mirror of https://gitee.com/openkylin/linux.git
8b5e2e396b
The bf5xx-i2s{,-pcm} and bf5xx-tdm{-pcm} drivers are nearly identical. Both are
for the same hardware each supporting a slight different subset of the hardware.
The bf5xx-i2s driver supports 2 channel I2S mode while the bf5xx-tdm driver
supports TDM mode and channel remapping. This patch adds support for TDM mode
and channel remapping to the bf5xx-i2s driver so that we'll eventually be able
to retire the bf5xx-tdm driver. Unfortunately the hardware is fixed to using 8
channels in TDM mode. The bf5xx-tdm driver jumps through a few hoops to make it
work well with other channel counts as well:
* Don't support mmap
* Translate between internal frame size (which is always 8 * sample_size)
and ALSA frame size (which depends on the channel count)
* Have special copy and silence callbacks which are aware of the mismatch
between internal and ALSA frame size
* Reduce the maximum buffer size to ensure that there is enough headroom for
dummy data.
The bf5xx-i2s driver is going to use the same mechanisms when being used int
TDM mode.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
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| .. | ||
| aoa | ||
| arm | ||
| atmel | ||
| core | ||
| drivers | ||
| firewire | ||
| i2c | ||
| isa | ||
| mips | ||
| oss | ||
| parisc | ||
| pci | ||
| pcmcia | ||
| ppc | ||
| sh | ||
| soc | ||
| sparc | ||
| spi | ||
| synth | ||
| usb | ||
| Kconfig | ||
| Makefile | ||
| ac97_bus.c | ||
| last.c | ||
| sound_core.c | ||
| sound_firmware.c | ||