1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Virtual EISA root driver.
4*4882a593Smuzhiyun * Acts as a placeholder if we don't have a proper EISA bridge.
5*4882a593Smuzhiyun *
6*4882a593Smuzhiyun * (C) 2003 Marc Zyngier <maz@wild-wind.fr.eu.org>
7*4882a593Smuzhiyun */
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun #include <linux/kernel.h>
10*4882a593Smuzhiyun #include <linux/platform_device.h>
11*4882a593Smuzhiyun #include <linux/eisa.h>
12*4882a593Smuzhiyun #include <linux/module.h>
13*4882a593Smuzhiyun #include <linux/moduleparam.h>
14*4882a593Smuzhiyun #include <linux/init.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun #if defined(CONFIG_ALPHA_JENSEN) || defined(CONFIG_EISA_VLB_PRIMING)
17*4882a593Smuzhiyun #define EISA_FORCE_PROBE_DEFAULT 1
18*4882a593Smuzhiyun #else
19*4882a593Smuzhiyun #define EISA_FORCE_PROBE_DEFAULT 0
20*4882a593Smuzhiyun #endif
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun static int force_probe = EISA_FORCE_PROBE_DEFAULT;
23*4882a593Smuzhiyun static void virtual_eisa_release (struct device *);
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun /* The default EISA device parent (virtual root device).
26*4882a593Smuzhiyun * Now use a platform device, since that's the obvious choice. */
27*4882a593Smuzhiyun
28*4882a593Smuzhiyun static struct platform_device eisa_root_dev = {
29*4882a593Smuzhiyun .name = "eisa",
30*4882a593Smuzhiyun .id = 0,
31*4882a593Smuzhiyun .dev = {
32*4882a593Smuzhiyun .release = virtual_eisa_release,
33*4882a593Smuzhiyun },
34*4882a593Smuzhiyun };
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun static struct eisa_root_device eisa_bus_root = {
37*4882a593Smuzhiyun .dev = &eisa_root_dev.dev,
38*4882a593Smuzhiyun .bus_base_addr = 0,
39*4882a593Smuzhiyun .res = &ioport_resource,
40*4882a593Smuzhiyun .slots = EISA_MAX_SLOTS,
41*4882a593Smuzhiyun .dma_mask = 0xffffffff,
42*4882a593Smuzhiyun };
43*4882a593Smuzhiyun
virtual_eisa_release(struct device * dev)44*4882a593Smuzhiyun static void virtual_eisa_release (struct device *dev)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun /* nothing really to do here */
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun
virtual_eisa_root_init(void)49*4882a593Smuzhiyun static int __init virtual_eisa_root_init (void)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun int r;
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun if ((r = platform_device_register (&eisa_root_dev)))
54*4882a593Smuzhiyun return r;
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun eisa_bus_root.force_probe = force_probe;
57*4882a593Smuzhiyun
58*4882a593Smuzhiyun dev_set_drvdata(&eisa_root_dev.dev, &eisa_bus_root);
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun if (eisa_root_register (&eisa_bus_root)) {
61*4882a593Smuzhiyun /* A real bridge may have been registered before
62*4882a593Smuzhiyun * us. So quietly unregister. */
63*4882a593Smuzhiyun platform_device_unregister (&eisa_root_dev);
64*4882a593Smuzhiyun return -1;
65*4882a593Smuzhiyun }
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun return 0;
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun module_param (force_probe, int, 0444);
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun device_initcall (virtual_eisa_root_init);
73