
+ * Return: Number of total written bytes or a negative errno on failure.
+ */
+ssize_t
+hdmi_audio_infoframe_pack_for_dp(const struct hdmi_audio_infoframe *frame,
+				 struct dp_sdp *sdp, u8 dp_version)
+{
+	int ret;
+
+	ret = hdmi_audio_infoframe_check(frame);
+	if (ret)
+		return ret;
+
+	memset(sdp->db, 0, sizeof(sdp->db));
+
+	// Secondary-data packet header
+	sdp->sdp_header.HB0 = 0;
+	sdp->sdp_header.HB1 = frame->type;
+	sdp->sdp_header.HB2 = DP_SDP_AUDIO_INFOFRAME_HB2;
+	sdp->sdp_header.HB3 = (dp_version & 0x3f) << 2;
+
+	hdmi_audio_infoframe_pack_payload(frame, sdp->db);
+
+	return frame->length + 4;
+}
+EXPORT_SYMBOL(hdmi_audio_infoframe_pack_for_dp);
+
 /**
  * hdmi_vendor_infoframe_init() - initialize an HDMI vendor infoframe
  * @frame: HDMI vendor infoframe
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index 30359e434c3f3..707927e3e773a 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -1567,6 +1567,8 @@  int drm_dp_bw_code_to_link_rate(u8 link_bw);
 #define DP_SDP_VSC_EXT_CEA		0x21 /* DP 1.4 */
 /* 0x80+ CEA-861 infoframe types */
 
+#define DP_SDP_AUDIO_INFOFRAME_HB2	0x1b
+
 /**
  * struct dp_sdp_header - DP secondary data packet header
  * @HB0: Secondary Data Packet ID
diff --git a/include/linux/hdmi.h b/include/linux/hdmi.h
index c8ec982ff4984..2f4dcc8d060e3 100644
--- a/include/linux/hdmi.h
+++ b/include/linux/hdmi.h
@@ -336,7 +336,12 @@  ssize_t hdmi_audio_infoframe_pack(struct hdmi_audio_infoframe *frame,
 				  void *buffer, size_t size);
 ssize_t hdmi_audio_infoframe_pack_only(const struct hdmi_audio_infoframe *frame,
 				       void *buffer, size_t size);
-int hdmi_audio_infoframe_check(struct hdmi_audio_infoframe *frame);
+int hdmi_audio_infoframe_check(const struct hdmi_audio_infoframe *frame);
+
+struct dp_sdp;
+ssize_t
+hdmi_audio_infoframe_pack_for_dp(const struct hdmi_audio_infoframe *frame,
+				 struct dp_sdp *sdp, u8 dp_version);
 
 enum hdmi_3d_structure {
 	HDMI_3D_STRUCTURE_INVALID = -1,