Re: [PATCH v2 2/7] pci: pwrctrl: add PCI pwrctrl driver for the UPD720201/UPD720202 USB 3.0 xHCI Host Controller

[Neil Armstrong <neil.armstrong@linaro.org>]

On 1/27/26 16:53, Manivannan Sadhasivam wrote:
> On Tue, Jan 27, 2026 at 10:57:29AM +0100, Neil Armstrong wrote:
>> Add support fo the Renesas UPD720201/UPD720202 USB 3.0 xHCI Host Controller
>> power control which connects over PCIe and requires specific power supplies
>> to start up.
>>
> 
> This driver only handles the supplies. So why can't you use the existing
> pwrctrl-slot driver as a fallback?

It would fit with no change, but the name "slot" doesn't match the goal here,
it's not a slot at all, it's an actual pcie IC.

Neil

> 
> - Mani
> 
>> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
>> ---
>>   drivers/pci/pwrctrl/Kconfig                 | 10 ++++
>>   drivers/pci/pwrctrl/Makefile                |  2 +
>>   drivers/pci/pwrctrl/pci-pwrctrl-upd720201.c | 88 +++++++++++++++++++++++++++++
>>   3 files changed, 100 insertions(+)
>>
>> diff --git a/drivers/pci/pwrctrl/Kconfig b/drivers/pci/pwrctrl/Kconfig
>> index e0f999f299bb..5a94e60d0d3e 100644
>> --- a/drivers/pci/pwrctrl/Kconfig
>> +++ b/drivers/pci/pwrctrl/Kconfig
>> @@ -11,6 +11,16 @@ config PCI_PWRCTRL_PWRSEQ
>>   	select POWER_SEQUENCING
>>   	select PCI_PWRCTRL
>>   
>> +config PCI_PWRCTRL_UPD720201
>> +	tristate "PCI Power Control driver for the UPD720201 USB3 Host Controller"
>> +	select PCI_PWRCTRL
>> +	help
>> +	  Say Y here to enable the PCI Power Control driver of the UPD720201
>> +	  USB3 Host Controller.
>> +
>> +	  The voltage regulators powering the rails of the PCI slots
>> +	  are expected to be defined in the devicetree node of the PCI device.
>> +
>>   config PCI_PWRCTRL_SLOT
>>   	tristate "PCI Power Control driver for PCI slots"
>>   	select PCI_PWRCTRL
>> diff --git a/drivers/pci/pwrctrl/Makefile b/drivers/pci/pwrctrl/Makefile
>> index 13b02282106c..a99f85de8a3d 100644
>> --- a/drivers/pci/pwrctrl/Makefile
>> +++ b/drivers/pci/pwrctrl/Makefile
>> @@ -5,6 +5,8 @@ pci-pwrctrl-core-y			:= core.o
>>   
>>   obj-$(CONFIG_PCI_PWRCTRL_PWRSEQ)	+= pci-pwrctrl-pwrseq.o
>>   
>> +obj-$(CONFIG_PCI_PWRCTRL_UPD720201)	+= pci-pwrctrl-upd720201.o
>> +
>>   obj-$(CONFIG_PCI_PWRCTRL_SLOT)		+= pci-pwrctrl-slot.o
>>   pci-pwrctrl-slot-y			:= slot.o
>>   
>> diff --git a/drivers/pci/pwrctrl/pci-pwrctrl-upd720201.c b/drivers/pci/pwrctrl/pci-pwrctrl-upd720201.c
>> new file mode 100644
>> index 000000000000..db96bbb69c21
>> --- /dev/null
>> +++ b/drivers/pci/pwrctrl/pci-pwrctrl-upd720201.c
>> @@ -0,0 +1,88 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Based on upd720201.c:
>> + * Copyright (C) 2024 Linaro Ltd.
>> + * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
>> + */
>> +
>> +#include <linux/device.h>
>> +#include <linux/mod_devicetable.h>
>> +#include <linux/module.h>
>> +#include <linux/pci-pwrctrl.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/regulator/consumer.h>
>> +#include <linux/slab.h>
>> +
>> +struct pci_pwrctrl_upd720201_data {
>> +	struct pci_pwrctrl ctx;
>> +	struct regulator_bulk_data *supplies;
>> +	int num_supplies;
>> +};
>> +
>> +static void devm_pci_pwrctrl_upd720201_power_off(void *data)
>> +{
>> +	struct pci_pwrctrl_upd720201_data *upd720201 = data;
>> +
>> +	regulator_bulk_disable(upd720201->num_supplies, upd720201->supplies);
>> +	regulator_bulk_free(upd720201->num_supplies, upd720201->supplies);
>> +}
>> +
>> +static int pci_pwrctrl_upd720201_probe(struct platform_device *pdev)
>> +{
>> +	struct pci_pwrctrl_upd720201_data *upd720201;
>> +	struct device *dev = &pdev->dev;
>> +	int ret;
>> +
>> +	upd720201 = devm_kzalloc(dev, sizeof(*upd720201), GFP_KERNEL);
>> +	if (!upd720201)
>> +		return -ENOMEM;
>> +
>> +	ret = of_regulator_bulk_get_all(dev, dev_of_node(dev),
>> +					&upd720201->supplies);
>> +	if (ret < 0) {
>> +		dev_err_probe(dev, ret, "Failed to get upd720201 regulators\n");
>> +		return ret;
>> +	}
>> +
>> +	upd720201->num_supplies = ret;
>> +	ret = regulator_bulk_enable(upd720201->num_supplies, upd720201->supplies);
>> +	if (ret < 0) {
>> +		dev_err_probe(dev, ret, "Failed to enable upd720201 regulators\n");
>> +		regulator_bulk_free(upd720201->num_supplies, upd720201->supplies);
>> +		return ret;
>> +	}
>> +
>> +	ret = devm_add_action_or_reset(dev, devm_pci_pwrctrl_upd720201_power_off,
>> +				       upd720201);
>> +	if (ret)
>> +		return ret;
>> +
>> +	pci_pwrctrl_init(&upd720201->ctx, dev);
>> +
>> +	ret = devm_pci_pwrctrl_device_set_ready(dev, &upd720201->ctx);
>> +	if (ret)
>> +		return dev_err_probe(dev, ret, "Failed to register pwrctrl driver\n");
>> +
>> +	return 0;
>> +}
>> +
>> +static const struct of_device_id pci_pwrctrl_upd720201_of_match[] = {
>> +	{
>> +		.compatible = "pci1912,0014",
>> +	},
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(of, pci_pwrctrl_upd720201_of_match);
>> +
>> +static struct platform_driver pci_pwrctrl_upd720201_driver = {
>> +	.driver = {
>> +		.name = "pci-pwrctrl-upd720201",
>> +		.of_match_table = pci_pwrctrl_upd720201_of_match,
>> +	},
>> +	.probe = pci_pwrctrl_upd720201_probe,
>> +};
>> +module_platform_driver(pci_pwrctrl_upd720201_driver);
>> +
>> +MODULE_AUTHOR("Neil Armstrong <neil.armstrong@linaro.org>");
>> +MODULE_DESCRIPTION("PCI Power Control driver for UPD720201 USB3 Host Controller");
>> +MODULE_LICENSE("GPL");
>>
>> -- 
>> 2.34.1
>>
>