1 /* drivers/mtd/maps/plat-ram.c
3 * (c) 2004-2005 Simtec Electronics
4 * http://www.simtec.co.uk/products/SWLINUX/
5 * Ben Dooks <ben@simtec.co.uk>
7 * Generic platfrom device based RAM map
9 * $Id: plat-ram.c,v 1.3 2005/03/19 22:41:27 gleixner Exp $
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include <linux/module.h>
27 #include <linux/types.h>
28 #include <linux/init.h>
29 #include <linux/kernel.h>
30 #include <linux/string.h>
31 #include <linux/ioport.h>
32 #include <linux/device.h>
33 #include <linux/slab.h>
35 #include <linux/mtd/mtd.h>
36 #include <linux/mtd/map.h>
37 #include <linux/mtd/partitions.h>
38 #include <linux/mtd/plat-ram.h>
42 /* private structure for each mtd platform ram device created */
48 struct mtd_partition *partitions;
49 struct resource *area;
50 struct platdata_mtd_ram *pdata;
55 * device private data to struct platram_info conversion
58 static inline struct platram_info *to_platram_info(struct device *dev)
60 return (struct platram_info *)dev_get_drvdata(dev);
65 * call the platform device's set rw/ro control
71 static inline void platram_setrw(struct platram_info *info, int to)
73 if (info->pdata == NULL)
76 if (info->pdata->set_rw != NULL)
77 (info->pdata->set_rw)(info->dev, to);
82 * called to remove the device from the driver's control
85 static int platram_remove(struct device *dev)
87 struct platram_info *info = to_platram_info(dev);
89 dev_set_drvdata(dev, NULL);
91 dev_dbg(dev, "removing device\n");
97 #ifdef CONFIG_MTD_PARTITIONS
98 if (info->partitions) {
99 del_mtd_partitions(info->mtd);
100 kfree(info->partitions);
103 del_mtd_device(info->mtd);
104 map_destroy(info->mtd);
107 /* ensure ram is left read-only */
109 platram_setrw(info, PLATRAM_RO);
111 /* release resources */
114 release_resource(info->area);
118 if (info->map.virt != NULL)
119 iounmap(info->map.virt);
128 * called from device drive system when a device matching our
132 static int platram_probe(struct device *dev)
134 struct platform_device *pd = to_platform_device(dev);
135 struct platdata_mtd_ram *pdata;
136 struct platram_info *info;
137 struct resource *res;
140 dev_dbg(dev, "probe entered\n");
142 if (dev->platform_data == NULL) {
143 dev_err(dev, "no platform data supplied\n");
148 pdata = dev->platform_data;
150 info = kmalloc(sizeof(*info), GFP_KERNEL);
152 dev_err(dev, "no memory for flash info\n");
157 memset(info, 0, sizeof(*info));
158 dev_set_drvdata(dev, info);
163 /* get the resource for the memory mapping */
165 res = platform_get_resource(pd, IORESOURCE_MEM, 0);
168 dev_err(dev, "no memory resource specified\n");
173 dev_dbg(dev, "got platform resource %p (0x%lx)\n", res, res->start);
175 /* setup map parameters */
177 info->map.phys = res->start;
178 info->map.size = (res->end - res->start) + 1;
179 info->map.name = pdata->mapname != NULL ? pdata->mapname : pd->name;
180 info->map.bankwidth = pdata->bankwidth;
182 /* register our usage of the memory area */
184 info->area = request_mem_region(res->start, info->map.size, pd->name);
185 if (info->area == NULL) {
186 dev_err(dev, "failed to request memory region\n");
191 /* remap the memory area */
193 info->map.virt = ioremap(res->start, info->map.size);
194 dev_dbg(dev, "virt %p, %lu bytes\n", info->map.virt, info->map.size);
196 if (info->map.virt == NULL) {
197 dev_err(dev, "failed to ioremap() region\n");
202 simple_map_init(&info->map);
204 dev_dbg(dev, "initialised map, probing for mtd\n");
206 /* probe for the right mtd map driver */
208 info->mtd = do_map_probe("map_ram" , &info->map);
209 if (info->mtd == NULL) {
210 dev_err(dev, "failed to probe for map_ram\n");
215 info->mtd->owner = THIS_MODULE;
217 platram_setrw(info, PLATRAM_RW);
219 /* check to see if there are any available partitions, or wether
220 * to add this device whole */
222 #ifdef CONFIG_MTD_PARTITIONS
223 if (pdata->nr_partitions > 0) {
224 const char **probes = { NULL };
227 probes = (const char **)pdata->probes;
229 err = parse_mtd_partitions(info->mtd, probes,
230 &info->partitions, 0);
232 err = add_mtd_partitions(info->mtd, info->partitions,
236 #endif /* CONFIG_MTD_PARTITIONS */
238 if (add_mtd_device(info->mtd)) {
239 dev_err(dev, "add_mtd_device() failed\n");
243 dev_info(dev, "registered mtd device\n");
252 /* device driver info */
254 static struct device_driver platram_driver = {
256 .bus = &platform_bus_type,
257 .probe = platram_probe,
258 .remove = platram_remove,
261 /* module init/exit */
263 static int __init platram_init(void)
265 printk("Generic platform RAM MTD, (c) 2004 Simtec Electronics\n");
266 return driver_register(&platram_driver);
269 static void __exit platram_exit(void)
271 driver_unregister(&platram_driver);
274 module_init(platram_init);
275 module_exit(platram_exit);
277 MODULE_LICENSE("GPL");
278 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
279 MODULE_DESCRIPTION("MTD platform RAM map driver");