[PATCH 12/14] iwlwifi: debugFs to enable/disable 40MHz channel support

Reinette Chatre
2009-07-24T18:13:18Z

From: Wey-Yi Guy <wey-yi.w.guy@intel.com>

Add debugfs file to enable/disable Fat(40MHz) channel support.
By default, 40MHz is supported if AP can support the function.

By echo "1" to "disable_fat_mode" file, iwlwifi driver will disable the 40MHz
support and only allow 20MHz channel.

Because the information exchange happen during association time,
so enable/disable fat 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>
---
drivers/net/wireless/iwlwifi/iwl-core.c | 4 ++
drivers/net/wireless/iwlwifi/iwl-debug.h | 1 +
drivers/net/wireless/iwlwifi/iwl-debugfs.c | 46 ++++++++++++++++++++++++++++
drivers/net/wireless/iwlwifi/iwl-dev.h | 1 +
4 files changed, 52 insertions(+), 0 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index 710dd41..edfdbe8 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -632,6 +632,10 @@ u8 iwl_is_fat_tx_allowed(struct iwl_priv *priv,
if (!sta_ht_inf->ht_supported)
return 0;
}
+#ifdef CONFIG_IWLWIFI_DEBUG
+ if (priv->disable_fat)
+ return 0;
+#endif
return iwl_is_channel_extension(priv, priv->band,
le16_to_cpu(priv->staging_rxon.channel),
iwl_ht_conf->extension_chan_offset);
diff --git a/drivers/net/wireless/iwlwifi/iwl-debug.h b/drivers/net/wireless/iwlwifi/iwl-debug.h
index 609a681..2e10da3 100644
--- a/drivers/net/wireless/iwlwifi/iwl-debug.h
+++ b/drivers/net/wireless/iwlwifi/iwl-debug.h
@@ -88,6 +88,7 @@ struct iwl_debugfs {
#ifdef CONFIG_IWLWIFI_LEDS
struct dentry *file_led;
#endif
+ struct dentry *file_disable_fat_mode;
} dbgfs_data_files;
struct dir_rf_files {
struct dentry *file_disable_sensitivity;
diff --git a/drivers/net/wireless/iwlwifi/iwl-debugfs.c b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
index 748dc31..03486d5 100644
--- a/drivers/net/wireless/iwlwifi/iwl-debugfs.c
+++ b/drivers/net/wireless/iwlwifi/iwl-debugfs.c
@@ -653,6 +653,49 @@ static ssize_t iwl_dbgfs_thermal_throttling_read(struct file *file,
return ret;
}

+static ssize_t iwl_dbgfs_disable_fat_mode_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 fat_mode;
+
+ 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", &fat_mode) != 1)
+ return -EFAULT;
+ if (!iwl_is_associated(priv))
+ priv->disable_fat = fat_mode ? true : false;
+ else {
+ IWL_ERR(priv, "Sta associated with AP - "
+ "Change fat mode is not allowed\n");
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+static ssize_t iwl_dbgfs_disable_fat_mode_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_fat ? "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(qos);
DEBUGFS_READ_FILE_OPS(led);
#endif
DEBUGFS_READ_FILE_OPS(thermal_throttling);
+DEBUGFS_READ_WRITE_FILE_OPS(disable_fat_mode);

/*
* Create the debugfs files and directories
@@ -708,6 +752,7 @@ int iwl_dbgfs_register(struct iwl_priv *priv, const char *name)
DEBUGFS_ADD_FILE(led, data);
#endif
DEBUGFS_ADD_FILE(thermal_throttling, data);
+ DEBUGFS_ADD_FILE(disable_fat_mode, 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 @@ void iwl_dbgfs_unregister(struct iwl_priv *priv)
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_fat_mode);
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);
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index facbc3d..6101d12 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -1164,6 +1164,7 @@ struct iwl_priv {
/* debugging info */
u32 framecnt_to_us;
atomic_t restrict_refcnt;
+ bool disable_fat;
#ifdef CONFIG_IWLWIFI_DEBUGFS
/* debugfs */
struct iwl_debugfs *dbgfs;
--
1.5.6.3