X-Git-Url: http://rtime.felk.cvut.cz/gitweb/linux-lin.git/blobdiff_plain/3a009025af041a40c8e88be5f23203727d7abc22..e2414b4fbb15520fe38c8319e5fb7c3fe5e1b679:/sllin/sllin.c diff --git a/sllin/sllin.c b/sllin/sllin.c index 1b49df6..3e020b1 100644 --- a/sllin/sllin.c +++ b/sllin/sllin.c @@ -1,11 +1,8 @@ /* - * 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 - * Fred N. van Kempen - * slcan.c Author : Oliver Hartkopp + * This file is derived from drivers/net/can/slcan.c + * slcan.c Author: Oliver Hartkopp * * 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 @@ -35,14 +32,20 @@ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH * DAMAGE. * - * Send feedback to - * + * Idea: Oliver Hartkopp + * Copyright: (c) 2011 Czech Technical University in Prague + * (c) 2011 Volkswagen Group Research + * Authors: Pavel Pisa + * Rostislav Lisovy + * Michal Sojka + * Funded by: Volkswagen Group Research */ +#define DEBUG 1 /* Enables pr_debug() printouts */ + #include #include -#include #include #include #include @@ -57,27 +60,71 @@ #include #include #include +#include +#include +#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 "); +MODULE_AUTHOR("Pavel Pisa "); + +#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_ID_RECEIVED, + 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. */ @@ -85,127 +132,117 @@ struct slcan { 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 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: - * * - * - * 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 is 3 (standard) or 8 (extended) bytes in ASCII Hex (base64). - * The is a one byte ASCII number ('0' - '8') - * The section has at much ASCII Hex bytes as defined by the - * - * 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); + + 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 >= '0') && (c <= '9')) - return c - '0'; + /* 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); - if ((c >= 'a') && (c <= 'f')) - return c - 'a' + 10; + if (tty->ops->set_termios) + tty->ops->set_termios(tty, &old_termios); - return 16; /* error */ + 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) @@ -223,124 +260,120 @@ static void slc_bump(struct slcan *sl) 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)) { + netdev_dbg(sl->dev, "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); + + netdev_dbg(sl->dev, "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; + netdev_warn(sl->dev, "xmit: iface is down\n"); + goto err_out_unlock; } if (sl->tty == NULL) { - spin_unlock(&sl->lock); - goto out; + netdev_warn(sl->dev, "xmit: no tty device connected\n"); + 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; } @@ -351,9 +384,9 @@ out: ******************************************/ /* 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) { @@ -361,17 +394,19 @@ static int slc_close(struct net_device *dev) 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); + + netdev_dbg(sl->dev, "%s() invoked\n", __func__); if (sl->tty == NULL) return -ENODEV; @@ -381,24 +416,24 @@ static int slc_open(struct net_device *dev) 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; @@ -409,78 +444,856 @@ static void slc_setup(struct net_device *dev) /* 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++) { + netdev_dbg(sl->dev, "sllin_master_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)) { + netdev_dbg(sl->dev, "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) { + netdev_dbg(sl->dev, "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); + netdev_dbg(sl->dev, "sllin_receive_buf count %d, wakeup\n", sl->rx_cnt); + } else { + netdev_dbg(sl->dev, "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. + */ +static 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]; + netdev_dbg(sl->dev, "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; -static void slcan_receive_buf(struct tty_struct *tty, + 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) + +static 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; +} + +/** + * 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; +} + +static void sllin_slave_finish_rx_msg(struct sllin *sl) +{ + if (sllin_rx_validate(sl) == -1) { + netdev_dbg(sl->dev, "sllin: RX validation failed.\n"); + sllin_report_error(sl, LIN_ERR_CHECKSUM); + } else { + /* Send CAN non-RTR frame with data */ + netdev_dbg(sl->dev, "sllin: sending NON-RTR CAN frame with LIN payload."); + sll_bump(sl); /* send packet to the network layer */ + } + /* 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_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++; + /* + * If we don't know the length of the current message + * we received the break of the next message. + * Evaluate the previous one before continuing + */ + if (sl->rx_len_unknown == true) + { + hrtimer_cancel(&sl->rx_timer); + sllin_slave_finish_rx_msg(sl); + + set_bit(SLF_RXEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + } + + netdev_dbg(sl->dev, "sllin_slave_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) { + netdev_dbg(sl->dev, "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); + + sl->lin_state = SLSTATE_ID_RECEIVED; + /* Is the length of data set in frame cache? */ + if (sce->frame_fl & LIN_CACHE_RESPONSE) { + sl->rx_expect += sce->dlc + 1; /* + checksum */ + sl->rx_len_unknown = false; + set_bit(SLF_MSGEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + } 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; + + hrtimer_start(&sl->rx_timer, + ktime_add(ktime_get(), sl->rx_timer_timeout), + HRTIMER_MODE_ABS); + sll_send_rtr(sl); continue; } - slcan_unesc(sl, *cp++); + + /* Response received */ + if ((sl->header_received == true) && + ((sl->rx_cnt >= sl->rx_expect))) { + + hrtimer_cancel(&sl->rx_timer); + netdev_dbg(sl->dev, "Received LIN header & LIN response. " + "rx_cnt = %u, rx_expect = %u\n", sl->rx_cnt, + sl->rx_expect); + sllin_slave_finish_rx_msg(sl); + + set_bit(SLF_RXEVENT, &sl->flags); + wake_up(&sl->kwt_wq); + } + } +} + +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; + netdev_dbg(sl->dev, "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); + +} + +static 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; + } + + netdev_dbg(sl->dev, "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 +static 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 */ + +static 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; + + netdev_dbg(sl->dev, "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); + + if (sl->lin_master) { + sllin_report_error(sl, LIN_ERR_RX_TIMEOUT); + set_bit(SLF_TMOUTEVENT, &sl->flags); + } else { + sllin_slave_finish_rx_msg(sl); + set_bit(SLF_RXEVENT, &sl->flags); + } + wake_up(&sl->kwt_wq); + + return HRTIMER_NORESTART; +} + +/***************************************** + * sllin_kwthread - kernel worker thread + *****************************************/ + +static 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 */ + unsigned long flags; + int lin_id; + struct sllin_conf_entry *sce; + + netdev_dbg(sl->dev, "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) || + (sl->lin_state == SLSTATE_ID_RECEIVED)) + && test_bit(SLF_MSGEVENT, &sl->flags))); + + if (test_and_clear_bit(SLF_RXEVENT, &sl->flags)) { + netdev_dbg(sl->dev, "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); + netdev_dbg(sl->dev, "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)) { + netdev_dbg(sl->dev, "sllin_kthread TXEVENT\n"); + } + + if (test_and_clear_bit(SLF_TMOUTEVENT, &sl->flags)) { + netdev_dbg(sl->dev, "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) { + struct sllin_conf_entry *sce; + + netdev_dbg(sl->dev, "%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)) { + + netdev_dbg(sl->dev, "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 */ + netdev_dbg(sl->dev, "%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); + netdev_dbg(sl->dev, "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); + netdev_dbg(sl->dev, "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) { + netdev_dbg(sl->dev, "RX validation failed.\n"); + sllin_report_error(sl, LIN_ERR_CHECKSUM); + } else { + /* Send CAN non-RTR frame with data */ + netdev_dbg(sl->dev, "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_ID_RECEIVED: + lin_id = sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK; + sce = &sl->linfr_cache[lin_id]; + spin_lock_irqsave(&sl->linfr_lock, flags); + + if ((sce->frame_fl & LIN_CACHE_RESPONSE) + && (sce->dlc > 0) + && (test_bit(SLF_MSGEVENT, &sl->flags))) { + int mode; + + netdev_dbg(sl->dev, "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; + tx_bytes = lin_dlc; + + mode = SLLIN_STPMSG_RESPONLY; + if (sl->rx_buff[SLLIN_BUFF_ID] & LIN_CHECKSUM_EXTENDED) + mode |= SLLIN_STPMSG_CHCKSUM_ENH; + + if (sllin_setup_msg(sl, mode, lin_id & LIN_ID_MASK, + lin_data, lin_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; + sl->resp_len_known = true; + + 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); + hrtimer_start(&sl->rx_timer, + ktime_add(ktime_get(), sl->rx_timer_timeout), + HRTIMER_MODE_ABS); + } + spin_unlock_irqrestore(&sl->linfr_lock, flags); + 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 */ + netdev_dbg(sl->dev, "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); + netdev_dbg(sl->dev, "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; @@ -495,46 +1308,48 @@ static struct slcan *slc_alloc(dev_t line) 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; @@ -542,51 +1357,76 @@ static int slcan_open(struct tty_struct *tty) 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; + if (master) + pr_debug("sllin: Configured as MASTER\n"); + else + pr_debug("sllin: Configured as SLAVE\n"); + + 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; @@ -600,46 +1440,47 @@ err_exit: } /* - * 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) { @@ -657,19 +1498,19 @@ static int slcan_ioctl(struct tty_struct *tty, struct file *file, } } -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; @@ -677,32 +1518,39 @@ static int __init slcan_init(void) 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. @@ -713,7 +1561,7 @@ static void __exit slcan_exit(void) busy = 0; for (i = 0; i < maxdev; i++) { - dev = slcan_devs[i]; + dev = sllin_devs[i]; if (!dev) continue; sl = netdev_priv(dev); @@ -730,15 +1578,14 @@ static void __exit slcan_exit(void) 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", - dev->name); + netdev_dbg(sl->dev, "tty discipline still running\n"); /* Intentionally leak the control block. */ dev->destructor = NULL; } @@ -746,13 +1593,13 @@ static void __exit slcan_exit(void) 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);