Commit 7aea2c0b authored by Michael Tretter's avatar Michael Tretter Committed by Mauro Carvalho Chehab
Browse files

media: allegro: add control to disable encoder buffer 



The encoder buffer can have a negative impact on the quality of the
encoded video.

Add a control to allow user space to disable the encoder buffer per
channel if the VCU supports the encoder buffer but the quality is not
sufficient.

Signed-off-by: default avatarMichael Tretter <m.tretter@pengutronix.de>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
parent 98f1cbf6

drivers/media/platform/allegro-dvt/allegro-core.c

+30 −2
Original line number Diff line number Diff line
@@ -105,6 +105,12 @@ 
#define BETA_OFFSET_DIV_2		-1

#define TC_OFFSET_DIV_2			-1



/*

 * This control allows applications to explicitly disable the encoder buffer.

 * This value is Allegro specific.

 */

#define V4L2_CID_USER_ALLEGRO_ENCODER_BUFFER (V4L2_CID_USER_ALLEGRO_BASE + 0)



static int debug;

module_param(debug, int, 0644);

MODULE_PARM_DESC(debug, "Debug level (0-2)");
@@ -275,6 +281,8 @@ struct allegro_channel { 
	struct v4l2_ctrl *mpeg_video_cpb_size;

	struct v4l2_ctrl *mpeg_video_gop_size;



	struct v4l2_ctrl *encoder_buffer;



	/* user_id is used to identify the channel during CREATE_CHANNEL */

	/* not sure, what to set here and if this is actually required */

	int user_id;
@@ -1255,7 +1263,7 @@ static int fill_create_channel_param(struct allegro_channel *channel, 
	param->max_transfo_depth_intra = channel->max_transfo_depth_intra;

	param->max_transfo_depth_inter = channel->max_transfo_depth_inter;



	param->encoder_buffer_enabled = channel->dev->has_encoder_buffer;

	param->encoder_buffer_enabled = v4l2_ctrl_g_ctrl(channel->encoder_buffer);

	param->encoder_buffer_offset = 0;



	param->rate_control_mode = channel->frame_rc_enable ?
@@ -1381,7 +1389,7 @@ static int allegro_mcu_send_encode_frame(struct allegro_dev *dev, 
					 u64 src_handle)

{

	struct mcu_msg_encode_frame msg;

	bool use_encoder_buffer = channel->dev->has_encoder_buffer;

	bool use_encoder_buffer = v4l2_ctrl_g_ctrl(channel->encoder_buffer);



	memset(&msg, 0, sizeof(msg));
@@ -2466,6 +2474,8 @@ static void allegro_destroy_channel(struct allegro_channel *channel) 
	v4l2_ctrl_grab(channel->mpeg_video_cpb_size, false);

	v4l2_ctrl_grab(channel->mpeg_video_gop_size, false);



	v4l2_ctrl_grab(channel->encoder_buffer, false);



	if (channel->user_id != -1) {

		clear_bit(channel->user_id, &dev->channel_user_ids);

		channel->user_id = -1;
@@ -2532,6 +2542,8 @@ static int allegro_create_channel(struct allegro_channel *channel) 
	v4l2_ctrl_grab(channel->mpeg_video_cpb_size, true);

	v4l2_ctrl_grab(channel->mpeg_video_gop_size, true);



	v4l2_ctrl_grab(channel->encoder_buffer, true);



	reinit_completion(&channel->completion);

	allegro_mcu_send_create_channel(dev, channel);

	timeout = wait_for_completion_timeout(&channel->completion,
@@ -2915,6 +2927,10 @@ static int allegro_try_ctrl(struct v4l2_ctrl *ctrl) 
	case V4L2_CID_MPEG_VIDEO_BITRATE_MODE:

		allegro_clamp_bitrate(channel, ctrl);

		break;

	case V4L2_CID_USER_ALLEGRO_ENCODER_BUFFER:

		if (!channel->dev->has_encoder_buffer)

			ctrl->val = 0;

		break;

	}



	return 0;
@@ -2955,6 +2971,16 @@ static const struct v4l2_ctrl_ops allegro_ctrl_ops = { 
	.s_ctrl = allegro_s_ctrl,

};



static const struct v4l2_ctrl_config allegro_encoder_buffer_ctrl_config = {

	.id = V4L2_CID_USER_ALLEGRO_ENCODER_BUFFER,

	.name = "Encoder Buffer Enable",

	.type = V4L2_CTRL_TYPE_BOOLEAN,

	.min = 0,

	.max = 1,

	.step = 1,

	.def = 1,

};



static int allegro_open(struct file *file)

{

	struct video_device *vdev = video_devdata(file);
@@ -3106,6 +3132,8 @@ static int allegro_open(struct file *file) 
			V4L2_CID_MPEG_VIDEO_GOP_SIZE,

			0, ALLEGRO_GOP_SIZE_MAX,

			1, ALLEGRO_GOP_SIZE_DEFAULT);

	channel->encoder_buffer = v4l2_ctrl_new_custom(handler,

			&allegro_encoder_buffer_ctrl_config, NULL);

	v4l2_ctrl_new_std(handler,

			  &allegro_ctrl_ops,

			  V4L2_CID_MIN_BUFFERS_FOR_OUTPUT,

include/uapi/linux/v4l2-controls.h

+5 −0
Original line number Diff line number Diff line
@@ -211,6 +211,11 @@ enum v4l2_colorfx { 
 * We reserve 128 controls for this driver.

 */

#define V4L2_CID_USER_CCS_BASE			(V4L2_CID_USER_BASE + 0x10f0)

/*

 * The base for Allegro driver controls.

 * We reserve 16 controls for this driver.

 */

#define V4L2_CID_USER_ALLEGRO_BASE		(V4L2_CID_USER_BASE + 0x1170)



/* MPEG-class control IDs */

/* The MPEG controls are applicable to all codec controls