From mboxrd@z Thu Jan 1 00:00:00 1970 From: b29396@freescale.com (Dong Aisheng) Date: Wed, 1 Aug 2012 10:46:33 +0800 Subject: [alsa-devel] [PATCH 1/1] ASoC: sgtl5000: enable VAG_POWER for LINE_IN In-Reply-To: <20120728143957.GJ2128@S2101-09.ap.freescale.net> References: <1343387922-25227-1-git-send-email-b29396@freescale.com> <20120728143957.GJ2128@S2101-09.ap.freescale.net> Message-ID: <20120801024630.GA30492@shlinux2.ap.freescale.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, Jul 28, 2012 at 10:39:59PM +0800, Shawn Guo wrote: > On Fri, Jul 27, 2012 at 07:18:42PM +0800, Dong Aisheng wrote: > > From: Dong Aisheng > > > > LINE_IN also needs VAG_POWER on or we may hear noise when directly > > route LINE_IN to Headphone Mux. > > The following is what I see from sgtl5000 data sheet about VAG_POWER. > > VAG is the internal voltage reference for the ADC and DAC. > > Are you seeing any info that requires VAG_POWER in route of LINE_IN to > Headphone Mux? Or it's only a result from your testing? > No, it's from the test result. Maybe i should have added a FIXME for this. > Does it also fix the noise issue you mentioned with normal recording > (LINE_IN to ADC) before? > ADC also needs VAG power which already fixed by: commit f0cdcf3 (ASoC: sgtl5000: Enable VAG when DAC/ADC up) This patch is only for direct LINE_IN to Headphone Mux. Regards Dong Aisheng