Re: [PATCH/RFC] ath9k: fix two more bugs in tx power
From: Mohammed Shafi <hidden>
Date: 2011-05-27 07:18:46
On Thu, May 26, 2011 at 10:13 PM, Daniel Halperin [off-list ref] wrote:
quoted hunk ↗ jump to hunk
This is the same fix as commit 841051602e3fa18ea468fe5a177aa92b6eb44b56 Author: Matteo Croce [off-list ref] 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. Cc: stable@kernel.org Signed-off-by: Daniel Halperin <redacted> --- RFC: Blaise Gassend actually pointed these two bugs out on 12/7/2010 but no one fixed. There was some discussion about refactoring/improving this code, but it never seemed to get anywhere. See this thread: http://comments.gmane.org/gmane.linux.drivers.ath9k.devel/4601 --- drivers/net/wireless/ath/ath9k/ar9003_eeprom.c | 10 ++++++++-- drivers/net/wireless/ath/ath9k/eeprom_9287.c | 10 ++++++++-- 2 files changed, 16 insertions(+), 4 deletions(-)diff --git a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c index 729534c..934e419 100644 --- a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c +++ b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c@@ -4645,10 +4645,16 @@ 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;
should we make the scaledPower as '0' lets have the first check if it
fails, let us retain the scaledPower obtained by
scaledPower = min(powerLimit, maxRegAllowedPower);
am I missing something ?
making scaledPower affects this
minCtlPower = (u8)min(twiceMaxEdgePower, scaledPower);
which in turn affects
pPwrArray[i] =
(u8)min((u16)pPwrArray[i],
minCtlPower);
which in turn affects target Power values
quoted hunk ↗ jump to hunk
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 7856f0d..343fc9f 100644 --- a/drivers/net/wireless/ath/ath9k/eeprom_9287.c +++ b/drivers/net/wireless/ath/ath9k/eeprom_9287.c@@ -524,10 +524,16 @@ 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); -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
-- shafi