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path: root/drivers/net/can/usb/esd_usb.c
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-rw-r--r--drivers/net/can/usb/esd_usb.c1153
1 files changed, 1153 insertions, 0 deletions
diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
new file mode 100644
index 000000000000..81b88e9e5bdc
--- /dev/null
+++ b/drivers/net/can/usb/esd_usb.c
@@ -0,0 +1,1153 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * CAN driver for esd electronics gmbh CAN-USB/2 and CAN-USB/Micro
+ *
+ * Copyright (C) 2010-2012 esd electronic system design gmbh, Matthias Fuchs <socketcan@esd.eu>
+ * Copyright (C) 2022 esd electronics gmbh, Frank Jungclaus <frank.jungclaus@esd.eu>
+ */
+#include <linux/ethtool.h>
+#include <linux/signal.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/usb.h>
+
+#include <linux/can.h>
+#include <linux/can/dev.h>
+#include <linux/can/error.h>
+
+MODULE_AUTHOR("Matthias Fuchs <socketcan@esd.eu>");
+MODULE_AUTHOR("Frank Jungclaus <frank.jungclaus@esd.eu>");
+MODULE_DESCRIPTION("CAN driver for esd electronics gmbh CAN-USB/2 and CAN-USB/Micro interfaces");
+MODULE_LICENSE("GPL v2");
+
+/* USB vendor and product ID */
+#define USB_ESDGMBH_VENDOR_ID 0x0ab4
+#define USB_CANUSB2_PRODUCT_ID 0x0010
+#define USB_CANUSBM_PRODUCT_ID 0x0011
+
+/* CAN controller clock frequencies */
+#define ESD_USB2_CAN_CLOCK 60000000
+#define ESD_USBM_CAN_CLOCK 36000000
+
+/* Maximum number of CAN nets */
+#define ESD_USB_MAX_NETS 2
+
+/* USB commands */
+#define CMD_VERSION 1 /* also used for VERSION_REPLY */
+#define CMD_CAN_RX 2 /* device to host only */
+#define CMD_CAN_TX 3 /* also used for TX_DONE */
+#define CMD_SETBAUD 4 /* also used for SETBAUD_REPLY */
+#define CMD_TS 5 /* also used for TS_REPLY */
+#define CMD_IDADD 6 /* also used for IDADD_REPLY */
+
+/* esd CAN message flags - dlc field */
+#define ESD_RTR 0x10
+
+/* esd CAN message flags - id field */
+#define ESD_EXTID 0x20000000
+#define ESD_EVENT 0x40000000
+#define ESD_IDMASK 0x1fffffff
+
+/* esd CAN event ids */
+#define ESD_EV_CAN_ERROR_EXT 2 /* CAN controller specific diagnostic data */
+
+/* baudrate message flags */
+#define ESD_USB_UBR 0x80000000
+#define ESD_USB_LOM 0x40000000
+#define ESD_USB_NO_BAUDRATE 0x7fffffff
+
+/* bit timing CAN-USB/2 */
+#define ESD_USB2_TSEG1_MIN 1
+#define ESD_USB2_TSEG1_MAX 16
+#define ESD_USB2_TSEG1_SHIFT 16
+#define ESD_USB2_TSEG2_MIN 1
+#define ESD_USB2_TSEG2_MAX 8
+#define ESD_USB2_TSEG2_SHIFT 20
+#define ESD_USB2_SJW_MAX 4
+#define ESD_USB2_SJW_SHIFT 14
+#define ESD_USBM_SJW_SHIFT 24
+#define ESD_USB2_BRP_MIN 1
+#define ESD_USB2_BRP_MAX 1024
+#define ESD_USB2_BRP_INC 1
+#define ESD_USB2_3_SAMPLES 0x00800000
+
+/* esd IDADD message */
+#define ESD_ID_ENABLE 0x80
+#define ESD_MAX_ID_SEGMENT 64
+
+/* SJA1000 ECC register (emulated by usb firmware) */
+#define SJA1000_ECC_SEG 0x1F
+#define SJA1000_ECC_DIR 0x20
+#define SJA1000_ECC_ERR 0x06
+#define SJA1000_ECC_BIT 0x00
+#define SJA1000_ECC_FORM 0x40
+#define SJA1000_ECC_STUFF 0x80
+#define SJA1000_ECC_MASK 0xc0
+
+/* esd bus state event codes */
+#define ESD_BUSSTATE_MASK 0xc0
+#define ESD_BUSSTATE_WARN 0x40
+#define ESD_BUSSTATE_ERRPASSIVE 0x80
+#define ESD_BUSSTATE_BUSOFF 0xc0
+
+#define RX_BUFFER_SIZE 1024
+#define MAX_RX_URBS 4
+#define MAX_TX_URBS 16 /* must be power of 2 */
+
+struct header_msg {
+ u8 len; /* len is always the total message length in 32bit words */
+ u8 cmd;
+ u8 rsvd[2];
+};
+
+struct version_msg {
+ u8 len;
+ u8 cmd;
+ u8 rsvd;
+ u8 flags;
+ __le32 drv_version;
+};
+
+struct version_reply_msg {
+ u8 len;
+ u8 cmd;
+ u8 nets;
+ u8 features;
+ __le32 version;
+ u8 name[16];
+ __le32 rsvd;
+ __le32 ts;
+};
+
+struct rx_msg {
+ u8 len;
+ u8 cmd;
+ u8 net;
+ u8 dlc;
+ __le32 ts;
+ __le32 id; /* upper 3 bits contain flags */
+ u8 data[8];
+};
+
+struct tx_msg {
+ u8 len;
+ u8 cmd;
+ u8 net;
+ u8 dlc;
+ u32 hnd; /* opaque handle, not used by device */
+ __le32 id; /* upper 3 bits contain flags */
+ u8 data[8];
+};
+
+struct tx_done_msg {
+ u8 len;
+ u8 cmd;
+ u8 net;
+ u8 status;
+ u32 hnd; /* opaque handle, not used by device */
+ __le32 ts;
+};
+
+struct id_filter_msg {
+ u8 len;
+ u8 cmd;
+ u8 net;
+ u8 option;
+ __le32 mask[ESD_MAX_ID_SEGMENT + 1];
+};
+
+struct set_baudrate_msg {
+ u8 len;
+ u8 cmd;
+ u8 net;
+ u8 rsvd;
+ __le32 baud;
+};
+
+/* Main message type used between library and application */
+struct __packed esd_usb_msg {
+ union {
+ struct header_msg hdr;
+ struct version_msg version;
+ struct version_reply_msg version_reply;
+ struct rx_msg rx;
+ struct tx_msg tx;
+ struct tx_done_msg txdone;
+ struct set_baudrate_msg setbaud;
+ struct id_filter_msg filter;
+ } msg;
+};
+
+static struct usb_device_id esd_usb_table[] = {
+ {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSB2_PRODUCT_ID)},
+ {USB_DEVICE(USB_ESDGMBH_VENDOR_ID, USB_CANUSBM_PRODUCT_ID)},
+ {}
+};
+MODULE_DEVICE_TABLE(usb, esd_usb_table);
+
+struct esd_usb_net_priv;
+
+struct esd_tx_urb_context {
+ struct esd_usb_net_priv *priv;
+ u32 echo_index;
+};
+
+struct esd_usb {
+ struct usb_device *udev;
+ struct esd_usb_net_priv *nets[ESD_USB_MAX_NETS];
+
+ struct usb_anchor rx_submitted;
+
+ int net_count;
+ u32 version;
+ int rxinitdone;
+ void *rxbuf[MAX_RX_URBS];
+ dma_addr_t rxbuf_dma[MAX_RX_URBS];
+};
+
+struct esd_usb_net_priv {
+ struct can_priv can; /* must be the first member */
+
+ atomic_t active_tx_jobs;
+ struct usb_anchor tx_submitted;
+ struct esd_tx_urb_context tx_contexts[MAX_TX_URBS];
+
+ struct esd_usb *usb;
+ struct net_device *netdev;
+ int index;
+ u8 old_state;
+ struct can_berr_counter bec;
+};
+
+static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
+ struct esd_usb_msg *msg)
+{
+ struct net_device_stats *stats = &priv->netdev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ u32 id = le32_to_cpu(msg->msg.rx.id) & ESD_IDMASK;
+
+ if (id == ESD_EV_CAN_ERROR_EXT) {
+ u8 state = msg->msg.rx.data[0];
+ u8 ecc = msg->msg.rx.data[1];
+ u8 rxerr = msg->msg.rx.data[2];
+ u8 txerr = msg->msg.rx.data[3];
+
+ skb = alloc_can_err_skb(priv->netdev, &cf);
+ if (skb == NULL) {
+ stats->rx_dropped++;
+ return;
+ }
+
+ if (state != priv->old_state) {
+ priv->old_state = state;
+
+ switch (state & ESD_BUSSTATE_MASK) {
+ case ESD_BUSSTATE_BUSOFF:
+ priv->can.state = CAN_STATE_BUS_OFF;
+ cf->can_id |= CAN_ERR_BUSOFF;
+ priv->can.can_stats.bus_off++;
+ can_bus_off(priv->netdev);
+ break;
+ case ESD_BUSSTATE_WARN:
+ priv->can.state = CAN_STATE_ERROR_WARNING;
+ priv->can.can_stats.error_warning++;
+ break;
+ case ESD_BUSSTATE_ERRPASSIVE:
+ priv->can.state = CAN_STATE_ERROR_PASSIVE;
+ priv->can.can_stats.error_passive++;
+ break;
+ default:
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+ break;
+ }
+ } else {
+ priv->can.can_stats.bus_error++;
+ stats->rx_errors++;
+
+ cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR |
+ CAN_ERR_CNT;
+
+ switch (ecc & SJA1000_ECC_MASK) {
+ case SJA1000_ECC_BIT:
+ cf->data[2] |= CAN_ERR_PROT_BIT;
+ break;
+ case SJA1000_ECC_FORM:
+ cf->data[2] |= CAN_ERR_PROT_FORM;
+ break;
+ case SJA1000_ECC_STUFF:
+ cf->data[2] |= CAN_ERR_PROT_STUFF;
+ break;
+ default:
+ cf->data[3] = ecc & SJA1000_ECC_SEG;
+ break;
+ }
+
+ /* Error occurred during transmission? */
+ if (!(ecc & SJA1000_ECC_DIR))
+ cf->data[2] |= CAN_ERR_PROT_TX;
+
+ if (priv->can.state == CAN_STATE_ERROR_WARNING ||
+ priv->can.state == CAN_STATE_ERROR_PASSIVE) {
+ cf->data[1] = (txerr > rxerr) ?
+ CAN_ERR_CRTL_TX_PASSIVE :
+ CAN_ERR_CRTL_RX_PASSIVE;
+ }
+ cf->data[6] = txerr;
+ cf->data[7] = rxerr;
+ }
+
+ priv->bec.txerr = txerr;
+ priv->bec.rxerr = rxerr;
+
+ netif_rx(skb);
+ }
+}
+
+static void esd_usb_rx_can_msg(struct esd_usb_net_priv *priv,
+ struct esd_usb_msg *msg)
+{
+ struct net_device_stats *stats = &priv->netdev->stats;
+ struct can_frame *cf;
+ struct sk_buff *skb;
+ int i;
+ u32 id;
+
+ if (!netif_device_present(priv->netdev))
+ return;
+
+ id = le32_to_cpu(msg->msg.rx.id);
+
+ if (id & ESD_EVENT) {
+ esd_usb_rx_event(priv, msg);
+ } else {
+ skb = alloc_can_skb(priv->netdev, &cf);
+ if (skb == NULL) {
+ stats->rx_dropped++;
+ return;
+ }
+
+ cf->can_id = id & ESD_IDMASK;
+ can_frame_set_cc_len(cf, msg->msg.rx.dlc & ~ESD_RTR,
+ priv->can.ctrlmode);
+
+ if (id & ESD_EXTID)
+ cf->can_id |= CAN_EFF_FLAG;
+
+ if (msg->msg.rx.dlc & ESD_RTR) {
+ cf->can_id |= CAN_RTR_FLAG;
+ } else {
+ for (i = 0; i < cf->len; i++)
+ cf->data[i] = msg->msg.rx.data[i];
+
+ stats->rx_bytes += cf->len;
+ }
+ stats->rx_packets++;
+
+ netif_rx(skb);
+ }
+}
+
+static void esd_usb_tx_done_msg(struct esd_usb_net_priv *priv,
+ struct esd_usb_msg *msg)
+{
+ struct net_device_stats *stats = &priv->netdev->stats;
+ struct net_device *netdev = priv->netdev;
+ struct esd_tx_urb_context *context;
+
+ if (!netif_device_present(netdev))
+ return;
+
+ context = &priv->tx_contexts[msg->msg.txdone.hnd & (MAX_TX_URBS - 1)];
+
+ if (!msg->msg.txdone.status) {
+ stats->tx_packets++;
+ stats->tx_bytes += can_get_echo_skb(netdev, context->echo_index,
+ NULL);
+ } else {
+ stats->tx_errors++;
+ can_free_echo_skb(netdev, context->echo_index, NULL);
+ }
+
+ /* Release context */
+ context->echo_index = MAX_TX_URBS;
+ atomic_dec(&priv->active_tx_jobs);
+
+ netif_wake_queue(netdev);
+}
+
+static void esd_usb_read_bulk_callback(struct urb *urb)
+{
+ struct esd_usb *dev = urb->context;
+ int retval;
+ int pos = 0;
+ int i;
+
+ switch (urb->status) {
+ case 0: /* success */
+ break;
+
+ case -ENOENT:
+ case -EPIPE:
+ case -EPROTO:
+ case -ESHUTDOWN:
+ return;
+
+ default:
+ dev_info(dev->udev->dev.parent,
+ "Rx URB aborted (%d)\n", urb->status);
+ goto resubmit_urb;
+ }
+
+ while (pos < urb->actual_length) {
+ struct esd_usb_msg *msg;
+
+ msg = (struct esd_usb_msg *)(urb->transfer_buffer + pos);
+
+ switch (msg->msg.hdr.cmd) {
+ case CMD_CAN_RX:
+ if (msg->msg.rx.net >= dev->net_count) {
+ dev_err(dev->udev->dev.parent, "format error\n");
+ break;
+ }
+
+ esd_usb_rx_can_msg(dev->nets[msg->msg.rx.net], msg);
+ break;
+
+ case CMD_CAN_TX:
+ if (msg->msg.txdone.net >= dev->net_count) {
+ dev_err(dev->udev->dev.parent, "format error\n");
+ break;
+ }
+
+ esd_usb_tx_done_msg(dev->nets[msg->msg.txdone.net],
+ msg);
+ break;
+ }
+
+ pos += msg->msg.hdr.len << 2;
+
+ if (pos > urb->actual_length) {
+ dev_err(dev->udev->dev.parent, "format error\n");
+ break;
+ }
+ }
+
+resubmit_urb:
+ usb_fill_bulk_urb(urb, dev->udev, usb_rcvbulkpipe(dev->udev, 1),
+ urb->transfer_buffer, RX_BUFFER_SIZE,
+ esd_usb_read_bulk_callback, dev);
+
+ retval = usb_submit_urb(urb, GFP_ATOMIC);
+ if (retval == -ENODEV) {
+ for (i = 0; i < dev->net_count; i++) {
+ if (dev->nets[i])
+ netif_device_detach(dev->nets[i]->netdev);
+ }
+ } else if (retval) {
+ dev_err(dev->udev->dev.parent,
+ "failed resubmitting read bulk urb: %d\n", retval);
+ }
+}
+
+/* callback for bulk IN urb */
+static void esd_usb_write_bulk_callback(struct urb *urb)
+{
+ struct esd_tx_urb_context *context = urb->context;
+ struct esd_usb_net_priv *priv;
+ struct net_device *netdev;
+ size_t size = sizeof(struct esd_usb_msg);
+
+ WARN_ON(!context);
+
+ priv = context->priv;
+ netdev = priv->netdev;
+
+ /* free up our allocated buffer */
+ usb_free_coherent(urb->dev, size,
+ urb->transfer_buffer, urb->transfer_dma);
+
+ if (!netif_device_present(netdev))
+ return;
+
+ if (urb->status)
+ netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
+
+ netif_trans_update(netdev);
+}
+
+static ssize_t firmware_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_interface *intf = to_usb_interface(d);
+ struct esd_usb *dev = usb_get_intfdata(intf);
+
+ return sprintf(buf, "%d.%d.%d\n",
+ (dev->version >> 12) & 0xf,
+ (dev->version >> 8) & 0xf,
+ dev->version & 0xff);
+}
+static DEVICE_ATTR_RO(firmware);
+
+static ssize_t hardware_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_interface *intf = to_usb_interface(d);
+ struct esd_usb *dev = usb_get_intfdata(intf);
+
+ return sprintf(buf, "%d.%d.%d\n",
+ (dev->version >> 28) & 0xf,
+ (dev->version >> 24) & 0xf,
+ (dev->version >> 16) & 0xff);
+}
+static DEVICE_ATTR_RO(hardware);
+
+static ssize_t nets_show(struct device *d,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_interface *intf = to_usb_interface(d);
+ struct esd_usb *dev = usb_get_intfdata(intf);
+
+ return sprintf(buf, "%d", dev->net_count);
+}
+static DEVICE_ATTR_RO(nets);
+
+static int esd_usb_send_msg(struct esd_usb *dev, struct esd_usb_msg *msg)
+{
+ int actual_length;
+
+ return usb_bulk_msg(dev->udev,
+ usb_sndbulkpipe(dev->udev, 2),
+ msg,
+ msg->msg.hdr.len << 2,
+ &actual_length,
+ 1000);
+}
+
+static int esd_usb_wait_msg(struct esd_usb *dev,
+ struct esd_usb_msg *msg)
+{
+ int actual_length;
+
+ return usb_bulk_msg(dev->udev,
+ usb_rcvbulkpipe(dev->udev, 1),
+ msg,
+ sizeof(*msg),
+ &actual_length,
+ 1000);
+}
+
+static int esd_usb_setup_rx_urbs(struct esd_usb *dev)
+{
+ int i, err = 0;
+
+ if (dev->rxinitdone)
+ return 0;
+
+ for (i = 0; i < MAX_RX_URBS; i++) {
+ struct urb *urb = NULL;
+ u8 *buf = NULL;
+ dma_addr_t buf_dma;
+
+ /* create a URB, and a buffer for it */
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ err = -ENOMEM;
+ break;
+ }
+
+ buf = usb_alloc_coherent(dev->udev, RX_BUFFER_SIZE, GFP_KERNEL,
+ &buf_dma);
+ if (!buf) {
+ dev_warn(dev->udev->dev.parent,
+ "No memory left for USB buffer\n");
+ err = -ENOMEM;
+ goto freeurb;
+ }
+
+ urb->transfer_dma = buf_dma;
+
+ usb_fill_bulk_urb(urb, dev->udev,
+ usb_rcvbulkpipe(dev->udev, 1),
+ buf, RX_BUFFER_SIZE,
+ esd_usb_read_bulk_callback, dev);
+ urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+ usb_anchor_urb(urb, &dev->rx_submitted);
+
+ err = usb_submit_urb(urb, GFP_KERNEL);
+ if (err) {
+ usb_unanchor_urb(urb);
+ usb_free_coherent(dev->udev, RX_BUFFER_SIZE, buf,
+ urb->transfer_dma);
+ goto freeurb;
+ }
+
+ dev->rxbuf[i] = buf;
+ dev->rxbuf_dma[i] = buf_dma;
+
+freeurb:
+ /* Drop reference, USB core will take care of freeing it */
+ usb_free_urb(urb);
+ if (err)
+ break;
+ }
+
+ /* Did we submit any URBs */
+ if (i == 0) {
+ dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
+ return err;
+ }
+
+ /* Warn if we've couldn't transmit all the URBs */
+ if (i < MAX_RX_URBS) {
+ dev_warn(dev->udev->dev.parent,
+ "rx performance may be slow\n");
+ }
+
+ dev->rxinitdone = 1;
+ return 0;
+}
+
+/* Start interface */
+static int esd_usb_start(struct esd_usb_net_priv *priv)
+{
+ struct esd_usb *dev = priv->usb;
+ struct net_device *netdev = priv->netdev;
+ struct esd_usb_msg *msg;
+ int err, i;
+
+ msg = kmalloc(sizeof(*msg), GFP_KERNEL);
+ if (!msg) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ /* Enable all IDs
+ * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
+ * Each bit represents one 11 bit CAN identifier. A set bit
+ * enables reception of the corresponding CAN identifier. A cleared
+ * bit disabled this identifier. An additional bitmask value
+ * following the CAN 2.0A bits is used to enable reception of
+ * extended CAN frames. Only the LSB of this final mask is checked
+ * for the complete 29 bit ID range. The IDADD message also allows
+ * filter configuration for an ID subset. In this case you can add
+ * the number of the starting bitmask (0..64) to the filter.option
+ * field followed by only some bitmasks.
+ */
+ msg->msg.hdr.cmd = CMD_IDADD;
+ msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
+ msg->msg.filter.net = priv->index;
+ msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
+ for (i = 0; i < ESD_MAX_ID_SEGMENT; i++)
+ msg->msg.filter.mask[i] = cpu_to_le32(0xffffffff);
+ /* enable 29bit extended IDs */
+ msg->msg.filter.mask[ESD_MAX_ID_SEGMENT] = cpu_to_le32(0x00000001);
+
+ err = esd_usb_send_msg(dev, msg);
+ if (err)
+ goto out;
+
+ err = esd_usb_setup_rx_urbs(dev);
+ if (err)
+ goto out;
+
+ priv->can.state = CAN_STATE_ERROR_ACTIVE;
+
+out:
+ if (err == -ENODEV)
+ netif_device_detach(netdev);
+ if (err)
+ netdev_err(netdev, "couldn't start device: %d\n", err);
+
+ kfree(msg);
+ return err;
+}
+
+static void unlink_all_urbs(struct esd_usb *dev)
+{
+ struct esd_usb_net_priv *priv;
+ int i, j;
+
+ usb_kill_anchored_urbs(&dev->rx_submitted);
+
+ for (i = 0; i < MAX_RX_URBS; ++i)
+ usb_free_coherent(dev->udev, RX_BUFFER_SIZE,
+ dev->rxbuf[i], dev->rxbuf_dma[i]);
+
+ for (i = 0; i < dev->net_count; i++) {
+ priv = dev->nets[i];
+ if (priv) {
+ usb_kill_anchored_urbs(&priv->tx_submitted);
+ atomic_set(&priv->active_tx_jobs, 0);
+
+ for (j = 0; j < MAX_TX_URBS; j++)
+ priv->tx_contexts[j].echo_index = MAX_TX_URBS;
+ }
+ }
+}
+
+static int esd_usb_open(struct net_device *netdev)
+{
+ struct esd_usb_net_priv *priv = netdev_priv(netdev);
+ int err;
+
+ /* common open */
+ err = open_candev(netdev);
+ if (err)
+ return err;
+
+ /* finally start device */
+ err = esd_usb_start(priv);
+ if (err) {
+ netdev_warn(netdev, "couldn't start device: %d\n", err);
+ close_candev(netdev);
+ return err;
+ }
+
+ netif_start_queue(netdev);
+
+ return 0;
+}
+
+static netdev_tx_t esd_usb_start_xmit(struct sk_buff *skb,
+ struct net_device *netdev)
+{
+ struct esd_usb_net_priv *priv = netdev_priv(netdev);
+ struct esd_usb *dev = priv->usb;
+ struct esd_tx_urb_context *context = NULL;
+ struct net_device_stats *stats = &netdev->stats;
+ struct can_frame *cf = (struct can_frame *)skb->data;
+ struct esd_usb_msg *msg;
+ struct urb *urb;
+ u8 *buf;
+ int i, err;
+ int ret = NETDEV_TX_OK;
+ size_t size = sizeof(struct esd_usb_msg);
+
+ if (can_dev_dropped_skb(netdev, skb))
+ return NETDEV_TX_OK;
+
+ /* create a URB, and a buffer for it, and copy the data to the URB */
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!urb) {
+ stats->tx_dropped++;
+ dev_kfree_skb(skb);
+ goto nourbmem;
+ }
+
+ buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
+ &urb->transfer_dma);
+ if (!buf) {
+ netdev_err(netdev, "No memory left for USB buffer\n");
+ stats->tx_dropped++;
+ dev_kfree_skb(skb);
+ goto nobufmem;
+ }
+
+ msg = (struct esd_usb_msg *)buf;
+
+ msg->msg.hdr.len = 3; /* minimal length */
+ msg->msg.hdr.cmd = CMD_CAN_TX;
+ msg->msg.tx.net = priv->index;
+ msg->msg.tx.dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
+ msg->msg.tx.id = cpu_to_le32(cf->can_id & CAN_ERR_MASK);
+
+ if (cf->can_id & CAN_RTR_FLAG)
+ msg->msg.tx.dlc |= ESD_RTR;
+
+ if (cf->can_id & CAN_EFF_FLAG)
+ msg->msg.tx.id |= cpu_to_le32(ESD_EXTID);
+
+ for (i = 0; i < cf->len; i++)
+ msg->msg.tx.data[i] = cf->data[i];
+
+ msg->msg.hdr.len += (cf->len + 3) >> 2;
+
+ for (i = 0; i < MAX_TX_URBS; i++) {
+ if (priv->tx_contexts[i].echo_index == MAX_TX_URBS) {
+ context = &priv->tx_contexts[i];
+ break;
+ }
+ }
+
+ /* This may never happen */
+ if (!context) {
+ netdev_warn(netdev, "couldn't find free context\n");
+ ret = NETDEV_TX_BUSY;
+ goto releasebuf;
+ }
+
+ context->priv = priv;
+ context->echo_index = i;
+
+ /* hnd must not be 0 - MSB is stripped in txdone handling */
+ msg->msg.tx.hnd = 0x80000000 | i; /* returned in TX done message */
+
+ usb_fill_bulk_urb(urb, dev->udev, usb_sndbulkpipe(dev->udev, 2), buf,
+ msg->msg.hdr.len << 2,
+ esd_usb_write_bulk_callback, context);
+
+ urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
+
+ usb_anchor_urb(urb, &priv->tx_submitted);
+
+ can_put_echo_skb(skb, netdev, context->echo_index, 0);
+
+ atomic_inc(&priv->active_tx_jobs);
+
+ /* Slow down tx path */
+ if (atomic_read(&priv->active_tx_jobs) >= MAX_TX_URBS)
+ netif_stop_queue(netdev);
+
+ err = usb_submit_urb(urb, GFP_ATOMIC);
+ if (err) {
+ can_free_echo_skb(netdev, context->echo_index, NULL);
+
+ atomic_dec(&priv->active_tx_jobs);
+ usb_unanchor_urb(urb);
+
+ stats->tx_dropped++;
+
+ if (err == -ENODEV)
+ netif_device_detach(netdev);
+ else
+ netdev_warn(netdev, "failed tx_urb %d\n", err);
+
+ goto releasebuf;
+ }
+
+ netif_trans_update(netdev);
+
+ /* Release our reference to this URB, the USB core will eventually free
+ * it entirely.
+ */
+ usb_free_urb(urb);
+
+ return NETDEV_TX_OK;
+
+releasebuf:
+ usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
+
+nobufmem:
+ usb_free_urb(urb);
+
+nourbmem:
+ return ret;
+}
+
+static int esd_usb_close(struct net_device *netdev)
+{
+ struct esd_usb_net_priv *priv = netdev_priv(netdev);
+ struct esd_usb_msg *msg;
+ int i;
+
+ msg = kmalloc(sizeof(*msg), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ /* Disable all IDs (see esd_usb_start()) */
+ msg->msg.hdr.cmd = CMD_IDADD;
+ msg->msg.hdr.len = 2 + ESD_MAX_ID_SEGMENT;
+ msg->msg.filter.net = priv->index;
+ msg->msg.filter.option = ESD_ID_ENABLE; /* start with segment 0 */
+ for (i = 0; i <= ESD_MAX_ID_SEGMENT; i++)
+ msg->msg.filter.mask[i] = 0;
+ if (esd_usb_send_msg(priv->usb, msg) < 0)
+ netdev_err(netdev, "sending idadd message failed\n");
+
+ /* set CAN controller to reset mode */
+ msg->msg.hdr.len = 2;
+ msg->msg.hdr.cmd = CMD_SETBAUD;
+ msg->msg.setbaud.net = priv->index;
+ msg->msg.setbaud.rsvd = 0;
+ msg->msg.setbaud.baud = cpu_to_le32(ESD_USB_NO_BAUDRATE);
+ if (esd_usb_send_msg(priv->usb, msg) < 0)
+ netdev_err(netdev, "sending setbaud message failed\n");
+
+ priv->can.state = CAN_STATE_STOPPED;
+
+ netif_stop_queue(netdev);
+
+ close_candev(netdev);
+
+ kfree(msg);
+
+ return 0;
+}
+
+static const struct net_device_ops esd_usb_netdev_ops = {
+ .ndo_open = esd_usb_open,
+ .ndo_stop = esd_usb_close,
+ .ndo_start_xmit = esd_usb_start_xmit,
+ .ndo_change_mtu = can_change_mtu,
+};
+
+static const struct ethtool_ops esd_usb_ethtool_ops = {
+ .get_ts_info = ethtool_op_get_ts_info,
+};
+
+static const struct can_bittiming_const esd_usb2_bittiming_const = {
+ .name = "esd_usb2",
+ .tseg1_min = ESD_USB2_TSEG1_MIN,
+ .tseg1_max = ESD_USB2_TSEG1_MAX,
+ .tseg2_min = ESD_USB2_TSEG2_MIN,
+ .tseg2_max = ESD_USB2_TSEG2_MAX,
+ .sjw_max = ESD_USB2_SJW_MAX,
+ .brp_min = ESD_USB2_BRP_MIN,
+ .brp_max = ESD_USB2_BRP_MAX,
+ .brp_inc = ESD_USB2_BRP_INC,
+};
+
+static int esd_usb2_set_bittiming(struct net_device *netdev)
+{
+ struct esd_usb_net_priv *priv = netdev_priv(netdev);
+ struct can_bittiming *bt = &priv->can.bittiming;
+ struct esd_usb_msg *msg;
+ int err;
+ u32 canbtr;
+ int sjw_shift;
+
+ canbtr = ESD_USB_UBR;
+ if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
+ canbtr |= ESD_USB_LOM;
+
+ canbtr |= (bt->brp - 1) & (ESD_USB2_BRP_MAX - 1);
+
+ if (le16_to_cpu(priv->usb->udev->descriptor.idProduct) ==
+ USB_CANUSBM_PRODUCT_ID)
+ sjw_shift = ESD_USBM_SJW_SHIFT;
+ else
+ sjw_shift = ESD_USB2_SJW_SHIFT;
+
+ canbtr |= ((bt->sjw - 1) & (ESD_USB2_SJW_MAX - 1))
+ << sjw_shift;
+ canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
+ & (ESD_USB2_TSEG1_MAX - 1))
+ << ESD_USB2_TSEG1_SHIFT;
+ canbtr |= ((bt->phase_seg2 - 1) & (ESD_USB2_TSEG2_MAX - 1))
+ << ESD_USB2_TSEG2_SHIFT;
+ if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
+ canbtr |= ESD_USB2_3_SAMPLES;
+
+ msg = kmalloc(sizeof(*msg), GFP_KERNEL);
+ if (!msg)
+ return -ENOMEM;
+
+ msg->msg.hdr.len = 2;
+ msg->msg.hdr.cmd = CMD_SETBAUD;
+ msg->msg.setbaud.net = priv->index;
+ msg->msg.setbaud.rsvd = 0;
+ msg->msg.setbaud.baud = cpu_to_le32(canbtr);
+
+ netdev_info(netdev, "setting BTR=%#x\n", canbtr);
+
+ err = esd_usb_send_msg(priv->usb, msg);
+
+ kfree(msg);
+ return err;
+}
+
+static int esd_usb_get_berr_counter(const struct net_device *netdev,
+ struct can_berr_counter *bec)
+{
+ struct esd_usb_net_priv *priv = netdev_priv(netdev);
+
+ bec->txerr = priv->bec.txerr;
+ bec->rxerr = priv->bec.rxerr;
+
+ return 0;
+}
+
+static int esd_usb_set_mode(struct net_device *netdev, enum can_mode mode)
+{
+ switch (mode) {
+ case CAN_MODE_START:
+ netif_wake_queue(netdev);
+ break;
+
+ default:
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static int esd_usb_probe_one_net(struct usb_interface *intf, int index)
+{
+ struct esd_usb *dev = usb_get_intfdata(intf);
+ struct net_device *netdev;
+ struct esd_usb_net_priv *priv;
+ int err = 0;
+ int i;
+
+ netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
+ if (!netdev) {
+ dev_err(&intf->dev, "couldn't alloc candev\n");
+ err = -ENOMEM;
+ goto done;
+ }
+
+ priv = netdev_priv(netdev);
+
+ init_usb_anchor(&priv->tx_submitted);
+ atomic_set(&priv->active_tx_jobs, 0);
+
+ for (i = 0; i < MAX_TX_URBS; i++)
+ priv->tx_contexts[i].echo_index = MAX_TX_URBS;
+
+ priv->usb = dev;
+ priv->netdev = netdev;
+ priv->index = index;
+
+ priv->can.state = CAN_STATE_STOPPED;
+ priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
+ CAN_CTRLMODE_CC_LEN8_DLC;
+
+ if (le16_to_cpu(dev->udev->descriptor.idProduct) ==
+ USB_CANUSBM_PRODUCT_ID)
+ priv->can.clock.freq = ESD_USBM_CAN_CLOCK;
+ else {
+ priv->can.clock.freq = ESD_USB2_CAN_CLOCK;
+ priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
+ }
+
+ priv->can.bittiming_const = &esd_usb2_bittiming_const;
+ priv->can.do_set_bittiming = esd_usb2_set_bittiming;
+ priv->can.do_set_mode = esd_usb_set_mode;
+ priv->can.do_get_berr_counter = esd_usb_get_berr_counter;
+
+ netdev->flags |= IFF_ECHO; /* we support local echo */
+
+ netdev->netdev_ops = &esd_usb_netdev_ops;
+ netdev->ethtool_ops = &esd_usb_ethtool_ops;
+
+ SET_NETDEV_DEV(netdev, &intf->dev);
+ netdev->dev_id = index;
+
+ err = register_candev(netdev);
+ if (err) {
+ dev_err(&intf->dev, "couldn't register CAN device: %d\n", err);
+ free_candev(netdev);
+ err = -ENOMEM;
+ goto done;
+ }
+
+ dev->nets[index] = priv;
+ netdev_info(netdev, "device %s registered\n", netdev->name);
+
+done:
+ return err;
+}
+
+/* probe function for new USB devices
+ *
+ * check version information and number of available
+ * CAN interfaces
+ */
+static int esd_usb_probe(struct usb_interface *intf,
+ const struct usb_device_id *id)
+{
+ struct esd_usb *dev;
+ struct esd_usb_msg *msg;
+ int i, err;
+
+ dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+ if (!dev) {
+ err = -ENOMEM;
+ goto done;
+ }
+
+ dev->udev = interface_to_usbdev(intf);
+
+ init_usb_anchor(&dev->rx_submitted);
+
+ usb_set_intfdata(intf, dev);
+
+ msg = kmalloc(sizeof(*msg), GFP_KERNEL);
+ if (!msg) {
+ err = -ENOMEM;
+ goto free_msg;
+ }
+
+ /* query number of CAN interfaces (nets) */
+ msg->msg.hdr.cmd = CMD_VERSION;
+ msg->msg.hdr.len = 2;
+ msg->msg.version.rsvd = 0;
+ msg->msg.version.flags = 0;
+ msg->msg.version.drv_version = 0;
+
+ err = esd_usb_send_msg(dev, msg);
+ if (err < 0) {
+ dev_err(&intf->dev, "sending version message failed\n");
+ goto free_msg;
+ }
+
+ err = esd_usb_wait_msg(dev, msg);
+ if (err < 0) {
+ dev_err(&intf->dev, "no version message answer\n");
+ goto free_msg;
+ }
+
+ dev->net_count = (int)msg->msg.version_reply.nets;
+ dev->version = le32_to_cpu(msg->msg.version_reply.version);
+
+ if (device_create_file(&intf->dev, &dev_attr_firmware))
+ dev_err(&intf->dev,
+ "Couldn't create device file for firmware\n");
+
+ if (device_create_file(&intf->dev, &dev_attr_hardware))
+ dev_err(&intf->dev,
+ "Couldn't create device file for hardware\n");
+
+ if (device_create_file(&intf->dev, &dev_attr_nets))
+ dev_err(&intf->dev,
+ "Couldn't create device file for nets\n");
+
+ /* do per device probing */
+ for (i = 0; i < dev->net_count; i++)
+ esd_usb_probe_one_net(intf, i);
+
+free_msg:
+ kfree(msg);
+ if (err)
+ kfree(dev);
+done:
+ return err;
+}
+
+/* called by the usb core when the device is removed from the system */
+static void esd_usb_disconnect(struct usb_interface *intf)
+{
+ struct esd_usb *dev = usb_get_intfdata(intf);
+ struct net_device *netdev;
+ int i;
+
+ device_remove_file(&intf->dev, &dev_attr_firmware);
+ device_remove_file(&intf->dev, &dev_attr_hardware);
+ device_remove_file(&intf->dev, &dev_attr_nets);
+
+ usb_set_intfdata(intf, NULL);
+
+ if (dev) {
+ for (i = 0; i < dev->net_count; i++) {
+ if (dev->nets[i]) {
+ netdev = dev->nets[i]->netdev;
+ unregister_netdev(netdev);
+ free_candev(netdev);
+ }
+ }
+ unlink_all_urbs(dev);
+ kfree(dev);
+ }
+}
+
+/* usb specific object needed to register this driver with the usb subsystem */
+static struct usb_driver esd_usb_driver = {
+ .name = KBUILD_MODNAME,
+ .probe = esd_usb_probe,
+ .disconnect = esd_usb_disconnect,
+ .id_table = esd_usb_table,
+};
+
+module_usb_driver(esd_usb_driver);