[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / firmware / dmi_scan.c

#include <linux/types.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/bootmem.h>
#include <linux/slab.h>
#include <asm/dmi.h>

static char * __init dmi_string(struct dmi_header *dm, u8 s)
{
	u8 *bp = ((u8 *) dm) + dm->length;
	char *str = "";

	if (s) {
		s--;
		while (s > 0 && *bp) {
			bp += strlen(bp) + 1;
			s--;
		}

		if (*bp != 0) {
			str = dmi_alloc(strlen(bp) + 1);
			if (str != NULL)
				strcpy(str, bp);
			else
				printk(KERN_ERR "dmi_string: out of memory.\n");
		}
	}

	return str;
}

/*
 *	We have to be cautious here. We have seen BIOSes with DMI pointers
 *	pointing to completely the wrong place for example
 */
static int __init dmi_table(u32 base, int len, int num,
			    void (*decode)(struct dmi_header *))
{
	u8 *buf, *data;
	int i = 0;

	buf = dmi_ioremap(base, len);
	if (buf == NULL)
		return -1;

	data = buf;

	/*
	 *	Stop when we see all the items the table claimed to have
	 *	OR we run off the end of the table (also happens)
	 */
	while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
		struct dmi_header *dm = (struct dmi_header *)data;
		/*
		 *  We want to know the total length (formated area and strings)
		 *  before decoding to make sure we won't run off the table in
		 *  dmi_decode or dmi_string
		 */
		data += dm->length;
		while ((data - buf < len - 1) && (data[0] || data[1]))
			data++;
		if (data - buf < len - 1)
			decode(dm);
		data += 2;
		i++;
	}
	dmi_iounmap(buf, len);
	return 0;
}

static int __init dmi_checksum(u8 *buf)
{
	u8 sum = 0;
	int a;

	for (a = 0; a < 15; a++)
		sum += buf[a];

	return sum == 0;
}

static char *dmi_ident[DMI_STRING_MAX];
static LIST_HEAD(dmi_devices);

/*
 *	Save a DMI string
 */
static void __init dmi_save_ident(struct dmi_header *dm, int slot, int string)
{
	char *p, *d = (char*) dm;

	if (dmi_ident[slot])
		return;

	p = dmi_string(dm, d[string]);
	if (p == NULL)
		return;

	dmi_ident[slot] = p;
}

static void __init dmi_save_devices(struct dmi_header *dm)
{
	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
	struct dmi_device *dev;

	for (i = 0; i < count; i++) {
		char *d = (char *)(dm + 1) + (i * 2);

		/* Skip disabled device */
		if ((*d & 0x80) == 0)
			continue;

		dev = dmi_alloc(sizeof(*dev));
		if (!dev) {
			printk(KERN_ERR "dmi_save_devices: out of memory.\n");
			break;
		}

		dev->type = *d++ & 0x7f;
		dev->name = dmi_string(dm, *d);
		dev->device_data = NULL;
		list_add(&dev->list, &dmi_devices);
	}
}

static void __init dmi_save_oem_strings_devices(struct dmi_header *dm)
{
	int i, count = *(u8 *)(dm + 1);
	struct dmi_device *dev;

	for (i = 1; i <= count; i++) {
		dev = dmi_alloc(sizeof(*dev));
		if (!dev) {
			printk(KERN_ERR
			   "dmi_save_oem_strings_devices: out of memory.\n");
			break;
		}

		dev->type = DMI_DEV_TYPE_OEM_STRING;
		dev->name = dmi_string(dm, i);
		dev->device_data = NULL;

		list_add(&dev->list, &dmi_devices);
	}
}

static void __init dmi_save_ipmi_device(struct dmi_header *dm)
{
	struct dmi_device *dev;
	void * data;

	data = dmi_alloc(dm->length);
	if (data == NULL) {
		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
		return;
	}

	memcpy(data, dm, dm->length);

	dev = dmi_alloc(sizeof(*dev));
	if (!dev) {
		printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
		return;
	}

	dev->type = DMI_DEV_TYPE_IPMI;
	dev->name = "IPMI controller";
	dev->device_data = data;

	list_add(&dev->list, &dmi_devices);
}

/*
 *	Process a DMI table entry. Right now all we care about are the BIOS
 *	and machine entries. For 2.5 we should pull the smbus controller info
 *	out of here.
 */
static void __init dmi_decode(struct dmi_header *dm)
{
	switch(dm->type) {
	case 0:		/* BIOS Information */
		dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
		dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
		dmi_save_ident(dm, DMI_BIOS_DATE, 8);
		break;
	case 1:		/* System Information */
		dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
		dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
		dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
		dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
		break;
	case 2:		/* Base Board Information */
		dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
		dmi_save_ident(dm, DMI_BOARD_NAME, 5);
		dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
		break;
	case 10:	/* Onboard Devices Information */
		dmi_save_devices(dm);
		break;
	case 11:	/* OEM Strings */
		dmi_save_oem_strings_devices(dm);
		break;
	case 38:	/* IPMI Device Information */
		dmi_save_ipmi_device(dm);
	}
}

static int __init dmi_present(char __iomem *p)
{
	u8 buf[15];
	memcpy_fromio(buf, p, 15);
	if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
		u16 num = (buf[13] << 8) | buf[12];
		u16 len = (buf[7] << 8) | buf[6];
		u32 base = (buf[11] << 24) | (buf[10] << 16) |
			(buf[9] << 8) | buf[8];

		/*
		 * DMI version 0.0 means that the real version is taken from
		 * the SMBIOS version, which we don't know at this point.
		 */
		if (buf[14] != 0)
			printk(KERN_INFO "DMI %d.%d present.\n",
			       buf[14] >> 4, buf[14] & 0xF);
		else
			printk(KERN_INFO "DMI present.\n");
		if (dmi_table(base,len, num, dmi_decode) == 0)
			return 0;
	}
	return 1;
}

void __init dmi_scan_machine(void)
{
	char __iomem *p, *q;
	int rc;

	if (efi_enabled) {
		if (efi.smbios == EFI_INVALID_TABLE_ADDR)
			goto out;

               /* This is called as a core_initcall() because it isn't
                * needed during early boot.  This also means we can
                * iounmap the space when we're done with it.
		*/
		p = dmi_ioremap(efi.smbios, 32);
		if (p == NULL)
			goto out;

		rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
		dmi_iounmap(p, 32);
		if (!rc)
			return;
	}
	else {
		/*
		 * no iounmap() for that ioremap(); it would be a no-op, but
		 * it's so early in setup that sucker gets confused into doing
		 * what it shouldn't if we actually call it.
		 */
		p = dmi_ioremap(0xF0000, 0x10000);
		if (p == NULL)
			goto out;

		for (q = p; q < p + 0x10000; q += 16) {
			rc = dmi_present(q);
			if (!rc)
				return;
		}
	}
 out:	printk(KERN_INFO "DMI not present or invalid.\n");
}

/**
 *	dmi_check_system - check system DMI data
 *	@list: array of dmi_system_id structures to match against
 *		All non-null elements of the list must match
 *		their slot's (field index's) data (i.e., each
 *		list string must be a substring of the specified
 *		DMI slot's string data) to be considered a
 *		successful match.
 *
 *	Walk the blacklist table running matching functions until someone
 *	returns non zero or we hit the end. Callback function is called for
 *	each successful match. Returns the number of matches.
 */
int dmi_check_system(struct dmi_system_id *list)
{
	int i, count = 0;
	struct dmi_system_id *d = list;

	while (d->ident) {
		for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
			int s = d->matches[i].slot;
			if (s == DMI_NONE)
				continue;
			if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
				continue;
			/* No match */
			goto fail;
		}
		count++;
		if (d->callback && d->callback(d))
			break;
fail:		d++;
	}

	return count;
}
EXPORT_SYMBOL(dmi_check_system);

/**
 *	dmi_get_system_info - return DMI data value
 *	@field: data index (see enum dmi_field)
 *
 *	Returns one DMI data value, can be used to perform
 *	complex DMI data checks.
 */
char *dmi_get_system_info(int field)
{
	return dmi_ident[field];
}
EXPORT_SYMBOL(dmi_get_system_info);

/**
 *	dmi_find_device - find onboard device by type/name
 *	@type: device type or %DMI_DEV_TYPE_ANY to match all device types
 *	@name: device name string or %NULL to match all
 *	@from: previous device found in search, or %NULL for new search.
 *
 *	Iterates through the list of known onboard devices. If a device is
 *	found with a matching @vendor and @device, a pointer to its device
 *	structure is returned.  Otherwise, %NULL is returned.
 *	A new search is initiated by passing %NULL as the @from argument.
 *	If @from is not %NULL, searches continue from next device.
 */
struct dmi_device * dmi_find_device(int type, const char *name,
				    struct dmi_device *from)
{
	struct list_head *d, *head = from ? &from->list : &dmi_devices;

	for(d = head->next; d != &dmi_devices; d = d->next) {
		struct dmi_device *dev = list_entry(d, struct dmi_device, list);

		if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
		    ((name == NULL) || (strcmp(dev->name, name) == 0)))
			return dev;
	}

	return NULL;
}
EXPORT_SYMBOL(dmi_find_device);

/**
 *	dmi_get_year - Return year of a DMI date
 *	@field:	data index (like dmi_get_system_info)
 *
 *	Returns -1 when the field doesn't exist. 0 when it is broken.
 */
int dmi_get_year(int field)
{
	int year;
	char *s = dmi_get_system_info(field);

	if (!s)
		return -1;
	if (*s == '\0')
		return 0;
	s = strrchr(s, '/');
	if (!s)
		return 0;

	s += 1;
	year = simple_strtoul(s, NULL, 0);
	if (year && year < 100) {	/* 2-digit year */
		year += 1900;
		if (year < 1996)	/* no dates < spec 1.0 */
			year += 100;
	}

	return year;
}
Commit	Line	Data
1da177e4	1	#include <linux/types.h>
1da177e4 LT	2	#include <linux/string.h>
	3	#include <linux/init.h>
	4	#include <linux/module.h>
1da177e4	5	#include <linux/dmi.h>
3ed3bce8	6	#include <linux/efi.h>
1da177e4	7	#include <linux/bootmem.h>
e9928674	8	#include <linux/slab.h>
f2d3efed	9	#include <asm/dmi.h>
1da177e4	10
1da177e4 LT	11	static char * __init dmi_string(struct dmi_header *dm, u8 s)
1da177e4 LT	12	{
1249c513	13	u8 bp = ((u8 ) dm) + dm->length;
c3c7120d	14	char *str = "";
1249c513	15
c3c7120d	16	if (s) {
1da177e4	17	s--;
c3c7120d AP	18	while (s > 0 && *bp) {
	19	bp += strlen(bp) + 1;
	20	s--;
	21	}
	22
	23	if (*bp != 0) {
e9928674	24	str = dmi_alloc(strlen(bp) + 1);
c3c7120d AP	25	if (str != NULL)
	26	strcpy(str, bp);
	27	else
	28	printk(KERN_ERR "dmi_string: out of memory.\n");
	29	}
4f705ae3	30	}
c3c7120d AP	31
c3c7120d AP	32	return str;
1da177e4 LT	33	}
	34
	35	/*
	36	* We have to be cautious here. We have seen BIOSes with DMI pointers
	37	* pointing to completely the wrong place for example
	38	*/
1249c513 AP	39	static int __init dmi_table(u32 base, int len, int num,
1249c513 AP	40	void (decode)(struct dmi_header ))
1da177e4	41	{
1249c513 AP	42	u8 buf, data;
1249c513 AP	43	int i = 0;
4f705ae3	44
e9928674	45	buf = dmi_ioremap(base, len);
1249c513	46	if (buf == NULL)
1da177e4 LT	47	return -1;
	48
	49	data = buf;
	50
	51	/*
4f705ae3 BH	52	* Stop when we see all the items the table claimed to have
	53	* OR we run off the end of the table (also happens)
	54	*/
1249c513 AP	55	while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
1249c513 AP	56	struct dmi_header dm = (struct dmi_header )data;
1da177e4 LT	57	/*
	58	* We want to know the total length (formated area and strings)
	59	* before decoding to make sure we won't run off the table in
	60	* dmi_decode or dmi_string
	61	*/
1249c513 AP	62	data += dm->length;
1249c513 AP	63	while ((data - buf < len - 1) && (data[0] \|\| data[1]))
1da177e4	64	data++;
1249c513	65	if (data - buf < len - 1)
1da177e4	66	decode(dm);
1249c513	67	data += 2;
1da177e4 LT	68	i++;
1da177e4 LT	69	}
e9928674	70	dmi_iounmap(buf, len);
1da177e4 LT	71	return 0;
	72	}
	73
1249c513	74	static int __init dmi_checksum(u8 *buf)
1da177e4	75	{
1249c513	76	u8 sum = 0;
1da177e4	77	int a;
4f705ae3	78
1249c513 AP	79	for (a = 0; a < 15; a++)
	80	sum += buf[a];
	81
	82	return sum == 0;
1da177e4 LT	83	}
1da177e4 LT	84
1da177e4	85	static char *dmi_ident[DMI_STRING_MAX];
ebad6a42	86	static LIST_HEAD(dmi_devices);
1da177e4 LT	87
	88	/*
	89	* Save a DMI string
	90	*/
1da177e4 LT	91	static void __init dmi_save_ident(struct dmi_header *dm, int slot, int string)
1da177e4 LT	92	{
c3c7120d	93	char p, d = (char*) dm;
1249c513	94
1da177e4 LT	95	if (dmi_ident[slot])
1da177e4 LT	96	return;
1249c513	97
c3c7120d AP	98	p = dmi_string(dm, d[string]);
	99	if (p == NULL)
	100	return;
	101
	102	dmi_ident[slot] = p;
1da177e4 LT	103	}
1da177e4 LT	104
ebad6a42 AP	105	static void __init dmi_save_devices(struct dmi_header *dm)
	106	{
	107	int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
	108	struct dmi_device *dev;
	109
	110	for (i = 0; i < count; i++) {
bc83455b	111	char d = (char )(dm + 1) + (i * 2);
ebad6a42 AP	112
	113	/* Skip disabled device */
	114	if ((*d & 0x80) == 0)
	115	continue;
	116
e9928674	117	dev = dmi_alloc(sizeof(*dev));
ebad6a42 AP	118	if (!dev) {
	119	printk(KERN_ERR "dmi_save_devices: out of memory.\n");
	120	break;
	121	}
	122
	123	dev->type = *d++ & 0x7f;
	124	dev->name = dmi_string(dm, *d);
	125	dev->device_data = NULL;
2e0c1f6c SM	126	list_add(&dev->list, &dmi_devices);
	127	}
	128	}
	129
	130	static void __init dmi_save_oem_strings_devices(struct dmi_header *dm)
	131	{
	132	int i, count = (u8 )(dm + 1);
	133	struct dmi_device *dev;
	134
	135	for (i = 1; i <= count; i++) {
	136	dev = dmi_alloc(sizeof(*dev));
	137	if (!dev) {
	138	printk(KERN_ERR
	139	"dmi_save_oem_strings_devices: out of memory.\n");
	140	break;
	141	}
	142
	143	dev->type = DMI_DEV_TYPE_OEM_STRING;
	144	dev->name = dmi_string(dm, i);
	145	dev->device_data = NULL;
ebad6a42 AP	146
	147	list_add(&dev->list, &dmi_devices);
	148	}
	149	}
	150
	151	static void __init dmi_save_ipmi_device(struct dmi_header *dm)
	152	{
	153	struct dmi_device *dev;
	154	void * data;
	155
e9928674	156	data = dmi_alloc(dm->length);
ebad6a42 AP	157	if (data == NULL) {
	158	printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
	159	return;
	160	}
	161
	162	memcpy(data, dm, dm->length);
	163
e9928674	164	dev = dmi_alloc(sizeof(*dev));
ebad6a42 AP	165	if (!dev) {
	166	printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
	167	return;
	168	}
	169
	170	dev->type = DMI_DEV_TYPE_IPMI;
	171	dev->name = "IPMI controller";
	172	dev->device_data = data;
	173
	174	list_add(&dev->list, &dmi_devices);
	175	}
	176
1da177e4 LT	177	/*
	178	* Process a DMI table entry. Right now all we care about are the BIOS
	179	* and machine entries. For 2.5 we should pull the smbus controller info
	180	* out of here.
	181	*/
1da177e4 LT	182	static void __init dmi_decode(struct dmi_header *dm)
1da177e4 LT	183	{
1249c513	184	switch(dm->type) {
ebad6a42	185	case 0: /* BIOS Information */
1249c513	186	dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
1249c513	187	dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
1249c513 AP	188	dmi_save_ident(dm, DMI_BIOS_DATE, 8);
1249c513 AP	189	break;
ebad6a42	190	case 1: /* System Information */
1249c513	191	dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
1249c513	192	dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
1249c513	193	dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
1249c513 AP	194	dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
1249c513 AP	195	break;
ebad6a42	196	case 2: /* Base Board Information */
1249c513	197	dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
1249c513	198	dmi_save_ident(dm, DMI_BOARD_NAME, 5);
1249c513 AP	199	dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
1249c513 AP	200	break;
ebad6a42 AP	201	case 10: /* Onboard Devices Information */
	202	dmi_save_devices(dm);
	203	break;
2e0c1f6c SM	204	case 11: /* OEM Strings */
	205	dmi_save_oem_strings_devices(dm);
	206	break;
ebad6a42 AP	207	case 38: /* IPMI Device Information */
ebad6a42 AP	208	dmi_save_ipmi_device(dm);
1da177e4 LT	209	}
	210	}
	211
3ed3bce8	212	static int __init dmi_present(char __iomem *p)
1da177e4	213	{
61e032fa	214	u8 buf[15];
3ed3bce8 MD	215	memcpy_fromio(buf, p, 15);
	216	if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
	217	u16 num = (buf[13] << 8) \| buf[12];
	218	u16 len = (buf[7] << 8) \| buf[6];
	219	u32 base = (buf[11] << 24) \| (buf[10] << 16) \|
	220	(buf[9] << 8) \| buf[8];
61e032fa	221
3ed3bce8 MD	222	/*
	223	* DMI version 0.0 means that the real version is taken from
	224	* the SMBIOS version, which we don't know at this point.
	225	*/
	226	if (buf[14] != 0)
	227	printk(KERN_INFO "DMI %d.%d present.\n",
	228	buf[14] >> 4, buf[14] & 0xF);
	229	else
	230	printk(KERN_INFO "DMI present.\n");
	231	if (dmi_table(base,len, num, dmi_decode) == 0)
	232	return 0;
	233	}
	234	return 1;
	235	}
61e032fa	236
3ed3bce8 MD	237	void __init dmi_scan_machine(void)
	238	{
	239	char __iomem p, q;
	240	int rc;
	241
	242	if (efi_enabled) {
b2c99e3c	243	if (efi.smbios == EFI_INVALID_TABLE_ADDR)
3ed3bce8 MD	244	goto out;
	245
	246	/* This is called as a core_initcall() because it isn't
	247	* needed during early boot. This also means we can
	248	* iounmap the space when we're done with it.
	249	*/
b2c99e3c	250	p = dmi_ioremap(efi.smbios, 32);
3ed3bce8 MD	251	if (p == NULL)
	252	goto out;
	253
	254	rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
23dd842c	255	dmi_iounmap(p, 32);
3ed3bce8 MD	256	if (!rc)
	257	return;
	258	}
	259	else {
	260	/*
	261	* no iounmap() for that ioremap(); it would be a no-op, but
	262	* it's so early in setup that sucker gets confused into doing
	263	* what it shouldn't if we actually call it.
	264	*/
	265	p = dmi_ioremap(0xF0000, 0x10000);
	266	if (p == NULL)
	267	goto out;
	268
	269	for (q = p; q < p + 0x10000; q += 16) {
	270	rc = dmi_present(q);
	271	if (!rc)
61e032fa AP	272	return;
	273	}
	274	}
3ed3bce8	275	out: printk(KERN_INFO "DMI not present or invalid.\n");
1da177e4 LT	276	}
1da177e4 LT	277
1da177e4 LT	278	/**
	279	* dmi_check_system - check system DMI data
	280	* @list: array of dmi_system_id structures to match against
b0ef371e RD	281	* All non-null elements of the list must match
	282	* their slot's (field index's) data (i.e., each
	283	* list string must be a substring of the specified
	284	* DMI slot's string data) to be considered a
	285	* successful match.
1da177e4 LT	286	*
	287	* Walk the blacklist table running matching functions until someone
	288	* returns non zero or we hit the end. Callback function is called for
b0ef371e	289	* each successful match. Returns the number of matches.
1da177e4 LT	290	*/
	291	int dmi_check_system(struct dmi_system_id *list)
	292	{
	293	int i, count = 0;
	294	struct dmi_system_id *d = list;
	295
	296	while (d->ident) {
	297	for (i = 0; i < ARRAY_SIZE(d->matches); i++) {
	298	int s = d->matches[i].slot;
	299	if (s == DMI_NONE)
	300	continue;
	301	if (dmi_ident[s] && strstr(dmi_ident[s], d->matches[i].substr))
	302	continue;
	303	/* No match */
	304	goto fail;
	305	}
640e8033	306	count++;
1da177e4 LT	307	if (d->callback && d->callback(d))
1da177e4 LT	308	break;
1da177e4 LT	309	fail: d++;
	310	}
	311
	312	return count;
	313	}
1da177e4 LT	314	EXPORT_SYMBOL(dmi_check_system);
	315
	316	/**
	317	* dmi_get_system_info - return DMI data value
b0ef371e	318	* @field: data index (see enum dmi_field)
1da177e4 LT	319	*
	320	* Returns one DMI data value, can be used to perform
	321	* complex DMI data checks.
	322	*/
e70c9d5e	323	char *dmi_get_system_info(int field)
1da177e4 LT	324	{
	325	return dmi_ident[field];
	326	}
e70c9d5e	327	EXPORT_SYMBOL(dmi_get_system_info);
ebad6a42 AP	328
	329	/**
	330	* dmi_find_device - find onboard device by type/name
	331	* @type: device type or %DMI_DEV_TYPE_ANY to match all device types
b0ef371e	332	* @name: device name string or %NULL to match all
ebad6a42 AP	333	* @from: previous device found in search, or %NULL for new search.
	334	*
	335	* Iterates through the list of known onboard devices. If a device is
	336	* found with a matching @vendor and @device, a pointer to its device
	337	* structure is returned. Otherwise, %NULL is returned.
b0ef371e	338	* A new search is initiated by passing %NULL as the @from argument.
ebad6a42 AP	339	* If @from is not %NULL, searches continue from next device.
	340	*/
	341	struct dmi_device * dmi_find_device(int type, const char *name,
	342	struct dmi_device *from)
	343	{
	344	struct list_head d, head = from ? &from->list : &dmi_devices;
	345
	346	for(d = head->next; d != &dmi_devices; d = d->next) {
	347	struct dmi_device *dev = list_entry(d, struct dmi_device, list);
	348
	349	if (((type == DMI_DEV_TYPE_ANY) \|\| (dev->type == type)) &&
	350	((name == NULL) \|\| (strcmp(dev->name, name) == 0)))
	351	return dev;
	352	}
	353
	354	return NULL;
	355	}
	356	EXPORT_SYMBOL(dmi_find_device);
f083a329 AK	357
	358	/**
	359	* dmi_get_year - Return year of a DMI date
	360	* @field: data index (like dmi_get_system_info)
	361	*
	362	* Returns -1 when the field doesn't exist. 0 when it is broken.
	363	*/
	364	int dmi_get_year(int field)
	365	{
	366	int year;
	367	char *s = dmi_get_system_info(field);
	368
	369	if (!s)
	370	return -1;
	371	if (*s == '\0')
	372	return 0;
	373	s = strrchr(s, '/');
	374	if (!s)
	375	return 0;
	376
	377	s += 1;
	378	year = simple_strtoul(s, NULL, 0);
	379	if (year && year < 100) { /* 2-digit year */
	380	year += 1900;
	381	if (year < 1996) /* no dates < spec 1.0 */
	382	year += 100;
	383	}
	384
	385	return year;
	386	}