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/*
* mtdram - a test mtd device
* $Id: mtdram.c,v 1.25 2001/10/02 15:05:13 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/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_PARM(total_size,"l");
MODULE_PARM(erase_size,"l");
#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;
if (instr->callback)
(*(instr->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)
{
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 (mtd_info->priv)
#if CONFIG_MTDRAM_ABS_POS > 0
iounmap(mtd_info->priv);
#else
vfree(mtd_info->priv);
#endif
kfree(mtd_info);
}
}
int __init init_mtdram(void)
{
// Allocate some memory
mtd_info = (struct mtd_info *)kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
if (!mtd_info)
return 0;
memset(mtd_info, 0, sizeof(*mtd_info));
// Setup the MTD structure
mtd_info->name = "mtdram test device";
mtd_info->type = MTD_RAM;
mtd_info->flags = MTD_CAP_RAM;
mtd_info->size = MTDRAM_TOTAL_SIZE;
mtd_info->erasesize = MTDRAM_ERASE_SIZE;
#if CONFIG_MTDRAM_ABS_POS > 0
mtd_info->priv = ioremap(CONFIG_MTDRAM_ABS_POS, MTDRAM_TOTAL_SIZE);
#else
mtd_info->priv = vmalloc(MTDRAM_TOTAL_SIZE);
#endif
if (!mtd_info->priv) {
DEBUG(MTD_DEBUG_LEVEL1, "Failed to vmalloc(/ioremap) memory region of size %ld (ABS_POS:%ld)\n", (long)MTDRAM_TOTAL_SIZE, (long)CONFIG_MTDRAM_ABS_POS);
kfree(mtd_info);
mtd_info = NULL;
return -ENOMEM;
}
memset(mtd_info->priv, 0xff, MTDRAM_TOTAL_SIZE);
mtd_info->module = THIS_MODULE;
mtd_info->erase = ram_erase;
mtd_info->point = ram_point;
mtd_info->unpoint = ram_unpoint;
mtd_info->read = ram_read;
mtd_info->write = ram_write;
if (add_mtd_device(mtd_info)) {
#if CONFIG_MTDRAM_ABS_POS > 0
iounmap(mtd_info->priv);
#else
vfree(mtd_info->priv);
#endif
kfree(mtd_info);
mtd_info = NULL;
return -EIO;
}
return 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");
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