Re: [PATCH RESEND] mwifiex: fix regression issue for usb interface

["John W. Linville" <linville@tuxdriver.com>]

I have the original patch.  Merging is a bit stalled at the moment,
related to last weeks rebase of the wireless tree...

On Mon, Jun 10, 2013 at 03:39:41PM -0700, Bing Zhao wrote:
> From: Amitkumar Karwar <akarwar@marvell.com>
> 
> PATCH "mwifiex: scan delay timer cleanup in unload path" adds code
> to cancel scan delay timer in unload path. It causes a regression
> for USB interface.
> 
> USB8797 card gets enumerated twice. First enumeration is for
> firmware download and second enumeration expects firmware
> initialization.
> 
> It was observed that we are trying del_timer_sync() without setting
> up the timer when remove handler is called after first enumeration.
> 
> This patch moves setup_timer() call to appropriate place so that
> timer is setup for both the enumerations.
> 
> Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
> Signed-off-by: Bing Zhao <bzhao@marvell.com>
> ---
>  drivers/net/wireless/mwifiex/init.c | 81 ------------------------------------
>  drivers/net/wireless/mwifiex/main.c | 82 +++++++++++++++++++++++++++++++++++++
>  2 files changed, 82 insertions(+), 81 deletions(-)
> 
> diff --git a/drivers/net/wireless/mwifiex/init.c b/drivers/net/wireless/mwifiex/init.c
> index c7f11c0..2fe31dc 100644
> --- a/drivers/net/wireless/mwifiex/init.c
> +++ b/drivers/net/wireless/mwifiex/init.c
> @@ -52,84 +52,6 @@ static int mwifiex_add_bss_prio_tbl(struct mwifiex_private *priv)
>  	return 0;
>  }
>  
> -static void scan_delay_timer_fn(unsigned long data)
> -{
> -	struct mwifiex_private *priv = (struct mwifiex_private *)data;
> -	struct mwifiex_adapter *adapter = priv->adapter;
> -	struct cmd_ctrl_node *cmd_node, *tmp_node;
> -	unsigned long flags;
> -
> -	if (adapter->surprise_removed)
> -		return;
> -
> -	if (adapter->scan_delay_cnt == MWIFIEX_MAX_SCAN_DELAY_CNT) {
> -		/*
> -		 * Abort scan operation by cancelling all pending scan
> -		 * commands
> -		 */
> -		spin_lock_irqsave(&adapter->scan_pending_q_lock, flags);
> -		list_for_each_entry_safe(cmd_node, tmp_node,
> -					 &adapter->scan_pending_q, list) {
> -			list_del(&cmd_node->list);
> -			mwifiex_insert_cmd_to_free_q(adapter, cmd_node);
> -		}
> -		spin_unlock_irqrestore(&adapter->scan_pending_q_lock, flags);
> -
> -		spin_lock_irqsave(&adapter->mwifiex_cmd_lock, flags);
> -		adapter->scan_processing = false;
> -		adapter->scan_delay_cnt = 0;
> -		adapter->empty_tx_q_cnt = 0;
> -		spin_unlock_irqrestore(&adapter->mwifiex_cmd_lock, flags);
> -
> -		if (priv->scan_request) {
> -			dev_dbg(adapter->dev, "info: aborting scan\n");
> -			cfg80211_scan_done(priv->scan_request, 1);
> -			priv->scan_request = NULL;
> -		} else {
> -			priv->scan_aborting = false;
> -			dev_dbg(adapter->dev, "info: scan already aborted\n");
> -		}
> -		goto done;
> -	}
> -
> -	if (!atomic_read(&priv->adapter->is_tx_received)) {
> -		adapter->empty_tx_q_cnt++;
> -		if (adapter->empty_tx_q_cnt == MWIFIEX_MAX_EMPTY_TX_Q_CNT) {
> -			/*
> -			 * No Tx traffic for 200msec. Get scan command from
> -			 * scan pending queue and put to cmd pending queue to
> -			 * resume scan operation
> -			 */
> -			adapter->scan_delay_cnt = 0;
> -			adapter->empty_tx_q_cnt = 0;
> -			spin_lock_irqsave(&adapter->scan_pending_q_lock, flags);
> -			cmd_node = list_first_entry(&adapter->scan_pending_q,
> -						    struct cmd_ctrl_node, list);
> -			list_del(&cmd_node->list);
> -			spin_unlock_irqrestore(&adapter->scan_pending_q_lock,
> -					       flags);
> -
> -			mwifiex_insert_cmd_to_pending_q(adapter, cmd_node,
> -							true);
> -			queue_work(adapter->workqueue, &adapter->main_work);
> -			goto done;
> -		}
> -	} else {
> -		adapter->empty_tx_q_cnt = 0;
> -	}
> -
> -	/* Delay scan operation further by 20msec */
> -	mod_timer(&priv->scan_delay_timer, jiffies +
> -		  msecs_to_jiffies(MWIFIEX_SCAN_DELAY_MSEC));
> -	adapter->scan_delay_cnt++;
> -
> -done:
> -	if (atomic_read(&priv->adapter->is_tx_received))
> -		atomic_set(&priv->adapter->is_tx_received, false);
> -
> -	return;
> -}
> -
>  /*
>   * This function initializes the private structure and sets default
>   * values to the members.
> @@ -211,9 +133,6 @@ int mwifiex_init_priv(struct mwifiex_private *priv)
>  
>  	priv->scan_block = false;
>  
> -	setup_timer(&priv->scan_delay_timer, scan_delay_timer_fn,
> -		    (unsigned long)priv);
> -
>  	return mwifiex_add_bss_prio_tbl(priv);
>  }
>  
> diff --git a/drivers/net/wireless/mwifiex/main.c b/drivers/net/wireless/mwifiex/main.c
> index 5bc7ef8..4858719 100644
> --- a/drivers/net/wireless/mwifiex/main.c
> +++ b/drivers/net/wireless/mwifiex/main.c
> @@ -28,6 +28,84 @@ const char driver_version[] = "mwifiex " VERSION " (%s) ";
>  static char *cal_data_cfg;
>  module_param(cal_data_cfg, charp, 0);
>  
> +static void scan_delay_timer_fn(unsigned long data)
> +{
> +	struct mwifiex_private *priv = (struct mwifiex_private *)data;
> +	struct mwifiex_adapter *adapter = priv->adapter;
> +	struct cmd_ctrl_node *cmd_node, *tmp_node;
> +	unsigned long flags;
> +
> +	if (adapter->surprise_removed)
> +		return;
> +
> +	if (adapter->scan_delay_cnt == MWIFIEX_MAX_SCAN_DELAY_CNT) {
> +		/*
> +		 * Abort scan operation by cancelling all pending scan
> +		 * commands
> +		 */
> +		spin_lock_irqsave(&adapter->scan_pending_q_lock, flags);
> +		list_for_each_entry_safe(cmd_node, tmp_node,
> +					 &adapter->scan_pending_q, list) {
> +			list_del(&cmd_node->list);
> +			mwifiex_insert_cmd_to_free_q(adapter, cmd_node);
> +		}
> +		spin_unlock_irqrestore(&adapter->scan_pending_q_lock, flags);
> +
> +		spin_lock_irqsave(&adapter->mwifiex_cmd_lock, flags);
> +		adapter->scan_processing = false;
> +		adapter->scan_delay_cnt = 0;
> +		adapter->empty_tx_q_cnt = 0;
> +		spin_unlock_irqrestore(&adapter->mwifiex_cmd_lock, flags);
> +
> +		if (priv->scan_request) {
> +			dev_dbg(adapter->dev, "info: aborting scan\n");
> +			cfg80211_scan_done(priv->scan_request, 1);
> +			priv->scan_request = NULL;
> +		} else {
> +			priv->scan_aborting = false;
> +			dev_dbg(adapter->dev, "info: scan already aborted\n");
> +		}
> +		goto done;
> +	}
> +
> +	if (!atomic_read(&priv->adapter->is_tx_received)) {
> +		adapter->empty_tx_q_cnt++;
> +		if (adapter->empty_tx_q_cnt == MWIFIEX_MAX_EMPTY_TX_Q_CNT) {
> +			/*
> +			 * No Tx traffic for 200msec. Get scan command from
> +			 * scan pending queue and put to cmd pending queue to
> +			 * resume scan operation
> +			 */
> +			adapter->scan_delay_cnt = 0;
> +			adapter->empty_tx_q_cnt = 0;
> +			spin_lock_irqsave(&adapter->scan_pending_q_lock, flags);
> +			cmd_node = list_first_entry(&adapter->scan_pending_q,
> +						    struct cmd_ctrl_node, list);
> +			list_del(&cmd_node->list);
> +			spin_unlock_irqrestore(&adapter->scan_pending_q_lock,
> +					       flags);
> +
> +			mwifiex_insert_cmd_to_pending_q(adapter, cmd_node,
> +							true);
> +			queue_work(adapter->workqueue, &adapter->main_work);
> +			goto done;
> +		}
> +	} else {
> +		adapter->empty_tx_q_cnt = 0;
> +	}
> +
> +	/* Delay scan operation further by 20msec */
> +	mod_timer(&priv->scan_delay_timer, jiffies +
> +		  msecs_to_jiffies(MWIFIEX_SCAN_DELAY_MSEC));
> +	adapter->scan_delay_cnt++;
> +
> +done:
> +	if (atomic_read(&priv->adapter->is_tx_received))
> +		atomic_set(&priv->adapter->is_tx_received, false);
> +
> +	return;
> +}
> +
>  /*
>   * This function registers the device and performs all the necessary
>   * initializations.
> @@ -75,6 +153,10 @@ static int mwifiex_register(void *card, struct mwifiex_if_ops *if_ops,
>  
>  		adapter->priv[i]->adapter = adapter;
>  		adapter->priv_num++;
> +
> +		setup_timer(&adapter->priv[i]->scan_delay_timer,
> +			    scan_delay_timer_fn,
> +			    (unsigned long)adapter->priv[i]);
>  	}
>  	mwifiex_init_lock_list(adapter);
>  
> -- 
> 1.8.2.3
> 
> 

-- 
John W. Linville		Someday the world will need a hero, and you
linville@tuxdriver.com			might be all we have.  Be ready.