android_kernel_xiaomi_sm8350/drivers/mtd/maps/uclinux.c
Mike Frysinger 33672f72b2 [MTD] [MAPS] don't force uclinux mtd map to be root dev
The cheesy uclinux mtd maps can be used for more than just the root device, so
I think we should drop the forcing.

Also, I feel like this is a policy decision that shouldnt be in the kernel in
the first place.  People who have been lazy and boot with uclinux mtd maps and
dont put root= into their commandline can simply add the appropriate root=
line either into their bootloader or into the compiled in bootargs.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
2007-05-11 11:48:15 +01:00

119 lines
2.9 KiB
C

/****************************************************************************/
/*
* uclinux.c -- generic memory mapped MTD driver for uclinux
*
* (C) Copyright 2002, Greg Ungerer (gerg@snapgear.com)
*
* $Id: uclinux.c,v 1.12 2005/11/07 11:14:29 gleixner Exp $
*/
/****************************************************************************/
#include <linux/module.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/major.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <asm/io.h>
/****************************************************************************/
struct map_info uclinux_ram_map = {
.name = "RAM",
};
struct mtd_info *uclinux_ram_mtdinfo;
/****************************************************************************/
struct mtd_partition uclinux_romfs[] = {
{ .name = "ROMfs" }
};
#define NUM_PARTITIONS ARRAY_SIZE(uclinux_romfs)
/****************************************************************************/
int uclinux_point(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char **mtdbuf)
{
struct map_info *map = mtd->priv;
*mtdbuf = (u_char *) (map->virt + ((int) from));
*retlen = len;
return(0);
}
/****************************************************************************/
int __init uclinux_mtd_init(void)
{
struct mtd_info *mtd;
struct map_info *mapp;
extern char _ebss;
unsigned long addr = (unsigned long) &_ebss;
mapp = &uclinux_ram_map;
mapp->phys = addr;
mapp->size = PAGE_ALIGN(ntohl(*((unsigned long *)(addr + 8))));
mapp->bankwidth = 4;
printk("uclinux[mtd]: RAM probe address=0x%x size=0x%x\n",
(int) mapp->phys, (int) mapp->size);
mapp->virt = ioremap_nocache(mapp->phys, mapp->size);
if (mapp->virt == 0) {
printk("uclinux[mtd]: ioremap_nocache() failed\n");
return(-EIO);
}
simple_map_init(mapp);
mtd = do_map_probe("map_ram", mapp);
if (!mtd) {
printk("uclinux[mtd]: failed to find a mapping?\n");
iounmap(mapp->virt);
return(-ENXIO);
}
mtd->owner = THIS_MODULE;
mtd->point = uclinux_point;
mtd->priv = mapp;
uclinux_ram_mtdinfo = mtd;
add_mtd_partitions(mtd, uclinux_romfs, NUM_PARTITIONS);
return(0);
}
/****************************************************************************/
void __exit uclinux_mtd_cleanup(void)
{
if (uclinux_ram_mtdinfo) {
del_mtd_partitions(uclinux_ram_mtdinfo);
map_destroy(uclinux_ram_mtdinfo);
uclinux_ram_mtdinfo = NULL;
}
if (uclinux_ram_map.virt) {
iounmap((void *) uclinux_ram_map.virt);
uclinux_ram_map.virt = 0;
}
}
/****************************************************************************/
module_init(uclinux_mtd_init);
module_exit(uclinux_mtd_cleanup);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Greg Ungerer <gerg@snapgear.com>");
MODULE_DESCRIPTION("Generic RAM based MTD for uClinux");
/****************************************************************************/