xref: /linux/drivers/net/wireless/ath/ath9k/wow.c (revision 4ba24fef3eb3b142197135223b90ced2f319cd53)
1 /*
2  * Copyright (c) 2013 Qualcomm Atheros, Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "ath9k.h"
18 
19 static const struct wiphy_wowlan_support ath9k_wowlan_support = {
20 	.flags = WIPHY_WOWLAN_MAGIC_PKT | WIPHY_WOWLAN_DISCONNECT,
21 	.n_patterns = MAX_NUM_USER_PATTERN,
22 	.pattern_min_len = 1,
23 	.pattern_max_len = MAX_PATTERN_SIZE,
24 };
25 
26 static void ath9k_wow_map_triggers(struct ath_softc *sc,
27 				   struct cfg80211_wowlan *wowlan,
28 				   u32 *wow_triggers)
29 {
30 	if (wowlan->disconnect)
31 		*wow_triggers |= AH_WOW_LINK_CHANGE |
32 				 AH_WOW_BEACON_MISS;
33 	if (wowlan->magic_pkt)
34 		*wow_triggers |= AH_WOW_MAGIC_PATTERN_EN;
35 
36 	if (wowlan->n_patterns)
37 		*wow_triggers |= AH_WOW_USER_PATTERN_EN;
38 
39 	sc->wow_enabled = *wow_triggers;
40 
41 }
42 
43 static void ath9k_wow_add_disassoc_deauth_pattern(struct ath_softc *sc)
44 {
45 	struct ath_hw *ah = sc->sc_ah;
46 	struct ath_common *common = ath9k_hw_common(ah);
47 	int pattern_count = 0;
48 	int i, byte_cnt;
49 	u8 dis_deauth_pattern[MAX_PATTERN_SIZE];
50 	u8 dis_deauth_mask[MAX_PATTERN_SIZE];
51 
52 	memset(dis_deauth_pattern, 0, MAX_PATTERN_SIZE);
53 	memset(dis_deauth_mask, 0, MAX_PATTERN_SIZE);
54 
55 	/*
56 	 * Create Dissassociate / Deauthenticate packet filter
57 	 *
58 	 *     2 bytes        2 byte    6 bytes   6 bytes  6 bytes
59 	 *  +--------------+----------+---------+--------+--------+----
60 	 *  + Frame Control+ Duration +   DA    +  SA    +  BSSID +
61 	 *  +--------------+----------+---------+--------+--------+----
62 	 *
63 	 * The above is the management frame format for disassociate/
64 	 * deauthenticate pattern, from this we need to match the first byte
65 	 * of 'Frame Control' and DA, SA, and BSSID fields
66 	 * (skipping 2nd byte of FC and Duration feild.
67 	 *
68 	 * Disassociate pattern
69 	 * --------------------
70 	 * Frame control = 00 00 1010
71 	 * DA, SA, BSSID = x:x:x:x:x:x
72 	 * Pattern will be A0000000 | x:x:x:x:x:x | x:x:x:x:x:x
73 	 *			    | x:x:x:x:x:x  -- 22 bytes
74 	 *
75 	 * Deauthenticate pattern
76 	 * ----------------------
77 	 * Frame control = 00 00 1100
78 	 * DA, SA, BSSID = x:x:x:x:x:x
79 	 * Pattern will be C0000000 | x:x:x:x:x:x | x:x:x:x:x:x
80 	 *			    | x:x:x:x:x:x  -- 22 bytes
81 	 */
82 
83 	/* Create Disassociate Pattern first */
84 
85 	byte_cnt = 0;
86 
87 	/* Fill out the mask with all FF's */
88 
89 	for (i = 0; i < MAX_PATTERN_MASK_SIZE; i++)
90 		dis_deauth_mask[i] = 0xff;
91 
92 	/* copy the first byte of frame control field */
93 	dis_deauth_pattern[byte_cnt] = 0xa0;
94 	byte_cnt++;
95 
96 	/* skip 2nd byte of frame control and Duration field */
97 	byte_cnt += 3;
98 
99 	/*
100 	 * need not match the destination mac address, it can be a broadcast
101 	 * mac address or an unicast to this station
102 	 */
103 	byte_cnt += 6;
104 
105 	/* copy the source mac address */
106 	memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);
107 
108 	byte_cnt += 6;
109 
110 	/* copy the bssid, its same as the source mac address */
111 
112 	memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);
113 
114 	/* Create Disassociate pattern mask */
115 
116 	dis_deauth_mask[0] = 0xfe;
117 	dis_deauth_mask[1] = 0x03;
118 	dis_deauth_mask[2] = 0xc0;
119 
120 	ath_dbg(common, WOW, "Adding disassoc/deauth patterns for WoW\n");
121 
122 	ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
123 				   pattern_count, byte_cnt);
124 
125 	pattern_count++;
126 	/*
127 	 * for de-authenticate pattern, only the first byte of the frame
128 	 * control field gets changed from 0xA0 to 0xC0
129 	 */
130 	dis_deauth_pattern[0] = 0xC0;
131 
132 	ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
133 				   pattern_count, byte_cnt);
134 
135 }
136 
137 static void ath9k_wow_add_pattern(struct ath_softc *sc,
138 				  struct cfg80211_wowlan *wowlan)
139 {
140 	struct ath_hw *ah = sc->sc_ah;
141 	struct ath9k_wow_pattern *wow_pattern = NULL;
142 	struct cfg80211_pkt_pattern *patterns = wowlan->patterns;
143 	int mask_len;
144 	s8 i = 0;
145 
146 	if (!wowlan->n_patterns)
147 		return;
148 
149 	/*
150 	 * Add the new user configured patterns
151 	 */
152 	for (i = 0; i < wowlan->n_patterns; i++) {
153 
154 		wow_pattern = kzalloc(sizeof(*wow_pattern), GFP_KERNEL);
155 
156 		if (!wow_pattern)
157 			return;
158 
159 		/*
160 		 * TODO: convert the generic user space pattern to
161 		 * appropriate chip specific/802.11 pattern.
162 		 */
163 
164 		mask_len = DIV_ROUND_UP(wowlan->patterns[i].pattern_len, 8);
165 		memset(wow_pattern->pattern_bytes, 0, MAX_PATTERN_SIZE);
166 		memset(wow_pattern->mask_bytes, 0, MAX_PATTERN_SIZE);
167 		memcpy(wow_pattern->pattern_bytes, patterns[i].pattern,
168 		       patterns[i].pattern_len);
169 		memcpy(wow_pattern->mask_bytes, patterns[i].mask, mask_len);
170 		wow_pattern->pattern_len = patterns[i].pattern_len;
171 
172 		/*
173 		 * just need to take care of deauth and disssoc pattern,
174 		 * make sure we don't overwrite them.
175 		 */
176 
177 		ath9k_hw_wow_apply_pattern(ah, wow_pattern->pattern_bytes,
178 					   wow_pattern->mask_bytes,
179 					   i + 2,
180 					   wow_pattern->pattern_len);
181 		kfree(wow_pattern);
182 
183 	}
184 
185 }
186 
187 int ath9k_suspend(struct ieee80211_hw *hw,
188 		  struct cfg80211_wowlan *wowlan)
189 {
190 	struct ath_softc *sc = hw->priv;
191 	struct ath_hw *ah = sc->sc_ah;
192 	struct ath_common *common = ath9k_hw_common(ah);
193 	u32 wow_triggers_enabled = 0;
194 	int ret = 0;
195 
196 	ath9k_deinit_channel_context(sc);
197 
198 	mutex_lock(&sc->mutex);
199 
200 	ath_cancel_work(sc);
201 	ath_stop_ani(sc);
202 
203 	if (test_bit(ATH_OP_INVALID, &common->op_flags)) {
204 		ath_dbg(common, ANY, "Device not present\n");
205 		ret = -EINVAL;
206 		goto fail_wow;
207 	}
208 
209 	if (WARN_ON(!wowlan)) {
210 		ath_dbg(common, WOW, "None of the WoW triggers enabled\n");
211 		ret = -EINVAL;
212 		goto fail_wow;
213 	}
214 
215 	if (!device_can_wakeup(sc->dev)) {
216 		ath_dbg(common, WOW, "device_can_wakeup failed, WoW is not enabled\n");
217 		ret = 1;
218 		goto fail_wow;
219 	}
220 
221 	/*
222 	 * none of the sta vifs are associated
223 	 * and we are not currently handling multivif
224 	 * cases, for instance we have to seperately
225 	 * configure 'keep alive frame' for each
226 	 * STA.
227 	 */
228 
229 	if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags)) {
230 		ath_dbg(common, WOW, "None of the STA vifs are associated\n");
231 		ret = 1;
232 		goto fail_wow;
233 	}
234 
235 	if (sc->cur_chan->nvifs > 1) {
236 		ath_dbg(common, WOW, "WoW for multivif is not yet supported\n");
237 		ret = 1;
238 		goto fail_wow;
239 	}
240 
241 	ath9k_wow_map_triggers(sc, wowlan, &wow_triggers_enabled);
242 
243 	ath_dbg(common, WOW, "WoW triggers enabled 0x%x\n",
244 		wow_triggers_enabled);
245 
246 	ath9k_ps_wakeup(sc);
247 
248 	ath9k_stop_btcoex(sc);
249 
250 	/*
251 	 * Enable wake up on recieving disassoc/deauth
252 	 * frame by default.
253 	 */
254 	ath9k_wow_add_disassoc_deauth_pattern(sc);
255 
256 	if (wow_triggers_enabled & AH_WOW_USER_PATTERN_EN)
257 		ath9k_wow_add_pattern(sc, wowlan);
258 
259 	spin_lock_bh(&sc->sc_pcu_lock);
260 	/*
261 	 * To avoid false wake, we enable beacon miss interrupt only
262 	 * when we go to sleep. We save the current interrupt mask
263 	 * so we can restore it after the system wakes up
264 	 */
265 	sc->wow_intr_before_sleep = ah->imask;
266 	ah->imask &= ~ATH9K_INT_GLOBAL;
267 	ath9k_hw_disable_interrupts(ah);
268 	ah->imask = ATH9K_INT_BMISS | ATH9K_INT_GLOBAL;
269 	ath9k_hw_set_interrupts(ah);
270 	ath9k_hw_enable_interrupts(ah);
271 
272 	spin_unlock_bh(&sc->sc_pcu_lock);
273 
274 	/*
275 	 * we can now sync irq and kill any running tasklets, since we already
276 	 * disabled interrupts and not holding a spin lock
277 	 */
278 	synchronize_irq(sc->irq);
279 	tasklet_kill(&sc->intr_tq);
280 
281 	ath9k_hw_wow_enable(ah, wow_triggers_enabled);
282 
283 	ath9k_ps_restore(sc);
284 	ath_dbg(common, ANY, "WoW enabled in ath9k\n");
285 	atomic_inc(&sc->wow_sleep_proc_intr);
286 
287 fail_wow:
288 	mutex_unlock(&sc->mutex);
289 	return ret;
290 }
291 
292 int ath9k_resume(struct ieee80211_hw *hw)
293 {
294 	struct ath_softc *sc = hw->priv;
295 	struct ath_hw *ah = sc->sc_ah;
296 	struct ath_common *common = ath9k_hw_common(ah);
297 	u32 wow_status;
298 
299 	mutex_lock(&sc->mutex);
300 
301 	ath9k_ps_wakeup(sc);
302 
303 	spin_lock_bh(&sc->sc_pcu_lock);
304 
305 	ath9k_hw_disable_interrupts(ah);
306 	ah->imask = sc->wow_intr_before_sleep;
307 	ath9k_hw_set_interrupts(ah);
308 	ath9k_hw_enable_interrupts(ah);
309 
310 	spin_unlock_bh(&sc->sc_pcu_lock);
311 
312 	wow_status = ath9k_hw_wow_wakeup(ah);
313 
314 	if (atomic_read(&sc->wow_got_bmiss_intr) == 0) {
315 		/*
316 		 * some devices may not pick beacon miss
317 		 * as the reason they woke up so we add
318 		 * that here for that shortcoming.
319 		 */
320 		wow_status |= AH_WOW_BEACON_MISS;
321 		atomic_dec(&sc->wow_got_bmiss_intr);
322 		ath_dbg(common, ANY, "Beacon miss interrupt picked up during WoW sleep\n");
323 	}
324 
325 	atomic_dec(&sc->wow_sleep_proc_intr);
326 
327 	if (wow_status) {
328 		ath_dbg(common, ANY, "Waking up due to WoW triggers %s with WoW status = %x\n",
329 			ath9k_hw_wow_event_to_string(wow_status), wow_status);
330 	}
331 
332 	ath_restart_work(sc);
333 	ath9k_start_btcoex(sc);
334 
335 	ath9k_ps_restore(sc);
336 	mutex_unlock(&sc->mutex);
337 
338 	return 0;
339 }
340 
341 void ath9k_set_wakeup(struct ieee80211_hw *hw, bool enabled)
342 {
343 	struct ath_softc *sc = hw->priv;
344 
345 	mutex_lock(&sc->mutex);
346 	device_init_wakeup(sc->dev, 1);
347 	device_set_wakeup_enable(sc->dev, enabled);
348 	mutex_unlock(&sc->mutex);
349 }
350 
351 void ath9k_init_wow(struct ieee80211_hw *hw)
352 {
353 	struct ath_softc *sc = hw->priv;
354 
355 	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_WOW_DEVICE_CAPABLE) &&
356 	    (sc->driver_data & ATH9K_PCI_WOW) &&
357 	    device_can_wakeup(sc->dev))
358 		hw->wiphy->wowlan = &ath9k_wowlan_support;
359 
360 	atomic_set(&sc->wow_sleep_proc_intr, -1);
361 	atomic_set(&sc->wow_got_bmiss_intr, -1);
362 }
363