diff options
Diffstat (limited to 'kernel/drivers/mtd/maps/latch-addr-flash.c')
| -rw-r--r-- | kernel/drivers/mtd/maps/latch-addr-flash.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/kernel/drivers/mtd/maps/latch-addr-flash.c b/kernel/drivers/mtd/maps/latch-addr-flash.c new file mode 100644 index 000000000..cadfbe051 --- /dev/null +++ b/kernel/drivers/mtd/maps/latch-addr-flash.c @@ -0,0 +1,230 @@ +/* + * 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/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; + + 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 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; + + latch_addr_data = dev_get_platdata(&dev->dev); + + if (info->mtd != NULL) { + mtd_device_unregister(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 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_get_platdata(&dev->dev); + 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; + + mtd_device_parse_register(info->mtd, NULL, NULL, + latch_addr_data->parts, + latch_addr_data->nr_parts); + 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 = latch_addr_flash_remove, + .driver = { + .name = DRIVER_NAME, + }, +}; + +module_platform_driver(latch_addr_flash_driver); + +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"); |