[PATCH 1/2] PCI: host-generic: Simplify return value handling in pci_host_common_parse_port(s)

[Sherry Sun (OSS)]

From: Sherry Sun <sherry.sun at nxp.com>

The pci_host_common_parse_port() shouldn't check the RC-level binding.
That's a policy decision that belongs to the caller, not this common
helper.

Simplify pci_host_common_parse_port() to only parses properties from the
Root Port(and its children) without checking the RC node. Also change
pci_host_common_parse_ports() to return 0 when no ports are found, since
it is not an error.

So now both functions won't return failure for "property not found" or
"port not found", they purely returns 0 on success and a negative error
code on real failures.

Signed-off-by: Sherry Sun <sherry.sun at nxp.com>
---
 drivers/pci/controller/pci-host-common.c | 29 ++++--------------------
 1 file changed, 5 insertions(+), 24 deletions(-)

diff --git a/drivers/pci/controller/pci-host-common.c b/drivers/pci/controller/pci-host-common.c
index 67455caaf9e6..7ce5a939e3d9 100644
--- a/drivers/pci/controller/pci-host-common.c
+++ b/drivers/pci/controller/pci-host-common.c
@@ -108,8 +108,7 @@ static int pci_host_common_parse_perst(struct device *dev,
  * dependencies and the driver may fail to operate if required resources
  * are missing.
  *
- * Return: 0 on success, -ENODEV if PERST# found in RC node (legacy binding
- * should be used), Other negative error codes on failure.
+ * Return: 0 on success, negative error codes on failure.
  */
 static int pci_host_common_parse_port(struct device *dev,
 				      struct pci_host_bridge *bridge,
@@ -128,22 +127,6 @@ static int pci_host_common_parse_port(struct device *dev,
 	if (ret)
 		return ret;
 
-	/*
-	 * 1. PERST# found in RP or its child nodes - list is not empty,
-	 *    continue
-	 *
-	 * 2. PERST# not found in RP/children, but found in RC node -
-	 *    return -ENODEV to fallback legacy binding
-	 *
-	 * 3. PERST# not found anywhere - list is empty, continue (optional
-	 *    PERST#)
-	 */
-	if (list_empty(&port->perst)) {
-		if (of_property_present(dev->of_node, "reset-gpios") ||
-		    of_property_present(dev->of_node, "reset-gpio"))
-			return -ENODEV;
-	}
-
 	INIT_LIST_HEAD(&port->list);
 	list_add_tail(&port->list, &bridge->ports);
 
@@ -158,13 +141,11 @@ static int pci_host_common_parse_port(struct device *dev,
  * Iterate through child nodes of the host bridge and parse Root Port
  * properties (currently only reset GPIOs).
  *
- * Return: 0 on success, -ENODEV if no ports found or PERST# found in RC
- * node (legacy binding should be used), Other negative error codes on
- * failure.
+ * Return: 0 on success, negative error codes on failure.
  */
 int pci_host_common_parse_ports(struct device *dev, struct pci_host_bridge *bridge)
 {
-	int ret = -ENODEV;
+	int ret = 0;
 
 	for_each_available_child_of_node_scoped(dev->of_node, of_port) {
 		if (!of_node_is_type(of_port, "pci"))
@@ -174,8 +155,8 @@ int pci_host_common_parse_ports(struct device *dev, struct pci_host_bridge *brid
 			goto err_cleanup;
 	}
 
-	if (ret)
-		return ret;
+	if (list_empty(&bridge->ports))
+		return 0;
 
 	return devm_add_action_or_reset(dev, pci_host_common_delete_ports,
 					&bridge->ports);
-- 
2.37.1