[PATCH v9 3/5] PCI/pwrctl: Create platform devices for child OF nodes of the port node

[Bartosz Golaszewski <brgl@bgdev.pl>]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

In preparation for introducing PCI device power control - a set of
library functions that will allow powering-up of PCI devices before
they're detected on the PCI bus - we need to populate the devices
defined on the device-tree.

We are reusing the platform bus as it provides us with all the
infrastructure we need to match the pwrctl drivers against the
compatibles from OF nodes.

These platform devices will be probed by the driver core and bound to
the PCI pwrctl drivers we'll introduce later.

Tested-by: Amit Pundir <amit.pundir@linaro.org>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD, SM8650-QRD & SM8650-HDK
Tested-by: Caleb Connolly <caleb.connolly@linaro.org> # OnePlus 8T
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/pci/bus.c    | 9 +++++++++
 drivers/pci/remove.c | 3 ++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index dfc99b3cb958..e4735428814d 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -12,6 +12,7 @@
 #include <linux/errno.h>
 #include <linux/ioport.h>
 #include <linux/of.h>
+#include <linux/of_platform.h>
 #include <linux/proc_fs.h>
 #include <linux/slab.h>
 
@@ -348,6 +349,14 @@ void pci_bus_add_device(struct pci_dev *dev)
 		pci_warn(dev, "device attach failed (%d)\n", retval);
 
 	pci_dev_assign_added(dev, true);
+
+	if (pci_is_bridge(dev)) {
+		retval = of_platform_populate(dev->dev.of_node, NULL, NULL,
+					      &dev->dev);
+		if (retval)
+			pci_err(dev, "failed to populate child OF nodes (%d)\n",
+				retval);
+	}
 }
 EXPORT_SYMBOL_GPL(pci_bus_add_device);
 
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index d749ea8250d6..910387e5bdbf 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/pci.h>
 #include <linux/module.h>
+#include <linux/of_platform.h>
 #include "pci.h"
 
 static void pci_free_resources(struct pci_dev *dev)
@@ -18,7 +19,7 @@ static void pci_stop_dev(struct pci_dev *dev)
 	pci_pme_active(dev, false);
 
 	if (pci_dev_is_added(dev)) {
-
+		of_platform_depopulate(&dev->dev);
 		device_release_driver(&dev->dev);
 		pci_proc_detach_device(dev);
 		pci_remove_sysfs_dev_files(dev);
-- 
2.40.1