USB: serial: option: add Fibocom FM101-GL variant
[platform/kernel/linux-rpi.git] / drivers / pci / host-bridge.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Host bridge related code
4  */
5
6 #include <linux/kernel.h>
7 #include <linux/pci.h>
8 #include <linux/module.h>
9
10 #include "pci.h"
11
12 static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
13 {
14         while (bus->parent)
15                 bus = bus->parent;
16
17         return bus;
18 }
19
20 struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus)
21 {
22         struct pci_bus *root_bus = find_pci_root_bus(bus);
23
24         return to_pci_host_bridge(root_bus->bridge);
25 }
26 EXPORT_SYMBOL_GPL(pci_find_host_bridge);
27
28 struct device *pci_get_host_bridge_device(struct pci_dev *dev)
29 {
30         struct pci_bus *root_bus = find_pci_root_bus(dev->bus);
31         struct device *bridge = root_bus->bridge;
32
33         kobject_get(&bridge->kobj);
34         return bridge;
35 }
36
37 void  pci_put_host_bridge_device(struct device *dev)
38 {
39         kobject_put(&dev->kobj);
40 }
41
42 void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
43                                  void (*release_fn)(struct pci_host_bridge *),
44                                  void *release_data)
45 {
46         bridge->release_fn = release_fn;
47         bridge->release_data = release_data;
48 }
49 EXPORT_SYMBOL_GPL(pci_set_host_bridge_release);
50
51 void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
52                              struct resource *res)
53 {
54         struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
55         struct resource_entry *window;
56         resource_size_t offset = 0;
57
58         resource_list_for_each_entry(window, &bridge->windows) {
59                 if (resource_contains(window->res, res)) {
60                         offset = window->offset;
61                         break;
62                 }
63         }
64
65         region->start = res->start - offset;
66         region->end = res->end - offset;
67 }
68 EXPORT_SYMBOL(pcibios_resource_to_bus);
69
70 static bool region_contains(struct pci_bus_region *region1,
71                             struct pci_bus_region *region2)
72 {
73         return region1->start <= region2->start && region1->end >= region2->end;
74 }
75
76 void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
77                              struct pci_bus_region *region)
78 {
79         struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
80         struct resource_entry *window;
81         resource_size_t offset = 0;
82
83         resource_list_for_each_entry(window, &bridge->windows) {
84                 struct pci_bus_region bus_region;
85
86                 if (resource_type(res) != resource_type(window->res))
87                         continue;
88
89                 bus_region.start = window->res->start - window->offset;
90                 bus_region.end = window->res->end - window->offset;
91
92                 if (region_contains(&bus_region, region)) {
93                         offset = window->offset;
94                         break;
95                 }
96         }
97
98         res->start = region->start + offset;
99         res->end = region->end + offset;
100 }
101 EXPORT_SYMBOL(pcibios_bus_to_resource);