ath9k_common: add new module to share 802.11n driver helpers

ath9k and ath9k_htc share a lot of common hardware characteristics.
They only differ in that ath9k_htc works with a target CPU and ath9k
works directly with the hardware. ath9k_htc will do *some* things in
the firmware, but a lot of others on the host.

The common 802.11n hardware code is already shared through the ath9k_hw
module. Common helpers amongst all Atheros drivers can use the ath module,
this includes ath5k and ar9170 as users. But there is some common driver
specific helpers which are not exactly hardware code which ath9k and
ath9k_htc can share. We'll be using ath9k_common for this to avoid
bloating the ath module and the common 802.11n hardware module ath9k_hw.

We start by sharing skb pre and post processing in preparation for a hand
off to mac80211.

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

1 files changed, 123 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath/ath9k/common.h b/drivers/net/wireless/ath/ath9k/common.h
new file mode 100644
index 00000000000..292e3d860c0
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/common.h
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 2009 Atheros Communications Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <net/mac80211.h>
+
+#include "../ath.h"
+#include "../debug.h"
+
+#include "hw.h"
+
+/* Common header for Atheros 802.11n base driver cores */
+
+#define WME_NUM_TID             16
+#define WME_BA_BMP_SIZE         64
+#define WME_MAX_BA              WME_BA_BMP_SIZE
+#define ATH_TID_MAX_BUFS        (2 * WME_MAX_BA)
+
+#define WME_AC_BE   0
+#define WME_AC_BK   1
+#define WME_AC_VI   2
+#define WME_AC_VO   3
+#define WME_NUM_AC  4
+
+#define ATH_RSSI_DUMMY_MARKER   0x127
+#define ATH_RSSI_LPF_LEN                10
+#define RSSI_LPF_THRESHOLD              -20
+#define ATH_RSSI_EP_MULTIPLIER     (1<<7)
+#define ATH_EP_MUL(x, mul)         ((x) * (mul))
+#define ATH_RSSI_IN(x)             (ATH_EP_MUL((x), ATH_RSSI_EP_MULTIPLIER))
+#define ATH_LPF_RSSI(x, y, len) \
+    ((x != ATH_RSSI_DUMMY_MARKER) ? (((x) * ((len) - 1) + (y)) / (len)) : (y))
+#define ATH_RSSI_LPF(x, y) do {                                         \
+    if ((y) >= RSSI_LPF_THRESHOLD)                                      \
+        x = ATH_LPF_RSSI((x), ATH_RSSI_IN((y)), ATH_RSSI_LPF_LEN);      \
+} while (0)
+#define ATH_EP_RND(x, mul)                                              \
+        ((((x)%(mul)) >= ((mul)/2)) ? ((x) + ((mul) - 1)) / (mul) : (x)/(mul))
+
+struct ath_atx_ac {
+        int sched;
+        int qnum;
+        struct list_head list;
+        struct list_head tid_q;
+};
+
+struct ath_buf_state {
+        int bfs_nframes;
+        u16 bfs_al;
+        u16 bfs_frmlen;
+        int bfs_seqno;
+        int bfs_tidno;
+        int bfs_retries;
+        u8 bf_type;
+        u32 bfs_keyix;
+        enum ath9k_key_type bfs_keytype;
+};
+
+struct ath_buf {
+        struct list_head list;
+        struct ath_buf *bf_lastbf;      /* last buf of this unit (a frame or
+                                           an aggregate) */
+        struct ath_buf *bf_next;        /* next subframe in the aggregate */
+        struct sk_buff *bf_mpdu;        /* enclosing frame structure */
+        struct ath_desc *bf_desc;       /* virtual addr of desc */
+        dma_addr_t bf_daddr;            /* physical addr of desc */
+        dma_addr_t bf_buf_addr;         /* physical addr of data buffer */
+        bool bf_stale;
+        u16 bf_flags;
+        struct ath_buf_state bf_state;
+        dma_addr_t bf_dmacontext;
+};
+
+struct ath_atx_tid {
+        struct list_head list;
+        struct list_head buf_q;
+        struct ath_node *an;
+        struct ath_atx_ac *ac;
+        struct ath_buf *tx_buf[ATH_TID_MAX_BUFS];
+        u16 seq_start;
+        u16 seq_next;
+        u16 baw_size;
+        int tidno;
+        int baw_head;   /* first un-acked tx buffer */
+        int baw_tail;   /* next unused tx buffer slot */
+        int sched;
+        int paused;
+        u8 state;
+};
+
+struct ath_node {
+        struct ath_common *common;
+        struct ath_atx_tid tid[WME_NUM_TID];
+        struct ath_atx_ac ac[WME_NUM_AC];
+        u16 maxampdu;
+        u8 mpdudensity;
+        int last_rssi;
+};
+
+int ath9k_cmn_rx_skb_preprocess(struct ath_common *common,
+                                struct ieee80211_hw *hw,
+                                struct sk_buff *skb,
+                                struct ath_rx_status *rx_stats,
+                                struct ieee80211_rx_status *rx_status,
+                                bool *decrypt_error);
+
+void ath9k_cmn_rx_skb_postprocess(struct ath_common *common,
+                                  struct sk_buff *skb,
+                                  struct ath_rx_status *rx_stats,
+                                  struct ieee80211_rx_status *rxs,
+                                  bool decrypt_error);