Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 into for-davem

1 files changed, 660 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlegacy/iwl-tx.c b/drivers/net/wireless/iwlegacy/iwl-tx.c
new file mode 100644
index 00000000000..a227773cb38
--- /dev/null
+++ b/drivers/net/wireless/iwlegacy/iwl-tx.c
@@ -0,0 +1,660 @@
+/******************************************************************************
+ *
+ * Copyright(c) 2003 - 2011 Intel Corporation. All rights reserved.
+ *
+ * Portions of this file are derived from the ipw3945 project, as well
+ * as portions of the ieee80211 subsystem header files.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called LICENSE.
+ *
+ * Contact Information:
+ *  Intel Linux Wireless <ilw@linux.intel.com>
+ * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
+ *
+ *****************************************************************************/
+
+#include <linux/etherdevice.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <net/mac80211.h>
+#include "iwl-eeprom.h"
+#include "iwl-dev.h"
+#include "iwl-core.h"
+#include "iwl-sta.h"
+#include "iwl-io.h"
+#include "iwl-helpers.h"
+
+/**
+ * iwl_legacy_txq_update_write_ptr - Send new write index to hardware
+ */
+void
+iwl_legacy_txq_update_write_ptr(struct iwl_priv *priv, struct iwl_tx_queue *txq)
+{
+	u32 reg = 0;
+	int txq_id = txq->q.id;
+
+	if (txq->need_update == 0)
+		return;
+
+	/* if we're trying to save power */
+	if (test_bit(STATUS_POWER_PMI, &priv->status)) {
+		/* wake up nic if it's powered down ...
+		 * uCode will wake up, and interrupt us again, so next
+		 * time we'll skip this part. */
+		reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
+
+		if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
+			IWL_DEBUG_INFO(priv,
+					"Tx queue %d requesting wakeup,"
+					" GP1 = 0x%x\n", txq_id, reg);
+			iwl_legacy_set_bit(priv, CSR_GP_CNTRL,
+					CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
+			return;
+		}
+
+		iwl_legacy_write_direct32(priv, HBUS_TARG_WRPTR,
+				txq->q.write_ptr | (txq_id << 8));
+
+		/*
+		 * else not in power-save mode,
+		 * uCode will never sleep when we're
+		 * trying to tx (during RFKILL, we're not trying to tx).
+		 */
+	} else
+		iwl_write32(priv, HBUS_TARG_WRPTR,
+			    txq->q.write_ptr | (txq_id << 8));
+	txq->need_update = 0;
+}
+EXPORT_SYMBOL(iwl_legacy_txq_update_write_ptr);
+
+/**
+ * iwl_legacy_tx_queue_unmap -  Unmap any remaining DMA mappings and free skb's
+ */
+void iwl_legacy_tx_queue_unmap(struct iwl_priv *priv, int txq_id)
+{
+	struct iwl_tx_queue *txq = &priv->txq[txq_id];
+	struct iwl_queue *q = &txq->q;
+
+	if (q->n_bd == 0)
+		return;
+
+	while (q->write_ptr != q->read_ptr) {
+		priv->cfg->ops->lib->txq_free_tfd(priv, txq);
+		q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd);
+	}
+}
+EXPORT_SYMBOL(iwl_legacy_tx_queue_unmap);
+
+/**
+ * iwl_legacy_tx_queue_free - Deallocate DMA queue.
+ * @txq: Transmit queue to deallocate.
+ *
+ * Empty queue by removing and destroying all BD's.
+ * Free all buffers.
+ * 0-fill, but do not free "txq" descriptor structure.
+ */
+void iwl_legacy_tx_queue_free(struct iwl_priv *priv, int txq_id)
+{
+	struct iwl_tx_queue *txq = &priv->txq[txq_id];
+	struct device *dev = &priv->pci_dev->dev;
+	int i;
+
+	iwl_legacy_tx_queue_unmap(priv, txq_id);
+
+	/* De-alloc array of command/tx buffers */
+	for (i = 0; i < TFD_TX_CMD_SLOTS; i++)
+		kfree(txq->cmd[i]);
+
+	/* De-alloc circular buffer of TFDs */
+	if (txq->q.n_bd)
+		dma_free_coherent(dev, priv->hw_params.tfd_size *
+				  txq->q.n_bd, txq->tfds, txq->q.dma_addr);
+
+	/* De-alloc array of per-TFD driver data */
+	kfree(txq->txb);
+	txq->txb = NULL;
+
+	/* deallocate arrays */
+	kfree(txq->cmd);
+	kfree(txq->meta);
+	txq->cmd = NULL;
+	txq->meta = NULL;
+
+	/* 0-fill queue descriptor structure */
+	memset(txq, 0, sizeof(*txq));
+}
+EXPORT_SYMBOL(iwl_legacy_tx_queue_free);
+
+/**
+ * iwl_cmd_queue_unmap - Unmap any remaining DMA mappings from command queue
+ */
+void iwl_legacy_cmd_queue_unmap(struct iwl_priv *priv)
+{
+	struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
+	struct iwl_queue *q = &txq->q;
+	bool huge = false;
+	int i;
+
+	if (q->n_bd == 0)
+		return;
+
+	while (q->read_ptr != q->write_ptr) {
+		/* we have no way to tell if it is a huge cmd ATM */
+		i = iwl_legacy_get_cmd_index(q, q->read_ptr, 0);
+
+		if (txq->meta[i].flags & CMD_SIZE_HUGE)
+			huge = true;
+		else
+			pci_unmap_single(priv->pci_dev,
+					 dma_unmap_addr(&txq->meta[i], mapping),
+					 dma_unmap_len(&txq->meta[i], len),
+					 PCI_DMA_BIDIRECTIONAL);
+
+		q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd);
+	}
+
+	if (huge) {
+		i = q->n_window;
+		pci_unmap_single(priv->pci_dev,
+				 dma_unmap_addr(&txq->meta[i], mapping),
+				 dma_unmap_len(&txq->meta[i], len),
+				 PCI_DMA_BIDIRECTIONAL);
+	}
+}
+EXPORT_SYMBOL(iwl_legacy_cmd_queue_unmap);
+
+/**
+ * iwl_legacy_cmd_queue_free - Deallocate DMA queue.
+ * @txq: Transmit queue to deallocate.
+ *
+ * Empty queue by removing and destroying all BD's.
+ * Free all buffers.
+ * 0-fill, but do not free "txq" descriptor structure.
+ */
+void iwl_legacy_cmd_queue_free(struct iwl_priv *priv)
+{
+	struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
+	struct device *dev = &priv->pci_dev->dev;
+	int i;
+
+	iwl_legacy_cmd_queue_unmap(priv);
+
+	/* De-alloc array of command/tx buffers */
+	for (i = 0; i <= TFD_CMD_SLOTS; i++)
+		kfree(txq->cmd[i]);
+
+	/* De-alloc circular buffer of TFDs */
+	if (txq->q.n_bd)
+		dma_free_coherent(dev, priv->hw_params.tfd_size * txq->q.n_bd,
+				  txq->tfds, txq->q.dma_addr);
+
+	/* deallocate arrays */
+	kfree(txq->cmd);
+	kfree(txq->meta);
+	txq->cmd = NULL;
+	txq->meta = NULL;
+
+	/* 0-fill queue descriptor structure */
+	memset(txq, 0, sizeof(*txq));
+}
+EXPORT_SYMBOL(iwl_legacy_cmd_queue_free);
+
+/*************** DMA-QUEUE-GENERAL-FUNCTIONS  *****
+ * DMA services
+ *
+ * Theory of operation
+ *
+ * A Tx or Rx queue resides in host DRAM, and is comprised of a circular buffer
+ * of buffer descriptors, each of which points to one or more data buffers for
+ * the device to read from or fill.  Driver and device exchange status of each
+ * queue via "read" and "write" pointers.  Driver keeps minimum of 2 empty
+ * entries in each circular buffer, to protect against confusing empty and full
+ * queue states.
+ *
+ * The device reads or writes the data in the queues via the device's several
+ * DMA/FIFO channels.  Each queue is mapped to a single DMA channel.
+ *
+ * For Tx queue, there are low mark and high mark limits. If, after queuing
+ * the packet for Tx, free space become < low mark, Tx queue stopped. When
+ * reclaiming packets (on 'tx done IRQ), if free space become > high mark,
+ * Tx queue resumed.
+ *
+ * See more detailed info in iwl-4965-hw.h.
+ ***************************************************/
+
+int iwl_legacy_queue_space(const struct iwl_queue *q)
+{
+	int s = q->read_ptr - q->write_ptr;
+
+	if (q->read_ptr > q->write_ptr)
+		s -= q->n_bd;
+
+	if (s <= 0)
+		s += q->n_window;
+	/* keep some reserve to not confuse empty and full situations */
+	s -= 2;
+	if (s < 0)
+		s = 0;
+	return s;
+}
+EXPORT_SYMBOL(iwl_legacy_queue_space);
+
+
+/**
+ * iwl_legacy_queue_init - Initialize queue's high/low-water and read/write indexes
+ */
+static int iwl_legacy_queue_init(struct iwl_priv *priv, struct iwl_queue *q,
+			  int count, int slots_num, u32 id)
+{
+	q->n_bd = count;
+	q->n_window = slots_num;
+	q->id = id;
+
+	/* count must be power-of-two size, otherwise iwl_legacy_queue_inc_wrap
+	 * and iwl_legacy_queue_dec_wrap are broken. */
+	BUG_ON(!is_power_of_2(count));
+
+	/* slots_num must be power-of-two size, otherwise
+	 * iwl_legacy_get_cmd_index is broken. */
+	BUG_ON(!is_power_of_2(slots_num));
+
+	q->low_mark = q->n_window / 4;
+	if (q->low_mark < 4)
+		q->low_mark = 4;
+
+	q->high_mark = q->n_window / 8;
+	if (q->high_mark < 2)
+		q->high_mark = 2;
+
+	q->write_ptr = q->read_ptr = 0;
+
+	return 0;
+}
+
+/**
+ * iwl_legacy_tx_queue_alloc - Alloc driver data and TFD CB for one Tx/cmd queue
+ */
+static int iwl_legacy_tx_queue_alloc(struct iwl_priv *priv,
+			      struct iwl_tx_queue *txq, u32 id)
+{
+	struct device *dev = &priv->pci_dev->dev;
+	size_t tfd_sz = priv->hw_params.tfd_size * TFD_QUEUE_SIZE_MAX;
+
+	/* Driver private data, only for Tx (not command) queues,
+	 * not shared with device. */
+	if (id != priv->cmd_queue) {
+		txq->txb = kzalloc(sizeof(txq->txb[0]) *
+				   TFD_QUEUE_SIZE_MAX, GFP_KERNEL);
+		if (!txq->txb) {
+			IWL_ERR(priv, "kmalloc for auxiliary BD "
+				  "structures failed\n");
+			goto error;
+		}
+	} else {
+		txq->txb = NULL;
+	}
+
+	/* Circular buffer of transmit frame descriptors (TFDs),
+	 * shared with device */
+	txq->tfds = dma_alloc_coherent(dev, tfd_sz, &txq->q.dma_addr,
+				       GFP_KERNEL);
+	if (!txq->tfds) {
+		IWL_ERR(priv, "pci_alloc_consistent(%zd) failed\n", tfd_sz);
+		goto error;
+	}
+	txq->q.id = id;
+
+	return 0;
+
+ error:
+	kfree(txq->txb);
+	txq->txb = NULL;
+
+	return -ENOMEM;
+}
+
+/**
+ * iwl_legacy_tx_queue_init - Allocate and initialize one tx/cmd queue
+ */
+int iwl_legacy_tx_queue_init(struct iwl_priv *priv, struct iwl_tx_queue *txq,
+		      int slots_num, u32 txq_id)
+{
+	int i, len;
+	int ret;
+	int actual_slots = slots_num;
+
+	/*
+	 * Alloc buffer array for commands (Tx or other types of commands).
+	 * For the command queue (#4/#9), allocate command space + one big
+	 * command for scan, since scan command is very huge; the system will
+	 * not have two scans at the same time, so only one is needed.
+	 * For normal Tx queues (all other queues), no super-size command
+	 * space is needed.
+	 */
+	if (txq_id == priv->cmd_queue)
+		actual_slots++;
+
+	txq->meta = kzalloc(sizeof(struct iwl_cmd_meta) * actual_slots,
+			    GFP_KERNEL);
+	txq->cmd = kzalloc(sizeof(struct iwl_device_cmd *) * actual_slots,
+			   GFP_KERNEL);
+
+	if (!txq->meta || !txq->cmd)
+		goto out_free_arrays;
+
+	len = sizeof(struct iwl_device_cmd);
+	for (i = 0; i < actual_slots; i++) {
+		/* only happens for cmd queue */
+		if (i == slots_num)
+			len = IWL_MAX_CMD_SIZE;
+
+		txq->cmd[i] = kmalloc(len, GFP_KERNEL);
+		if (!txq->cmd[i])
+			goto err;
+	}
+
+	/* Alloc driver data array and TFD circular buffer */
+	ret = iwl_legacy_tx_queue_alloc(priv, txq, txq_id);
+	if (ret)
+		goto err;
+
+	txq->need_update = 0;
+
+	/*
+	 * For the default queues 0-3, set up the swq_id
+	 * already -- all others need to get one later
+	 * (if they need one at all).
+	 */
+	if (txq_id < 4)
+		iwl_legacy_set_swq_id(txq, txq_id, txq_id);
+
+	/* TFD_QUEUE_SIZE_MAX must be power-of-two size, otherwise
+	 * iwl_legacy_queue_inc_wrap and iwl_legacy_queue_dec_wrap are broken. */
+	BUILD_BUG_ON(TFD_QUEUE_SIZE_MAX & (TFD_QUEUE_SIZE_MAX - 1));
+
+	/* Initialize queue's high/low-water marks, and head/tail indexes */
+	iwl_legacy_queue_init(priv, &txq->q,
+				TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
+
+	/* Tell device where to find queue */
+	priv->cfg->ops->lib->txq_init(priv, txq);
+
+	return 0;
+err:
+	for (i = 0; i < actual_slots; i++)
+		kfree(txq->cmd[i]);
+out_free_arrays:
+	kfree(txq->meta);
+	kfree(txq->cmd);
+
+	return -ENOMEM;
+}
+EXPORT_SYMBOL(iwl_legacy_tx_queue_init);
+
+void iwl_legacy_tx_queue_reset(struct iwl_priv *priv, struct iwl_tx_queue *txq,
+			int slots_num, u32 txq_id)
+{
+	int actual_slots = slots_num;
+
+	if (txq_id == priv->cmd_queue)
+		actual_slots++;
+
+	memset(txq->meta, 0, sizeof(struct iwl_cmd_meta) * actual_slots);
+
+	txq->need_update = 0;
+
+	/* Initialize queue's high/low-water marks, and head/tail indexes */
+	iwl_legacy_queue_init(priv, &txq->q,
+				TFD_QUEUE_SIZE_MAX, slots_num, txq_id);
+
+	/* Tell device where to find queue */
+	priv->cfg->ops->lib->txq_init(priv, txq);
+}
+EXPORT_SYMBOL(iwl_legacy_tx_queue_reset);
+
+/*************** HOST COMMAND QUEUE FUNCTIONS   *****/
+
+/**
+ * iwl_legacy_enqueue_hcmd - enqueue a uCode command
+ * @priv: device private data point
+ * @cmd: a point to the ucode command structure
+ *
+ * The function returns < 0 values to indicate the operation is
+ * failed. On success, it turns the index (> 0) of command in the
+ * command queue.
+ */
+int iwl_legacy_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
+{
+	struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
+	struct iwl_queue *q = &txq->q;
+	struct iwl_device_cmd *out_cmd;
+	struct iwl_cmd_meta *out_meta;
+	dma_addr_t phys_addr;
+	unsigned long flags;
+	int len;
+	u32 idx;
+	u16 fix_size;
+
+	cmd->len = priv->cfg->ops->utils->get_hcmd_size(cmd->id, cmd->len);
+	fix_size = (u16)(cmd->len + sizeof(out_cmd->hdr));
+
+	/* If any of the command structures end up being larger than
+	 * the TFD_MAX_PAYLOAD_SIZE, and it sent as a 'small' command then
+	 * we will need to increase the size of the TFD entries
+	 * Also, check to see if command buffer should not exceed the size
+	 * of device_cmd and max_cmd_size. */
+	BUG_ON((fix_size > TFD_MAX_PAYLOAD_SIZE) &&
+	       !(cmd->flags & CMD_SIZE_HUGE));
+	BUG_ON(fix_size > IWL_MAX_CMD_SIZE);
+
+	if (iwl_legacy_is_rfkill(priv) || iwl_legacy_is_ctkill(priv)) {
+		IWL_WARN(priv, "Not sending command - %s KILL\n",
+			 iwl_legacy_is_rfkill(priv) ? "RF" : "CT");
+		return -EIO;
+	}
+
+	if (iwl_legacy_queue_space(q) < ((cmd->flags & CMD_ASYNC) ? 2 : 1)) {
+		IWL_ERR(priv, "No space in command queue\n");
+		IWL_ERR(priv, "Restarting adapter due to queue full\n");
+		queue_work(priv->workqueue, &priv->restart);
+		return -ENOSPC;
+	}
+
+	spin_lock_irqsave(&priv->hcmd_lock, flags);
+
+	/* If this is a huge cmd, mark the huge flag also on the meta.flags
+	 * of the _original_ cmd. This is used for DMA mapping clean up.
+	 */
+	if (cmd->flags & CMD_SIZE_HUGE) {
+		idx = iwl_legacy_get_cmd_index(q, q->write_ptr, 0);
+		txq->meta[idx].flags = CMD_SIZE_HUGE;
+	}
+
+	idx = iwl_legacy_get_cmd_index(q, q->write_ptr, cmd->flags & CMD_SIZE_HUGE);
+	out_cmd = txq->cmd[idx];
+	out_meta = &txq->meta[idx];
+
+	memset(out_meta, 0, sizeof(*out_meta));	/* re-initialize to NULL */
+	out_meta->flags = cmd->flags;
+	if (cmd->flags & CMD_WANT_SKB)
+		out_meta->source = cmd;
+	if (cmd->flags & CMD_ASYNC)
+		out_meta->callback = cmd->callback;
+
+	out_cmd->hdr.cmd = cmd->id;
+	memcpy(&out_cmd->cmd.payload, cmd->data, cmd->len);
+
+	/* At this point, the out_cmd now has all of the incoming cmd
+	 * information */
+
+	out_cmd->hdr.flags = 0;
+	out_cmd->hdr.sequence = cpu_to_le16(QUEUE_TO_SEQ(priv->cmd_queue) |
+			INDEX_TO_SEQ(q->write_ptr));
+	if (cmd->flags & CMD_SIZE_HUGE)
+		out_cmd->hdr.sequence |= SEQ_HUGE_FRAME;
+	len = sizeof(struct iwl_device_cmd);
+	if (idx == TFD_CMD_SLOTS)
+		len = IWL_MAX_CMD_SIZE;
+
+#ifdef CONFIG_IWLWIFI_LEGACY_DEBUG
+	switch (out_cmd->hdr.cmd) {
+	case REPLY_TX_LINK_QUALITY_CMD:
+	case SENSITIVITY_CMD:
+		IWL_DEBUG_HC_DUMP(priv,
+				"Sending command %s (#%x), seq: 0x%04X, "
+				"%d bytes at %d[%d]:%d\n",
+				iwl_legacy_get_cmd_string(out_cmd->hdr.cmd),
+				out_cmd->hdr.cmd,
+				le16_to_cpu(out_cmd->hdr.sequence), fix_size,
+				q->write_ptr, idx, priv->cmd_queue);
+		break;
+	default:
+		IWL_DEBUG_HC(priv, "Sending command %s (#%x), seq: 0x%04X, "
+				"%d bytes at %d[%d]:%d\n",
+				iwl_legacy_get_cmd_string(out_cmd->hdr.cmd),
+				out_cmd->hdr.cmd,
+				le16_to_cpu(out_cmd->hdr.sequence), fix_size,
+				q->write_ptr, idx, priv->cmd_queue);
+	}
+#endif
+	txq->need_update = 1;
+
+	if (priv->cfg->ops->lib->txq_update_byte_cnt_tbl)
+		/* Set up entry in queue's byte count circular buffer */
+		priv->cfg->ops->lib->txq_update_byte_cnt_tbl(priv, txq, 0);
+
+	phys_addr = pci_map_single(priv->pci_dev, &out_cmd->hdr,
+				   fix_size, PCI_DMA_BIDIRECTIONAL);
+	dma_unmap_addr_set(out_meta, mapping, phys_addr);
+	dma_unmap_len_set(out_meta, len, fix_size);
+
+	trace_iwlwifi_legacy_dev_hcmd(priv, &out_cmd->hdr,
+						fix_size, cmd->flags);
+
+	priv->cfg->ops->lib->txq_attach_buf_to_tfd(priv, txq,
+						   phys_addr, fix_size, 1,
+						   U32_PAD(cmd->len));
+
+	/* Increment and update queue's write index */
+	q->write_ptr = iwl_legacy_queue_inc_wrap(q->write_ptr, q->n_bd);
+	iwl_legacy_txq_update_write_ptr(priv, txq);
+
+	spin_unlock_irqrestore(&priv->hcmd_lock, flags);
+	return idx;
+}
+
+/**
+ * iwl_legacy_hcmd_queue_reclaim - Reclaim TX command queue entries already Tx'd
+ *
+ * When FW advances 'R' index, all entries between old and new 'R' index
+ * need to be reclaimed. As result, some free space forms.  If there is
+ * enough free space (> low mark), wake the stack that feeds us.
+ */
+static void iwl_legacy_hcmd_queue_reclaim(struct iwl_priv *priv, int txq_id,
+				   int idx, int cmd_idx)
+{
+	struct iwl_tx_queue *txq = &priv->txq[txq_id];
+	struct iwl_queue *q = &txq->q;
+	int nfreed = 0;
+
+	if ((idx >= q->n_bd) || (iwl_legacy_queue_used(q, idx) == 0)) {
+		IWL_ERR(priv, "Read index for DMA queue txq id (%d), index %d, "
+			  "is out of range [0-%d] %d %d.\n", txq_id,
+			  idx, q->n_bd, q->write_ptr, q->read_ptr);
+		return;
+	}
+
+	for (idx = iwl_legacy_queue_inc_wrap(idx, q->n_bd); q->read_ptr != idx;
+	     q->read_ptr = iwl_legacy_queue_inc_wrap(q->read_ptr, q->n_bd)) {
+
+		if (nfreed++ > 0) {
+			IWL_ERR(priv, "HCMD skipped: index (%d) %d %d\n", idx,
+					q->write_ptr, q->read_ptr);
+			queue_work(priv->workqueue, &priv->restart);
+		}
+
+	}
+}
+
+/**
+ * iwl_legacy_tx_cmd_complete - Pull unused buffers off the queue and reclaim them
+ * @rxb: Rx buffer to reclaim
+ *
+ * If an Rx buffer has an async callback associated with it the callback
+ * will be executed.  The attached skb (if present) will only be freed
+ * if the callback returns 1
+ */
+void
+iwl_legacy_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb)
+{
+	struct iwl_rx_packet *pkt = rxb_addr(rxb);
+	u16 sequence = le16_to_cpu(pkt->hdr.sequence);
+	int txq_id = SEQ_TO_QUEUE(sequence);
+	int index = SEQ_TO_INDEX(sequence);
+	int cmd_index;
+	bool huge = !!(pkt->hdr.sequence & SEQ_HUGE_FRAME);
+	struct iwl_device_cmd *cmd;
+	struct iwl_cmd_meta *meta;
+	struct iwl_tx_queue *txq = &priv->txq[priv->cmd_queue];
+
+	/* If a Tx command is being handled and it isn't in the actual
+	 * command queue then there a command routing bug has been introduced
+	 * in the queue management code. */
+	if (WARN(txq_id != priv->cmd_queue,
+		 "wrong command queue %d (should be %d), sequence 0x%X readp=%d writep=%d\n",
+		  txq_id, priv->cmd_queue, sequence,
+		  priv->txq[priv->cmd_queue].q.read_ptr,
+		  priv->txq[priv->cmd_queue].q.write_ptr)) {
+		iwl_print_hex_error(priv, pkt, 32);
+		return;
+	}
+
+	/* If this is a huge cmd, clear the huge flag on the meta.flags
+	 * of the _original_ cmd. So that iwl_legacy_cmd_queue_free won't unmap
+	 * the DMA buffer for the scan (huge) command.
+	 */
+	if (huge) {
+		cmd_index = iwl_legacy_get_cmd_index(&txq->q, index, 0);
+		txq->meta[cmd_index].flags = 0;
+	}
+	cmd_index = iwl_legacy_get_cmd_index(&txq->q, index, huge);
+	cmd = txq->cmd[cmd_index];
+	meta = &txq->meta[cmd_index];
+
+	pci_unmap_single(priv->pci_dev,
+			 dma_unmap_addr(meta, mapping),
+			 dma_unmap_len(meta, len),
+			 PCI_DMA_BIDIRECTIONAL);
+
+	/* Input error checking is done when commands are added to queue. */
+	if (meta->flags & CMD_WANT_SKB) {
+		meta->source->reply_page = (unsigned long)rxb_addr(rxb);
+		rxb->page = NULL;
+	} else if (meta->callback)
+		meta->callback(priv, cmd, pkt);
+
+	iwl_legacy_hcmd_queue_reclaim(priv, txq_id, index, cmd_index);
+
+	if (!(meta->flags & CMD_ASYNC)) {
+		clear_bit(STATUS_HCMD_ACTIVE, &priv->status);
+		IWL_DEBUG_INFO(priv, "Clearing HCMD_ACTIVE for command %s\n",
+			       iwl_legacy_get_cmd_string(cmd->hdr.cmd));
+		wake_up_interruptible(&priv->wait_command_queue);
+	}
+	meta->flags = 0;
+}
+EXPORT_SYMBOL(iwl_legacy_tx_cmd_complete);