nvram.c

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	spin_unlock(&nvram_state_lock);

	return 0;
}

#ifndef CONFIG_PROC_FS
static int
nvram_read_proc(char *buffer, char **start, off_t offset,
    int size, int *eof, void *data)
{
	return 0;
}
#else

static int
nvram_read_proc(char *buffer, char **start, off_t offset,
    int size, int *eof, void *data)
{
	unsigned char contents[NVRAM_BYTES];
	int i, len = 0;
	off_t begin = 0;

	spin_lock_irq(&rtc_lock);
	for (i = 0; i < NVRAM_BYTES; ++i)
		contents[i] = __nvram_read_byte(i);
	spin_unlock_irq(&rtc_lock);

	*eof = mach_proc_infos(contents, buffer, &len, &begin, offset, size);

	if (offset >= begin + len)
		return 0;
	*start = buffer + (offset - begin);
	return (size < begin + len - offset) ? size : begin + len - offset;

}

/* This macro frees the machine specific function from bounds checking and
 * this like that... */
#define PRINT_PROC(fmt,args...)					\
	do {							\
		*len += sprintf(buffer+*len, fmt, ##args);	\
		if (*begin + *len > offset + size)		\
			return 0;				\
		if (*begin + *len < offset) {			\
			*begin += *len;				\
			*len = 0;				\
		}						\
	} while(0)

#endif /* CONFIG_PROC_FS */

static const struct file_operations nvram_fops = {
	.owner		= THIS_MODULE,
	.llseek		= nvram_llseek,
	.read		= nvram_read,
	.write		= nvram_write,
	.ioctl		= nvram_ioctl,
	.open		= nvram_open,
	.release	= nvram_release,
};

static struct miscdevice nvram_dev = {
	NVRAM_MINOR,
	"nvram",
	&nvram_fops
};

static int __init
nvram_init(void)
{
	int ret;

	/* First test whether the driver should init at all */
	if (!CHECK_DRIVER_INIT())
		return -ENXIO;

	ret = misc_register(&nvram_dev);
	if (ret) {
		printk(KERN_ERR "nvram: can't misc_register on minor=%d\n",
		    NVRAM_MINOR);
		goto out;
	}
	if (!create_proc_read_entry("driver/nvram", 0, NULL, nvram_read_proc,
		NULL)) {
		printk(KERN_ERR "nvram: can't create /proc/driver/nvram\n");
		ret = -ENOMEM;
		goto outmisc;
	}
	ret = 0;
	printk(KERN_INFO "Non-volatile memory driver v" NVRAM_VERSION "\n");
      out:
	return ret;
      outmisc:
	misc_deregister(&nvram_dev);
	goto out;
}

static void __exit
nvram_cleanup_module(void)
{
	remove_proc_entry("driver/nvram", NULL);
	misc_deregister(&nvram_dev);
}

module_init(nvram_init);
module_exit(nvram_cleanup_module);

/*
 * Machine specific functions
 */

#if MACH == PC

static int
pc_check_checksum(void)
{
	int i;
	unsigned short sum = 0;
	unsigned short expect;

	for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
		sum += __nvram_read_byte(i);
	expect = __nvram_read_byte(PC_CKS_LOC)<<8 |
	    __nvram_read_byte(PC_CKS_LOC+1);
	return ((sum & 0xffff) == expect);
}

static void
pc_set_checksum(void)
{
	int i;
	unsigned short sum = 0;

	for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
		sum += __nvram_read_byte(i);
	__nvram_write_byte(sum >> 8, PC_CKS_LOC);
	__nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1);
}

#ifdef CONFIG_PROC_FS

static char *floppy_types[] = {
	"none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M",
	"3.5'' 2.88M", "3.5'' 2.88M"
};

static char *gfx_types[] = {
	"EGA, VGA, ... (with BIOS)",
	"CGA (40 cols)",
	"CGA (80 cols)",
	"monochrome",
};

static int
pc_proc_infos(unsigned char *nvram, char *buffer, int *len,
    off_t *begin, off_t offset, int size)
{
	int checksum;
	int type;

	spin_lock_irq(&rtc_lock);
	checksum = __nvram_check_checksum();
	spin_unlock_irq(&rtc_lock);

	PRINT_PROC("Checksum status: %svalid\n", checksum ? "" : "not ");

	PRINT_PROC("# floppies     : %d\n",
	    (nvram[6] & 1) ? (nvram[6] >> 6) + 1 : 0);
	PRINT_PROC("Floppy 0 type  : ");
	type = nvram[2] >> 4;
	if (type < ARRAY_SIZE(floppy_types))
		PRINT_PROC("%s\n", floppy_types[type]);
	else
		PRINT_PROC("%d (unknown)\n", type);
	PRINT_PROC("Floppy 1 type  : ");
	type = nvram[2] & 0x0f;
	if (type < ARRAY_SIZE(floppy_types))
		PRINT_PROC("%s\n", floppy_types[type]);
	else
		PRINT_PROC("%d (unknown)\n", type);

	PRINT_PROC("HD 0 type      : ");
	type = nvram[4] >> 4;
	if (type)
		PRINT_PROC("%02x\n", type == 0x0f ? nvram[11] : type);
	else
		PRINT_PROC("none\n");

	PRINT_PROC("HD 1 type      : ");
	type = nvram[4] & 0x0f;
	if (type)
		PRINT_PROC("%02x\n", type == 0x0f ? nvram[12] : type);
	else
		PRINT_PROC("none\n");

	PRINT_PROC("HD type 48 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
	    nvram[18] | (nvram[19] << 8),
	    nvram[20], nvram[25],
	    nvram[21] | (nvram[22] << 8), nvram[23] | (nvram[24] << 8));
	PRINT_PROC("HD type 49 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
	    nvram[39] | (nvram[40] << 8),
	    nvram[41], nvram[46],
	    nvram[42] | (nvram[43] << 8), nvram[44] | (nvram[45] << 8));

	PRINT_PROC("DOS base memory: %d kB\n", nvram[7] | (nvram[8] << 8));
	PRINT_PROC("Extended memory: %d kB (configured), %d kB (tested)\n",
	    nvram[9] | (nvram[10] << 8), nvram[34] | (nvram[35] << 8));

	PRINT_PROC("Gfx adapter    : %s\n", gfx_types[(nvram[6] >> 4) & 3]);

	PRINT_PROC("FPU            : %sinstalled\n",
	    (nvram[6] & 2) ? "" : "not ");

	return 1;
}
#endif

#endif /* MACH == PC */

#if MACH == ATARI

static int
atari_check_checksum(void)
{
	int i;
	unsigned char sum = 0;

	for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
		sum += __nvram_read_byte(i);
	return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff) &&
	    __nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
}

static void
atari_set_checksum(void)
{
	int i;
	unsigned char sum = 0;

	for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
		sum += __nvram_read_byte(i);
	__nvram_write_byte(~sum, ATARI_CKS_LOC);
	__nvram_write_byte(sum, ATARI_CKS_LOC + 1);
}

#ifdef CONFIG_PROC_FS

static struct {
	unsigned char val;
	char *name;
} boot_prefs[] = {
	{ 0x80, "TOS" },
	{ 0x40, "ASV" },
	{ 0x20, "NetBSD (?)" },
	{ 0x10, "Linux" },
	{ 0x00, "unspecified" }
};

static char *languages[] = {
	"English (US)",
	"German",
	"French",
	"English (UK)",
	"Spanish",
	"Italian",
	"6 (undefined)",
	"Swiss (French)",
	"Swiss (German)"
};

static char *dateformat[] = {
	"MM%cDD%cYY",
	"DD%cMM%cYY",
	"YY%cMM%cDD",
	"YY%cDD%cMM",
	"4 (undefined)",
	"5 (undefined)",
	"6 (undefined)",
	"7 (undefined)"
};

static char *colors[] = {
	"2", "4", "16", "256", "65536", "??", "??", "??"
};

static int
atari_proc_infos(unsigned char *nvram, char *buffer, int *len,
    off_t *begin, off_t offset, int size)
{
	int checksum = nvram_check_checksum();
	int i;
	unsigned vmode;

	PRINT_PROC("Checksum status  : %svalid\n", checksum ? "" : "not ");

	PRINT_PROC("Boot preference  : ");
	for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i) {
		if (nvram[1] == boot_prefs[i].val) {
			PRINT_PROC("%s\n", boot_prefs[i].name);
			break;
		}
	}
	if (i < 0)
		PRINT_PROC("0x%02x (undefined)\n", nvram[1]);

	PRINT_PROC("SCSI arbitration : %s\n",
	    (nvram[16] & 0x80) ? "on" : "off");
	PRINT_PROC("SCSI host ID     : ");
	if (nvram[16] & 0x80)
		PRINT_PROC("%d\n", nvram[16] & 7);
	else
		PRINT_PROC("n/a\n");

	/* the following entries are defined only for the Falcon */
	if ((atari_mch_cookie >> 16) != ATARI_MCH_FALCON)
		return 1;

	PRINT_PROC("OS language      : ");
	if (nvram[6] < ARRAY_SIZE(languages))
		PRINT_PROC("%s\n", languages[nvram[6]]);
	else
		PRINT_PROC("%u (undefined)\n", nvram[6]);
	PRINT_PROC("Keyboard language: ");
	if (nvram[7] < ARRAY_SIZE(languages))
		PRINT_PROC("%s\n", languages[nvram[7]]);
	else
		PRINT_PROC("%u (undefined)\n", nvram[7]);
	PRINT_PROC("Date format      : ");
	PRINT_PROC(dateformat[nvram[8] & 7],
	    nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/');
	PRINT_PROC(", %dh clock\n", nvram[8] & 16 ? 24 : 12);
	PRINT_PROC("Boot delay       : ");
	if (nvram[10] == 0)
		PRINT_PROC("default");
	else
		PRINT_PROC("%ds%s\n", nvram[10],
		    nvram[10] < 8 ? ", no memory test" : "");

	vmode = (nvram[14] << 8) || nvram[15];
	PRINT_PROC("Video mode       : %s colors, %d columns, %s %s monitor\n",
	    colors[vmode & 7],
	    vmode & 8 ? 80 : 40,
	    vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC");
	PRINT_PROC("                   %soverscan, compat. mode %s%s\n",
	    vmode & 64 ? "" : "no ",
	    vmode & 128 ? "on" : "off",
	    vmode & 256 ?
	    (vmode & 16 ? ", line doubling" : ", half screen") : "");

	return 1;
}
#endif

#endif /* MACH == ATARI */

MODULE_LICENSE("GPL");

EXPORT_SYMBOL(__nvram_read_byte);
EXPORT_SYMBOL(nvram_read_byte);
EXPORT_SYMBOL(__nvram_write_byte);
EXPORT_SYMBOL(nvram_write_byte);
EXPORT_SYMBOL(__nvram_check_checksum);
EXPORT_SYMBOL(nvram_check_checksum);
MODULE_ALIAS_MISCDEV(NVRAM_MINOR);