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Subject: Re: [PATCH] [POWERPC] Make pci_bus_to_host()'s struct pci_bus *
	argument const
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Trent Piepho <tpiepho@freescale.com>
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Date: Wed, 09 Apr 2008 13:44:16 +1000
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On Tue, 2008-04-08 at 19:19 -0700, Trent Piepho wrote:
> Why?  Because:
> A) It's not modified and so it can be made const.  const is good.
> B) If one has a function that was given a const pci_bus pointer and you
> want to get a pointer to its pci_controller, you'll get a warning from gcc
> when you use pci_bus_to_host().  This is the right way to stop that
> warning.
> 
> Signed-off-by: Trent Piepho <tpiepho@freescale.com>

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> ---
>  include/asm-powerpc/pci-bridge.h |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/include/asm-powerpc/pci-bridge.h b/include/asm-powerpc/pci-bridge.h
> index e5802c6..b95d033 100644
> --- a/include/asm-powerpc/pci-bridge.h
> +++ b/include/asm-powerpc/pci-bridge.h
> @@ -117,7 +117,7 @@ struct pci_controller {
>  
>  #ifndef CONFIG_PPC64
>  
> -static inline struct pci_controller *pci_bus_to_host(struct pci_bus *bus)
> +static inline struct pci_controller *pci_bus_to_host(const struct pci_bus *bus)
>  {
>  	return bus->sysdata;
>  }
> @@ -235,7 +235,7 @@ extern void pcibios_fixup_new_pci_devices(struct pci_bus *bus);
>  
>  extern int pcibios_remove_root_bus(struct pci_controller *phb);
>  
> -static inline struct pci_controller *pci_bus_to_host(struct pci_bus *bus)
> +static inline struct pci_controller *pci_bus_to_host(const struct pci_bus *bus)
>  {
>  	struct device_node *busdn = bus->sysdata;
>