+
+ 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 > 0x3f)
+ return -1;
+
+ sl->rx_cnt = 0;
+ sl->tx_cnt = 0;
+ sl->rx_expect = 0;
+
+ 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 += 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;
+ set_bit(SLF_RXEVENT, &sl->flags);
+ wake_up(&sl->kwt_wq);
+
+ return 0;
+}
+#endif /* BREAK_BY_BAUD */
+
+/*****************************************
+ * 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;
+ unsigned char buff[8] = {0x2, 0x3, 0x4, 0x5};
+
+ 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);
+
+ //sllin_setup_msg(sl, 0, 0x01, NULL, 0);
+ sllin_setup_msg(sl, 0, 0x02, buff, 4);
+ sl->id_to_send = true;
+
+ 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));
+
+ 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");
+ }
+
+ switch (sl->lin_state) {
+ case SLSTATE_BREAK_SENT:
+ if (sl->rx_cnt <= SLLIN_BUFF_BREAK)
+ continue;
+#ifdef BREAK_BY_BAUD
+ 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;
+ sl->lin_state = SLSTATE_IDLE;
+ break;
+ }
+
+
+
+ /* sll_bump(sl); send packet to the network layer */
+
+ /* sl->dev->stats.tx_packets++; send frames statistic */
+ /* netif_wake_queue(sl->dev); allow next Tx packet arrival */