OpenCloudOS-Kernel/sound/firewire/fireface/amdtp-ff.c

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// SPDX-License-Identifier: GPL-2.0-only
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
/*
* amdtp-ff.c - a part of driver for RME Fireface series
*
* Copyright (c) 2015-2017 Takashi Sakamoto
*/
#include <sound/pcm.h>
#include "ff.h"
struct amdtp_ff {
unsigned int pcm_channels;
};
int amdtp_ff_set_parameters(struct amdtp_stream *s, unsigned int rate,
unsigned int pcm_channels)
{
struct amdtp_ff *p = s->protocol;
unsigned int data_channels;
if (amdtp_stream_running(s))
return -EBUSY;
p->pcm_channels = pcm_channels;
data_channels = pcm_channels;
return amdtp_stream_set_parameters(s, rate, data_channels);
}
static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
__le32 *buffer, unsigned int frames,
unsigned int pcm_frames)
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
{
struct amdtp_ff *p = s->protocol;
unsigned int channels = p->pcm_channels;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int pcm_buffer_pointer;
int remaining_frames;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
const u32 *src;
int i, c;
pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
pcm_buffer_pointer %= runtime->buffer_size;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
src = (void *)runtime->dma_area +
frames_to_bytes(runtime, pcm_buffer_pointer);
remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
buffer[c] = cpu_to_le32(*src);
src++;
}
buffer += s->data_block_quadlets;
if (--remaining_frames == 0)
src = (void *)runtime->dma_area;
}
}
static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
__le32 *buffer, unsigned int frames,
unsigned int pcm_frames)
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
{
struct amdtp_ff *p = s->protocol;
unsigned int channels = p->pcm_channels;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int pcm_buffer_pointer;
int remaining_frames;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
u32 *dst;
int i, c;
pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
pcm_buffer_pointer %= runtime->buffer_size;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
dst = (void *)runtime->dma_area +
frames_to_bytes(runtime, pcm_buffer_pointer);
remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
*dst = le32_to_cpu(buffer[c]) & 0xffffff00;
dst++;
}
buffer += s->data_block_quadlets;
if (--remaining_frames == 0)
dst = (void *)runtime->dma_area;
}
}
static void write_pcm_silence(struct amdtp_stream *s,
__le32 *buffer, unsigned int frames)
{
struct amdtp_ff *p = s->protocol;
unsigned int i, c, channels = p->pcm_channels;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c)
buffer[c] = cpu_to_le32(0x00000000);
buffer += s->data_block_quadlets;
}
}
int amdtp_ff_add_pcm_hw_constraints(struct amdtp_stream *s,
struct snd_pcm_runtime *runtime)
{
int err;
err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
if (err < 0)
return err;
return amdtp_stream_add_pcm_hw_constraints(s, runtime);
}
static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
const struct pkt_desc *descs,
unsigned int packets,
struct snd_pcm_substream *pcm)
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
{
unsigned int pcm_frames = 0;
int i;
for (i = 0; i < packets; ++i) {
const struct pkt_desc *desc = descs + i;
__le32 *buf = (__le32 *)desc->ctx_payload;
unsigned int data_blocks = desc->data_blocks;
if (pcm) {
write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
pcm_frames += data_blocks;
} else {
write_pcm_silence(s, buf, data_blocks);
}
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
}
return pcm_frames;
}
static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
const struct pkt_desc *descs,
unsigned int packets,
struct snd_pcm_substream *pcm)
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
{
unsigned int pcm_frames = 0;
int i;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
for (i = 0; i < packets; ++i) {
const struct pkt_desc *desc = descs + i;
__le32 *buf = (__le32 *)desc->ctx_payload;
unsigned int data_blocks = desc->data_blocks;
if (pcm) {
read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
pcm_frames += data_blocks;
}
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
}
return pcm_frames;
}
int amdtp_ff_init(struct amdtp_stream *s, struct fw_unit *unit,
enum amdtp_stream_direction dir)
{
amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
if (dir == AMDTP_IN_STREAM)
process_ctx_payloads = process_ir_ctx_payloads;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
else
process_ctx_payloads = process_it_ctx_payloads;
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
return amdtp_stream_init(s, unit, dir, CIP_NO_HEADER, 0,
process_ctx_payloads, sizeof(struct amdtp_ff));
ALSA: fireface: add unique data processing layer As long as investigating Fireface 400, format of payload of each isochronous packet is not IEC 61883-1/6, thus its format of data block is not AM824. The remarkable points of the format are: * The payload just consists of some data channels of quadlet size without CIP header. * Each data channels includes data aligned to little endian order. * One data channel consists of two parts; 8 bit ancillary field and 24 bit PCM frame. Due to lack of CIP headers, rx/tx packets include no CIP headers and different way to check packet discontinuity. For tx packet, the ancillary field is used for counter. However, the way of counting is different depending on positions of data channels. At 44.1 kHz, ancillary field in: * 1st/6th/9th/10th/14th/17th data channels: not used for this purpose. * 2nd/18th data channels: incremented every data block (0x00-0xff). * 3rd/4th/5th/11th/12th/13th data channels: incremented every 256 data blocks (0x00-0x07). * 7th/8th/15th/16th data channels: incremented per the number of data blocks in a packet. The increment can occur per packet (0x00-0xff). For tx packet, tag of each isochronous packet is used for this purpose. The value of tag cyclically changes between 0, 1, 2 and 3 in this order. The interval is different depending on sampling transmission frequency. At 44.1/48.0 kHz, it's 256 data blocks. At 88.2 kHz, it's 96 data blocks. The number of data blocks in tx packet is exactly the same as SYT_INTERVAL. There's no empty packet or no-data packet, thus the throughput is not 8,000 packets per sec. On the other hand, the one in rx packet is 8,000 packets per sec, thus the number of data blocks is different between each packet, depending on sampling transmission frequency: * 44.1 kHz: 5 or 6 * 48.0 kHz: 5 or 6 or 7 * 88.2 kHz: 10 or 11 or 12 This commit adds data processing layer to satisfy the above specification in a policy of 'best effort'. Although PCM frames are handled for intermediate buffer to user space, the ancillary data is not handled at all to reduce CPU usage, thus counter is not checked. 0 is always used for tag of isochronous packet. Furthermore, the packet streaming layer is responsible for calculation of the number of data blocks for each packet, thus it's not exactly the same sequence from the above observation. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-31 21:06:08 +08:00
}