From 7fc417556473f15efac269523c17eb92103c6484 Mon Sep 17 00:00:00 2001 From: Luigi Tarenga Date: Tue, 31 Jan 2012 18:51:23 +0100 Subject: [PATCH] rt2800lib: fix wrong -128dBm when signal is stronger than -12dBm This patch correct the type of variables containing the rssi values read from the rxwi. In function rt2800_agc_to_rssi() 3 variables (rssi0, rssi1, rss2) defined as int was assigned a 16bit signed values as unsigned. From a test with a hi-gain antenna I verified that the rxwi contains signed rssi values in the range -13/+81 (inclusive) with 0 as an error condition. In case of negative values a condition is triggered and the function return -128dBm while the signal is at its maximum. This patch correct the cast so negative values are not treated as very high positive values (ex. -13 does not become 243). Signed-off-by: Luigi Tarenga Reviewed-by: Stanislaw Gruszka Signed-off-by: John W. Linville --- drivers/net/wireless/rt2x00/rt2800lib.c | 8 ++++---- 1 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c index 22a1a8f..7bef66d 100644 --- a/drivers/net/wireless/rt2x00/rt2800lib.c +++ b/drivers/net/wireless/rt2x00/rt2800lib.c @@ -514,9 +514,9 @@ EXPORT_SYMBOL_GPL(rt2800_write_tx_data); static int rt2800_agc_to_rssi(struct rt2x00_dev *rt2x00dev, u32 rxwi_w2) { - int rssi0 = rt2x00_get_field32(rxwi_w2, RXWI_W2_RSSI0); - int rssi1 = rt2x00_get_field32(rxwi_w2, RXWI_W2_RSSI1); - int rssi2 = rt2x00_get_field32(rxwi_w2, RXWI_W2_RSSI2); + s8 rssi0 = rt2x00_get_field32(rxwi_w2, RXWI_W2_RSSI0); + s8 rssi1 = rt2x00_get_field32(rxwi_w2, RXWI_W2_RSSI1); + s8 rssi2 = rt2x00_get_field32(rxwi_w2, RXWI_W2_RSSI2); u16 eeprom; u8 offset0; u8 offset1; @@ -552,7 +552,7 @@ static int rt2800_agc_to_rssi(struct rt2x00_dev *rt2x00dev, u32 rxwi_w2) * which gives less energy... */ rssi0 = max(rssi0, rssi1); - return max(rssi0, rssi2); + return (int)max(rssi0, rssi2); } void rt2800_process_rxwi(struct queue_entry *entry, -- 1.7.4.4