diff options
Diffstat (limited to 'u-boot/drivers/mtd/mtdcore.c')
| -rw-r--r-- | u-boot/drivers/mtd/mtdcore.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/u-boot/drivers/mtd/mtdcore.c b/u-boot/drivers/mtd/mtdcore.c new file mode 100644 index 0000000..a195dda --- /dev/null +++ b/u-boot/drivers/mtd/mtdcore.c @@ -0,0 +1,188 @@ +/* + * Core registration and callback routines for MTD + * drivers and users. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/mtd/mtd.h> +#include <linux/mtd/compat.h> +#include <ubi_uboot.h> + +struct mtd_info *mtd_table[MAX_MTD_DEVICES]; + +int add_mtd_device(struct mtd_info *mtd) +{ + int i; + + BUG_ON(mtd->writesize == 0); + + for (i = 0; i < MAX_MTD_DEVICES; i++) + if (!mtd_table[i]) { + mtd_table[i] = mtd; + mtd->index = i; + mtd->usecount = 0; + + /* No need to get a refcount on the module containing + the notifier, since we hold the mtd_table_mutex */ + + /* We _know_ we aren't being removed, because + our caller is still holding us here. So none + of this try_ nonsense, and no bitching about it + either. :) */ + return 0; + } + + return 1; +} + +/** + * del_mtd_device - unregister an MTD device + * @mtd: pointer to MTD device info structure + * + * Remove a device from the list of MTD devices present in the system, + * and notify each currently active MTD 'user' of its departure. + * Returns zero on success or 1 on failure, which currently will happen + * if the requested device does not appear to be present in the list. + */ +int del_mtd_device(struct mtd_info *mtd) +{ + int ret; + + if (mtd_table[mtd->index] != mtd) { + ret = -ENODEV; + } else if (mtd->usecount) { + printk(KERN_NOTICE "Removing MTD device #%d (%s)" + " with use count %d\n", + mtd->index, mtd->name, mtd->usecount); + ret = -EBUSY; + } else { + /* No need to get a refcount on the module containing + * the notifier, since we hold the mtd_table_mutex */ + mtd_table[mtd->index] = NULL; + + ret = 0; + } + + return ret; +} + +/** + * get_mtd_device - obtain a validated handle for an MTD device + * @mtd: last known address of the required MTD device + * @num: internal device number of the required MTD device + * + * Given a number and NULL address, return the num'th entry in the device + * table, if any. Given an address and num == -1, search the device table + * for a device with that address and return if it's still present. Given + * both, return the num'th driver only if its address matches. Return + * error code if not. + */ +struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num) +{ + struct mtd_info *ret = NULL; + int i, err = -ENODEV; + + if (num == -1) { + for (i = 0; i < MAX_MTD_DEVICES; i++) + if (mtd_table[i] == mtd) + ret = mtd_table[i]; + } else if (num < MAX_MTD_DEVICES) { + ret = mtd_table[num]; + if (mtd && mtd != ret) + ret = NULL; + } + + if (!ret) + goto out_unlock; + + ret->usecount++; + return ret; + +out_unlock: + return ERR_PTR(err); +} + +/** + * get_mtd_device_nm - obtain a validated handle for an MTD device by + * device name + * @name: MTD device name to open + * + * This function returns MTD device description structure in case of + * success and an error code in case of failure. + */ +struct mtd_info *get_mtd_device_nm(const char *name) +{ + int i, err = -ENODEV; + struct mtd_info *mtd = NULL; + + for (i = 0; i < MAX_MTD_DEVICES; i++) { + if (mtd_table[i] && !strcmp(name, mtd_table[i]->name)) { + mtd = mtd_table[i]; + break; + } + } + + if (!mtd) + goto out_unlock; + + mtd->usecount++; + return mtd; + +out_unlock: + return ERR_PTR(err); +} + +void put_mtd_device(struct mtd_info *mtd) +{ + int c; + + c = --mtd->usecount; + BUG_ON(c < 0); +} + +#if defined(CONFIG_CMD_MTDPARTS_SPREAD) +/** + * mtd_get_len_incl_bad + * + * Check if length including bad blocks fits into device. + * + * @param mtd an MTD device + * @param offset offset in flash + * @param length image length + * @return image length including bad blocks in *len_incl_bad and whether or not + * the length returned was truncated in *truncated + */ +void mtd_get_len_incl_bad(struct mtd_info *mtd, uint64_t offset, + const uint64_t length, uint64_t *len_incl_bad, + int *truncated) +{ + *truncated = 0; + *len_incl_bad = 0; + + if (!mtd->block_isbad) { + *len_incl_bad = length; + return; + } + + uint64_t len_excl_bad = 0; + uint64_t block_len; + + while (len_excl_bad < length) { + if (offset >= mtd->size) { + *truncated = 1; + return; + } + + block_len = mtd->erasesize - (offset & (mtd->erasesize - 1)); + + if (!mtd->block_isbad(mtd, offset & ~(mtd->erasesize - 1))) + len_excl_bad += block_len; + + *len_incl_bad += block_len; + offset += block_len; + } +} +#endif /* defined(CONFIG_CMD_MTDPARTS_SPREAD) */ |