On 17/03/2024 16:52, Jan Dakinevich wrote:

On 3/15/24 13:22, Jerome Brunet wrote:

quoted

On Fri 15 Mar 2024 at 11:00, Krzysztof Kozlowski [off-list ref] wrote:

quoted

On 15/03/2024 00:21, Jan Dakinevich wrote:

quoted

This option allow to redefine the rate of DSP system clock.

And why is it suitable for bindings? Describe the hardware, not what you
want to do in the driver.

quoted

Signed-off-by: Jan Dakinevich <redacted>
---
 Documentation/devicetree/bindings/sound/amlogic,axg-pdm.yaml | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/Documentation/devicetree/bindings/sound/amlogic,axg-pdm.yaml b/Documentation/devicetree/bindings/sound/amlogic,axg-pdm.yaml
index df21dd72fc65..d2f23a59a6b6 100644
--- a/Documentation/devicetree/bindings/sound/amlogic,axg-pdm.yaml
+++ b/Documentation/devicetree/bindings/sound/amlogic,axg-pdm.yaml

@@ -40,6 +40,10 @@ properties:
   resets:
     maxItems: 1
 
+  sysrate:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description: redefine rate of DSP system clock

No vendor prefix, so is it a generic property? Also, missing unit
suffix, but more importantly I don't understand why this is a property
of hardware.

+1.

The appropriate way to set rate of the clock before the driver take over
is 'assigned-rate', if you need to customize this for different
platform.

It would be great, but it doesn't work. Below, is what I want to see:

	assigned-clocks =
		<&clkc_audio AUD2_CLKID_PDM_SYSCLK_SEL>,
		<&clkc_audio AUD2_CLKID_PDM_SYSCLK_DIV>;
	assigned-clock-parents =
		<&clkc_pll CLKID_FCLK_DIV3>,
		<0>;
	assigned-clock-rates =
		<0>,
		<256000000>;

But regardles of this declaration, PDM's driver unconditionally sets

That's driver's problem. You do not change bindings, just because your
driver behaves differently. Just fix driver.

sysclk'rate to 250MHz and throws away everything that was configured
before, reparents audio2_pdm_sysclk_mux to hifi_pll and changes
hifi_pll's rate.

This value 250MHz is declared here:

static const struct axg_pdm_cfg axg_pdm_config = {
	.filters = &axg_default_filters,
	.sys_rate = 250000000,
};

The property 'sysrate' is intended to redefine hardcoded 'sys_rate'
value in 'axg_pdm_config'.

What does it have to do with bindings? Change driver if you are not
happy how it operates.

Best regards,
Krzysztof