License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 15:07:57 +01:00
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/* SPDX-License-Identifier: GPL-2.0 */
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2010-03-04 19:46:13 +01:00
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#ifndef __USBAUDIO_CARD_H
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#define __USBAUDIO_CARD_H
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2012-02-14 11:18:48 +01:00
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#define MAX_NR_RATES 1024
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ALSA: improve buffer size computations for USB PCM audio
This patch changes the way URBs are allocated and their sizes are
determined for PCM playback in the snd-usb-audio driver. Currently
the driver allocates too few URBs for endpoints that don't use
implicit sync, making underruns more likely to occur. This may be a
holdover from before I/O delays could be measured accurately; in any
case, it is no longer necessary.
The patch allocates as many URBs as possible, subject to four
limitations:
The total number of URBs for the endpoint is not allowed to
exceed MAX_URBS (which the patch increases from 8 to 12).
The total number of packets per URB is not allowed to exceed
MAX_PACKS (or MAX_PACKS_HS for high-speed devices), which is
decreased from 20 to 6.
The total duration of queued data is not allowed to exceed
MAX_QUEUE, which is decreased from 24 ms to 18 ms.
The total number of ALSA frames in the output queue is not
allowed to exceed the ALSA buffer size.
The last requirement is the hardest to implement. Currently the
number of URBs needed to fill a buffer cannot be determined in
advance, because a buffer contains a fixed number of frames whereas
the number of frames in an URB varies to match shifts in the device's
clock rate. To solve this problem, the patch changes the logic for
deciding how many packets an URB should contain. Rather than using as
many as possible without exceeding an ALSA period boundary, now the
driver uses only as many packets as needed to transfer a predetermined
number of frames. As a result, unless the device's clock has an
exceedingly variable rate, the number of URBs making up each period
(and hence each buffer) will remain constant.
The overall effect of the patch is that playback works better in
low-latency settings. The user can still specify values for
frames/period and periods/buffer that exceed the capabilities of the
hardware, of course. But for values that are within those
capabilities, the performance will be improved. For example, testing
shows that a high-speed device can handle 32 frames/period and 3
periods/buffer at 48 KHz, whereas the current driver starts to get
glitchy at 64 frames/period and 2 periods/buffer.
A side effect of these changes is that the "nrpacks" module parameter
is no longer used. The patch removes it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Daniel Mack <zonque@gmail.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-09-24 21:51:58 +02:00
|
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#define MAX_PACKS 6 /* per URB */
|
2010-03-04 19:46:13 +01:00
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#define MAX_PACKS_HS (MAX_PACKS * 8) /* in high speed mode */
|
ALSA: improve buffer size computations for USB PCM audio
This patch changes the way URBs are allocated and their sizes are
determined for PCM playback in the snd-usb-audio driver. Currently
the driver allocates too few URBs for endpoints that don't use
implicit sync, making underruns more likely to occur. This may be a
holdover from before I/O delays could be measured accurately; in any
case, it is no longer necessary.
The patch allocates as many URBs as possible, subject to four
limitations:
The total number of URBs for the endpoint is not allowed to
exceed MAX_URBS (which the patch increases from 8 to 12).
The total number of packets per URB is not allowed to exceed
MAX_PACKS (or MAX_PACKS_HS for high-speed devices), which is
decreased from 20 to 6.
The total duration of queued data is not allowed to exceed
MAX_QUEUE, which is decreased from 24 ms to 18 ms.
The total number of ALSA frames in the output queue is not
allowed to exceed the ALSA buffer size.
The last requirement is the hardest to implement. Currently the
number of URBs needed to fill a buffer cannot be determined in
advance, because a buffer contains a fixed number of frames whereas
the number of frames in an URB varies to match shifts in the device's
clock rate. To solve this problem, the patch changes the logic for
deciding how many packets an URB should contain. Rather than using as
many as possible without exceeding an ALSA period boundary, now the
driver uses only as many packets as needed to transfer a predetermined
number of frames. As a result, unless the device's clock has an
exceedingly variable rate, the number of URBs making up each period
(and hence each buffer) will remain constant.
The overall effect of the patch is that playback works better in
low-latency settings. The user can still specify values for
frames/period and periods/buffer that exceed the capabilities of the
hardware, of course. But for values that are within those
capabilities, the performance will be improved. For example, testing
shows that a high-speed device can handle 32 frames/period and 3
periods/buffer at 48 KHz, whereas the current driver starts to get
glitchy at 64 frames/period and 2 periods/buffer.
A side effect of these changes is that the "nrpacks" module parameter
is no longer used. The patch removes it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Daniel Mack <zonque@gmail.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-09-24 21:51:58 +02:00
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#define MAX_URBS 12
|
2010-03-04 19:46:13 +01:00
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#define SYNC_URBS 4 /* always four urbs for sync */
|
ALSA: improve buffer size computations for USB PCM audio
This patch changes the way URBs are allocated and their sizes are
determined for PCM playback in the snd-usb-audio driver. Currently
the driver allocates too few URBs for endpoints that don't use
implicit sync, making underruns more likely to occur. This may be a
holdover from before I/O delays could be measured accurately; in any
case, it is no longer necessary.
The patch allocates as many URBs as possible, subject to four
limitations:
The total number of URBs for the endpoint is not allowed to
exceed MAX_URBS (which the patch increases from 8 to 12).
The total number of packets per URB is not allowed to exceed
MAX_PACKS (or MAX_PACKS_HS for high-speed devices), which is
decreased from 20 to 6.
The total duration of queued data is not allowed to exceed
MAX_QUEUE, which is decreased from 24 ms to 18 ms.
The total number of ALSA frames in the output queue is not
allowed to exceed the ALSA buffer size.
The last requirement is the hardest to implement. Currently the
number of URBs needed to fill a buffer cannot be determined in
advance, because a buffer contains a fixed number of frames whereas
the number of frames in an URB varies to match shifts in the device's
clock rate. To solve this problem, the patch changes the logic for
deciding how many packets an URB should contain. Rather than using as
many as possible without exceeding an ALSA period boundary, now the
driver uses only as many packets as needed to transfer a predetermined
number of frames. As a result, unless the device's clock has an
exceedingly variable rate, the number of URBs making up each period
(and hence each buffer) will remain constant.
The overall effect of the patch is that playback works better in
low-latency settings. The user can still specify values for
frames/period and periods/buffer that exceed the capabilities of the
hardware, of course. But for values that are within those
capabilities, the performance will be improved. For example, testing
shows that a high-speed device can handle 32 frames/period and 3
periods/buffer at 48 KHz, whereas the current driver starts to get
glitchy at 64 frames/period and 2 periods/buffer.
A side effect of these changes is that the "nrpacks" module parameter
is no longer used. The patch removes it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Daniel Mack <zonque@gmail.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-09-24 21:51:58 +02:00
|
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#define MAX_QUEUE 18 /* try not to exceed this queue length, in ms */
|
2010-03-04 19:46:13 +01:00
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struct audioformat {
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struct list_head list;
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2010-03-04 19:46:15 +01:00
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u64 formats; /* ALSA format bits */
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2010-03-04 19:46:13 +01:00
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unsigned int channels; /* # channels */
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unsigned int fmt_type; /* USB audio format type (1-3) */
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unsigned int frame_size; /* samples per frame for non-audio */
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int iface; /* interface number */
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unsigned char altsetting; /* corresponding alternate setting */
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unsigned char altset_idx; /* array index of altenate setting */
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unsigned char attributes; /* corresponding attributes of cs endpoint */
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unsigned char endpoint; /* endpoint */
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unsigned char ep_attr; /* endpoint attributes */
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unsigned char datainterval; /* log_2 of data packet interval */
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2013-01-31 21:39:17 +01:00
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unsigned char protocol; /* UAC_VERSION_1/2 */
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2010-03-04 19:46:13 +01:00
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unsigned int maxpacksize; /* max. packet size */
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unsigned int rates; /* rate bitmasks */
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unsigned int rate_min, rate_max; /* min/max rates */
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unsigned int nr_rates; /* number of rate table entries */
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unsigned int *rate_table; /* rate table */
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2010-05-31 14:51:31 +02:00
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unsigned char clock; /* associated clock */
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2012-11-26 16:24:02 +01:00
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struct snd_pcm_chmap_elem *chmap; /* (optional) channel map */
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2013-04-16 18:01:38 +02:00
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bool dsd_dop; /* add DOP headers in case of DSD samples */
|
2013-04-16 18:01:39 +02:00
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bool dsd_bitrev; /* reverse the bits of each DSD sample */
|
2010-03-04 19:46:13 +01:00
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};
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struct snd_usb_substream;
|
2012-04-12 13:51:11 +02:00
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struct snd_usb_endpoint;
|
2010-03-04 19:46:13 +01:00
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struct snd_urb_ctx {
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struct urb *urb;
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unsigned int buffer_size; /* size of data buffer, if data URB */
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struct snd_usb_substream *subs;
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2012-04-12 13:51:11 +02:00
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struct snd_usb_endpoint *ep;
|
2010-03-04 19:46:13 +01:00
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int index; /* index for urb array */
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int packets; /* number of packets per urb */
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2012-04-12 13:51:11 +02:00
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int packet_size[MAX_PACKS_HS]; /* size of packets for next submission */
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struct list_head ready_list;
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2010-03-04 19:46:13 +01:00
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};
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2012-04-12 13:51:11 +02:00
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struct snd_usb_endpoint {
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struct snd_usb_audio *chip;
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int use_count;
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int ep_num; /* the referenced endpoint number */
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int type; /* SND_USB_ENDPOINT_TYPE_* */
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unsigned long flags;
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void (*prepare_data_urb) (struct snd_usb_substream *subs,
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struct urb *urb);
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void (*retire_data_urb) (struct snd_usb_substream *subs,
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struct urb *urb);
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struct snd_usb_substream *data_subs;
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struct snd_usb_endpoint *sync_master;
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struct snd_usb_endpoint *sync_slave;
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struct snd_urb_ctx urb[MAX_URBS];
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struct snd_usb_packet_info {
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uint32_t packet_size[MAX_PACKS_HS];
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int packets;
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} next_packet[MAX_URBS];
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int next_packet_read_pos, next_packet_write_pos;
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struct list_head ready_playback_urbs;
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unsigned int nurbs; /* # urbs */
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unsigned long active_mask; /* bitmask of active urbs */
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unsigned long unlink_mask; /* bitmask of unlinked urbs */
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char *syncbuf; /* sync buffer for all sync URBs */
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dma_addr_t sync_dma; /* DMA address of syncbuf */
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unsigned int pipe; /* the data i/o pipe */
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unsigned int freqn; /* nominal sampling rate in fs/fps in Q16.16 format */
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unsigned int freqm; /* momentary sampling rate in fs/fps in Q16.16 format */
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int freqshift; /* how much to shift the feedback value to get Q16.16 */
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unsigned int freqmax; /* maximum sampling rate, used for buffer management */
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unsigned int phase; /* phase accumulator */
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unsigned int maxpacksize; /* max packet size in bytes */
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unsigned int maxframesize; /* max packet size in frames */
|
ALSA: improve buffer size computations for USB PCM audio
This patch changes the way URBs are allocated and their sizes are
determined for PCM playback in the snd-usb-audio driver. Currently
the driver allocates too few URBs for endpoints that don't use
implicit sync, making underruns more likely to occur. This may be a
holdover from before I/O delays could be measured accurately; in any
case, it is no longer necessary.
The patch allocates as many URBs as possible, subject to four
limitations:
The total number of URBs for the endpoint is not allowed to
exceed MAX_URBS (which the patch increases from 8 to 12).
The total number of packets per URB is not allowed to exceed
MAX_PACKS (or MAX_PACKS_HS for high-speed devices), which is
decreased from 20 to 6.
The total duration of queued data is not allowed to exceed
MAX_QUEUE, which is decreased from 24 ms to 18 ms.
The total number of ALSA frames in the output queue is not
allowed to exceed the ALSA buffer size.
The last requirement is the hardest to implement. Currently the
number of URBs needed to fill a buffer cannot be determined in
advance, because a buffer contains a fixed number of frames whereas
the number of frames in an URB varies to match shifts in the device's
clock rate. To solve this problem, the patch changes the logic for
deciding how many packets an URB should contain. Rather than using as
many as possible without exceeding an ALSA period boundary, now the
driver uses only as many packets as needed to transfer a predetermined
number of frames. As a result, unless the device's clock has an
exceedingly variable rate, the number of URBs making up each period
(and hence each buffer) will remain constant.
The overall effect of the patch is that playback works better in
low-latency settings. The user can still specify values for
frames/period and periods/buffer that exceed the capabilities of the
hardware, of course. But for values that are within those
capabilities, the performance will be improved. For example, testing
shows that a high-speed device can handle 32 frames/period and 3
periods/buffer at 48 KHz, whereas the current driver starts to get
glitchy at 64 frames/period and 2 periods/buffer.
A side effect of these changes is that the "nrpacks" module parameter
is no longer used. The patch removes it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Daniel Mack <zonque@gmail.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-09-24 21:51:58 +02:00
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unsigned int max_urb_frames; /* max URB size in frames */
|
2012-04-12 13:51:11 +02:00
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unsigned int curpacksize; /* current packet size in bytes (for capture) */
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unsigned int curframesize; /* current packet size in frames (for capture) */
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unsigned int syncmaxsize; /* sync endpoint packet size */
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unsigned int fill_max:1; /* fill max packet size always */
|
2016-08-22 08:53:37 +02:00
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unsigned int tenor_fb_quirk:1; /* corrupted feedback data */
|
2012-04-12 13:51:11 +02:00
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unsigned int datainterval; /* log_2 of data packet interval */
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unsigned int syncinterval; /* P for adaptive mode, 0 otherwise */
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unsigned char silence_value;
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unsigned int stride;
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2013-10-06 22:31:13 +02:00
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int iface, altsetting;
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2012-09-04 10:23:07 +02:00
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int skip_packets; /* quirks for devices to ignore the first n packets
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in a stream */
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2012-04-12 13:51:11 +02:00
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spinlock_t lock;
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struct list_head list;
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};
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2010-03-04 19:46:13 +01:00
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struct snd_usb_substream {
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struct snd_usb_stream *stream;
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struct usb_device *dev;
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struct snd_pcm_substream *pcm_substream;
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int direction; /* playback or capture */
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int interface; /* current interface */
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int endpoint; /* assigned endpoint */
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struct audioformat *cur_audiofmt; /* current audioformat pointer (for hw_params callback) */
|
2012-09-18 18:49:48 +02:00
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snd_pcm_format_t pcm_format; /* current audio format (for hw_params callback) */
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unsigned int channels; /* current number of channels (for hw_params callback) */
|
2012-11-26 16:24:02 +01:00
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unsigned int channels_max; /* max channels in the all audiofmts */
|
2010-03-04 19:46:13 +01:00
|
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unsigned int cur_rate; /* current rate (for hw_params callback) */
|
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unsigned int period_bytes; /* current period bytes (for hw_params callback) */
|
ALSA: improve buffer size computations for USB PCM audio
This patch changes the way URBs are allocated and their sizes are
determined for PCM playback in the snd-usb-audio driver. Currently
the driver allocates too few URBs for endpoints that don't use
implicit sync, making underruns more likely to occur. This may be a
holdover from before I/O delays could be measured accurately; in any
case, it is no longer necessary.
The patch allocates as many URBs as possible, subject to four
limitations:
The total number of URBs for the endpoint is not allowed to
exceed MAX_URBS (which the patch increases from 8 to 12).
The total number of packets per URB is not allowed to exceed
MAX_PACKS (or MAX_PACKS_HS for high-speed devices), which is
decreased from 20 to 6.
The total duration of queued data is not allowed to exceed
MAX_QUEUE, which is decreased from 24 ms to 18 ms.
The total number of ALSA frames in the output queue is not
allowed to exceed the ALSA buffer size.
The last requirement is the hardest to implement. Currently the
number of URBs needed to fill a buffer cannot be determined in
advance, because a buffer contains a fixed number of frames whereas
the number of frames in an URB varies to match shifts in the device's
clock rate. To solve this problem, the patch changes the logic for
deciding how many packets an URB should contain. Rather than using as
many as possible without exceeding an ALSA period boundary, now the
driver uses only as many packets as needed to transfer a predetermined
number of frames. As a result, unless the device's clock has an
exceedingly variable rate, the number of URBs making up each period
(and hence each buffer) will remain constant.
The overall effect of the patch is that playback works better in
low-latency settings. The user can still specify values for
frames/period and periods/buffer that exceed the capabilities of the
hardware, of course. But for values that are within those
capabilities, the performance will be improved. For example, testing
shows that a high-speed device can handle 32 frames/period and 3
periods/buffer at 48 KHz, whereas the current driver starts to get
glitchy at 64 frames/period and 2 periods/buffer.
A side effect of these changes is that the "nrpacks" module parameter
is no longer used. The patch removes it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Daniel Mack <zonque@gmail.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-09-24 21:51:58 +02:00
|
|
|
unsigned int period_frames; /* current frames per period */
|
|
|
|
unsigned int buffer_periods; /* current periods per buffer */
|
2010-03-04 19:46:14 +01:00
|
|
|
unsigned int altset_idx; /* USB data format: index of alternate setting */
|
2010-03-04 19:46:13 +01:00
|
|
|
unsigned int txfr_quirk:1; /* allow sub-frame alignment */
|
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 08:52:53 +02:00
|
|
|
unsigned int tx_length_quirk:1; /* add length specifier to transfers */
|
2010-03-04 19:46:13 +01:00
|
|
|
unsigned int fmt_type; /* USB audio format type (1-3) */
|
2013-04-13 05:33:59 +02:00
|
|
|
unsigned int pkt_offset_adj; /* Bytes to drop from beginning of packets (for non-compliant devices) */
|
2010-03-04 19:46:13 +01:00
|
|
|
|
|
|
|
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 */
|
ALSA: improve buffer size computations for USB PCM audio
This patch changes the way URBs are allocated and their sizes are
determined for PCM playback in the snd-usb-audio driver. Currently
the driver allocates too few URBs for endpoints that don't use
implicit sync, making underruns more likely to occur. This may be a
holdover from before I/O delays could be measured accurately; in any
case, it is no longer necessary.
The patch allocates as many URBs as possible, subject to four
limitations:
The total number of URBs for the endpoint is not allowed to
exceed MAX_URBS (which the patch increases from 8 to 12).
The total number of packets per URB is not allowed to exceed
MAX_PACKS (or MAX_PACKS_HS for high-speed devices), which is
decreased from 20 to 6.
The total duration of queued data is not allowed to exceed
MAX_QUEUE, which is decreased from 24 ms to 18 ms.
The total number of ALSA frames in the output queue is not
allowed to exceed the ALSA buffer size.
The last requirement is the hardest to implement. Currently the
number of URBs needed to fill a buffer cannot be determined in
advance, because a buffer contains a fixed number of frames whereas
the number of frames in an URB varies to match shifts in the device's
clock rate. To solve this problem, the patch changes the logic for
deciding how many packets an URB should contain. Rather than using as
many as possible without exceeding an ALSA period boundary, now the
driver uses only as many packets as needed to transfer a predetermined
number of frames. As a result, unless the device's clock has an
exceedingly variable rate, the number of URBs making up each period
(and hence each buffer) will remain constant.
The overall effect of the patch is that playback works better in
low-latency settings. The user can still specify values for
frames/period and periods/buffer that exceed the capabilities of the
hardware, of course. But for values that are within those
capabilities, the performance will be improved. For example, testing
shows that a high-speed device can handle 32 frames/period and 3
periods/buffer at 48 KHz, whereas the current driver starts to get
glitchy at 64 frames/period and 2 periods/buffer.
A side effect of these changes is that the "nrpacks" module parameter
is no longer used. The patch removes it.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
CC: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Daniel Mack <zonque@gmail.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2013-09-24 21:51:58 +02:00
|
|
|
unsigned int frame_limit; /* limits number of packets in URB */
|
2010-03-04 19:46:13 +01:00
|
|
|
|
2012-04-12 13:51:12 +02:00
|
|
|
/* data and sync endpoints for this stream */
|
2012-06-08 09:01:37 +02:00
|
|
|
unsigned int ep_num; /* the endpoint number */
|
2012-04-12 13:51:12 +02:00
|
|
|
struct snd_usb_endpoint *data_endpoint;
|
|
|
|
struct snd_usb_endpoint *sync_endpoint;
|
|
|
|
unsigned long flags;
|
2012-09-18 14:49:31 +02:00
|
|
|
bool need_setup_ep; /* (re)configure EP at prepare? */
|
2012-10-12 15:12:55 +02:00
|
|
|
unsigned int speed; /* USB_SPEED_XXX */
|
2010-03-04 19:46:13 +01:00
|
|
|
|
|
|
|
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;
|
|
|
|
|
2011-09-07 02:15:34 +02:00
|
|
|
int last_frame_number; /* stored frame number */
|
|
|
|
int last_delay; /* stored delay */
|
2013-04-16 18:01:38 +02:00
|
|
|
|
|
|
|
struct {
|
|
|
|
int marker;
|
|
|
|
int channel;
|
|
|
|
int byte_idx;
|
|
|
|
} dsd_dop;
|
2015-02-06 22:55:53 +01:00
|
|
|
|
|
|
|
bool trigger_tstamp_pending_update; /* trigger timestamp being updated from initial estimate */
|
2010-03-04 19:46:13 +01:00
|
|
|
};
|
|
|
|
|
|
|
|
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 */
|