From 72b55735d2f26b1dfcb206773974c465ca7ef04d Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka Date: Mon, 26 Aug 2013 15:18:53 +0200 Subject: rt2800: fix wrong TX power compensation commit 6e956da2027c767859128b9bfef085cf2a8e233b upstream. We should not do temperature compensation on devices without EXTERNAL_TX_ALC bit set (called DynamicTxAgcControl on vendor driver). Such devices can have totally bogus TSSI parameters on the EEPROM, but still threaded by us as valid and result doing wrong TX power calculations. This fix inability to connect to AP on slightly longer distance on some Ralink chips/devices. Reported-and-tested-by: Fabien ADAM Signed-off-by: Stanislaw Gruszka Signed-off-by: John W. Linville [bwh: Backported to 3.2: use rt2x00_eeprom_read()] Signed-off-by: Ben Hutchings --- drivers/net/wireless/rt2x00/rt2800lib.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers') diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c index 67cbe5a1a928..8fb8c9e75688 100644 --- a/drivers/net/wireless/rt2x00/rt2800lib.c +++ b/drivers/net/wireless/rt2x00/rt2800lib.c @@ -2066,6 +2066,13 @@ static int rt2800_get_gain_calibration_delta(struct rt2x00_dev *rt2x00dev) u8 step; int i; + /* + * First check if temperature compensation is supported. + */ + rt2x00_eeprom_read(rt2x00dev, EEPROM_NIC_CONF1, &eeprom); + if (!rt2x00_get_field16(eeprom, EEPROM_NIC_CONF1_EXTERNAL_TX_ALC)) + return 0; + /* * Read TSSI boundaries for temperature compensation from * the EEPROM. -- cgit v1.2.3