iwlwifi: fix DMA channel number in iwl_txq_ctx_stop

The patch fixes the misuse of DMA channel number by Tx queue number in
iwl_tx_ctx_stop().

The problem was originally reported by Wu Fengguang who complains
iwlagn driver takes too long time when issuing `ifconfig wlan0 down`.
The patch now decreases the interface bring down time from 2 seconds
to 0.8 second.

This fixes bugs:
http://bugzilla.kernel.org/show_bug.cgi?id=11956
http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1790

Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Tested-by: Fengguang Wu <fengguang.wu@intel.com>
Acked-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index 846b8b01fa73..5f6805bfec3f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -508,6 +508,7 @@ struct iwl_sensitivity_ranges {
 /**
  * struct iwl_hw_params
  * @max_txq_num: Max # Tx queues supported
+ * @dma_chnl_num: Number of Tx DMA/FIFO channels
  * @scd_bc_tbls_size: size of scheduler byte count tables
  * @tx/rx_chains_num: Number of TX/RX chains
  * @valid_tx/rx_ant: usable antennas
@@ -525,7 +526,8 @@ struct iwl_sensitivity_ranges {
  * @struct iwl_sensitivity_ranges: range of sensitivity values
  */
 struct iwl_hw_params {
-        u16 max_txq_num;
+        u8 max_txq_num;
+        u8 dma_chnl_num;
         u16 scd_bc_tbls_size;
         u8  tx_chains_num;
         u8  rx_chains_num;