Merge Linux 2.6.23
[sfrench/cifs-2.6.git] / drivers / mtd / maps / physmap_of.c
1 /*
2  * Normal mappings of chips in physical memory for OF devices
3  *
4  * Copyright (C) 2006 MontaVista Software Inc.
5  * Author: Vitaly Wool <vwool@ru.mvista.com>
6  *
7  * This program is free software; you can redistribute  it and/or modify it
8  * under  the terms of  the GNU General  Public License as published by the
9  * Free Software Foundation;  either version 2 of the  License, or (at your
10  * option) any later version.
11  */
12
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/device.h>
19 #include <linux/mtd/mtd.h>
20 #include <linux/mtd/map.h>
21 #include <linux/mtd/partitions.h>
22 #include <linux/mtd/physmap.h>
23 #include <asm/io.h>
24 #include <asm/prom.h>
25 #include <asm/of_device.h>
26 #include <asm/of_platform.h>
27
28 struct physmap_flash_info {
29         struct mtd_info         *mtd;
30         struct map_info         map;
31         struct resource         *res;
32 #ifdef CONFIG_MTD_PARTITIONS
33         int                     nr_parts;
34         struct mtd_partition    *parts;
35 #endif
36 };
37
38 static const char *rom_probe_types[] = { "cfi_probe", "jedec_probe", "map_rom", NULL };
39 #ifdef CONFIG_MTD_PARTITIONS
40 static const char *part_probe_types[] = { "cmdlinepart", "RedBoot", NULL };
41 #endif
42
43 #ifdef CONFIG_MTD_PARTITIONS
44 static int parse_flash_partitions(struct device_node *node,
45                 struct mtd_partition **parts)
46 {
47         int i, plen, retval = -ENOMEM;
48         const  u32  *part;
49         const  char *name;
50
51         part = of_get_property(node, "partitions", &plen);
52         if (part == NULL)
53                 goto err;
54
55         retval = plen / (2 * sizeof(u32));
56         *parts = kzalloc(retval * sizeof(struct mtd_partition), GFP_KERNEL);
57         if (*parts == NULL) {
58                 printk(KERN_ERR "Can't allocate the flash partition data!\n");
59                 goto err;
60         }
61
62         name = of_get_property(node, "partition-names", &plen);
63
64         for (i = 0; i < retval; i++) {
65                 (*parts)[i].offset = *part++;
66                 (*parts)[i].size   = *part & ~1;
67                 if (*part++ & 1) /* bit 0 set signifies read only partition */
68                         (*parts)[i].mask_flags = MTD_WRITEABLE;
69
70                 if (name != NULL && plen > 0) {
71                         int len = strlen(name) + 1;
72
73                         (*parts)[i].name = (char *)name;
74                         plen -= len;
75                         name += len;
76                 } else
77                         (*parts)[i].name = "unnamed";
78         }
79 err:
80         return retval;
81 }
82 #endif
83
84 static int of_physmap_remove(struct of_device *dev)
85 {
86         struct physmap_flash_info *info;
87
88         info = dev_get_drvdata(&dev->dev);
89         if (info == NULL)
90                 return 0;
91         dev_set_drvdata(&dev->dev, NULL);
92
93         if (info->mtd != NULL) {
94 #ifdef CONFIG_MTD_PARTITIONS
95                 if (info->nr_parts) {
96                         del_mtd_partitions(info->mtd);
97                         kfree(info->parts);
98                 } else {
99                         del_mtd_device(info->mtd);
100                 }
101 #else
102                 del_mtd_device(info->mtd);
103 #endif
104                 map_destroy(info->mtd);
105         }
106
107         if (info->map.virt != NULL)
108                 iounmap(info->map.virt);
109
110         if (info->res != NULL) {
111                 release_resource(info->res);
112                 kfree(info->res);
113         }
114
115         return 0;
116 }
117
118 static int __devinit of_physmap_probe(struct of_device *dev, const struct of_device_id *match)
119 {
120         struct device_node *dp = dev->node;
121         struct resource res;
122         struct physmap_flash_info *info;
123         const char **probe_type;
124         const char *of_probe;
125         const u32 *width;
126         int err;
127
128
129         if (of_address_to_resource(dp, 0, &res)) {
130                 dev_err(&dev->dev, "Can't get the flash mapping!\n");
131                 err = -EINVAL;
132                 goto err_out;
133         }
134
135         dev_dbg(&dev->dev, "physmap flash device: %.8llx at %.8llx\n",
136             (unsigned long long)res.end - res.start + 1,
137             (unsigned long long)res.start);
138
139         info = kzalloc(sizeof(struct physmap_flash_info), GFP_KERNEL);
140         if (info == NULL) {
141                 err = -ENOMEM;
142                 goto err_out;
143         }
144
145         dev_set_drvdata(&dev->dev, info);
146
147         info->res = request_mem_region(res.start, res.end - res.start + 1,
148                         dev->dev.bus_id);
149         if (info->res == NULL) {
150                 dev_err(&dev->dev, "Could not reserve memory region\n");
151                 err = -ENOMEM;
152                 goto err_out;
153         }
154
155         width = of_get_property(dp, "bank-width", NULL);
156         if (width == NULL) {
157                 dev_err(&dev->dev, "Can't get the flash bank width!\n");
158                 err = -EINVAL;
159                 goto err_out;
160         }
161
162         info->map.name = dev->dev.bus_id;
163         info->map.phys = res.start;
164         info->map.size = res.end - res.start + 1;
165         info->map.bankwidth = *width;
166
167         info->map.virt = ioremap(info->map.phys, info->map.size);
168         if (info->map.virt == NULL) {
169                 dev_err(&dev->dev, "Failed to ioremap flash region\n");
170                 err = EIO;
171                 goto err_out;
172         }
173
174         simple_map_init(&info->map);
175
176         of_probe = of_get_property(dp, "probe-type", NULL);
177         if (of_probe == NULL) {
178                 probe_type = rom_probe_types;
179                 for (; info->mtd == NULL && *probe_type != NULL; probe_type++)
180                         info->mtd = do_map_probe(*probe_type, &info->map);
181         } else if (!strcmp(of_probe, "CFI"))
182                 info->mtd = do_map_probe("cfi_probe", &info->map);
183         else if (!strcmp(of_probe, "JEDEC"))
184                 info->mtd = do_map_probe("jedec_probe", &info->map);
185         else {
186                 if (strcmp(of_probe, "ROM"))
187                         dev_dbg(&dev->dev, "map_probe: don't know probe type "
188                         "'%s', mapping as rom\n", of_probe);
189                 info->mtd = do_map_probe("mtd_rom", &info->map);
190         }
191         if (info->mtd == NULL) {
192                 dev_err(&dev->dev, "map_probe failed\n");
193                 err = -ENXIO;
194                 goto err_out;
195         }
196         info->mtd->owner = THIS_MODULE;
197
198 #ifdef CONFIG_MTD_PARTITIONS
199         err = parse_mtd_partitions(info->mtd, part_probe_types, &info->parts, 0);
200         if (err > 0) {
201                 add_mtd_partitions(info->mtd, info->parts, err);
202         } else if ((err = parse_flash_partitions(dp, &info->parts)) > 0) {
203                 dev_info(&dev->dev, "Using OF partition information\n");
204                 add_mtd_partitions(info->mtd, info->parts, err);
205                 info->nr_parts = err;
206         } else
207 #endif
208
209         add_mtd_device(info->mtd);
210         return 0;
211
212 err_out:
213         of_physmap_remove(dev);
214         return err;
215 }
216
217 static struct of_device_id of_physmap_match[] = {
218         {
219                 .type           = "rom",
220                 .compatible     = "direct-mapped"
221         },
222         { },
223 };
224
225 MODULE_DEVICE_TABLE(of, of_physmap_match);
226
227
228 static struct of_platform_driver of_physmap_flash_driver = {
229         .name           = "physmap-flash",
230         .match_table    = of_physmap_match,
231         .probe          = of_physmap_probe,
232         .remove         = of_physmap_remove,
233 };
234
235 static int __init of_physmap_init(void)
236 {
237         return of_register_platform_driver(&of_physmap_flash_driver);
238 }
239
240 static void __exit of_physmap_exit(void)
241 {
242         of_unregister_platform_driver(&of_physmap_flash_driver);
243 }
244
245 module_init(of_physmap_init);
246 module_exit(of_physmap_exit);
247
248 MODULE_LICENSE("GPL");
249 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
250 MODULE_DESCRIPTION("Configurable MTD map driver for OF");