2 files changed, 26 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-prph.h b/drivers/net/wireless/iwlwifi/iwl-prph.h
index d69b0fb0a434..100bd0d79681 100644
--- a/drivers/net/wireless/iwlwifi/iwl-prph.h
+++ b/drivers/net/wireless/iwlwifi/iwl-prph.h
@@ -277,4 +277,8 @@ static inline unsigned int SCD_QUEUE_STATUS_BITS(unsigned int chnl)
 
 /*********************** END TX SCHEDULER *************************************/
 
+/* Oscillator clock */
+#define OSC_CLK                         (0xa04068)
+#define OSC_CLK_FORCE_CONTROL           (0x8)
+
 #endif                          /* __iwl_prph_h__ */
diff --git a/drivers/net/wireless/iwlwifi/pcie/trans.c b/drivers/net/wireless/iwlwifi/pcie/trans.c
index 16f66c1a23de..f9507807b486 100644
--- a/drivers/net/wireless/iwlwifi/pcie/trans.c
+++ b/drivers/net/wireless/iwlwifi/pcie/trans.c
@@ -178,6 +178,28 @@ static int iwl_pcie_apm_init(struct iwl_trans *trans)
                 goto out;
         }
 
+        if (trans->cfg->host_interrupt_operation_mode) {
+                /*
+                 * This is a bit of an abuse - This is needed for 7260 / 3160
+                 * only check host_interrupt_operation_mode even if this is
+                 * not related to host_interrupt_operation_mode.
+                 *
+                 * Enable the oscillator to count wake up time for L1 exit. This
+                 * consumes slightly more power (100uA) - but allows to be sure
+                 * that we wake up from L1 on time.
+                 *
+                 * This looks weird: read twice the same register, discard the
+                 * value, set a bit, and yet again, read that same register
+                 * just to discard the value. But that's the way the hardware
+                 * seems to like it.
+                 */
+                iwl_read_prph(trans, OSC_CLK);
+                iwl_read_prph(trans, OSC_CLK);
+                iwl_set_bits_prph(trans, OSC_CLK, OSC_CLK_FORCE_CONTROL);
+                iwl_read_prph(trans, OSC_CLK);
+                iwl_read_prph(trans, OSC_CLK);
+        }
+
         /*
          * Enable DMA clock and wait for it to stabilize.
          *