Re: [PATCH v2 1/2] PCI: Export pci_parent_bus_reset() for drivers to use

[Leon Romanovsky <leon@kernel.org>]

On Tue, May 05, 2026 at 01:03:39AM +0100, Maciej W. Rozycki wrote:
> Export pci_parent_bus_reset() so that drivers do not duplicate it.  
> Document the interface.
> 
> Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
> ---
> Changes from v1, 
> <https://lore.kernel.org/r/alpine.DEB.2.21.2306200231020.14084@angie.orcam.me.uk/>:
> 
> - Reword function description so as to list the return values separately.
> ---
>  drivers/pci/pci.c   |   17 ++++++++++++++++-
>  include/linux/pci.h |    1 +
>  2 files changed, 17 insertions(+), 1 deletion(-)
> 
> linux-pci-parent-bus-reset-export.diff
> Index: linux-macro/drivers/pci/pci.c
> ===================================================================
> --- linux-macro.orig/drivers/pci/pci.c
> +++ linux-macro/drivers/pci/pci.c
> @@ -4833,7 +4833,21 @@ int pci_bridge_secondary_bus_reset(struc
>  }
>  EXPORT_SYMBOL_GPL(pci_bridge_secondary_bus_reset);
>  
> -static int pci_parent_bus_reset(struct pci_dev *dev, bool probe)
> +/**
> + * pci_parent_bus_reset - Reset a device via its upstream PCI bridge
> + * @dev: Device to reset.
> + * @probe: Only check if reset is possible if TRUE, actually reset if FALSE.
> + *
> + * Perform a device reset by requesting a secondary bus reset via the
> + * device's immediate upstream PCI bridge.  Return failure if the reset
> + * failed or it could not have been issued in the first place because
> + * the device is not on a secondary bus of any PCI bridge or it wouldn't
> + * be the only device reset.  If probing, then only verify whether it
> + * would be possible to issue a reset.
> + *
> + * Returns: 0 if successful or -ENOTTY otherwise.
> + */
> +int pci_parent_bus_reset(struct pci_dev *dev, bool probe)
>  {
>  	struct pci_dev *pdev;
>  
> @@ -4850,6 +4864,7 @@ static int pci_parent_bus_reset(struct p
>  
>  	return pci_bridge_secondary_bus_reset(dev->bus->self);
>  }
> +EXPORT_SYMBOL_GPL(pci_parent_bus_reset);

I wouldn't recommend doing this solely for hfi1. The driver is likely to be
removed or significantly changed soon.

https://lore.kernel.org/linux-rdma/177516078937.637585.1447184858924347033.stgit@awdrv-04.cornelisnetworks.com/

Thanks