of/pci: Add of_pci_get_devfn() function

This function can be used to parse the device and function number from a
standard 5-cell PCI resource. PCI_SLOT() and PCI_FUNC() can be used on
the returned value obtain the device and function numbers respectively.

Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
This commit is contained in:
Thierry Reding 2013-05-16 17:55:18 +02:00 committed by Jason Cooper
parent 29b635c00f
commit 45ab9702fb
2 changed files with 30 additions and 5 deletions

View File

@ -5,14 +5,15 @@
#include <asm/prom.h>
static inline int __of_pci_pci_compare(struct device_node *node,
unsigned int devfn)
unsigned int data)
{
unsigned int size;
const __be32 *reg = of_get_property(node, "reg", &size);
int devfn;
if (!reg || size < 5 * sizeof(__be32))
devfn = of_pci_get_devfn(node);
if (devfn < 0)
return 0;
return ((be32_to_cpup(&reg[0]) >> 8) & 0xff) == devfn;
return devfn == data;
}
struct device_node *of_pci_find_child_device(struct device_node *parent,
@ -40,3 +41,26 @@ struct device_node *of_pci_find_child_device(struct device_node *parent,
return NULL;
}
EXPORT_SYMBOL_GPL(of_pci_find_child_device);
/**
* of_pci_get_devfn() - Get device and function numbers for a device node
* @np: device node
*
* Parses a standard 5-cell PCI resource and returns an 8-bit value that can
* be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device
* and function numbers respectively. On error a negative error code is
* returned.
*/
int of_pci_get_devfn(struct device_node *np)
{
unsigned int size;
const __be32 *reg;
reg = of_get_property(np, "reg", &size);
if (!reg || size < 5 * sizeof(__be32))
return -EINVAL;
return (be32_to_cpup(reg) >> 8) & 0xff;
}
EXPORT_SYMBOL_GPL(of_pci_get_devfn);

View File

@ -10,5 +10,6 @@ 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,
unsigned int devfn);
int of_pci_get_devfn(struct device_node *np);
#endif