On 03/02/2015 09:35 PM, Pierre-Louis Bossart wrote:
Hi Jyri,
On 3/2/15 8:14 AM, Jyri Sarha wrote:
Optional dai-link subnode properties:
+- samplewidth-constraints : List of integers describing supported
+ sample widths in number of bits.
There are quite a few platforms where the number of bits for valid audio
bits differs from the number of bits per slot, e.g. 24 bits with 25 bit
slots, or 24 bits in 32 bit slots. How would this be represented? This
concept is present for the TDM case but not the simple one.
-Pierre
As these are dai-link level properties the idea is to set constraints to
sample-width on the digital audio link, usually i2s. That is why the
constraint is set based on sample-width and not physical width.
The number if significant bits in the sample-word should in a normal
case be a property of the codec, if such a property is needed. On the
other hand the limits for the physical layout in the system memory are
usually set by the platform driver (= DMA HW), so such a property should
- in a normal case - go to cpu-dai node. Since these cases can usually
be associated to either end of the link, there should be no need for
such properties in the machine driver.
I am not sure what you have in mind with the TDM case. In some cases a
similar constraint property for number of channels could help.
Best regards,
Jyri
+- rate-constraints : List of integers describing supported
+ sample samplerates in Hz.
- format : CPU/CODEC common audio format.
"i2s", "right_j", "left_j" , "dsp_a"
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
