Commit Graph

2 Commits

Author SHA1 Message Date
Russell King
f5ce405722 drm: bridge/dw_hdmi-ahb-audio: parse ELD from HDMI driver
Parse the ELD (EDID like data) stored from the HDMI driver to restrict
the sample rates and channels which are available to ALSA.  This causes
the ALSA device to reflect the capabilities of the overall audio path,
not just what is supported at the HDMI source interface level.

Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-10-09 17:17:24 +01:00
Russell King
7ed6c665e1 drm: bridge/dw_hdmi-ahb-audio: add audio driver
Add ALSA based HDMI AHB audio driver for dw_hdmi.  The only buffer
format supported by the hardware is its own special IEC958 based format,
which is not compatible with any ALSA format.  To avoid doing too much
data manipulation within the driver, we support only ALSAs IEC958 LE and
24-bit PCM formats for 2 to 6 channels, which we convert to its hardware
format.

A more desirable solution would be to have this conversion in userspace,
but ALSA does not appear to allow such transformations outside of
libasound itself.

Reviewed-by: Takashi Iwai <tiwai@suse.de>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2015-10-09 17:14:12 +01:00