]> rtime.felk.cvut.cz Git - linux-lin.git/blobdiff - sllin/sllin.c
sllin: Add first support for LIN slave task on slave node
[linux-lin.git] / sllin / sllin.c
index e8aca083e6f99f9a27f116b707248fcf004d2660..3e020b1a07ce93d2f1856fa1fdcc0e992d3d4406 100644 (file)
@@ -113,6 +113,7 @@ enum slstate {
        SLSTATE_RESPONSE_WAIT_BUS, /* Wait for response from LIN bus
                                only (CAN frames from network stack
                                are not processed in this moment) */
+       SLSTATE_ID_RECEIVED,
        SLSTATE_RESPONSE_SENT,
 };
 
@@ -670,6 +671,23 @@ static int sllin_rx_validate(struct sllin *sl)
        return 0;
 }
 
+static void sllin_slave_finish_rx_msg(struct sllin *sl)
+{
+       if (sllin_rx_validate(sl) == -1) {
+               netdev_dbg(sl->dev, "sllin: RX validation failed.\n");
+               sllin_report_error(sl, LIN_ERR_CHECKSUM);
+       } else {
+               /* Send CAN non-RTR frame with data */
+               netdev_dbg(sl->dev, "sllin: sending NON-RTR CAN frame with LIN payload.");
+               sll_bump(sl); /* send packet to the network layer */
+       }
+       /* Prepare for reception of new header */
+       sl->rx_cnt = 0;
+       sl->rx_expect = SLLIN_BUFF_ID + 1;
+       sl->rx_len_unknown = false; /* We do know exact length of the header */
+       sl->header_received = false;
+}
+
 static void sllin_slave_receive_buf(struct tty_struct *tty,
                              const unsigned char *cp, char *fp, int count)
 {
@@ -681,6 +699,20 @@ static void sllin_slave_receive_buf(struct tty_struct *tty,
        /* Read the characters out of the buffer */
        while (count--) {
                if (fp && *fp++) {
+                       /*
+                        * If we don't know the length of the current message
+                        * we received the break of the next message.
+                        * Evaluate the previous one before continuing
+                        */
+                       if (sl->rx_len_unknown == true)
+                       {
+                               hrtimer_cancel(&sl->rx_timer);
+                               sllin_slave_finish_rx_msg(sl);
+
+                               set_bit(SLF_RXEVENT, &sl->flags);
+                               wake_up(&sl->kwt_wq);
+                       }
+
                        netdev_dbg(sl->dev, "sllin_slave_receive_buf char 0x%02x ignored "
                                "due marker 0x%02x, flags 0x%lx\n",
                                *cp, *(fp-1), sl->flags);
@@ -724,10 +756,13 @@ static void sllin_slave_receive_buf(struct tty_struct *tty,
 
                        spin_lock_irqsave(&sl->linfr_lock, flags);
 
+                       sl->lin_state = SLSTATE_ID_RECEIVED;
                        /* Is the length of data set in frame cache? */
                        if (sce->frame_fl & LIN_CACHE_RESPONSE) {
                                sl->rx_expect += sce->dlc + 1; /* + checksum */
                                sl->rx_len_unknown = false;
+                               set_bit(SLF_MSGEVENT, &sl->flags);
+                               wake_up(&sl->kwt_wq);
                        } else {
                                sl->rx_expect += SLLIN_DATA_MAX + 1; /* + checksum */
                                sl->rx_len_unknown = true;
@@ -736,25 +771,25 @@ static void sllin_slave_receive_buf(struct tty_struct *tty,
 
                        sl->header_received = true;
 
+                       hrtimer_start(&sl->rx_timer,
+                               ktime_add(ktime_get(), sl->rx_timer_timeout),
+                               HRTIMER_MODE_ABS);
                        sll_send_rtr(sl);
                        continue;
                }
 
                /* Response received */
                if ((sl->header_received == true) &&
-                       ((sl->rx_cnt >= sl->rx_expect) ||
-                       ((sl->rx_len_unknown == true) && (count == 0)))) {
+                       ((sl->rx_cnt >= sl->rx_expect))) {
 
-                       sll_bump(sl);
+                       hrtimer_cancel(&sl->rx_timer);
                        netdev_dbg(sl->dev, "Received LIN header & LIN response. "
                                        "rx_cnt = %u, rx_expect = %u\n", sl->rx_cnt,
                                        sl->rx_expect);
+                       sllin_slave_finish_rx_msg(sl);
 
-                       /* Prepare for reception of new header */
-                       sl->rx_cnt = 0;
-                       sl->rx_expect = SLLIN_BUFF_ID + 1;
-                       sl->rx_len_unknown = false; /* We do know exact length of the header */
-                       sl->header_received = false;
+                       set_bit(SLF_RXEVENT, &sl->flags);
+                       wake_up(&sl->kwt_wq);
                }
        }
 }
@@ -905,8 +940,13 @@ static enum hrtimer_restart sllin_rx_timeout_handler(struct hrtimer *hrtimer)
 {
        struct sllin *sl = container_of(hrtimer, struct sllin, rx_timer);
 
-       sllin_report_error(sl, LIN_ERR_RX_TIMEOUT);
-       set_bit(SLF_TMOUTEVENT, &sl->flags);
+       if (sl->lin_master) {
+               sllin_report_error(sl, LIN_ERR_RX_TIMEOUT);
+               set_bit(SLF_TMOUTEVENT, &sl->flags);
+       } else {
+               sllin_slave_finish_rx_msg(sl);
+               set_bit(SLF_RXEVENT, &sl->flags);
+       }
        wake_up(&sl->kwt_wq);
 
        return HRTIMER_NORESTART;
@@ -922,7 +962,9 @@ static int sllin_kwthread(void *ptr)
        struct tty_struct *tty = sl->tty;
        struct sched_param schparam = { .sched_priority = 40 };
        int tx_bytes = 0; /* Used for Network statistics */
-
+       unsigned long flags;
+       int lin_id;
+       struct sllin_conf_entry *sce;
 
        netdev_dbg(sl->dev, "sllin_kwthread started.\n");
        sched_setscheduler(current, SCHED_FIFO, &schparam);
@@ -950,7 +992,8 @@ static int sllin_kwthread(void *ptr)
                        test_bit(SLF_TMOUTEVENT, &sl->flags) ||
                        test_bit(SLF_ERROR, &sl->flags) ||
                        (((sl->lin_state == SLSTATE_IDLE) ||
-                               (sl->lin_state == SLSTATE_RESPONSE_WAIT))
+                               (sl->lin_state == SLSTATE_RESPONSE_WAIT) ||
+                               (sl->lin_state == SLSTATE_ID_RECEIVED))
                                && test_bit(SLF_MSGEVENT, &sl->flags)));
 
                if (test_and_clear_bit(SLF_RXEVENT, &sl->flags)) {
@@ -994,7 +1037,6 @@ static int sllin_kwthread(void *ptr)
 
                        /* SFF RTR CAN frame -> LIN header */
                        if (cf->can_id & CAN_RTR_FLAG) {
-                               unsigned long flags;
                                struct sllin_conf_entry *sce;
 
                                netdev_dbg(sl->dev, "%s: RTR SFF CAN frame, ID = %x\n",
@@ -1143,6 +1185,56 @@ slstate_response_wait:
                        sl->lin_state = SLSTATE_IDLE;
                        break;
 
+               case SLSTATE_ID_RECEIVED:
+                       lin_id = sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK;
+                       sce = &sl->linfr_cache[lin_id];
+                       spin_lock_irqsave(&sl->linfr_lock, flags);
+
+                       if ((sce->frame_fl & LIN_CACHE_RESPONSE)
+                                       && (sce->dlc > 0)
+                                       && (test_bit(SLF_MSGEVENT, &sl->flags))) {
+                               int mode;
+
+                               netdev_dbg(sl->dev, "Sending LIN response from linfr_cache\n");
+
+                               lin_data = sce->data;
+                               lin_dlc = sce->dlc;
+                               if (lin_dlc > SLLIN_DATA_MAX)
+                                       lin_dlc = SLLIN_DATA_MAX;
+                               memcpy(lin_data_buff, lin_data, lin_dlc);
+                               lin_data = lin_data_buff;
+                               tx_bytes = lin_dlc;
+
+                               mode = SLLIN_STPMSG_RESPONLY;
+                               if (sl->rx_buff[SLLIN_BUFF_ID] & LIN_CHECKSUM_EXTENDED)
+                                       mode |= SLLIN_STPMSG_CHCKSUM_ENH;
+
+                               if (sllin_setup_msg(sl, mode, lin_id & LIN_ID_MASK,
+                                       lin_data, lin_dlc) != -1) {
+
+                                       sl->rx_expect = sl->tx_lim;
+                                       sl->data_to_send = true;
+                                       sl->dev->stats.tx_packets++;
+                                       sl->dev->stats.tx_bytes += tx_bytes;
+                                       sl->resp_len_known = true;
+
+                                       if (!sl->lin_master) {
+                                               sl->tx_cnt = SLLIN_BUFF_DATA;
+                                       }
+                                       sllin_send_tx_buff(sl);
+                               }
+
+                               clear_bit(SLF_MSGEVENT, &sl->flags);
+                               kfree_skb(sl->tx_req_skb);
+                               netif_wake_queue(sl->dev);
+                               hrtimer_start(&sl->rx_timer,
+                                       ktime_add(ktime_get(), sl->rx_timer_timeout),
+                                       HRTIMER_MODE_ABS);
+                       }
+                       spin_unlock_irqrestore(&sl->linfr_lock, flags);
+                       sl->lin_state = SLSTATE_IDLE;
+                       break;
+
                case SLSTATE_RESPONSE_SENT:
 slstate_response_sent:
                        if (sl->rx_cnt < sl->tx_lim)