]> rtime.felk.cvut.cz Git - linux-lin.git/blobdiff - sllin/sllin.c
sllin: Added module parameters.
[linux-lin.git] / sllin / sllin.c
index 7388bb60b42cada46067d2f6ca37cb98fb117b0e..459ae9f58eabd8b8ee1706e7aa5d551e9413132d 100644 (file)
@@ -1,4 +1,4 @@
-/*
+/* 
  * sllin.c - serial line LIN interface driver (using tty line discipline)
  *
  * This file is derived from drivers/net/can/slcan.c
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
  * DAMAGE.
  *
- * Send feedback to <socketcan-users@lists.berlios.de>
- *
+ * Idea:       Oliver Hartkopp <oliver.hartkopp@volkswagen.de> 
+ * Copyright:  (c) 2011 Czech Technical University in Prague
+ *             (c) 2011 Volkswagen Group Research
+ * Authors:    Pavel Pisa <pisa@cmp.felk.cvut.cz>
+ *             Rostislav Lisovy <lisovy@kormus.cz>
+ *             Michal Sojka <sojkam1@fel.cvut.cz>
+ * Funded by:  Volkswagen Group Research
  */
 
 #define DEBUG          1 /* Enables pr_debug() printouts */
@@ -70,11 +75,19 @@ static __initdata const char banner[] =
 MODULE_ALIAS_LDISC(N_SLLIN);
 MODULE_DESCRIPTION("serial line LIN interface");
 MODULE_LICENSE("GPL");
-MODULE_AUTHOR("");
+MODULE_AUTHOR("Pavel Pisa <pisa@cmp.felk.cvut.cz>");
 
 #define SLLIN_MAGIC            0x53CA
 /* #define BREAK_BY_BAUD */
 
+static int master = true;
+static int baudrate = 0; /* Use LIN_DEFAULT_BAUDRATE when not set */
+
+module_param(master, bool, 0);
+MODULE_PARM_DESC(master, "LIN interface is Master device");
+module_param(baudrate, int, 0);
+MODULE_PARM_DESC(baudrate, "Baudrate of LIN interface");
+
 static int maxdev = 10;                /* MAX number of SLLIN channels;
                                   This can be overridden with
                                   insmod sllin.ko maxdev=nnn   */
@@ -91,7 +104,7 @@ 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,
@@ -188,10 +201,16 @@ static int sltty_change_speed(struct tty_struct *tty, unsigned speed)
        mutex_lock(&tty->termios_mutex);
 
        old_termios = *(tty->termios);
-       cflag = tty->termios->c_cflag;
+
+       cflag = CS8 | CREAD | CLOCAL | HUPCL;
        cflag &= ~(CBAUD | CIBAUD);
        cflag |= BOTHER;
        tty->termios->c_cflag = cflag;
+       tty->termios->c_oflag = 0;
+       tty->termios->c_lflag = 0;
+
+       /* Enable interrupt when UART-Break or Framing error received */
+       tty->termios->c_iflag = BRKINT | INPCK;
 
        tty_encode_baud_rate(tty, speed, speed);
 
@@ -203,7 +222,6 @@ static int sltty_change_speed(struct tty_struct *tty, unsigned speed)
        return 0;
 }
 
-
 /* Send one can_frame to the network layer */
 static void sllin_send_canfr(struct sllin *sl, canid_t id, char *data, int len)
 {
@@ -415,13 +433,21 @@ 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++;
-                       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->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);
+
+                               if (sl->lin_master == true) {
+                                       wake_up(&sl->kwt_wq);
+                                       return;
+                               }
+
+                               cp++;
+                               continue;
+                       }
                }
 
                if (sl->rx_cnt < SLLIN_BUFF_LEN) {
@@ -465,6 +491,10 @@ 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 |
@@ -561,6 +591,16 @@ 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)
 {
@@ -752,6 +792,7 @@ 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)));
@@ -760,19 +801,30 @@ 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;
                }
@@ -935,6 +987,7 @@ 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);
@@ -1076,17 +1129,12 @@ static int sllin_open(struct tty_struct *tty)
 
        if (!test_bit(SLF_INUSE, &sl->flags)) {
                /* Perform the low-level SLLIN initialization. */
-               sl->lin_master = true;
+               sl->lin_master = master;
 
-               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;
+               sl->lin_baud = (baudrate == 0) ? LIN_DEFAULT_BAUDRATE : baudrate;
+               pr_debug("sllin: Baudrate set to %u\n", sl->lin_baud);
 
                sl->lin_state = SLSTATE_IDLE;