drivers/media/common/cx2341x.c

Source file repositories/reference/linux-study-clean/drivers/media/common/cx2341x.c

File Facts

System
Linux kernel
Corpus path
drivers/media/common/cx2341x.c
Extension
.c
Size
57220 bytes
Lines
1779
Domain
Driver Families
Bucket
drivers/media
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (params->capabilities & CX2341X_CAP_HAS_AC3) {
			/*
			 * The state of L2 & AC3 bitrate controls can change
			 * when this control changes, but v4l2_ctrl_query_fill()
			 * already sets V4L2_CTRL_FLAG_UPDATE for
			 * V4L2_CID_MPEG_AUDIO_ENCODING, so we don't here.
			 */
			return v4l2_ctrl_query_fill(qctrl,
					V4L2_MPEG_AUDIO_ENCODING_LAYER_2,
					V4L2_MPEG_AUDIO_ENCODING_AC3, 1,
					default_params.audio_encoding);
		}

		return v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_ENCODING_LAYER_2,
				V4L2_MPEG_AUDIO_ENCODING_LAYER_2, 1,
				default_params.audio_encoding);

	case V4L2_CID_MPEG_AUDIO_L2_BITRATE:
		err = v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_L2_BITRATE_192K,
				V4L2_MPEG_AUDIO_L2_BITRATE_384K, 1,
				default_params.audio_l2_bitrate);
		if (err)
			return err;
		if (params->capabilities & CX2341X_CAP_HAS_AC3 &&
		    params->audio_encoding != V4L2_MPEG_AUDIO_ENCODING_LAYER_2)
			qctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
		return 0;

	case V4L2_CID_MPEG_AUDIO_MODE:
		return v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_MODE_STEREO,
				V4L2_MPEG_AUDIO_MODE_MONO, 1,
				V4L2_MPEG_AUDIO_MODE_STEREO);

	case V4L2_CID_MPEG_AUDIO_MODE_EXTENSION:
		err = v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4,
				V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_16, 1,
				V4L2_MPEG_AUDIO_MODE_EXTENSION_BOUND_4);
		if (err == 0 &&
		    params->audio_mode != V4L2_MPEG_AUDIO_MODE_JOINT_STEREO)
			qctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
		return err;

	case V4L2_CID_MPEG_AUDIO_EMPHASIS:
		return v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_EMPHASIS_NONE,
				V4L2_MPEG_AUDIO_EMPHASIS_CCITT_J17, 1,
				V4L2_MPEG_AUDIO_EMPHASIS_NONE);

	case V4L2_CID_MPEG_AUDIO_CRC:
		return v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_CRC_NONE,
				V4L2_MPEG_AUDIO_CRC_CRC16, 1,
				V4L2_MPEG_AUDIO_CRC_NONE);

	case V4L2_CID_MPEG_AUDIO_MUTE:
		return v4l2_ctrl_query_fill(qctrl, 0, 1, 1, 0);

	case V4L2_CID_MPEG_AUDIO_AC3_BITRATE:
		err = v4l2_ctrl_query_fill(qctrl,
				V4L2_MPEG_AUDIO_AC3_BITRATE_48K,
				V4L2_MPEG_AUDIO_AC3_BITRATE_448K, 1,
				default_params.audio_ac3_bitrate);
		if (err)
			return err;
		if (params->capabilities & CX2341X_CAP_HAS_AC3) {
			if (params->audio_encoding !=
						   V4L2_MPEG_AUDIO_ENCODING_AC3)
				qctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
		} else
			qctrl->flags |= V4L2_CTRL_FLAG_DISABLED;
		return 0;

	case V4L2_CID_MPEG_VIDEO_ENCODING:
		/* this setting is read-only for the cx2341x since the
		   V4L2_CID_MPEG_STREAM_TYPE really determines the
		   MPEG-1/2 setting */
		err = v4l2_ctrl_query_fill(qctrl,
					   V4L2_MPEG_VIDEO_ENCODING_MPEG_1,
					   V4L2_MPEG_VIDEO_ENCODING_MPEG_2, 1,
					   V4L2_MPEG_VIDEO_ENCODING_MPEG_2);
		if (err == 0)
			qctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
		return err;

	case V4L2_CID_MPEG_VIDEO_ASPECT:
		return v4l2_ctrl_query_fill(qctrl,

Annotation

Implementation Notes