staging: wfx: allow to send 802.11 frames

Three things make this task more complex than it should:
  - Chip necessitate to associate a link-id to each station. It is same
    thing than association ID but, using 8 bits only.
  - Rate policy is sent separately from Tx frames
  - Driver try to handle itself power saving of stations and multicast
    data
Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>
Link: https://lore.kernel.org/r/20190919142527.31797-17-Jerome.Pouiller@silabs.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/wfx/Makefile

@@ -9,6 +9,9 @@ wfx-y := \
 	fwio.o \
 	hif_tx.o \
 	hif_rx.o \
+	queue.o \
+	data_tx.o \
+	sta.o \
 	main.o \
 	sta.o \
 	debug.o

drivers/staging/wfx/bh.c

@@ -220,6 +220,8 @@ static int bh_work_tx(struct wfx_dev *wdev, int max_msg)
 			if (try_wait_for_completion(&wdev->hif_cmd.ready)) {
 				WARN(!mutex_is_locked(&wdev->hif_cmd.lock), "data locking error");
 				hif = wdev->hif_cmd.buf_send;
+			} else {
+				hif = wfx_tx_queues_get(wdev);
 			}
 		}
 		if (!hif)

drivers/staging/wfx/data_tx.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Datapath implementation.
+ *
+ * Copyright (c) 2017-2019, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#ifndef WFX_DATA_TX_H
+#define WFX_DATA_TX_H
+
+#include <linux/list.h>
+#include <net/mac80211.h>
+
+#include "hif_api_cmd.h"
+#include "hif_api_mib.h"
+
+// FIXME: use IEEE80211_NUM_TIDS
+#define WFX_MAX_TID               8
+
+struct wfx_tx_priv;
+struct wfx_dev;
+struct wfx_vif;
+
+enum wfx_link_status {
+	WFX_LINK_OFF,
+	WFX_LINK_RESERVE,
+	WFX_LINK_SOFT,
+	WFX_LINK_HARD,
+};
+
+struct wfx_link_entry {
+	unsigned long		timestamp;
+	enum wfx_link_status	status;
+	uint8_t			mac[ETH_ALEN];
+	uint8_t			old_mac[ETH_ALEN];
+	uint8_t			buffered[WFX_MAX_TID];
+	struct sk_buff_head	rx_queue;
+};
+
+struct tx_policy {
+	struct list_head link;
+	uint8_t rates[12];
+	uint8_t usage_count;
+	uint8_t uploaded;
+};
+
+struct tx_policy_cache {
+	struct tx_policy cache[HIF_MIB_NUM_TX_RATE_RETRY_POLICIES];
+	// FIXME: use a trees and drop hash from tx_policy
+	struct list_head used;
+	struct list_head free;
+	spinlock_t lock;
+};
+
+struct wfx_tx_priv {
+	ktime_t xmit_timestamp;
+	struct ieee80211_key_conf *hw_key;
+	uint8_t link_id;
+	uint8_t raw_link_id;
+	uint8_t tid;
+} __packed;
+
+void tx_policy_init(struct wfx_vif *wvif);
+
+void wfx_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control,
+	    struct sk_buff *skb);
+void wfx_tx_confirm_cb(struct wfx_vif *wvif, struct hif_cnf_tx *arg);
+void wfx_skb_dtor(struct wfx_dev *wdev, struct sk_buff *skb);
+
+int wfx_unmap_link(struct wfx_vif *wvif, int link_id);
+void wfx_link_id_work(struct work_struct *work);
+void wfx_link_id_gc_work(struct work_struct *work);
+int wfx_find_link_id(struct wfx_vif *wvif, const u8 *mac);
+
+static inline struct wfx_tx_priv *wfx_skb_tx_priv(struct sk_buff *skb)
+{
+	struct ieee80211_tx_info *tx_info;
+
+	if (!skb)
+		return NULL;
+	tx_info = IEEE80211_SKB_CB(skb);
+	return (struct wfx_tx_priv *) tx_info->rate_driver_data;
+}
+
+static inline struct hif_req_tx *wfx_skb_txreq(struct sk_buff *skb)
+{
+	struct hif_msg *hif = (struct hif_msg *) skb->data;
+	struct hif_req_tx *req = (struct hif_req_tx *) hif->body;
+
+	return req;
+}
+
+#endif /* WFX_DATA_TX_H */

drivers/staging/wfx/hif_rx.c

@@ -53,6 +53,39 @@ static int hif_generic_confirm(struct wfx_dev *wdev, struct hif_msg *hif, void *
 	return status;
 }
 
+static int hif_tx_confirm(struct wfx_dev *wdev, struct hif_msg *hif, void *buf)
+{
+	struct hif_cnf_tx *body = buf;
+	struct wfx_vif *wvif = wdev_to_wvif(wdev, hif->interface);
+
+	WARN_ON(!wvif);
+	if (!wvif)
+		return -EFAULT;
+
+	wfx_tx_confirm_cb(wvif, body);
+	return 0;
+}
+
+static int hif_multi_tx_confirm(struct wfx_dev *wdev, struct hif_msg *hif, void *buf)
+{
+	struct hif_cnf_multi_transmit *body = buf;
+	struct hif_cnf_tx *buf_loc = (struct hif_cnf_tx *) &body->tx_conf_payload;
+	struct wfx_vif *wvif = wdev_to_wvif(wdev, hif->interface);
+	int count = body->num_tx_confs;
+	int i;
+
+	WARN(count <= 0, "corrupted message");
+	WARN_ON(!wvif);
+	if (!wvif)
+		return -EFAULT;
+
+	for (i = 0; i < count; ++i) {
+		wfx_tx_confirm_cb(wvif, buf_loc);
+		buf_loc++;
+	}
+	return 0;
+}
+
 static int hif_startup_indication(struct wfx_dev *wdev, struct hif_msg *hif, void *buf)
 {
 	struct hif_ind_startup *body = buf;
@@ -174,6 +207,10 @@ static const struct {
 	int msg_id;
 	int (*handler)(struct wfx_dev *wdev, struct hif_msg *hif, void *buf);
 } hif_handlers[] = {
+	/* Confirmations */
+	{ HIF_CNF_ID_TX,                   hif_tx_confirm },
+	{ HIF_CNF_ID_MULTI_TRANSMIT,       hif_multi_tx_confirm },
+	/* Indications */
 	{ HIF_IND_ID_STARTUP,              hif_startup_indication },
 	{ HIF_IND_ID_WAKEUP,               hif_wakeup_indication },
 	{ HIF_IND_ID_JOIN_COMPLETE,        hif_join_complete_indication },

drivers/staging/wfx/hif_tx.c

@@ -88,6 +88,7 @@ int wfx_cmd_send(struct wfx_dev *wdev, struct hif_msg *request, void *reply, siz
 	}
 	if (!ret) {
 		dev_err(wdev->dev, "chip did not answer\n");
+		wfx_pending_dump_old_frames(wdev, 3000);
 		wdev->chip_frozen = 1;
 		reinit_completion(&wdev->hif_cmd.done);
 		ret = -ETIMEDOUT;

drivers/staging/wfx/main.c

@@ -28,6 +28,7 @@
 #include "bh.h"
 #include "sta.h"
 #include "debug.h"
+#include "data_tx.h"
 #include "secure_link.h"
 #include "hif_tx_mib.h"
 #include "hif_api_cmd.h"
@@ -53,6 +54,7 @@ static const struct ieee80211_ops wfx_ops = {
 	.stop			= wfx_stop,
 	.add_interface		= wfx_add_interface,
 	.remove_interface	= wfx_remove_interface,
+	.tx			= wfx_tx,
 };
 
 bool wfx_api_older_than(struct wfx_dev *wdev, int major, int minor)
@@ -215,6 +217,7 @@ struct wfx_dev *wfx_init_common(struct device *dev,
 	mutex_init(&wdev->rx_stats_lock);
 	init_completion(&wdev->firmware_ready);
 	wfx_init_hif_cmd(&wdev->hif_cmd);
+	wfx_tx_queues_init(wdev);
 
 	return wdev;
 }
@@ -222,6 +225,7 @@ struct wfx_dev *wfx_init_common(struct device *dev,
 void wfx_free_common(struct wfx_dev *wdev)
 {
 	mutex_destroy(&wdev->rx_stats_lock);
+	wfx_tx_queues_deinit(wdev);
 	ieee80211_free_hw(wdev->hw);
 }
 

drivers/staging/wfx/queue.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * O(1) TX queue with built-in allocator.
+ *
+ * Copyright (c) 2017-2018, Silicon Laboratories, Inc.
+ * Copyright (c) 2010, ST-Ericsson
+ */
+#ifndef WFX_QUEUE_H
+#define WFX_QUEUE_H
+
+#include <linux/skbuff.h>
+
+#include "hif_api_cmd.h"
+
+#define WFX_MAX_STA_IN_AP_MODE    14
+#define WFX_LINK_ID_AFTER_DTIM    (WFX_MAX_STA_IN_AP_MODE + 1)
+#define WFX_LINK_ID_UAPSD         (WFX_MAX_STA_IN_AP_MODE + 2)
+#define WFX_LINK_ID_MAX           (WFX_MAX_STA_IN_AP_MODE + 3)
+
+struct wfx_dev;
+struct wfx_vif;
+
+struct wfx_queue {
+	struct sk_buff_head	queue;
+	int			tx_locked_cnt;
+	int			link_map_cache[WFX_LINK_ID_MAX];
+	u8			queue_id;
+};
+
+struct wfx_queue_stats {
+	int			link_map_cache[WFX_LINK_ID_MAX];
+	struct sk_buff_head	pending;
+	wait_queue_head_t	wait_link_id_empty;
+};
+
+void wfx_tx_lock(struct wfx_dev *wdev);
+void wfx_tx_unlock(struct wfx_dev *wdev);
+void wfx_tx_flush(struct wfx_dev *wdev);
+void wfx_tx_lock_flush(struct wfx_dev *wdev);
+
+void wfx_tx_queues_init(struct wfx_dev *wdev);
+void wfx_tx_queues_deinit(struct wfx_dev *wdev);
+void wfx_tx_queues_lock(struct wfx_dev *wdev);
+void wfx_tx_queues_unlock(struct wfx_dev *wdev);
+void wfx_tx_queues_clear(struct wfx_dev *wdev);
+bool wfx_tx_queues_is_empty(struct wfx_dev *wdev);
+void wfx_tx_queues_wait_empty_vif(struct wfx_vif *wvif);
+struct hif_msg *wfx_tx_queues_get(struct wfx_dev *wdev);
+
+void wfx_tx_queue_put(struct wfx_dev *wdev, struct wfx_queue *queue, struct sk_buff *skb);
+size_t wfx_tx_queue_get_num_queued(struct wfx_queue *queue, u32 link_id_map);
+
+struct sk_buff *wfx_pending_get(struct wfx_dev *wdev, u32 packet_id);
+int wfx_pending_remove(struct wfx_dev *wdev, struct sk_buff *skb);
+int wfx_pending_requeue(struct wfx_dev *wdev, struct sk_buff *skb);
+unsigned int wfx_pending_get_pkt_us_delay(struct wfx_dev *wdev, struct sk_buff *skb);
+void wfx_pending_dump_old_frames(struct wfx_dev *wdev, unsigned int limit_ms);
+
+#endif /* WFX_QUEUE_H */

drivers/staging/wfx/sta.c

@@ -10,11 +10,123 @@
 #include "sta.h"
 #include "wfx.h"
 
+#define TXOP_UNIT 32
+
+static int wfx_set_tim_impl(struct wfx_vif *wvif, bool aid0_bit_set)
+{
+	struct sk_buff *skb;
+	struct hif_ie_flags target_frame = {
+		.beacon = 1,
+	};
+	u16 tim_offset, tim_length;
+	u8 *tim_ptr;
+
+	skb = ieee80211_beacon_get_tim(wvif->wdev->hw, wvif->vif,
+				       &tim_offset, &tim_length);
+	if (!skb)
+		return -ENOENT;
+	tim_ptr = skb->data + tim_offset;
+
+	if (tim_offset && tim_length >= 6) {
+		/* Ignore DTIM count from mac80211:
+		 * firmware handles DTIM internally.
+		 */
+		tim_ptr[2] = 0;
+
+		/* Set/reset aid0 bit */
+		if (aid0_bit_set)
+			tim_ptr[4] |= 1;
+		else
+			tim_ptr[4] &= ~1;
+	}
+
+	hif_update_ie(wvif, &target_frame, tim_ptr, tim_length);
+	dev_kfree_skb(skb);
+
+	return 0;
+}
+
+static void wfx_mcast_start_work(struct work_struct *work)
+{
+	struct wfx_vif *wvif = container_of(work, struct wfx_vif, mcast_start_work);
+
+	cancel_work_sync(&wvif->mcast_stop_work);
+	if (!wvif->aid0_bit_set) {
+		wfx_tx_lock_flush(wvif->wdev);
+		wfx_set_tim_impl(wvif, true);
+		wvif->aid0_bit_set = true;
+		mod_timer(&wvif->mcast_timeout, TU_TO_JIFFIES(1000));
+		wfx_tx_unlock(wvif->wdev);
+	}
+}
+
+static void wfx_mcast_stop_work(struct work_struct *work)
+{
+	struct wfx_vif *wvif = container_of(work, struct wfx_vif, mcast_stop_work);
+
+	if (wvif->aid0_bit_set) {
+		del_timer_sync(&wvif->mcast_timeout);
+		wfx_tx_lock_flush(wvif->wdev);
+		wvif->aid0_bit_set = false;
+		wfx_set_tim_impl(wvif, false);
+		wfx_tx_unlock(wvif->wdev);
+	}
+}
+
+static void wfx_mcast_timeout(struct timer_list *t)
+{
+	struct wfx_vif *wvif = from_timer(wvif, t, mcast_timeout);
+
+	dev_warn(wvif->wdev->dev, "multicast delivery timeout\n");
+	spin_lock_bh(&wvif->ps_state_lock);
+	wvif->mcast_tx = wvif->aid0_bit_set && wvif->mcast_buffered;
+	if (wvif->mcast_tx)
+		wfx_bh_request_tx(wvif->wdev);
+	spin_unlock_bh(&wvif->ps_state_lock);
+}
+
 int wfx_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 {
 	int i;
 	struct wfx_dev *wdev = hw->priv;
 	struct wfx_vif *wvif = (struct wfx_vif *) vif->drv_priv;
+	// FIXME: parameters are set by kernel juste after interface_add.
+	// Keep struct hif_req_edca_queue_params blank?
+	struct hif_req_edca_queue_params default_edca_params[] = {
+		[IEEE80211_AC_VO] = {
+			.queue_id = HIF_QUEUE_ID_VOICE,
+			.aifsn = 2,
+			.cw_min = 3,
+			.cw_max = 7,
+			.tx_op_limit = TXOP_UNIT * 47,
+		},
+		[IEEE80211_AC_VI] = {
+			.queue_id = HIF_QUEUE_ID_VIDEO,
+			.aifsn = 2,
+			.cw_min = 7,
+			.cw_max = 15,
+			.tx_op_limit = TXOP_UNIT * 94,
+		},
+		[IEEE80211_AC_BE] = {
+			.queue_id = HIF_QUEUE_ID_BESTEFFORT,
+			.aifsn = 3,
+			.cw_min = 15,
+			.cw_max = 1023,
+			.tx_op_limit = TXOP_UNIT * 0,
+		},
+		[IEEE80211_AC_BK] = {
+			.queue_id = HIF_QUEUE_ID_BACKGROUND,
+			.aifsn = 7,
+			.cw_min = 15,
+			.cw_max = 1023,
+			.tx_op_limit = TXOP_UNIT * 0,
+		},
+	};
+
+	if (wfx_api_older_than(wdev, 2, 0)) {
+		default_edca_params[IEEE80211_AC_BE].queue_id = HIF_QUEUE_ID_BACKGROUND;
+		default_edca_params[IEEE80211_AC_BK].queue_id = HIF_QUEUE_ID_BESTEFFORT;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(wdev->vif); i++) {
 		if (!wdev->vif[i]) {
@@ -28,12 +140,29 @@ int wfx_add_interface(struct ieee80211_hw *hw, struct ieee80211_vif *vif)
 	wvif->vif = vif;
 	wvif->wdev = wdev;
 
+	INIT_WORK(&wvif->link_id_work, wfx_link_id_work);
+	INIT_DELAYED_WORK(&wvif->link_id_gc_work, wfx_link_id_gc_work);
+
+	spin_lock_init(&wvif->ps_state_lock);
+
+	INIT_WORK(&wvif->mcast_start_work, wfx_mcast_start_work);
+	INIT_WORK(&wvif->mcast_stop_work, wfx_mcast_stop_work);
+	timer_setup(&wvif->mcast_timeout, wfx_mcast_timeout, 0);
+	BUG_ON(ARRAY_SIZE(default_edca_params) != ARRAY_SIZE(wvif->edca.params));
+	for (i = 0; i < IEEE80211_NUM_ACS; i++)
+		memcpy(&wvif->edca.params[i], &default_edca_params[i], sizeof(default_edca_params[i]));
+	tx_policy_init(wvif);
 	return 0;
 }
 
 void wfx_remove_interface(struct ieee80211_hw *hw,
 			  struct ieee80211_vif *vif)
 {
+	struct wfx_vif *wvif = (struct wfx_vif *) vif->drv_priv;
+
+	wfx_tx_queues_wait_empty_vif(wvif);
+	cancel_delayed_work_sync(&wvif->link_id_gc_work);
+	del_timer_sync(&wvif->mcast_timeout);
 }
 
 int wfx_start(struct ieee80211_hw *hw)
@@ -43,4 +172,10 @@ int wfx_start(struct ieee80211_hw *hw)
 
 void wfx_stop(struct ieee80211_hw *hw)
 {
+	struct wfx_dev *wdev = hw->priv;
+
+	wfx_tx_lock_flush(wdev);
+	wfx_tx_queues_clear(wdev);
+	wfx_tx_unlock(wdev);
+	WARN(atomic_read(&wdev->tx_lock), "tx_lock is locked");
 }

drivers/staging/wfx/sta.h

@@ -10,6 +10,14 @@
 
 #include <net/mac80211.h>
 
+#include "hif_api_cmd.h"
+
+struct wfx_edca_params {
+	/* NOTE: index is a linux queue id. */
+	struct hif_req_edca_queue_params params[IEEE80211_NUM_ACS];
+	bool uapsd_enable[IEEE80211_NUM_ACS];
+};
+
 struct wfx_sta_priv {
 	int link_id;
 	int vif_id;

drivers/staging/wfx/traces.h

@@ -12,6 +12,7 @@
 #define _WFX_TRACE_H
 
 #include <linux/tracepoint.h>
+#include <net/mac80211.h>
 
 #include "bus.h"
 #include "hif_api_cmd.h"
@@ -349,6 +350,79 @@ TRACE_EVENT(bh_stats,
 );
 #define _trace_bh_stats(ind, req, cnf, busy, release) trace_bh_stats(ind, req, cnf, busy, release)
 
+TRACE_EVENT(tx_stats,
+	TP_PROTO(struct hif_cnf_tx *tx_cnf, struct sk_buff *skb, int delay),
+	TP_ARGS(tx_cnf, skb, delay),
+	TP_STRUCT__entry(
+		__field(int, pkt_id)
+		__field(int, delay_media)
+		__field(int, delay_queue)
+		__field(int, delay_fw)
+		__field(int, ack_failures)
+		__field(int, flags)
+		__array(int, rate, 4)
+		__array(int, tx_count, 4)
+	),
+	TP_fast_assign(
+		// Keep sync with wfx_rates definition in main.c
+		static const int hw_rate[] = { 0, 1, 2, 3, 6, 7, 8, 9, 10, 11, 12, 13 };
+		struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
+		struct ieee80211_tx_rate *rates = tx_info->driver_rates;
+		int i;
+
+		__entry->pkt_id = tx_cnf->packet_id;
+		__entry->delay_media = tx_cnf->media_delay;
+		__entry->delay_queue = tx_cnf->tx_queue_delay;
+		__entry->delay_fw = delay;
+		__entry->ack_failures = tx_cnf->ack_failures;
+		if (!tx_cnf->status || __entry->ack_failures)
+			__entry->ack_failures += 1;
+
+		for (i = 0; i < IEEE80211_NUM_ACS; i++) {
+			if (rates[0].flags & IEEE80211_TX_RC_MCS)
+				__entry->rate[i] = rates[i].idx;
+			else
+				__entry->rate[i] = hw_rate[rates[i].idx];
+			__entry->tx_count[i] = rates[i].count;
+		}
+		__entry->flags = 0;
+		if (rates[0].flags & IEEE80211_TX_RC_MCS)
+			__entry->flags |= 0x01;
+		if (rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
+			__entry->flags |= 0x02;
+		if (rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
+			__entry->flags |= 0x04;
+		if (rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
+			__entry->flags |= 0x08;
+		if (tx_info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM)
+			__entry->flags |= 0x10;
+		if (tx_cnf->status)
+			__entry->flags |= 0x20;
+		if (tx_cnf->status == HIF_REQUEUE)
+			__entry->flags |= 0x40;
+	),
+	TP_printk("packet ID: %08x, rate policy: %s %d|%d %d|%d %d|%d %d|%d -> %d attempt, Delays media/queue/total: %4dus/%4dus/%4dus",
+		__entry->pkt_id,
+		__print_flags(__entry->flags, NULL,
+			{ 0x01, "M" }, { 0x02, "S" }, { 0x04, "G" },
+			{ 0x08, "R" }, { 0x10, "D" }, { 0x20, "F" },
+			{ 0x40, "Q" }),
+		__entry->rate[0],
+		__entry->tx_count[0],
+		__entry->rate[1],
+		__entry->tx_count[1],
+		__entry->rate[2],
+		__entry->tx_count[2],
+		__entry->rate[3],
+		__entry->tx_count[3],
+		__entry->ack_failures,
+		__entry->delay_media,
+		__entry->delay_queue,
+		__entry->delay_fw
+	)
+);
+#define _trace_tx_stats(tx_cnf, skb, delay) trace_tx_stats(tx_cnf, skb, delay)
+
 #endif
 
 /* This part must be outside protection */

drivers/staging/wfx/wfx.h

@@ -14,8 +14,11 @@
 #include <net/mac80211.h>
 
 #include "bh.h"
+#include "data_tx.h"
 #include "main.h"
+#include "queue.h"
 #include "secure_link.h"
+#include "sta.h"
 #include "hif_tx.h"
 #include "hif_api_general.h"
 
@@ -38,6 +41,10 @@ struct wfx_dev {
 	int			chip_frozen;
 
 	struct wfx_hif_cmd	hif_cmd;
+	struct wfx_queue	tx_queue[4];
+	struct wfx_queue_stats	tx_queue_stats;
+	int			tx_burst_idx;
+	atomic_t		tx_lock;
 
 	struct hif_rx_stats	rx_stats;
 	struct mutex		rx_stats_lock;
@@ -47,6 +54,28 @@ struct wfx_vif {
 	struct wfx_dev		*wdev;
 	struct ieee80211_vif	*vif;
 	int			id;
+
+
+	u32			link_id_map;
+	struct wfx_link_entry	link_id_db[WFX_MAX_STA_IN_AP_MODE];
+	struct delayed_work	link_id_gc_work;
+	struct work_struct	link_id_work;
+
+	bool			aid0_bit_set;
+	bool			mcast_tx;
+	bool			mcast_buffered;
+	struct timer_list	mcast_timeout;
+	struct work_struct	mcast_start_work;
+	struct work_struct	mcast_stop_work;
+
+
+	struct tx_policy_cache	tx_policy_cache;
+	struct work_struct	tx_policy_upload_work;
+	u32			sta_asleep_mask;
+	u32			pspoll_mask;
+	spinlock_t		ps_state_lock;
+
+	struct wfx_edca_params	edca;
 };
 
 static inline struct wfx_vif *wdev_to_wvif(struct wfx_dev *wdev, int vif_id)
@@ -62,4 +91,33 @@ static inline struct wfx_vif *wdev_to_wvif(struct wfx_dev *wdev, int vif_id)
 	return (struct wfx_vif *) wdev->vif[vif_id]->drv_priv;
 }
 
+static inline struct wfx_vif *wvif_iterate(struct wfx_dev *wdev, struct wfx_vif *cur)
+{
+	int i;
+	int mark = 0;
+	struct wfx_vif *tmp;
+
+	if (!cur)
+		mark = 1;
+	for (i = 0; i < ARRAY_SIZE(wdev->vif); i++) {
+		tmp = wdev_to_wvif(wdev, i);
+		if (mark && tmp)
+			return tmp;
+		if (tmp == cur)
+			mark = 1;
+	}
+	return NULL;
+}
+
+static inline int memzcmp(void *src, unsigned int size)
+{
+	uint8_t *buf = src;
+
+	if (!size)
+		return 0;
+	if (*buf)
+		return 1;
+	return memcmp(buf, buf + 1, size - 1);
+}
+
 #endif /* WFX_H */