*
*/
+#define DEBUG 1 /* Enables pr_debug() printouts */
+
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/can.h>
#include <linux/kthread.h>
#include <linux/hrtimer.h>
+#include "linux/lin_bus.h"
/* Should be in include/linux/tty.h */
-#define N_SLLIN 25
+#define N_SLLIN 25
+/* -------------------------------- */
static __initdata const char banner[] =
KERN_INFO "sllin: serial line LIN interface driver\n";
MODULE_LICENSE("GPL");
MODULE_AUTHOR("");
-#define SLLIN_MAGIC 0x53CA
-// #define BREAK_BY_BAUD
+#define SLLIN_MAGIC 0x53CA
+/* #define BREAK_BY_BAUD */
static int maxdev = 10; /* MAX number of SLLIN channels;
This can be overridden with
MODULE_PARM_DESC(maxdev, "Maximum number of sllin interfaces");
/* maximum buffer len to store whole LIN message*/
-#define SLLIN_DATA_MAX 8
-#define SLLIN_BUFF_LEN (1 /*break*/ + 1 /*sync*/ + 1 /*ID*/ + \
- SLLIN_DATA_MAX + 1 /*checksum*/)
-#define SLLIN_BUFF_BREAK 0
-#define SLLIN_BUFF_SYNC 1
-#define SLLIN_BUFF_ID 2
-#define SLLIN_BUFF_DATA 3
-
-#define SLLIN_ID_MASK 0x3f
-#define SLLIN_ID_MAX SLLIN_ID_MASK
-#define SLLIN_CTRL_FRAME CAN_EFF_FLAG
+#define SLLIN_DATA_MAX 8
+#define SLLIN_BUFF_LEN (1 /*break*/ + 1 /*sync*/ + 1 /*ID*/ + \
+ SLLIN_DATA_MAX + 1 /*checksum*/)
+#define SLLIN_BUFF_BREAK 0
+#define SLLIN_BUFF_SYNC 1
+#define SLLIN_BUFF_ID 2
+#define SLLIN_BUFF_DATA 3
#define SLLIN_SAMPLES_PER_CHAR 10
#define SLLIN_CHARS_TO_TIMEOUT 12
struct sllin_conf_entry {
int dlc; /* Length of data in LIN frame */
-#define SLLIN_CANFR_FLAGS_OFFS 6 /* Lower 6 bits in can_id correspond to LIN ID */
-/* Save configuration for particular LIN ID */
-#define SLLIN_LIN_ID_CONF (1 << SLLIN_CANFR_FLAGS_OFFS)
-/* Publisher of particular LIN response is SLLIN Master */
-#define SLLIN_SRC_MASTER (1 << (SLLIN_CANFR_FLAGS_OFFS + 1))
-#define SLLIN_SRC_SLAVE (1 << (SLLIN_CANFR_FLAGS_OFFS + 2))
-#define SLLIN_SLAVE_LOCAL (1 << (SLLIN_CANFR_FLAGS_OFFS + 3))
-#define SLLIN_SLAVE_REMOTE (1 << (SLLIN_CANFR_FLAGS_OFFS + 4))
-#define SLLIN_LOC_SLAVE_CACHE (1 << (SLLIN_CANFR_FLAGS_OFFS + 5))
-#define SLLIN_CHECKSUM_EXTENDED (1 << (SLLIN_CANFR_FLAGS_OFFS + 6))
-
-#define SLLIN_ERR_RX_TIMEOUT (1 << (SLLIN_CANFR_FLAGS_OFFS + 7))
-#define SLLIN_ERR_CHECKSUM (1 << (SLLIN_CANFR_FLAGS_OFFS + 8))
-//#define SLLIN_ERR_FRAMING (1 << (SLLIN_CANFR_FLAGS_OFFS + 9))
-
canid_t frame_fl; /* LIN frame flags. Passed from userspace as canid_t data type */
u8 data[8]; /* LIN frame data payload */
};
dev_t line;
struct task_struct *kwthread;
- wait_queue_head_t kwt_wq;
+ wait_queue_head_t kwt_wq; /* Wait queue used by kwthread */
struct hrtimer rx_timer; /* RX timeout timer */
ktime_t rx_timer_timeout; /* RX timeout timer value */
struct sk_buff *tx_req_skb; /* Socket buffer with CAN frame received
from network stack*/
- struct sllin_conf_entry linfr_cache[SLLIN_ID_MAX + 1]; /* List with configurations for
- each of 0 to SLLIN_ID_MAX LIN IDs */
+ struct sllin_conf_entry linfr_cache[LIN_ID_MAX + 1]; /* List with configurations for
+ each of 0 to LIN_ID_MAX LIN IDs */
};
static struct net_device **sllin_devs;
static int sllin_configure_frame_cache(struct sllin *sl, struct can_frame *cf);
+/* Values of two parity bits in LIN Protected
+ Identifier for each particular LIN ID */
const unsigned char sllin_id_parity_table[] = {
- 0x80,0xc0,0x40,0x00,0xc0,0x80,0x00,0x40,
- 0x00,0x40,0xc0,0x80,0x40,0x00,0x80,0xc0,
- 0x40,0x00,0x80,0xc0,0x00,0x40,0xc0,0x80,
- 0xc0,0x80,0x00,0x40,0x80,0xc0,0x40,0x00,
- 0x00,0x40,0xc0,0x80,0x40,0x00,0x80,0xc0,
- 0x80,0xc0,0x40,0x00,0xc0,0x80,0x00,0x40,
- 0xc0,0x80,0x00,0x40,0x80,0xc0,0x40,0x00,
- 0x40,0x00,0x80,0xc0,0x00,0x40,0xc0,0x80
+ 0x80, 0xc0, 0x40, 0x00, 0xc0, 0x80, 0x00, 0x40,
+ 0x00, 0x40, 0xc0, 0x80, 0x40, 0x00, 0x80, 0xc0,
+ 0x40, 0x00, 0x80, 0xc0, 0x00, 0x40, 0xc0, 0x80,
+ 0xc0, 0x80, 0x00, 0x40, 0x80, 0xc0, 0x40, 0x00,
+ 0x00, 0x40, 0xc0, 0x80, 0x40, 0x00, 0x80, 0xc0,
+ 0x80, 0xc0, 0x40, 0x00, 0xc0, 0x80, 0x00, 0x40,
+ 0xc0, 0x80, 0x00, 0x40, 0x80, 0xc0, 0x40, 0x00,
+ 0x40, 0x00, 0x80, 0xc0, 0x00, 0x40, 0xc0, 0x80
};
+/**
+ * sltty_change_speed() -- Change baudrate of Serial device belonging to particular @tty
+ *
+ * @tty: Pointer to TTY to change speed for.
+ * @speed: Integer value of new speed. It is possible to
+ * assign non-standard values, i.e. those which
+ * are not defined in termbits.h.
+ */
static int sltty_change_speed(struct tty_struct *tty, unsigned speed)
{
struct ktermios old_termios;
}
+/**
+ * sll_bump() -- Send data of received LIN frame (existing in sl->rx_buff) as CAN frame
+ *
+ * @sl:
+ */
static void sll_bump(struct sllin *sl)
{
- sllin_send_canfr(sl, sl->rx_buff[SLLIN_BUFF_ID] & SLLIN_ID_MASK,
+ sllin_send_canfr(sl, sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK,
sl->rx_buff + SLLIN_BUFF_DATA,
sl->rx_cnt - SLLIN_BUFF_DATA - 1); /* without checksum */
}
sl->tx_cnt += actual;
if (sl->tx_cnt < sl->tx_lim) {
- printk(KERN_INFO "sllin_write_wakeup sent %d, remains %d, waiting\n",
+ pr_debug("sllin: sllin_write_wakeup sent %d, remains %d, waiting\n",
sl->tx_cnt, sl->tx_lim - sl->tx_cnt);
return;
}
set_bit(SLF_TXEVENT, &sl->flags);
wake_up(&sl->kwt_wq);
- printk(KERN_INFO "sllin_write_wakeup sent %d, wakeup\n", sl->tx_cnt);
+ pr_debug("sllin: sllin_write_wakeup sent %d, wakeup\n", sl->tx_cnt);
}
-/* Send a can_frame to a TTY queue. */
+/**
+ * sll_xmit() -- Send a can_frame to a TTY queue.
+ *
+ * @skb: Pointer to Socket buffer to be sent.
+ * @dev: Network device where @skb will be sent.
+ */
static netdev_tx_t sll_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct sllin *sl = netdev_priv(dev);
}
cf = (struct can_frame *) skb->data;
- if (cf->can_id & SLLIN_CTRL_FRAME) {
+ if (cf->can_id & LIN_CTRL_FRAME) {
sllin_configure_frame_cache(sl, cf);
goto free_out_unlock;
}
Routines looking at TTY side.
******************************************/
-/*
- * Handle the 'receiver data ready' interrupt.
- * This function is called by the 'tty_io' module in the kernel when
- * a block of SLLIN data has been received, which can now be decapsulated
- * and sent on to some IP layer for further processing. This will not
- * be re-entered while running but other ldisc functions may be called
- * in parallel
- */
-
static void sllin_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
struct sllin *sl = (struct sllin *) tty->disc_data;
- printk(KERN_INFO "sllin_receive_buf invoked\n");
+ pr_debug("sllin: sllin_receive_buf invoked\n");
if (!sl || sl->magic != SLLIN_MAGIC || !netif_running(sl->dev))
return;
if (fp && *fp++) {
if (!test_and_set_bit(SLF_ERROR, &sl->flags))
sl->dev->stats.rx_errors++;
- printk(KERN_INFO "sllin_receive_buf char 0x%02x ignored "
+ pr_debug("sllin: sllin_receive_buf char 0x%02x ignored "
"due marker 0x%02x, flags 0x%lx\n",
*cp, *(fp-1), sl->flags);
cp++;
sl->rx_buff[sl->rx_cnt++] = 0x00;
}
#endif
- printk(KERN_INFO "LIN_RX[%d]: 0x%02x\n", sl->rx_cnt, *cp);
+ pr_debug("sllin: 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);
+ pr_debug("sllin: sllin_receive_buf count %d, wakeup\n", sl->rx_cnt);
} else {
- printk(KERN_INFO "sllin_receive_buf count %d, waiting\n", sl->rx_cnt);
+ pr_debug("sllin: sllin_receive_buf count %d, waiting\n", sl->rx_cnt);
}
}
/*****************************************
* sllin message helper routines
*****************************************/
+/**
+ * sllin_report_error() -- Report an error by sending CAN frame \
+ * with particular error flag set in can_id
+ *
+ * @sl:
+ * @err: Error flag to be sent.
+ */
void sllin_report_error(struct sllin *sl, int err)
{
sllin_send_canfr(sl, 0 | CAN_EFF_FLAG |
- (err & ~SLLIN_ID_MASK), NULL, 0);
+ (err & ~LIN_ID_MASK), NULL, 0);
}
+/**
+ * sllin_configure_frame_cache() -- Configure particular entry in linfr_cache
+ *
+ * @sl:
+ * @cf: Pointer to CAN frame sent to this driver
+ * holding configuration information
+ */
static int sllin_configure_frame_cache(struct sllin *sl, struct can_frame *cf)
{
struct sllin_conf_entry *sce;
- if (!(cf->can_id & SLLIN_LIN_ID_CONF))
+ if (!(cf->can_id & LIN_ID_CONF))
return -1;
- sce = &sl->linfr_cache[cf->can_id & SLLIN_ID_MASK];
- printk(KERN_INFO "Setting frame cache with EFF CAN frame. "
- "LIN ID = %d\n", cf->can_id & SLLIN_ID_MASK);
+ sce = &sl->linfr_cache[cf->can_id & LIN_ID_MASK];
+ pr_debug("sllin: Setting frame cache with EFF CAN frame. "
+ "LIN ID = %d\n", cf->can_id & LIN_ID_MASK);
sce->dlc = cf->can_dlc;
if (sce->dlc > SLLIN_DATA_MAX)
sce->dlc = SLLIN_DATA_MAX;
- sce->frame_fl = (cf->can_id & ~SLLIN_ID_MASK) & CAN_EFF_MASK;
+ sce->frame_fl = (cf->can_id & ~LIN_ID_MASK) & CAN_EFF_MASK;
memcpy(sce->data, cf->data, cf->can_dlc);
return 0;
}
+/**
+ * sllin_checksum() -- Count checksum for particular data
+ *
+ * @data: Pointer to the buffer containing whole LIN
+ * frame (i.e. including break and sync bytes).
+ * @length: Length of the buffer.
+ * @enhanced_fl: Flag determining whether Enhanced or Classic
+ * checksum should be counted.
+ */
static inline unsigned sllin_checksum(unsigned char *data, int length, int enhanced_fl)
{
unsigned csum = 0;
int sllin_setup_msg(struct sllin *sl, int mode, int id,
unsigned char *data, int len)
{
- if (id > SLLIN_ID_MASK)
+ if (id > LIN_ID_MASK)
return -1;
if (!(mode & SLLIN_STPMSG_RESPONLY)) {
sl->tx_cnt += res;
}
- printk(KERN_INFO "sllin_send_tx_buff sent %d, remains %d\n",
+ pr_debug("sllin: sllin_send_tx_buff sent %d, remains %d\n",
sl->tx_cnt, remains);
return 0;
sl->tx_cnt = SLLIN_BUFF_SYNC;
- printk(KERN_INFO "sllin: Break sent.\n");
+ pr_debug("sllin: Break sent.\n");
set_bit(SLF_RXEVENT, &sl->flags);
wake_up(&sl->kwt_wq);
{
struct sllin *sl = container_of(hrtimer, struct sllin, rx_timer);
- sllin_report_error(sl, SLLIN_ERR_RX_TIMEOUT);
+ sllin_report_error(sl, LIN_ERR_RX_TIMEOUT);
set_bit(SLF_TMOUTEVENT, &sl->flags);
wake_up(&sl->kwt_wq);
return HRTIMER_NORESTART;
}
+/**
+ * sllin_rx_validate() -- Validate received frame, i,e. check checksum
+ *
+ * @sl:
+ */
static int sllin_rx_validate(struct sllin *sl)
{
int actual_id;
unsigned char rec_chcksm = sl->rx_buff[sl->rx_cnt - 1];
struct sllin_conf_entry *scf;
- actual_id = sl->rx_buff[SLLIN_BUFF_ID] & SLLIN_ID_MASK;
+ actual_id = sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK;
scf = &sl->linfr_cache[actual_id];
lin_dlc = scf->dlc;
- ext_chcks_fl = scf->frame_fl & SLLIN_CHECKSUM_EXTENDED;
+ ext_chcks_fl = scf->frame_fl & LIN_CHECKSUM_EXTENDED;
if (sllin_checksum(sl->rx_buff, sl->rx_cnt - 1, ext_chcks_fl) !=
rec_chcksm) {
int tx_bytes = 0; /* Used for Network statistics */
- printk(KERN_INFO "sllin: sllin_kwthread started.\n");
+ pr_debug("sllin: sllin_kwthread started.\n");
sched_setscheduler(current, SCHED_FIFO, &schparam);
clear_bit(SLF_ERROR, &sl->flags);
&& test_bit(SLF_MSGEVENT, &sl->flags)));
if (test_and_clear_bit(SLF_RXEVENT, &sl->flags)) {
- printk(KERN_INFO "sllin_kthread RXEVENT \n");
+ pr_debug("sllin: sllin_kthread RXEVENT \n");
}
if (test_and_clear_bit(SLF_TXEVENT, &sl->flags)) {
- printk(KERN_INFO "sllin_kthread TXEVENT \n");
+ pr_debug("sllin: sllin_kthread TXEVENT \n");
}
if (test_and_clear_bit(SLF_TMOUTEVENT, &sl->flags)) {
- printk(KERN_INFO "sllin_kthread TMOUTEVENT \n");
+ 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;
/* SFF RTR CAN frame -> LIN header */
if (cf->can_id & CAN_RTR_FLAG) {
spin_lock(&sl->lock);
- printk(KERN_INFO "%s: RTR SFF CAN frame, ID = %x\n",
- __FUNCTION__, cf->can_id & SLLIN_ID_MASK);
+ pr_debug("sllin: %s: RTR SFF CAN frame, ID = %x\n",
+ __FUNCTION__, cf->can_id & LIN_ID_MASK);
/* Is there Slave response in linfr_cache to be sent? */
- if ((sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].frame_fl &
- SLLIN_LOC_SLAVE_CACHE)
- && (sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].dlc > 0)) {
+ if ((sl->linfr_cache[cf->can_id & LIN_ID_MASK].frame_fl &
+ LIN_LOC_SLAVE_CACHE)
+ && (sl->linfr_cache[cf->can_id & LIN_ID_MASK].dlc > 0)) {
- printk(KERN_INFO "Sending LIN response from linfr_cache\n");
- lin_data = sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].data;
- lin_dlc = sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].dlc;
+ pr_debug("sllin: Sending LIN response from linfr_cache\n");
+ lin_data = sl->linfr_cache[cf->can_id & LIN_ID_MASK].data;
+ lin_dlc = sl->linfr_cache[cf->can_id & LIN_ID_MASK].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;
} else {
lin_data = NULL;
- lin_dlc = sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].dlc;
+ lin_dlc = sl->linfr_cache[cf->can_id & LIN_ID_MASK].dlc;
}
spin_unlock(&sl->lock);
} else { /* SFF NON-RTR CAN frame -> LIN header + LIN response */
- printk(KERN_INFO "%s: NON-RTR SFF CAN frame, ID = %x\n",
- __FUNCTION__, (int)cf->can_id & SLLIN_ID_MASK);
+ pr_debug("sllin: %s: NON-RTR SFF CAN frame, ID = %x\n",
+ __FUNCTION__, (int)cf->can_id & LIN_ID_MASK);
lin_data = cf->data;
lin_dlc = cf->can_dlc;
tx_bytes = lin_dlc;
}
- if (sllin_setup_msg(sl, 0, cf->can_id & SLLIN_ID_MASK,
+ if (sllin_setup_msg(sl, 0, cf->can_id & LIN_ID_MASK,
lin_data, lin_dlc) != -1) {
sl->id_to_send = true;
cf = (struct can_frame *)sl->tx_req_skb->data;
lin_buff = (sl->lin_master) ? sl->tx_buff : sl->rx_buff;
- if (cf->can_id == (lin_buff[SLLIN_BUFF_ID] & SLLIN_ID_MASK)) {
+ if (cf->can_id == (lin_buff[SLLIN_BUFF_ID] & LIN_ID_MASK)) {
if (sllin_setup_msg(sl, SLLIN_STPMSG_RESPONLY,
- cf->can_id & SLLIN_ID_MASK,
+ cf->can_id & LIN_ID_MASK,
cf->data, cf->can_dlc) != -1) {
sl->rx_expect = sl->tx_lim;
continue;
hrtimer_cancel(&sl->rx_timer);
- printk(KERN_INFO "sllin: response received ID %d len %d\n",
+ pr_debug("sllin: response received ID %d len %d\n",
sl->rx_buff[SLLIN_BUFF_ID], sl->rx_cnt - SLLIN_BUFF_DATA - 1);
if (sllin_rx_validate(sl) == -1) {
- printk("sllin: RX validation failed.\n");
- sllin_report_error(sl, SLLIN_ERR_CHECKSUM);
+ pr_debug("sllin: RX validation failed.\n");
+ sllin_report_error(sl, LIN_ERR_CHECKSUM);
//FIXME tx_stat.err++
} else {
// send CAN non-RTR frame with data
- printk(KERN_INFO "sllin: sending NON-RTR CAN"
+ pr_debug("sllin: sending NON-RTR CAN"
"frame with LIN payload.");
sll_bump(sl); //send packet to the network layer
}
continue;
sll_bump(sl); //send packet to the network layer
- printk(KERN_INFO "sllin: response sent ID %d len %d\n",
+ pr_debug("sllin: response sent ID %d len %d\n",
sl->rx_buff[SLLIN_BUFF_ID], sl->rx_cnt - SLLIN_BUFF_DATA - 1);
sl->id_to_send = false;
}
hrtimer_cancel(&sl->rx_timer);
- printk(KERN_INFO "sllin: sllin_kwthread stopped.\n");
+ pr_debug("sllin: sllin_kwthread stopped.\n");
return 0;
}
maxdev = 4; /* Sanity */
printk(banner);
- printk(KERN_INFO "sllin: %d dynamic interface channels.\n", maxdev);
+ pr_debug("sllin: %d dynamic interface channels.\n", maxdev);
sllin_devs = kzalloc(sizeof(struct net_device *)*maxdev, GFP_KERNEL);
if (!sllin_devs) {
}
#ifdef BREAK_BY_BAUD
- printk(KERN_INFO "sllin: Break is generated by baud-rate change.");
+ pr_debug("sllin: Break is generated by baud-rate change.");
#else
- printk(KERN_INFO "sllin: Break is generated manually with tiny sleep.");
+ pr_debug("sllin: Break is generated manually with tiny sleep.");
#endif
return status;