drivers/pcmcia/rsrc_iodyn.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * rsrc_iodyn.c -- Resource management routines for MEM-static sockets.
   4  *
   5  * The initial developer of the original code is David A. Hinds
   6  * <dahinds@users.sourceforge.net>.  Portions created by David A. Hinds
   7  * are Copyright (C) 1999 David A. Hinds.  All Rights Reserved.
   8  *
   9  * (C) 1999             David A. Hinds
  10  */
  11
  12 #include <linux/slab.h>
  13 #include <linux/module.h>
  14 #include <linux/kernel.h>
  15
  16 #include <pcmcia/ss.h>
  17 #include <pcmcia/cistpl.h>
  18 #include "cs_internal.h"
  19
  20
  21 struct pcmcia_align_data {
  22         unsigned long   mask;
  23         unsigned long   offset;
  24 };
  25
  26 static resource_size_t pcmcia_align(void *align_data,
  27                                 const struct resource *res,
  28                                 resource_size_t size, resource_size_t align)
  29 {
  30         struct pcmcia_align_data *data = align_data;
  31         resource_size_t start;
  32
  33         start = (res->start & ~data->mask) + data->offset;
  34         if (start < res->start)
  35                 start += data->mask + 1;
  36
  37 #ifdef CONFIG_X86
  38         if (res->flags & IORESOURCE_IO) {
  39                 if (start & 0x300)
  40                         start = (start + 0x3ff) & ~0x3ff;
  41         }
  42 #endif
  43
  44 #ifdef CONFIG_M68K
  45         if (res->flags & IORESOURCE_IO) {
  46                 if ((res->start + size - 1) >= 1024)
  47                         start = res->end;
  48         }
  49 #endif
  50
  51         return start;
  52 }
  53
  54
  55 static struct resource *__iodyn_find_io_region(struct pcmcia_socket *s,
  56                                         unsigned long base, int num,
  57                                         unsigned long align)
  58 {
  59         struct resource *res = pcmcia_make_resource(0, num, IORESOURCE_IO,
  60                                                 dev_name(&s->dev));
  61         struct pcmcia_align_data data;
  62         unsigned long min = base;
  63         int ret;
  64
  65         data.mask = align - 1;
  66         data.offset = base & data.mask;
  67
  68 #ifdef CONFIG_PCI
  69         if (s->cb_dev) {
  70                 ret = pci_bus_alloc_resource(s->cb_dev->bus, res, num, 1,
  71                                              min, 0, pcmcia_align, &data);
  72         } else
  73 #endif
  74                 ret = allocate_resource(&ioport_resource, res, num, min, ~0UL,
  75                                         1, pcmcia_align, &data);
  76
  77         if (ret != 0) {
  78                 kfree(res);
  79                 res = NULL;
  80         }
  81         return res;
  82 }
  83
  84 static int iodyn_find_io(struct pcmcia_socket *s, unsigned int attr,
  85                         unsigned int *base, unsigned int num,
  86                         unsigned int align, struct resource **parent)
  87 {
  88         int i, ret = 0;
  89
  90         /* Check for an already-allocated window that must conflict with
  91          * what was asked for.  It is a hack because it does not catch all
  92          * potential conflicts, just the most obvious ones.
  93          */
  94         for (i = 0; i < MAX_IO_WIN; i++) {
  95                 if (!s->io[i].res)
  96                         continue;
  97
  98                 if (!*base)
  99                         continue;
 100
 101                 if ((s->io[i].res->start & (align-1)) == *base)
 102                         return -EBUSY;
 103         }
 104
 105         for (i = 0; i < MAX_IO_WIN; i++) {
 106                 struct resource *res = s->io[i].res;
 107                 unsigned int try;
 108
 109                 if (res && (res->flags & IORESOURCE_BITS) !=
 110                         (attr & IORESOURCE_BITS))
 111                         continue;
 112
 113                 if (!res) {
 114                         if (align == 0)
 115                                 align = 0x10000;
 116
 117                         res = s->io[i].res = __iodyn_find_io_region(s, *base,
 118                                                                 num, align);
 119                         if (!res)
 120                                 return -EINVAL;
 121
 122                         *base = res->start;
 123                         s->io[i].res->flags =
 124                                 ((res->flags & ~IORESOURCE_BITS) |
 125                                         (attr & IORESOURCE_BITS));
 126                         s->io[i].InUse = num;
 127                         *parent = res;
 128                         return 0;
 129                 }
 130
 131                 /* Try to extend top of window */
 132                 try = res->end + 1;
 133                 if ((*base == 0) || (*base == try)) {
 134                         if (adjust_resource(s->io[i].res, res->start,
 135                                             resource_size(res) + num))
 136                                 continue;
 137                         *base = try;
 138                         s->io[i].InUse += num;
 139                         *parent = res;
 140                         return 0;
 141                 }
 142
 143                 /* Try to extend bottom of window */
 144                 try = res->start - num;
 145                 if ((*base == 0) || (*base == try)) {
 146                         if (adjust_resource(s->io[i].res,
 147                                             res->start - num,
 148                                             resource_size(res) + num))
 149                                 continue;
 150                         *base = try;
 151                         s->io[i].InUse += num;
 152                         *parent = res;
 153                         return 0;
 154                 }
 155         }
 156
 157         return -EINVAL;
 158 }
 159
 160
 161 struct pccard_resource_ops pccard_iodyn_ops = {
 162         .validate_mem = NULL,
 163         .find_io = iodyn_find_io,
 164         .find_mem = NULL,
 165         .init = static_init,
 166         .exit = NULL,
 167 };
 168 EXPORT_SYMBOL(pccard_iodyn_ops);