[alsa-devel] [PATCH 2/2] ARM: Dove: Add the audio device to the Cubox DT

Jean-Francois Moine moinejf at free.fr
Sun Sep 1 09:04:20 CEST 2013

On Sat, 31 Aug 2013 12:24:31 +0100
Russell King - ARM Linux <linux at arm.linux.org.uk> wrote:

> > According to the Dove specification, the audio controller works with
> > the samples rates 44.1, 48 and 96 kHz, so, I don't see the usage of the
> > external clock, except when using the two audio controllers with
> > different sample rates.  
> I don't see what the Dove specification has to do with that statement:
> what the Dove spec says is that if you use just the internal DCO, then
> only 44.1kHz, 48kHz and 96kHz are supported (with some trimming of that.)
> However, the use of an external clock allows further rates to be supported.
> If you have an external clock, there is no requirement to use the DCO for
> those sample rates - you can if you wish, or you can use the external clock.
> The mainline driver implements the use of the DCO for the standard 44.1,
> 48 and 96kHz rates, otherwise it uses the external clock if present.  This
> is entirely conformant with the Dove spec.


I looked again at the Armada-510-Functional-Spec, and I found:

- section 12.1
	I2S Supported Features
		An audio sample rate (Fs) of 44.1/48/96 kHz.
	S/PDIF Supported Features
		The IEC60958-1, IEC60958-3, and IEC61937 specifications.
		An audio sample rate (Fs) of 44.1/48/96 kHz.

- Table 436: Clocks Control Register
	     Offset: Unit0: 0x000B1230, Unit1: 0x000B5230
	1:0 MCLK source RW  MCLK = 256 Fs, where Fs = 44.1 kHz, 48 kHz, 96 kHz.
			0x0 Playback should not be active when selecting an external MCLK, or moving
			    from one external MCLK to another MCLK source.
			    0 = DCO: MCLK is from DCO.
			    1 = Reserved
			    2 = Reserved
			    3 = External: MCLK is from an external source.

As they don't work with my TV set, may you confirm that these webradios


work for you with the external clock? (sample rates resp. 33.075, 24
and 22.05 kHz)

Ken ar c'hentañ	|	      ** Breizh ha Linux atav! **
Jef		|		http://moinejf.free.fr/

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