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btuart.c revision 1.28
      1 /*	$NetBSD: btuart.c,v 1.28 2015/08/20 14:40:17 christos Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2006, 2007 KIYOHARA Takashi
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
     20  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     24  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
     25  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     26  * POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 #include <sys/cdefs.h>
     30 __KERNEL_RCSID(0, "$NetBSD: btuart.c,v 1.28 2015/08/20 14:40:17 christos Exp $");
     31 
     32 #include <sys/param.h>
     33 #include <sys/conf.h>
     34 #include <sys/device.h>
     35 #include <sys/errno.h>
     36 #include <sys/fcntl.h>
     37 #include <sys/kauth.h>
     38 #include <sys/kernel.h>
     39 #include <sys/malloc.h>
     40 #include <sys/mbuf.h>
     41 #include <sys/proc.h>
     42 #include <sys/syslimits.h>
     43 #include <sys/systm.h>
     44 #include <sys/tty.h>
     45 
     46 #include <sys/bus.h>
     47 #include <sys/intr.h>
     48 
     49 #include <netbt/bluetooth.h>
     50 #include <netbt/hci.h>
     51 
     52 #include "ioconf.h"
     53 
     54 struct btuart_softc {
     55 	device_t	sc_dev;
     56 	struct tty *	sc_tp;		/* tty pointer */
     57 
     58 	bool		sc_enabled;	/* device is enabled */
     59 	struct hci_unit *sc_unit;	/* Bluetooth HCI handle */
     60 	struct bt_stats	sc_stats;
     61 
     62 	int		sc_state;	/* receive state */
     63 	int		sc_want;	/* how much we want */
     64 	struct mbuf *	sc_rxp;		/* incoming packet */
     65 
     66 	bool		sc_xmit;	/* transmit is active */
     67 	struct mbuf *	sc_txp;		/* outgoing packet */
     68 
     69 	/* transmit queues */
     70 	MBUFQ_HEAD()	sc_cmdq;
     71 	MBUFQ_HEAD()	sc_aclq;
     72 	MBUFQ_HEAD()	sc_scoq;
     73 };
     74 
     75 /* sc_state */
     76 #define BTUART_RECV_PKT_TYPE	0	/* packet type */
     77 #define BTUART_RECV_ACL_HDR	1	/* acl header */
     78 #define BTUART_RECV_SCO_HDR	2	/* sco header */
     79 #define BTUART_RECV_EVENT_HDR	3	/* event header */
     80 #define BTUART_RECV_ACL_DATA	4	/* acl packet data */
     81 #define BTUART_RECV_SCO_DATA	5	/* sco packet data */
     82 #define BTUART_RECV_EVENT_DATA	6	/* event packet data */
     83 
     84 static int btuart_match(device_t, cfdata_t, void *);
     85 static void btuart_attach(device_t, device_t, void *);
     86 static int btuart_detach(device_t, int);
     87 
     88 static int btuartopen(dev_t, struct tty *);
     89 static int btuartclose(struct tty *, int);
     90 static int btuartioctl(struct tty *, u_long, void *, int, struct lwp *);
     91 static int btuartinput(int, struct tty *);
     92 static int btuartstart(struct tty *);
     93 
     94 static int btuart_enable(device_t);
     95 static void btuart_disable(device_t);
     96 static void btuart_output_cmd(device_t, struct mbuf *);
     97 static void btuart_output_acl(device_t, struct mbuf *);
     98 static void btuart_output_sco(device_t, struct mbuf *);
     99 static void btuart_stats(device_t, struct bt_stats *, int);
    100 
    101 /*
    102  * It doesn't need to be exported, as only btuartattach() uses it,
    103  * but there's no "official" way to make it static.
    104  */
    105 CFATTACH_DECL_NEW(btuart, sizeof(struct btuart_softc),
    106     btuart_match, btuart_attach, btuart_detach, NULL);
    107 
    108 static struct linesw btuart_disc = {
    109 	.l_name =	"btuart",
    110 	.l_open =	btuartopen,
    111 	.l_close =	btuartclose,
    112 	.l_read =	ttyerrio,
    113 	.l_write =	ttyerrio,
    114 	.l_ioctl =	btuartioctl,
    115 	.l_rint =	btuartinput,
    116 	.l_start =	btuartstart,
    117 	.l_modem =	ttymodem,
    118 	.l_poll =	ttyerrpoll,
    119 };
    120 
    121 static const struct hci_if btuart_hci = {
    122 	.enable =	btuart_enable,
    123 	.disable =	btuart_disable,
    124 	.output_cmd =	btuart_output_cmd,
    125 	.output_acl =	btuart_output_acl,
    126 	.output_sco =	btuart_output_sco,
    127 	.get_stats =	btuart_stats,
    128 	.ipl =		IPL_TTY,
    129 };
    130 
    131 /*****************************************************************************
    132  *
    133  *	autoconf(9) functions
    134  */
    135 
    136 /*
    137  * pseudo-device attach routine.
    138  */
    139 void
    140 btuartattach(int num __unused)
    141 {
    142 	int error;
    143 
    144 	error = ttyldisc_attach(&btuart_disc);
    145 	if (error) {
    146 		aprint_error("%s: unable to register line discipline, "
    147 		    "error = %d\n", btuart_cd.cd_name, error);
    148 
    149 		return;
    150 	}
    151 
    152 	error = config_cfattach_attach(btuart_cd.cd_name, &btuart_ca);
    153 	if (error) {
    154 		aprint_error("%s: unable to register cfattach, error = %d\n",
    155 		    btuart_cd.cd_name, error);
    156 
    157 		config_cfdriver_detach(&btuart_cd);
    158 		(void) ttyldisc_detach(&btuart_disc);
    159 	}
    160 }
    161 
    162 /*
    163  * Autoconf match routine.
    164  */
    165 static int
    166 btuart_match(device_t self __unused, cfdata_t cfdata __unused,
    167 	     void *arg __unused)
    168 {
    169 
    170 	/* pseudo-device; always present */
    171 	return 1;
    172 }
    173 
    174 /*
    175  * Autoconf attach routine.
    176  * Called by config_attach_pseudo(9) when we open the line discipline.
    177  */
    178 static void
    179 btuart_attach(device_t parent __unused, device_t self, void *aux __unused)
    180 {
    181 	struct btuart_softc *sc = device_private(self);
    182 
    183 	sc->sc_dev = self;
    184 
    185 	MBUFQ_INIT(&sc->sc_cmdq);
    186 	MBUFQ_INIT(&sc->sc_aclq);
    187 	MBUFQ_INIT(&sc->sc_scoq);
    188 
    189 	/* Attach Bluetooth unit */
    190 	sc->sc_unit = hci_attach_pcb(&btuart_hci, self, 0);
    191 	if (sc->sc_unit == NULL)
    192 		aprint_error_dev(self, "HCI attach failed\n");
    193 }
    194 
    195 /*
    196  * Autoconf detach routine.
    197  * Called when we close the line discipline.
    198  */
    199 static int
    200 btuart_detach(device_t self, int flags __unused)
    201 {
    202 	struct btuart_softc *sc = device_private(self);
    203 
    204 	btuart_disable(self);
    205 
    206 	if (sc->sc_unit) {
    207 		hci_detach_pcb(sc->sc_unit);
    208 		sc->sc_unit = NULL;
    209 	}
    210 
    211 	return 0;
    212 }
    213 
    214 /*****************************************************************************
    215  *
    216  *	Line discipline functions.
    217  */
    218 
    219 static int
    220 btuartopen(dev_t devno __unused, struct tty *tp)
    221 {
    222 	struct btuart_softc *sc;
    223 	device_t dev;
    224 	cfdata_t cfdata;
    225 	struct lwp *l = curlwp;		/* XXX */
    226 	int error, unit, s;
    227 
    228 	error = kauth_authorize_device(l->l_cred, KAUTH_DEVICE_BLUETOOTH_BTUART,
    229 	    KAUTH_ARG(KAUTH_REQ_DEVICE_BLUETOOTH_BTUART_ADD), NULL, NULL, NULL);
    230 	if (error)
    231 		return (error);
    232 
    233 	s = spltty();
    234 
    235 	if (tp->t_linesw == &btuart_disc) {
    236 		sc = tp->t_sc;
    237 		if (sc != NULL) {
    238 			splx(s);
    239 			return EBUSY;
    240 		}
    241 	}
    242 
    243 	KASSERT(tp->t_oproc != NULL);
    244 
    245 	cfdata = malloc(sizeof(struct cfdata), M_DEVBUF, M_WAITOK);
    246 	for (unit = 0; unit < btuart_cd.cd_ndevs; unit++)
    247 		if (device_lookup(&btuart_cd, unit) == NULL)
    248 			break;
    249 
    250 	cfdata->cf_name = btuart_cd.cd_name;
    251 	cfdata->cf_atname = btuart_cd.cd_name;
    252 	cfdata->cf_unit = unit;
    253 	cfdata->cf_fstate = FSTATE_STAR;
    254 
    255 	dev = config_attach_pseudo(cfdata);
    256 	if (dev == NULL) {
    257 		free(cfdata, M_DEVBUF);
    258 		splx(s);
    259 		return EIO;
    260 	}
    261 	sc = device_private(dev);
    262 
    263 	aprint_normal_dev(dev, "major %llu minor %llu\n",
    264 	    (unsigned long long)major(tp->t_dev),
    265 	    (unsigned long long)minor(tp->t_dev));
    266 
    267 	sc->sc_tp = tp;
    268 	tp->t_sc = sc;
    269 
    270 	mutex_spin_enter(&tty_lock);
    271 	ttyflush(tp, FREAD | FWRITE);
    272 	mutex_spin_exit(&tty_lock);
    273 
    274 	splx(s);
    275 
    276 	return 0;
    277 }
    278 
    279 static int
    280 btuartclose(struct tty *tp, int flag __unused)
    281 {
    282 	struct btuart_softc *sc = tp->t_sc;
    283 	cfdata_t cfdata;
    284 	int s;
    285 
    286 	s = spltty();
    287 
    288 	mutex_spin_enter(&tty_lock);
    289 	ttyflush(tp, FREAD | FWRITE);
    290 	mutex_spin_exit(&tty_lock);	/* XXX */
    291 
    292 	ttyldisc_release(tp->t_linesw);
    293 	tp->t_linesw = ttyldisc_default();
    294 
    295 	if (sc != NULL) {
    296 		tp->t_sc = NULL;
    297 		if (sc->sc_tp == tp) {
    298 			cfdata = device_cfdata(sc->sc_dev);
    299 			config_detach(sc->sc_dev, 0);
    300 			free(cfdata, M_DEVBUF);
    301 		}
    302 	}
    303 
    304 	splx(s);
    305 
    306 	return 0;
    307 }
    308 
    309 static int
    310 btuartioctl(struct tty *tp, u_long cmd, void *data __unused,
    311     int flag __unused, struct lwp *l __unused)
    312 {
    313 	struct btuart_softc *sc = tp->t_sc;
    314 	int error;
    315 
    316 	if (sc == NULL || tp != sc->sc_tp)
    317 		return EPASSTHROUGH;
    318 
    319 	switch(cmd) {
    320 	default:
    321 		error = EPASSTHROUGH;
    322 		break;
    323 	}
    324 
    325 	return error;
    326 }
    327 
    328 static int
    329 btuartinput(int c, struct tty *tp)
    330 {
    331 	struct btuart_softc *sc = tp->t_sc;
    332 	struct mbuf *m = sc->sc_rxp;
    333 	int space = 0;
    334 
    335 	if (!sc->sc_enabled)
    336 		return 0;
    337 
    338 	c &= TTY_CHARMASK;
    339 
    340 	/* If we already started a packet, find the trailing end of it. */
    341 	if (m) {
    342 		while (m->m_next)
    343 			m = m->m_next;
    344 
    345 		space = M_TRAILINGSPACE(m);
    346 	}
    347 
    348 	if (space == 0) {
    349 		if (m == NULL) {
    350 			/* new packet */
    351 			MGETHDR(m, M_DONTWAIT, MT_DATA);
    352 			if (m == NULL) {
    353 				aprint_error_dev(sc->sc_dev, "out of memory\n");
    354 				sc->sc_stats.err_rx++;
    355 				return 0;	/* (lost sync) */
    356 			}
    357 
    358 			sc->sc_rxp = m;
    359 			m->m_pkthdr.len = m->m_len = 0;
    360 			space = MHLEN;
    361 
    362 			sc->sc_state = BTUART_RECV_PKT_TYPE;
    363 			sc->sc_want = 1;
    364 		} else {
    365 			/* extend mbuf */
    366 			MGET(m->m_next, M_DONTWAIT, MT_DATA);
    367 			if (m->m_next == NULL) {
    368 				aprint_error_dev(sc->sc_dev, "out of memory\n");
    369 				sc->sc_stats.err_rx++;
    370 				return 0;	/* (lost sync) */
    371 			}
    372 
    373 			m = m->m_next;
    374 			m->m_len = 0;
    375 			space = MLEN;
    376 
    377 			if (sc->sc_want > MINCLSIZE) {
    378 				MCLGET(m, M_DONTWAIT);
    379 				if (m->m_flags & M_EXT)
    380 					space = MCLBYTES;
    381 			}
    382 		}
    383 	}
    384 
    385 	mtod(m, uint8_t *)[m->m_len++] = c;
    386 	sc->sc_rxp->m_pkthdr.len++;
    387 	sc->sc_stats.byte_rx++;
    388 
    389 	sc->sc_want--;
    390 	if (sc->sc_want > 0)
    391 		return 0;	/* want more */
    392 
    393 	switch (sc->sc_state) {
    394 	case BTUART_RECV_PKT_TYPE:	/* Got packet type */
    395 
    396 		switch (c) {
    397 		case HCI_ACL_DATA_PKT:
    398 			sc->sc_state = BTUART_RECV_ACL_HDR;
    399 			sc->sc_want = sizeof(hci_acldata_hdr_t) - 1;
    400 			break;
    401 
    402 		case HCI_SCO_DATA_PKT:
    403 			sc->sc_state = BTUART_RECV_SCO_HDR;
    404 			sc->sc_want = sizeof(hci_scodata_hdr_t) - 1;
    405 			break;
    406 
    407 		case HCI_EVENT_PKT:
    408 			sc->sc_state = BTUART_RECV_EVENT_HDR;
    409 			sc->sc_want = sizeof(hci_event_hdr_t) - 1;
    410 			break;
    411 
    412 		default:
    413 			aprint_error_dev(sc->sc_dev,
    414 			    "Unknown packet type=%#x!\n", c);
    415 			sc->sc_stats.err_rx++;
    416 			m_freem(sc->sc_rxp);
    417 			sc->sc_rxp = NULL;
    418 			return 0;	/* (lost sync) */
    419 		}
    420 
    421 		break;
    422 
    423 	/*
    424 	 * we assume (correctly of course :) that the packet headers all fit
    425 	 * into a single pkthdr mbuf
    426 	 */
    427 	case BTUART_RECV_ACL_HDR:	/* Got ACL Header */
    428 		sc->sc_state = BTUART_RECV_ACL_DATA;
    429 		sc->sc_want = mtod(m, hci_acldata_hdr_t *)->length;
    430 		sc->sc_want = le16toh(sc->sc_want);
    431 		break;
    432 
    433 	case BTUART_RECV_SCO_HDR:	/* Got SCO Header */
    434 		sc->sc_state = BTUART_RECV_SCO_DATA;
    435 		sc->sc_want =  mtod(m, hci_scodata_hdr_t *)->length;
    436 		break;
    437 
    438 	case BTUART_RECV_EVENT_HDR:	/* Got Event Header */
    439 		sc->sc_state = BTUART_RECV_EVENT_DATA;
    440 		sc->sc_want =  mtod(m, hci_event_hdr_t *)->length;
    441 		break;
    442 
    443 	case BTUART_RECV_ACL_DATA:	/* ACL Packet Complete */
    444 		if (!hci_input_acl(sc->sc_unit, sc->sc_rxp))
    445 			sc->sc_stats.err_rx++;
    446 
    447 		sc->sc_stats.acl_rx++;
    448 		sc->sc_rxp = m = NULL;
    449 		break;
    450 
    451 	case BTUART_RECV_SCO_DATA:	/* SCO Packet Complete */
    452 		if (!hci_input_sco(sc->sc_unit, sc->sc_rxp))
    453 			sc->sc_stats.err_rx++;
    454 
    455 		sc->sc_stats.sco_rx++;
    456 		sc->sc_rxp = m = NULL;
    457 		break;
    458 
    459 	case BTUART_RECV_EVENT_DATA:	/* Event Packet Complete */
    460 		if (!hci_input_event(sc->sc_unit, sc->sc_rxp))
    461 			sc->sc_stats.err_rx++;
    462 
    463 		sc->sc_stats.evt_rx++;
    464 		sc->sc_rxp = m = NULL;
    465 		break;
    466 
    467 	default:
    468 		panic("%s: invalid state %d!\n",
    469 		    device_xname(sc->sc_dev), sc->sc_state);
    470 	}
    471 
    472 	return 0;
    473 }
    474 
    475 static int
    476 btuartstart(struct tty *tp)
    477 {
    478 	struct btuart_softc *sc = tp->t_sc;
    479 	struct mbuf *m;
    480 	int count, rlen;
    481 	uint8_t *rptr;
    482 
    483 	if (!sc->sc_enabled)
    484 		return 0;
    485 
    486 	m = sc->sc_txp;
    487 	if (m == NULL) {
    488 		if (MBUFQ_FIRST(&sc->sc_cmdq)) {
    489 			MBUFQ_DEQUEUE(&sc->sc_cmdq, m);
    490 			sc->sc_stats.cmd_tx++;
    491 		} else if (MBUFQ_FIRST(&sc->sc_scoq)) {
    492 			MBUFQ_DEQUEUE(&sc->sc_scoq, m);
    493 			sc->sc_stats.sco_tx++;
    494 		} else if (MBUFQ_FIRST(&sc->sc_aclq)) {
    495 			MBUFQ_DEQUEUE(&sc->sc_aclq, m);
    496 			sc->sc_stats.acl_tx++;
    497 		} else {
    498 			sc->sc_xmit = false;
    499 			return 0; /* no more to send */
    500 		}
    501 
    502 		sc->sc_txp = m;
    503 		sc->sc_xmit = true;
    504 	}
    505 
    506 	count = 0;
    507 	rlen = 0;
    508 	rptr = mtod(m, uint8_t *);
    509 
    510 	for(;;) {
    511 		if (rlen >= m->m_len) {
    512 			m = m->m_next;
    513 			if (m == NULL) {
    514 				m = sc->sc_txp;
    515 				sc->sc_txp = NULL;
    516 
    517 				if (M_GETCTX(m, void *) == NULL)
    518 					m_freem(m);
    519 				else if (!hci_complete_sco(sc->sc_unit, m))
    520 					sc->sc_stats.err_tx++;
    521 
    522 				break;
    523 			}
    524 
    525 			rlen = 0;
    526 			rptr = mtod(m, uint8_t *);
    527 			continue;
    528 		}
    529 
    530 		if (putc(*rptr++, &tp->t_outq) < 0) {
    531 			m_adj(m, rlen);
    532 			break;
    533 		}
    534 		rlen++;
    535 		count++;
    536 	}
    537 
    538 	sc->sc_stats.byte_tx += count;
    539 
    540 	if (tp->t_outq.c_cc != 0)
    541 		(*tp->t_oproc)(tp);
    542 
    543 	return 0;
    544 }
    545 
    546 /*****************************************************************************
    547  *
    548  *	bluetooth(9) functions
    549  */
    550 
    551 static int
    552 btuart_enable(device_t self)
    553 {
    554 	struct btuart_softc *sc = device_private(self);
    555 	int s;
    556 
    557 	if (sc->sc_enabled)
    558 		return 0;
    559 
    560 	s = spltty();
    561 
    562 	sc->sc_enabled = true;
    563 	sc->sc_xmit = false;
    564 
    565 	splx(s);
    566 
    567 	return 0;
    568 }
    569 
    570 static void
    571 btuart_disable(device_t self)
    572 {
    573 	struct btuart_softc *sc = device_private(self);
    574 	int s;
    575 
    576 	if (!sc->sc_enabled)
    577 		return;
    578 
    579 	s = spltty();
    580 
    581 	if (sc->sc_rxp) {
    582 		m_freem(sc->sc_rxp);
    583 		sc->sc_rxp = NULL;
    584 	}
    585 
    586 	if (sc->sc_txp) {
    587 		m_freem(sc->sc_txp);
    588 		sc->sc_txp = NULL;
    589 	}
    590 
    591 	MBUFQ_DRAIN(&sc->sc_cmdq);
    592 	MBUFQ_DRAIN(&sc->sc_aclq);
    593 	MBUFQ_DRAIN(&sc->sc_scoq);
    594 
    595 	sc->sc_enabled = false;
    596 
    597 	splx(s);
    598 }
    599 
    600 static void
    601 btuart_output_cmd(device_t self, struct mbuf *m)
    602 {
    603 	struct btuart_softc *sc = device_private(self);
    604 	int s;
    605 
    606 	KASSERT(sc->sc_enabled);
    607 
    608 	M_SETCTX(m, NULL);
    609 
    610 	s = spltty();
    611 	MBUFQ_ENQUEUE(&sc->sc_cmdq, m);
    612 	if (!sc->sc_xmit)
    613 		btuartstart(sc->sc_tp);
    614 
    615 	splx(s);
    616 }
    617 
    618 static void
    619 btuart_output_acl(device_t self, struct mbuf *m)
    620 {
    621 	struct btuart_softc *sc = device_private(self);
    622 	int s;
    623 
    624 	KASSERT(sc->sc_enabled);
    625 
    626 	M_SETCTX(m, NULL);
    627 
    628 	s = spltty();
    629 	MBUFQ_ENQUEUE(&sc->sc_aclq, m);
    630 	if (!sc->sc_xmit)
    631 		btuartstart(sc->sc_tp);
    632 
    633 	splx(s);
    634 }
    635 
    636 static void
    637 btuart_output_sco(device_t self, struct mbuf *m)
    638 {
    639 	struct btuart_softc *sc = device_private(self);
    640 	int s;
    641 
    642 	KASSERT(sc->sc_enabled);
    643 
    644 	s = spltty();
    645 	MBUFQ_ENQUEUE(&sc->sc_scoq, m);
    646 	if (!sc->sc_xmit)
    647 		btuartstart(sc->sc_tp);
    648 
    649 	splx(s);
    650 }
    651 
    652 static void
    653 btuart_stats(device_t self, struct bt_stats *dest, int flush)
    654 {
    655 	struct btuart_softc *sc = device_private(self);
    656 	int s;
    657 
    658 	s = spltty();
    659 
    660 	memcpy(dest, &sc->sc_stats, sizeof(struct bt_stats));
    661 
    662 	if (flush)
    663 		memset(&sc->sc_stats, 0, sizeof(struct bt_stats));
    664 
    665 	splx(s);
    666 }
    667