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Diffstat (limited to 'drivers/mtd/chips/chipreg.c')
-rw-r--r--drivers/mtd/chips/chipreg.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/drivers/mtd/chips/chipreg.c b/drivers/mtd/chips/chipreg.c
new file mode 100644
index 000000000..a05e10368
--- /dev/null
+++ b/drivers/mtd/chips/chipreg.c
@@ -0,0 +1,102 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Registration for chip drivers
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/mtd.h>
+
+static DEFINE_SPINLOCK(chip_drvs_lock);
+static LIST_HEAD(chip_drvs_list);
+
+void register_mtd_chip_driver(struct mtd_chip_driver *drv)
+{
+ spin_lock(&chip_drvs_lock);
+ list_add(&drv->list, &chip_drvs_list);
+ spin_unlock(&chip_drvs_lock);
+}
+
+void unregister_mtd_chip_driver(struct mtd_chip_driver *drv)
+{
+ spin_lock(&chip_drvs_lock);
+ list_del(&drv->list);
+ spin_unlock(&chip_drvs_lock);
+}
+
+static struct mtd_chip_driver *get_mtd_chip_driver (const char *name)
+{
+ struct mtd_chip_driver *ret = NULL, *this;
+
+ spin_lock(&chip_drvs_lock);
+
+ list_for_each_entry(this, &chip_drvs_list, list) {
+ if (!strcmp(this->name, name)) {
+ ret = this;
+ break;
+ }
+ }
+ if (ret && !try_module_get(ret->module))
+ ret = NULL;
+
+ spin_unlock(&chip_drvs_lock);
+
+ return ret;
+}
+
+ /* Hide all the horrid details, like some silly person taking
+ get_module_symbol() away from us, from the caller. */
+
+struct mtd_info *do_map_probe(const char *name, struct map_info *map)
+{
+ struct mtd_chip_driver *drv;
+ struct mtd_info *ret;
+
+ drv = get_mtd_chip_driver(name);
+
+ if (!drv && !request_module("%s", name))
+ drv = get_mtd_chip_driver(name);
+
+ if (!drv)
+ return NULL;
+
+ ret = drv->probe(map);
+
+ /* We decrease the use count here. It may have been a
+ probe-only module, which is no longer required from this
+ point, having given us a handle on (and increased the use
+ count of) the actual driver code.
+ */
+ module_put(drv->module);
+
+ return ret;
+}
+/*
+ * Destroy an MTD device which was created for a map device.
+ * Make sure the MTD device is already unregistered before calling this
+ */
+void map_destroy(struct mtd_info *mtd)
+{
+ struct map_info *map = mtd->priv;
+
+ if (map->fldrv->destroy)
+ map->fldrv->destroy(mtd);
+
+ module_put(map->fldrv->module);
+
+ kfree(mtd);
+}
+
+EXPORT_SYMBOL(register_mtd_chip_driver);
+EXPORT_SYMBOL(unregister_mtd_chip_driver);
+EXPORT_SYMBOL(do_map_probe);
+EXPORT_SYMBOL(map_destroy);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("Core routines for registering and invoking MTD chip drivers");