1// SPDX-License-Identifier: GPL-2.0
2#if defined(__i386__) || defined(__x86_64__)
3
4#include <helpers/helpers.h>
5
6/*
7 * pci_acc_init
8 *
9 * PCI access helper function depending on libpci
10 *
11 * **pacc : if a valid pci_dev is returned
12 *         *pacc must be passed to pci_acc_cleanup to free it
13 *
14 * domain: domain
15 * bus:    bus
16 * slot:   slot
17 * func:   func
18 * vendor: vendor
19 * device: device
20 * Pass -1 for one of the six above to match any
21 *
22 * Returns :
23 * struct pci_dev which can be used with pci_{read,write}_* functions
24 *                to access the PCI config space of matching pci devices
25 */
26struct pci_dev *pci_acc_init(struct pci_access **pacc, int domain, int bus,
27			     int slot, int func, int vendor, int dev)
28{
29	struct pci_filter filter_nb_link;
30	struct pci_dev *device;
31
32	*pacc = pci_alloc();
33	if (*pacc == NULL)
34		return NULL;
35
36	pci_filter_init(*pacc, &filter_nb_link);
37	filter_nb_link.domain	= domain;
38	filter_nb_link.bus	= bus;
39	filter_nb_link.slot	= slot;
40	filter_nb_link.func	= func;
41	filter_nb_link.vendor	= vendor;
42	filter_nb_link.device	= dev;
43
44	pci_init(*pacc);
45	pci_scan_bus(*pacc);
46
47	for (device = (*pacc)->devices; device; device = device->next) {
48		if (pci_filter_match(&filter_nb_link, device))
49			return device;
50	}
51	pci_cleanup(*pacc);
52	return NULL;
53}
54
55/* Typically one wants to get a specific slot(device)/func of the root domain
56   and bus */
57struct pci_dev *pci_slot_func_init(struct pci_access **pacc, int slot,
58				       int func)
59{
60	return pci_acc_init(pacc, 0, 0, slot, func, -1, -1);
61}
62
63#endif /* defined(__i386__) || defined(__x86_64__) */
64