X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fnet%2Fwireless%2Fiwlwifi%2Fiwl-calib.c;h=8b516c5ff0bb5f2ba4ad8143aa159968478877bc;hb=33eaf788345c0311ab48ae62673c05f59fb09bb3;hp=845831ac053e2fa4bb320abb5024b87d4a5632b9;hpb=586fac13f8685bf9dfb32e1ee98bfb14f0dd0061;p=pandora-kernel.git

diff --git a/drivers/net/wireless/iwlwifi/iwl-calib.c b/drivers/net/wireless/iwlwifi/iwl-calib.c
index 845831ac053e..8b516c5ff0bb 100644
--- a/drivers/net/wireless/iwlwifi/iwl-calib.c
+++ b/drivers/net/wireless/iwlwifi/iwl-calib.c
@@ -60,6 +60,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *****************************************************************************/
 
+#include <linux/slab.h>
 #include <net/mac80211.h>
 
 #include "iwl-dev.h"
@@ -807,6 +808,18 @@ void iwl_chain_noise_calibration(struct iwl_priv *priv,
 		}
 	}
 
+	/*
+	 * The above algorithm sometimes fails when the ucode
+	 * reports 0 for all chains. It's not clear why that
+	 * happens to start with, but it is then causing trouble
+	 * because this can make us enable more chains than the
+	 * hardware really has.
+	 *
+	 * To be safe, simply mask out any chains that we know
+	 * are not on the device.
+	 */
+	active_chains &= priv->hw_params.valid_rx_ant;
+
 	num_tx_chains = 0;
 	for (i = 0; i < NUM_RX_CHAINS; i++) {
 		/* loops on all the bits of