[PATCH 2/2] ath9k_htc: Fix unnecessary warnings on card removal

[PATCH 2/2] ath9k_htc: Fix unnecessary warnings on card removal

[Rajkumar Manoharan]

Avoid register read/write operations when
the card is unplaugged. Otherwise results in
unnecessary warnings.

usb 1-1: USB disconnect, address 10
ath: Failed to wakeup in 500us
------------[ cut here ]------------
WARNING: at drivers/net/wireless/ath/ath9k/hw.c:1616
ath9k_hw_setpower+0x61f/0x630 [ath9k_hw]()
Pid: 1830, comm: khubd Tainted: G        W   2.6.37-rc5-wl #33
Call Trace:
[<ffffffff8105018a>] warn_slowpath_common+0x7a/0xb0
[<ffffffffa0621c90>] ? ath9k_regwrite+0x0/0x190 [ath9k_htc]
[<ffffffff810501d5>] warn_slowpath_null+0x15/0x20
[<ffffffffa05d06ef>] ath9k_hw_setpower+0x61f/0x630 [ath9k_hw]
[<ffffffffa061f25c>] ath9k_htc_ps_wakeup+0x5c/0x60 [ath9k_htc]
[<ffffffffa062082e>] ath9k_htc_remove_interface+0x4e/0xe0 [ath9k_htc]
[<ffffffff81345329>] ? mutex_unlock+0x9/0x10
[<ffffffffa055bbe7>] ? ieee80211_free_keys+0x87/0xa0 [mac80211]
[<ffffffffa054e845>] ieee80211_do_stop+0x4f5/0x540 [mac80211]
[<ffffffff8134678f>] ? _raw_spin_unlock_bh+0x1f/0x30
[<ffffffff812b6983>] ? dev_deactivate+0x1c3/0x1e0
[<ffffffffa054e8a5>] ieee80211_stop+0x15/0x20 [mac80211]
[<ffffffff8129d226>] __dev_close+0x56/0x90
[<ffffffff8129d27a>] dev_close+0x1a/0x50

Signed-off-by: Rajkumar Manoharan <rmanoharan@atheros.com>
---
 drivers/net/wireless/ath/ath9k/htc.h          |    1 -
 drivers/net/wireless/ath/ath9k/htc_drv_init.c |    6 ++----
 drivers/net/wireless/ath/ath9k/htc_drv_main.c |   24 +++++++++++++++++++++++-
 drivers/net/wireless/ath/ath9k/wmi.c          |    2 +-
 4 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
index fdf9d5f..d90838a 100644
--- a/drivers/net/wireless/ath/ath9k/htc.h
+++ b/drivers/net/wireless/ath/ath9k/htc.h
@@ -339,7 +339,6 @@ void ath_htc_cancel_btcoex_work(struct ath9k_htc_priv *priv);
 #define OP_ASSOCIATED		   BIT(7)
 #define OP_ENABLE_BEACON	   BIT(8)
 #define OP_LED_DEINIT		   BIT(9)
-#define OP_UNPLUGGED		   BIT(10)
 #define OP_BT_PRIORITY_DETECTED	   BIT(11)
 #define OP_BT_SCAN		   BIT(12)
 
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_init.c b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
index 0f6be35..8a73dc2 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_init.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_init.c
@@ -632,6 +632,7 @@ static int ath9k_init_priv(struct ath9k_htc_priv *priv,
 	ah->hw_version.subsysid = 0; /* FIXME */
 	ah->hw_version.usbdev = drv_info;
 	ah->ah_flags |= AH_USE_EEPROM;
+	ah->ah_flags &= ~AH_UNPLUGGED;
 	priv->ah = ah;
 
 	common = ath9k_hw_common(ah);
@@ -851,9 +852,6 @@ int ath9k_htc_probe_device(struct htc_target *htc_handle, struct device *dev,
 	if (ret)
 		goto err_init;
 
-	/* The device may have been unplugged earlier. */
-	priv->op_flags &= ~OP_UNPLUGGED;
-
 	ret = ath9k_init_device(priv, devid, product, drv_info);
 	if (ret)
 		goto err_init;
@@ -873,7 +871,7 @@ void ath9k_htc_disconnect_device(struct htc_target *htc_handle, bool hotunplug)
 
 		/* Check if the device has been yanked out. */
 		if (hotunplug)
-			htc_handle->drv_priv->op_flags |= OP_UNPLUGGED;
+			htc_handle->drv_priv->ah->ah_flags |= AH_UNPLUGGED;
 
 		ath9k_deinit_device(htc_handle->drv_priv);
 		ath9k_deinit_wmi(htc_handle->drv_priv);
diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_main.c b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
index dd17909..f6e64c9 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_main.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
@@ -1110,6 +1110,11 @@ static int ath9k_htc_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
 	struct ath9k_htc_priv *priv = hw->priv;
 	int padpos, padsize, ret;
 
+	if (priv->ah->ah_flags & AH_UNPLUGGED) {
+		ath_dbg(ath9k_hw_common(priv->ah), ATH_DBG_ANY,
+			"Device no present, can not xmit\n");
+		goto fail_tx;
+	}
 	hdr = (struct ieee80211_hdr *) skb->data;
 
 	/* Add the padding after the header if this is not already done */
@@ -1231,6 +1236,12 @@ static void ath9k_htc_stop(struct ieee80211_hw *hw)
 	cancel_delayed_work_sync(&priv->ath9k_led_blink_work);
 	ath9k_led_stop_brightness(priv);
 
+	if (ah->ah_flags & AH_UNPLUGGED) {
+		ath_dbg(common, ATH_DBG_ANY, "Device not present\n");
+		mutex_unlock(&priv->mutex);
+		return;
+	}
+
 	ath9k_htc_ps_wakeup(priv);
 	htc_stop(priv->htc);
 	WMI_CMD(WMI_DISABLE_INTR_CMDID);
@@ -1348,6 +1359,11 @@ static void ath9k_htc_remove_interface(struct ieee80211_hw *hw,
 	ath_dbg(common, ATH_DBG_CONFIG, "Detach Interface\n");
 
 	mutex_lock(&priv->mutex);
+	if (priv->ah->ah_flags & AH_UNPLUGGED) {
+		ath_dbg(common, ATH_DBG_ANY, "Device not present\n");
+		mutex_unlock(&priv->mutex);
+		return;
+	}
 	ath9k_htc_ps_wakeup(priv);
 
 	memset(&hvif, 0, sizeof(struct ath9k_htc_target_vif));
@@ -1471,11 +1487,17 @@ static void ath9k_htc_configure_filter(struct ieee80211_hw *hw,
 	u32 rfilt;
 
 	mutex_lock(&priv->mutex);
-	ath9k_htc_ps_wakeup(priv);
 
 	changed_flags &= SUPPORTED_FILTERS;
 	*total_flags &= SUPPORTED_FILTERS;
 
+	if (priv->ah->ah_flags & AH_UNPLUGGED) {
+		ath_dbg(ath9k_hw_common(priv->ah), ATH_DBG_ANY,
+			"Device not present\n");
+		mutex_unlock(&priv->mutex);
+		return;
+	}
+	ath9k_htc_ps_wakeup(priv);
 	priv->rxfilter = *total_flags;
 	rfilt = ath9k_htc_calcrxfilter(priv);
 	ath9k_hw_setrxfilter(priv->ah, rfilt);
diff --git a/drivers/net/wireless/ath/ath9k/wmi.c b/drivers/net/wireless/ath/ath9k/wmi.c
index 8f42ea7..8f42d42 100644
--- a/drivers/net/wireless/ath/ath9k/wmi.c
+++ b/drivers/net/wireless/ath/ath9k/wmi.c
@@ -250,7 +250,7 @@ int ath9k_wmi_cmd(struct wmi *wmi, enum wmi_cmd_id cmd_id,
 	int time_left, ret = 0;
 	unsigned long flags;
 
-	if (wmi->drv_priv->op_flags & OP_UNPLUGGED)
+	if (wmi->drv_priv->ah->ah_flags & AH_UNPLUGGED)
 		return 0;
 
 	skb = alloc_skb(headroom + cmd_len, GFP_ATOMIC);
-- 
1.7.3.3

[PATCH 2/2] ath9k_htc: Fix unnecessary warnings on card removal

[Sujith]

Rajkumar Manoharan wrote:
> diff --git a/drivers/net/wireless/ath/ath9k/htc.h b/drivers/net/wireless/ath/ath9k/htc.h
> index fdf9d5f..d90838a 100644
> --- a/drivers/net/wireless/ath/ath9k/htc.h
> +++ b/drivers/net/wireless/ath/ath9k/htc.h
> @@ -339,7 +339,6 @@ void ath_htc_cancel_btcoex_work(struct ath9k_htc_priv *priv);
>  #define OP_ASSOCIATED		   BIT(7)
>  #define OP_ENABLE_BEACON	   BIT(8)
>  #define OP_LED_DEINIT		   BIT(9)
> -#define OP_UNPLUGGED		   BIT(10)
>  #define OP_BT_PRIORITY_DETECTED	   BIT(11)
>  #define OP_BT_SCAN		   BIT(12)

You are leaving a hole here.

> @@ -1231,6 +1236,12 @@ static void ath9k_htc_stop(struct ieee80211_hw *hw)
>  	cancel_delayed_work_sync(&priv->ath9k_led_blink_work);
>  	ath9k_led_stop_brightness(priv);
>  
> +	if (ah->ah_flags & AH_UNPLUGGED) {
> +		ath_dbg(common, ATH_DBG_ANY, "Device not present\n");
> +		mutex_unlock(&priv->mutex);
> +		return;
> +	}
> +

This doesn't take of purging the TX queues in both the driver layer and HIF.
Also, in case of BT combo devices, the workqueue instances aren't canceled.

Instead of adding such checks throughout the driver and increasing code size,
we can just fix the warning to handle the unplugged case. It doesn't matter
if a few extra hardware calls are made, the device is no longer present anyway. :)

Sujith