Re: [PATCH v11 04/11] PCI: dwc: Move devm_pci_alloc_host_bridge() to the beginning of dw_pcie_host_init()

[Bjorn Helgaas]

On Thu, Mar 13, 2025 at 11:38:40AM -0400, Frank Li wrote:
> Move devm_pci_alloc_host_bridge() to the beginning of dw_pcie_host_init().
> Since devm_pci_alloc_host_bridge() is common code that doesn't depend on
> any DWC resource, moving it earlier improves code logic and readability.
> 
> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> ---
>  drivers/pci/controller/dwc/pcie-designware-host.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
> index c57831902686e..52a441662cabe 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-host.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-host.c
> @@ -452,6 +452,12 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
>  
>  	raw_spin_lock_init(&pp->lock);
>  
> +	bridge = devm_pci_alloc_host_bridge(dev, 0);
> +	if (!bridge)
> +		return bridge;

This returns NULL (0) where it previously returned -ENOMEM.  Callers
interpret zero as "success", so I think it should stil return -ENOMEM.

I tentatively changed it back to -ENOMEM locally, let me know if
that's wrong.

> +	pp->bridge = bridge;
> +
>  	ret = dw_pcie_get_resources(pci);
>  	if (ret)
>  		return ret;
> @@ -460,12 +466,6 @@ int dw_pcie_host_init(struct dw_pcie_rp *pp)
>  	if (ret)
>  		return ret;
>  
> -	bridge = devm_pci_alloc_host_bridge(dev, 0);
> -	if (!bridge)
> -		return -ENOMEM;
> -
> -	pp->bridge = bridge;
> -
>  	/* Get the I/O range from DT */
>  	win = resource_list_first_type(&bridge->windows, IORESOURCE_IO);
>  	if (win) {
> 
> -- 
> 2.34.1
>