--- a/drivers/rtc/rtc-ds1307.c	2011-10-10 11:22:22.674690998 +1300
+++ b/drivers/rtc/rtc-ds1307.c	2011-11-04 10:02:27.859155009 +1300
@@ -104,6 +104,8 @@ enum ds_type {
 
 struct ds1307 {
 	u8			offset; /* register's offset */
+	u16			nvram_offset;
+	u16			nvram_size;
 	u8			regs[11];
 	enum ds_type		type;
 	unsigned long		flags;
@@ -119,26 +121,37 @@ struct ds1307 {
 };
 
 struct chip_desc {
-	unsigned		nvram56:1;
 	unsigned		alarm:1;
+	u8			offset;
+	u16			nvram_offset;
+	u16			nvram_size;
 };
 
 static const struct chip_desc chips[last_ds_type] = {
 	[ds_1307] = {
-		.nvram56	= 1,
+		.nvram_offset	= 8,
+		.nvram_size	= 56, /* 56 bytes NVRAM */
 	},
 	[ds_1337] = {
 		.alarm		= 1,
 	},
 	[ds_1338] = {
-		.nvram56	= 1,
+		.nvram_offset	= 8,
+		.nvram_size	= 56, /* 56 bytes NVRAM */
 	},
 	[ds_1339] = {
 		.alarm		= 1,
 	},
+	[ds_1388] = {
+		.offset		= 1, /* seconds starts at 1 */
+	},
 	[ds_3231] = {
 		.alarm		= 1,
 	},
+	[mcp7941x] = {
+		.nvram_offset	= 0x20,
+		.nvram_size	= 64, /* 64 bytes SRAM */
+	},
 };
 
 static const struct i2c_device_id ds1307_id[] = {
@@ -543,8 +556,6 @@ static const struct rtc_class_ops ds13xx
 
 /*----------------------------------------------------------------------*/
 
-#define NVRAM_SIZE	56
-
 static ssize_t
 ds1307_nvram_read(struct file *filp, struct kobject *kobj,
 		struct bin_attribute *attr,
@@ -557,14 +568,15 @@ ds1307_nvram_read(struct file *filp, str
 	client = kobj_to_i2c_client(kobj);
 	ds1307 = i2c_get_clientdata(client);
 
-	if (unlikely(off >= NVRAM_SIZE))
+	if (unlikely(off >= ds1307->nvram_size))
 		return 0;
-	if ((off + count) > NVRAM_SIZE)
-		count = NVRAM_SIZE - off;
+	if ((off + count) > ds1307->nvram_size)
+		count = ds1307->nvram_size - off;
 	if (unlikely(!count))
 		return count;
 
-	result = ds1307->read_block_data(client, 8 + off, count, buf);
+	result = ds1307->read_block_data(client, ds1307->nvram_offset + off,
+								count, buf);
 	if (result < 0)
 		dev_err(&client->dev, "%s error %d\n", "nvram read", result);
 	return result;
@@ -582,14 +594,15 @@ ds1307_nvram_write(struct file *filp, st
 	client = kobj_to_i2c_client(kobj);
 	ds1307 = i2c_get_clientdata(client);
 
-	if (unlikely(off >= NVRAM_SIZE))
+	if (unlikely(off >= ds1307->nvram_size))
 		return -EFBIG;
-	if ((off + count) > NVRAM_SIZE)
-		count = NVRAM_SIZE - off;
+	if ((off + count) > ds1307->nvram_size)
+		count = ds1307->nvram_size - off;
 	if (unlikely(!count))
 		return count;
 
-	result = ds1307->write_block_data(client, 8 + off, count, buf);
+	result = ds1307->write_block_data(client, ds1307->nvram_offset + off,
+								count, buf);
 	if (result < 0) {
 		dev_err(&client->dev, "%s error %d\n", "nvram write", result);
 		return result;
@@ -605,7 +618,6 @@ static struct bin_attribute nvram = {
 
 	.read	= ds1307_nvram_read,
 	.write	= ds1307_nvram_write,
-	.size	= NVRAM_SIZE,
 };
 
 /*----------------------------------------------------------------------*/
@@ -638,7 +650,19 @@ static int __devinit ds1307_probe(struct
 
 	ds1307->client	= client;
 	ds1307->type	= id->driver_data;
-	ds1307->offset	= 0;
+
+	if (chip && chip->offset)
+		ds1307->offset = chip->offset;
+	else
+		ds1307->offset = 0;
+	if (chip && chip->nvram_size)
+		ds1307->nvram_size = chip->nvram_size;
+	else
+		ds1307->nvram_size = 0;
+	if (chip && chip->nvram_offset)
+		ds1307->nvram_offset = chip->nvram_offset;
+	else
+		ds1307->nvram_offset = 0;
 
 	buf = ds1307->regs;
 	if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) {
@@ -756,9 +780,6 @@ static int __devinit ds1307_probe(struct
 						  hour);
 		}
 		break;
-	case ds_1388:
-		ds1307->offset = 1; /* Seconds starts at 1 */
-		break;
 	default:
 		break;
 	}
@@ -893,11 +914,12 @@ read_rtc:
 		dev_dbg(&client->dev, "got IRQ %d\n", client->irq);
 	}
 
-	if (chip && chip->nvram56) {
+	if (chip && chip->nvram_size) {
+		nvram.size = ds1307->nvram_size;
 		err = sysfs_create_bin_file(&client->dev.kobj, &nvram);
 		if (err == 0) {
 			set_bit(HAS_NVRAM, &ds1307->flags);
-			dev_info(&client->dev, "56 bytes nvram\n");
+			dev_info(&client->dev, "%zd bytes nvram\n", nvram.size);
 		}
 	}