--- 55edcfe5b851abe5676d1d3c857eed93c233e458
+++ 806f033695b5da1eb1e2a584bd1a950a425d3f5b
@@ -41,7 +41,8 @@
   Tolapai               0x5032     32     hard     yes     yes     yes
   ICH10                 0x3a30     32     hard     yes     yes     yes
   ICH10                 0x3a60     32     hard     yes     yes     yes
-  PCH                   0x3b30     32     hard     yes     yes     yes
+  3400/5 Series (PCH)   0x3b30     32     hard     yes     yes     yes
+  Cougar Point (PCH)    0x1c22     32     hard     yes     yes     yes
 
   Features supported by this driver:
   Software PEC                     no
@@ -415,9 +416,11 @@ static int i801_block_transaction(union
 		data->block[0] = 32;	/* max for SMBus block reads */
 	}
 
+	/* Experience has shown that the block buffer can only be used for
+	   SMBus (not I2C) block transactions, even though the datasheet
+	   doesn't mention this limitation. */
 	if ((i801_features & FEATURE_BLOCK_BUFFER)
-	 && !(command == I2C_SMBUS_I2C_BLOCK_DATA
-	      && read_write == I2C_SMBUS_READ)
+	 && command != I2C_SMBUS_I2C_BLOCK_DATA
 	 && i801_set_block_buffer_mode() == 0)
 		result = i801_block_transaction_by_block(data, read_write,
 							 hwpec);
@@ -578,6 +581,7 @@ static struct pci_device_id i801_ids[] =
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_4) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH10_5) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_PCH_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CPT_SMBUS) },
 	{ 0, }
 };
 
@@ -707,6 +711,7 @@ static int __devinit i801_probe(struct p
 	case PCI_DEVICE_ID_INTEL_ICH10_4:
 	case PCI_DEVICE_ID_INTEL_ICH10_5:
 	case PCI_DEVICE_ID_INTEL_PCH_SMBUS:
+	case PCI_DEVICE_ID_INTEL_CPT_SMBUS:
 		i801_features |= FEATURE_I2C_BLOCK_READ;
 		/* fall through */
 	case PCI_DEVICE_ID_INTEL_82801DB_3: