rt2x00: rt2800lib: fix VGC adjustment for RT3572 and RT3593

The Ralink DPO_RT5572_LinuxSTA_2.6.1.3_20121022
reference driver uses different RSSI threshold
and VGC adjustment values for the RT3572 and
RT3593 chipsets.

Update the rt2800_link_tuner function to use the
same values. Also change the comment in the function
to make it more generic.

References:

  RT35xx_ChipAGCAdjust function in chips/rt35xx.c
  RSSI_FOR_MID_LOW_SENSIBILITY constant in include/chip/rtmp_phy.h
  RT3593_R66_MID_LOW_SENS_GET macro in include/chip/rt3593.h
  RT3593_R66_NON_MID_LOW_SEMS_GET macro in include/chips/rt3593.h

Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
Acked-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c
index be68b04..a114cab 100644 (file)
--- a/drivers/net/wireless/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/rt2x00/rt2800lib.c
@@ -4471,19 +4471,34 @@ void rt2800_link_tuner(struct rt2x00_dev *rt2x00dev, struct link_qual *qual,
 
        if (rt2x00_rt_rev(rt2x00dev, RT2860, REV_RT2860C))
                return;
-       /*
-        * When RSSI is better then -80 increase VGC level with 0x10, except
-        * for rt5592 chip.
+
+       /* When RSSI is better than a certain threshold, increase VGC
+        * with a chip specific value in order to improve the balance
+        * between sensibility and noise isolation.
         */
 
        vgc = rt2800_get_default_vgc(rt2x00dev);
 
-       if (rt2x00_rt(rt2x00dev, RT5592)) {
+       switch (rt2x00dev->chip.rt) {
+       case RT3572:
+       case RT3593:
+               if (qual->rssi > -65) {
+                       if (rt2x00dev->curr_band == IEEE80211_BAND_2GHZ)
+                               vgc += 0x20;
+                       else
+                               vgc += 0x10;
+               }
+               break;
+
+       case RT5592:
                if (qual->rssi > -65)
                        vgc += 0x20;
-       } else {
+               break;
+
+       default:
                if (qual->rssi > -80)
                        vgc += 0x10;
+               break;
        }
 
        rt2800_set_vgc(rt2x00dev, qual, vgc);