Am Montag, den 25.04.2016, 17:53 +0200 schrieb Michael Büsch:

On Mon, 25 Apr 2016 09:40:51 +0200
Lucas Stach [off-list ref] wrote:

quoted

On my system the SPROM correctly defines the only wired LED (radio)
but
skips all others, leading to the hardcode to register LEDs with RX
and TX
triggers.

Hm ok. It probably is a good idea to change the condition from

if (sprom[led_index] == 0xFF)

to

if ((sprom[0] & sprom[1] & sprom[2] & sprom[3]) == 0xFF)

So the hardcoding only happens if there is no LED configured in the
SPROM. (I think my card does this (see below), but I can check that
later)

quoted

These triggers cause many uneccesary CPU wakeups to drive LEDs
that aren't even present in the system, reducing battery runtime.

Numbers please. Did you measure that is actually causes more
_wakeups_?
How many?
The led work is placed in the mac80211 workqueue and LED updates only
happen on behalf of mac80211 activities (by default). It only causes
additional wakeups, if there's nothing else scheduled on the
workqueue
anyways (which might well be the case. So we need numbers. :)

The blinking LEDs use a timer to enforce a constant blink rate at a
50ms on/off interval. While they are only triggered if there is some
RX/TX activity in the system, they cause up to 20 wakeups/second/led.
As the timers used for LED activity aren't deferrable, this hardcode is
causing 40 unnecessary CPU wakeups/s in my system.

quoted

Remove the hardcode to stop it from doing any harm. If this code is
useful
for others it should probably be reworked as a quirk table
triggering only
for individual systems that need it.

There are cards that need it. I don't know how many that are, but I
own
an older 4306 PC-Card card that needs this.

So this effectively is a regression for this card.

So I don't think this is acceptable.
You should at least make this configurable via module parameter or
such.
Or maybe the change from above already is enough. It should work for
your case.

There are some people that find those kinds of blinking LEDs
distracting, so a module parameter to disable them altogether might be
a good thing to have. Causing CPU wakeups in a system where those LEDs
aren't even physically populated is clearly undesired behavior.

If checking that the SPROM doesn't define any LED behavior is enough to
not regress your use case, I would be glad to rework the patch
accordingly.

Regards,
Lucas

quoted

Signed-off-by: Lucas Stach <dev@lynxeye.de>
---
 drivers/net/wireless/broadcom/b43/leds.c | 26 ++----------------
--------
 1 file changed, 2 insertions(+), 24 deletions(-)

diff --git a/drivers/net/wireless/broadcom/b43/leds.c

b/drivers/net/wireless/broadcom/b43/leds.c
index d79ab2a..77d2dad 100644

--- a/drivers/net/wireless/broadcom/b43/leds.c
+++ b/drivers/net/wireless/broadcom/b43/leds.c

@@ -224,31 +224,9 @@ static void b43_led_get_sprominfo(struct

b43_wldev *dev,
 
 	if (sprom[led_index] == 0xFF) {
 		/* There is no LED information in the SPROM
-		 * for this LED. Hardcode it here. */
+		 * for this LED. Keep it disabled. */
 		*activelow = false;
-		switch (led_index) {
-		case 0:
-			*behaviour = B43_LED_ACTIVITY;
-			*activelow = true;
-			if (dev->dev->board_vendor ==
PCI_VENDOR_ID_COMPAQ)
-				*behaviour = B43_LED_RADIO_ALL;
-			break;
-		case 1:
-			*behaviour = B43_LED_RADIO_B;
-			if (dev->dev->board_vendor ==
PCI_VENDOR_ID_ASUSTEK)
-				*behaviour = B43_LED_ASSOC;
-			break;
-		case 2:
-			*behaviour = B43_LED_RADIO_A;
-			break;
-		case 3:
-			*behaviour = B43_LED_OFF;
-			break;
-		default:
-			*behaviour = B43_LED_OFF;
-			B43_WARN_ON(1);
-			return;
-		}
+		*behaviour = B43_LED_OFF;
 	} else {
 		*behaviour = sprom[led_index] & B43_LED_BEHAVIOUR;
 		*activelow = !!(sprom[led_index] &
B43_LED_ACTIVELOW);