[PATCH V2 1/2] PCI: host-generic: Simplify return value handling in pci_host_common_parse_port(s)

[Hongxing Zhu]

> -----Original Message-----
> From: Sherry Sun (OSS) <sherry.sun at oss.nxp.com>
> Sent: Monday, May 25, 2026 2:55 PM
> To: Hongxing Zhu <hongxing.zhu at nxp.com>; l.stach at pengutronix.de; Frank Li
> <frank.li at nxp.com>; bhelgaas at google.com; lpieralisi at kernel.org;
> kwilczynski at kernel.org; mani at kernel.org; robh at kernel.org;
> s.hauer at pengutronix.de; kernel at pengutronix.de; festevam at gmail.com;
> will at kernel.org
> Cc: imx at lists.linux.dev; linux-pci at vger.kernel.org; linux-arm-
> kernel at lists.infradead.org; linux-kernel at vger.kernel.org; Sherry Sun
> <sherry.sun at nxp.com>
> Subject: [PATCH V2 1/2] PCI: host-generic: Simplify return value handling in
> pci_host_common_parse_port(s)
> 
> 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 parse 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 return 0 on success and a negative error code on real failures.
> 
> Signed-off-by: Sherry Sun <sherry.sun at nxp.com>
Reviewed-by: Richard Zhu <hongxing.zhu at nxp.com>

Best Regards
Richard Zhu
> ---
>  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 2ce6f4b66133..c93de5a10758 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