Re: [PATCH v2 1/2] platform/x86/intel: Introduce Intel Elkhart Lake PSE I/O

From: Andy Shevchenko
Date: Mon Nov 10 2025 - 02:25:39 EST


On Mon, Nov 10, 2025 at 10:56:40AM +0530, Raag Jadav wrote:
> Intel Elkhart Lake Programmable Service Engine (PSE) includes two PCI
> devices that expose two different capabilities of GPIO and Timed I/O
> as a single PCI function through shared MMIO with below layout.
>
> GPIO: 0x0000 - 0x1000
> TIO: 0x1000 - 0x2000
>
> This driver enumerates the PCI parent device and creates auxiliary child
> devices for these capabilities. The actual functionalities are provided
> by their respective auxiliary drivers.

...

> +static int ehl_pse_io_dev_add(struct pci_dev *pci, const char *name, int idx)
> +{
> + struct auxiliary_device *aux_dev;
> + struct device *dev = &pci->dev;
> + struct ehl_pse_io_dev *io_dev;
> + resource_size_t start, offset;
> + int ret;
> +
> + io_dev = devm_kzalloc(dev, sizeof(*io_dev), GFP_KERNEL);
> + if (!io_dev)
> + return -ENOMEM;
> +
> + start = pci_resource_start(pci, 0);
> + offset = EHL_PSE_IO_DEV_SIZE * idx;
> +
> + io_dev->irq = pci_irq_vector(pci, idx);
> + io_dev->mem = DEFINE_RES_MEM(start + offset, EHL_PSE_IO_DEV_SIZE);
> +
> + aux_dev = &io_dev->aux_dev;
> + aux_dev->name = name;
> + aux_dev->id = (pci_domain_nr(pci->bus) << 16) | pci_dev_id(pci);
> + aux_dev->dev.parent = dev;
> + aux_dev->dev.release = ehl_pse_io_dev_release;
> +
> + ret = auxiliary_device_init(aux_dev);
> + if (ret)
> + return ret;
> +
> + ret = auxiliary_device_add(aux_dev);
> + if (ret) {
> + auxiliary_device_uninit(aux_dev);
> + return ret;
> + }

Can it be now auxiliary_device_create() ?

> + return devm_add_action_or_reset(dev, ehl_pse_io_dev_destroy, aux_dev);
> +}

...

> +#define auxiliary_dev_to_ehl_pse_io_dev(auxiliary_dev) \
> + container_of(auxiliary_dev, struct ehl_pse_io_dev, aux_dev)

Wondering if we may use container_of_const()

--
With Best Regards,
Andy Shevchenko