sllin: Improved handling of UART errors.

diff --git a/sllin/linux/lin_bus.h b/sllin/linux/lin_bus.h
index 467b605171a34676825e235f75a1dfabafb185a7..429b82ae1cabb06b59da76b6c34f328394d04a33 100644 (file)
--- a/sllin/linux/lin_bus.h
+++ b/sllin/linux/lin_bus.h
@@ -18,6 +18,6 @@
 
 #define LIN_ERR_RX_TIMEOUT     (1 << (LIN_CANFR_FLAGS_OFFS + 7))
 #define LIN_ERR_CHECKSUM       (1 << (LIN_CANFR_FLAGS_OFFS + 8))
-//#define LIN_ERR_FRAMING      (1 << (LIN_CANFR_FLAGS_OFFS + 9))
+#define LIN_ERR_FRAMING                (1 << (LIN_CANFR_FLAGS_OFFS + 9))
 
 #endif /* _LIN_BUS_H_ */

diff --git a/sllin/sllin.c b/sllin/sllin.c
index 92420f0e3ce0b29a4559ba8fd923cb21edc51ce1..528d746c077eb101fe1945494947727dc566d232 100644 (file)
--- a/sllin/sllin.c
+++ b/sllin/sllin.c
@@ -91,7 +91,7 @@ MODULE_PARM_DESC(maxdev, "Maximum number of sllin interfaces");
 #define SLLIN_BUFF_DATA                3
 
 #define SLLIN_SAMPLES_PER_CHAR 10
-#define SLLIN_CHARS_TO_TIMEOUT 12
+#define SLLIN_CHARS_TO_TIMEOUT 24
 
 enum slstate {
        SLSTATE_IDLE = 0,
@@ -420,15 +420,21 @@ static void sllin_receive_buf(struct tty_struct *tty,
        /* Read the characters out of the buffer */
        while (count--) {
                if (fp && *fp++) {
-                       if (!test_and_set_bit(SLF_ERROR, &sl->flags))
-                               sl->dev->stats.rx_errors++;
+                       if (sl->rx_cnt > SLLIN_BUFF_BREAK) {
+                               set_bit(SLF_ERROR, &sl->flags);
 
-                       pr_debug("sllin: sllin_receive_buf char 0x%02x ignored "
-                               "due marker 0x%02x, flags 0x%lx\n",
-                               *cp, *(fp-1), sl->flags);
+                               pr_debug("sllin: sllin_receive_buf char 0x%02x ignored "
+                                       "due marker 0x%02x, flags 0x%lx\n",
+                                       *cp, *(fp-1), sl->flags);
 
-                       cp++;
-                       continue;
+                               if (sl->lin_master == true) {
+                                       wake_up(&sl->kwt_wq);
+                                       return;
+                               }
+
+                               cp++;
+                               continue;
+                       }
                }
 
                if (sl->rx_cnt < SLLIN_BUFF_LEN) {
@@ -472,6 +478,10 @@ void sllin_report_error(struct sllin *sl, int err)
                case LIN_ERR_RX_TIMEOUT:                
                        sl->dev->stats.rx_errors++;
                        break;
+
+               case LIN_ERR_FRAMING:
+                       sl->dev->stats.rx_frame_errors++;
+                       break;
        }
 
        sllin_send_canfr(sl, 0 | CAN_EFF_FLAG |
@@ -568,6 +578,16 @@ int sllin_setup_msg(struct sllin *sl, int mode, int id,
        return 0;
 }
 
+static void sllin_reset_buffs(struct sllin *sl)
+{
+       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;
+}
 
 int sllin_send_tx_buff(struct sllin *sl)
 {
@@ -759,6 +779,7 @@ int sllin_kwthread(void *ptr)
                        test_bit(SLF_RXEVENT, &sl->flags) ||
                        test_bit(SLF_TXEVENT, &sl->flags) ||
                        test_bit(SLF_TMOUTEVENT, &sl->flags) ||
+                       test_bit(SLF_ERROR, &sl->flags) ||
                        (((sl->lin_state == SLSTATE_IDLE) ||
                                (sl->lin_state == SLSTATE_RESPONSE_WAIT))
                                && test_bit(SLF_MSGEVENT, &sl->flags)));
@@ -767,19 +788,30 @@ int sllin_kwthread(void *ptr)
                        pr_debug("sllin: sllin_kthread RXEVENT\n");
                }
 
+               if (test_and_clear_bit(SLF_ERROR, &sl->flags)) {
+                       unsigned long usleep_range_min;
+                       unsigned long usleep_range_max;
+                       hrtimer_cancel(&sl->rx_timer);
+                       pr_debug("sllin: sllin_kthread ERROR\n");
+
+                       if (sl->lin_state != SLSTATE_IDLE)
+                               sllin_report_error(sl, LIN_ERR_FRAMING);
+
+                       usleep_range_min = (1000000l * SLLIN_SAMPLES_PER_CHAR * 10) /
+                                               sl->lin_baud;
+                       usleep_range_max = usleep_range_min + 50;
+                       usleep_range(usleep_range_min, usleep_range_max);
+                       sllin_reset_buffs(sl);
+                       sl->lin_state = SLSTATE_IDLE;
+               }
+
                if (test_and_clear_bit(SLF_TXEVENT, &sl->flags)) {
                        pr_debug("sllin: sllin_kthread TXEVENT\n");
                }
 
                if (test_and_clear_bit(SLF_TMOUTEVENT, &sl->flags)) {
                        pr_debug("sllin: 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;
+                       sllin_reset_buffs(sl);
 
                        sl->lin_state = SLSTATE_IDLE;
                }
@@ -942,6 +974,7 @@ int sllin_kwthread(void *ptr)
                                if (sl->rx_cnt < sl->tx_lim)
                                        continue;
 
+                               hrtimer_cancel(&sl->rx_timer);
                                sll_bump(sl); /* send packet to the network layer */
                                pr_debug("sllin: response sent ID %d len %d\n",
                                        sl->rx_buff[SLLIN_BUFF_ID], sl->rx_cnt - SLLIN_BUFF_DATA - 1);
@@ -1085,13 +1118,7 @@ static int sllin_open(struct tty_struct *tty)
                /* Perform the low-level SLLIN initialization. */
                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;
+               sllin_reset_buffs(sl);
 
                sl->lin_baud  = 19200;