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authorMarkus Schneider-Pargmann <msp@baylibre.com>2022-09-01 12:41:41 +0800
committerDmitry Osipenko <dmitry.osipenko@collabora.com>2022-09-04 15:31:59 +0300
commitf89aa0b6db18dea3c3c8ef266cc6c9fd8dff2d72 (patch)
treee8e6a27c1647faa6d72964d2dd51f5c868e3b88f /drivers/video
parenta2ce58e8f9e4cef389a04077d052f8135f380c5c (diff)
video/hdmi: Add audio_infoframe packing for DP
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> Signed-off-by: Bo-Chen Chen <rex-bc.chen@mediatek.com> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Link: https://patchwork.freedesktop.org/patch/msgid/20220901044149.16782-3-rex-bc.chen@mediatek.com
Diffstat (limited to 'drivers/video')
-rw-r--r--drivers/video/hdmi.c82
1 files changed, 63 insertions, 19 deletions
diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
index 947be761dfa4..03c7f27dde49 100644
--- a/drivers/video/hdmi.c
+++ b/drivers/video/hdmi.c
@@ -21,6 +21,7 @@
* DEALINGS IN THE SOFTWARE.
*/
+#include <drm/display/drm_dp.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);
@@ -480,6 +487,43 @@ 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 DisplayPort.
+ * @dp_version: DisplayPort version to be encoded in the header
+ *
+ * Packs a HDMI Audio Infoframe to be sent over DisplayPort. This function
+ * fills the secondary data packet to be used for DisplayPort.
+ *
+ * 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 size = frame length + four HB for sdp_header */
+ 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
*