Move MODULE_* to end of file

[elmcan.git] / module / elmcan.c

diff --git a/module/elmcan.c b/module/elmcan.c
index f358a46dafe86f3950be8a2ea15d8bfcb529746f..31aa8fcdf6887674892c5c6a3a03464d32b15350 100644 (file)
--- a/module/elmcan.c
+++ b/module/elmcan.c
@@ -4,9 +4,14 @@
  * This driver started as a derivative of linux/drivers/net/can/slcan.c
  * and my thanks go to the original authors for their inspiration, even
  * after almost none of their code is left.
+ *
+ * elmcan.c Author : Max Staudt <max-linux@enpas.org>
+ * slcan.c Author  : Oliver Hartkopp <socketcan@hartkopp.net>
+ * slip.c Authors  : Laurence Culhane <loz@holmes.demon.co.uk>
+ *                   Fred N. van Kempen <waltje@uwalt.nl.mugnet.org>
  */
 
-#define pr_fmt(fmt) "[elmcan] " fmt
+#define pr_fmt(fmt) "elmcan: " fmt
 
 #include <linux/init.h>
 #include <linux/module.h>
@@ -37,11 +42,6 @@
 #include <linux/can/led.h>
 #include <linux/can/rx-offload.h>
 
-MODULE_ALIAS_LDISC(N_DEVELOPMENT);
-MODULE_DESCRIPTION("ELM327 based CAN interface");
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Max Staudt <max-linux@enpas.org>");
-
 /* Line discipline ID number.
  * N_DEVELOPMENT will likely be defined from Linux 5.18 onwards:
  * https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git/commit/?h=tty-next&id=c2faf737abfb10f88f2d2612d573e9edc3c42c37
@@ -50,6 +50,11 @@ MODULE_AUTHOR("Max Staudt <max-linux@enpas.org>");
 #define N_DEVELOPMENT 29
 #endif
 
+/* Compatibility for Linux < 5.11 */
+#if LINUX_VERSION_CODE < KERNEL_VERSION(5,11,0)
+#define len can_dlc
+#endif
+
 #define ELM327_NAPI_WEIGHT 4
 
 #define ELM327_SIZE_RXBUF 256
@@ -314,20 +319,21 @@ static inline void elm327_hw_failure(struct elmcan *elm)
        struct can_frame *frame;
        struct sk_buff *skb;
 
+       elm->hw_failure = true;
+
+       elm->can.can_stats.bus_off++;
+       netif_stop_queue(elm->dev);
+       elm->can.state = CAN_STATE_BUS_OFF;
+       can_bus_off(elm->dev);
+
+       netdev_err(elm->dev, "ELM327 misbehaved. Blocking further communication.\n");
+
        skb = alloc_can_err_skb(elm->dev, &frame);
        if (!skb)
                return;
 
-       frame->data[5] = 'R';
-       frame->data[6] = 'I';
-       frame->data[7] = 'P';
-
+       frame->can_id |= CAN_ERR_BUSOFF;
        elm327_feed_frame_to_netdev(elm, skb);
-
-       netdev_err(elm->dev, "ELM327 misbehaved. Blocking further communication.\n");
-
-       elm->hw_failure = true;
-       can_bus_off(elm->dev);
 }
 
 /* Compare a buffer to a fixed string */
@@ -483,7 +489,7 @@ static int elm327_parse_frame(struct elmcan *elm, size_t len)
         */
 
        /* Read CAN data length */
-       frame->can_dlc = (hex_to_bin(elm->rxbuf[datastart - 2]) << 0);
+       frame->len = (hex_to_bin(elm->rxbuf[datastart - 2]) << 0);
 
        /* Read CAN ID */
        if (frame->can_id & CAN_EFF_FLAG) {
@@ -511,13 +517,13 @@ static int elm327_parse_frame(struct elmcan *elm, size_t len)
         * Note: RTR frames have a DLC, but no actual payload.
         */
        if (!(frame->can_id & CAN_RTR_FLAG) &&
-           (hexlen < frame->can_dlc * 3 + datastart)) {
+           (hexlen < frame->len * 3 + datastart)) {
                /* Incomplete frame.
                 * Probably the ELM327's RS232 TX buffer was full.
                 * Emit an error frame and exit.
                 */
                frame->can_id = CAN_ERR_FLAG | CAN_ERR_CRTL;
-               frame->can_dlc = CAN_ERR_DLC;
+               frame->len = CAN_ERR_DLC;
                frame->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
                elm327_feed_frame_to_netdev(elm, skb);
 
@@ -530,7 +536,7 @@ static int elm327_parse_frame(struct elmcan *elm, size_t len)
        }
 
        /* Parse the data nibbles. */
-       for (i = 0; i < frame->can_dlc; i++) {
+       for (i = 0; i < frame->len; i++) {
                frame->data[i] = (hex_to_bin(elm->rxbuf[datastart + 3*i]) << 4)
                               | (hex_to_bin(elm->rxbuf[datastart + 3*i + 1]));
        }
@@ -557,18 +563,13 @@ static void elm327_parse_line(struct elmcan *elm, size_t len)
        }
 
        /* Regular parsing */
-       switch (elm->state) {
-       case ELM_RECEIVING:
-               if (elm327_parse_frame(elm, len)) {
-                       /* Parse an error line. */
-                       elm327_parse_error(elm, len);
+       if (elm->state == ELM_RECEIVING
+           && elm327_parse_frame(elm, len)) {
+               /* Parse an error line. */
+               elm327_parse_error(elm, len);
 
-                       /* Start afresh. */
-                       elm327_kick_into_cmd_mode(elm);
-               }
-               break;
-       default:
-               break;
+               /* Start afresh. */
+               elm327_kick_into_cmd_mode(elm);
        }
 }
 
@@ -634,7 +635,7 @@ static void elm327_handle_prompt(struct elmcan *elm)
                        /* Send a regular CAN data frame */
                        int i;
 
-                       for (i = 0; i < frame->can_dlc; i++) {
+                       for (i = 0; i < frame->len; i++) {
                                sprintf(&local_txbuf[2 * i], "%02X",
                                        frame->data[i]);
                        }
@@ -668,6 +669,7 @@ static void elm327_drop_bytes(struct elmcan *elm, size_t i)
 static void elm327_parse_rxbuf(struct elmcan *elm)
 {
        size_t len;
+       int i;
 
        switch (elm->state) {
        case ELM_NOTINIT:
@@ -677,8 +679,6 @@ static void elm327_parse_rxbuf(struct elmcan *elm)
        case ELM_GETDUMMYCHAR:
        {
                /* Wait for 'y' or '>' */
-               int i;
-
                for (i = 0; i < elm->rxfill; i++) {
                        if (elm->rxbuf[i] == ELM327_DUMMY_CHAR) {
                                elm327_send(elm, "\r", 1);
@@ -843,11 +843,6 @@ static netdev_tx_t elmcan_netdev_start_xmit(struct sk_buff *skb,
        struct elmcan *elm = netdev_priv(dev);
        struct can_frame *frame = (struct can_frame *)skb->data;
 
-       if (!netif_running(dev))  {
-               netdev_warn(elm->dev, "xmit: iface is down.\n");
-               goto out;
-       }
-
        /* BHs are already disabled, so no spin_lock_bh().
         * See Documentation/networking/netdevices.txt
         */
@@ -871,7 +866,7 @@ static netdev_tx_t elmcan_netdev_start_xmit(struct sk_buff *skb,
        spin_unlock(&elm->lock);
 
        dev->stats.tx_packets++;
-       dev->stats.tx_bytes += frame->can_dlc;
+       dev->stats.tx_bytes += frame->len;
 
        can_led_event(dev, CAN_LED_EVENT_TX);
 
@@ -1287,3 +1282,8 @@ static void __exit elmcan_exit(void)
 
 module_init(elmcan_init);
 module_exit(elmcan_exit);
+
+MODULE_ALIAS_LDISC(N_DEVELOPMENT);
+MODULE_DESCRIPTION("ELM327 based CAN interface");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Max Staudt <max-linux@enpas.org>");