PCI/pwrctrl: Move creation of pwrctrl devices to pci_scan_device()

Current way of creating pwrctrl devices requires iterating through the
child devicetree nodes of the PCI bridge in pci_pwrctrl_create_devices().
Even though it works, it creates confusion as there is no symmetry between
this and pci_pwrctrl_unregister() function that removes the pwrctrl
devices.

So to make these two functions symmetric, move the creation of pwrctrl
devices to pci_scan_device(). During the scan of each device in a slot,
the devicetree node (if exists) for the PCI device will be checked. If it
has the supplies populated, then the pwrctrl device will be created.

Since the PCI device scan happens so early, there would be no "struct
pci_dev" available for the device. So the host bridge is used as the
parent of all pwrctrl devices.

One nice side effect of this move is that, it is now possible to have
pwrctrl devices for PCI bridges as well (to control the supplies of PCI
slots).

Suggested-by: Lukas Wunner <lukas@wunner.de>
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-v3-1-827473c8fbf4@linaro.org
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/pci/pwrctrl/core.c b/drivers/pci/pwrctrl/core.c
index 2fb174db91e5..9cc7e2b7f2b5 100644
--- a/drivers/pci/pwrctrl/core.c
+++ b/drivers/pci/pwrctrl/core.c
@@ -44,7 +44,7 @@ static void rescan_work_func(struct work_struct *work)
 						   struct pci_pwrctrl, work);
 
 	pci_lock_rescan_remove();
-	pci_rescan_bus(to_pci_dev(pwrctrl->dev->parent)->bus);
+	pci_rescan_bus(to_pci_host_bridge(pwrctrl->dev->parent)->bus);
 	pci_unlock_rescan_remove();
 }