xref: /linux/drivers/pcmcia/rsrc_iodyn.c (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
1 /*
2  * rsrc_iodyn.c -- Resource management routines for MEM-static sockets.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 as
6  * published by the Free Software Foundation.
7  *
8  * The initial developer of the original code is David A. Hinds
9  * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
10  * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
11  *
12  * (C) 1999		David A. Hinds
13  */
14 
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/kernel.h>
18 
19 #include <pcmcia/ss.h>
20 #include <pcmcia/cistpl.h>
21 #include "cs_internal.h"
22 
23 
24 struct pcmcia_align_data {
25 	unsigned long	mask;
26 	unsigned long	offset;
27 };
28 
29 static resource_size_t pcmcia_align(void *align_data,
30 				const struct resource *res,
31 				resource_size_t size, resource_size_t align)
32 {
33 	struct pcmcia_align_data *data = align_data;
34 	resource_size_t start;
35 
36 	start = (res->start & ~data->mask) + data->offset;
37 	if (start < res->start)
38 		start += data->mask + 1;
39 
40 #ifdef CONFIG_X86
41 	if (res->flags & IORESOURCE_IO) {
42 		if (start & 0x300)
43 			start = (start + 0x3ff) & ~0x3ff;
44 	}
45 #endif
46 
47 #ifdef CONFIG_M68K
48 	if (res->flags & IORESOURCE_IO) {
49 		if ((res->start + size - 1) >= 1024)
50 			start = res->end;
51 	}
52 #endif
53 
54 	return start;
55 }
56 
57 
58 static struct resource *__iodyn_find_io_region(struct pcmcia_socket *s,
59 					unsigned long base, int num,
60 					unsigned long align)
61 {
62 	struct resource *res = pcmcia_make_resource(0, num, IORESOURCE_IO,
63 						dev_name(&s->dev));
64 	struct pcmcia_align_data data;
65 	unsigned long min = base;
66 	int ret;
67 
68 	data.mask = align - 1;
69 	data.offset = base & data.mask;
70 
71 #ifdef CONFIG_PCI
72 	if (s->cb_dev) {
73 		ret = pci_bus_alloc_resource(s->cb_dev->bus, res, num, 1,
74 					     min, 0, pcmcia_align, &data);
75 	} else
76 #endif
77 		ret = allocate_resource(&ioport_resource, res, num, min, ~0UL,
78 					1, pcmcia_align, &data);
79 
80 	if (ret != 0) {
81 		kfree(res);
82 		res = NULL;
83 	}
84 	return res;
85 }
86 
87 static int iodyn_find_io(struct pcmcia_socket *s, unsigned int attr,
88 			unsigned int *base, unsigned int num,
89 			unsigned int align, struct resource **parent)
90 {
91 	int i, ret = 0;
92 
93 	/* Check for an already-allocated window that must conflict with
94 	 * what was asked for.  It is a hack because it does not catch all
95 	 * potential conflicts, just the most obvious ones.
96 	 */
97 	for (i = 0; i < MAX_IO_WIN; i++) {
98 		if (!s->io[i].res)
99 			continue;
100 
101 		if (!*base)
102 			continue;
103 
104 		if ((s->io[i].res->start & (align-1)) == *base)
105 			return -EBUSY;
106 	}
107 
108 	for (i = 0; i < MAX_IO_WIN; i++) {
109 		struct resource *res = s->io[i].res;
110 		unsigned int try;
111 
112 		if (res && (res->flags & IORESOURCE_BITS) !=
113 			(attr & IORESOURCE_BITS))
114 			continue;
115 
116 		if (!res) {
117 			if (align == 0)
118 				align = 0x10000;
119 
120 			res = s->io[i].res = __iodyn_find_io_region(s, *base,
121 								num, align);
122 			if (!res)
123 				return -EINVAL;
124 
125 			*base = res->start;
126 			s->io[i].res->flags =
127 				((res->flags & ~IORESOURCE_BITS) |
128 					(attr & IORESOURCE_BITS));
129 			s->io[i].InUse = num;
130 			*parent = res;
131 			return 0;
132 		}
133 
134 		/* Try to extend top of window */
135 		try = res->end + 1;
136 		if ((*base == 0) || (*base == try)) {
137 			if (adjust_resource(s->io[i].res, res->start,
138 					    resource_size(res) + num))
139 				continue;
140 			*base = try;
141 			s->io[i].InUse += num;
142 			*parent = res;
143 			return 0;
144 		}
145 
146 		/* Try to extend bottom of window */
147 		try = res->start - num;
148 		if ((*base == 0) || (*base == try)) {
149 			if (adjust_resource(s->io[i].res,
150 					    res->start - num,
151 					    resource_size(res) + num))
152 				continue;
153 			*base = try;
154 			s->io[i].InUse += num;
155 			*parent = res;
156 			return 0;
157 		}
158 	}
159 
160 	return -EINVAL;
161 }
162 
163 
164 struct pccard_resource_ops pccard_iodyn_ops = {
165 	.validate_mem = NULL,
166 	.find_io = iodyn_find_io,
167 	.find_mem = NULL,
168 	.init = static_init,
169 	.exit = NULL,
170 };
171 EXPORT_SYMBOL(pccard_iodyn_ops);
172