On Wed, Oct 25, 2023 at 6:47 PM Hans Verkuil [off-list ref] wrote:

On 20/10/2023 11:30, Shengjiu Wang wrote:

quoted

Add V4L2_CID_M2M_AUDIO_SOURCE_RATE and V4L2_CID_M2M_AUDIO_DEST_RATE
new IDs for rate control.

Add V4L2_CID_M2M_AUDIO_SOURCE_RATE_OFFSET and
V4L2_CID_M2M_AUDIO_DEST_RATE_OFFSET for clock drift.

Signed-off-by: Shengjiu Wang <redacted>
---
 .../media/v4l/ext-ctrls-audio-m2m.rst          | 18 ++++++++++++++++++
 drivers/media/v4l2-core/v4l2-ctrls-defs.c      | 12 ++++++++++++
 include/uapi/linux/v4l2-controls.h             |  5 +++++
 3 files changed, 35 insertions(+)

diff --git a/Documentation/userspace-api/media/v4l/ext-ctrls-audio-m2m.rst b/Documentation/userspace-api/media/v4l/ext-ctrls-audio-m2m.rst
index 82d2ecedbfee..e6972a2d3b17 100644
--- a/Documentation/userspace-api/media/v4l/ext-ctrls-audio-m2m.rst
+++ b/Documentation/userspace-api/media/v4l/ext-ctrls-audio-m2m.rst

@@ -19,3 +19,21 @@ Audio M2M Control IDs
     The Audio M2M class descriptor. Calling
     :ref:`VIDIOC_QUERYCTRL` for this control will
     return a description of this control class.
+
+.. _v4l2-audio-asrc:
+
+``V4L2_CID_M2M_AUDIO_SOURCE_RATE``

Add ' (integer menu)' after the name.

quoted

+    Sets the audio source rate, unit is (Hz)

(Hz) -> Hz.

General question: is 'rate' good enough or should it be 'sample rate'?

Ok, will use 'sample rate'.

Best regards
Wang shengjiu

quoted

+
+``V4L2_CID_M2M_AUDIO_DEST_RATE``
+    Sets the audio destination rate, unit is (Hz)

Ditto here.

quoted

+
+``V4L2_CID_M2M_AUDIO_SOURCE_RATE_OFFSET``

Add ' (fixed point)' after the name.

quoted

+    Sets the offset for audio source rate, unit is (Hz).

for -> from the

(Hz) -> Hz

quoted

+    Offset expresses the drift of clock if there is. It is
+    equal to real rate minus ideal rate.

How about:

The offset compensates for any clock drift. The actual source audio
rate is the ideal source audio rate from ``V4L2_CID_M2M_AUDIO_SOURCE_RATE``
plus this fixed point offset.

quoted

+
+``V4L2_CID_M2M_AUDIO_DEST_RATE_OFFSET``
+    Sets the offset for audio destination rate, unit is (Hz)
+    Offset expresses the drift of clock if there is. It is
+    equal to real rate minus ideal rate.

Same changes as for V4L2_CID_M2M_AUDIO_SOURCE_RATE_OFFSET.

quoted

diff --git a/drivers/media/v4l2-core/v4l2-ctrls-defs.c b/drivers/media/v4l2-core/v4l2-ctrls-defs.c
index 2a85ea3dc92f..b695cbdd1f6e 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls-defs.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls-defs.c

@@ -1245,6 +1245,10 @@ const char *v4l2_ctrl_get_name(u32 id)

      /* Audio M2M controls */
      case V4L2_CID_M2M_AUDIO_CLASS:  return "Audio M2M Controls";
+     case V4L2_CID_M2M_AUDIO_SOURCE_RATE:    return "Audio Source Sample Rate";
+     case V4L2_CID_M2M_AUDIO_DEST_RATE:      return "Audio Dest Sample Rate";
+     case V4L2_CID_M2M_AUDIO_SOURCE_RATE_OFFSET:     return "Audio Source Sample Rate Offset";
+     case V4L2_CID_M2M_AUDIO_DEST_RATE_OFFSET:       return "Audio Dest Sample Rate Offset";

Related to my question above: "Sample Rate" or just "Rate"? Whatever we pick, it should
be consistent.

quoted

      default:
              return NULL;
      }

@@ -1606,6 +1610,14 @@ void v4l2_ctrl_fill(u32 id, const char **name, enum v4l2_ctrl_type *type,
      case V4L2_CID_COLORIMETRY_HDR10_MASTERING_DISPLAY:
              *type = V4L2_CTRL_TYPE_HDR10_MASTERING_DISPLAY;
              break;
+     case V4L2_CID_M2M_AUDIO_SOURCE_RATE:
+     case V4L2_CID_M2M_AUDIO_DEST_RATE:
+             *type = V4L2_CTRL_TYPE_INTEGER_MENU;
+             break;
+     case V4L2_CID_M2M_AUDIO_SOURCE_RATE_OFFSET:
+     case V4L2_CID_M2M_AUDIO_DEST_RATE_OFFSET:
+             *type = V4L2_CTRL_TYPE_FIXED_POINT;
+             break;
      default:
              *type = V4L2_CTRL_TYPE_INTEGER;
              break;

diff --git a/include/uapi/linux/v4l2-controls.h b/include/uapi/linux/v4l2-controls.h
index eb0f0a76f867..d433c6f0b533 100644
--- a/include/uapi/linux/v4l2-controls.h
+++ b/include/uapi/linux/v4l2-controls.h

@@ -3498,4 +3498,9 @@ struct v4l2_ctrl_av1_film_grain {
 #define V4L2_CID_M2M_AUDIO_CLASS_BASE  (V4L2_CTRL_CLASS_M2M_AUDIO | 0x900)
 #define V4L2_CID_M2M_AUDIO_CLASS       (V4L2_CTRL_CLASS_M2M_AUDIO | 1)

+#define V4L2_CID_M2M_AUDIO_SOURCE_RATE       (V4L2_CID_M2M_AUDIO_CLASS_BASE + 0)
+#define V4L2_CID_M2M_AUDIO_DEST_RATE (V4L2_CID_M2M_AUDIO_CLASS_BASE + 1)
+#define V4L2_CID_M2M_AUDIO_SOURCE_RATE_OFFSET        (V4L2_CID_M2M_AUDIO_CLASS_BASE + 2)
+#define V4L2_CID_M2M_AUDIO_DEST_RATE_OFFSET  (V4L2_CID_M2M_AUDIO_CLASS_BASE + 3)
+
 #endif

Regards,

        Hans