On Tue, 22 Oct 2024 at 12:28, Manivannan Sadhasivam via B4 Relay
<devnull+manivannan.sadhasivam.linaro.org@xxxxxxxxxx> wrote:
>
> From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
>
> This makes the pci_bus_add_device() API easier to maintain. Also add more
> comments to the helper to describe how the devices are created.
>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>
> ---
> drivers/pci/bus.c | 59 ++++++++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 41 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
> index 351af581904f..c4cae1775c9e 100644
> --- a/drivers/pci/bus.c
> +++ b/drivers/pci/bus.c
> @@ -321,6 +321,46 @@ void __weak pcibios_resource_survey_bus(struct pci_bus *bus) { }
>
> void __weak pcibios_bus_add_device(struct pci_dev *pdev) { }
>
> +/*
> + * Create pwrctl devices (if required) for the PCI devices to handle the power
> + * state.
> + */
> +static void pci_pwrctl_create_devices(struct pci_dev *dev)
> +{
> + struct device_node *np = dev_of_node(&dev->dev);
> + struct device *parent = &dev->dev;
> + struct platform_device *pdev;
> +
> + /*
> + * First ensure that we are starting from a PCI bridge and it has a
> + * corresponding devicetree node.
> + */
> + if (np && pci_is_bridge(dev)) {
> + /*
> + * Now look for the child PCI device nodes and create pwrctl
> + * devices for them. The pwrctl device drivers will manage the
> + * power state of the devices.
> + */
> + for_each_child_of_node_scoped(np, child) {
> + /*
> + * First check whether the pwrctl device really needs to
> + * be created or not. This is decided based on at least
> + * one of the power supplies being defined in the
> + * devicetree node of the device.
> + */
> + if (!of_pci_is_supply_present(child)) {
> + pci_dbg(dev, "skipping OF node: %s\n", child->name);
> + return;
> + }
> +
> + /* Now create the pwrctl device */
> + pdev = of_platform_device_create(child, NULL, parent);
> + if (!pdev)
> + pci_err(dev, "failed to create OF node: %s\n", child->name);
> + }
> + }
> +}
> +
> /**
> * pci_bus_add_device - start driver for a single device
> * @dev: device to add
> @@ -345,24 +385,7 @@ void pci_bus_add_device(struct pci_dev *dev)
> pci_proc_attach_device(dev);
> pci_bridge_d3_update(dev);
>
> - if (dev_of_node(&dev->dev) && pci_is_bridge(dev)) {
> - for_each_child_of_node_scoped(dn, child) {
> - /*
> - * First check whether the pwrctl device needs to be
> - * created or not. This is decided based on at least
> - * one of the power supplies being defined in the
> - * devicetree node of the device.
> - */
> - if (!of_pci_is_supply_present(child)) {
> - pci_dbg(dev, "skipping OF node: %s\n", child->name);
> - continue;
> - }
> -
> - pdev = of_platform_device_create(child, NULL, &dev->dev);
> - if (!pdev)
> - pci_err(dev, "failed to create OF node: %s\n", child->name);
> - }
> - }
> + pci_pwrctl_create_devices(dev);
>
> /*
> * Create a device link between the PCI device and pwrctl device (if
>
> --
> 2.25.1
>
>
Would it be possible to move this into drivers/pwrctl/ and provide a
header stub for when PCI_PWRCTL is disabled in Kconfig?
Bart
