Re: [PATCH 1/3] power: regulator: Add a driver for the AXP USB power supply

[Andre Przywara <andre.przywara@arm.com>]

On Sun, 22 Jan 2023 17:46:20 -0600
Samuel Holland <samuel@sholland.org> wrote:

> This driver reports the presence/absence of voltage on the PMIC's USB
> VBUS pin. This information is used by the USB PHY driver. The
> corresponding Linux driver uses the power supply class, which does not
> exist in U-Boot. UCLASS_REGULATOR seems to be the closest match.

That's a quite clever and lean solution, since the USB PHY already
checks for such a regulator enable status. The bits match up, so:

Acked-by: Andre Przywara <andre.przywara@arm.com>

queued for sunxi/master

Cheers,
Andre

> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
> 
>  drivers/power/regulator/Kconfig         |  7 ++++
>  drivers/power/regulator/Makefile        |  1 +
>  drivers/power/regulator/axp_usb_power.c | 49 +++++++++++++++++++++++++
>  3 files changed, 57 insertions(+)
>  create mode 100644 drivers/power/regulator/axp_usb_power.c
> 
> diff --git a/drivers/power/regulator/Kconfig b/drivers/power/regulator/Kconfig
> index c346d03507..eb5aa38c1c 100644
> --- a/drivers/power/regulator/Kconfig
> +++ b/drivers/power/regulator/Kconfig
> @@ -57,6 +57,13 @@ config SPL_REGULATOR_AXP
>  	  Enable support in SPL for the regulators (DCDCs, LDOs) in the
>  	  X-Powers AXP152, AXP2xx, and AXP8xx PMICs.
>  
> +config REGULATOR_AXP_USB_POWER
> +	bool "Enable driver for X-Powers AXP PMIC USB power supply"
> +	depends on DM_REGULATOR && PMIC_AXP
> +	help
> +	  Enable support for reading the USB power supply status from
> +	  X-Powers AXP2xx and AXP8xx PMICs.
> +
>  config DM_REGULATOR_BD71837
>  	bool "Enable Driver Model for ROHM BD71837/BD71847 regulators"
>  	depends on DM_REGULATOR && DM_PMIC_BD71837
> diff --git a/drivers/power/regulator/Makefile b/drivers/power/regulator/Makefile
> index 2d97e1033a..d9e0cd5949 100644
> --- a/drivers/power/regulator/Makefile
> +++ b/drivers/power/regulator/Makefile
> @@ -8,6 +8,7 @@ obj-$(CONFIG_$(SPL_)DM_REGULATOR) += regulator-uclass.o
>  obj-$(CONFIG_REGULATOR_ACT8846) += act8846.o
>  obj-$(CONFIG_REGULATOR_AS3722)	+= as3722_regulator.o
>  obj-$(CONFIG_$(SPL_)REGULATOR_AXP) += axp_regulator.o
> +obj-$(CONFIG_$(SPL_)REGULATOR_AXP_USB_POWER) += axp_usb_power.o
>  obj-$(CONFIG_$(SPL_)DM_REGULATOR_DA9063) += da9063.o
>  obj-$(CONFIG_DM_REGULATOR_MAX77686) += max77686.o
>  obj-$(CONFIG_DM_REGULATOR_NPCM8XX) += npcm8xx_regulator.o
> diff --git a/drivers/power/regulator/axp_usb_power.c b/drivers/power/regulator/axp_usb_power.c
> new file mode 100644
> index 0000000000..f32fb6a92d
> --- /dev/null
> +++ b/drivers/power/regulator/axp_usb_power.c
> @@ -0,0 +1,49 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +
> +#include <dm/device.h>
> +#include <errno.h>
> +#include <power/pmic.h>
> +#include <power/regulator.h>
> +
> +#define AXP_POWER_STATUS		0x00
> +#define AXP_POWER_STATUS_VBUS_PRESENT		BIT(5)
> +
> +static int axp_usb_power_get_enable(struct udevice *dev)
> +{
> +	int ret;
> +
> +	ret = pmic_reg_read(dev->parent, AXP_POWER_STATUS);
> +	if (ret < 0)
> +		return ret;
> +
> +	return !!(ret & AXP_POWER_STATUS_VBUS_PRESENT);
> +}
> +
> +static const struct dm_regulator_ops axp_usb_power_ops = {
> +	.get_enable		= axp_usb_power_get_enable,
> +};
> +
> +static int axp_usb_power_probe(struct udevice *dev)
> +{
> +	struct dm_regulator_uclass_plat *uc_plat = dev_get_uclass_plat(dev);
> +
> +	uc_plat->type = REGULATOR_TYPE_FIXED;
> +
> +	return 0;
> +}
> +
> +static const struct udevice_id axp_usb_power_ids[] = {
> +	{ .compatible = "x-powers,axp202-usb-power-supply" },
> +	{ .compatible = "x-powers,axp221-usb-power-supply" },
> +	{ .compatible = "x-powers,axp223-usb-power-supply" },
> +	{ .compatible = "x-powers,axp813-usb-power-supply" },
> +	{ }
> +};
> +
> +U_BOOT_DRIVER(axp_usb_power) = {
> +	.name		= "axp_usb_power",
> +	.id		= UCLASS_REGULATOR,
> +	.of_match	= axp_usb_power_ids,
> +	.probe		= axp_usb_power_probe,
> +	.ops		= &axp_usb_power_ops,
> +};