Re: [PATCH 3/6] PCI: introduce pci_trim_stale_devices()

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Tuesday, June 25, 2013 07:22:07 PM Mika Westerberg wrote:
> From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
> 
> The new function stops and removes the device if it doesn't respond.
> If the device responds and it's a bus we apply the function to all
> subdevices recursively.
> 
> It's useful for hotplug bus check case, when you need drop all unplugged
> devices before looking for new ones.
> 
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

I think it'd be better to fold this into [4/6].  This way it would be clearer
what that patch did.

Thanks,
Rafael


> ---
>  drivers/pci/remove.c | 20 ++++++++++++++++++++
>  include/linux/pci.h  |  1 +
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
> index 8fc54b7..77b7a64 100644
> --- a/drivers/pci/remove.c
> +++ b/drivers/pci/remove.c
> @@ -112,6 +112,26 @@ void pci_stop_and_remove_bus_device(struct pci_dev *dev)
>  }
>  EXPORT_SYMBOL(pci_stop_and_remove_bus_device);
>  
> +/**
> + * pci_trim_stale_devices - remove stale device or any stale child
> + */
> +void pci_trim_stale_devices(struct pci_dev *dev)
> +{
> +	struct pci_bus *bus = dev->subordinate;
> +	struct pci_dev *child, *tmp;
> +	bool alive;
> +	u32 l;
> +
> +	/* check if the device responds */
> +	alive = pci_bus_read_dev_vendor_id(dev->bus, dev->devfn, &l, 0);
> +	if (!alive)
> +		pci_stop_and_remove_bus_device(dev);
> +
> +	if (alive && bus)
> +		list_for_each_entry_safe(child, tmp, &bus->devices, bus_list)
> +			pci_trim_stale_devices(child);
> +}
> +
>  void pci_stop_root_bus(struct pci_bus *bus)
>  {
>  	struct pci_dev *child, *tmp;
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 3a24e4f..8f6e7a0 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -754,6 +754,7 @@ struct pci_dev *pci_dev_get(struct pci_dev *dev);
>  void pci_dev_put(struct pci_dev *dev);
>  void pci_remove_bus(struct pci_bus *b);
>  void pci_stop_and_remove_bus_device(struct pci_dev *dev);
> +void pci_trim_stale_devices(struct pci_dev *dev);
>  void pci_stop_root_bus(struct pci_bus *bus);
>  void pci_remove_root_bus(struct pci_bus *bus);
>  void pci_setup_cardbus(struct pci_bus *bus);
> 
-- 
I speak only for myself.
Rafael J. Wysocki, Intel Open Source Technology Center.