iwlwifi: Add iwl_write8()

To support byte writes to CSR_INT_COALESCING and CSR_INT_PERIODIC registers,
add iwl_write8(), including debug/trace support.

Signed-off-by: Ben Cahill <ben.m.cahill@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/iwlwifi/iwl-devtrace.h b/drivers/net/wireless/iwlwifi/iwl-devtrace.h
index 8c71592..f2d4b01 100644
--- a/drivers/net/wireless/iwlwifi/iwl-devtrace.h
+++ b/drivers/net/wireless/iwlwifi/iwl-devtrace.h
@@ -32,6 +32,22 @@
 	TP_printk("[%p] read io[%#x] = %#x", __entry->priv, __entry->offs, __entry->val)
 );
 
+TRACE_EVENT(iwlwifi_dev_iowrite8,
+	TP_PROTO(struct iwl_priv *priv, u32 offs, u8 val),
+	TP_ARGS(priv, offs, val),
+	TP_STRUCT__entry(
+		PRIV_ENTRY
+		__field(u32, offs)
+		__field(u8, val)
+	),
+	TP_fast_assign(
+		PRIV_ASSIGN;
+		__entry->offs = offs;
+		__entry->val = val;
+	),
+	TP_printk("[%p] write io[%#x] = %#x)", __entry->priv, __entry->offs, __entry->val)
+);
+
 TRACE_EVENT(iwlwifi_dev_iowrite32,
 	TP_PROTO(struct iwl_priv *priv, u32 offs, u32 val),
 	TP_ARGS(priv, offs, val),