Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Simple read-only (writable only for RAM) mtdblock driver
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5)  * Copyright © 2001-2010 David Woodhouse <dwmw2@infradead.org>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/mtd/mtd.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/mtd/blktrans.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/major.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) static int mtdblock_readsect(struct mtd_blktrans_dev *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 			      unsigned long block, char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	size_t retlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	if (mtd_read(dev->mtd, (block * 512), 512, &retlen, buf))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static int mtdblock_writesect(struct mtd_blktrans_dev *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 			      unsigned long block, char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	size_t retlen;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	if (mtd_write(dev->mtd, (block * 512), 512, &retlen, buf))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		return 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) static void mtdblock_add_mtd(struct mtd_blktrans_ops *tr, struct mtd_info *mtd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	struct mtd_blktrans_dev *dev = kzalloc(sizeof(*dev), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	if (!dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 	dev->mtd = mtd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 	dev->devnum = mtd->index;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 	dev->size = mtd->size >> 9;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 	dev->tr = tr;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	dev->readonly = 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	if (add_mtd_blktrans_dev(dev))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		kfree(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) static void mtdblock_remove_dev(struct mtd_blktrans_dev *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	del_mtd_blktrans_dev(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) static struct mtd_blktrans_ops mtdblock_tr = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	.name		= "mtdblock",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 	.major		= MTD_BLOCK_MAJOR,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	.part_bits	= 0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	.blksize 	= 512,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	.readsect	= mtdblock_readsect,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	.writesect	= mtdblock_writesect,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	.add_mtd	= mtdblock_add_mtd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	.remove_dev	= mtdblock_remove_dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	.owner		= THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static int __init mtdblock_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 	return register_mtd_blktrans(&mtdblock_tr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) static void __exit mtdblock_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 	deregister_mtd_blktrans(&mtdblock_tr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) module_init(mtdblock_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) module_exit(mtdblock_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) MODULE_DESCRIPTION("Simple read-only block device emulation access to MTD devices");