Re: [PATCH net-next 3/4] net: pse-pd: realtek-pse-mcu: configure global power budget

[Kory Maincent <kory.maincent@bootlin.com>]

On 11/3/26 23:03, Jonas Jelonek wrote:
> Use the optional VMAIN regulator power budget to configure the MCU's
> aggregate PoE power limit during probe. Quantize the available budget to
> the protocol's 100 mW units and reserve exactly that amount through the
> regulator core.
> 
> The regulator budget represents the usable PoE allowance. Program zero
> reserved power so the previous firmware guard band does not further reduce
> that allowance.
> 
> Require a finite budget of at least one protocol unit when vmain-supply is
> provided. Program the budget before selecting dynamic power management and
> ungating the ports, so enforcement starts with the regulator-derived limit.
> 
> Enable VMAIN before hardware initialization and register one managed cleanup
> action to free any reserved budget and release the enable reference on probe
> failure and driver removal. Record each successful reservation immediately
> so subsequent initialization failures are covered by this action.
> 
> Read the current budget index before programming the MCU. Retain the
> programmed MCU limit on probe failure and driver removal, as reducing that
> limit to zero would interrupt ongoing power delivery.
> 
> Boards without vmain-supply retain their existing firmware-managed
> budget.
> 
> Signed-off-by: Jonas Jelonek <jonas@jonasjelonek.de>
> ---

...

>   
> +static void rtpse_mcu_cleanup_vmain(void *data)
> +{
> +	struct rtpse_mcu_ctrl *pse = data;
> +
> +	if (pse->requested_budget_mW)
> +		regulator_free_power_budget(pse->vmain, pse->requested_budget_mW);
> +	regulator_disable(pse->vmain);
> +}

Following patch 4 logic, you might not want to disable the PSE 
controller power supply, this will lead to a power off of all your PIs.
I think you should still free the power budget, to not allocate it twice 
if the module is loaded again.

Else is ok to me.

-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com