Re: [PATCH v2] usb: xhci-mvebu: use regulator_set_enable_if_allowed()

On 8/22/26 11:20 AM, Bruno Banelli wrote:
> Since commit 4fcba5d556b4 ("regulator: implement basic reference
> counter") regulator_set_enable() returns -EALREADY when a fixed or
> GPIO regulator has already been enabled. On boards whose VBUS
> regulator carries regulator-always-on or regulator-boot-on -
> armada-8040-mcbin.dts is one - regulator_autoset() enables it during
> the regulator's own probe, so the subsequent enable in xhci_usb_probe()
> fails and the controller is never registered:
> 
>    starting USB...
>    Failed to turn ON the VBUS regulator
>    Bus usb3@500000: probe failed, error -114
>    No USB controllers found
> 
> Use regulator_set_enable_if_allowed(), which tolerates -EALREADY, in
> the same way as commit 0830333c4743 ("usb: ehci-generic: Use
> regulator_set_enable_if_allowed") and the other drivers converted
> after the reference counter was introduced. Also tolerate -ENOSYS,
> which include/power/regulator.h returns unconditionally from its
> !DM_REGULATOR stub, matching the check ehci-generic.c already makes.
> 
> Tested on a SolidRun MACCHIATObin (Armada 8040), where USB mass
> storage now enumerates.
> 
> Fixes: 4fcba5d556b4 ("regulator: implement basic reference counter")
> Signed-off-by: Bruno Banelli <[email protected]>
> ---
>   drivers/usb/host/xhci-mvebu.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/host/xhci-mvebu.c b/drivers/usb/host/xhci-mvebu.c
> index c294a56b3c..f932acf848 100644
> --- a/drivers/usb/host/xhci-mvebu.c
> +++ b/drivers/usb/host/xhci-mvebu.c
> @@ -51,8 +51,8 @@ static int xhci_usb_probe(struct udevice *dev)
>   
>   	ret = device_get_supply_regulator(dev, "vbus-supply", &regulator);
>   	if (!ret) {
> -		ret = regulator_set_enable(regulator, true);
> -		if (ret) {
> +		ret = regulator_set_enable_if_allowed(regulator, true);
> +		if (ret && ret != -ENOSYS) {
>   			printf("Failed to turn ON the VBUS regulator\n");
You could also turn this printf() into dev_err() in a separate patch.

This one is:

Reviewed-by: Marek Vasut <[email protected]>

Thanks !