iwlwifi: update reply_statistics_cmd with 'clear' parameter

When issue REPLY_STATISTICS_CMD to uCode, two possible flag
can be set in the configuration flags

bit 0: Clear statistics
       0: Do not clear Statistics counters
       1: Clear to zero Statistics counters

Allow "clear" parameter to be set from the caller.

Add debugfs file to clear the statistics counters to help monitor and
debug the uCode behavior.

Signed-off-by: Wey-Yi Guy <wey-yi.w.guy@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-debugfs.c b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
index 8784911..45a5edd 100644
--- a/drivers/net/wireless/iwlwifi/iwl-debugfs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
@@ -1042,10 +1042,6 @@
 	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 }
 
-#define UCODE_STATISTICS_CLEAR_MSK		(0x1 << 0)
-#define UCODE_STATISTICS_FREQUENCY_MSK		(0x1 << 1)
-#define UCODE_STATISTICS_NARROW_BAND_MSK	(0x1 << 2)
-
 static int iwl_dbgfs_statistics_flag(struct iwl_priv *priv, char *buf,
 				     int bufsz)
 {
@@ -1092,7 +1088,7 @@
 
 	/* make request to uCode to retrieve statistics information */
 	mutex_lock(&priv->mutex);
-	ret = iwl_send_statistics_request(priv, 0);
+	ret = iwl_send_statistics_request(priv, CMD_SYNC, false);
 	mutex_unlock(&priv->mutex);
 
 	if (ret) {
@@ -1398,7 +1394,7 @@
 
 	/* make request to uCode to retrieve statistics information */
 	mutex_lock(&priv->mutex);
-	ret = iwl_send_statistics_request(priv, 0);
+	ret = iwl_send_statistics_request(priv, CMD_SYNC, false);
 	mutex_unlock(&priv->mutex);
 
 	if (ret) {
@@ -1542,7 +1538,7 @@
 
 	/* make request to uCode to retrieve statistics information */
 	mutex_lock(&priv->mutex);
-	ret = iwl_send_statistics_request(priv, 0);
+	ret = iwl_send_statistics_request(priv, CMD_SYNC, false);
 	mutex_unlock(&priv->mutex);
 
 	if (ret) {
@@ -1770,7 +1766,7 @@
 	else {
 		/* make request to uCode to retrieve statistics information */
 		mutex_lock(&priv->mutex);
-		ret = iwl_send_statistics_request(priv, 0);
+		ret = iwl_send_statistics_request(priv, CMD_SYNC, false);
 		mutex_unlock(&priv->mutex);
 
 		if (ret) {
@@ -1828,6 +1824,30 @@
 	return simple_read_from_buffer(user_buf, count, ppos, buf, pos);
 }
 
+static ssize_t iwl_dbgfs_clear_statistics_write(struct file *file,
+					 const char __user *user_buf,
+					 size_t count, loff_t *ppos)
+{
+	struct iwl_priv *priv = file->private_data;
+	char buf[8];
+	int buf_size;
+	int clear;
+
+	memset(buf, 0, sizeof(buf));
+	buf_size = min(count, sizeof(buf) -  1);
+	if (copy_from_user(buf, user_buf, buf_size))
+		return -EFAULT;
+	if (sscanf(buf, "%d", &clear) != 1)
+		return -EFAULT;
+
+	/* make request to uCode to retrieve statistics information */
+	mutex_lock(&priv->mutex);
+	iwl_send_statistics_request(priv, CMD_SYNC, true);
+	mutex_unlock(&priv->mutex);
+
+	return count;
+}
+
 DEBUGFS_READ_WRITE_FILE_OPS(rx_statistics);
 DEBUGFS_READ_WRITE_FILE_OPS(tx_statistics);
 DEBUGFS_READ_WRITE_FILE_OPS(traffic_log);
@@ -1840,6 +1860,7 @@
 DEBUGFS_READ_FILE_OPS(chain_noise);
 DEBUGFS_READ_FILE_OPS(tx_power);
 DEBUGFS_READ_FILE_OPS(power_save_status);
+DEBUGFS_WRITE_FILE_OPS(clear_statistics);
 
 /*
  * Create the debugfs files and directories
@@ -1888,6 +1909,7 @@
 	DEBUGFS_ADD_FILE(tx_queue, debug);
 	DEBUGFS_ADD_FILE(tx_power, debug);
 	DEBUGFS_ADD_FILE(power_save_status, debug);
+	DEBUGFS_ADD_FILE(clear_statistics, debug);
 	if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) != CSR_HW_REV_TYPE_3945) {
 		DEBUGFS_ADD_FILE(ucode_rx_stats, debug);
 		DEBUGFS_ADD_FILE(ucode_tx_stats, debug);
@@ -1941,6 +1963,7 @@
 	DEBUGFS_REMOVE(priv->dbgfs->dbgfs_debug_files.file_tx_queue);
 	DEBUGFS_REMOVE(priv->dbgfs->dbgfs_debug_files.file_tx_power);
 	DEBUGFS_REMOVE(priv->dbgfs->dbgfs_debug_files.file_power_save_status);
+	DEBUGFS_REMOVE(priv->dbgfs->dbgfs_debug_files.file_clear_statistics);
 	if ((priv->hw_rev & CSR_HW_REV_TYPE_MSK) != CSR_HW_REV_TYPE_3945) {
 		DEBUGFS_REMOVE(priv->dbgfs->dbgfs_debug_files.
 			file_ucode_rx_stats);