+#define MAX_IDR_ID 64
+
+struct idr_layer {
+ int used;
+ void *ptr;
+};
+
+struct idr {
+ struct idr_layer id[MAX_IDR_ID];
+};
+
+#define DEFINE_IDR(name) struct idr name;
+
+void idr_remove(struct idr *idp, int id)
+{
+ if (idp->id[id].used)
+ idp->id[id].used = 0;
+
+ return;
+}
+void *idr_find(struct idr *idp, int id)
+{
+ if (idp->id[id].used)
+ return idp->id[id].ptr;
+
+ return NULL;
+}
+
+void *idr_get_next(struct idr *idp, int *next)
+{
+ void *ret;
+ int id = *next;
+
+ ret = idr_find(idp, id);
+ if (ret) {
+ id ++;
+ if (!idp->id[id].used)
+ id = 0;
+ *next = id;
+ } else {
+ *next = 0;
+ }
+
+ return ret;
+}
+
+int idr_alloc(struct idr *idp, void *ptr, int start, int end, gfp_t gfp_mask)
+{
+ struct idr_layer *idl;
+ int i = 0;
+
+ while (i < MAX_IDR_ID) {
+ idl = &idp->id[i];
+ if (idl->used == 0) {
+ idl->used = 1;
+ idl->ptr = ptr;
+ return i;
+ }
+ i++;
+ }
+ return -ENOSPC;
+}
+#endif
+
+static DEFINE_IDR(mtd_idr);
+
+/* These are exported solely for the purpose of mtd_blkdevs.c. You
+ should not use them for _anything_ else */
+DEFINE_MUTEX(mtd_table_mutex);
+EXPORT_SYMBOL_GPL(mtd_table_mutex);
+
+struct mtd_info *__mtd_next_device(int i)
+{
+ return idr_get_next(&mtd_idr, &i);
+}
+EXPORT_SYMBOL_GPL(__mtd_next_device);
+
+#ifndef __UBOOT__
+static LIST_HEAD(mtd_notifiers);
+
+
+#define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
+
+/* REVISIT once MTD uses the driver model better, whoever allocates
+ * the mtd_info will probably want to use the release() hook...
+ */
+static void mtd_release(struct device *dev)
+{
+ struct mtd_info __maybe_unused *mtd = dev_get_drvdata(dev);
+ dev_t index = MTD_DEVT(mtd->index);
+
+ /* remove /dev/mtdXro node if needed */
+ if (index)
+ device_destroy(&mtd_class, index + 1);
+}
+
+static int mtd_cls_suspend(struct device *dev, pm_message_t state)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return mtd ? mtd_suspend(mtd) : 0;
+}
+
+static int mtd_cls_resume(struct device *dev)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ if (mtd)
+ mtd_resume(mtd);
+ return 0;
+}
+
+static ssize_t mtd_type_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+ char *type;
+
+ switch (mtd->type) {
+ case MTD_ABSENT:
+ type = "absent";
+ break;
+ case MTD_RAM:
+ type = "ram";
+ break;
+ case MTD_ROM:
+ type = "rom";
+ break;
+ case MTD_NORFLASH:
+ type = "nor";
+ break;
+ case MTD_NANDFLASH:
+ type = "nand";
+ break;
+ case MTD_DATAFLASH:
+ type = "dataflash";
+ break;
+ case MTD_UBIVOLUME:
+ type = "ubi";
+ break;
+ case MTD_MLCNANDFLASH:
+ type = "mlc-nand";
+ break;
+ default:
+ type = "unknown";
+ }
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", type);
+}
+static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
+
+static ssize_t mtd_flags_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
+
+}
+static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
+
+static ssize_t mtd_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%llu\n",
+ (unsigned long long)mtd->size);
+
+}
+static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
+
+static ssize_t mtd_erasesize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
+
+}
+static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
+
+static ssize_t mtd_writesize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
+
+}
+static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
+
+static ssize_t mtd_subpagesize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+ unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
+
+}
+static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
+
+static ssize_t mtd_oobsize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
+
+}
+static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
+
+static ssize_t mtd_numeraseregions_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
+
+}
+static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
+ NULL);
+
+static ssize_t mtd_name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
+
+}
+static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
+
+static ssize_t mtd_ecc_strength_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
+}
+static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
+
+static ssize_t mtd_bitflip_threshold_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
+}
+
+static ssize_t mtd_bitflip_threshold_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+ unsigned int bitflip_threshold;
+ int retval;
+
+ retval = kstrtouint(buf, 0, &bitflip_threshold);
+ if (retval)
+ return retval;
+
+ mtd->bitflip_threshold = bitflip_threshold;
+ return count;
+}
+static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
+ mtd_bitflip_threshold_show,
+ mtd_bitflip_threshold_store);
+
+static ssize_t mtd_ecc_step_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct mtd_info *mtd = dev_get_drvdata(dev);
+
+ return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_step_size);
+
+}
+static DEVICE_ATTR(ecc_step_size, S_IRUGO, mtd_ecc_step_size_show, NULL);
+
+static struct attribute *mtd_attrs[] = {
+ &dev_attr_type.attr,
+ &dev_attr_flags.attr,
+ &dev_attr_size.attr,
+ &dev_attr_erasesize.attr,
+ &dev_attr_writesize.attr,
+ &dev_attr_subpagesize.attr,
+ &dev_attr_oobsize.attr,
+ &dev_attr_numeraseregions.attr,
+ &dev_attr_name.attr,
+ &dev_attr_ecc_strength.attr,
+ &dev_attr_ecc_step_size.attr,
+ &dev_attr_bitflip_threshold.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(mtd);
+
+static struct device_type mtd_devtype = {
+ .name = "mtd",
+ .groups = mtd_groups,
+ .release = mtd_release,
+};
+#endif
+
+/**
+ * add_mtd_device - register an MTD device
+ * @mtd: pointer to new MTD device info structure
+ *
+ * Add a device to the list of MTD devices present in the system, and
+ * notify each currently active MTD 'user' of its arrival. Returns
+ * zero on success or 1 on failure, which currently will only happen
+ * if there is insufficient memory or a sysfs error.
+ */
+