diff options
| author | David Howells <dhowells@redhat.com> | 2009-02-12 13:40:00 +0300 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2009-03-24 12:00:19 +0300 |
| commit | 402d326519c1a4859c527702383f4e60f606ef52 (patch) | |
| tree | beb302d56d7671d372ae73f2664feed2a5b1226d /drivers/mtd/chips | |
| parent | 9ce969082e490d0a5a81862b364337c93dc3482a (diff) | |
| download | linux-402d326519c1a4859c527702383f4e60f606ef52.tar.xz | |
NOMMU: Present backing device capabilities for MTD chardevs
Present backing device capabilities for MTD character device files to allow
NOMMU mmap to do direct mapping where possible.
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Bernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/mtd/chips')
| -rw-r--r-- | drivers/mtd/chips/map_ram.c | 17 | ||||
| -rw-r--r-- | drivers/mtd/chips/map_rom.c | 17 |
2 files changed, 34 insertions, 0 deletions
diff --git a/drivers/mtd/chips/map_ram.c b/drivers/mtd/chips/map_ram.c index 072dd8abf33a..6bdc50c727e7 100644 --- a/drivers/mtd/chips/map_ram.c +++ b/drivers/mtd/chips/map_ram.c @@ -21,6 +21,8 @@ static int mapram_write (struct mtd_info *, loff_t, size_t, size_t *, const u_ch static int mapram_erase (struct mtd_info *, struct erase_info *); static void mapram_nop (struct mtd_info *); static struct mtd_info *map_ram_probe(struct map_info *map); +static unsigned long mapram_unmapped_area(struct mtd_info *, unsigned long, + unsigned long, unsigned long); static struct mtd_chip_driver mapram_chipdrv = { @@ -64,6 +66,7 @@ static struct mtd_info *map_ram_probe(struct map_info *map) mtd->type = MTD_RAM; mtd->size = map->size; mtd->erase = mapram_erase; + mtd->get_unmapped_area = mapram_unmapped_area; mtd->read = mapram_read; mtd->write = mapram_write; mtd->sync = mapram_nop; @@ -79,6 +82,20 @@ static struct mtd_info *map_ram_probe(struct map_info *map) } +/* + * Allow NOMMU mmap() to directly map the device (if not NULL) + * - return the address to which the offset maps + * - return -ENOSYS to indicate refusal to do the mapping + */ +static unsigned long mapram_unmapped_area(struct mtd_info *mtd, + unsigned long len, + unsigned long offset, + unsigned long flags) +{ + struct map_info *map = mtd->priv; + return (unsigned long) map->virt + offset; +} + static int mapram_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) { struct map_info *map = mtd->priv; diff --git a/drivers/mtd/chips/map_rom.c b/drivers/mtd/chips/map_rom.c index c76d6e5f47ee..076090a67b90 100644 --- a/drivers/mtd/chips/map_rom.c +++ b/drivers/mtd/chips/map_rom.c @@ -20,6 +20,8 @@ static int maprom_write (struct mtd_info *, loff_t, size_t, size_t *, const u_ch static void maprom_nop (struct mtd_info *); static struct mtd_info *map_rom_probe(struct map_info *map); static int maprom_erase (struct mtd_info *mtd, struct erase_info *info); +static unsigned long maprom_unmapped_area(struct mtd_info *, unsigned long, + unsigned long, unsigned long); static struct mtd_chip_driver maprom_chipdrv = { .probe = map_rom_probe, @@ -40,6 +42,7 @@ static struct mtd_info *map_rom_probe(struct map_info *map) mtd->name = map->name; mtd->type = MTD_ROM; mtd->size = map->size; + mtd->get_unmapped_area = maprom_unmapped_area; mtd->read = maprom_read; mtd->write = maprom_write; mtd->sync = maprom_nop; @@ -53,6 +56,20 @@ static struct mtd_info *map_rom_probe(struct map_info *map) } +/* + * Allow NOMMU mmap() to directly map the device (if not NULL) + * - return the address to which the offset maps + * - return -ENOSYS to indicate refusal to do the mapping + */ +static unsigned long maprom_unmapped_area(struct mtd_info *mtd, + unsigned long len, + unsigned long offset, + unsigned long flags) +{ + struct map_info *map = mtd->priv; + return (unsigned long) map->virt + offset; +} + static int maprom_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf) { struct map_info *map = mtd->priv; |