iwlagn: map command buffers BIDI

Evidently, the device sometimes wants to write back
to command buffers, even if I see no reason why it
should. Allow it to do that.

Tested-by: Andy Lutomirski <luto@mit.edu>
Tested-by: Kyle McMartin <kyle@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@intel.com>

1 files changed, 10 insertions, 7 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c
index 8f20065e6dac..47074315903e 100644
--- a/drivers/net/wireless/iwlwifi/iwl-tx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-tx.c
@@ -126,7 +126,7 @@ static inline u8 iwl_tfd_get_num_tbs(struct iwl_tfd *tfd)
 }
 
 static void iwlagn_unmap_tfd(struct iwl_priv *priv, struct iwl_cmd_meta *meta,
-                             struct iwl_tfd *tfd)
+                             struct iwl_tfd *tfd, enum dma_data_direction dma_dir)
 {
         struct pci_dev *dev = priv->pci_dev;
         int i;
@@ -151,7 +151,7 @@ static void iwlagn_unmap_tfd(struct iwl_priv *priv, struct iwl_cmd_meta *meta,
         /* Unmap chunks, if any. */
         for (i = 1; i < num_tbs; i++)
                 pci_unmap_single(dev, iwl_tfd_tb_get_addr(tfd, i),
-                                iwl_tfd_tb_get_len(tfd, i), PCI_DMA_TODEVICE);
+                                iwl_tfd_tb_get_len(tfd, i), dma_dir);
 }
 
 /**
@@ -167,7 +167,8 @@ void iwlagn_txq_free_tfd(struct iwl_priv *priv, struct iwl_tx_queue *txq)
         struct iwl_tfd *tfd_tmp = txq->tfds;
         int index = txq->q.read_ptr;
 
-        iwlagn_unmap_tfd(priv, &txq->meta[index], &tfd_tmp[index]);
+        iwlagn_unmap_tfd(priv, &txq->meta[index], &tfd_tmp[index],
+                         DMA_TO_DEVICE);
 
         /* free SKB */
         if (txq->txb) {
@@ -310,7 +311,8 @@ void iwl_cmd_queue_unmap(struct iwl_priv *priv)
                 i = get_cmd_index(q, q->read_ptr);
 
                 if (txq->meta[i].flags & CMD_MAPPED) {
-                        iwlagn_unmap_tfd(priv, &txq->meta[i], &txq->tfds[i]);
+                        iwlagn_unmap_tfd(priv, &txq->meta[i], &txq->tfds[i],
+                                         DMA_BIDIRECTIONAL);
                         txq->meta[i].flags = 0;
                 }
 
@@ -692,10 +694,11 @@ int iwl_enqueue_hcmd(struct iwl_priv *priv, struct iwl_host_cmd *cmd)
                 if (!(cmd->dataflags[i] & IWL_HCMD_DFL_NOCOPY))
                         continue;
                 phys_addr = pci_map_single(priv->pci_dev, (void *)cmd->data[i],
-                                           cmd->len[i], PCI_DMA_TODEVICE);
+                                           cmd->len[i], DMA_BIDIRECTIONAL);
                 if (pci_dma_mapping_error(priv->pci_dev, phys_addr)) {
                         iwlagn_unmap_tfd(priv, out_meta,
-                                         &txq->tfds[q->write_ptr]);
+                                         &txq->tfds[q->write_ptr],
+                                         DMA_BIDIRECTIONAL);
                         idx = -ENOMEM;
                         goto out;
                 }
@@ -799,7 +802,7 @@ void iwl_tx_cmd_complete(struct iwl_priv *priv, struct iwl_rx_mem_buffer *rxb)
         cmd = txq->cmd[cmd_index];
         meta = &txq->meta[cmd_index];
 
-        iwlagn_unmap_tfd(priv, meta, &txq->tfds[index]);
+        iwlagn_unmap_tfd(priv, meta, &txq->tfds[index], DMA_BIDIRECTIONAL);
 
         /* Input error checking is done when commands are added to queue. */
         if (meta->flags & CMD_WANT_SKB) {