X-Git-Url: http://rtime.felk.cvut.cz/gitweb/linux-lin.git/blobdiff_plain/53858634cb63490fe6154231aab1f2154b7ad89a..31ae3a0c954665088c5ccf31193f648c05a47ad2:/sllin/sllin.c diff --git a/sllin/sllin.c b/sllin/sllin.c index ce8709f..0f7bff3 100644 --- a/sllin/sllin.c +++ b/sllin/sllin.c @@ -57,6 +57,8 @@ #include #include #include +#include +#include /* Should be in include/linux/tty.h */ #define N_SLLIN 25 @@ -70,6 +72,7 @@ MODULE_LICENSE("GPL"); MODULE_AUTHOR("Oliver Hartkopp "); #define SLLIN_MAGIC 0x53CA +// #define BREAK_BY_BAUD static int maxdev = 10; /* MAX number of SLLIN channels; This can be overridden with @@ -77,8 +80,24 @@ static int maxdev = 10; /* MAX number of SLLIN channels; module_param(maxdev, int, 0); MODULE_PARM_DESC(maxdev, "Maximum number of sllin interfaces"); -/* maximum rx buffer len: extended CAN frame with timestamp */ -#define SLC_MTU (sizeof("T1111222281122334455667788EA5F\r")+1) +/* maximum buffer len to store whole LIN message*/ +#define SLLIN_DATA_MAX 8 +#define SLLIN_BUFF_LEN (1 /*break*/ + 1 /*sync*/ + 1 /*ID*/ + \ + SLLIN_DATA_MAX + 1 /*checksum*/) +#define SLLIN_BUFF_BREAK 0 +#define SLLIN_BUFF_SYNC 1 +#define SLLIN_BUFF_ID 2 +#define SLLIN_BUFF_DATA 3 + +#define SLLIN_ID_MASK 0x3f + +enum slstate { + SLSTATE_IDLE = 0, + SLSTATE_BREAK_SENT, + SLSTATE_ID_SENT, + SLSTATE_RESPONSE_WAIT, + SLSTATE_RESPONSE_SENT, +}; struct sllin { int magic; @@ -88,24 +107,48 @@ struct sllin { struct net_device *dev; /* easy for intr handling */ spinlock_t lock; - /* These are pointers to the malloc()ed frame buffers. */ - unsigned char rbuff[SLC_MTU]; /* receiver buffer */ - int rcount; /* received chars counter */ - unsigned char xbuff[SLC_MTU]; /* transmitter buffer */ - unsigned char *xhead; /* pointer to next XMIT byte */ - int xleft; /* bytes left in XMIT queue */ + /* LIN message buffer and actual processed data counts */ + unsigned char rx_buff[SLLIN_BUFF_LEN]; /* LIN Rx buffer */ + unsigned char tx_buff[SLLIN_BUFF_LEN]; /* LIN Tx buffer */ + int rx_expect; /* expected number of Rx chars */ + int rx_lim; /* maximum Rx chars for current frame */ + int rx_cnt; /* message buffer Rx fill level */ + int tx_lim; /* actual limit of bytes to Tx */ + int tx_cnt; /* number of already Tx bytes */ + char lin_master; /* node is a master node */ + int lin_baud; /* LIN baudrate */ + int lin_state; /* state */ + char id_to_send; /* there is ID to be sent */ + char data_to_send; /* there are data to be sent */ unsigned long flags; /* Flag values/ mode etc */ #define SLF_INUSE 0 /* Channel in use */ #define SLF_ERROR 1 /* Parity, etc. error */ +#define SLF_RXEVENT 2 /* Rx wake event */ +#define SLF_TXEVENT 3 /* Tx wake event */ +#define SLF_MSGEVENT 4 /* CAN message to sent */ +#define SLF_TMOUTEVENT 5 /* Timeout on received data */ - unsigned char leased; dev_t line; - pid_t pid; + struct task_struct *kwthread; + wait_queue_head_t kwt_wq; + struct hrtimer rx_timer; /* RX timeout timer */ + ktime_t rx_timer_timeout; /* RX timeout timer value */ + struct sk_buff *rec_skb; /* Socket buffer with received CAN frame */ }; static struct net_device **sllin_devs; +const unsigned char sllin_id_parity_table[] = { + 0x80,0xc0,0x40,0x00,0xc0,0x80,0x00,0x40, + 0x00,0x40,0xc0,0x80,0x40,0x00,0x80,0xc0, + 0x40,0x00,0x80,0xc0,0x00,0x40,0xc0,0x80, + 0xc0,0x80,0x00,0x40,0x80,0xc0,0x40,0x00, + 0x00,0x40,0xc0,0x80,0x40,0x00,0x80,0xc0, + 0x80,0xc0,0x40,0x00,0xc0,0x80,0x00,0x40, + 0xc0,0x80,0x00,0x40,0x80,0xc0,0x40,0x00, + 0x40,0x00,0x80,0xc0,0x00,0x40,0xc0,0x80 +}; static int sltty_change_speed(struct tty_struct *tty, unsigned speed) { @@ -113,12 +156,18 @@ static int sltty_change_speed(struct tty_struct *tty, unsigned speed) int cflag; mutex_lock(&tty->termios_mutex); + old_termios = *(tty->termios); cflag = tty->termios->c_cflag; + cflag &= ~(CBAUD | CIBAUD); + cflag |= BOTHER; + tty->termios->c_cflag = cflag; + tty_encode_baud_rate(tty, speed, speed); + if (tty->ops->set_termios) tty->ops->set_termios(tty, &old_termios); - //priv->io.speed = speed; + mutex_unlock(&tty->termios_mutex); return 0; @@ -128,92 +177,30 @@ static int sltty_change_speed(struct tty_struct *tty, unsigned speed) /* Send one completely decapsulated can_frame to the network layer */ static void sll_bump(struct sllin *sl) { -// struct sk_buff *skb; -// struct can_frame cf; -// int i, dlc_pos, tmp; -// unsigned long ultmp; -// char cmd = sl->rbuff[0]; -// -// if ((cmd != 't') && (cmd != 'T') && (cmd != 'r') && (cmd != 'R')) -// return; -// -// if (cmd & 0x20) /* tiny chars 'r' 't' => standard frame format */ -// dlc_pos = 4; /* dlc position tiiid */ -// else -// dlc_pos = 9; /* dlc position Tiiiiiiiid */ -// -// if (!((sl->rbuff[dlc_pos] >= '0') && (sl->rbuff[dlc_pos] < '9'))) -// return; -// -// cf.can_dlc = sl->rbuff[dlc_pos] - '0'; /* get can_dlc from ASCII val */ -// -// sl->rbuff[dlc_pos] = 0; /* terminate can_id string */ -// -// if (strict_strtoul(sl->rbuff+1, 16, &ultmp)) -// return; -// -// cf.can_id = ultmp; -// -// if (!(cmd & 0x20)) /* NO tiny chars => extended frame format */ -// cf.can_id |= CAN_EFF_FLAG; -// -// if ((cmd | 0x20) == 'r') /* RTR frame */ -// cf.can_id |= CAN_RTR_FLAG; -// -// *(u64 *) (&cf.data) = 0; /* clear payload */ -// -// for (i = 0, dlc_pos++; i < cf.can_dlc; i++) { -// -// tmp = asc2nibble(sl->rbuff[dlc_pos++]); -// if (tmp > 0x0F) -// return; -// cf.data[i] = (tmp << 4); -// tmp = asc2nibble(sl->rbuff[dlc_pos++]); -// if (tmp > 0x0F) -// return; -// cf.data[i] |= tmp; -// } -// -// -// skb = dev_alloc_skb(sizeof(struct can_frame)); -// if (!skb) -// return; -// -// skb->dev = sl->dev; -// skb->protocol = htons(ETH_P_CAN); -// skb->pkt_type = PACKET_BROADCAST; -// skb->ip_summed = CHECKSUM_UNNECESSARY; -// memcpy(skb_put(skb, sizeof(struct can_frame)), -// &cf, sizeof(struct can_frame)); -// netif_rx(skb); -// -// sl->dev->stats.rx_packets++; -// sl->dev->stats.rx_bytes += cf.can_dlc; -} + struct sk_buff *skb; + struct can_frame cf; -/* parse tty input stream */ -static void sllin_unesc(struct sllin *sl, unsigned char s) -{ + cf.can_id = sl->rx_buff[SLLIN_BUFF_ID] & SLLIN_ID_MASK; + cf.can_dlc = sl->rx_cnt - SLLIN_BUFF_DATA; + memcpy(&cf.data, sl->rx_buff + SLLIN_BUFF_DATA, cf.can_dlc); - if ((s == '\r') || (s == '\a')) { /* CR or BEL ends the pdu */ - if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && - (sl->rcount > 4)) { - sll_bump(sl); - } - sl->rcount = 0; - } else { - if (!test_bit(SLF_ERROR, &sl->flags)) { - if (sl->rcount < SLC_MTU) { - sl->rbuff[sl->rcount++] = s; - return; - } else { - sl->dev->stats.rx_over_errors++; - set_bit(SLF_ERROR, &sl->flags); - } - } - } + skb = dev_alloc_skb(sizeof(struct can_frame)); + if (!skb) + return; + + skb->dev = sl->dev; + skb->protocol = htons(ETH_P_CAN); + skb->pkt_type = PACKET_BROADCAST; + skb->ip_summed = CHECKSUM_UNNECESSARY; + memcpy(skb_put(skb, sizeof(struct can_frame)), + &cf, sizeof(struct can_frame)); + netif_rx(skb); + + sl->dev->stats.rx_packets++; + sl->dev->stats.rx_bytes += cf.can_dlc; } + /************************************************************************ * STANDARD SLLIN ENCAPSULATION * ************************************************************************/ @@ -221,49 +208,49 @@ static void sllin_unesc(struct sllin *sl, unsigned char s) /* Convert particular CAN frame into LIN frame and send it to TTY queue. */ static void sll_encaps(struct sllin *sl, struct can_frame *cf) { - int actual, idx, i; - char lframe[16] = {0x00, 0x55}; /* Fake break, Sync byte */ - struct tty_struct *tty = sl->tty; - - pr_debug("sllin: %s() invoked\n", __FUNCTION__); - - /* We do care only about SFF frames */ - if (cf->can_id & CAN_EFF_FLAG) - return; - - /* Send only header */ - if (cf->can_id & CAN_RTR_FLAG) { - pr_debug("sllin: RTR CAN frame\n", __FUNCTION__); - lframe[2] = (u8)cf->can_id; /* Get one byte LIN ID */ - - sltty_change_speed(tty, 1200); - tty->ops->write(tty, &lframe[0], 1); - sltty_change_speed(tty, 2400); - tty->ops->write(tty, &lframe[1], 1); - tty->ops->write(tty, &lframe[2], 1); - } else { - pr_debug("sllin: non-RTR CAN frame\n", __FUNCTION__); - /* idx = strlen(sl->xbuff); - - for (i = 0; i < cf->can_dlc; i++) - sprintf(&sl->xbuff[idx + 2*i], "%02X", cf->data[i]); - - * Order of next two lines is *very* important. - * When we are sending a little amount of data, - * the transfer may be completed inside the ops->write() - * routine, because it's running with interrupts enabled. - * In this case we *never* got WRITE_WAKEUP event, - * if we did not request it before write operation. - * 14 Oct 1994 Dmitry Gorodchanin. - - set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); - actual = sl->tty->ops->write(sl->tty, sl->xbuff, strlen(sl->xbuff)); - sl->xleft = strlen(sl->xbuff) - actual; - sl->xhead = sl->xbuff + actual; - sl->dev->stats.tx_bytes += cf->can_dlc; - */ - } - +// int actual, idx, i; +// char lframe[16] = {0x00, 0x55}; /* Fake break, Sync byte */ +// struct tty_struct *tty = sl->tty; +// +// pr_debug("sllin: %s() invoked\n", __FUNCTION__); +// +// /* We do care only about SFF frames */ +// if (cf->can_id & CAN_EFF_FLAG) +// return; +// +// /* Send only header */ +// if (cf->can_id & CAN_RTR_FLAG) { +// pr_debug("sllin: %s() RTR CAN frame\n", __FUNCTION__); +// lframe[2] = (u8)cf->can_id; /* Get one byte LIN ID */ +// +// sltty_change_speed(tty, sl->lin_baud * 2 / 3); +// tty->ops->write(tty, &lframe[0], 1); +// sltty_change_speed(tty, sl->lin_baud); +// tty->ops->write(tty, &lframe[1], 1); +// tty->ops->write(tty, &lframe[2], 1); +// } else { +// pr_debug("sllin: %s() non-RTR CAN frame\n", __FUNCTION__); +// /* idx = strlen(sl->xbuff); +// +// for (i = 0; i < cf->can_dlc; i++) +// sprintf(&sl->xbuff[idx + 2*i], "%02X", cf->data[i]); +// +// * Order of next two lines is *very* important. +// * When we are sending a little amount of data, +// * the transfer may be completed inside the ops->write() +// * routine, because it's running with interrupts enabled. +// * In this case we *never* got WRITE_WAKEUP event, +// * if we did not request it before write operation. +// * 14 Oct 1994 Dmitry Gorodchanin. +// +// set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); +// actual = sl->tty->ops->write(sl->tty, sl->xbuff, strlen(sl->xbuff)); +// sl->xleft = strlen(sl->xbuff) - actual; +// sl->xhead = sl->xbuff + actual; +// sl->dev->stats.tx_bytes += cf->can_dlc; +// */ +// } +// } /* @@ -273,24 +260,34 @@ static void sll_encaps(struct sllin *sl, struct can_frame *cf) static void sllin_write_wakeup(struct tty_struct *tty) { int actual; + int remains; struct sllin *sl = (struct sllin *) tty->disc_data; /* First make sure we're connected. */ if (!sl || sl->magic != SLLIN_MAGIC || !netif_running(sl->dev)) return; - if (sl->xleft <= 0) { - /* Now serial buffer is almost free & we can start - * transmission of another packet */ - sl->dev->stats.tx_packets++; - clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); - netif_wake_queue(sl->dev); - return; + if (sl->lin_state != SLSTATE_BREAK_SENT) + remains = sl->tx_lim - sl->tx_cnt; + else + remains = SLLIN_BUFF_BREAK + 1 - sl->tx_cnt; + + if (remains > 0) { + actual = tty->ops->write(tty, sl->tx_buff + sl->tx_cnt, sl->tx_cnt - sl->tx_lim); + sl->tx_cnt += actual; + + if (sl->tx_cnt < sl->tx_lim) { + printk(KERN_INFO "sllin_write_wakeup sent %d, remains %d, waiting\n", + sl->tx_cnt, sl->tx_lim - sl->tx_cnt); + return; + } } - actual = tty->ops->write(tty, sl->xhead, sl->xleft); - sl->xleft -= actual; - sl->xhead += actual; + clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + set_bit(SLF_TXEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + + printk(KERN_INFO "sllin_write_wakeup sent %d, wakeup\n", sl->tx_cnt); } /* Send a can_frame to a TTY queue. */ @@ -299,24 +296,28 @@ static netdev_tx_t sll_xmit(struct sk_buff *skb, struct net_device *dev) struct sllin *sl = netdev_priv(dev); if (skb->len != sizeof(struct can_frame)) - goto out; + goto err_out; spin_lock(&sl->lock); if (!netif_running(dev)) { spin_unlock(&sl->lock); printk(KERN_WARNING "%s: xmit: iface is down\n", dev->name); - goto out; + goto err_out; } if (sl->tty == NULL) { spin_unlock(&sl->lock); - goto out; + goto err_out; } netif_stop_queue(sl->dev); - sll_encaps(sl, (struct can_frame *) skb->data); /* encaps & send */ + + sl->rec_skb = skb; + set_bit(SLF_MSGEVENT, &sl->flags); + wake_up(&sl->kwt_wq); spin_unlock(&sl->lock); + return NETDEV_TX_OK; -out: +err_out: kfree_skb(skb); return NETDEV_TX_OK; } @@ -337,8 +338,8 @@ static int sll_close(struct net_device *dev) clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); } netif_stop_queue(dev); - sl->rcount = 0; - sl->xleft = 0; + sl->rx_expect = 0; + sl->tx_lim = 0; spin_unlock_bh(&sl->lock); return 0; @@ -408,6 +409,8 @@ static void sllin_receive_buf(struct tty_struct *tty, { struct sllin *sl = (struct sllin *) tty->disc_data; + printk(KERN_INFO "sllin_receive_buf invoked\n"); + if (!sl || sl->magic != SLLIN_MAGIC || !netif_running(sl->dev)) return; @@ -416,13 +419,348 @@ static void sllin_receive_buf(struct tty_struct *tty, if (fp && *fp++) { if (!test_and_set_bit(SLF_ERROR, &sl->flags)) sl->dev->stats.rx_errors++; + printk(KERN_INFO "sllin_receive_buf char 0x%02x ignored " + "due marker 0x%02x, flags 0x%lx\n", + *cp, *(fp-1), sl->flags); cp++; continue; } - sllin_unesc(sl, *cp++); + + if (sl->rx_cnt < SLLIN_BUFF_LEN) { +#ifndef BREAK_BY_BAUD + /* We didn't receive Break character */ + if ((sl->rx_cnt == SLLIN_BUFF_BREAK) && (*cp == 0x55)) { + sl->rx_buff[sl->rx_cnt++] = 0x00; + } +#endif + printk(KERN_INFO "LIN_RX[%d]: 0x%02x\n", sl->rx_cnt, *cp); + sl->rx_buff[sl->rx_cnt++] = *cp++; + } + } + + if (sl->rx_cnt >= sl->rx_expect) { + set_bit(SLF_RXEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + printk(KERN_INFO "sllin_receive_buf count %d, wakeup\n", sl->rx_cnt); + } else { + printk(KERN_INFO "sllin_receive_buf count %d, waiting\n", sl->rx_cnt); } } +/***************************************** + * sllin message helper routines + *****************************************/ + +int sllin_setup_msg(struct sllin *sl, int mode, int id, + unsigned char *data, int len) +{ + if (id > SLLIN_ID_MASK) + return -1; + + sl->rx_cnt = 0; + sl->tx_cnt = 0; + sl->rx_expect = 0; + sl->rx_lim = SLLIN_BUFF_LEN; + + sl->tx_buff[SLLIN_BUFF_BREAK] = 0; + sl->tx_buff[SLLIN_BUFF_SYNC] = 0x55; + sl->tx_buff[SLLIN_BUFF_ID] = id | sllin_id_parity_table[id]; + sl->tx_lim = SLLIN_BUFF_DATA; + + if ((data != NULL) && len) { + int i; + unsigned csum = 0; + + sl->tx_lim += len; + memcpy(sl->tx_buff + SLLIN_BUFF_DATA, data, len); + /* compute data parity there */ + for (i = SLLIN_BUFF_DATA; i < sl->tx_lim; i++) { + csum += sl->tx_buff[i]; + if (csum > 255) + csum -= 255; + } + + sl->tx_buff[sl->tx_lim++] = csum; + } + if (len != 0) + sl->rx_lim = SLLIN_BUFF_DATA + len + 1; + + return 0; +} + + +int sllin_send_tx_buff(struct sllin *sl) +{ + struct tty_struct *tty = sl->tty; + int remains; + int res; + +#ifdef BREAK_BY_BAUD + if (sl->lin_state != SLSTATE_BREAK_SENT) + remains = sl->tx_lim - sl->tx_cnt; + else + remains = 1; +#else + remains = sl->tx_lim - sl->tx_cnt; +#endif + + res = tty->ops->write(tty, sl->tx_buff + sl->tx_cnt, remains); + if (res < 0) + return -1; + + remains -= res; + sl->tx_cnt += res; + + if (remains > 0) { + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + res = tty->ops->write(tty, sl->tx_buff + sl->tx_cnt, remains); + if (res < 0) { + clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + return -1; + } + + remains -= res; + sl->tx_cnt += res; + } + + printk(KERN_INFO "sllin_send_tx_buff sent %d, remains %d\n", + sl->tx_cnt, remains); + + return 0; +} + +#ifdef BREAK_BY_BAUD +int sllin_send_break(struct sllin *sl) +{ + struct tty_struct *tty = sl->tty; + unsigned long break_baud; + int res; + + break_baud = ((sl->lin_baud * 2) / 3); + sltty_change_speed(tty, break_baud); + + tty->ops->flush_buffer(tty); + sl->rx_cnt = SLLIN_BUFF_BREAK; + + sl->rx_expect = SLLIN_BUFF_BREAK + 1; + sl->lin_state = SLSTATE_BREAK_SENT; + + res = sllin_send_tx_buff(sl); + if (res < 0) { + sl->lin_state = SLSTATE_IDLE; + return res; + } + + return 0; +} +#else /* BREAK_BY_BAUD */ + +int sllin_send_break(struct sllin *sl) +{ + struct tty_struct *tty = sl->tty; + unsigned long break_baud; + unsigned long flags; + int retval; + + sl->rx_cnt = SLLIN_BUFF_BREAK; + sl->rx_expect = SLLIN_BUFF_BREAK + 1; + sl->lin_state = SLSTATE_BREAK_SENT; + + /* Do the break ourselves; Inspired by + http://lxr.linux.no/#linux+v3.1.2/drivers/tty/tty_io.c#L2452 */ + retval = tty->ops->break_ctl(tty, -1); + if (retval) + return retval; + + //udelay(712); + usleep_range(650, 750); + + retval = tty->ops->break_ctl(tty, 0); + usleep_range(50, 100); + + tty->ops->flush_buffer(tty); + + sl->tx_cnt = SLLIN_BUFF_SYNC; + + printk(KERN_INFO "sllin: Break sent.\n"); + set_bit(SLF_RXEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + + return 0; +} +#endif /* BREAK_BY_BAUD */ + + +static enum hrtimer_restart sllin_rx_timeout_handler(struct hrtimer *hrtimer) +{ + struct sllin *sl = container_of(hrtimer, struct sllin, rx_timer); + + set_bit(SLF_TMOUTEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + + return HRTIMER_NORESTART; +} + + +/***************************************** + * sllin_kwthread - kernel worker thread + *****************************************/ + +int sllin_kwthread(void *ptr) +{ + struct sllin *sl = (struct sllin *)ptr; + struct tty_struct *tty = sl->tty; + struct sched_param schparam = { .sched_priority = 40 }; + int res; + struct can_frame *cf; + + printk(KERN_INFO "sllin: sllin_kwthread started.\n"); + sched_setscheduler(current, SCHED_FIFO, &schparam); + + clear_bit(SLF_ERROR, &sl->flags); + sltty_change_speed(tty, sl->lin_baud); + + while (!kthread_should_stop()) { + if ((sl->lin_state == SLSTATE_IDLE) && sl->lin_master && + sl->id_to_send) { + if(sllin_send_break(sl) < 0) { + /* error processing */ + } + } + + wait_event_killable(sl->kwt_wq, kthread_should_stop() || + test_bit(SLF_RXEVENT, &sl->flags) || + test_bit(SLF_TXEVENT, &sl->flags) || + test_bit(SLF_TMOUTEVENT, &sl->flags) || + ((sl->lin_state == SLSTATE_IDLE) && test_bit(SLF_MSGEVENT, &sl->flags))); + + if (test_and_clear_bit(SLF_RXEVENT, &sl->flags)) { + printk(KERN_INFO "sllin_kthread RXEVENT \n"); + } + + if (test_and_clear_bit(SLF_TXEVENT, &sl->flags)) { + printk(KERN_INFO "sllin_kthread TXEVENT \n"); + } + + if (test_and_clear_bit(SLF_TMOUTEVENT, &sl->flags)) { + printk(KERN_INFO "sllin_kthread TMOUTEVENT \n"); + sl->rx_cnt = 0; + sl->rx_expect = 0; + sl->rx_lim = sl->lin_master ? 0 : SLLIN_BUFF_LEN; + sl->tx_cnt = 0; + sl->tx_lim = 0; + sl->id_to_send = false; + sl->data_to_send = false; + + sl->lin_state = SLSTATE_IDLE; + } + + if ((sl->lin_state == SLSTATE_IDLE) && test_bit(SLF_MSGEVENT, &sl->flags)) { + cf = (struct can_frame *)sl->rec_skb->data; + + /* We do care only about SFF frames */ + if (cf->can_id & CAN_EFF_FLAG) + goto release_skb; + + if (cf->can_id & CAN_RTR_FLAG) { + printk(KERN_INFO "%s: RTR CAN frame, ID = %x\n", + __FUNCTION__, cf->can_id & CAN_SFF_MASK); + if (sllin_setup_msg(sl, 0, + cf->can_id & CAN_SFF_MASK, NULL, 0) != -1) { + sl->id_to_send = true; + sl->data_to_send = false; + } + } else { + printk(KERN_INFO "%s: NON-RTR CAN frame, ID = %x\n", + __FUNCTION__, (int)cf->can_id & CAN_SFF_MASK); + + if (sllin_setup_msg(sl, 0, cf->can_id & CAN_SFF_MASK, + cf->data, cf->can_dlc) != -1) { + sl->id_to_send = true; + sl->data_to_send = true; + } + } + + release_skb: + clear_bit(SLF_MSGEVENT, &sl->flags); + kfree_skb(sl->rec_skb); + netif_wake_queue(sl->dev); + } + + switch (sl->lin_state) { + case SLSTATE_BREAK_SENT: +#ifdef BREAK_BY_BAUD + if (sl->rx_cnt <= SLLIN_BUFF_BREAK) + continue; + + res = sltty_change_speed(tty, sl->lin_baud); +#endif + + sl->lin_state = SLSTATE_ID_SENT; + sllin_send_tx_buff(sl); + break; + + case SLSTATE_ID_SENT: + sl->id_to_send = false; + if (sl->data_to_send) { + sllin_send_tx_buff(sl); + sl->lin_state = SLSTATE_RESPONSE_SENT; + sl->rx_expect = sl->tx_lim; + goto slstate_response_sent; + } else { + sl->rx_expect = SLLIN_BUFF_DATA + 2; + sl->lin_state = SLSTATE_RESPONSE_WAIT; + /* If we don't receive anything, timer will "unblock" us */ + hrtimer_start(&sl->rx_timer, + ktime_add(ktime_get(), sl->rx_timer_timeout), + HRTIMER_MODE_ABS); + goto slstate_response_wait; + } + break; + + case SLSTATE_RESPONSE_WAIT: + slstate_response_wait: + if (sl->rx_cnt < sl->rx_expect) + continue; + + hrtimer_cancel(&sl->rx_timer); + printk(KERN_INFO "sllin: response received ID %d len %d\n", + sl->rx_buff[SLLIN_BUFF_ID], sl->rx_cnt - SLLIN_BUFF_DATA - 1); + // check checksum in sl->rx_buff + // send CAN non-RTR frame with data + printk(KERN_INFO "sllin: sending NON-RTR CAN frame with LIN payload."); + sll_bump(sl); //send packet to the network layer + sl->id_to_send = false; + sl->lin_state = SLSTATE_IDLE; + break; + + case SLSTATE_RESPONSE_SENT: + slstate_response_sent: + if (sl->rx_cnt < sl->tx_lim) + continue; + + printk(KERN_INFO "sllin: response sent ID %d len %d\n", + sl->rx_buff[SLLIN_BUFF_ID], sl->rx_cnt - SLLIN_BUFF_DATA - 1); + + sl->id_to_send = false; + sl->lin_state = SLSTATE_IDLE; + break; + } + + + + + /* sl->dev->stats.tx_packets++; send frames statistic */ + /* netif_wake_queue(sl->dev); allow next Tx packet arrival */ + } + + hrtimer_cancel(&sl->rx_timer); + printk(KERN_INFO "sllin: sllin_kwthread stopped.\n"); + + return 0; +} + + /************************************ * sllin_open helper routines. ************************************/ @@ -440,7 +778,7 @@ static void sll_sync(void) break; sl = netdev_priv(dev); - if (sl->tty || sl->leased) + if (sl->tty) continue; if (dev->flags & IFF_UP) dev_close(dev); @@ -545,27 +883,55 @@ static int sllin_open(struct tty_struct *tty) sl->tty = tty; tty->disc_data = sl; sl->line = tty_devnum(tty); - sl->pid = current->pid; if (!test_bit(SLF_INUSE, &sl->flags)) { /* Perform the low-level SLLIN initialization. */ - sl->rcount = 0; - sl->xleft = 0; - + sl->lin_master = true; + + sl->rx_cnt = 0; + sl->rx_expect = 0; + sl->rx_lim = sl->lin_master ? 0 : SLLIN_BUFF_LEN; + sl->tx_cnt = 0; + sl->tx_lim = 0; + sl->id_to_send = false; + sl->data_to_send = false; + + sl->lin_baud = 19200; + + sl->lin_state = SLSTATE_IDLE; + +#define SAMPLES_PER_CHAR 10 +#define CHARS_TO_TIMEOUT 12 + hrtimer_init(&sl->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + sl->rx_timer.function = sllin_rx_timeout_handler; + /* timeval_to_ktime(msg_head->ival1); */ + sl->rx_timer_timeout = ns_to_ktime( + (1000000000 / sl->lin_baud) * + SAMPLES_PER_CHAR * CHARS_TO_TIMEOUT); + set_bit(SLF_INUSE, &sl->flags); + init_waitqueue_head(&sl->kwt_wq); + sl->kwthread = kthread_run(sllin_kwthread, sl, "sllin"); + if (sl->kwthread == NULL) + goto err_free_chan; + err = register_netdevice(sl->dev); if (err) - goto err_free_chan; + goto err_free_chan_and_thread; } /* Done. We have linked the TTY line to a channel. */ rtnl_unlock(); - tty->receive_room = 65536; /* We don't flow control */ + tty->receive_room = SLLIN_BUFF_LEN * 40; /* We don't flow control */ /* TTY layer expects 0 on success */ return 0; +err_free_chan_and_thread: + kthread_stop(sl->kwthread); + sl->kwthread = NULL; + err_free_chan: sl->tty = NULL; tty->disc_data = NULL; @@ -594,10 +960,11 @@ static void sllin_close(struct tty_struct *tty) if (!sl || sl->magic != SLLIN_MAGIC || sl->tty != tty) return; + kthread_stop(sl->kwthread); + sl->kwthread = NULL; + tty->disc_data = NULL; sl->tty = NULL; - if (!sl->leased) - sl->line = 0; /* Flush network side */ unregister_netdev(sl->dev);