Re: [RFC PATCH] rtl8187: Fix led support for rfkill

[Hin-Tak Leung <htl10@users.sourceforge.net>]

Wu Zhangjin wrote:
> led can not be turned off normally when rfkill is blocked, the cause is
> the led_turn_off() function exit as not expected:

Hmm. While this sounds more sensible, is it needed? And what does the windows 
driver do?

I think there are two kind of LEDs - one that comes on and off with the rfkill 
switch; Larry or Herton makes the 2nd one, if there is one, blink while there is 
traffic (and stay steady on otherwise).

> 
> drivers/net/wireless/rtl818x/rtl8187/leds.c:
> 
> static void led_turn_off(struct work_struct *work)
> {
> 	[...]
> 	/* Don't change the LED, when the device is down. */
> 	if (!priv->vif || priv->vif->type == NL80211_IFTYPE_UNSPECIFIED)
> 		return ;
> 	[...]
> 
> When rfkill is blocked, the function calling order looks like this:
> 
> net/mac80211/iface.c:
> 
> ieee80211_do_stop
> 	-> drv_remove_interface = rtl8187_remove_interface
> 	-> ieee80211_stop_device
> 		-> led_set_brightness
> 			-> led_turn_off
> 	-> drv_stop = rtl8187_stop
> 
> rtl8187_remove_interface() set priv->vif to NULL, so, led_turn_off()
> will return and will not be able to turn off the led. delay the setting
> of priv->vif to rtl8187_stop() can solve it.
> 
> Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
> ---
>  drivers/net/wireless/rtl818x/rtl8187/dev.c |    8 ++++----
>  1 files changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/net/wireless/rtl818x/rtl8187/dev.c b/drivers/net/wireless/rtl818x/rtl8187/dev.c
> index 2bb5297..1fea0cd 100644
> --- a/drivers/net/wireless/rtl818x/rtl8187/dev.c
> +++ b/drivers/net/wireless/rtl818x/rtl8187/dev.c
> @@ -1007,6 +1007,9 @@ static void rtl8187_stop(struct ieee80211_hw *dev)
>  	u32 reg;
>  
>  	mutex_lock(&priv->conf_mutex);
> +
> +	priv->vif = NULL;
> +
>  	rtl818x_iowrite16(priv, &priv->map->INT_MASK, 0);
>  
>  	reg = rtl818x_ioread8(priv, &priv->map->CMD);
> @@ -1067,10 +1070,7 @@ exit:
>  static void rtl8187_remove_interface(struct ieee80211_hw *dev,
>  				     struct ieee80211_vif *vif)
>  {
> -	struct rtl8187_priv *priv = dev->priv;
> -	mutex_lock(&priv->conf_mutex);
> -	priv->vif = NULL;
> -	mutex_unlock(&priv->conf_mutex);
> +	/* Nothing to do */
>  }
>  
>  static int rtl8187_config(struct ieee80211_hw *dev, u32 changed)