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

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

wu zhangjin wrote:
> On Sun, Mar 27, 2011 at 5:33 AM, Hin-Tak Leung
> <htl10@users.sourceforge.net> wrote:
>> 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).
> 
> I have used this driver on the YeeLoong netbook(only support Linux),
> there is only one LED for rtl8187, when there is traffic, it blinks
> perfectly, but If press the hotkey to turn off the rf, the network
> interface is down, but the LED is still light, then, the users may
> mistakenly think the hotkey or rfkill support doesn't work or simply
> think the interface is still on. So, that's why we may need to fix it.

My laptop (a Toshiba one) has the other kind of LED - the LED only comes on and 
off in relation to the rfkill switch, and does not blink with traffic. I think 
Herton or Larry has some devices with both types.

Hmm, I seem to have the impression that there is code somewhere for switching a 
singular LED's behavior of the driver between one or the other, by echo'ing into 
sysfs or some other trickery? Or would that be a desired approach if that's not 
done at the moment?

> 
> Regards,
> Wu Zhangjin
> 
>>> 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)
>