remap: Don't use PA_VOLUME_NORM

remapping operates on channel contributions, not volumes

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Rename pa_init_remap() to pa_init_remap_func()

pa_init_remap_func() only sets the appropriate remapping function, it
does not initialize the pa_remap struct

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Refactor channel remap table computation calc_map_table()

Make the resampler argument const, and pass explicit remap
structure argument

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Make resampler's remap structure more self-contained

Initialization of the remap structure now happens in one place

Rename calc_map_table() to setup_remap(), copy sample format and
channel specs; the remap structure is initialized when we know the
work sample format of the resampler

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Split remapping functions into s16 and float implementation

The sample format is known when the remap structure is initialized,
no runtime decision needed.

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Use float constant instead of double

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Add helper function to setup channel arrangement information

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Cleanup remap function selection, add pa_set_remap_func() helper

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Change remapping function argument type from void to int16_t / float as appropriate

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Add (optional) state to remap struct

State can be used by remap function implementations to
speed up the remapping, e.g. by precomputing things or
even by generating specialized code for a specific channel
remapping task

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Add special remapping case which just re-arranges channels

Input channels may just be copied to output channels, no mixing; this
avoids the generic (slow) matrix remapping code in cases where channels
are dropped or reordered.
This makes use of the remap struct state introduced earlier.

on Intel Core i7-870 @ 2.93 GHz (GCC 4.6, 64-bit):

Checking special remap (s16, stereo rearrange)
func: 126117 usec (avg: 1261.17, min = 1150, max = 2111, stddev = 117.332).
orig: 190509 usec (avg: 1905.09, min = 1807, max = 2402, stddev = 100.984).
Checking special remap (float, stereo rearrange)
func: 194329 usec (avg: 1943.29, min = 1876, max = 2127, stddev = 64.3486).
orig: 205263 usec (avg: 2052.63, min = 2005, max = 2452, stddev = 70.177).
Checking special remap (s16, 4-channel rearrange)
func: 278754 usec (avg: 2787.54, min = 2719, max = 3093, stddev = 78.22).
orig: 383885 usec (avg: 3838.85, min = 3634, max = 4121, stddev = 128.522).
Checking special remap (float, 4-channel rearrange)
func: 312429 usec (avg: 3124.29, min = 3017, max = 3498, stddev = 120.127).
orig: 388198 usec (avg: 3881.98, min = 3768, max = 4655, stddev = 138.441).

on ARM Cortex-A8 (TI OMAP3 DM3730 @ 1GHz) (Linaro GCC 4.6):

Checking special remap (s16, stereo rearrange)
func: 1204647 usec (avg: 12046.5, min = 10406, max = 25451, stddev = 2491.9).
orig: 1660311 usec (avg: 16603.1, min = 14740, max = 20416, stddev = 1708.07).
Checking special remap (float, stereo rearrange)
func: 1391392 usec (avg: 13913.9, min = 12207, max = 28260, stddev = 2238.12).
orig: 9246707 usec (avg: 92467.1, min = 87525, max = 125611, stddev = 5494.64).
Checking special remap (s16, 4-channel rearrange)
func: 2540225 usec (avg: 25402.2, min = 16937, max = 68268, stddev = 10786.7).
orig: 3319852 usec (avg: 33198.5, min = 29571, max = 36957, stddev = 1250.39).
Checking special remap (float, 4-channel rearrange)
func: 3024414 usec (avg: 30244.1, min = 26153, max = 58105, stddev = 4506.01).
orig: 12643624 usec (avg: 126436, min = 120575, max = 159088, stddev = 5519.28).

benchmark code will be posted as follow-up patches

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
remap: Add stereo to mono and 4-channel special case remapping

The generic matrix remapping is rather inefficient; special-case code
improves performance by 3x easily.

v4: split into s16 and float code, 4-channel remapping
v3: fix remap_mono_to_stereo_c(), use assignment
v2: use consistent array addressing

on Intel Core i7-870 @ 2.93 GHz (GCC 4.6, 64-bit):

Checking special remap (float, mono->stereo)
func: 70392 usec (avg: 703.92, min = 583, max = 1879, stddev = 295.192).
orig: 193042 usec (avg: 1930.42, min = 1457, max = 2269, stddev = 89.9045).
Checking special remap (float, mono->4-channel)
func: 118408 usec (avg: 1184.08, min = 1151, max = 1454, stddev = 57.1244).
orig: 380074 usec (avg: 3800.74, min = 3740, max = 4180, stddev = 96.3389).
Checking special remap (s16, mono->stereo)
func: 60574 usec (avg: 605.74, min = 582, max = 659, stddev = 20.7681).
orig: 188262 usec (avg: 1882.62, min = 1804, max = 2167, stddev = 79.17).
Checking special remap (s16, mono->4-channel)
func: 120331 usec (avg: 1203.31, min = 1151, max = 1429, stddev = 55.2863).
orig: 376028 usec (avg: 3760.28, min = 3609, max = 4096, stddev = 122.043).
Checking special remap (float, stereo->mono)
func: 61408 usec (avg: 614.08, min = 580, max = 867, stddev = 50.933).
orig: 186484 usec (avg: 1864.84, min = 1808, max = 2121, stddev = 65.3967).
Checking special remap (float, 4-channel->mono)
func: 118101 usec (avg: 1181.01, min = 1157, max = 1383, stddev = 36.4474).
orig: 365191 usec (avg: 3651.91, min = 3540, max = 4083, stddev = 117.509).
Checking special remap (s16, stereo->mono)
func: 82908 usec (avg: 829.08, min = 795, max = 953, stddev = 33.3409).
orig: 182565 usec (avg: 1825.65, min = 1774, max = 2117, stddev = 65.5401).
Checking special remap (s16, 4-channel->mono)
func: 132025 usec (avg: 1320.25, min = 1284, max = 1509, stddev = 47.0133).
orig: 363347 usec (avg: 3633.47, min = 3560, max = 4012, stddev = 111.259).

on ARM Cortex-A8 (TI OMAP3 DM3730 @ 1GHz) (Linaro GCC 4.6):

Checking special remap (float, mono->stereo)
func: 1213562 usec (avg: 12135.6, min = 4669, max = 16266, stddev = 2067.64).
orig: 9251927 usec (avg: 92519.3, min = 87372, max = 134216, stddev = 5965.79).
Checking special remap (float, mono->4-channel)
func: 2479550 usec (avg: 24795.5, min = 7507, max = 29358, stddev = 2690.16).
orig: 13186133 usec (avg: 131861, min = 119843, max = 263855, stddev = 27309).
Checking special remap (s16, mono->stereo)
func: 471894 usec (avg: 4718.94, min = 4058, max = 9583, stddev = 1302.7).
orig: 1673826 usec (avg: 16738.3, min = 14679, max = 31342, stddev = 2271.67).
Checking special remap (s16, mono->4-channel)
func: 869508 usec (avg: 8695.08, min = 7019, max = 19165, stddev = 1866.94).
orig: 3317020 usec (avg: 33170.2, min = 29327, max = 47577, stddev = 2029.11).
Checking special remap (float, stereo->mono)
func: 4405182 usec (avg: 44051.8, min = 41443, max = 77912, stddev = 4160.54).
orig: 13245064 usec (avg: 132451, min = 125244, max = 182282, stddev = 8543.93).
Checking special remap (float, 4-channel->mono)
func: 8607974 usec (avg: 86079.7, min = 81909, max = 116608, stddev = 4311.52).
orig: 26326036 usec (avg: 263260, min = 255097, max = 312928, stddev = 10111.5).
Checking special remap (s16, stereo->mono)
func: 1209135 usec (avg: 12091.4, min = 10742, max = 16632, stddev = 1633.88).
orig: 3081515 usec (avg: 30815.2, min = 27008, max = 50537, stddev = 3124.35).
Checking special remap (s16, 4-channel->mono)
func: 1653868 usec (avg: 16538.7, min = 14648, max = 20721, stddev = 1834.52).
orig: 6017854 usec (avg: 60178.5, min = 56061, max = 89569, stddev = 4052.86).

benchmark code will be posted as follow-up patches

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
sink, source: Assign to reference_volume from only one place

Forcing all reference volume changes to go through
set_reference_volume_direct() makes it easier to check where the
reference volume is changed, and it also allows us to have only one
place where notifications for changed reference volume are sent.
sink-input, source-output: Assign to volume from only one place

Forcing all volume changes to go through set_volume_direct() makes
it easier to check where the stream volume is changed, and it also
allows us to have only one place where notifications for changed
volume are sent.
sink, source: Return early from set_mute()

This avoids redundant set_mute() callback calls.

Some logging was added too.
sink-input, source-output: Add logging to set_mute()
sink, source: Allow calling set_mute() during initialization

Currently the alsa sink and source write directly to s->muted during
initialization, but I think it's better to avoid direct writes, and
use the set_mute() function instead, because that makes it easier to
figure out where s->muted is modified. This patch prevents the
set_mute() call from crashing in the state assertion.
echo-cancel: Remove redundant get_mute() callback

The callback just called pa_source_output_get_mute(), which doesn't
have any side effects, and the return value wasn't used either, so
the callback was essentially a no-op.
sink, source: Call set_mute() from mute_changed()

This refactoring reduces duplication, as mute_changed() used to do the
same things as set_mute(). Other benefits are improved logging
(set_mute() logs the mute change, mute_changed() used to not do that)
and the soft mute state is kept up to date, because set_mute() sends
the SET_MUTE message to the IO thread.

The set_mute_in_progress flag is an extra precaution for preventing
recursion in case a sink/source implementation's set_mute() callback
causes mute_changed() to be called. Currently there are no such
implementations, but I think that would be a valid thing to do, so
some day there might be such implementation.
sink, source: Assign to s->muted from only one place

Forcing all mute changes to go through set_mute() makes it easier to
check where the muted field is changed, and it also allows us to have
only one place where notifications for changed mute are sent.