On 24/02/2023 11:54, Chancel Liu wrote:
On 22/02/2023 12:39, Chancel Liu wrote:
This property specifies power up to audio out time. It's necessary beacause this device has to wait some time before ready to output audio
typo... run spellcheck, also on the subject
after MCLK, BCLK and MUTE=1 are enabled. For more details about the timing constraints, please refer to WTN0302 on
Signed-off-by: Chancel Liu chancel.liu@nxp.com
.../devicetree/bindings/sound/wlf,wm8524.yaml | 10
++++++++++
1 file changed, 10 insertions(+)
diff --git a/Documentation/devicetree/bindings/sound/wlf,wm8524.yaml
b/Documentation/devicetree/bindings/sound/wlf,wm8524.yaml
index 09c54cc7de95..54b4da5470e4 100644 --- a/Documentation/devicetree/bindings/sound/wlf,wm8524.yaml +++ b/Documentation/devicetree/bindings/sound/wlf,wm8524.yaml @@ -21,6 +21,15 @@ properties: description: a GPIO spec for the MUTE pin.
- wlf,power-up-delay-ms:
- maximum: 1500
maximum is 1003. Where do you see 1500?
minimum: 82
Yes, you are absolutely right. From the power up to audio out timing table in WTN0302, the minimum number is 82 and the maximum is 1003.
Consider the following possibilities:
- These timings may depend on the system design
- These timings may be simulated results
- These timings may be the minimum values
I set a larger value trying to extend the time. The larger value of course introduces unwanted time delay but it benefits on avoiding beginning audio lost.
I also did some tests on a board. If I want to work on 48KHZ sample rate and 512FS, the recommended value is 143. But the test result showed 143ms is not enough. I increased the value to 500ms and could hear the beginning sound.
Maybe you miss proper regulator ramp-up?
Maybe it's a better choice to let DT set the suitable value? Is there a similar situation before?
That's not really good argument. DT should describe hardware and if this property does not match hardware, it means you mix this with something else. Something not for DT.
Best regards, Krzysztof
OK. The patches for adding such property are not really good. I need to find a better way to address the issue.
I think PATCH 1 and PATCH 3 can be kept. So I will modify them according comments.
Thank you for your review. That benefits me a lot.
Regards, Chancel Liu