Takashi Iwai 29d1a873de ALSA: pcm: Introduce copy_user, copy_kernel and fill_silence ops
For supporting the explicit in-kernel copy of PCM buffer data, and
also for further code refactoring, three new PCM ops, copy_user,
copy_kernel and fill_silence, are introduced.  The old copy and
silence ops will be deprecated and removed later once when all callers
are converted.

The copy_kernel ops is the new one, and it's supposed to transfer the
PCM data from the given kernel buffer to the hardware ring-buffer (or
vice-versa depending on the stream direction), while the copy_user ops
is equivalent with the former copy ops, to transfer the data from the
user-space buffer.

The major difference of the new copy_* and fill_silence ops from the
previous ops is that the new ops take bytes instead of frames for size
and position arguments.  It has two merits: first, it allows the
callback implementation often simpler (just call directly memcpy() &
co), and second, it may unify the implementations of both interleaved
and non-interleaved cases, as we'll see in the later patch.

As of this stage, copy_kernel ops isn't referred yet, but only
copy_user is used.

Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-06-02 19:37:23 +02:00
..
2015-11-18 18:08:54 +00:00
2011-08-17 00:53:54 +09:00
2011-05-19 14:10:45 -07:00
2014-05-05 18:20:22 -07:00
2015-11-30 12:24:12 +00:00
2012-09-28 14:21:54 +01:00
2017-04-03 08:42:43 +02:00
2015-02-02 14:42:42 +01:00
2016-08-08 11:55:20 +01:00
2010-10-18 16:46:27 -07:00
2015-05-22 16:01:44 +02:00
2014-07-04 18:50:51 +01:00
2015-07-09 12:00:11 +01:00
2014-04-18 18:52:18 +01:00
2015-11-18 12:55:25 +00:00
2016-09-24 19:51:57 +01:00
2015-03-11 12:08:20 +00:00
2012-12-24 15:57:20 +00:00
2014-09-15 15:52:03 +02:00
2011-09-20 16:02:16 +01:00
2009-12-18 13:06:47 +00:00
2011-08-08 14:30:37 +09:00
2010-04-30 16:12:44 +01:00