6.15-stable review patch. If anyone has any objections, please let me know.
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From: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org
commit 8c493cc91f3a1102ad2f8c75ae0cf80f0a057488 upstream.
If devicetree describes power supplies related to a PCI device, we unnecessarily created a pwrctrl device even if CONFIG_PCI_PWRCTL was not enabled.
We only need pci_pwrctrl_create_device() when CONFIG_PCI_PWRCTRL is enabled. Compile it out when CONFIG_PCI_PWRCTRL is not enabled.
When pci_pwrctrl_create_device() creates and returns a pwrctrl device, pci_scan_device() doesn't enumerate the PCI device. It assumes the pwrctrl core will rescan the bus after turning on the power. However, if CONFIG_PCI_PWRCTRL is not enabled, the rescan never happens, which breaks PCI enumeration on any system that describes power supplies in devicetree but does not use pwrctrl.
Jim reported that some brcmstb platforms break this way. The brcmstb driver is still broken if CONFIG_PCI_PWRCTRL is enabled, but this commit at least allows brcmstb to work when it's NOT enabled.
Fixes: 957f40d039a9 ("PCI/pwrctrl: Move creation of pwrctrl devices to pci_scan_device()") Reported-by: Jim Quinlan james.quinlan@broadcom.com Link: https://lore.kernel.org/r/CA+-6iNwgaByXEYD3j=-+H_PKAxXRU78svPMRHDKKci8AGXAUP... Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Lukas Wunner lukas@wunner.de Cc: stable@vger.kernel.org # v6.15 Link: https://patch.msgid.link/20250701064731.52901-1-manivannan.sadhasivam@linaro... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pci/probe.c | 7 +++++++ 1 file changed, 7 insertions(+)
--- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -2508,6 +2508,7 @@ bool pci_bus_read_dev_vendor_id(struct p } EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
+#if IS_ENABLED(CONFIG_PCI_PWRCTRL) static struct platform_device *pci_pwrctrl_create_device(struct pci_bus *bus, int devfn) { struct pci_host_bridge *host = pci_find_host_bridge(bus); @@ -2537,6 +2538,12 @@ static struct platform_device *pci_pwrct
return pdev; } +#else +static struct platform_device *pci_pwrctrl_create_device(struct pci_bus *bus, int devfn) +{ + return NULL; +} +#endif
/* * Read the config data for a PCI device, sanity-check it,