X-Git-Url: http://rtime.felk.cvut.cz/gitweb/linux-lin.git/blobdiff_plain/a90f90f84ad111cc035a6c4bdcef31df047e9ce0..080feeb899d8630a9314a3f44bcf93434626543a:/sllin/sllin.c diff --git a/sllin/sllin.c b/sllin/sllin.c index d6cc0f0..528d746 100644 --- a/sllin/sllin.c +++ b/sllin/sllin.c @@ -36,6 +36,8 @@ * */ +#define DEBUG 1 /* Enables pr_debug() printouts */ + #include #include @@ -56,9 +58,11 @@ #include #include #include +#include "linux/lin_bus.h" /* Should be in include/linux/tty.h */ -#define N_SLLIN 25 +#define N_SLLIN 25 +/* -------------------------------- */ static __initdata const char banner[] = KERN_INFO "sllin: serial line LIN interface driver\n"; @@ -68,8 +72,8 @@ MODULE_DESCRIPTION("serial line LIN interface"); MODULE_LICENSE("GPL"); MODULE_AUTHOR(""); -#define SLLIN_MAGIC 0x53CA -// #define BREAK_BY_BAUD +#define SLLIN_MAGIC 0x53CA +/* #define BREAK_BY_BAUD */ static int maxdev = 10; /* MAX number of SLLIN channels; This can be overridden with @@ -78,43 +82,32 @@ module_param(maxdev, int, 0); MODULE_PARM_DESC(maxdev, "Maximum number of sllin interfaces"); /* maximum buffer len to store whole LIN message*/ -#define SLLIN_DATA_MAX 8 -#define SLLIN_BUFF_LEN (1 /*break*/ + 1 /*sync*/ + 1 /*ID*/ + \ - SLLIN_DATA_MAX + 1 /*checksum*/) -#define SLLIN_BUFF_BREAK 0 -#define SLLIN_BUFF_SYNC 1 -#define SLLIN_BUFF_ID 2 -#define SLLIN_BUFF_DATA 3 - -#define SLLIN_ID_MASK 0x3f -#define SLLIN_ID_MAX SLLIN_ID_MASK -#define SLLIN_STATUS_FLAG SLLIN_EFF_FLAG +#define SLLIN_DATA_MAX 8 +#define SLLIN_BUFF_LEN (1 /*break*/ + 1 /*sync*/ + 1 /*ID*/ + \ + SLLIN_DATA_MAX + 1 /*checksum*/) +#define SLLIN_BUFF_BREAK 0 +#define SLLIN_BUFF_SYNC 1 +#define SLLIN_BUFF_ID 2 +#define SLLIN_BUFF_DATA 3 + +#define SLLIN_SAMPLES_PER_CHAR 10 +#define SLLIN_CHARS_TO_TIMEOUT 24 enum slstate { SLSTATE_IDLE = 0, SLSTATE_BREAK_SENT, SLSTATE_ID_SENT, - SLSTATE_RESPONSE_WAIT, + 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, }; struct sllin_conf_entry { int dlc; /* Length of data in LIN frame */ -#define SLLIN_CANFR_FLAGS_OFFS 6 /* Lower 6 bits in can_id correspond to LIN ID */ -/* Save configuration for particualr LIN ID */ -#define SLLIN_LIN_ID_CONF (1 << SLLIN_CANFR_FLAGS_OFFS) -/* Publisher of particular LIN response is SLLIN Master */ -#define SLLIN_SRC_MASTER (1 << (SLLIN_CANFR_FLAGS_OFFS + 1)) -#define SLLIN_SRC_SLAVE (1 << (SLLIN_CANFR_FLAGS_OFFS + 2)) -#define SLLIN_SLAVE_LOCAL (1 << (SLLIN_CANFR_FLAGS_OFFS + 3)) -#define SLLIN_SLAVE_REMOTE (1 << (SLLIN_CANFR_FLAGS_OFFS + 4)) -#define SLLIN_LOC_SLAVE_CACHE (1 << (SLLIN_CANFR_FLAGS_OFFS + 5)) - -#define SLLIN_ERR_RX_TIMEOUT (1 << (SLLIN_CANFR_FLAGS_OFFS + 6)) -#define SLLIN_ERR_CHECKSUM (1 << (SLLIN_CANFR_FLAGS_OFFS + 7)) -//#define SLLIN_ERR_FRAMING (1 << (SLLIN_CANFR_FLAGS_OFFS + 8)) - - canid_t frame_fl; /* LIN frame flags. Passed from userspace as canid_t data type */ + canid_t frame_fl; /* LIN frame flags. Passed from userspace as + canid_t data type */ u8 data[8]; /* LIN frame data payload */ }; @@ -139,6 +132,7 @@ struct sllin { 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 */ unsigned long flags; /* Flag values/ mode etc */ #define SLF_INUSE 0 /* Channel in use */ @@ -150,28 +144,42 @@ struct sllin { dev_t line; struct task_struct *kwthread; - wait_queue_head_t kwt_wq; + wait_queue_head_t kwt_wq; /* Wait queue used by kwthread */ struct hrtimer rx_timer; /* RX timeout timer */ ktime_t rx_timer_timeout; /* RX timeout timer value */ - struct sk_buff *rec_skb; /* Socket buffer with received CAN frame */ + struct sk_buff *tx_req_skb; /* Socket buffer with CAN frame + received from network stack*/ - struct sllin_conf_entry linfr_cache[SLLIN_ID_MAX + 1]; /* List with configurations for - each of 0 to SLLIN_ID_MAX LIN IDs */ + /* List with configurations for each of 0 to LIN_ID_MAX LIN IDs */ + struct sllin_conf_entry linfr_cache[LIN_ID_MAX + 1]; }; static struct net_device **sllin_devs; +static int sllin_configure_frame_cache(struct sllin *sl, struct can_frame *cf); + +/* Values of two parity bits in LIN Protected + Identifier for each particular LIN ID */ const unsigned char sllin_id_parity_table[] = { - 0x80,0xc0,0x40,0x00,0xc0,0x80,0x00,0x40, - 0x00,0x40,0xc0,0x80,0x40,0x00,0x80,0xc0, - 0x40,0x00,0x80,0xc0,0x00,0x40,0xc0,0x80, - 0xc0,0x80,0x00,0x40,0x80,0xc0,0x40,0x00, - 0x00,0x40,0xc0,0x80,0x40,0x00,0x80,0xc0, - 0x80,0xc0,0x40,0x00,0xc0,0x80,0x00,0x40, - 0xc0,0x80,0x00,0x40,0x80,0xc0,0x40,0x00, - 0x40,0x00,0x80,0xc0,0x00,0x40,0xc0,0x80 + 0x80, 0xc0, 0x40, 0x00, 0xc0, 0x80, 0x00, 0x40, + 0x00, 0x40, 0xc0, 0x80, 0x40, 0x00, 0x80, 0xc0, + 0x40, 0x00, 0x80, 0xc0, 0x00, 0x40, 0xc0, 0x80, + 0xc0, 0x80, 0x00, 0x40, 0x80, 0xc0, 0x40, 0x00, + 0x00, 0x40, 0xc0, 0x80, 0x40, 0x00, 0x80, 0xc0, + 0x80, 0xc0, 0x40, 0x00, 0xc0, 0x80, 0x00, 0x40, + 0xc0, 0x80, 0x00, 0x40, 0x80, 0xc0, 0x40, 0x00, + 0x40, 0x00, 0x80, 0xc0, 0x00, 0x40, 0xc0, 0x80 }; +/** + * sltty_change_speed() -- Change baudrate of Serial device belonging + * to particular @tty + * + * @tty: Pointer to TTY to change speed for. + * @speed: Integer value of new speed. It is possible to + * assign non-standard values, i.e. those which + * are not defined in termbits.h. + */ static int sltty_change_speed(struct tty_struct *tty, unsigned speed) { struct ktermios old_termios; @@ -180,10 +188,16 @@ static int sltty_change_speed(struct tty_struct *tty, unsigned speed) mutex_lock(&tty->termios_mutex); old_termios = *(tty->termios); - cflag = tty->termios->c_cflag; + + 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; + + /* Enable interrupt when UART-Break or Framing error received */ + tty->termios->c_iflag = BRKINT | INPCK; tty_encode_baud_rate(tty, speed, speed); @@ -195,7 +209,6 @@ static int sltty_change_speed(struct tty_struct *tty, unsigned speed) return 0; } - /* Send one can_frame to the network layer */ static void sllin_send_canfr(struct sllin *sl, canid_t id, char *data, int len) { @@ -222,15 +235,19 @@ static void sllin_send_canfr(struct sllin *sl, canid_t id, char *data, int len) sl->dev->stats.rx_packets++; sl->dev->stats.rx_bytes += cf.can_dlc; - - } +/** + * sll_bump() -- Send data of received LIN frame (existing in sl->rx_buff) + * as CAN frame + * + * @sl: + */ static void sll_bump(struct sllin *sl) { - sllin_send_canfr(sl, sl->rx_buff[SLLIN_BUFF_ID] & SLLIN_ID_MASK, + sllin_send_canfr(sl, sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK, sl->rx_buff + SLLIN_BUFF_DATA, - sl->rx_cnt - SLLIN_BUFF_DATA); + sl->rx_cnt - SLLIN_BUFF_DATA - 1); /* without checksum */ } /* @@ -253,11 +270,13 @@ static void sllin_write_wakeup(struct tty_struct *tty) 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); + actual = tty->ops->write(tty, sl->tx_buff + sl->tx_cnt, + sl->tx_cnt - sl->tx_lim); sl->tx_cnt += actual; if (sl->tx_cnt < sl->tx_lim) { - printk(KERN_INFO "sllin_write_wakeup sent %d, remains %d, waiting\n", + pr_debug("sllin: sllin_write_wakeup sent %d, " + "remains %d, waiting\n", sl->tx_cnt, sl->tx_lim - sl->tx_cnt); return; } @@ -267,36 +286,49 @@ static void sllin_write_wakeup(struct tty_struct *tty) set_bit(SLF_TXEVENT, &sl->flags); wake_up(&sl->kwt_wq); - printk(KERN_INFO "sllin_write_wakeup sent %d, wakeup\n", sl->tx_cnt); + pr_debug("sllin: sllin_write_wakeup sent %d, wakeup\n", sl->tx_cnt); } -/* Send a can_frame to a TTY queue. */ +/** + * sll_xmit() -- Send a can_frame to a TTY queue. + * + * @skb: Pointer to Socket buffer to be sent. + * @dev: Network device where @skb will be sent. + */ static netdev_tx_t sll_xmit(struct sk_buff *skb, struct net_device *dev) { struct sllin *sl = netdev_priv(dev); + struct can_frame *cf; if (skb->len != sizeof(struct can_frame)) 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 err_out; + goto err_out_unlock; } if (sl->tty == NULL) { - spin_unlock(&sl->lock); - goto err_out; + 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); - sl->rec_skb = skb; + sl->tx_req_skb = skb; set_bit(SLF_MSGEVENT, &sl->flags); wake_up(&sl->kwt_wq); spin_unlock(&sl->lock); return NETDEV_TX_OK; +free_out_unlock: +err_out_unlock: + spin_unlock(&sl->lock); err_out: kfree_skb(skb); return NETDEV_TX_OK; @@ -375,21 +407,12 @@ static void sll_setup(struct net_device *dev) Routines looking at TTY side. ******************************************/ -/* - * Handle the 'receiver data ready' interrupt. - * This function is called by the 'tty_io' module in the kernel when - * a block of SLLIN data has been received, which can now be decapsulated - * and sent on to some IP layer for further processing. This will not - * be re-entered while running but other ldisc functions may be called - * in parallel - */ - static void sllin_receive_buf(struct tty_struct *tty, const unsigned char *cp, char *fp, int count) { struct sllin *sl = (struct sllin *) tty->disc_data; - printk(KERN_INFO "sllin_receive_buf invoked\n"); + pr_debug("sllin: sllin_receive_buf invoked\n"); if (!sl || sl->magic != SLLIN_MAGIC || !netif_running(sl->dev)) return; @@ -397,13 +420,21 @@ static void sllin_receive_buf(struct tty_struct *tty, /* 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++; - printk(KERN_INFO "sllin_receive_buf char 0x%02x ignored " - "due marker 0x%02x, flags 0x%lx\n", - *cp, *(fp-1), sl->flags); - cp++; - continue; + if (sl->rx_cnt > SLLIN_BUFF_BREAK) { + set_bit(SLF_ERROR, &sl->flags); + + pr_debug("sllin: sllin_receive_buf char 0x%02x ignored " + "due marker 0x%02x, flags 0x%lx\n", + *cp, *(fp-1), sl->flags); + + if (sl->lin_master == true) { + wake_up(&sl->kwt_wq); + return; + } + + cp++; + continue; + } } if (sl->rx_cnt < SLLIN_BUFF_LEN) { @@ -413,7 +444,7 @@ static void sllin_receive_buf(struct tty_struct *tty, sl->rx_buff[sl->rx_cnt++] = 0x00; } #endif - printk(KERN_INFO "LIN_RX[%d]: 0x%02x\n", sl->rx_cnt, *cp); + pr_debug("sllin: LIN_RX[%d]: 0x%02x\n", sl->rx_cnt, *cp); sl->rx_buff[sl->rx_cnt++] = *cp++; } } @@ -421,48 +452,114 @@ static void sllin_receive_buf(struct tty_struct *tty, if (sl->rx_cnt >= sl->rx_expect) { set_bit(SLF_RXEVENT, &sl->flags); wake_up(&sl->kwt_wq); - printk(KERN_INFO "sllin_receive_buf count %d, wakeup\n", sl->rx_cnt); + pr_debug("sllin: sllin_receive_buf count %d, wakeup\n", sl->rx_cnt); } else { - printk(KERN_INFO "sllin_receive_buf count %d, waiting\n", sl->rx_cnt); + pr_debug("sllin: sllin_receive_buf count %d, waiting\n", sl->rx_cnt); } } /***************************************** * sllin message helper routines *****************************************/ +/** + * sllin_report_error() -- Report an error by sending CAN frame + * with particular error flag set in can_id + * + * @sl: + * @err: Error flag to be sent. + */ void sllin_report_error(struct sllin *sl, int err) { - sllin_send_canfr(sl, 0 | CAN_EFF_FLAG | - (err & ~SLLIN_ID_MASK), NULL, 0); + 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); } -int sllin_configure_frame_cache(struct sllin *sl, struct can_frame *cf) +/** + * sllin_configure_frame_cache() -- Configure particular entry in linfr_cache + * + * @sl: + * @cf: Pointer to CAN frame sent to this driver + * holding configuration information + */ +static int sllin_configure_frame_cache(struct sllin *sl, struct can_frame *cf) { struct sllin_conf_entry *sce; - if (!(cf->can_id & SLLIN_LIN_ID_CONF)) + if (!(cf->can_id & LIN_ID_CONF)) return -1; - sce = &sl->linfr_cache[cf->can_id & SLLIN_ID_MASK]; - printk(KERN_INFO "Setting frame cache with EFF CAN frame. " - "LIN ID = %d\n", cf->can_id & SLLIN_ID_MASK); + sce = &sl->linfr_cache[cf->can_id & LIN_ID_MASK]; + pr_debug("sllin: Setting frame cache with EFF CAN frame. " + "LIN ID = %d\n", cf->can_id & LIN_ID_MASK); + + sce->dlc = cf->can_dlc; + if (sce->dlc > SLLIN_DATA_MAX) + sce->dlc = SLLIN_DATA_MAX; - sce->dlc = (cf->can_dlc > 8) ? 8 : cf->can_dlc; - sce->frame_fl = (cf->can_id & ~SLLIN_ID_MASK) & CAN_EFF_MASK; + sce->frame_fl = (cf->can_id & ~LIN_ID_MASK) & CAN_EFF_MASK; memcpy(sce->data, cf->data, cf->can_dlc); return 0; } +/** + * sllin_checksum() -- Count checksum for particular data + * + * @data: Pointer to the buffer containing whole LIN + * frame (i.e. including break and sync bytes). + * @length: Length of the buffer. + * @enhanced_fl: Flag determining whether Enhanced or Classic + * checksum should be counted. + */ +static inline unsigned sllin_checksum(unsigned char *data, int length, int enhanced_fl) +{ + unsigned csum = 0; + int 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 > SLLIN_ID_MASK) + if (id > LIN_ID_MASK) return -1; - sl->rx_cnt = 0; - sl->tx_cnt = 0; - sl->rx_expect = 0; - sl->rx_lim = SLLIN_BUFF_LEN; + 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; @@ -470,19 +567,10 @@ int sllin_setup_msg(struct sllin *sl, int mode, int id, sl->tx_lim = SLLIN_BUFF_DATA; if ((data != NULL) && len) { - int i; - unsigned csum = 0; - sl->tx_lim += len; memcpy(sl->tx_buff + SLLIN_BUFF_DATA, data, len); - /* compute data parity there */ - for (i = SLLIN_BUFF_DATA; i < sl->tx_lim; i++) { - csum += sl->tx_buff[i]; - if (csum > 255) - csum -= 255; - } - - sl->tx_buff[sl->tx_lim++] = csum; + sl->tx_buff[sl->tx_lim++] = sllin_checksum(sl->tx_buff, + sl->tx_lim, mode & SLLIN_STPMSG_CHCKSUM_ENH); } if (len != 0) sl->rx_lim = SLLIN_BUFF_DATA + len + 1; @@ -490,6 +578,16 @@ int sllin_setup_msg(struct sllin *sl, int mode, int id, 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) { @@ -520,12 +618,12 @@ int sllin_send_tx_buff(struct sllin *sl) clear_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); return -1; } - + remains -= res; sl->tx_cnt += res; } - printk(KERN_INFO "sllin_send_tx_buff sent %d, remains %d\n", + pr_debug("sllin: sllin_send_tx_buff sent %d, remains %d\n", sl->tx_cnt, remains); return 0; @@ -560,31 +658,37 @@ int sllin_send_break(struct sllin *sl) int sllin_send_break(struct sllin *sl) { struct tty_struct *tty = sl->tty; - unsigned long break_baud; - unsigned long flags; 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 + /* Do the break ourselves; Inspired by http://lxr.linux.no/#linux+v3.1.2/drivers/tty/tty_io.c#L2452 */ retval = tty->ops->break_ctl(tty, -1); if (retval) return retval; - //udelay(712); - usleep_range(650, 750); + /* 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(50, 100); - + 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; - printk(KERN_INFO "sllin: Break sent.\n"); + pr_debug("sllin: Break sent.\n"); set_bit(SLF_RXEVENT, &sl->flags); wake_up(&sl->kwt_wq); @@ -597,13 +701,47 @@ 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, SLLIN_ERR_RX_TIMEOUT); + sllin_report_error(sl, LIN_ERR_RX_TIMEOUT); set_bit(SLF_TMOUTEVENT, &sl->flags); wake_up(&sl->kwt_wq); return HRTIMER_NORESTART; } +/** + * sllin_rx_validate() -- Validate received frame, i,e. check checksum + * + * @sl: + */ +static int sllin_rx_validate(struct sllin *sl) +{ + int actual_id; + int ext_chcks_fl; + int lin_dlc; + unsigned char rec_chcksm = sl->rx_buff[sl->rx_cnt - 1]; + struct sllin_conf_entry *scf; + + actual_id = sl->rx_buff[SLLIN_BUFF_ID] & LIN_ID_MASK; + scf = &sl->linfr_cache[actual_id]; + lin_dlc = scf->dlc; + ext_chcks_fl = scf->frame_fl & LIN_CHECKSUM_EXTENDED; + + 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 @@ -614,20 +752,22 @@ int sllin_kwthread(void *ptr) struct sllin *sl = (struct sllin *)ptr; struct tty_struct *tty = sl->tty; struct sched_param schparam = { .sched_priority = 40 }; - int res; - struct can_frame *cf; - char *lin_data; - int lin_dlc; int tx_bytes = 0; /* Used for Network statistics */ - printk(KERN_INFO "sllin: sllin_kwthread started.\n"); + pr_debug("sllin: sllin_kwthread started.\n"); sched_setscheduler(current, SCHED_FIFO, &schparam); clear_bit(SLF_ERROR, &sl->flags); 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) { @@ -639,77 +779,102 @@ int sllin_kwthread(void *ptr) test_bit(SLF_RXEVENT, &sl->flags) || test_bit(SLF_TXEVENT, &sl->flags) || test_bit(SLF_TMOUTEVENT, &sl->flags) || - ((sl->lin_state == SLSTATE_IDLE) && test_bit(SLF_MSGEVENT, &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)) { - printk(KERN_INFO "sllin_kthread RXEVENT \n"); + 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)) { - printk(KERN_INFO "sllin_kthread TXEVENT \n"); + pr_debug("sllin: sllin_kthread TXEVENT\n"); } if (test_and_clear_bit(SLF_TMOUTEVENT, &sl->flags)) { - printk(KERN_INFO "sllin_kthread TMOUTEVENT \n"); - 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; - + pr_debug("sllin: sllin_kthread TMOUTEVENT\n"); + sllin_reset_buffs(sl); + sl->lin_state = SLSTATE_IDLE; } - if ((sl->lin_state == SLSTATE_IDLE) && test_bit(SLF_MSGEVENT, &sl->flags)) { - cf = (struct can_frame *)sl->rec_skb->data; - - /* EFF CAN frame -> "Configuration" frame */ - if (cf->can_id & CAN_EFF_FLAG) { - sllin_configure_frame_cache(sl, cf); - goto free_skb; - } /* SFF RTR CAN frame -> LIN header */ - else if (cf->can_id & CAN_RTR_FLAG) { - printk(KERN_INFO "%s: RTR SFF CAN frame, ID = %x\n", - __FUNCTION__, cf->can_id & SLLIN_ID_MASK); - - /* Is there Slave response in linfr_cache to be sent? */ - if ((sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].frame_fl & - SLLIN_LOC_SLAVE_CACHE) - && (sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].dlc > 0)) { - - printk(KERN_INFO "Sending LIN response from linfr_cache\n"); - lin_data = &sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].data; - lin_dlc = sl->linfr_cache[cf->can_id & SLLIN_ID_MASK].dlc; - } else { - lin_data = NULL; - lin_dlc = 0; + 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) { + spin_lock(&sl->lock); + pr_debug("sllin: %s: RTR SFF CAN frame, ID = %x\n", + __FUNCTION__, cf->can_id & LIN_ID_MASK); + + /* Is there Slave response in linfr_cache to be sent? */ + if ((sl->linfr_cache[cf->can_id & LIN_ID_MASK].frame_fl & + LIN_LOC_SLAVE_CACHE) + && (sl->linfr_cache[cf->can_id & LIN_ID_MASK].dlc > 0)) { + + pr_debug("sllin: Sending LIN response from linfr_cache\n"); + lin_data = sl->linfr_cache[cf->can_id & LIN_ID_MASK].data; + lin_dlc = sl->linfr_cache[cf->can_id & LIN_ID_MASK].dlc; + if (lin_dlc > SLLIN_DATA_MAX) + lin_dlc = SLLIN_DATA_MAX; + memcpy(lin_data_buff, lin_data, lin_dlc); + lin_data = lin_data_buff; + } else { + lin_data = NULL; + lin_dlc = sl->linfr_cache[cf->can_id & LIN_ID_MASK].dlc; + } + spin_unlock(&sl->lock); + } else { /* SFF NON-RTR CAN frame -> LIN header + LIN response */ + pr_debug("sllin: %s: NON-RTR SFF CAN frame, ID = %x\n", + __FUNCTION__, (int)cf->can_id & LIN_ID_MASK); + + lin_data = cf->data; + lin_dlc = cf->can_dlc; + if (lin_dlc > SLLIN_DATA_MAX) + lin_dlc = SLLIN_DATA_MAX; + tx_bytes = lin_dlc; } - } else { /* SFF NON-RTR CAN frame -> LIN header + LIN response */ - printk(KERN_INFO "%s: NON-RTR SFF CAN frame, ID = %x\n", - __FUNCTION__, (int)cf->can_id & SLLIN_ID_MASK); - - lin_data = cf->data; - lin_dlc = tx_bytes = cf->can_dlc; - } - if (sllin_setup_msg(sl, 0, cf->can_id & SLLIN_ID_MASK, - lin_data, lin_dlc) != -1) { + 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_dlc > 0) ? true : false; - sl->dev->stats.tx_packets++; - sl->dev->stats.tx_bytes += tx_bytes; - } + 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; + } - free_skb: - clear_bit(SLF_MSGEVENT, &sl->flags); - kfree_skb(sl->rec_skb); - netif_wake_queue(sl->dev); - } + 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; - switch (sl->lin_state) { case SLSTATE_BREAK_SENT: #ifdef BREAK_BY_BAUD if (sl->rx_cnt <= SLLIN_BUFF_BREAK) @@ -723,6 +888,7 @@ int sllin_kwthread(void *ptr) 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); @@ -730,10 +896,14 @@ int sllin_kwthread(void *ptr) sl->rx_expect = sl->tx_lim; goto slstate_response_sent; } else { - sl->rx_expect = SLLIN_BUFF_DATA + 2; + 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, + hrtimer_start(&sl->rx_timer, ktime_add(ktime_get(), sl->rx_timer_timeout), HRTIMER_MODE_ABS); goto slstate_response_wait; @@ -742,17 +912,59 @@ int sllin_kwthread(void *ptr) 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); - printk(KERN_INFO "sllin: response received ID %d len %d\n", + pr_debug("sllin: response received ID %d len %d\n", sl->rx_buff[SLLIN_BUFF_ID], sl->rx_cnt - SLLIN_BUFF_DATA - 1); - // FIXME: check checksum in sl->rx_buff - // send CAN non-RTR frame with data - printk(KERN_INFO "sllin: sending NON-RTR CAN frame with LIN payload."); - sll_bump(sl); //send packet to the network layer + 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; @@ -761,25 +973,20 @@ int sllin_kwthread(void *ptr) slstate_response_sent: if (sl->rx_cnt < sl->tx_lim) continue; - - sll_bump(sl); //send packet to the network layer - printk(KERN_INFO "sllin: response sent ID %d len %d\n", + + 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; } - - - - - /* sl->dev->stats.tx_packets++; send frames statistic */ - /* netif_wake_queue(sl->dev); allow next Tx packet arrival */ } hrtimer_cancel(&sl->rx_timer); - printk(KERN_INFO "sllin: sllin_kwthread stopped.\n"); + pr_debug("sllin: sllin_kwthread stopped.\n"); return 0; } @@ -911,27 +1118,19 @@ static int sllin_open(struct tty_struct *tty) /* Perform the low-level SLLIN initialization. */ sl->lin_master = true; - 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_reset_buffs(sl); sl->lin_baud = 19200; sl->lin_state = SLSTATE_IDLE; -#define SAMPLES_PER_CHAR 10 -#define CHARS_TO_TIMEOUT 12 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( - (1000000000 / sl->lin_baud) * - SAMPLES_PER_CHAR * CHARS_TO_TIMEOUT); - + (1000000000l / sl->lin_baud) * + SLLIN_SAMPLES_PER_CHAR * SLLIN_CHARS_TO_TIMEOUT); + set_bit(SLF_INUSE, &sl->flags); init_waitqueue_head(&sl->kwt_wq); @@ -946,7 +1145,7 @@ static int sllin_open(struct tty_struct *tty) /* Done. We have linked the TTY line to a channel. */ rtnl_unlock(); - tty->receive_room = SLLIN_BUFF_LEN * 40; /* 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; @@ -1046,7 +1245,7 @@ static int __init sllin_init(void) maxdev = 4; /* Sanity */ printk(banner); - printk(KERN_INFO "sllin: %d dynamic interface channels.\n", maxdev); + pr_debug("sllin: %d dynamic interface channels.\n", maxdev); sllin_devs = kzalloc(sizeof(struct net_device *)*maxdev, GFP_KERNEL); if (!sllin_devs) { @@ -1060,6 +1259,13 @@ static int __init sllin_init(void) printk(KERN_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; }