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PCI/pwrctrl: Skip scanning for the device further if pwrctrl device is created

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The pwrctrl core will rescan the bus once the device is powered on. So
there is no need to continue scanning for the device further.

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20250116-pci-pwrctrl-slot-v3-3-827473c8fbf4@linaro.org
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
This commit is contained in:
Manivannan Sadhasivam 2025-01-16 19:39:13 +05:30 committed by Krzysztof Wilczyński
parent 2d923930f2
commit 2489eeb777
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GPG Key ID: 7C64768D3DE334E7
1 changed files with 17 additions and 10 deletions
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27
drivers/pci/probe.c
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@ -2495,11 +2495,7 @@ bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,
}
EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);
/*
* Create pwrctrl device (if required) for the PCI device to handle the power
* state.
*/
static void pci_pwrctrl_create_device(struct pci_bus *bus, int devfn)
static struct platform_device *pci_pwrctrl_create_device(struct pci_bus *bus, int devfn)
{
struct pci_host_bridge *host = pci_find_host_bridge(bus);
struct platform_device *pdev;
@ -2507,7 +2503,7 @@ static void pci_pwrctrl_create_device(struct pci_bus *bus, int devfn)
np = of_pci_find_child_device(dev_of_node(&bus->dev), devfn);
if (!np || of_find_device_by_node(np))
return;
return NULL;
/*
* First check whether the pwrctrl device really needs to be created or
@ -2516,13 +2512,17 @@ static void pci_pwrctrl_create_device(struct pci_bus *bus, int devfn)
*/
if (!of_pci_supply_present(np)) {
pr_debug("PCI/pwrctrl: Skipping OF node: %s\n", np->name);
return;
return NULL;
}
/* Now create the pwrctrl device */
pdev = of_platform_device_create(np, NULL, &host->dev);
if (!pdev)
pr_err("PCI/pwrctrl: Failed to create pwrctrl device for OF node: %s\n", np->name);
if (!pdev) {
pr_err("PCI/pwrctrl: Failed to create pwrctrl device for node: %s\n", np->name);
return NULL;
}
return pdev;
}
/*
@ -2534,7 +2534,14 @@ static struct pci_dev *pci_scan_device(struct pci_bus *bus, int devfn)
struct pci_dev *dev;
u32 l;
pci_pwrctrl_create_device(bus, devfn);
/*
* Create pwrctrl device (if required) for the PCI device to handle the
* power state. If the pwrctrl device is created, then skip scanning
* further as the pwrctrl core will rescan the bus after powering on
* the device.
*/
if (pci_pwrctrl_create_device(bus, devfn))
return NULL;
if (!pci_bus_read_dev_vendor_id(bus, devfn, &l, 60*1000))
return NULL;