diff options
-rw-r--r-- | include/uapi/sound/firewire.h | 70 |
1 files changed, 37 insertions, 33 deletions
diff --git a/include/uapi/sound/firewire.h b/include/uapi/sound/firewire.h index 76190a0cb069..e52a97b3ceaa 100644 --- a/include/uapi/sound/firewire.h +++ b/include/uapi/sound/firewire.h @@ -68,8 +68,8 @@ struct snd_firewire_event_tascam_control { struct snd_firewire_event_motu_register_dsp_change { unsigned int type; - __u32 count; // The number of changes. - __u32 changes[]; // Encoded event for change of register DSP. + __u32 count; /* The number of changes. */ + __u32 changes[]; /* Encoded event for change of register DSP. */ }; union snd_firewire_event { @@ -119,25 +119,27 @@ struct snd_firewire_tascam_state { __be32 data[SNDRV_FIREWIRE_TASCAM_STATE_COUNT]; }; -// In below MOTU models, software is allowed to control their DSP by accessing to registers. -// - 828mk2 -// - 896hd -// - Traveler -// - 8 pre -// - Ultralite -// - 4 pre -// - Audio Express -// -// On the other hand, the status of DSP is split into specific messages included in the sequence of -// isochronous packet. ALSA firewire-motu driver gathers the messages and allow userspace applications -// to read it via ioctl. In 828mk2, 896hd, and Traveler, hardware meter for all of physical inputs -// are put into the message, while one pair of physical outputs is selected. The selection is done by -// LSB one byte in asynchronous write quadlet transaction to 0x'ffff'f000'0b2c. -// -// I note that V3HD/V4HD uses asynchronous transaction for the purpose. The destination address is -// registered to 0x'ffff'f000'0b38 and '0b3c by asynchronous write quadlet request. The size of -// message differs between 23 and 51 quadlets. For the case, the number of mixer bus can be extended -// up to 12. +/* + * In below MOTU models, software is allowed to control their DSP by accessing to registers. + * - 828mk2 + * - 896hd + * - Traveler + * - 8 pre + * - Ultralite + * - 4 pre + * - Audio Express + * + * On the other hand, the status of DSP is split into specific messages included in the sequence of + * isochronous packet. ALSA firewire-motu driver gathers the messages and allow userspace applications + * to read it via ioctl. In 828mk2, 896hd, and Traveler, hardware meter for all of physical inputs + * are put into the message, while one pair of physical outputs is selected. The selection is done by + * LSB one byte in asynchronous write quadlet transaction to 0x'ffff'f000'0b2c. + * + * I note that V3HD/V4HD uses asynchronous transaction for the purpose. The destination address is + * registered to 0x'ffff'f000'0b38 and '0b3c by asynchronous write quadlet request. The size of + * message differs between 23 and 51 quadlets. For the case, the number of mixer bus can be extended + * up to 12. + */ #define SNDRV_FIREWIRE_MOTU_REGISTER_DSP_METER_COUNT 40 @@ -219,18 +221,20 @@ struct snd_firewire_motu_register_dsp_parameter { __u8 reserved[64]; }; -// In below MOTU models, software is allowed to control their DSP by command in frame of -// asynchronous transaction to 0x'ffff'0001'0000: -// -// - 828 mk3 (FireWire only and Hybrid) -// - 896 mk3 (FireWire only and Hybrid) -// - Ultralite mk3 (FireWire only and Hybrid) -// - Traveler mk3 -// - Track 16 -// -// On the other hand, the states of hardware meter is split into specific messages included in the -// sequence of isochronous packet. ALSA firewire-motu driver gathers the message and allow userspace -// application to read it via ioctl. +/* + * In below MOTU models, software is allowed to control their DSP by command in frame of + * asynchronous transaction to 0x'ffff'0001'0000: + * + * - 828 mk3 (FireWire only and Hybrid) + * - 896 mk3 (FireWire only and Hybrid) + * - Ultralite mk3 (FireWire only and Hybrid) + * - Traveler mk3 + * - Track 16 + * + * On the other hand, the states of hardware meter is split into specific messages included in the + * sequence of isochronous packet. ALSA firewire-motu driver gathers the message and allow userspace + * application to read it via ioctl. + */ #define SNDRV_FIREWIRE_MOTU_COMMAND_DSP_METER_COUNT 400 |