OpenCloudOS-Kernel/drivers/mtd/devices/mtdram.c

236 lines
5.7 KiB
C

/*
* mtdram - a test mtd device
* $Id: mtdram.c,v 1.35 2005/01/05 18:05:12 dwmw2 Exp $
* Author: Alexander Larsson <alex@cendio.se>
*
* Copyright (c) 1999 Alexander Larsson <alex@cendio.se>
*
* This code is GPL
*
*/
#include <linux/config.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/vmalloc.h>
#include <linux/init.h>
#include <linux/mtd/compatmac.h>
#include <linux/mtd/mtd.h>
#ifndef CONFIG_MTDRAM_ABS_POS
#define CONFIG_MTDRAM_ABS_POS 0
#endif
#if CONFIG_MTDRAM_ABS_POS > 0
#include <asm/io.h>
#endif
#ifdef MODULE
static unsigned long total_size = CONFIG_MTDRAM_TOTAL_SIZE;
static unsigned long erase_size = CONFIG_MTDRAM_ERASE_SIZE;
module_param(total_size,ulong,0);
MODULE_PARM_DESC(total_size, "Total device size in KiB");
module_param(erase_size,ulong,0);
MODULE_PARM_DESC(erase_size, "Device erase block size in KiB");
#define MTDRAM_TOTAL_SIZE (total_size * 1024)
#define MTDRAM_ERASE_SIZE (erase_size * 1024)
#else
#define MTDRAM_TOTAL_SIZE (CONFIG_MTDRAM_TOTAL_SIZE * 1024)
#define MTDRAM_ERASE_SIZE (CONFIG_MTDRAM_ERASE_SIZE * 1024)
#endif
// We could store these in the mtd structure, but we only support 1 device..
static struct mtd_info *mtd_info;
static int
ram_erase(struct mtd_info *mtd, struct erase_info *instr)
{
DEBUG(MTD_DEBUG_LEVEL2, "ram_erase(pos:%ld, len:%ld)\n", (long)instr->addr, (long)instr->len);
if (instr->addr + instr->len > mtd->size) {
DEBUG(MTD_DEBUG_LEVEL1, "ram_erase() out of bounds (%ld > %ld)\n", (long)(instr->addr + instr->len), (long)mtd->size);
return -EINVAL;
}
memset((char *)mtd->priv + instr->addr, 0xff, instr->len);
instr->state = MTD_ERASE_DONE;
mtd_erase_callback(instr);
return 0;
}
static int ram_point (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char **mtdbuf)
{
if (from + len > mtd->size)
return -EINVAL;
*mtdbuf = mtd->priv + from;
*retlen = len;
return 0;
}
static void ram_unpoint (struct mtd_info *mtd, u_char *addr, loff_t from,
size_t len)
{
DEBUG(MTD_DEBUG_LEVEL2, "ram_unpoint\n");
}
static int ram_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
DEBUG(MTD_DEBUG_LEVEL2, "ram_read(pos:%ld, len:%ld)\n", (long)from, (long)len);
if (from + len > mtd->size) {
DEBUG(MTD_DEBUG_LEVEL1, "ram_read() out of bounds (%ld > %ld)\n", (long)(from + len), (long)mtd->size);
return -EINVAL;
}
memcpy(buf, mtd->priv + from, len);
*retlen=len;
return 0;
}
static int ram_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
DEBUG(MTD_DEBUG_LEVEL2, "ram_write(pos:%ld, len:%ld)\n", (long)to, (long)len);
if (to + len > mtd->size) {
DEBUG(MTD_DEBUG_LEVEL1, "ram_write() out of bounds (%ld > %ld)\n", (long)(to + len), (long)mtd->size);
return -EINVAL;
}
memcpy ((char *)mtd->priv + to, buf, len);
*retlen=len;
return 0;
}
static void __exit cleanup_mtdram(void)
{
if (mtd_info) {
del_mtd_device(mtd_info);
#if CONFIG_MTDRAM_TOTAL_SIZE > 0
if (mtd_info->priv)
#if CONFIG_MTDRAM_ABS_POS > 0
iounmap(mtd_info->priv);
#else
vfree(mtd_info->priv);
#endif
#endif
kfree(mtd_info);
}
}
int mtdram_init_device(struct mtd_info *mtd, void *mapped_address,
unsigned long size, char *name)
{
memset(mtd, 0, sizeof(*mtd));
/* Setup the MTD structure */
mtd->name = name;
mtd->type = MTD_RAM;
mtd->flags = MTD_CAP_RAM;
mtd->size = size;
mtd->erasesize = MTDRAM_ERASE_SIZE;
mtd->priv = mapped_address;
mtd->owner = THIS_MODULE;
mtd->erase = ram_erase;
mtd->point = ram_point;
mtd->unpoint = ram_unpoint;
mtd->read = ram_read;
mtd->write = ram_write;
if (add_mtd_device(mtd)) {
return -EIO;
}
return 0;
}
#if CONFIG_MTDRAM_TOTAL_SIZE > 0
#if CONFIG_MTDRAM_ABS_POS > 0
static int __init init_mtdram(void)
{
void *addr;
int err;
/* Allocate some memory */
mtd_info = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
if (!mtd_info)
return -ENOMEM;
addr = ioremap(CONFIG_MTDRAM_ABS_POS, MTDRAM_TOTAL_SIZE);
if (!addr) {
DEBUG(MTD_DEBUG_LEVEL1,
"Failed to ioremap) memory region of size %ld at ABS_POS:%ld\n",
(long)MTDRAM_TOTAL_SIZE, (long)CONFIG_MTDRAM_ABS_POS);
kfree(mtd_info);
mtd_info = NULL;
return -ENOMEM;
}
err = mtdram_init_device(mtd_info, addr,
MTDRAM_TOTAL_SIZE, "mtdram test device");
if (err)
{
iounmap(addr);
kfree(mtd_info);
mtd_info = NULL;
return err;
}
memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
return err;
}
#else /* CONFIG_MTDRAM_ABS_POS > 0 */
static int __init init_mtdram(void)
{
void *addr;
int err;
/* Allocate some memory */
mtd_info = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
if (!mtd_info)
return -ENOMEM;
addr = vmalloc(MTDRAM_TOTAL_SIZE);
if (!addr) {
DEBUG(MTD_DEBUG_LEVEL1,
"Failed to vmalloc memory region of size %ld\n",
(long)MTDRAM_TOTAL_SIZE);
kfree(mtd_info);
mtd_info = NULL;
return -ENOMEM;
}
err = mtdram_init_device(mtd_info, addr,
MTDRAM_TOTAL_SIZE, "mtdram test device");
if (err)
{
vfree(addr);
kfree(mtd_info);
mtd_info = NULL;
return err;
}
memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
return err;
}
#endif /* !(CONFIG_MTDRAM_ABS_POS > 0) */
#else /* CONFIG_MTDRAM_TOTAL_SIZE > 0 */
static int __init init_mtdram(void)
{
return 0;
}
#endif /* !(CONFIG_MTDRAM_TOTAL_SIZE > 0) */
module_init(init_mtdram);
module_exit(cleanup_mtdram);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alexander Larsson <alexl@redhat.com>");
MODULE_DESCRIPTION("Simulated MTD driver for testing");