diff --git a/drivers/net/wireless/rt2x00/rt2800.h b/drivers/net/wireless/rt2x00/rt2800.h index e5c05d8c7448..063bfa8b91f4 100644 --- a/drivers/net/wireless/rt2x00/rt2800.h +++ b/drivers/net/wireless/rt2x00/rt2800.h @@ -2474,6 +2474,12 @@ struct mac_iveiv_entry { */ #define EIRP_MAX_TX_POWER_LIMIT 0x50 +/* + * Number of TBTT intervals after which we have to adjust + * the hw beacon timer. + */ +#define BCN_TBTT_OFFSET 64 + /* * RT2800 driver data structure */ @@ -2484,6 +2490,7 @@ struct rt2800_drv_data { u8 bbp26; u8 txmixer_gain_24g; u8 txmixer_gain_5g; + unsigned int tbtt_tick; }; #endif /* RT2800_H */ diff --git a/drivers/net/wireless/rt2x00/rt2800pci.c b/drivers/net/wireless/rt2x00/rt2800pci.c index 9375db455456..0397bbf0ce01 100644 --- a/drivers/net/wireless/rt2x00/rt2800pci.c +++ b/drivers/net/wireless/rt2x00/rt2800pci.c @@ -809,7 +809,33 @@ static void rt2800pci_pretbtt_tasklet(unsigned long data) static void rt2800pci_tbtt_tasklet(unsigned long data) { struct rt2x00_dev *rt2x00dev = (struct rt2x00_dev *)data; + struct rt2800_drv_data *drv_data = rt2x00dev->drv_data; + u32 reg; + rt2x00lib_beacondone(rt2x00dev); + + if (rt2x00dev->intf_ap_count) { + /* + * The rt2800pci hardware tbtt timer is off by 1us per tbtt + * causing beacon skew and as a result causing problems with + * some powersaving clients over time. Shorten the beacon + * interval every 64 beacons by 64us to mitigate this effect. + */ + if (drv_data->tbtt_tick == (BCN_TBTT_OFFSET - 2)) { + rt2x00pci_register_read(rt2x00dev, BCN_TIME_CFG, ®); + rt2x00_set_field32(®, BCN_TIME_CFG_BEACON_INTERVAL, + (rt2x00dev->beacon_int * 16) - 1); + rt2x00pci_register_write(rt2x00dev, BCN_TIME_CFG, reg); + } else if (drv_data->tbtt_tick == (BCN_TBTT_OFFSET - 1)) { + rt2x00pci_register_read(rt2x00dev, BCN_TIME_CFG, ®); + rt2x00_set_field32(®, BCN_TIME_CFG_BEACON_INTERVAL, + (rt2x00dev->beacon_int * 16)); + rt2x00pci_register_write(rt2x00dev, BCN_TIME_CFG, reg); + } + drv_data->tbtt_tick++; + drv_data->tbtt_tick %= BCN_TBTT_OFFSET; + } + if (test_bit(DEVICE_STATE_ENABLED_RADIO, &rt2x00dev->flags)) rt2800pci_enable_interrupt(rt2x00dev, INT_MASK_CSR_TBTT); }