/*
* Interface for NOR flash driver whose high address lines are latched
*
* Copyright © 2000 Nicolas Pitre <nico@cam.org>
* Copyright © 2005-2008 Analog Devices Inc.
* Copyright © 2008 MontaVista Software, Inc. <source@mvista.com>
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/platform_device.h>
#include <linux/mtd/latch-addr-flash.h>
#include <linux/slab.h>
#define DRIVER_NAME "latch-addr-flash"
struct latch_addr_flash_info {
struct mtd_info *mtd;
struct map_info map;
struct resource *res;
void (*set_window)(unsigned long offset, void *data);
void *data;
/* cache; could be found out of res */
unsigned long win_mask;
int nr_parts;
struct mtd_partition *parts;
spinlock_t lock;
};
static map_word lf_read(struct map_info *map, unsigned long ofs)
{
struct latch_addr_flash_info *info;
map_word datum;
info = (struct latch_addr_flash_info *)map->map_priv_1;
spin_lock(&info->lock);
info->set_window(ofs, info->data);
datum = inline_map_read(map, info->win_mask & ofs);
spin_unlock(&info->lock);
return datum;
}
static void lf_write(struct map_info *map, map_word datum, unsigned long ofs)
{
struct latch_addr_flash_info *info;
info = (struct latch_addr_flash_info *)map->map_priv_1;
spin_lock(&info->lock);
info->set_window(ofs, info->data);
inline_map_write(map, datum, info->win_mask & ofs);
spin_unlock(&info->lock);
}
static void lf_copy_from(struct map_info *map, void *to,
unsigned long from, ssize_t len)
{
struct latch_addr_flash_info *info =
(struct latch_addr_flash_info *) map->map_priv_1;
unsigned n;
while (len > 0) {
n = info->win_mask + 1 - (from & info->win_mask);
if (n > len)
n = len;
spin_lock(&info->lock);
info->set_window(from, info->data);
memcpy_fromio(to, map->virt + (from & info->win_mask), n);
spin_unlock(&info->lock);
to += n;
from += n;
len -= n;
}
}
static char *rom_probe_types[] = { "cfi_probe", NULL };
static char *part_probe_types[] = { "cmdlinepart", NULL };
static int latch_addr_flash_remove(struct platform_device *dev)
{
struct latch_addr_flash_info *info;
struct latch_addr_flash_data *latch_addr_data;
info = platform_get_drvdata(dev);
if (info == NULL)
return 0;
platform_set_drvdata(dev, NULL);
latch_addr_data = dev->dev.platform_data;
if (info->mtd != NULL) {
if (mtd_has_partitions()) {
if (info->nr_parts) {
del_mtd_partitions(info->mtd);
kfree(info->parts);
} else if (latch_addr_data->nr_parts) {
del_mtd_partitions(info->mtd);
} else {
del_mtd_device(info->mtd);
}
} else {
del_mtd_device(info->mtd);
}
map_destroy(info->mtd);
}
if (info->map.virt != NULL)
iounmap(info->map.virt);
if (info->res != NULL)
release_mem_region(info->res->start, resource_size(info->res));
kfree(info);
if (latch_addr_data->done)
latch_addr_data->done(latch_addr_data->data);
return 0;
}
static int __devinit latch_addr_flash_probe(struct platform_device *dev)
{
struct latch_addr_flash_data *latch_addr_data;
struct latch_addr_flash_info *info;
resource_size_t win_base = dev->resource->start;
resource_size_t win_size = resource_size(dev->resource);
char **probe_type;
int chipsel;
int err;
latch_addr_data = dev->dev.platform_data;
if (latch_addr_data == NULL)
return -ENODEV;
pr_notice("latch-addr platform flash device: %#llx byte "
"window at %#.8llx\n",
(unsigned long long)win_size, (unsigned long long)win_base);
chipsel = dev->id;
if (latch_addr_data->init) {
err = latch_addr_data->init(latch_addr_data->data, chipsel);
if (err != 0)
return err;
}
info = kzalloc(sizeof(struct latch_addr_flash_info), GFP_KERNEL);
if (info == NULL) {
err = -ENOMEM;
goto done;
}
platform_set_drvdata(dev, info);
info->res = request_mem_region(win_base, win_size, DRIVER_NAME);
if (info->res == NULL) {
dev_err(&dev->dev, "Could not reserve memory region\n");
err = -EBUSY;
goto free_info;
}
info->map.name = DRIVER_NAME;
info->map.size = latch_addr_data->size;
info->map.bankwidth = latch_addr_data->width;
info->map.phys = NO_XIP;
info->map.virt = ioremap(win_base, win_size);
if (!info->map.virt) {
err = -ENOMEM;
goto free_res;
}
info->map.map_priv_1 = (unsigned long)info;
info->map.read = lf_read;
info->map.copy_from = lf_copy_from;
info->map.write = lf_write;
info->set_window = latch_addr_data->set_window;
info->data = latch_addr_data->data;
info->win_mask = win_size - 1;
spin_lock_init(&info->lock);
for (probe_type = rom_probe_types; !info->mtd && *probe_type;
probe_type++)
info->mtd = do_map_probe(*probe_type, &info->map);
if (info->mtd == NULL) {
dev_err(&dev->dev, "map_probe failed\n");
err = -ENODEV;
goto iounmap;
}
info->mtd->owner = THIS_MODULE;
if (mtd_has_partitions()) {
err = parse_mtd_partitions(info->mtd,
(const char **)part_probe_types,
&info->parts, 0);
if (err > 0) {
add_mtd_partitions(info->mtd, info->parts, err);
return 0;
}
if (latch_addr_data->nr_parts) {
pr_notice("Using latch-addr-flash partition information\n");
add_mtd_partitions(info->mtd, latch_addr_data->parts,
latch_addr_data->nr_parts);
return 0;
}
}
add_mtd_device(info->mtd);
return 0;
iounmap:
iounmap(info->map.virt);
free_res:
release_mem_region(info->res->start, resource_size(info->res));
free_info:
kfree(info);
done:
if (latch_addr_data->done)
latch_addr_data->done(latch_addr_data->data);
return err;
}
static struct platform_driver latch_addr_flash_driver = {
.probe = latch_addr_flash_probe,
.remove = __devexit_p(latch_addr_flash_remove),
.driver = {
.name = DRIVER_NAME,
},
};
static int __init latch_addr_flash_init(void)
{
return platform_driver_register(&latch_addr_flash_driver);
}
module_init(latch_addr_flash_init);
static void __exit latch_addr_flash_exit(void)
{
platform_driver_unregister(&latch_addr_flash_driver);
}
module_exit(latch_addr_flash_exit);
MODULE_AUTHOR("David Griego <dgriego@mvista.com>");
MODULE_DESCRIPTION("MTD map driver for flashes addressed physically with upper "
"address lines being set board specifically");
MODULE_LICENSE("GPL v2");
