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>

1 files changed, 20 insertions, 5 deletions

diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c
index be68b0485833..a114cab413e9 100644
--- 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);