diff mbox series

[v10,05/21] video/hdmi: Add audio_infoframe packing for DP

Message ID 20220523104758.29531-6-granquet@baylibre.com
State Not Applicable
Headers show
Series drm/mediatek: Add mt8195 DisplayPort driver | expand

Commit Message

Guillaume Ranquet May 23, 2022, 10:47 a.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.

Also constify the frame parameter in hdmi_audio_infoframe_check() as
it is passed to hdmi_audio_infoframe_check_only() which expects a const.

Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
---
 drivers/video/hdmi.c           | 82 ++++++++++++++++++++++++++--------
 include/drm/dp/drm_dp_helper.h |  2 +
 include/linux/hdmi.h           |  7 ++-
 3 files changed, 71 insertions(+), 20 deletions(-)

Comments

AngeloGioacchino Del Regno May 25, 2022, 12:32 p.m. UTC | #1
Il 23/05/22 12:47, 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.
> 
> Also constify the frame parameter in hdmi_audio_infoframe_check() as
> it is passed to hdmi_audio_infoframe_check_only() which expects a const.
> 
> Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> ---
>   drivers/video/hdmi.c           | 82 ++++++++++++++++++++++++++--------
>   include/drm/dp/drm_dp_helper.h |  2 +

this has been moved... again... this time it's include/drm/display/drm_dp_helper.h

>   include/linux/hdmi.h           |  7 ++-
>   3 files changed, 71 insertions(+), 20 deletions(-)
>
Rex-BC Chen (陳柏辰) June 7, 2022, 3:10 a.m. UTC | #2
On Wed, 2022-05-25 at 14:32 +0200, AngeloGioacchino Del Regno wrote:
> Il 23/05/22 12:47, 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.
> > 
> > Also constify the frame parameter in hdmi_audio_infoframe_check()
> > as
> > it is passed to hdmi_audio_infoframe_check_only() which expects a
> > const.
> > 
> > Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com>
> > Signed-off-by: Guillaume Ranquet <granquet@baylibre.com>
> > ---
> >   drivers/video/hdmi.c           | 82 ++++++++++++++++++++++++++---
> > -----
> >   include/drm/dp/drm_dp_helper.h |  2 +
> 
> this has been moved... again... this time it's
> include/drm/display/drm_dp_helper.h
> 

Hello Angelo,

yes, I will rebase on 5.19-rc1 and fix this in next version.

BRs,
Bo-Chen
> >   include/linux/hdmi.h           |  7 ++-
> >   3 files changed, 71 insertions(+), 20 deletions(-)
> > 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff mbox series

Patch

diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
index 947be761dfa4..5f50237554ed 100644
--- a/drivers/video/hdmi.c
+++ b/drivers/video/hdmi.c
@@ -21,6 +21,7 @@ 
  * DEALINGS IN THE SOFTWARE.
  */
 
+#include <drm/dp/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 +486,43 @@  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/dp/drm_dp_helper.h b/include/drm/dp/drm_dp_helper.h
index 51e02cf75277..d4adb479263e 100644
--- a/include/drm/dp/drm_dp_helper.h
+++ b/include/drm/dp/drm_dp_helper.h
@@ -1576,6 +1576,8 @@  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 c8ec982ff498..2f4dcc8d060e 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,