linux/sound/usb/card.h
Ricard Wanderlof e057044677 ALSA: USB-audio: Add quirk for Zoom R16/24 playback
The Zoom R16/24 have a nonstandard playback format where each isochronous
packet contains a length descriptor in the first four bytes. (Curiously,
capture data does not contain this and requires no quirk.)

The quirk involves adding the extra length descriptor whenever outgoing
isochronous packets are generated, both in pcm.c (outgoing audio) and
endpoint.c (silent data).

In order to make the quirk as unintrusive as possible, for
pcm.c:prepare_playback_urb(), the isochronous packet descriptors are
initially set up in the same way no matter if the quirk is enabled or not.
Once it is time to actually copy the data into the outgoing packet buffer
(together with the added length descriptors) the isochronous descriptors
are adjusted in order take the increased payload length into account.

For endpoint.c:prepare_silent_urb() it makes more sense to modify the
actual function, partly because the function is less complex to start with
and partly because it is not as time-critical as prepare_playback_urb()
(whose bulk is run with interrupts disabled), so the (minute) additional
time spent in the non-quirk case is motivated by the simplicity of having
a single function for all cases.

The quirk is controlled by the new tx_length_quirk member in struct
snd_usb_substream and struct snd_usb_audio, which is conveyed to pcm.c
and endpoint.c from quirks.c in a similar manner to the txfr_quirk member
in the same structs.

In contrast to txfr_quirk however, the quirk is enabled directly in
quirks.c:create_standard_audio_quirk() by checking the USB ID in that
function. Another option would be to introduce a new
QUIRK_AUDIO_ZOOM_INTERFACE or somesuch, which would have made the quirk
very plain to see in the quirk table, but it was felt that the additional
code needed to implement it this way would just make the implementation
more complex with no real gain.

Tested with a Zoom R16, both by doing capture and playback separately
using arecord and aplay (8 channel capture and 2 channel playback,
respectively), as well as capture and playback together using Ardour, as
well as Audacity and Qtractor together with jackd.

The R24 is reportedly compatible with the R16 when used as an audio
interface. Both devices share the same USB ID and have the same number of
inputs (8) and outputs (2). Therefore "R16/24" is mentioned throughout the
patch.

Regression tested using an Edirol UA-5 in both class compliant (16-bit)
and "advanced" (24 bit, forces the use of quirks) modes.

Signed-off-by: Ricard Wanderlof <ricardw@axis.com>
Tested-by: Panu Matilainen <pmatilai@laiskiainen.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-10-19 12:38:09 +02:00

171 lines
6.6 KiB
C

#ifndef __USBAUDIO_CARD_H
#define __USBAUDIO_CARD_H
#define MAX_NR_RATES 1024
#define MAX_PACKS 6 /* per URB */
#define MAX_PACKS_HS (MAX_PACKS * 8) /* in high speed mode */
#define MAX_URBS 12
#define SYNC_URBS 4 /* always four urbs for sync */
#define MAX_QUEUE 18 /* try not to exceed this queue length, in ms */
struct audioformat {
struct list_head list;
u64 formats; /* ALSA format bits */
unsigned int channels; /* # channels */
unsigned int fmt_type; /* USB audio format type (1-3) */
unsigned int frame_size; /* samples per frame for non-audio */
int iface; /* interface number */
unsigned char altsetting; /* corresponding alternate setting */
unsigned char altset_idx; /* array index of altenate setting */
unsigned char attributes; /* corresponding attributes of cs endpoint */
unsigned char endpoint; /* endpoint */
unsigned char ep_attr; /* endpoint attributes */
unsigned char datainterval; /* log_2 of data packet interval */
unsigned char protocol; /* UAC_VERSION_1/2 */
unsigned int maxpacksize; /* max. packet size */
unsigned int rates; /* rate bitmasks */
unsigned int rate_min, rate_max; /* min/max rates */
unsigned int nr_rates; /* number of rate table entries */
unsigned int *rate_table; /* rate table */
unsigned char clock; /* associated clock */
struct snd_pcm_chmap_elem *chmap; /* (optional) channel map */
bool dsd_dop; /* add DOP headers in case of DSD samples */
bool dsd_bitrev; /* reverse the bits of each DSD sample */
};
struct snd_usb_substream;
struct snd_usb_endpoint;
struct snd_urb_ctx {
struct urb *urb;
unsigned int buffer_size; /* size of data buffer, if data URB */
struct snd_usb_substream *subs;
struct snd_usb_endpoint *ep;
int index; /* index for urb array */
int packets; /* number of packets per urb */
int packet_size[MAX_PACKS_HS]; /* size of packets for next submission */
struct list_head ready_list;
};
struct snd_usb_endpoint {
struct snd_usb_audio *chip;
int use_count;
int ep_num; /* the referenced endpoint number */
int type; /* SND_USB_ENDPOINT_TYPE_* */
unsigned long flags;
void (*prepare_data_urb) (struct snd_usb_substream *subs,
struct urb *urb);
void (*retire_data_urb) (struct snd_usb_substream *subs,
struct urb *urb);
struct snd_usb_substream *data_subs;
struct snd_usb_endpoint *sync_master;
struct snd_usb_endpoint *sync_slave;
struct snd_urb_ctx urb[MAX_URBS];
struct snd_usb_packet_info {
uint32_t packet_size[MAX_PACKS_HS];
int packets;
} next_packet[MAX_URBS];
int next_packet_read_pos, next_packet_write_pos;
struct list_head ready_playback_urbs;
unsigned int nurbs; /* # urbs */
unsigned long active_mask; /* bitmask of active urbs */
unsigned long unlink_mask; /* bitmask of unlinked urbs */
char *syncbuf; /* sync buffer for all sync URBs */
dma_addr_t sync_dma; /* DMA address of syncbuf */
unsigned int pipe; /* the data i/o pipe */
unsigned int freqn; /* nominal sampling rate in fs/fps in Q16.16 format */
unsigned int freqm; /* momentary sampling rate in fs/fps in Q16.16 format */
int freqshift; /* how much to shift the feedback value to get Q16.16 */
unsigned int freqmax; /* maximum sampling rate, used for buffer management */
unsigned int phase; /* phase accumulator */
unsigned int maxpacksize; /* max packet size in bytes */
unsigned int maxframesize; /* max packet size in frames */
unsigned int max_urb_frames; /* max URB size in frames */
unsigned int curpacksize; /* current packet size in bytes (for capture) */
unsigned int curframesize; /* current packet size in frames (for capture) */
unsigned int syncmaxsize; /* sync endpoint packet size */
unsigned int fill_max:1; /* fill max packet size always */
unsigned int udh01_fb_quirk:1; /* corrupted feedback data */
unsigned int datainterval; /* log_2 of data packet interval */
unsigned int syncinterval; /* P for adaptive mode, 0 otherwise */
unsigned char silence_value;
unsigned int stride;
int iface, altsetting;
int skip_packets; /* quirks for devices to ignore the first n packets
in a stream */
spinlock_t lock;
struct list_head list;
};
struct snd_usb_substream {
struct snd_usb_stream *stream;
struct usb_device *dev;
struct snd_pcm_substream *pcm_substream;
int direction; /* playback or capture */
int interface; /* current interface */
int endpoint; /* assigned endpoint */
struct audioformat *cur_audiofmt; /* current audioformat pointer (for hw_params callback) */
snd_pcm_format_t pcm_format; /* current audio format (for hw_params callback) */
unsigned int channels; /* current number of channels (for hw_params callback) */
unsigned int channels_max; /* max channels in the all audiofmts */
unsigned int cur_rate; /* current rate (for hw_params callback) */
unsigned int period_bytes; /* current period bytes (for hw_params callback) */
unsigned int period_frames; /* current frames per period */
unsigned int buffer_periods; /* current periods per buffer */
unsigned int altset_idx; /* USB data format: index of alternate setting */
unsigned int txfr_quirk:1; /* allow sub-frame alignment */
unsigned int tx_length_quirk:1; /* add length specifier to transfers */
unsigned int fmt_type; /* USB audio format type (1-3) */
unsigned int pkt_offset_adj; /* Bytes to drop from beginning of packets (for non-compliant devices) */
unsigned int running: 1; /* running status */
unsigned int hwptr_done; /* processed byte position in the buffer */
unsigned int transfer_done; /* processed frames since last period update */
unsigned int frame_limit; /* limits number of packets in URB */
/* data and sync endpoints for this stream */
unsigned int ep_num; /* the endpoint number */
struct snd_usb_endpoint *data_endpoint;
struct snd_usb_endpoint *sync_endpoint;
unsigned long flags;
bool need_setup_ep; /* (re)configure EP at prepare? */
unsigned int speed; /* USB_SPEED_XXX */
u64 formats; /* format bitmasks (all or'ed) */
unsigned int num_formats; /* number of supported audio formats (list) */
struct list_head fmt_list; /* format list */
struct snd_pcm_hw_constraint_list rate_list; /* limited rates */
spinlock_t lock;
int last_frame_number; /* stored frame number */
int last_delay; /* stored delay */
struct {
int marker;
int channel;
int byte_idx;
} dsd_dop;
bool trigger_tstamp_pending_update; /* trigger timestamp being updated from initial estimate */
};
struct snd_usb_stream {
struct snd_usb_audio *chip;
struct snd_pcm *pcm;
int pcm_index;
unsigned int fmt_type; /* USB audio format type (1-3) */
struct snd_usb_substream substream[2];
struct list_head list;
};
#endif /* __USBAUDIO_CARD_H */