patch-2.4.6 linux/drivers/mtd/devices/slram.c

• Lines: 342
• Date: Tue Jun 12 10:30:27 2001
• Orig file: v2.4.5/linux/drivers/mtd/devices/slram.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.5/linux/drivers/mtd/devices/slram.c linux/drivers/mtd/devices/slram.c
@@ -0,0 +1,341 @@
+/*======================================================================
+
+  $Id: slram.c,v 1.19 2001/06/02 20:33:20 dwmw2 Exp $
+
+======================================================================*/
+
+
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/major.h>
+#include <linux/fs.h>
+#include <linux/ioctl.h>
+#include <linux/init.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/segment.h>
+#include <stdarg.h>
+
+#include <linux/mtd/mtd.h>
+
+#define SLRAM_MAX_DEVICES_PARAMS 6		/* 3 parameters / device */
+
+#define T(fmt, args...) printk(KERN_DEBUG fmt, ## args)
+#define E(fmt, args...) printk(KERN_NOTICE fmt, ## args)
+
+typedef struct slram_priv {
+	u_char *start;
+	u_char *end;
+} slram_priv_t;
+
+typedef struct slram_mtd_list {
+	struct mtd_info *mtdinfo;
+	struct slram_mtd_list *next;
+} slram_mtd_list_t;
+
+#ifdef MODULE
+static char *map[SLRAM_MAX_DEVICES_PARAMS];
+#else
+static char *map;
+#endif
+
+#ifdef MODULE
+#if LINUX_VERSION_CODE < 0x20212
+#define init_slram init_module
+#define cleanup_slram cleanup_module
+#endif
+
+MODULE_PARM(map, "3-" __MODULE_STRING(SLRAM_MAX_DEVICES_PARAMS) "s");
+MODULE_PARM_DESC(map, "List of memory regions to map. \"map=<name>, <start>, <length / end>\"");
+#endif
+
+static slram_mtd_list_t *slram_mtdlist = NULL;
+
+int slram_erase(struct mtd_info *, struct erase_info *);
+int slram_point(struct mtd_info *, loff_t, size_t, size_t *, u_char **);
+void slram_unpoint(struct mtd_info *, u_char *);
+int slram_read(struct mtd_info *, loff_t, size_t, size_t *, u_char *);
+int slram_write(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
+
+int slram_erase(struct mtd_info *mtd, struct erase_info *instr)
+{
+	slram_priv_t *priv = mtd->priv;
+
+	if (instr->addr + instr->len > mtd->size) {
+		return(-EINVAL);
+	}
+	
+	memset(priv->start + instr->addr, 0xff, instr->len);
+
+	/* This'll catch a few races. Free the thing before returning :) 
+	 * I don't feel at all ashamed. This kind of thing is possible anyway
+	 * with flash, but unlikely.
+	 */
+
+	instr->state = MTD_ERASE_DONE;
+
+	if (instr->callback) {
+		(*(instr->callback))(instr);
+	}
+	else {
+		kfree(instr);
+	}
+
+	return(0);
+}
+
+int slram_point(struct mtd_info *mtd, loff_t from, size_t len,
+		size_t *retlen, u_char **mtdbuf)
+{
+	slram_priv_t *priv = (slram_priv_t *)mtd->priv;
+
+	*mtdbuf = priv->start + from;
+	*retlen = len;
+	return(0);
+}
+
+void slram_unpoint(struct mtd_info *mtd, u_char *addr)
+{
+}
+
+int slram_read(struct mtd_info *mtd, loff_t from, size_t len,
+		size_t *retlen, u_char *buf)
+{
+	slram_priv_t *priv = (slram_priv_t *)mtd->priv;
+	
+	memcpy(buf, priv->start + from, len);
+
+	*retlen = len;
+	return(0);
+}
+
+int slram_write(struct mtd_info *mtd, loff_t to, size_t len,
+		size_t *retlen, const u_char *buf)
+{
+	slram_priv_t *priv = (slram_priv_t *)mtd->priv;
+
+	memcpy(priv->start + to, buf, len);
+
+	*retlen = len;
+	return(0);
+}
+
+/*====================================================================*/
+
+int register_device(char *name, long start, long length)
+{
+	slram_mtd_list_t **curmtd;
+
+	curmtd = &slram_mtdlist;
+	while (*curmtd) {
+		curmtd = &(*curmtd)->next;
+	}
+
+	*curmtd = kmalloc(sizeof(slram_mtd_list_t), GFP_KERNEL);
+	if (!curmtd) {
+		E("slram: Cannot allocate new MTD device.\n");
+		return(-ENOMEM);
+	}
+	(*curmtd)->mtdinfo = kmalloc(sizeof(struct mtd_info), GFP_KERNEL);
+	(*curmtd)->next = NULL;
+	
+	if ((*curmtd)->mtdinfo)	{
+		memset((char *)(*curmtd)->mtdinfo, 0, sizeof(struct mtd_info));
+		(*curmtd)->mtdinfo->priv =
+			(void *)kmalloc(sizeof(slram_priv_t), GFP_KERNEL);
+		
+		if (!(*curmtd)->mtdinfo->priv) {
+			kfree((*curmtd)->mtdinfo);
+			(*curmtd)->mtdinfo = NULL;
+		} else {
+			memset((*curmtd)->mtdinfo->priv,0,sizeof(slram_priv_t));
+		}
+	}
+
+	if (!(*curmtd)->mtdinfo) {
+		E("slram: Cannot allocate new MTD device.\n");
+		return(-ENOMEM);
+	}
+	
+	if (!(((slram_priv_t *)(*curmtd)->mtdinfo->priv)->start =
+				ioremap(start, length))) {
+		E("slram: ioremap failed\n");
+		return -EIO;
+	}
+	((slram_priv_t *)(*curmtd)->mtdinfo->priv)->end =
+		((slram_priv_t *)(*curmtd)->mtdinfo->priv)->start + length;
+
+
+	(*curmtd)->mtdinfo->name = name;
+	(*curmtd)->mtdinfo->size = length;
+	(*curmtd)->mtdinfo->flags = MTD_CLEAR_BITS | MTD_SET_BITS |
+					MTD_WRITEB_WRITEABLE | MTD_VOLATILE;
+        (*curmtd)->mtdinfo->erase = slram_erase;
+	(*curmtd)->mtdinfo->point = slram_point;
+	(*curmtd)->mtdinfo->unpoint = slram_unpoint;
+	(*curmtd)->mtdinfo->read = slram_read;
+	(*curmtd)->mtdinfo->write = slram_write;
+	(*curmtd)->mtdinfo->module = THIS_MODULE;
+	(*curmtd)->mtdinfo->type = MTD_RAM;
+	(*curmtd)->mtdinfo->erasesize = 0x10000;
+
+	if (add_mtd_device((*curmtd)->mtdinfo))	{
+		E("slram: Failed to register new device\n");
+		iounmap(((slram_priv_t *)(*curmtd)->mtdinfo->priv)->start);
+		kfree((*curmtd)->mtdinfo->priv);
+		kfree((*curmtd)->mtdinfo);
+		return(-EAGAIN);
+	}
+	T("slram: Registered device %s from %dKiB to %dKiB\n", name,
+			(int)(start / 1024), (int)((start + length) / 1024));
+	T("slram: Mapped from 0x%p to 0x%p\n",
+			((slram_priv_t *)(*curmtd)->mtdinfo->priv)->start,
+			((slram_priv_t *)(*curmtd)->mtdinfo->priv)->end);
+	return(0);	
+}
+
+void unregister_devices(void)
+{
+	slram_mtd_list_t *nextitem;
+
+	while (slram_mtdlist) {
+		nextitem = slram_mtdlist->next;
+		del_mtd_device(slram_mtdlist->mtdinfo);
+		iounmap(((slram_priv_t *)slram_mtdlist->mtdinfo->priv)->start);
+		kfree(slram_mtdlist->mtdinfo->priv);
+		kfree(slram_mtdlist->mtdinfo);
+		kfree(slram_mtdlist);
+		slram_mtdlist = nextitem;
+	}
+}
+
+int handle_unit(long value, char *unit)
+{
+	if ((*unit == 'M') || (*unit == 'm')) {
+		return(value * 1024 * 1024);
+	} else if ((*unit == 'K') || (*unit == 'k')) {
+		return(value * 1024);
+	}
+	return(value);
+}
+
+int parse_cmdline(char *devname, char *szstart, char *szlength)
+{
+	char *buffer;
+	long devstart;
+	long devlength;
+	
+	if ((!devname) || (!szstart) || (!szlength)) {
+		unregister_devices();
+		return(-EINVAL);
+	}
+
+	devstart = simple_strtoul(szstart, &buffer, 0);
+	devstart = handle_unit(devstart, buffer);
+	
+	if (*(szlength) != '+') {
+		devlength = simple_strtoul(szlength, &buffer, 0);
+		devlength = handle_unit(devlength, buffer) - devstart;
+	} else {
+		devlength = simple_strtoul(szlength + 1, &buffer, 0);
+		devlength = handle_unit(devlength, buffer);
+	}
+	T("slram: devname=%s, devstart=%li, devlength=%li\n",
+			devname, devstart, devlength);
+	if ((devstart < 0) || (devlength < 0)) {
+		E("slram: Illegal start / length parameter.\n");
+		return(-EINVAL);
+	}
+	
+	if ((devstart = register_device(devname, devstart, devlength))){
+		unregister_devices();
+		return((int)devstart);
+	}
+	return(0);
+}
+
+#ifndef MODULE
+
+static int __init mtd_slram_setup(char *str)
+{
+	map = str;
+	return(1);
+}
+
+__setup("slram=", mtd_slram_setup);
+
+#endif
+
+int init_slram(void)
+{
+	char *devname;
+	int i;
+
+#ifndef MODULE
+	char *devstart;
+	char *devlength;
+
+	i = 0;
+
+	if (!map) {
+		E("slram: not enough parameters.\n");
+		return(-EINVAL);
+	}
+	while (map) {
+		devname = devstart = devlength = NULL;
+
+		if (!(devname = strsep(&map, ","))) {
+			E("slram: No devicename specified.\n");
+			break;
+		}
+		T("slram: devname = %s\n", devname);
+		if ((!map) || (!(devstart = strsep(&map, ",")))) {
+			E("slram: No devicestart specified.\n");
+		}
+		T("slram: devstart = %s\n", devstart);
+		if ((!map) || (!(devlength = strsep(&map, ",")))) {
+			E("slram: No devicelength / -end specified.\n");
+		}
+		T("slram: devlength = %s\n", devlength);
+		if (parse_cmdline(devname, devstart, devlength) != 0) {
+			return(-EINVAL);
+		}
+	}
+#else
+	int count;
+	
+	for (count = 0; (map[count]) && (count < SLRAM_MAX_DEVICES_PARAMS);
+			count++) {
+	}
+
+	if ((count % 3 != 0) || (count == 0)) {
+		E("slram: not enough parameters.\n");
+		return(-EINVAL);
+	}
+	for (i = 0; i < (count / 3); i++) {
+		devname = map[i * 3];
+
+		if (parse_cmdline(devname, map[i * 3 + 1], map[i * 3 + 2])!=0) {
+			return(-EINVAL);
+		}
+		
+	}
+#endif /* !MODULE */
+	
+	return(0);
+}
+
+static void __exit cleanup_slram(void)
+{
+	unregister_devices();
+}
+
+module_init(init_slram);
+module_exit(cleanup_slram);