--- /dev/null
+/*
+ * 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/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;
+
+ /* default value if not set by driver */
+ if (mtd->bitflip_threshold == 0)
+ mtd->bitflip_threshold = mtd->ecc_strength;
+
+
+ /* 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) */
+
+ /*
+ * Erase is an asynchronous operation. Device drivers are supposed
+ * to call instr->callback() whenever the operation completes, even
+ * if it completes with a failure.
+ * Callers are supposed to pass a callback function and wait for it
+ * to be called before writing to the block.
+ */
+int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+ if (instr->addr > mtd->size || instr->len > mtd->size - instr->addr)
+ return -EINVAL;
+ if (!(mtd->flags & MTD_WRITEABLE))
+ return -EROFS;
+ instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
+ if (!instr->len) {
+ instr->state = MTD_ERASE_DONE;
+ mtd_erase_callback(instr);
+ return 0;
+ }
+ return mtd->_erase(mtd, instr);
+}
+
+int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
+ u_char *buf)
+{
+ int ret_code;
+ if (from < 0 || from > mtd->size || len > mtd->size - from)
+ return -EINVAL;
+ if (!len)
+ return 0;
+
+ /*
+ * In the absence of an error, drivers return a non-negative integer
+ * representing the maximum number of bitflips that were corrected on
+ * any one ecc region (if applicable; zero otherwise).
+ */
+ ret_code = mtd->_read(mtd, from, len, retlen, buf);
+ if (unlikely(ret_code < 0))
+ return ret_code;
+ if (mtd->ecc_strength == 0)
+ return 0; /* device lacks ecc */
+ return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
+}
+
+int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
+ const u_char *buf)
+{
+ *retlen = 0;
+ if (to < 0 || to > mtd->size || len > mtd->size - to)
+ return -EINVAL;
+ if (!mtd->_write || !(mtd->flags & MTD_WRITEABLE))
+ return -EROFS;
+ if (!len)
+ return 0;
+ return mtd->_write(mtd, to, len, retlen, buf);
+}
+
+/*
+ * In blackbox flight recorder like scenarios we want to make successful writes
+ * in interrupt context. panic_write() is only intended to be called when its
+ * known the kernel is about to panic and we need the write to succeed. Since
+ * the kernel is not going to be running for much longer, this function can
+ * break locks and delay to ensure the write succeeds (but not sleep).
+ */
+int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
+ const u_char *buf)
+{
+ *retlen = 0;
+ if (!mtd->_panic_write)
+ return -EOPNOTSUPP;
+ if (to < 0 || to > mtd->size || len > mtd->size - to)
+ return -EINVAL;
+ if (!(mtd->flags & MTD_WRITEABLE))
+ return -EROFS;
+ if (!len)
+ return 0;
+ return mtd->_panic_write(mtd, to, len, retlen, buf);
+}
+
+int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
+{
+ ops->retlen = ops->oobretlen = 0;
+ if (!mtd->_read_oob)
+ return -EOPNOTSUPP;
+ return mtd->_read_oob(mtd, from, ops);
+}
+
+/*
+ * Method to access the protection register area, present in some flash
+ * devices. The user data is one time programmable but the factory data is read
+ * only.
+ */
+int mtd_get_fact_prot_info(struct mtd_info *mtd, struct otp_info *buf,
+ size_t len)
+{
+ if (!mtd->_get_fact_prot_info)
+ return -EOPNOTSUPP;
+ if (!len)
+ return 0;
+ return mtd->_get_fact_prot_info(mtd, buf, len);
+}
+
+int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ *retlen = 0;
+ if (!mtd->_read_fact_prot_reg)
+ return -EOPNOTSUPP;
+ if (!len)
+ return 0;
+ return mtd->_read_fact_prot_reg(mtd, from, len, retlen, buf);
+}
+
+int mtd_get_user_prot_info(struct mtd_info *mtd, struct otp_info *buf,
+ size_t len)
+{
+ if (!mtd->_get_user_prot_info)
+ return -EOPNOTSUPP;
+ if (!len)
+ return 0;
+ return mtd->_get_user_prot_info(mtd, buf, len);
+}
+
+int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ *retlen = 0;
+ if (!mtd->_read_user_prot_reg)
+ return -EOPNOTSUPP;
+ if (!len)
+ return 0;
+ return mtd->_read_user_prot_reg(mtd, from, len, retlen, buf);
+}
+
+int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ *retlen = 0;
+ if (!mtd->_write_user_prot_reg)
+ return -EOPNOTSUPP;
+ if (!len)
+ return 0;
+ return mtd->_write_user_prot_reg(mtd, to, len, retlen, buf);
+}
+
+int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
+{
+ if (!mtd->_lock_user_prot_reg)
+ return -EOPNOTSUPP;
+ if (!len)
+ return 0;
+ return mtd->_lock_user_prot_reg(mtd, from, len);
+}
+
+/* Chip-supported device locking */
+int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ if (!mtd->_lock)
+ return -EOPNOTSUPP;
+ if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
+ return -EINVAL;
+ if (!len)
+ return 0;
+ return mtd->_lock(mtd, ofs, len);
+}
+
+int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
+{
+ if (!mtd->_unlock)
+ return -EOPNOTSUPP;
+ if (ofs < 0 || ofs > mtd->size || len > mtd->size - ofs)
+ return -EINVAL;
+ if (!len)
+ return 0;
+ return mtd->_unlock(mtd, ofs, len);
+}
+
+int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
+{
+ if (!mtd->_block_isbad)
+ return 0;
+ if (ofs < 0 || ofs > mtd->size)
+ return -EINVAL;
+ return mtd->_block_isbad(mtd, ofs);
+}
+
+int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
+{
+ if (!mtd->_block_markbad)
+ return -EOPNOTSUPP;
+ if (ofs < 0 || ofs > mtd->size)
+ return -EINVAL;
+ if (!(mtd->flags & MTD_WRITEABLE))
+ return -EROFS;
+ return mtd->_block_markbad(mtd, ofs);
+}
Code Review / kvmfornfv.git / blobdiff