atheros: define shared bssidmask setting

Also make ath5k and ath9k use it, and share register definitions.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 7 insertions, 114 deletions

diff --git a/drivers/net/wireless/ath/ath5k/pcu.c b/drivers/net/wireless/ath/ath5k/pcu.c
index f03c06d583e6..9ac763875a98 100644
--- a/drivers/net/wireless/ath/ath5k/pcu.c
+++ b/drivers/net/wireless/ath/ath5k/pcu.c
@@ -290,10 +290,10 @@ void ath5k_hw_set_associd(struct ath5k_hw *ah, const u8 *bssid, u16 assoc_id)
 	 */
 	if (ah->ah_version == AR5K_AR5212) {
 		ath5k_hw_reg_write(ah, get_unaligned_le32(common->bssidmask),
-							AR5K_BSS_IDM0);
+				   AR_BSSMSKL);
 		ath5k_hw_reg_write(ah,
 				   get_unaligned_le16(common->curbssid + 4),
-				   AR5K_BSS_IDM1);
+				   AR_BSSMSKU);
 	}
 
 	/*
@@ -301,9 +301,9 @@ void ath5k_hw_set_associd(struct ath5k_hw *ah, const u8 *bssid, u16 assoc_id)
 	 */
 	low_id = get_unaligned_le32(bssid);
 	high_id = get_unaligned_le16(bssid);
-	ath5k_hw_reg_write(ah, low_id, AR5K_BSS_ID0);
+	ath5k_hw_reg_write(ah, low_id, AR_BSSMSKL);
 	ath5k_hw_reg_write(ah, high_id | ((assoc_id & 0x3fff) <<
-				AR5K_BSS_ID1_AID_S), AR5K_BSS_ID1);
+				AR5K_BSS_ID1_AID_S), AR_BSSMSKU);
 
 	if (assoc_id == 0) {
 		ath5k_hw_disable_pspoll(ah);
@@ -316,125 +316,18 @@ void ath5k_hw_set_associd(struct ath5k_hw *ah, const u8 *bssid, u16 assoc_id)
 	ath5k_hw_enable_pspoll(ah, NULL, 0);
 }
 
-/**
- * ath5k_hw_set_bssid_mask - filter out bssids we listen
- *
- * @ah: the &struct ath5k_hw
- * @mask: the bssid_mask, a u8 array of size ETH_ALEN
- *
- * BSSID masking is a method used by AR5212 and newer hardware to inform PCU
- * which bits of the interface's MAC address should be looked at when trying
- * to decide which packets to ACK. In station mode and AP mode with a single
- * BSS every bit matters since we lock to only one BSS. In AP mode with
- * multiple BSSes (virtual interfaces) not every bit matters because hw must
- * accept frames for all BSSes and so we tweak some bits of our mac address
- * in order to have multiple BSSes.
- *
- * NOTE: This is a simple filter and does *not* filter out all
- * relevant frames. Some frames that are not for us might get ACKed from us
- * by PCU because they just match the mask.
- *
- * When handling multiple BSSes you can get the BSSID mask by computing the
- * set of  ~ ( MAC XOR BSSID ) for all bssids we handle.
- *
- * When you do this you are essentially computing the common bits of all your
- * BSSes. Later it is assumed the harware will "and" (&) the BSSID mask with
- * the MAC address to obtain the relevant bits and compare the result with
- * (frame's BSSID & mask) to see if they match.
- */
-/*
- * Simple example: on your card you have have two BSSes you have created with
- * BSSID-01 and BSSID-02. Lets assume BSSID-01 will not use the MAC address.
- * There is another BSSID-03 but you are not part of it. For simplicity's sake,
- * assuming only 4 bits for a mac address and for BSSIDs you can then have:
- *
- *                  \
- * MAC:        0001 |
- * BSSID-01:   0100 | --> Belongs to us
- * BSSID-02:   1001 |
- *                  /
- * -------------------
- * BSSID-03:   0110  | --> External
- * -------------------
- *
- * Our bssid_mask would then be:
- *
- *             On loop iteration for BSSID-01:
- *             ~(0001 ^ 0100)  -> ~(0101)
- *                             ->   1010
- *             bssid_mask      =    1010
- *
- *             On loop iteration for BSSID-02:
- *             bssid_mask &= ~(0001   ^   1001)
- *             bssid_mask =   (1010)  & ~(0001 ^ 1001)
- *             bssid_mask =   (1010)  & ~(1001)
- *             bssid_mask =   (1010)  &  (0110)
- *             bssid_mask =   0010
- *
- * A bssid_mask of 0010 means "only pay attention to the second least
- * significant bit". This is because its the only bit common
- * amongst the MAC and all BSSIDs we support. To findout what the real
- * common bit is we can simply "&" the bssid_mask now with any BSSID we have
- * or our MAC address (we assume the hardware uses the MAC address).
- *
- * Now, suppose there's an incoming frame for BSSID-03:
- *
- * IFRAME-01:  0110
- *
- * An easy eye-inspeciton of this already should tell you that this frame
- * will not pass our check. This is beacuse the bssid_mask tells the
- * hardware to only look at the second least significant bit and the
- * common bit amongst the MAC and BSSIDs is 0, this frame has the 2nd LSB
- * as 1, which does not match 0.
- *
- * So with IFRAME-01 we *assume* the hardware will do:
- *
- *     allow = (IFRAME-01 & bssid_mask) == (bssid_mask & MAC) ? 1 : 0;
- *  --> allow = (0110 & 0010) == (0010 & 0001) ? 1 : 0;
- *  --> allow = (0010) == 0000 ? 1 : 0;
- *  --> allow = 0
- *
- *  Lets now test a frame that should work:
- *
- * IFRAME-02:  0001 (we should allow)
- *
- *     allow = (0001 & 1010) == 1010
- *
- *     allow = (IFRAME-02 & bssid_mask) == (bssid_mask & MAC) ? 1 : 0;
- *  --> allow = (0001 & 0010) ==  (0010 & 0001) ? 1 :0;
- *  --> allow = (0010) == (0010)
- *  --> allow = 1
- *
- * Other examples:
- *
- * IFRAME-03:  0100 --> allowed
- * IFRAME-04:  1001 --> allowed
- * IFRAME-05:  1101 --> allowed but its not for us!!!
- *
- */
-int ath5k_hw_set_bssid_mask(struct ath5k_hw *ah, const u8 *mask)
+void ath5k_hw_set_bssid_mask(struct ath5k_hw *ah, const u8 *mask)
 {
 	struct ath_common *common = ath5k_hw_common(ah);
-	u32 low_id, high_id;
 	ATH5K_TRACE(ah->ah_sc);
 
 	/* Cache bssid mask so that we can restore it
 	 * on reset */
 	memcpy(common->bssidmask, mask, ETH_ALEN);
-	if (ah->ah_version == AR5K_AR5212) {
-		low_id = get_unaligned_le32(mask);
-		high_id = get_unaligned_le16(mask + 4);
-
-		ath5k_hw_reg_write(ah, low_id, AR5K_BSS_IDM0);
-		ath5k_hw_reg_write(ah, high_id, AR5K_BSS_IDM1);
-
-		return 0;
-	}
-
-	return -EIO;
+	if (ah->ah_version == AR5K_AR5212)
+		ath_hw_setbssidmask(common);
 }
 
-
 /************\
 * RX Control *
 \************/