ath9k: fix two more bugs in tx power

commit 21fdc87248d1d28492c775e05fa92b3c8c7bc8db upstream.

This is the same fix as

   commit 841051602e3fa18ea468fe5a177aa92b6eb44b56
   Author: Matteo Croce <technoboy85@gmail.com>
   Date:   Fri Dec 3 02:25:08 2010 +0100

   The ath9k driver subtracts 3 dBm to the txpower as with two radios the
   signal power is doubled.
   The resulting value is assigned in an u16 which overflows and makes
   the card work at full power.

in two more places. I grepped the ath tree and didn't find any others.

Signed-off-by: Daniel Halperin <dhalperi@cs.washington.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
index 37af3f4..db4416c 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
@@ -4598,10 +4598,16 @@ static void ar9003_hw_set_power_per_rate_table(struct ath_hw *ah,
        case 1:
                break;
        case 2:
-               scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+               if (scaledPower > REDUCE_SCALED_POWER_BY_TWO_CHAIN)
+                       scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+               else
+                       scaledPower = 0;
                break;
        case 3:
-               scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+               if (scaledPower > REDUCE_SCALED_POWER_BY_THREE_CHAIN)
+                       scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+               else
+                       scaledPower = 0;
                break;
        }
 

diff --git a/drivers/net/wireless/ath/ath9k/eeprom_9287.c b/drivers/net/wireless/ath/ath9k/eeprom_9287.c
index 8cd8333..945e448 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/eeprom_9287.c
+++ b/drivers/net/wireless/ath/ath9k/eeprom_9287.c
@@ -522,10 +522,16 @@ static void ath9k_hw_set_ar9287_power_per_rate_table(struct ath_hw *ah,
        case 1:
                break;
        case 2:
-               scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+               if (scaledPower > REDUCE_SCALED_POWER_BY_TWO_CHAIN)
+                       scaledPower -= REDUCE_SCALED_POWER_BY_TWO_CHAIN;
+               else
+                       scaledPower = 0;
                break;
        case 3:
-               scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+               if (scaledPower > REDUCE_SCALED_POWER_BY_THREE_CHAIN)
+                       scaledPower -= REDUCE_SCALED_POWER_BY_THREE_CHAIN;
+               else
+                       scaledPower = 0;
                break;
        }
        scaledPower = max((u16)0, scaledPower);