/*
- * slcan.c - serial line CAN interface driver (using tty line discipline)
+ * sllin.c - serial line LIN interface driver (using tty line discipline)
*
- * This file is derived from linux/drivers/net/slip.c
- *
- * slip.c Authors : Laurence Culhane <loz@holmes.demon.co.uk>
- * Fred N. van Kempen <waltje@uwalt.nl.mugnet.org>
- * slcan.c Author : Oliver Hartkopp <socketcan@hartkopp.net>
+ * This file is derived from drivers/net/can/slcan.c
+ * slcan.c Author: Oliver Hartkopp <socketcan@hartkopp.net>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* 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 */
+
#include <linux/module.h>
#include <linux/moduleparam.h>
-#include <asm/system.h>
#include <linux/uaccess.h>
#include <linux/bitops.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/init.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
+/* -------------------------------- */
static __initdata const char banner[] =
- KERN_INFO "slcan: serial line CAN interface driver\n";
+ KERN_INFO "sllin: serial line LIN interface driver\n";
-MODULE_ALIAS_LDISC(N_SLCAN);
-MODULE_DESCRIPTION("serial line CAN interface");
+MODULE_ALIAS_LDISC(N_SLLIN);
+MODULE_DESCRIPTION("serial line LIN interface");
MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Oliver Hartkopp <socketcan@hartkopp.net>");
+MODULE_AUTHOR("Pavel Pisa <pisa@cmp.felk.cvut.cz>");
+
+#define SLLIN_MAGIC 0x53CA
+/* #define BREAK_BY_BAUD */
-#define SLCAN_MAGIC 0x53CA
+static bool master = true;
+static int baudrate; /* Use LIN_DEFAULT_BAUDRATE when not set */
-static int maxdev = 10; /* MAX number of SLCAN channels;
+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 slcan.ko maxdev=nnn */
+ insmod sllin.ko maxdev=nnn */
module_param(maxdev, int, 0);
-MODULE_PARM_DESC(maxdev, "Maximum number of slcan interfaces");
+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_SAMPLES_PER_CHAR 10
+#define SLLIN_CHARS_TO_TIMEOUT 24
+
+enum slstate {
+ SLSTATE_IDLE = 0,
+ SLSTATE_BREAK_SENT,
+ SLSTATE_ID_SENT,
+ SLSTATE_RESPONSE_WAIT, /* Wait for response */
+ SLSTATE_RESPONSE_WAIT_BUS, /* Wait for response from LIN bus
+ only (CAN frames from network stack
+ are not processed in this moment) */
+ SLSTATE_RESPONSE_SENT,
+};
-/* maximum rx buffer len: extended CAN frame with timestamp */
-#define SLC_MTU (sizeof("T1111222281122334455667788EA5F\r")+1)
+struct sllin_conf_entry {
+ int dlc; /* Length of data in LIN frame */
+ canid_t frame_fl; /* LIN frame flags. Passed from userspace as
+ canid_t data type */
+ u8 data[8]; /* LIN frame data payload */
+};
-struct slcan {
+struct sllin {
int magic;
/* Various fields. */
struct net_device *dev; /* easy for intr handling */
spinlock_t lock;
- /* These are pointers to the malloc()ed frame buffers. */
- unsigned char rbuff[SLC_MTU]; /* receiver buffer */
- int rcount; /* received chars counter */
- unsigned char xbuff[SLC_MTU]; /* transmitter buffer */
- unsigned char *xhead; /* pointer to next XMIT byte */
- int xleft; /* bytes left in XMIT queue */
+ /* LIN message buffer and actual processed data counts */
+ unsigned char rx_buff[SLLIN_BUFF_LEN]; /* LIN Rx buffer */
+ unsigned char tx_buff[SLLIN_BUFF_LEN]; /* LIN Tx buffer */
+ int rx_expect; /* expected number of Rx chars */
+ int rx_lim; /* maximum Rx chars for current frame */
+ int rx_cnt; /* message buffer Rx fill level */
+ int tx_lim; /* actual limit of bytes to Tx */
+ int tx_cnt; /* number of already Tx bytes */
+ char lin_master; /* node is a master node */
+ int lin_baud; /* LIN baudrate */
+ int lin_state; /* state */
+ char id_to_send; /* there is ID to be sent */
+ char data_to_send; /* there are data to be sent */
+ char resp_len_known; /* Length of the response is known */
+ char header_received;/* In Slave mode, set when header was already
+ received */
+ char rx_len_unknown; /* We are not sure how much data will be sent to us --
+ we just guess the length */
unsigned long flags; /* Flag values/ mode etc */
#define SLF_INUSE 0 /* Channel in use */
#define SLF_ERROR 1 /* Parity, etc. error */
+#define SLF_RXEVENT 2 /* Rx wake event */
+#define SLF_TXEVENT 3 /* Tx wake event */
+#define SLF_MSGEVENT 4 /* CAN message to sent */
+#define SLF_TMOUTEVENT 5 /* Timeout on received data */
+#define SLF_TXBUFF_RQ 6 /* Req. to send buffer to UART*/
+#define SLF_TXBUFF_INPR 7 /* Above request in progress */
- unsigned char leased;
dev_t line;
- pid_t pid;
+ struct task_struct *kwthread;
+ 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*/
+
+ /* List with configurations for each of 0 to LIN_ID_MAX LIN IDs */
+ struct sllin_conf_entry linfr_cache[LIN_ID_MAX + 1];
+ spinlock_t linfr_lock; /* frame cache and buffers lock */
};
-static struct net_device **slcan_devs;
-
- /************************************************************************
- * SLCAN ENCAPSULATION FORMAT *
- ************************************************************************/
+static struct net_device **sllin_devs;
+static int sllin_configure_frame_cache(struct sllin *sl, struct can_frame *cf);
+static void sllin_slave_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count);
+static void sllin_master_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count);
+
+
+/* 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
+};
-/*
- * A CAN frame has a can_id (11 bit standard frame format OR 29 bit extended
- * frame format) a data length code (can_dlc) which can be from 0 to 8
- * and up to <can_dlc> data bytes as payload.
- * Additionally a CAN frame may become a remote transmission frame if the
- * RTR-bit is set. This causes another ECU to send a CAN frame with the
- * given can_id.
- *
- * The SLCAN ASCII representation of these different frame types is:
- * <type> <id> <dlc> <data>*
- *
- * Extended frames (29 bit) are defined by capital characters in the type.
- * RTR frames are defined as 'r' types - normal frames have 't' type:
- * t => 11 bit data frame
- * r => 11 bit RTR frame
- * T => 29 bit data frame
- * R => 29 bit RTR frame
- *
- * The <id> is 3 (standard) or 8 (extended) bytes in ASCII Hex (base64).
- * The <dlc> is a one byte ASCII number ('0' - '8')
- * The <data> section has at much ASCII Hex bytes as defined by the <dlc>
- *
- * Examples:
- *
- * t1230 : can_id 0x123, can_dlc 0, no data
- * t4563112233 : can_id 0x456, can_dlc 3, data 0x11 0x22 0x33
- * T12ABCDEF2AA55 : extended can_id 0x12ABCDEF, can_dlc 2, data 0xAA 0x55
- * r1230 : can_id 0x123, can_dlc 0, no data, remote transmission request
+/**
+ * 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;
+ int cflag;
- /************************************************************************
- * STANDARD SLCAN DECAPSULATION *
- ************************************************************************/
+ mutex_lock(&tty->termios_mutex);
-static int asc2nibble(char c)
-{
+ old_termios = *(tty->termios);
- if ((c >= '0') && (c <= '9'))
- return c - '0';
+ 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;
- if ((c >= 'A') && (c <= 'F'))
- return c - 'A' + 10;
+ /* Enable interrupt when UART-Break or Framing error received */
+ tty->termios->c_iflag = BRKINT | INPCK;
- if ((c >= 'a') && (c <= 'f'))
- return c - 'a' + 10;
+ tty_encode_baud_rate(tty, speed, speed);
- return 16; /* error */
+ if (tty->ops->set_termios)
+ tty->ops->set_termios(tty, &old_termios);
+
+ mutex_unlock(&tty->termios_mutex);
+
+ return 0;
}
-/* Send one completely decapsulated can_frame to the network layer */
-static void slc_bump(struct slcan *sl)
+/* Send one can_frame to the network layer */
+static void sllin_send_canfr(struct sllin *sl, canid_t id, char *data, int len)
{
struct sk_buff *skb;
struct can_frame cf;
- int i, dlc_pos, tmp;
- unsigned long ultmp;
- char cmd = sl->rbuff[0];
-
- if ((cmd != 't') && (cmd != 'T') && (cmd != 'r') && (cmd != 'R'))
- return;
-
- if (cmd & 0x20) /* tiny chars 'r' 't' => standard frame format */
- dlc_pos = 4; /* dlc position tiiid */
- else
- dlc_pos = 9; /* dlc position Tiiiiiiiid */
-
- if (!((sl->rbuff[dlc_pos] >= '0') && (sl->rbuff[dlc_pos] < '9')))
- return;
-
- cf.can_dlc = sl->rbuff[dlc_pos] - '0'; /* get can_dlc from ASCII val */
-
- sl->rbuff[dlc_pos] = 0; /* terminate can_id string */
-
- if (strict_strtoul(sl->rbuff+1, 16, &ultmp))
- return;
-
- cf.can_id = ultmp;
-
- if (!(cmd & 0x20)) /* NO tiny chars => extended frame format */
- cf.can_id |= CAN_EFF_FLAG;
-
- if ((cmd | 0x20) == 'r') /* RTR frame */
- cf.can_id |= CAN_RTR_FLAG;
-
- *(u64 *) (&cf.data) = 0; /* clear payload */
-
- for (i = 0, dlc_pos++; i < cf.can_dlc; i++) {
-
- tmp = asc2nibble(sl->rbuff[dlc_pos++]);
- if (tmp > 0x0F)
- return;
- cf.data[i] = (tmp << 4);
- tmp = asc2nibble(sl->rbuff[dlc_pos++]);
- if (tmp > 0x0F)
- return;
- cf.data[i] |= tmp;
- }
+ cf.can_id = id;
+ cf.can_dlc = len;
+ if (cf.can_dlc > 0)
+ memcpy(&cf.data, data, cf.can_dlc);
skb = dev_alloc_skb(sizeof(struct can_frame));
if (!skb)
sl->dev->stats.rx_bytes += cf.can_dlc;
}
-/* parse tty input stream */
-static void slcan_unesc(struct slcan *sl, unsigned char s)
+/**
+ * sll_bump() -- Send data of received LIN frame (existing in sl->rx_buff)
+ * as CAN frame
+ *
+ * @sl:
+ */
+static void sll_bump(struct sllin *sl)
{
+ int len = sl->rx_cnt - SLLIN_BUFF_DATA - 1; /* without checksum */
+ len = (len < 0) ? 0 : len;
- if ((s == '\r') || (s == '\a')) { /* CR or BEL ends the pdu */
- if (!test_and_clear_bit(SLF_ERROR, &sl->flags) &&
- (sl->rcount > 4)) {
- slc_bump(sl);
- }
- sl->rcount = 0;
- } else {
- if (!test_bit(SLF_ERROR, &sl->flags)) {
- if (sl->rcount < SLC_MTU) {
- sl->rbuff[sl->rcount++] = s;
- return;
- } else {
- sl->dev->stats.rx_over_errors++;
- set_bit(SLF_ERROR, &sl->flags);
- }
- }
- }
+ sllin_send_canfr(sl, sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK,
+ sl->rx_buff + SLLIN_BUFF_DATA, len);
}
- /************************************************************************
- * STANDARD SLCAN ENCAPSULATION *
- ************************************************************************/
-
-/* Encapsulate one can_frame and stuff into a TTY queue. */
-static void slc_encaps(struct slcan *sl, struct can_frame *cf)
+static void sll_send_rtr(struct sllin *sl)
{
- int actual, idx, i;
- char cmd;
-
- if (cf->can_id & CAN_RTR_FLAG)
- cmd = 'R'; /* becomes 'r' in standard frame format */
- else
- cmd = 'T'; /* becomes 't' in standard frame format */
-
- if (cf->can_id & CAN_EFF_FLAG)
- sprintf(sl->xbuff, "%c%08X%d", cmd,
- cf->can_id & CAN_EFF_MASK, cf->can_dlc);
- else
- sprintf(sl->xbuff, "%c%03X%d", cmd | 0x20,
- cf->can_id & CAN_SFF_MASK, cf->can_dlc);
-
- idx = strlen(sl->xbuff);
-
- for (i = 0; i < cf->can_dlc; i++)
- sprintf(&sl->xbuff[idx + 2*i], "%02X", cf->data[i]);
-
- strcat(sl->xbuff, "\r"); /* add terminating character */
-
- /* Order of next two lines is *very* important.
- * When we are sending a little amount of data,
- * the transfer may be completed inside the ops->write()
- * routine, because it's running with interrupts enabled.
- * In this case we *never* got WRITE_WAKEUP event,
- * if we did not request it before write operation.
- * 14 Oct 1994 Dmitry Gorodchanin.
- */
- set_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
- actual = sl->tty->ops->write(sl->tty, sl->xbuff, strlen(sl->xbuff));
- sl->xleft = strlen(sl->xbuff) - actual;
- sl->xhead = sl->xbuff + actual;
- sl->dev->stats.tx_bytes += cf->can_dlc;
+ sllin_send_canfr(sl, (sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK) |
+ CAN_RTR_FLAG, NULL, 0);
}
/*
* Called by the driver when there's room for more data. If we have
* more packets to send, we send them here.
*/
-static void slcan_write_wakeup(struct tty_struct *tty)
+static void sllin_write_wakeup(struct tty_struct *tty)
{
- int actual;
- struct slcan *sl = (struct slcan *) tty->disc_data;
+ int actual = 0;
+ int remains;
+ struct sllin *sl = (struct sllin *) tty->disc_data;
/* First make sure we're connected. */
- if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev))
+ if (!sl || sl->magic != SLLIN_MAGIC || !netif_running(sl->dev))
return;
- if (sl->xleft <= 0) {
- /* Now serial buffer is almost free & we can start
- * transmission of another packet */
- sl->dev->stats.tx_packets++;
- clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
- netif_wake_queue(sl->dev);
+ set_bit(SLF_TXBUFF_RQ, &sl->flags);
+ do {
+ if (unlikely(test_and_set_bit(SLF_TXBUFF_INPR, &sl->flags)))
+ return; /* ongoing concurrent processing */
+
+ clear_bit(SLF_TXBUFF_RQ, &sl->flags);
+ smp_mb__after_clear_bit();
+
+ if (sl->lin_state != SLSTATE_BREAK_SENT)
+ remains = sl->tx_lim - sl->tx_cnt;
+ else
+ remains = SLLIN_BUFF_BREAK + 1 - sl->tx_cnt;
+
+ if (remains > 0) {
+ actual = tty->ops->write(tty, sl->tx_buff + sl->tx_cnt,
+ sl->tx_cnt - sl->tx_lim);
+ sl->tx_cnt += actual;
+ remains -= actual;
+ }
+ clear_bit(SLF_TXBUFF_INPR, &sl->flags);
+ smp_mb__after_clear_bit();
+
+ } while (unlikely(test_bit(SLF_TXBUFF_RQ, &sl->flags)));
+
+ if ((remains > 0) && (actual >= 0)) {
+ pr_debug("sllin: sllin_write_wakeup sent %d, remains %d, waiting\n",
+ sl->tx_cnt, sl->tx_lim - sl->tx_cnt);
return;
}
- actual = tty->ops->write(tty, sl->xhead, sl->xleft);
- sl->xleft -= actual;
- sl->xhead += actual;
+ clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+ set_bit(SLF_TXEVENT, &sl->flags);
+ wake_up(&sl->kwt_wq);
+
+ pr_debug("sllin: sllin_write_wakeup sent %d, wakeup\n", sl->tx_cnt);
}
-/* Send a can_frame to a TTY queue. */
-static netdev_tx_t slc_xmit(struct sk_buff *skb, struct net_device *dev)
+/**
+ * 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 slcan *sl = netdev_priv(dev);
+ struct sllin *sl = netdev_priv(dev);
+ struct can_frame *cf;
if (skb->len != sizeof(struct can_frame))
- goto out;
+ goto err_out;
spin_lock(&sl->lock);
if (!netif_running(dev)) {
- spin_unlock(&sl->lock);
- printk(KERN_WARNING "%s: xmit: iface is down\n", dev->name);
- goto out;
+ pr_warn("%s: xmit: iface is down\n", dev->name);
+ goto err_out_unlock;
}
if (sl->tty == NULL) {
- spin_unlock(&sl->lock);
- goto out;
+ pr_warn("%s: xmit: no tty device connected\n", dev->name);
+ goto err_out_unlock;
+ }
+
+ cf = (struct can_frame *) skb->data;
+ if (cf->can_id & LIN_CTRL_FRAME) {
+ sllin_configure_frame_cache(sl, cf);
+ goto free_out_unlock;
}
netif_stop_queue(sl->dev);
- slc_encaps(sl, (struct can_frame *) skb->data); /* encaps & send */
+
+ sl->tx_req_skb = skb;
+ set_bit(SLF_MSGEVENT, &sl->flags);
+ wake_up(&sl->kwt_wq);
spin_unlock(&sl->lock);
+ return NETDEV_TX_OK;
-out:
+free_out_unlock:
+err_out_unlock:
+ spin_unlock(&sl->lock);
+err_out:
kfree_skb(skb);
return NETDEV_TX_OK;
}
******************************************/
/* Netdevice UP -> DOWN routine */
-static int slc_close(struct net_device *dev)
+static int sll_close(struct net_device *dev)
{
- struct slcan *sl = netdev_priv(dev);
+ struct sllin *sl = netdev_priv(dev);
spin_lock_bh(&sl->lock);
if (sl->tty) {
clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags);
}
netif_stop_queue(dev);
- sl->rcount = 0;
- sl->xleft = 0;
+ sl->rx_expect = 0;
+ sl->tx_lim = 0;
spin_unlock_bh(&sl->lock);
return 0;
}
/* Netdevice DOWN -> UP routine */
-static int slc_open(struct net_device *dev)
+static int sll_open(struct net_device *dev)
{
- struct slcan *sl = netdev_priv(dev);
+ struct sllin *sl = netdev_priv(dev);
+
+ pr_debug("sllin: %s() invoked\n", __func__);
if (sl->tty == NULL)
return -ENODEV;
return 0;
}
-/* Hook the destructor so we can free slcan devs at the right point in time */
-static void slc_free_netdev(struct net_device *dev)
+/* Hook the destructor so we can free sllin devs at the right point in time */
+static void sll_free_netdev(struct net_device *dev)
{
int i = dev->base_addr;
free_netdev(dev);
- slcan_devs[i] = NULL;
+ sllin_devs[i] = NULL;
}
-static const struct net_device_ops slc_netdev_ops = {
- .ndo_open = slc_open,
- .ndo_stop = slc_close,
- .ndo_start_xmit = slc_xmit,
+static const struct net_device_ops sll_netdev_ops = {
+ .ndo_open = sll_open,
+ .ndo_stop = sll_close,
+ .ndo_start_xmit = sll_xmit,
};
-static void slc_setup(struct net_device *dev)
+static void sll_setup(struct net_device *dev)
{
- dev->netdev_ops = &slc_netdev_ops;
- dev->destructor = slc_free_netdev;
+ dev->netdev_ops = &sll_netdev_ops;
+ dev->destructor = sll_free_netdev;
dev->hard_header_len = 0;
dev->addr_len = 0;
/* New-style flags. */
dev->flags = IFF_NOARP;
- dev->features = NETIF_F_NO_CSUM;
+ dev->features = NETIF_F_HW_CSUM; /* NETIF_F_NO_CSUM;*/
}
/******************************************
Routines looking at TTY side.
******************************************/
+static void sllin_master_receive_buf(struct tty_struct *tty,
+ const unsigned char *cp, char *fp, int count)
+{
+ struct sllin *sl = (struct sllin *) tty->disc_data;
-/*
- * Handle the 'receiver data ready' interrupt.
- * This function is called by the 'tty_io' module in the kernel when
- * a block of SLCAN 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
- */
+ /* Read the characters out of the buffer */
+ while (count--) {
+ if (fp && *fp++) {
+ pr_debug("sllin: sllin_receive_buf char 0x%02x ignored "
+ "due marker 0x%02x, flags 0x%lx\n",
+ *cp, *(fp-1), sl->flags);
+
+ /* i.e. Real error -- not Break */
+ if (sl->rx_cnt > SLLIN_BUFF_BREAK) {
+ set_bit(SLF_ERROR, &sl->flags);
+ wake_up(&sl->kwt_wq);
+ return;
+ }
+ }
+
+#ifndef BREAK_BY_BAUD
+ /* We didn't receive Break character -- fake it! */
+ if ((sl->rx_cnt == SLLIN_BUFF_BREAK) && (*cp == 0x55)) {
+ pr_debug("sllin: LIN_RX[%d]: 0x00\n", sl->rx_cnt);
+ sl->rx_buff[sl->rx_cnt++] = 0x00;
+ }
+#endif /* BREAK_BY_BAUD */
+
+ if (sl->rx_cnt < SLLIN_BUFF_LEN) {
+ 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);
+ pr_debug("sllin: sllin_receive_buf count %d, wakeup\n", sl->rx_cnt);
+ } else {
+ pr_debug("sllin: sllin_receive_buf count %d, waiting\n", sl->rx_cnt);
+ }
+}
-static void slcan_receive_buf(struct tty_struct *tty,
+
+static void sllin_slave_receive_buf(struct tty_struct *tty,
const unsigned char *cp, char *fp, int count)
{
- struct slcan *sl = (struct slcan *) tty->disc_data;
+ struct sllin *sl = (struct sllin *) tty->disc_data;
+ int lin_id;
+ struct sllin_conf_entry *sce;
- if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev))
- return;
/* 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++;
- cp++;
+ pr_debug("sllin: sllin_receive_buf char 0x%02x ignored "
+ "due marker 0x%02x, flags 0x%lx\n",
+ *cp, *(fp-1), sl->flags);
+
+ /* Received Break */
+ sl->rx_cnt = 0;
+ sl->rx_expect = SLLIN_BUFF_ID + 1;
+ sl->rx_len_unknown = false; /* We do know exact length of the header */
+ sl->header_received = false;
+ }
+
+ if (sl->rx_cnt < SLLIN_BUFF_LEN) {
+ pr_debug("sllin: LIN_RX[%d]: 0x%02x\n", sl->rx_cnt, *cp);
+
+ /* We did not receive break (0x00) character */
+ if ((sl->rx_cnt == SLLIN_BUFF_BREAK) && (*cp == 0x55)) {
+ sl->rx_buff[sl->rx_cnt++] = 0x00;
+ }
+
+ if (sl->rx_cnt == SLLIN_BUFF_SYNC) {
+ /* 'Duplicated' break character -- ignore */
+ if (*cp == 0x00) {
+ cp++;
+ continue;
+ }
+
+ /* Wrong sync character */
+ if (*cp != 0x55)
+ break;
+ }
+
+ sl->rx_buff[sl->rx_cnt++] = *cp++;
+ }
+
+ /* Header received */
+ if ((sl->header_received == false) && (sl->rx_cnt >= (SLLIN_BUFF_ID + 1))) {
+ unsigned long flags;
+
+ lin_id = sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK;
+ sce = &sl->linfr_cache[lin_id];
+
+ spin_lock_irqsave(&sl->linfr_lock, flags);
+ /* Is the length of data set in frame cache? */
+ if (sce->frame_fl & LIN_CACHE_RESPONSE) {
+ sl->rx_expect += sce->dlc;
+ sl->rx_len_unknown = false;
+ } else {
+ sl->rx_expect += SLLIN_DATA_MAX + 1; /* + checksum */
+ sl->rx_len_unknown = true;
+ }
+ spin_unlock_irqrestore(&sl->linfr_lock, flags);
+
+ sl->header_received = true;
+ sll_send_rtr(sl);
continue;
}
- slcan_unesc(sl, *cp++);
+
+ /* Response received */
+ if ((sl->header_received == true) &&
+ ((sl->rx_cnt >= sl->rx_expect) ||
+ ((sl->rx_len_unknown == true) && (count == 0)))) {
+
+ sll_bump(sl);
+ pr_debug("sllin: Received LIN header & LIN response. "
+ "rx_cnt = %u, rx_expect = %u\n", sl->rx_cnt,
+ sl->rx_expect);
+
+ /* Prepare for reception of new header */
+ sl->rx_cnt = 0;
+ sl->rx_expect = SLLIN_BUFF_ID + 1;
+ sl->rx_len_unknown = false; /* We do know exact length of the header */
+ sl->header_received = false;
+ }
+ }
+}
+
+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;
+ pr_debug("sllin: sllin_receive_buf invoked, count = %u\n", count);
+
+ if (!sl || sl->magic != SLLIN_MAGIC || !netif_running(sl->dev))
+ return;
+
+ if (sl->lin_master)
+ sllin_master_receive_buf(tty, cp, fp, count);
+ else
+ sllin_slave_receive_buf(tty, cp, fp, count);
+
+}
+
+/*****************************************
+ * 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)
+{
+ switch (err) {
+ case LIN_ERR_CHECKSUM:
+ sl->dev->stats.rx_crc_errors++;
+ break;
+
+ 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 |
+ (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)
+{
+ unsigned long flags;
+ struct sllin_conf_entry *sce;
+
+ if (!(cf->can_id & LIN_CTRL_FRAME))
+ return -1;
+
+ 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);
+
+ spin_lock_irqsave(&sl->linfr_lock, flags);
+
+ sce->dlc = cf->can_dlc;
+ if (sce->dlc > SLLIN_DATA_MAX)
+ sce->dlc = SLLIN_DATA_MAX;
+
+ sce->frame_fl = (cf->can_id & ~LIN_ID_MASK) & CAN_EFF_MASK;
+ memcpy(sce->data, cf->data, cf->can_dlc);
+
+ spin_unlock_irqrestore(&sl->linfr_lock, flags);
+
+ 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 i;
+
+ if (enhanced_fl)
+ i = SLLIN_BUFF_ID;
+ else
+ i = SLLIN_BUFF_DATA;
+
+ for (; i < length; i++) {
+ csum += data[i];
+ if (csum > 255)
+ csum -= 255;
+ }
+
+ return ~csum & 0xff;
+}
+
+#define SLLIN_STPMSG_RESPONLY (1) /* Message will be LIN Response only */
+#define SLLIN_STPMSG_CHCKSUM_CLS (1 << 1)
+#define SLLIN_STPMSG_CHCKSUM_ENH (1 << 2)
+
+int sllin_setup_msg(struct sllin *sl, int mode, int id,
+ unsigned char *data, int len)
+{
+ if (id > LIN_ID_MASK)
+ return -1;
+
+ if (!(mode & SLLIN_STPMSG_RESPONLY)) {
+ sl->rx_cnt = 0;
+ sl->tx_cnt = 0;
+ sl->rx_expect = 0;
+ sl->rx_lim = SLLIN_BUFF_LEN;
+ }
+
+ 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) {
+ sl->tx_lim += len;
+ memcpy(sl->tx_buff + SLLIN_BUFF_DATA, data, len);
+ sl->tx_buff[sl->tx_lim] = sllin_checksum(sl->tx_buff,
+ sl->tx_lim, mode & SLLIN_STPMSG_CHCKSUM_ENH);
+ sl->tx_lim++;
+ }
+ if (len != 0)
+ sl->rx_lim = SLLIN_BUFF_DATA + len + 1;
+
+ 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)
+{
+ struct tty_struct *tty = sl->tty;
+ int remains;
+ int res;
+
+ set_bit(SLF_TXBUFF_RQ, &sl->flags);
+ do {
+ if (unlikely(test_and_set_bit(SLF_TXBUFF_INPR, &sl->flags)))
+ return 0; /* ongoing concurrent processing */
+
+ clear_bit(SLF_TXBUFF_RQ, &sl->flags);
+ smp_mb__after_clear_bit();
+
+#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)
+ goto error_in_write;
+
+ 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);
+ goto error_in_write;
+ }
+
+ remains -= res;
+ sl->tx_cnt += res;
+ }
+
+ pr_debug("sllin: sllin_send_tx_buff sent %d, remains %d\n",
+ sl->tx_cnt, remains);
+
+ clear_bit(SLF_TXBUFF_INPR, &sl->flags);
+ smp_mb__after_clear_bit();
+
+ } while (unlikely(test_bit(SLF_TXBUFF_RQ, &sl->flags)));
+
+ return 0;
+
+error_in_write:
+ clear_bit(SLF_TXBUFF_INPR, &sl->flags);
+ return -1;
+
+}
+
+#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;
+ int retval;
+ unsigned long break_baud;
+ unsigned long usleep_range_min;
+ unsigned long usleep_range_max;
+
+ break_baud = ((sl->lin_baud * 2) / 3);
+ 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_min = (1000000l * SLLIN_SAMPLES_PER_CHAR) / break_baud;
+ usleep_range_max = usleep_range_min + 50;
+ usleep_range(usleep_range_min, usleep_range_max);
+
+ retval = tty->ops->break_ctl(tty, 0);
+ usleep_range_min = (1000000l * 1 /* 1 bit */) / break_baud;
+ usleep_range_max = usleep_range_min + 30;
+ usleep_range(usleep_range_min, usleep_range_max);
+
+ tty->ops->flush_buffer(tty);
+
+ sl->tx_cnt = SLLIN_BUFF_SYNC;
+
+ pr_debug("sllin: Break sent.\n");
+ set_bit(SLF_RXEVENT, &sl->flags);
+ wake_up(&sl->kwt_wq);
+
+ return 0;
+}
+#endif /* BREAK_BY_BAUD */
+
+
+static enum hrtimer_restart sllin_rx_timeout_handler(struct hrtimer *hrtimer)
+{
+ struct sllin *sl = container_of(hrtimer, struct sllin, rx_timer);
+
+ 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)
+{
+ unsigned long flags;
+ int actual_id;
+ int ext_chcks_fl;
+ int lin_dlc;
+ unsigned char rec_chcksm = sl->rx_buff[sl->rx_cnt - 1];
+ struct sllin_conf_entry *sce;
+
+ actual_id = sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK;
+ sce = &sl->linfr_cache[actual_id];
+
+ spin_lock_irqsave(&sl->linfr_lock, flags);
+ lin_dlc = sce->dlc;
+ ext_chcks_fl = sce->frame_fl & LIN_CHECKSUM_EXTENDED;
+ spin_unlock_irqrestore(&sl->linfr_lock, flags);
+
+ if (sllin_checksum(sl->rx_buff, sl->rx_cnt - 1, ext_chcks_fl) !=
+ rec_chcksm) {
+
+ /* Type of checksum is configured for particular frame */
+ if (lin_dlc > 0) {
+ return -1;
+ } else {
+ if (sllin_checksum(sl->rx_buff, sl->rx_cnt - 1,
+ !ext_chcks_fl) != rec_chcksm) {
+ return -1;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*****************************************
+ * 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 tx_bytes = 0; /* Used for Network statistics */
+
+
+ pr_debug("sllin: sllin_kwthread started.\n");
+ sched_setscheduler(current, SCHED_FIFO, &schparam);
+
+ clear_bit(SLF_ERROR, &sl->flags);
+ sltty_change_speed(tty, sl->lin_baud);
+
+ while (!kthread_should_stop()) {
+ struct can_frame *cf;
+ u8 *lin_data;
+ int lin_dlc;
+ u8 lin_data_buff[SLLIN_DATA_MAX];
+
+
+ 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) ||
+ 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)));
+
+ if (test_and_clear_bit(SLF_RXEVENT, &sl->flags)) {
+ 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");
+ sllin_reset_buffs(sl);
+
+ sl->lin_state = SLSTATE_IDLE;
+ }
+
+ switch (sl->lin_state) {
+ case SLSTATE_IDLE:
+ if (!test_bit(SLF_MSGEVENT, &sl->flags))
+ break;
+
+ cf = (struct can_frame *)sl->tx_req_skb->data;
+
+ /* SFF RTR CAN frame -> LIN header */
+ if (cf->can_id & CAN_RTR_FLAG) {
+ unsigned long flags;
+ struct sllin_conf_entry *sce;
+
+ pr_debug("sllin: %s: RTR SFF CAN frame, ID = %x\n",
+ __func__, cf->can_id & LIN_ID_MASK);
+
+ sce = &sl->linfr_cache[cf->can_id & LIN_ID_MASK];
+ spin_lock_irqsave(&sl->linfr_lock, flags);
+
+ /* Is there Slave response in linfr_cache to be sent? */
+ if ((sce->frame_fl & LIN_CACHE_RESPONSE)
+ && (sce->dlc > 0)) {
+
+ pr_debug("sllin: Sending LIN response from linfr_cache\n");
+
+ lin_data = sce->data;
+ lin_dlc = sce->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 = sce->dlc;
+ }
+ spin_unlock_irqrestore(&sl->linfr_lock, flags);
+
+ } else { /* SFF NON-RTR CAN frame -> LIN header + LIN response */
+ pr_debug("sllin: %s: NON-RTR SFF CAN frame, ID = %x\n",
+ __func__, (int)cf->can_id & LIN_ID_MASK);
+
+ lin_data = cf->data;
+ lin_dlc = cf->can_dlc;
+ if (lin_dlc > SLLIN_DATA_MAX)
+ lin_dlc = SLLIN_DATA_MAX;
+ tx_bytes = lin_dlc;
+ }
+
+ if (sllin_setup_msg(sl, 0, cf->can_id & LIN_ID_MASK,
+ lin_data, lin_dlc) != -1) {
+
+ sl->id_to_send = true;
+ sl->data_to_send = (lin_data != NULL) ? true : false;
+ sl->resp_len_known = (lin_dlc > 0) ? true : false;
+ sl->dev->stats.tx_packets++;
+ sl->dev->stats.tx_bytes += tx_bytes;
+ }
+
+ clear_bit(SLF_MSGEVENT, &sl->flags);
+ kfree_skb(sl->tx_req_skb);
+ netif_wake_queue(sl->dev);
+ hrtimer_start(&sl->rx_timer,
+ ktime_add(ktime_get(), sl->rx_timer_timeout),
+ HRTIMER_MODE_ABS);
+ break;
+
+ case SLSTATE_BREAK_SENT:
+#ifdef BREAK_BY_BAUD
+ if (sl->rx_cnt <= SLLIN_BUFF_BREAK)
+ continue;
+
+ 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:
+ hrtimer_cancel(&sl->rx_timer);
+ sl->id_to_send = false;
+ if (sl->data_to_send) {
+ sllin_send_tx_buff(sl);
+ sl->lin_state = SLSTATE_RESPONSE_SENT;
+ sl->rx_expect = sl->tx_lim;
+ goto slstate_response_sent;
+ } else {
+ if (sl->resp_len_known) {
+ sl->rx_expect = sl->rx_lim;
+ } else {
+ sl->rx_expect = SLLIN_BUFF_DATA + 2;
+ }
+ sl->lin_state = SLSTATE_RESPONSE_WAIT;
+ /* If we don't receive anything, timer will "unblock" us */
+ hrtimer_start(&sl->rx_timer,
+ ktime_add(ktime_get(), sl->rx_timer_timeout),
+ HRTIMER_MODE_ABS);
+ goto slstate_response_wait;
+ }
+ break;
+
+ case SLSTATE_RESPONSE_WAIT:
+slstate_response_wait:
+ if (test_bit(SLF_MSGEVENT, &sl->flags)) {
+ unsigned char *lin_buff;
+ 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] & LIN_ID_MASK)) {
+ hrtimer_cancel(&sl->rx_timer);
+ pr_debug("sllin: received LIN response in a CAN frame.\n");
+ if (sllin_setup_msg(sl, SLLIN_STPMSG_RESPONLY,
+ cf->can_id & LIN_ID_MASK,
+ cf->data, cf->can_dlc) != -1) {
+
+ sl->rx_expect = sl->tx_lim;
+ sl->data_to_send = true;
+ sl->dev->stats.tx_packets++;
+ sl->dev->stats.tx_bytes += tx_bytes;
+
+ if (!sl->lin_master) {
+ sl->tx_cnt = SLLIN_BUFF_DATA;
+ }
+
+ sllin_send_tx_buff(sl);
+ clear_bit(SLF_MSGEVENT, &sl->flags);
+ kfree_skb(sl->tx_req_skb);
+ netif_wake_queue(sl->dev);
+
+ sl->lin_state = SLSTATE_RESPONSE_SENT;
+ goto slstate_response_sent;
+ }
+ } else {
+ sl->lin_state = SLSTATE_RESPONSE_WAIT_BUS;
+ }
+ }
+
+ /* Be aware, no BREAK here */
+ case SLSTATE_RESPONSE_WAIT_BUS:
+ if (sl->rx_cnt < sl->rx_expect)
+ continue;
+
+ hrtimer_cancel(&sl->rx_timer);
+ 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) {
+ pr_debug("sllin: RX validation failed.\n");
+ sllin_report_error(sl, LIN_ERR_CHECKSUM);
+ } else {
+ /* Send CAN non-RTR frame with data */
+ pr_debug("sllin: sending NON-RTR CAN frame with LIN payload.");
+ sll_bump(sl); /* send packet to the network layer */
+ }
+
+ sl->id_to_send = false;
+ sl->lin_state = SLSTATE_IDLE;
+ break;
+
+ case SLSTATE_RESPONSE_SENT:
+slstate_response_sent:
+ 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);
+
+ sl->id_to_send = false;
+ sl->lin_state = SLSTATE_IDLE;
+ break;
+ }
+ }
+
+ hrtimer_cancel(&sl->rx_timer);
+ pr_debug("sllin: sllin_kwthread stopped.\n");
+
+ return 0;
+}
+
+
/************************************
- * slcan_open helper routines.
+ * sllin_open helper routines.
************************************/
/* Collect hanged up channels */
-static void slc_sync(void)
+static void sll_sync(void)
{
int i;
struct net_device *dev;
- struct slcan *sl;
+ struct sllin *sl;
for (i = 0; i < maxdev; i++) {
- dev = slcan_devs[i];
+ dev = sllin_devs[i];
if (dev == NULL)
break;
sl = netdev_priv(dev);
- if (sl->tty || sl->leased)
+ if (sl->tty)
continue;
if (dev->flags & IFF_UP)
dev_close(dev);
}
}
-/* Find a free SLCAN channel, and link in this `tty' line. */
-static struct slcan *slc_alloc(dev_t line)
+/* Find a free SLLIN channel, and link in this `tty' line. */
+static struct sllin *sll_alloc(dev_t line)
{
int i;
struct net_device *dev = NULL;
- struct slcan *sl;
+ struct sllin *sl;
- if (slcan_devs == NULL)
+ if (sllin_devs == NULL)
return NULL; /* Master array missing ! */
for (i = 0; i < maxdev; i++) {
- dev = slcan_devs[i];
+ dev = sllin_devs[i];
if (dev == NULL)
break;
if (test_bit(SLF_INUSE, &sl->flags)) {
unregister_netdevice(dev);
dev = NULL;
- slcan_devs[i] = NULL;
+ sllin_devs[i] = NULL;
}
}
if (!dev) {
char name[IFNAMSIZ];
- sprintf(name, "slcan%d", i);
+ sprintf(name, "sllin%d", i);
- dev = alloc_netdev(sizeof(*sl), name, slc_setup);
+ dev = alloc_netdev(sizeof(*sl), name, sll_setup);
if (!dev)
return NULL;
dev->base_addr = i;
}
sl = netdev_priv(dev);
-
/* Initialize channel control data */
- sl->magic = SLCAN_MAGIC;
+ sl->magic = SLLIN_MAGIC;
sl->dev = dev;
spin_lock_init(&sl->lock);
- slcan_devs[i] = dev;
+ spin_lock_init(&sl->linfr_lock);
+ sllin_devs[i] = dev;
return sl;
}
/*
- * Open the high-level part of the SLCAN channel.
+ * Open the high-level part of the SLLIN channel.
* This function is called by the TTY module when the
- * SLCAN line discipline is called for. Because we are
+ * SLLIN line discipline is called for. Because we are
* sure the tty line exists, we only have to link it to
- * a free SLCAN channel...
+ * a free SLLIN channel...
*
* Called in process context serialized from other ldisc calls.
*/
-static int slcan_open(struct tty_struct *tty)
+static int sllin_open(struct tty_struct *tty)
{
- struct slcan *sl;
+ struct sllin *sl;
int err;
+ pr_debug("sllin: %s() invoked\n", __func__);
if (!capable(CAP_NET_ADMIN))
return -EPERM;
return -EOPNOTSUPP;
/* RTnetlink lock is misused here to serialize concurrent
- opens of slcan channels. There are better ways, but it is
+ opens of sllin channels. There are better ways, but it is
the simplest one.
*/
rtnl_lock();
/* Collect hanged up channels. */
- slc_sync();
+ sll_sync();
sl = tty->disc_data;
err = -EEXIST;
/* First make sure we're not already connected. */
- if (sl && sl->magic == SLCAN_MAGIC)
+ if (sl && sl->magic == SLLIN_MAGIC)
goto err_exit;
- /* OK. Find a free SLCAN channel to use. */
+ /* OK. Find a free SLLIN channel to use. */
err = -ENFILE;
- sl = slc_alloc(tty_devnum(tty));
+ sl = sll_alloc(tty_devnum(tty));
if (sl == NULL)
goto err_exit;
sl->tty = tty;
tty->disc_data = sl;
sl->line = tty_devnum(tty);
- sl->pid = current->pid;
if (!test_bit(SLF_INUSE, &sl->flags)) {
- /* Perform the low-level SLCAN initialization. */
- sl->rcount = 0;
- sl->xleft = 0;
+ /* Perform the low-level SLLIN initialization. */
+ sl->lin_master = master;
+#ifdef DEBUG
+ if (master)
+ pr_debug("sllin: Configured as MASTER\n");
+ else
+ pr_debug("sllin: Configured as SLAVE\n");
+#endif
+
+ sllin_reset_buffs(sl);
+
+ 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;
+
+ hrtimer_init(&sl->rx_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ sl->rx_timer.function = sllin_rx_timeout_handler;
+ /* timeval_to_ktime(msg_head->ival1); */
+ sl->rx_timer_timeout = ns_to_ktime(
+ (1000000000l / sl->lin_baud) *
+ SLLIN_SAMPLES_PER_CHAR * SLLIN_CHARS_TO_TIMEOUT);
set_bit(SLF_INUSE, &sl->flags);
+ init_waitqueue_head(&sl->kwt_wq);
+ sl->kwthread = kthread_run(sllin_kwthread, sl, "sllin");
+ if (sl->kwthread == NULL)
+ goto err_free_chan;
+
err = register_netdevice(sl->dev);
if (err)
- goto err_free_chan;
+ goto err_free_chan_and_thread;
}
/* Done. We have linked the TTY line to a channel. */
rtnl_unlock();
- tty->receive_room = 65536; /* We don't flow control */
+ tty->receive_room = SLLIN_BUFF_LEN * 40; /* We don't flow control */
/* TTY layer expects 0 on success */
return 0;
+err_free_chan_and_thread:
+ kthread_stop(sl->kwthread);
+ sl->kwthread = NULL;
+
err_free_chan:
sl->tty = NULL;
tty->disc_data = NULL;
}
/*
- * Close down a SLCAN channel.
+ * Close down a SLLIN channel.
* This means flushing out any pending queues, and then returning. This
* call is serialized against other ldisc functions.
*
* We also use this method for a hangup event.
*/
-static void slcan_close(struct tty_struct *tty)
+static void sllin_close(struct tty_struct *tty)
{
- struct slcan *sl = (struct slcan *) tty->disc_data;
+ struct sllin *sl = (struct sllin *) tty->disc_data;
/* First make sure we're connected. */
- if (!sl || sl->magic != SLCAN_MAGIC || sl->tty != tty)
+ if (!sl || sl->magic != SLLIN_MAGIC || sl->tty != tty)
return;
+ kthread_stop(sl->kwthread);
+ sl->kwthread = NULL;
+
tty->disc_data = NULL;
sl->tty = NULL;
- if (!sl->leased)
- sl->line = 0;
/* Flush network side */
unregister_netdev(sl->dev);
/* This will complete via sl_free_netdev */
}
-static int slcan_hangup(struct tty_struct *tty)
+static int sllin_hangup(struct tty_struct *tty)
{
- slcan_close(tty);
+ sllin_close(tty);
return 0;
}
-/* Perform I/O control on an active SLCAN channel. */
-static int slcan_ioctl(struct tty_struct *tty, struct file *file,
+/* Perform I/O control on an active SLLIN channel. */
+static int sllin_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
- struct slcan *sl = (struct slcan *) tty->disc_data;
+ struct sllin *sl = (struct sllin *) tty->disc_data;
unsigned int tmp;
/* First make sure we're connected. */
- if (!sl || sl->magic != SLCAN_MAGIC)
+ if (!sl || sl->magic != SLLIN_MAGIC)
return -EINVAL;
switch (cmd) {
}
}
-static struct tty_ldisc_ops slc_ldisc = {
+static struct tty_ldisc_ops sll_ldisc = {
.owner = THIS_MODULE,
.magic = TTY_LDISC_MAGIC,
- .name = "slcan",
- .open = slcan_open,
- .close = slcan_close,
- .hangup = slcan_hangup,
- .ioctl = slcan_ioctl,
- .receive_buf = slcan_receive_buf,
- .write_wakeup = slcan_write_wakeup,
+ .name = "sllin",
+ .open = sllin_open,
+ .close = sllin_close,
+ .hangup = sllin_hangup,
+ .ioctl = sllin_ioctl,
+ .receive_buf = sllin_receive_buf,
+ .write_wakeup = sllin_write_wakeup,
};
-static int __init slcan_init(void)
+static int __init sllin_init(void)
{
int status;
maxdev = 4; /* Sanity */
printk(banner);
- printk(KERN_INFO "slcan: %d dynamic interface channels.\n", maxdev);
+ pr_debug("sllin: %d dynamic interface channels.\n", maxdev);
- slcan_devs = kzalloc(sizeof(struct net_device *)*maxdev, GFP_KERNEL);
- if (!slcan_devs) {
- printk(KERN_ERR "slcan: can't allocate slcan device array!\n");
+ sllin_devs = kzalloc(sizeof(struct net_device *)*maxdev, GFP_KERNEL);
+ if (!sllin_devs) {
+ pr_err("sllin: can't allocate sllin device array!\n");
return -ENOMEM;
}
/* Fill in our line protocol discipline, and register it */
- status = tty_register_ldisc(N_SLCAN, &slc_ldisc);
+ status = tty_register_ldisc(N_SLLIN, &sll_ldisc);
if (status) {
- printk(KERN_ERR "slcan: can't register line discipline\n");
- kfree(slcan_devs);
+ pr_err("sllin: can't register line discipline\n");
+ kfree(sllin_devs);
}
+
+#ifdef BREAK_BY_BAUD
+ pr_debug("sllin: Break is generated by baud-rate change.");
+#else
+ pr_debug("sllin: Break is generated manually with tiny sleep.");
+#endif
+
return status;
}
-static void __exit slcan_exit(void)
+static void __exit sllin_exit(void)
{
int i;
struct net_device *dev;
- struct slcan *sl;
+ struct sllin *sl;
unsigned long timeout = jiffies + HZ;
int busy = 0;
- if (slcan_devs == NULL)
+ if (sllin_devs == NULL)
return;
/* First of all: check for active disciplines and hangup them.
busy = 0;
for (i = 0; i < maxdev; i++) {
- dev = slcan_devs[i];
+ dev = sllin_devs[i];
if (!dev)
continue;
sl = netdev_priv(dev);
phase */
for (i = 0; i < maxdev; i++) {
- dev = slcan_devs[i];
+ dev = sllin_devs[i];
if (!dev)
continue;
- slcan_devs[i] = NULL;
+ sllin_devs[i] = NULL;
sl = netdev_priv(dev);
if (sl->tty) {
- printk(KERN_ERR "%s: tty discipline still running\n",
+ pr_err("%s: tty discipline still running\n",
dev->name);
/* Intentionally leak the control block. */
dev->destructor = NULL;
unregister_netdev(dev);
}
- kfree(slcan_devs);
- slcan_devs = NULL;
+ kfree(sllin_devs);
+ sllin_devs = NULL;
- i = tty_unregister_ldisc(N_SLCAN);
+ i = tty_unregister_ldisc(N_SLLIN);
if (i)
- printk(KERN_ERR "slcan: can't unregister ldisc (err %d)\n", i);
+ pr_err("sllin: can't unregister ldisc (err %d)\n", i);
}
-module_init(slcan_init);
-module_exit(slcan_exit);
+module_init(sllin_init);
+module_exit(sllin_exit);