tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include <linux/kernel.h>
2#include <linux/export.h>
3#include <linux/of.h>
4#include <linux/of_pci.h>
5#include <asm/prom.h>
6
7static inline int __of_pci_pci_compare(struct device_node *node,
8 unsigned int data)
9{
10 int devfn;
11
12 devfn = of_pci_get_devfn(node);
13 if (devfn < 0)
14 return 0;
15
16 return devfn == data;
17}
18
19struct device_node *of_pci_find_child_device(struct device_node *parent,
20 unsigned int devfn)
21{
22 struct device_node *node, *node2;
23
24 for_each_child_of_node(parent, node) {
25 if (__of_pci_pci_compare(node, devfn))
26 return node;
27 /*
28 * Some OFs create a parent node "multifunc-device" as
29 * a fake root for all functions of a multi-function
30 * device we go down them as well.
31 */
32 if (!strcmp(node->name, "multifunc-device")) {
33 for_each_child_of_node(node, node2) {
34 if (__of_pci_pci_compare(node2, devfn)) {
35 of_node_put(node);
36 return node2;
37 }
38 }
39 }
40 }
41 return NULL;
42}
43EXPORT_SYMBOL_GPL(of_pci_find_child_device);
44
45/**
46 * of_pci_get_devfn() - Get device and function numbers for a device node
47 * @np: device node
48 *
49 * Parses a standard 5-cell PCI resource and returns an 8-bit value that can
50 * be passed to the PCI_SLOT() and PCI_FUNC() macros to extract the device
51 * and function numbers respectively. On error a negative error code is
52 * returned.
53 */
54int of_pci_get_devfn(struct device_node *np)
55{
56 unsigned int size;
57 const __be32 *reg;
58
59 reg = of_get_property(np, "reg", &size);
60
61 if (!reg || size < 5 * sizeof(__be32))
62 return -EINVAL;
63
64 return (be32_to_cpup(reg) >> 8) & 0xff;
65}
66EXPORT_SYMBOL_GPL(of_pci_get_devfn);
67
68/**
69 * of_pci_parse_bus_range() - parse the bus-range property of a PCI device
70 * @node: device node
71 * @res: address to a struct resource to return the bus-range
72 *
73 * Returns 0 on success or a negative error-code on failure.
74 */
75int of_pci_parse_bus_range(struct device_node *node, struct resource *res)
76{
77 const __be32 *values;
78 int len;
79
80 values = of_get_property(node, "bus-range", &len);
81 if (!values || len < sizeof(*values) * 2)
82 return -EINVAL;
83
84 res->name = node->name;
85 res->start = be32_to_cpup(values++);
86 res->end = be32_to_cpup(values);
87 res->flags = IORESOURCE_BUS;
88
89 return 0;
90}
91EXPORT_SYMBOL_GPL(of_pci_parse_bus_range);