diff options
Diffstat (limited to 'drivers/net/can/usb/kvaser_usb.c')
| -rw-r--r-- | drivers/net/can/usb/kvaser_usb.c | 176 |
1 files changed, 112 insertions, 64 deletions
diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c index 2928f7003041..57611fd91229 100644 --- a/drivers/net/can/usb/kvaser_usb.c +++ b/drivers/net/can/usb/kvaser_usb.c @@ -14,6 +14,8 @@ * Copyright (C) 2015 Valeo S.A. */ +#include <linux/spinlock.h> +#include <linux/kernel.h> #include <linux/completion.h> #include <linux/module.h> #include <linux/netdevice.h> @@ -23,7 +25,6 @@ #include <linux/can/dev.h> #include <linux/can/error.h> -#define MAX_TX_URBS 16 #define MAX_RX_URBS 4 #define START_TIMEOUT 1000 /* msecs */ #define STOP_TIMEOUT 1000 /* msecs */ @@ -441,6 +442,7 @@ struct kvaser_usb_error_summary { }; }; +/* Context for an outstanding, not yet ACKed, transmission */ struct kvaser_usb_tx_urb_context { struct kvaser_usb_net_priv *priv; u32 echo_index; @@ -454,8 +456,13 @@ struct kvaser_usb { struct usb_endpoint_descriptor *bulk_in, *bulk_out; struct usb_anchor rx_submitted; + /* @max_tx_urbs: Firmware-reported maximum number of oustanding, + * not yet ACKed, transmissions on this device. This value is + * also used as a sentinel for marking free tx contexts. + */ u32 fw_version; unsigned int nchannels; + unsigned int max_tx_urbs; enum kvaser_usb_family family; bool rxinitdone; @@ -465,18 +472,18 @@ struct kvaser_usb { struct kvaser_usb_net_priv { struct can_priv can; - - atomic_t active_tx_urbs; - struct usb_anchor tx_submitted; - struct kvaser_usb_tx_urb_context tx_contexts[MAX_TX_URBS]; - - struct completion start_comp, stop_comp; + struct can_berr_counter bec; struct kvaser_usb *dev; struct net_device *netdev; int channel; - struct can_berr_counter bec; + struct completion start_comp, stop_comp; + struct usb_anchor tx_submitted; + + spinlock_t tx_contexts_lock; + int active_tx_contexts; + struct kvaser_usb_tx_urb_context tx_contexts[]; }; static const struct usb_device_id kvaser_usb_table[] = { @@ -584,8 +591,15 @@ static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id, while (pos <= actual_len - MSG_HEADER_LEN) { tmp = buf + pos; - if (!tmp->len) - break; + /* Handle messages crossing the USB endpoint max packet + * size boundary. Check kvaser_usb_read_bulk_callback() + * for further details. + */ + if (tmp->len == 0) { + pos = round_up(pos, le16_to_cpu(dev->bulk_in-> + wMaxPacketSize)); + continue; + } if (pos + tmp->len > actual_len) { dev_err(dev->udev->dev.parent, @@ -647,9 +661,13 @@ static int kvaser_usb_get_software_info(struct kvaser_usb *dev) switch (dev->family) { case KVASER_LEAF: dev->fw_version = le32_to_cpu(msg.u.leaf.softinfo.fw_version); + dev->max_tx_urbs = + le16_to_cpu(msg.u.leaf.softinfo.max_outstanding_tx); break; case KVASER_USBCAN: dev->fw_version = le32_to_cpu(msg.u.usbcan.softinfo.fw_version); + dev->max_tx_urbs = + le16_to_cpu(msg.u.usbcan.softinfo.max_outstanding_tx); break; } @@ -686,6 +704,7 @@ static void kvaser_usb_tx_acknowledge(const struct kvaser_usb *dev, struct kvaser_usb_net_priv *priv; struct sk_buff *skb; struct can_frame *cf; + unsigned long flags; u8 channel, tid; channel = msg->u.tx_acknowledge_header.channel; @@ -704,7 +723,7 @@ static void kvaser_usb_tx_acknowledge(const struct kvaser_usb *dev, stats = &priv->netdev->stats; - context = &priv->tx_contexts[tid % MAX_TX_URBS]; + context = &priv->tx_contexts[tid % dev->max_tx_urbs]; /* Sometimes the state change doesn't come after a bus-off event */ if (priv->can.restart_ms && @@ -729,12 +748,15 @@ static void kvaser_usb_tx_acknowledge(const struct kvaser_usb *dev, stats->tx_packets++; stats->tx_bytes += context->dlc; - can_get_echo_skb(priv->netdev, context->echo_index); - context->echo_index = MAX_TX_URBS; - atomic_dec(&priv->active_tx_urbs); + spin_lock_irqsave(&priv->tx_contexts_lock, flags); + can_get_echo_skb(priv->netdev, context->echo_index); + context->echo_index = dev->max_tx_urbs; + --priv->active_tx_contexts; netif_wake_queue(priv->netdev); + + spin_unlock_irqrestore(&priv->tx_contexts_lock, flags); } static void kvaser_usb_simple_msg_callback(struct urb *urb) @@ -787,7 +809,6 @@ static int kvaser_usb_simple_msg_async(struct kvaser_usb_net_priv *priv, netdev_err(netdev, "Error transmitting URB\n"); usb_unanchor_urb(urb); usb_free_urb(urb); - kfree(buf); return err; } @@ -796,17 +817,6 @@ static int kvaser_usb_simple_msg_async(struct kvaser_usb_net_priv *priv, return 0; } -static void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv) -{ - int i; - - usb_kill_anchored_urbs(&priv->tx_submitted); - atomic_set(&priv->active_tx_urbs, 0); - - for (i = 0; i < MAX_TX_URBS; i++) - priv->tx_contexts[i].echo_index = MAX_TX_URBS; -} - static void kvaser_usb_rx_error_update_can_state(struct kvaser_usb_net_priv *priv, const struct kvaser_usb_error_summary *es, struct can_frame *cf) @@ -1317,8 +1327,20 @@ static void kvaser_usb_read_bulk_callback(struct urb *urb) while (pos <= urb->actual_length - MSG_HEADER_LEN) { msg = urb->transfer_buffer + pos; - if (!msg->len) - break; + /* The Kvaser firmware can only read and write messages that + * does not cross the USB's endpoint wMaxPacketSize boundary. + * If a follow-up command crosses such boundary, firmware puts + * a placeholder zero-length command in its place then aligns + * the real command to the next max packet size. + * + * Handle such cases or we're going to miss a significant + * number of events in case of a heavy rx load on the bus. + */ + if (msg->len == 0) { + pos = round_up(pos, le16_to_cpu(dev->bulk_in-> + wMaxPacketSize)); + continue; + } if (pos + msg->len > urb->actual_length) { dev_err(dev->udev->dev.parent, "Format error\n"); @@ -1326,7 +1348,6 @@ static void kvaser_usb_read_bulk_callback(struct urb *urb) } kvaser_usb_handle_message(dev, msg); - pos += msg->len; } @@ -1498,6 +1519,26 @@ error: return err; } +static void kvaser_usb_reset_tx_urb_contexts(struct kvaser_usb_net_priv *priv) +{ + int i, max_tx_urbs; + + max_tx_urbs = priv->dev->max_tx_urbs; + + priv->active_tx_contexts = 0; + for (i = 0; i < max_tx_urbs; i++) + priv->tx_contexts[i].echo_index = max_tx_urbs; +} + +/* This method might sleep. Do not call it in the atomic context + * of URB completions. + */ +static void kvaser_usb_unlink_tx_urbs(struct kvaser_usb_net_priv *priv) +{ + usb_kill_anchored_urbs(&priv->tx_submitted); + kvaser_usb_reset_tx_urb_contexts(priv); +} + static void kvaser_usb_unlink_all_urbs(struct kvaser_usb *dev) { int i; @@ -1615,9 +1656,9 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb, struct urb *urb; void *buf; struct kvaser_msg *msg; - int i, err; - int ret = NETDEV_TX_OK; + int i, err, ret = NETDEV_TX_OK; u8 *msg_tx_can_flags = NULL; /* GCC */ + unsigned long flags; if (can_dropped_invalid_skb(netdev, skb)) return NETDEV_TX_OK; @@ -1634,7 +1675,7 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb, if (!buf) { stats->tx_dropped++; dev_kfree_skb(skb); - goto nobufmem; + goto freeurb; } msg = buf; @@ -1671,22 +1712,32 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb, if (cf->can_id & CAN_RTR_FLAG) *msg_tx_can_flags |= MSG_FLAG_REMOTE_FRAME; - for (i = 0; i < ARRAY_SIZE(priv->tx_contexts); i++) { - if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) { + spin_lock_irqsave(&priv->tx_contexts_lock, flags); + for (i = 0; i < dev->max_tx_urbs; i++) { + if (priv->tx_contexts[i].echo_index == dev->max_tx_urbs) { context = &priv->tx_contexts[i]; + + context->echo_index = i; + can_put_echo_skb(skb, netdev, context->echo_index); + ++priv->active_tx_contexts; + if (priv->active_tx_contexts >= dev->max_tx_urbs) + netif_stop_queue(netdev); + break; } } + spin_unlock_irqrestore(&priv->tx_contexts_lock, flags); /* This should never happen; it implies a flow control bug */ if (!context) { netdev_warn(netdev, "cannot find free context\n"); + + kfree(buf); ret = NETDEV_TX_BUSY; - goto releasebuf; + goto freeurb; } context->priv = priv; - context->echo_index = i; context->dlc = cf->can_dlc; msg->u.tx_can.tid = context->echo_index; @@ -1698,18 +1749,17 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb, kvaser_usb_write_bulk_callback, context); usb_anchor_urb(urb, &priv->tx_submitted); - can_put_echo_skb(skb, netdev, context->echo_index); - - atomic_inc(&priv->active_tx_urbs); - - if (atomic_read(&priv->active_tx_urbs) >= MAX_TX_URBS) - netif_stop_queue(netdev); - err = usb_submit_urb(urb, GFP_ATOMIC); if (unlikely(err)) { + spin_lock_irqsave(&priv->tx_contexts_lock, flags); + can_free_echo_skb(netdev, context->echo_index); + context->echo_index = dev->max_tx_urbs; + --priv->active_tx_contexts; + netif_wake_queue(netdev); + + spin_unlock_irqrestore(&priv->tx_contexts_lock, flags); - atomic_dec(&priv->active_tx_urbs); usb_unanchor_urb(urb); stats->tx_dropped++; @@ -1719,16 +1769,12 @@ static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb, else netdev_warn(netdev, "Failed tx_urb %d\n", err); - goto releasebuf; + goto freeurb; } - usb_free_urb(urb); - - return NETDEV_TX_OK; + ret = NETDEV_TX_OK; -releasebuf: - kfree(buf); -nobufmem: +freeurb: usb_free_urb(urb); return ret; } @@ -1840,13 +1886,15 @@ static int kvaser_usb_init_one(struct usb_interface *intf, struct kvaser_usb *dev = usb_get_intfdata(intf); struct net_device *netdev; struct kvaser_usb_net_priv *priv; - int i, err; + int err; err = kvaser_usb_send_simple_msg(dev, CMD_RESET_CHIP, channel); if (err) return err; - netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS); + netdev = alloc_candev(sizeof(*priv) + + dev->max_tx_urbs * sizeof(*priv->tx_contexts), + dev->max_tx_urbs); if (!netdev) { dev_err(&intf->dev, "Cannot alloc candev\n"); return -ENOMEM; @@ -1854,19 +1902,17 @@ static int kvaser_usb_init_one(struct usb_interface *intf, priv = netdev_priv(netdev); + init_usb_anchor(&priv->tx_submitted); init_completion(&priv->start_comp); init_completion(&priv->stop_comp); - init_usb_anchor(&priv->tx_submitted); - atomic_set(&priv->active_tx_urbs, 0); - - for (i = 0; i < ARRAY_SIZE(priv->tx_contexts); i++) - priv->tx_contexts[i].echo_index = MAX_TX_URBS; - priv->dev = dev; priv->netdev = netdev; priv->channel = channel; + spin_lock_init(&priv->tx_contexts_lock); + kvaser_usb_reset_tx_urb_contexts(priv); + priv->can.state = CAN_STATE_STOPPED; priv->can.clock.freq = CAN_USB_CLOCK; priv->can.bittiming_const = &kvaser_usb_bittiming_const; @@ -1976,6 +2022,13 @@ static int kvaser_usb_probe(struct usb_interface *intf, return err; } + dev_dbg(&intf->dev, "Firmware version: %d.%d.%d\n", + ((dev->fw_version >> 24) & 0xff), + ((dev->fw_version >> 16) & 0xff), + (dev->fw_version & 0xffff)); + + dev_dbg(&intf->dev, "Max oustanding tx = %d URBs\n", dev->max_tx_urbs); + err = kvaser_usb_get_card_info(dev); if (err) { dev_err(&intf->dev, @@ -1983,11 +2036,6 @@ static int kvaser_usb_probe(struct usb_interface *intf, return err; } - dev_dbg(&intf->dev, "Firmware version: %d.%d.%d\n", - ((dev->fw_version >> 24) & 0xff), - ((dev->fw_version >> 16) & 0xff), - (dev->fw_version & 0xffff)); - for (i = 0; i < dev->nchannels; i++) { err = kvaser_usb_init_one(intf, id, i); if (err) { |