From 2a11df6ee58d1b1fc7e5ecd7593a04d7555dc522 Mon Sep 17 00:00:00 2001 From: Wey-Yi Guy Date: Fri, 15 Jan 2010 13:43:38 -0800 Subject: [PATCH] iwlwifi: software w/a for h/w bug cause Rx bit get clear This is a w/a for a hardware bug. the h/w bug may cause the Rx bit (bit 15 before shifting it to 31) to clear when using interrupt coalescing. This does not mean frames are lost - their processing is just delayed until next interrupt arrives. Signed-off-by: Wey-Yi Guy Signed-off-by: Reinette Chatre Signed-off-by: John W. Linville --- drivers/net/wireless/iwlwifi/iwl-core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c index 29eb7b4..9d6c144 100644 --- a/drivers/net/wireless/iwlwifi/iwl-core.c +++ b/drivers/net/wireless/iwlwifi/iwl-core.c @@ -1803,6 +1803,16 @@ irqreturn_t iwl_isr_ict(int irq, void *data) if (val == 0xffffffff) val = 0; + /* + * this is a w/a for a h/w bug. the h/w bug may cause the Rx bit + * (bit 15 before shifting it to 31) to clear when using interrupt + * coalescing. fortunately, bits 18 and 19 stay set when this happens + * so we use them to decide on the real state of the Rx bit. + * In order words, bit 15 is set if bit 18 or bit 19 are set. + */ + if (val & 0xC0000) + val |= 0x8000; + inta = (0xff & val) | ((0xff00 & val) << 16); IWL_DEBUG_ISR(priv, "ISR inta 0x%08x, enabled 0x%08x ict 0x%08x\n", inta, inta_mask, val); -- 2.7.4