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
+ *
+ * @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,
--
2.34.1
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
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.
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(-) >
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(-) > >
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