diff options
Diffstat (limited to 'drivers/staging/media/allegro-dvt/allegro-core.c')
| -rw-r--r-- | drivers/staging/media/allegro-dvt/allegro-core.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c index 3b2e970c13ac..ab17e850bd1f 100644 --- a/drivers/staging/media/allegro-dvt/allegro-core.c +++ b/drivers/staging/media/allegro-dvt/allegro-core.c @@ -5,6 +5,7 @@ * Allegro DVT video encoder driver */ +#include <linux/bits.h> #include <linux/firmware.h> #include <linux/interrupt.h> #include <linux/io.h> @@ -1053,6 +1054,22 @@ v4l2_bitrate_mode_to_mcu_mode(enum v4l2_mpeg_video_bitrate_mode mode) } } +static u32 v4l2_cpb_size_to_mcu(unsigned int cpb_size, unsigned int bitrate) +{ + unsigned int cpb_size_kbit; + unsigned int bitrate_kbps; + + /* + * The mcu expects the CPB size in units of a 90 kHz clock, but the + * channel follows the V4L2_CID_MPEG_VIDEO_H264_CPB_SIZE and stores + * the CPB size in kilobytes. + */ + cpb_size_kbit = cpb_size * BITS_PER_BYTE; + bitrate_kbps = bitrate / 1000; + + return (cpb_size_kbit * 90000) / bitrate_kbps; +} + static int allegro_mcu_send_create_channel(struct allegro_dev *dev, struct allegro_channel *channel) { @@ -1094,12 +1111,10 @@ static int allegro_mcu_send_create_channel(struct allegro_dev *dev, msg.rate_control_mode = v4l2_bitrate_mode_to_mcu_mode(channel->bitrate_mode); + msg.cpb_size = v4l2_cpb_size_to_mcu(channel->cpb_size, + channel->bitrate_peak); /* Shall be ]0;cpb_size in 90 kHz units]. Use maximum value. */ - msg.initial_rem_delay = - ((channel->cpb_size * 1000) / channel->bitrate_peak) * 90000; - /* Encoder expects cpb_size in units of a 90 kHz clock. */ - msg.cpb_size = - ((channel->cpb_size * 1000) / channel->bitrate_peak) * 90000; + msg.initial_rem_delay = msg.cpb_size; msg.framerate = 25; msg.clk_ratio = 1000; msg.target_bitrate = channel->bitrate; |