diff --git a/drivers/net/wimax/i2400m/tx.c b/drivers/net/wimax/i2400m/tx.c
index fab27e4a4cb3..8561c0766535 100644
--- a/drivers/net/wimax/i2400m/tx.c
+++ b/drivers/net/wimax/i2400m/tx.c
@@ -258,8 +258,10 @@ enum {
 	 * Doc says maximum transaction is 16KiB. If we had 16KiB en
 	 * route and 16KiB being queued, it boils down to needing
 	 * 32KiB.
+	 * 32KiB is insufficient for 1400 MTU, hence increasing
+	 * tx buffer size to 64KiB.
 	 */
-	I2400M_TX_BUF_SIZE = 32768,
+	I2400M_TX_BUF_SIZE = 65536,
 	/**
 	 * Message header and payload descriptors have to be 16
 	 * aligned (16 + 4 * N = 16 * M). If we take that average sent
@@ -274,6 +276,19 @@ enum {
 	I2400M_TX_PLD_SIZE = sizeof(struct i2400m_msg_hdr)
 	+ I2400M_TX_PLD_MAX * sizeof(struct i2400m_pld),
 	I2400M_TX_SKIP = 0x80000000,
+	/*
+	 * 16 byte aligned MAX_MTU + 4 byte payload prefix.
+	 */
+	I2400M_MAX_MTU_ALIGN = 16,
+	I2400M_TX_PDU_SIZE = I2400M_MAX_MTU % I2400M_MAX_MTU_ALIGN
+	+ I2400M_MAX_MTU + sizeof(struct i2400m_pl_data_hdr),
+	 /*
+	  * 256 byte aligned toal size of 12 PDUs including msg header,
+	  */
+	I2400M_TX_PDU_ALIGN = 256,
+	I2400M_TX_PDU_TOTAL_SIZE = ((I2400M_TX_PDU_SIZE * I2400M_TX_PLD_MAX
+	+ sizeof(struct i2400m_msg_hdr))/I2400M_TX_PDU_ALIGN + 1)
+	* I2400M_TX_PDU_ALIGN * 2,
 };
 
 #define TAIL_FULL ((void *)~(unsigned long)NULL)
@@ -874,6 +889,8 @@ int i2400m_tx_setup(struct i2400m *i2400m)
 	INIT_WORK(&i2400m->wake_tx_ws, i2400m_wake_tx_work);
 
 	i2400m->tx_sequence = 0;
+	 /* Warn if the calculated buffer size exceeds I2400M_TX_BUF_SIZE. */
+	BUILD_BUG_ON(I2400M_TX_PDU_TOTAL_SIZE > I2400M_TX_BUF_SIZE);
 	i2400m->tx_buf = kmalloc(I2400M_TX_BUF_SIZE, GFP_KERNEL);
 	if (i2400m->tx_buf == NULL)
 		result = -ENOMEM;