Re: [PATCH] OF: PCI: const usage needed by MIPS

[David Daney <ddaney.cavm@gmail.com>]

On 04/30/2012 10:46 AM, John Crispin wrote:
> On MIPS we want to call of_irq_map_pci from inside
>
> arch/mips/include/asm/pci.h:extern int pcibios_map_irq(
> 				const struct pci_dev *dev, u8 slot, u8 pin);
>
> For this to work we need to change several functions to const usage.

I think there is a mismatch on this throughout the kernel.

Properly fixing it requires touching many more places than these. 
Although I haven't tried it, I wouldn't be surprised if doing this 
caused warnings to appear in non-MIPS code.

Ralf had a patch at one point that tried to make this consistent 
tree-wide, but it is not yet applied.

David Daney

>
> Signed-off-by: John Crispin<blogic@openwrt.org>
> Cc: linux-pci@vger.kernel.org
> Cc: devicetree-discuss@lists.ozlabs.org
> Cc: linux-mips@linux-mips.org
> ---
> I am not sure which tree this should go via. Grant, can you take it ?
>
>   drivers/of/of_pci_irq.c |    2 +-
>   drivers/pci/pci.c       |    2 +-
>   include/linux/of_pci.h  |    2 +-
>   include/linux/pci.h     |    5 +++--
>   4 files changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/of/of_pci_irq.c b/drivers/of/of_pci_irq.c
> index 9312516..6770538 100644
> --- a/drivers/of/of_pci_irq.c
> +++ b/drivers/of/of_pci_irq.c
> @@ -15,7 +15,7 @@
>    * PCI tree until an device-node is found, at which point it will finish
>    * resolving using the OF tree walking.
>    */
> -int of_irq_map_pci(struct pci_dev *pdev, struct of_irq *out_irq)
> +int of_irq_map_pci(const struct pci_dev *pdev, struct of_irq *out_irq)
>   {
>   	struct device_node *dn, *ppnode;
>   	struct pci_dev *ppdev;
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index d20f133..4c79586 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -2363,7 +2363,7 @@ void pci_enable_acs(struct pci_dev *dev)
>    * number is always 0 (see the Implementation Note in section 2.2.8.1 of
>    * the PCI Express Base Specification, Revision 2.1)
>    */
> -u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin)
> +u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin)
>   {
>   	int slot;
>
> diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h
> index f93e217..bb115de 100644
> --- a/include/linux/of_pci.h
> +++ b/include/linux/of_pci.h
> @@ -5,7 +5,7 @@
>
>   struct pci_dev;
>   struct of_irq;
> -int of_irq_map_pci(struct pci_dev *pdev, struct of_irq *out_irq);
> +int of_irq_map_pci(const struct pci_dev *pdev, struct of_irq *out_irq);
>
>   struct device_node;
>   struct device_node *of_pci_find_child_device(struct device_node *parent,
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index e444f5b..3bbc77e 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -680,7 +680,7 @@ int __must_check pci_bus_add_device(struct pci_dev *dev);
>   void pci_read_bridge_bases(struct pci_bus *child);
>   struct resource *pci_find_parent_resource(const struct pci_dev *dev,
>   					  struct resource *res);
> -u8 pci_swizzle_interrupt_pin(struct pci_dev *dev, u8 pin);
> +u8 pci_swizzle_interrupt_pin(const struct pci_dev *dev, u8 pin);
>   int pci_get_interrupt_pin(struct pci_dev *dev, struct pci_dev **bridge);
>   u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp);
>   extern struct pci_dev *pci_dev_get(struct pci_dev *dev);
> @@ -1685,7 +1685,8 @@ extern void pci_release_bus_of_node(struct pci_bus *bus);
>   /* Arch may override this (weak) */
>   extern struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus);
>
> -static inline struct device_node *pci_device_to_OF_node(struct pci_dev *pdev)
> +static inline struct device_node *
> +pci_device_to_OF_node(const struct pci_dev *pdev)
>   {
>   	return pdev ? pdev->dev.of_node : NULL;
>   }