iwlwifi: debugFs to enable/disable HT40 support
Add debugfs file to enable/disable HT40(40MHz) channel support.
By default, 40MHz is supported if AP can support the function.
By echo "1" to "disable_ht40" file, iwlwifi driver will disable the
40MHz support and only allow 20MHz channel.
Because the information exchange happen during association time,
so enable/disable ht40 channel only can be performed when it is not
associated with AP.
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 748dc31..7707a26 100644
--- a/drivers/net/wireless/iwlwifi/iwl-debugfs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
@@ -653,6 +653,49 @@
return ret;
}
+static ssize_t iwl_dbgfs_disable_ht40_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 ht40;
+
+ 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", &ht40) != 1)
+ return -EFAULT;
+ if (!iwl_is_associated(priv))
+ priv->disable_ht40 = ht40 ? true : false;
+ else {
+ IWL_ERR(priv, "Sta associated with AP - "
+ "Change to 40MHz channel support is not allowed\n");
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+static ssize_t iwl_dbgfs_disable_ht40_read(struct file *file,
+ char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct iwl_priv *priv = (struct iwl_priv *)file->private_data;
+ char buf[100];
+ int pos = 0;
+ const size_t bufsz = sizeof(buf);
+ ssize_t ret;
+
+ pos += scnprintf(buf + pos, bufsz - pos,
+ "11n 40MHz Mode: %s\n",
+ priv->disable_ht40 ? "Disabled" : "Enabled");
+ ret = simple_read_from_buffer(user_buf, count, ppos, buf, pos);
+ return ret;
+}
+
DEBUGFS_READ_WRITE_FILE_OPS(sram);
DEBUGFS_WRITE_FILE_OPS(log_event);
DEBUGFS_READ_FILE_OPS(nvm);
@@ -667,6 +710,7 @@
DEBUGFS_READ_FILE_OPS(led);
#endif
DEBUGFS_READ_FILE_OPS(thermal_throttling);
+DEBUGFS_READ_WRITE_FILE_OPS(disable_ht40);
/*
* Create the debugfs files and directories
@@ -708,6 +752,7 @@
DEBUGFS_ADD_FILE(led, data);
#endif
DEBUGFS_ADD_FILE(thermal_throttling, data);
+ DEBUGFS_ADD_FILE(disable_ht40, data);
DEBUGFS_ADD_BOOL(disable_sensitivity, rf, &priv->disable_sens_cal);
DEBUGFS_ADD_BOOL(disable_chain_noise, rf,
&priv->disable_chain_noise_cal);
@@ -747,6 +792,7 @@
DEBUGFS_REMOVE(priv->dbgfs->dbgfs_data_files.file_led);
#endif
DEBUGFS_REMOVE(priv->dbgfs->dbgfs_data_files.file_thermal_throttling);
+ DEBUGFS_REMOVE(priv->dbgfs->dbgfs_data_files.file_disable_ht40);
DEBUGFS_REMOVE(priv->dbgfs->dir_data);
DEBUGFS_REMOVE(priv->dbgfs->dbgfs_rf_files.file_disable_sensitivity);
DEBUGFS_REMOVE(priv->dbgfs->dbgfs_rf_files.file_disable_chain_noise);