[RFC 6/9] PCI: create platform devices for child OF nodes of the port node

From: Bartosz Golaszewski
Date: Thu Feb 01 2024 - 10:57:54 EST


From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

In order to introduce PCI power-sequencing, we need to create platform
devices for child nodes of the port node. They will get matched against
the pwrseq drivers (if one exists) and then the actual PCI device will
reuse the node once it's detected on the bus.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
---
drivers/pci/bus.c | 9 ++++++++-
drivers/pci/remove.c | 2 ++
2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index 826b5016a101..17ab41094c4e 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>

@@ -342,8 +343,14 @@ void pci_bus_add_device(struct pci_dev *dev)
*/
pcibios_bus_add_device(dev);
pci_fixup_device(pci_fixup_final, dev);
- if (pci_is_bridge(dev))
+ if (pci_is_bridge(dev)) {
of_pci_make_dev_node(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);
+ }
pci_create_sysfs_dev_files(dev);
pci_proc_attach_device(dev);
pci_bridge_d3_update(dev);
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index d749ea8250d6..fc9db2805888 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)
@@ -22,6 +23,7 @@ static void pci_stop_dev(struct pci_dev *dev)
device_release_driver(&dev->dev);
pci_proc_detach_device(dev);
pci_remove_sysfs_dev_files(dev);
+ of_platform_depopulate(&dev->dev);
of_pci_remove_node(dev);

pci_dev_assign_added(dev, false);
--
2.40.1