--- zzzz-none-000/linux-3.10.107/drivers/net/can/slcan.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/net/can/slcan.c 2021-02-04 17:41:59.000000000 +0000 @@ -18,9 +18,7 @@ * General Public License for more details. * * You should have received a copy of the GNU General Public License along - * with this program; if not, write to the Free Software Foundation, Inc., - * 59 Temple Place, Suite 330, Boston, MA 02111-1307. You can also get it - * at http://www.gnu.org/licenses/gpl.html + * with this program; if not, see http://www.gnu.org/licenses/gpl.html * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT @@ -54,12 +52,10 @@ #include #include #include +#include #include #include -static __initconst const char banner[] = - KERN_INFO "slcan: serial line CAN interface driver\n"; - MODULE_ALIAS_LDISC(N_SLCAN); MODULE_DESCRIPTION("serial line CAN interface"); MODULE_LICENSE("GPL"); @@ -76,6 +72,10 @@ /* maximum rx buffer len: extended CAN frame with timestamp */ #define SLC_MTU (sizeof("T1111222281122334455667788EA5F\r")+1) +#define SLC_CMD_LEN 1 +#define SLC_SFF_ID_LEN 3 +#define SLC_EFF_ID_LEN 8 + struct slcan { int magic; @@ -83,6 +83,7 @@ struct tty_struct *tty; /* ptr to TTY structure */ struct net_device *dev; /* easy for intr handling */ spinlock_t lock; + struct work_struct tx_work; /* Flushes transmit buffer */ /* These are pointers to the malloc()ed frame buffers. */ unsigned char rbuff[SLC_MTU]; /* receiver buffer */ @@ -142,47 +143,63 @@ { 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')) + int i, tmp; + u32 tmpid; + char *cmd = sl->rbuff; + + cf.can_id = 0; + + switch (*cmd) { + case 'r': + cf.can_id = CAN_RTR_FLAG; + /* fallthrough */ + case 't': + /* store dlc ASCII value and terminate SFF CAN ID string */ + cf.can_dlc = sl->rbuff[SLC_CMD_LEN + SLC_SFF_ID_LEN]; + sl->rbuff[SLC_CMD_LEN + SLC_SFF_ID_LEN] = 0; + /* point to payload data behind the dlc */ + cmd += SLC_CMD_LEN + SLC_SFF_ID_LEN + 1; + break; + case 'R': + cf.can_id = CAN_RTR_FLAG; + /* fallthrough */ + case 'T': + cf.can_id |= CAN_EFF_FLAG; + /* store dlc ASCII value and terminate EFF CAN ID string */ + cf.can_dlc = sl->rbuff[SLC_CMD_LEN + SLC_EFF_ID_LEN]; + sl->rbuff[SLC_CMD_LEN + SLC_EFF_ID_LEN] = 0; + /* point to payload data behind the dlc */ + cmd += SLC_CMD_LEN + SLC_EFF_ID_LEN + 1; + break; + default: 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'))) + if (kstrtou32(sl->rbuff + SLC_CMD_LEN, 16, &tmpid)) return; - cf.can_dlc = sl->rbuff[dlc_pos] - '0'; /* get can_dlc from ASCII val */ - - sl->rbuff[dlc_pos] = 0; /* terminate can_id string */ + cf.can_id |= tmpid; - if (strict_strtoul(sl->rbuff+1, 16, &ultmp)) + /* get can_dlc from sanitized ASCII value */ + if (cf.can_dlc >= '0' && cf.can_dlc < '9') + cf.can_dlc -= '0'; + else 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 = hex_to_bin(sl->rbuff[dlc_pos++]); - if (tmp < 0) - return; - cf.data[i] = (tmp << 4); - tmp = hex_to_bin(sl->rbuff[dlc_pos++]); - if (tmp < 0) - return; - cf.data[i] |= tmp; + /* RTR frames may have a dlc > 0 but they never have any data bytes */ + if (!(cf.can_id & CAN_RTR_FLAG)) { + for (i = 0; i < cf.can_dlc; i++) { + tmp = hex_to_bin(*cmd++); + if (tmp < 0) + return; + cf.data[i] = (tmp << 4); + tmp = hex_to_bin(*cmd++); + if (tmp < 0) + return; + cf.data[i] |= tmp; + } } skb = dev_alloc_skb(sizeof(struct can_frame) + @@ -197,19 +214,19 @@ can_skb_reserve(skb); can_skb_prv(skb)->ifindex = sl->dev->ifindex; + can_skb_prv(skb)->skbcnt = 0; memcpy(skb_put(skb, sizeof(struct can_frame)), &cf, sizeof(struct can_frame)); - netif_rx_ni(skb); sl->dev->stats.rx_packets++; sl->dev->stats.rx_bytes += cf.can_dlc; + netif_rx_ni(skb); } /* parse tty input stream */ static void slcan_unesc(struct slcan *sl, unsigned char s) { - if ((s == '\r') || (s == '\a')) { /* CR or BEL ends the pdu */ if (!test_and_clear_bit(SLF_ERROR, &sl->flags) && (sl->rcount > 4)) { @@ -236,27 +253,46 @@ /* Encapsulate one can_frame and stuff into a TTY queue. */ static void slc_encaps(struct slcan *sl, struct can_frame *cf) { - int actual, idx, i; - char cmd; + int actual, i; + unsigned char *pos; + unsigned char *endpos; + canid_t id = cf->can_id; + + pos = sl->xbuff; if (cf->can_id & CAN_RTR_FLAG) - cmd = 'R'; /* becomes 'r' in standard frame format */ + *pos = 'R'; /* becomes 'r' in standard frame format (SFF) */ else - cmd = 'T'; /* becomes 't' in standard frame format */ + *pos = 'T'; /* becomes 't' in standard frame format (SSF) */ - 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); + /* determine number of chars for the CAN-identifier */ + if (cf->can_id & CAN_EFF_FLAG) { + id &= CAN_EFF_MASK; + endpos = pos + SLC_EFF_ID_LEN; + } else { + *pos |= 0x20; /* convert R/T to lower case for SFF */ + id &= CAN_SFF_MASK; + endpos = pos + SLC_SFF_ID_LEN; + } + + /* build 3 (SFF) or 8 (EFF) digit CAN identifier */ + pos++; + while (endpos >= pos) { + *endpos-- = hex_asc_upper[id & 0xf]; + id >>= 4; + } + + pos += (cf->can_id & CAN_EFF_FLAG) ? SLC_EFF_ID_LEN : SLC_SFF_ID_LEN; - idx = strlen(sl->xbuff); + *pos++ = cf->can_dlc + '0'; - for (i = 0; i < cf->can_dlc; i++) - sprintf(&sl->xbuff[idx + 2*i], "%02X", cf->data[i]); + /* RTR frames may have a dlc > 0 but they never have any data bytes */ + if (!(cf->can_id & CAN_RTR_FLAG)) { + for (i = 0; i < cf->can_dlc; i++) + pos = hex_byte_pack_upper(pos, cf->data[i]); + } - strcat(sl->xbuff, "\r"); /* add terminating character */ + *pos++ = '\r'; /* Order of next two lines is *very* important. * When we are sending a little amount of data, @@ -267,37 +303,50 @@ * 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; + actual = sl->tty->ops->write(sl->tty, sl->xbuff, pos - sl->xbuff); + sl->xleft = (pos - sl->xbuff) - actual; sl->xhead = sl->xbuff + actual; sl->dev->stats.tx_bytes += cf->can_dlc; } -/* - * 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) +/* Write out any remaining transmit buffer. Scheduled when tty is writable */ +static void slcan_transmit(struct work_struct *work) { + struct slcan *sl = container_of(work, struct slcan, tx_work); int actual; - struct slcan *sl = (struct slcan *) tty->disc_data; + spin_lock_bh(&sl->lock); /* First make sure we're connected. */ - if (!sl || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev)) + if (!sl->tty || sl->magic != SLCAN_MAGIC || !netif_running(sl->dev)) { + spin_unlock_bh(&sl->lock); 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); + clear_bit(TTY_DO_WRITE_WAKEUP, &sl->tty->flags); + spin_unlock_bh(&sl->lock); netif_wake_queue(sl->dev); return; } - actual = tty->ops->write(tty, sl->xhead, sl->xleft); + actual = sl->tty->ops->write(sl->tty, sl->xhead, sl->xleft); sl->xleft -= actual; sl->xhead += actual; + spin_unlock_bh(&sl->lock); +} + +/* + * Called by the driver when there's room for more data. + * Schedule the transmit. + */ +static void slcan_write_wakeup(struct tty_struct *tty) +{ + struct slcan *sl = tty->disc_data; + + schedule_work(&sl->tx_work); } /* Send a can_frame to a TTY queue. */ @@ -372,10 +421,16 @@ slcan_devs[i] = NULL; } +static int slcan_change_mtu(struct net_device *dev, int new_mtu) +{ + return -EINVAL; +} + static const struct net_device_ops slc_netdev_ops = { .ndo_open = slc_open, .ndo_stop = slc_close, .ndo_start_xmit = slc_xmit, + .ndo_change_mtu = slcan_change_mtu, }; static void slc_setup(struct net_device *dev) @@ -472,7 +527,7 @@ return NULL; sprintf(name, "slcan%d", i); - dev = alloc_netdev(sizeof(*sl), name, slc_setup); + dev = alloc_netdev(sizeof(*sl), name, NET_NAME_UNKNOWN, slc_setup); if (!dev) return NULL; @@ -483,6 +538,7 @@ sl->magic = SLCAN_MAGIC; sl->dev = dev; spin_lock_init(&sl->lock); + INIT_WORK(&sl->tx_work, slcan_transmit); slcan_devs[i] = dev; return sl; @@ -581,8 +637,12 @@ if (!sl || sl->magic != SLCAN_MAGIC || sl->tty != tty) return; + spin_lock_bh(&sl->lock); tty->disc_data = NULL; sl->tty = NULL; + spin_unlock_bh(&sl->lock); + + flush_work(&sl->tx_work); /* Flush network side */ unregister_netdev(sl->dev); @@ -640,8 +700,8 @@ if (maxdev < 4) maxdev = 4; /* Sanity */ - printk(banner); - printk(KERN_INFO "slcan: %d dynamic interface channels.\n", maxdev); + pr_info("slcan: serial line CAN interface driver\n"); + pr_info("slcan: %d dynamic interface channels.\n", maxdev); slcan_devs = kzalloc(sizeof(struct net_device *)*maxdev, GFP_KERNEL); if (!slcan_devs)