From 30ccf078f8e4944db94007a6d0c56dda1057ffed Mon Sep 17 00:00:00 2001 From: Manivannan Sadhasivam Date: Fri, 25 Oct 2024 13:24:52 +0530 Subject: [PATCH] PCI/pwrctl: Create pwrctl device only if at least one power supply is present MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently, pwrctl devices are created if the corresponding PCI nodes are defined in devicetree. But this is not correct, because not all PCI nodes require pwrctl support. Pwrctl comes into the picture only when the device requires kernel to manage its power state. This can be determined using the power supply properties present in the devicetree node of the device. Add of_pci_supply_present() to check whether the devicetree contains at least one power supply property for a device. If one is present, create a pwrctl device for that PCI node. Suggested-by: Dmitry Baryshkov Fixes: 8fb18619d910 ("PCI/pwrctl: Create platform devices for child OF nodes of the port node") Link: https://lore.kernel.org/r/20241025-pci-pwrctl-rework-v2-2-568756156cbe@linaro.org Tested-by: Bartosz Golaszewski Tested-by: Krishna chaitanya chundru Signed-off-by: Manivannan Sadhasivam [kwilczynski: drop the NULL check in of_pci_is_supply_present()] Signed-off-by: Krzysztof Wilczyński [bhelgaas: rename of_pci_is_supply_present() to of_pci_supply_present() for readability] Signed-off-by: Bjorn Helgaas Reviewed-by: Bartosz Golaszewski Cc: stable+noautosel@kernel.org # Depends on of_platform_device_create() rework --- drivers/pci/bus.c | 11 +++++++++++ drivers/pci/of.c | 24 ++++++++++++++++++++++++ drivers/pci/pci.h | 5 +++++ 3 files changed, 40 insertions(+) diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index 9d278d3a19ff55..93bc4217012258 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -354,6 +354,17 @@ void pci_bus_add_device(struct pci_dev *dev) if (dev_of_node(&dev->dev) && pci_is_bridge(dev)) { for_each_available_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_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); diff --git a/drivers/pci/of.c b/drivers/pci/of.c index dacea3fc5128fc..ae1dcae7fe0164 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -728,6 +728,30 @@ void of_pci_make_dev_node(struct pci_dev *pdev) } #endif +/** + * of_pci_supply_present() - Check if the power supply is present for the PCI + * device + * @np: Device tree node + * + * Check if the power supply for the PCI device is present in the device tree + * node or not. + * + * Return: true if at least one power supply exists; false otherwise. + */ +bool of_pci_supply_present(struct device_node *np) +{ + struct property *prop; + char *supply; + + for_each_property_of_node(np, prop) { + supply = strrchr(prop->name, '-'); + if (supply && !strcmp(supply, "-supply")) + return true; + } + + return false; +} + #endif /* CONFIG_PCI */ /** diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 14d00ce45bfa95..64c6ca6de8029e 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -746,6 +746,7 @@ void pci_set_bus_of_node(struct pci_bus *bus); void pci_release_bus_of_node(struct pci_bus *bus); int devm_of_pci_bridge_init(struct device *dev, struct pci_host_bridge *bridge); +bool of_pci_supply_present(struct device_node *np); #else static inline int @@ -793,6 +794,10 @@ static inline int devm_of_pci_bridge_init(struct device *dev, struct pci_host_br return 0; } +static inline bool of_pci_supply_present(struct device_node *np) +{ + return false; +} #endif /* CONFIG_OF */ struct of_changeset;