btcoex.c

  1// SPDX-License-Identifier: ISC
  2/*
  3 * Copyright (c) 2013 Broadcom Corporation
  4 */
  5#include <linux/slab.h>
  6#include <linux/netdevice.h>
  7#include <net/cfg80211.h>
  8
  9#include <brcmu_wifi.h>
 10#include <brcmu_utils.h>
 11#include <defs.h>
 12#include "core.h"
 13#include "debug.h"
 14#include "fwil.h"
 15#include "fwil_types.h"
 16#include "btcoex.h"
 17#include "p2p.h"
 18#include "cfg80211.h"
 19
 20/* T1 start SCO/eSCO priority suppression */
 21#define BRCMF_BTCOEX_OPPR_WIN_TIME   msecs_to_jiffies(2000)
 22
 23/* BT registers values during DHCP */
 24#define BRCMF_BT_DHCP_REG50 0x8022
 25#define BRCMF_BT_DHCP_REG51 0
 26#define BRCMF_BT_DHCP_REG64 0
 27#define BRCMF_BT_DHCP_REG65 0
 28#define BRCMF_BT_DHCP_REG71 0
 29#define BRCMF_BT_DHCP_REG66 0x2710
 30#define BRCMF_BT_DHCP_REG41 0x33
 31#define BRCMF_BT_DHCP_REG68 0x190
 32
 33/* number of samples for SCO detection */
 34#define BRCMF_BT_SCO_SAMPLES 12
 35
 36/**
 37* enum brcmf_btcoex_state - BT coex DHCP state machine states
 38* @BRCMF_BT_DHCP_IDLE: DCHP is idle
 39* @BRCMF_BT_DHCP_START: DHCP started, wait before
 40*	boosting wifi priority
 41* @BRCMF_BT_DHCP_OPPR_WIN: graceful DHCP opportunity ended,
 42*	boost wifi priority
 43* @BRCMF_BT_DHCP_FLAG_FORCE_TIMEOUT: wifi priority boost end,
 44*	restore defaults
 45*/
 46enum brcmf_btcoex_state {
 47	BRCMF_BT_DHCP_IDLE,
 48	BRCMF_BT_DHCP_START,
 49	BRCMF_BT_DHCP_OPPR_WIN,
 50	BRCMF_BT_DHCP_FLAG_FORCE_TIMEOUT
 51};
 52
 53/**
 54 * struct brcmf_btcoex_info - BT coex related information
 55 * @vif: interface for which request was done.
 56 * @timer: timer for DHCP state machine
 57 * @timeout: configured timeout.
 58 * @timer_on:  DHCP timer active
 59 * @dhcp_done: DHCP finished before T1/T2 timer expiration
 60 * @bt_state: DHCP state machine state
 61 * @work: DHCP state machine work
 62 * @cfg: driver private data for cfg80211 interface
 63 * @reg66: saved value of btc_params 66
 64 * @reg41: saved value of btc_params 41
 65 * @reg68: saved value of btc_params 68
 66 * @saved_regs_part1: flag indicating regs 66,41,68
 67 *	have been saved
 68 * @reg50: saved value of btc_params 50
 69 * @reg51: saved value of btc_params 51
 70 * @reg64: saved value of btc_params 64
 71 * @reg65: saved value of btc_params 65
 72 * @reg71: saved value of btc_params 71
 73 * @saved_regs_part2: flag indicating regs 50,51,64,65,71
 74 *	have been saved
 75 */
 76struct brcmf_btcoex_info {
 77	struct brcmf_cfg80211_vif *vif;
 78	struct timer_list timer;
 79	u16 timeout;
 80	bool timer_on;
 81	bool dhcp_done;
 82	enum brcmf_btcoex_state bt_state;
 83	struct work_struct work;
 84	struct brcmf_cfg80211_info *cfg;
 85	u32 reg66;
 86	u32 reg41;
 87	u32 reg68;
 88	bool saved_regs_part1;
 89	u32 reg50;
 90	u32 reg51;
 91	u32 reg64;
 92	u32 reg65;
 93	u32 reg71;
 94	bool saved_regs_part2;
 95};
 96
 97/**
 98 * brcmf_btcoex_params_write() - write btc_params firmware variable
 99 * @ifp: interface
100 * @addr: btc_params register number
101 * @data: data to write
102 */
103static s32 brcmf_btcoex_params_write(struct brcmf_if *ifp, u32 addr, u32 data)
104{
105	struct {
106		__le32 addr;
107		__le32 data;
108	} reg_write;
109
110	reg_write.addr = cpu_to_le32(addr);
111	reg_write.data = cpu_to_le32(data);
112	return brcmf_fil_iovar_data_set(ifp, "btc_params",
113					&reg_write, sizeof(reg_write));
114}
115
116/**
117 * brcmf_btcoex_params_read() - read btc_params firmware variable
118 * @ifp: interface
119 * @addr: btc_params register number
120 * @data: read data
121 */
122static s32 brcmf_btcoex_params_read(struct brcmf_if *ifp, u32 addr, u32 *data)
123{
124	*data = addr;
125
126	return brcmf_fil_iovar_int_query(ifp, "btc_params", data);
127}
128
129/**
130 * brcmf_btcoex_boost_wifi() - control BT SCO/eSCO parameters
131 * @btci: BT coex info
132 * @trump_sco:
133 *	true - set SCO/eSCO parameters for compatibility
134 *		during DHCP window
135 *	false - restore saved parameter values
136 *
137 * Enhanced BT COEX settings for eSCO compatibility during DHCP window
138 */
139static void brcmf_btcoex_boost_wifi(struct brcmf_btcoex_info *btci,
140				    bool trump_sco)
141{
142	struct brcmf_if *ifp = brcmf_get_ifp(btci->cfg->pub, 0);
143
144	if (trump_sco && !btci->saved_regs_part2) {
145		/* this should reduce eSCO agressive
146		 * retransmit w/o breaking it
147		 */
148
149		/* save current */
150		brcmf_dbg(INFO, "new SCO/eSCO coex algo {save & override}\n");
151		brcmf_btcoex_params_read(ifp, 50, &btci->reg50);
152		brcmf_btcoex_params_read(ifp, 51, &btci->reg51);
153		brcmf_btcoex_params_read(ifp, 64, &btci->reg64);
154		brcmf_btcoex_params_read(ifp, 65, &btci->reg65);
155		brcmf_btcoex_params_read(ifp, 71, &btci->reg71);
156
157		btci->saved_regs_part2 = true;
158		brcmf_dbg(INFO,
159			  "saved bt_params[50,51,64,65,71]: 0x%x 0x%x 0x%x 0x%x 0x%x\n",
160			  btci->reg50, btci->reg51, btci->reg64,
161			  btci->reg65, btci->reg71);
162
163		/* pacify the eSco   */
164		brcmf_btcoex_params_write(ifp, 50, BRCMF_BT_DHCP_REG50);
165		brcmf_btcoex_params_write(ifp, 51, BRCMF_BT_DHCP_REG51);
166		brcmf_btcoex_params_write(ifp, 64, BRCMF_BT_DHCP_REG64);
167		brcmf_btcoex_params_write(ifp, 65, BRCMF_BT_DHCP_REG65);
168		brcmf_btcoex_params_write(ifp, 71, BRCMF_BT_DHCP_REG71);
169
170	} else if (btci->saved_regs_part2) {
171		/* restore previously saved bt params */
172		brcmf_dbg(INFO, "Do new SCO/eSCO coex algo {restore}\n");
173		brcmf_btcoex_params_write(ifp, 50, btci->reg50);
174		brcmf_btcoex_params_write(ifp, 51, btci->reg51);
175		brcmf_btcoex_params_write(ifp, 64, btci->reg64);
176		brcmf_btcoex_params_write(ifp, 65, btci->reg65);
177		brcmf_btcoex_params_write(ifp, 71, btci->reg71);
178
179		brcmf_dbg(INFO,
180			  "restored bt_params[50,51,64,65,71]: 0x%x 0x%x 0x%x 0x%x 0x%x\n",
181			  btci->reg50, btci->reg51, btci->reg64,
182			  btci->reg65, btci->reg71);
183
184		btci->saved_regs_part2 = false;
185	} else {
186		brcmf_dbg(INFO, "attempted to restore not saved BTCOEX params\n");
187	}
188}
189
190/**
191 * brcmf_btcoex_is_sco_active() - check if SCO/eSCO is active
192 * @ifp: interface
193 *
194 * return: true if SCO/eSCO session is active
195 */
196static bool brcmf_btcoex_is_sco_active(struct brcmf_if *ifp)
197{
198	int ioc_res = 0;
199	bool res = false;
200	int sco_id_cnt = 0;
201	u32 param27;
202	int i;
203
204	for (i = 0; i < BRCMF_BT_SCO_SAMPLES; i++) {
205		ioc_res = brcmf_btcoex_params_read(ifp, 27, &param27);
206
207		if (ioc_res < 0) {
208			brcmf_err("ioc read btc params error\n");
209			break;
210		}
211
212		brcmf_dbg(INFO, "sample[%d], btc_params 27:%x\n", i, param27);
213
214		if ((param27 & 0x6) == 2) { /* count both sco & esco  */
215			sco_id_cnt++;
216		}
217
218		if (sco_id_cnt > 2) {
219			brcmf_dbg(INFO,
220				  "sco/esco detected, pkt id_cnt:%d samples:%d\n",
221				  sco_id_cnt, i);
222			res = true;
223			break;
224		}
225	}
226	brcmf_dbg(TRACE, "exit: result=%d\n", res);
227	return res;
228}
229
230/*
231 * btcmf_btcoex_save_part1() - save first step parameters.
232 */
233static void btcmf_btcoex_save_part1(struct brcmf_btcoex_info *btci)
234{
235	struct brcmf_if *ifp = btci->vif->ifp;
236
237	if (!btci->saved_regs_part1) {
238		/* Retrieve and save original reg value */
239		brcmf_btcoex_params_read(ifp, 66, &btci->reg66);
240		brcmf_btcoex_params_read(ifp, 41, &btci->reg41);
241		brcmf_btcoex_params_read(ifp, 68, &btci->reg68);
242		btci->saved_regs_part1 = true;
243		brcmf_dbg(INFO,
244			  "saved btc_params regs (66,41,68) 0x%x 0x%x 0x%x\n",
245			  btci->reg66, btci->reg41,
246			  btci->reg68);
247	}
248}
249
250/*
251 * brcmf_btcoex_restore_part1() - restore first step parameters.
252 */
253static void brcmf_btcoex_restore_part1(struct brcmf_btcoex_info *btci)
254{
255	struct brcmf_if *ifp;
256
257	if (btci->saved_regs_part1) {
258		btci->saved_regs_part1 = false;
259		ifp = btci->vif->ifp;
260		brcmf_btcoex_params_write(ifp, 66, btci->reg66);
261		brcmf_btcoex_params_write(ifp, 41, btci->reg41);
262		brcmf_btcoex_params_write(ifp, 68, btci->reg68);
263		brcmf_dbg(INFO,
264			  "restored btc_params regs {66,41,68} 0x%x 0x%x 0x%x\n",
265			  btci->reg66, btci->reg41,
266			  btci->reg68);
267	}
268}
269
270/*
271 * brcmf_btcoex_timerfunc() - BT coex timer callback
272 */
273static void brcmf_btcoex_timerfunc(struct timer_list *t)
274{
275	struct brcmf_btcoex_info *bt_local = timer_container_of(bt_local, t,
276								timer);
277	brcmf_dbg(TRACE, "enter\n");
278
279	bt_local->timer_on = false;
280	schedule_work(&bt_local->work);
281}
282
283/**
284 * brcmf_btcoex_handler() - BT coex state machine work handler
285 * @work: work
286 */
287static void brcmf_btcoex_handler(struct work_struct *work)
288{
289	struct brcmf_btcoex_info *btci;
290	btci = container_of(work, struct brcmf_btcoex_info, work);
291	if (btci->timer_on) {
292		btci->timer_on = false;
293		timer_delete_sync(&btci->timer);
294	}
295
296	switch (btci->bt_state) {
297	case BRCMF_BT_DHCP_START:
298		/* DHCP started provide OPPORTUNITY window
299		   to get DHCP address
300		*/
301		brcmf_dbg(INFO, "DHCP started\n");
302		btci->bt_state = BRCMF_BT_DHCP_OPPR_WIN;
303		if (btci->timeout < BRCMF_BTCOEX_OPPR_WIN_TIME) {
304			mod_timer(&btci->timer, btci->timer.expires);
305		} else {
306			btci->timeout -= BRCMF_BTCOEX_OPPR_WIN_TIME;
307			mod_timer(&btci->timer,
308				  jiffies + BRCMF_BTCOEX_OPPR_WIN_TIME);
309		}
310		btci->timer_on = true;
311		break;
312
313	case BRCMF_BT_DHCP_OPPR_WIN:
314		if (btci->dhcp_done) {
315			brcmf_dbg(INFO, "DHCP done before T1 expiration\n");
316			goto idle;
317		}
318
319		/* DHCP is not over yet, start lowering BT priority */
320		brcmf_dbg(INFO, "DHCP T1:%d expired\n",
321			  jiffies_to_msecs(BRCMF_BTCOEX_OPPR_WIN_TIME));
322		brcmf_btcoex_boost_wifi(btci, true);
323
324		btci->bt_state = BRCMF_BT_DHCP_FLAG_FORCE_TIMEOUT;
325		mod_timer(&btci->timer, jiffies + btci->timeout);
326		btci->timer_on = true;
327		break;
328
329	case BRCMF_BT_DHCP_FLAG_FORCE_TIMEOUT:
330		if (btci->dhcp_done)
331			brcmf_dbg(INFO, "DHCP done before T2 expiration\n");
332		else
333			brcmf_dbg(INFO, "DHCP T2:%d expired\n",
334				  BRCMF_BT_DHCP_FLAG_FORCE_TIMEOUT);
335
336		goto idle;
337
338	default:
339		brcmf_err("invalid state=%d !!!\n", btci->bt_state);
340		goto idle;
341	}
342
343	return;
344
345idle:
346	btci->bt_state = BRCMF_BT_DHCP_IDLE;
347	btci->timer_on = false;
348	brcmf_btcoex_boost_wifi(btci, false);
349	cfg80211_crit_proto_stopped(&btci->vif->wdev, GFP_KERNEL);
350	brcmf_btcoex_restore_part1(btci);
351	btci->vif = NULL;
352}
353
354/**
355 * brcmf_btcoex_attach() - initialize BT coex data
356 * @cfg: driver private cfg80211 data
357 *
358 * return: 0 on success
359 */
360int brcmf_btcoex_attach(struct brcmf_cfg80211_info *cfg)
361{
362	struct brcmf_btcoex_info *btci;
363	brcmf_dbg(TRACE, "enter\n");
364
365	btci = kmalloc(sizeof(*btci), GFP_KERNEL);
366	if (!btci)
367		return -ENOMEM;
368
369	btci->bt_state = BRCMF_BT_DHCP_IDLE;
370
371	/* Set up timer for BT  */
372	btci->timer_on = false;
373	btci->timeout = BRCMF_BTCOEX_OPPR_WIN_TIME;
374	timer_setup(&btci->timer, brcmf_btcoex_timerfunc, 0);
375	btci->cfg = cfg;
376	btci->saved_regs_part1 = false;
377	btci->saved_regs_part2 = false;
378
379	INIT_WORK(&btci->work, brcmf_btcoex_handler);
380
381	cfg->btcoex = btci;
382	return 0;
383}
384
385/**
386 * brcmf_btcoex_detach - clean BT coex data
387 * @cfg: driver private cfg80211 data
388 */
389void brcmf_btcoex_detach(struct brcmf_cfg80211_info *cfg)
390{
391	brcmf_dbg(TRACE, "enter\n");
392
393	if (!cfg->btcoex)
394		return;
395
396	timer_shutdown_sync(&cfg->btcoex->timer);
397	cfg->btcoex->timer_on = false;
398
399	cancel_work_sync(&cfg->btcoex->work);
400
401	brcmf_btcoex_boost_wifi(cfg->btcoex, false);
402	brcmf_btcoex_restore_part1(cfg->btcoex);
403
404	kfree(cfg->btcoex);
405	cfg->btcoex = NULL;
406}
407
408static void brcmf_btcoex_dhcp_start(struct brcmf_btcoex_info *btci)
409{
410	struct brcmf_if *ifp = btci->vif->ifp;
411
412	btcmf_btcoex_save_part1(btci);
413	/* set new regs values */
414	brcmf_btcoex_params_write(ifp, 66, BRCMF_BT_DHCP_REG66);
415	brcmf_btcoex_params_write(ifp, 41, BRCMF_BT_DHCP_REG41);
416	brcmf_btcoex_params_write(ifp, 68, BRCMF_BT_DHCP_REG68);
417	btci->dhcp_done = false;
418	btci->bt_state = BRCMF_BT_DHCP_START;
419	schedule_work(&btci->work);
420	brcmf_dbg(TRACE, "enable BT DHCP Timer\n");
421}
422
423static void brcmf_btcoex_dhcp_end(struct brcmf_btcoex_info *btci)
424{
425	/* Stop any bt timer because DHCP session is done */
426	btci->dhcp_done = true;
427	if (btci->timer_on) {
428		brcmf_dbg(INFO, "disable BT DHCP Timer\n");
429		btci->timer_on = false;
430		timer_delete_sync(&btci->timer);
431
432		/* schedule worker if transition to IDLE is needed */
433		if (btci->bt_state != BRCMF_BT_DHCP_IDLE) {
434			brcmf_dbg(INFO, "bt_state:%d\n",
435				  btci->bt_state);
436			schedule_work(&btci->work);
437		}
438	} else {
439		/* Restore original values */
440		brcmf_btcoex_restore_part1(btci);
441	}
442}
443
444/*
445 * brcmf_btcoex_set_mode - set BT coex mode
446 * @mode: Wifi-Bluetooth coexistence mode
447 *
448 * return: 0 on success
449 */
450int brcmf_btcoex_set_mode(struct brcmf_cfg80211_vif *vif,
451			  enum brcmf_btcoex_mode mode, u16 duration)
452{
453	struct brcmf_cfg80211_info *cfg = wiphy_to_cfg(vif->wdev.wiphy);
454	struct brcmf_btcoex_info *btci = cfg->btcoex;
455	struct brcmf_if *ifp = brcmf_get_ifp(cfg->pub, 0);
456
457	switch (mode) {
458	case BRCMF_BTCOEX_DISABLED:
459		brcmf_dbg(INFO, "DHCP session starts\n");
460		if (btci->bt_state != BRCMF_BT_DHCP_IDLE)
461			return -EBUSY;
462		/* Start BT timer only for SCO connection */
463		if (brcmf_btcoex_is_sco_active(ifp)) {
464			btci->timeout = msecs_to_jiffies(duration);
465			btci->vif = vif;
466			brcmf_btcoex_dhcp_start(btci);
467		}
468		break;
469
470	case BRCMF_BTCOEX_ENABLED:
471		brcmf_dbg(INFO, "DHCP session ends\n");
472		if (btci->bt_state != BRCMF_BT_DHCP_IDLE &&
473		    vif == btci->vif) {
474			brcmf_btcoex_dhcp_end(btci);
475		}
476		break;
477	default:
478		brcmf_dbg(INFO, "Unknown mode, ignored\n");
479	}
480	return 0;
481}