diff options
Diffstat (limited to 'drivers/mtd/maps/plat-ram.c')
| -rw-r--r-- | drivers/mtd/maps/plat-ram.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/mtd/maps/plat-ram.c b/drivers/mtd/maps/plat-ram.c new file mode 100644 index 00000000000..118b04544ca --- /dev/null +++ b/drivers/mtd/maps/plat-ram.c @@ -0,0 +1,278 @@ +/* drivers/mtd/maps/plat-ram.c + * + * (c) 2004-2005 Simtec Electronics + * http://www.simtec.co.uk/products/SWLINUX/ + * Ben Dooks <ben@simtec.co.uk> + * + * Generic platfrom device based RAM map + * + * $Id: plat-ram.c,v 1.3 2005/03/19 22:41:27 gleixner Exp $ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#include <linux/module.h> +#include <linux/types.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/ioport.h> +#include <linux/device.h> + +#include <linux/mtd/mtd.h> +#include <linux/mtd/map.h> +#include <linux/mtd/partitions.h> +#include <linux/mtd/plat-ram.h> + +#include <asm/io.h> + +/* private structure for each mtd platform ram device created */ + +struct platram_info { + struct device *dev; + struct mtd_info *mtd; + struct map_info map; + struct mtd_partition *partitions; + struct resource *area; + struct platdata_mtd_ram *pdata; +}; + +/* to_platram_info() + * + * device private data to struct platram_info conversion +*/ + +static inline struct platram_info *to_platram_info(struct device *dev) +{ + return (struct platram_info *)dev_get_drvdata(dev); +} + +/* platram_setrw + * + * call the platform device's set rw/ro control + * + * to = 0 => read-only + * = 1 => read-write +*/ + +static inline void platram_setrw(struct platram_info *info, int to) +{ + if (info->pdata == NULL) + return; + + if (info->pdata->set_rw != NULL) + (info->pdata->set_rw)(info->dev, to); +} + +/* platram_remove + * + * called to remove the device from the driver's control +*/ + +static int platram_remove(struct device *dev) +{ + struct platram_info *info = to_platram_info(dev); + + dev_set_drvdata(dev, NULL); + + dev_dbg(dev, "removing device\n"); + + if (info == NULL) + return 0; + + if (info->mtd) { +#ifdef CONFIG_MTD_PARTITIONS + if (info->partitions) { + del_mtd_partitions(info->mtd); + kfree(info->partitions); + } +#endif + del_mtd_device(info->mtd); + map_destroy(info->mtd); + } + + /* ensure ram is left read-only */ + + platram_setrw(info, PLATRAM_RO); + + /* release resources */ + + if (info->area) { + release_resource(info->area); + kfree(info->area); + } + + if (info->map.virt != NULL) + iounmap(info->map.virt); + + kfree(info); + + return 0; +} + +/* platram_probe + * + * called from device drive system when a device matching our + * driver is found. +*/ + +static int platram_probe(struct device *dev) +{ + struct platform_device *pd = to_platform_device(dev); + struct platdata_mtd_ram *pdata; + struct platram_info *info; + struct resource *res; + int err = 0; + + dev_dbg(dev, "probe entered\n"); + + if (dev->platform_data == NULL) { + dev_err(dev, "no platform data supplied\n"); + err = -ENOENT; + goto exit_error; + } + + pdata = dev->platform_data; + + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (info == NULL) { + dev_err(dev, "no memory for flash info\n"); + err = -ENOMEM; + goto exit_error; + } + + memset(info, 0, sizeof(*info)); + dev_set_drvdata(dev, info); + + info->dev = dev; + info->pdata = pdata; + + /* get the resource for the memory mapping */ + + res = platform_get_resource(pd, IORESOURCE_MEM, 0); + + if (res == NULL) { + dev_err(dev, "no memory resource specified\n"); + err = -ENOENT; + goto exit_free; + } + + dev_dbg(dev, "got platform resource %p (0x%lx)\n", res, res->start); + + /* setup map parameters */ + + info->map.phys = res->start; + info->map.size = (res->end - res->start) + 1; + info->map.name = pdata->mapname != NULL ? pdata->mapname : pd->name; + info->map.bankwidth = pdata->bankwidth; + + /* register our usage of the memory area */ + + info->area = request_mem_region(res->start, info->map.size, pd->name); + if (info->area == NULL) { + dev_err(dev, "failed to request memory region\n"); + err = -EIO; + goto exit_free; + } + + /* remap the memory area */ + + info->map.virt = ioremap(res->start, info->map.size); + dev_dbg(dev, "virt %p, %lu bytes\n", info->map.virt, info->map.size); + + if (info->map.virt == NULL) { + dev_err(dev, "failed to ioremap() region\n"); + err = -EIO; + goto exit_free; + } + + simple_map_init(&info->map); + + dev_dbg(dev, "initialised map, probing for mtd\n"); + + /* probe for the right mtd map driver */ + + info->mtd = do_map_probe("map_ram" , &info->map); + if (info->mtd == NULL) { + dev_err(dev, "failed to probe for map_ram\n"); + err = -ENOMEM; + goto exit_free; + } + + info->mtd->owner = THIS_MODULE; + + platram_setrw(info, PLATRAM_RW); + + /* check to see if there are any available partitions, or wether + * to add this device whole */ + +#ifdef CONFIG_MTD_PARTITIONS + if (pdata->nr_partitions > 0) { + const char **probes = { NULL }; + + if (pdata->probes) + probes = (const char **)pdata->probes; + + err = parse_mtd_partitions(info->mtd, probes, + &info->partitions, 0); + if (err > 0) { + err = add_mtd_partitions(info->mtd, info->partitions, + err); + } + } +#endif /* CONFIG_MTD_PARTITIONS */ + + if (add_mtd_device(info->mtd)) { + dev_err(dev, "add_mtd_device() failed\n"); + err = -ENOMEM; + } + + dev_info(dev, "registered mtd device\n"); + return err; + + exit_free: + platram_remove(dev); + exit_error: + return err; +} + +/* device driver info */ + +static struct device_driver platram_driver = { + .name = "mtd-ram", + .bus = &platform_bus_type, + .probe = platram_probe, + .remove = platram_remove, +}; + +/* module init/exit */ + +static int __init platram_init(void) +{ + printk("Generic platform RAM MTD, (c) 2004 Simtec Electronics\n"); + return driver_register(&platram_driver); +} + +static void __exit platram_exit(void) +{ + driver_unregister(&platram_driver); +} + +module_init(platram_init); +module_exit(platram_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>"); +MODULE_DESCRIPTION("MTD platform RAM map driver"); |