From: Misael Lopez Cruz Date: Wed, 12 Nov 2014 14:38:05 +0000 (+0200) Subject: ASoC: davinci-mcasp: Add overrun/underrun event handling X-Git-Tag: omap-for-v3.19/fixes-rc1~126^2~20^2~18^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a7a3324a602cd7ebabfb7f5990006ec4f3d6449f;p=pandora-kernel.git ASoC: davinci-mcasp: Add overrun/underrun event handling An underrun (playback) event occurs when the serializer transfer data from the XRBUF buffer to the XRSR shift register, but the XRBUF hasn't been filled. Similarly, the overrun (capture) event occurs when data from the XRSR shift register is transferred to the XRBUF but it hasn't been read yet. These events are handled as XRUN events that cause the pcm to stop. The stream has to be explicitly restarted by the userspace which ensures that after stopping/starting McASP the data transfer is aligned with DMA. The other possibility was to internally stop and start McASP without DMA even knowing about it. Signed-off-by: Misael Lopez Cruz Signed-off-by: Peter Ujfalusi Signed-off-by: Mark Brown --- Reading git-diff-tree failed