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Diffstat (limited to 'drivers/mtd/mtdcore.c')
-rw-r--r--drivers/mtd/mtdcore.c419
1 files changed, 419 insertions, 0 deletions
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
new file mode 100644
index 00000000000..9c0315d1b1c
--- /dev/null
+++ b/drivers/mtd/mtdcore.c
@@ -0,0 +1,419 @@
+/*
+ * $Id: mtdcore.c,v 1.44 2004/11/16 18:28:59 dwmw2 Exp $
+ *
+ * Core registration and callback routines for MTD
+ * drivers and users.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/major.h>
+#include <linux/fs.h>
+#include <linux/ioctl.h>
+#include <linux/init.h>
+#include <linux/mtd/compatmac.h>
+#ifdef CONFIG_PROC_FS
+#include <linux/proc_fs.h>
+#endif
+
+#include <linux/mtd/mtd.h>
+
+/* These are exported solely for the purpose of mtd_blkdevs.c. You
+ should not use them for _anything_ else */
+DECLARE_MUTEX(mtd_table_mutex);
+struct mtd_info *mtd_table[MAX_MTD_DEVICES];
+
+EXPORT_SYMBOL_GPL(mtd_table_mutex);
+EXPORT_SYMBOL_GPL(mtd_table);
+
+static LIST_HEAD(mtd_notifiers);
+
+/**
+ * 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 the number of present devices exceeds MAX_MTD_DEVICES (i.e. 16)
+ */
+
+int add_mtd_device(struct mtd_info *mtd)
+{
+ int i;
+
+ down(&mtd_table_mutex);
+
+ for (i=0; i < MAX_MTD_DEVICES; i++)
+ if (!mtd_table[i]) {
+ struct list_head *this;
+
+ mtd_table[i] = mtd;
+ mtd->index = i;
+ mtd->usecount = 0;
+
+ DEBUG(0, "mtd: Giving out device %d to %s\n",i, mtd->name);
+ /* No need to get a refcount on the module containing
+ the notifier, since we hold the mtd_table_mutex */
+ list_for_each(this, &mtd_notifiers) {
+ struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list);
+ not->add(mtd);
+ }
+
+ up(&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. :) */
+ __module_get(THIS_MODULE);
+ return 0;
+ }
+
+ up(&mtd_table_mutex);
+ 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;
+
+ down(&mtd_table_mutex);
+
+ 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 {
+ struct list_head *this;
+
+ /* No need to get a refcount on the module containing
+ the notifier, since we hold the mtd_table_mutex */
+ list_for_each(this, &mtd_notifiers) {
+ struct mtd_notifier *not = list_entry(this, struct mtd_notifier, list);
+ not->remove(mtd);
+ }
+
+ mtd_table[mtd->index] = NULL;
+
+ module_put(THIS_MODULE);
+ ret = 0;
+ }
+
+ up(&mtd_table_mutex);
+ return ret;
+}
+
+/**
+ * register_mtd_user - register a 'user' of MTD devices.
+ * @new: pointer to notifier info structure
+ *
+ * Registers a pair of callbacks function to be called upon addition
+ * or removal of MTD devices. Causes the 'add' callback to be immediately
+ * invoked for each MTD device currently present in the system.
+ */
+
+void register_mtd_user (struct mtd_notifier *new)
+{
+ int i;
+
+ down(&mtd_table_mutex);
+
+ list_add(&new->list, &mtd_notifiers);
+
+ __module_get(THIS_MODULE);
+
+ for (i=0; i< MAX_MTD_DEVICES; i++)
+ if (mtd_table[i])
+ new->add(mtd_table[i]);
+
+ up(&mtd_table_mutex);
+}
+
+/**
+ * register_mtd_user - unregister a 'user' of MTD devices.
+ * @new: pointer to notifier info structure
+ *
+ * Removes a callback function pair from the list of 'users' to be
+ * notified upon addition or removal of MTD devices. Causes the
+ * 'remove' callback to be immediately invoked for each MTD device
+ * currently present in the system.
+ */
+
+int unregister_mtd_user (struct mtd_notifier *old)
+{
+ int i;
+
+ down(&mtd_table_mutex);
+
+ module_put(THIS_MODULE);
+
+ for (i=0; i< MAX_MTD_DEVICES; i++)
+ if (mtd_table[i])
+ old->remove(mtd_table[i]);
+
+ list_del(&old->list);
+ up(&mtd_table_mutex);
+ return 0;
+}
+
+
+/**
+ * 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 NULL
+ * if not.
+ */
+
+struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
+{
+ struct mtd_info *ret = NULL;
+ int i;
+
+ down(&mtd_table_mutex);
+
+ 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 && !try_module_get(ret->owner))
+ ret = NULL;
+
+ if (ret)
+ ret->usecount++;
+
+ up(&mtd_table_mutex);
+ return ret;
+}
+
+void put_mtd_device(struct mtd_info *mtd)
+{
+ int c;
+
+ down(&mtd_table_mutex);
+ c = --mtd->usecount;
+ up(&mtd_table_mutex);
+ BUG_ON(c < 0);
+
+ module_put(mtd->owner);
+}
+
+/* default_mtd_writev - default mtd writev method for MTD devices that
+ * dont implement their own
+ */
+
+int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
+ unsigned long count, loff_t to, size_t *retlen)
+{
+ unsigned long i;
+ size_t totlen = 0, thislen;
+ int ret = 0;
+
+ if(!mtd->write) {
+ ret = -EROFS;
+ } else {
+ for (i=0; i<count; i++) {
+ if (!vecs[i].iov_len)
+ continue;
+ ret = mtd->write(mtd, to, vecs[i].iov_len, &thislen, vecs[i].iov_base);
+ totlen += thislen;
+ if (ret || thislen != vecs[i].iov_len)
+ break;
+ to += vecs[i].iov_len;
+ }
+ }
+ if (retlen)
+ *retlen = totlen;
+ return ret;
+}
+
+
+/* default_mtd_readv - default mtd readv method for MTD devices that dont
+ * implement their own
+ */
+
+int default_mtd_readv(struct mtd_info *mtd, struct kvec *vecs,
+ unsigned long count, loff_t from, size_t *retlen)
+{
+ unsigned long i;
+ size_t totlen = 0, thislen;
+ int ret = 0;
+
+ if(!mtd->read) {
+ ret = -EIO;
+ } else {
+ for (i=0; i<count; i++) {
+ if (!vecs[i].iov_len)
+ continue;
+ ret = mtd->read(mtd, from, vecs[i].iov_len, &thislen, vecs[i].iov_base);
+ totlen += thislen;
+ if (ret || thislen != vecs[i].iov_len)
+ break;
+ from += vecs[i].iov_len;
+ }
+ }
+ if (retlen)
+ *retlen = totlen;
+ return ret;
+}
+
+
+EXPORT_SYMBOL(add_mtd_device);
+EXPORT_SYMBOL(del_mtd_device);
+EXPORT_SYMBOL(get_mtd_device);
+EXPORT_SYMBOL(put_mtd_device);
+EXPORT_SYMBOL(register_mtd_user);
+EXPORT_SYMBOL(unregister_mtd_user);
+EXPORT_SYMBOL(default_mtd_writev);
+EXPORT_SYMBOL(default_mtd_readv);
+
+/*====================================================================*/
+/* Power management code */
+
+#ifdef CONFIG_PM
+
+#include <linux/pm.h>
+
+static struct pm_dev *mtd_pm_dev = NULL;
+
+static int mtd_pm_callback(struct pm_dev *dev, pm_request_t rqst, void *data)
+{
+ int ret = 0, i;
+
+ if (down_trylock(&mtd_table_mutex))
+ return -EAGAIN;
+ if (rqst == PM_SUSPEND) {
+ for (i = 0; ret == 0 && i < MAX_MTD_DEVICES; i++) {
+ if (mtd_table[i] && mtd_table[i]->suspend)
+ ret = mtd_table[i]->suspend(mtd_table[i]);
+ }
+ } else i = MAX_MTD_DEVICES-1;
+
+ if (rqst == PM_RESUME || ret) {
+ for ( ; i >= 0; i--) {
+ if (mtd_table[i] && mtd_table[i]->resume)
+ mtd_table[i]->resume(mtd_table[i]);
+ }
+ }
+ up(&mtd_table_mutex);
+ return ret;
+}
+#endif
+
+/*====================================================================*/
+/* Support for /proc/mtd */
+
+#ifdef CONFIG_PROC_FS
+static struct proc_dir_entry *proc_mtd;
+
+static inline int mtd_proc_info (char *buf, int i)
+{
+ struct mtd_info *this = mtd_table[i];
+
+ if (!this)
+ return 0;
+
+ return sprintf(buf, "mtd%d: %8.8x %8.8x \"%s\"\n", i, this->size,
+ this->erasesize, this->name);
+}
+
+static int mtd_read_proc (char *page, char **start, off_t off, int count,
+ int *eof, void *data_unused)
+{
+ int len, l, i;
+ off_t begin = 0;
+
+ down(&mtd_table_mutex);
+
+ len = sprintf(page, "dev: size erasesize name\n");
+ for (i=0; i< MAX_MTD_DEVICES; i++) {
+
+ l = mtd_proc_info(page + len, i);
+ len += l;
+ if (len+begin > off+count)
+ goto done;
+ if (len+begin < off) {
+ begin += len;
+ len = 0;
+ }
+ }
+
+ *eof = 1;
+
+done:
+ up(&mtd_table_mutex);
+ if (off >= len+begin)
+ return 0;
+ *start = page + (off-begin);
+ return ((count < begin+len-off) ? count : begin+len-off);
+}
+
+#endif /* CONFIG_PROC_FS */
+
+/*====================================================================*/
+/* Init code */
+
+static int __init init_mtd(void)
+{
+#ifdef CONFIG_PROC_FS
+ if ((proc_mtd = create_proc_entry( "mtd", 0, NULL )))
+ proc_mtd->read_proc = mtd_read_proc;
+#endif
+
+#ifdef CONFIG_PM
+ mtd_pm_dev = pm_register(PM_UNKNOWN_DEV, 0, mtd_pm_callback);
+#endif
+ return 0;
+}
+
+static void __exit cleanup_mtd(void)
+{
+#ifdef CONFIG_PM
+ if (mtd_pm_dev) {
+ pm_unregister(mtd_pm_dev);
+ mtd_pm_dev = NULL;
+ }
+#endif
+
+#ifdef CONFIG_PROC_FS
+ if (proc_mtd)
+ remove_proc_entry( "mtd", NULL);
+#endif
+}
+
+module_init(init_mtd);
+module_exit(cleanup_mtd);
+
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("Core MTD registration and access routines");
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-25 01:26:45 +0000