usb_8dev: Add support for USB2CAN interface from 8 devices

Add device driver for USB2CAN interface from "8 devices"
(http://www.8devices.com).

Signed-off-by Bernd Krumboeck <[email protected]>

---
 drivers/net/can/usb/Kconfig    |    6 +
 drivers/net/can/usb/Makefile   |    1 +
 drivers/net/can/usb/usb_8dev.c | 1089
++++++++++++++++++++++++++++++++++++++++
 3 files changed, 1096 insertions(+)
 create mode 100644 drivers/net/can/usb/usb_8dev.c

drivers/net/can/usb/Kconfig +6 -0

index a4e4bee..2162233 100644
@@ -48,4 +48,10 @@ config CAN_PEAK_USB
       This driver supports the PCAN-USB and PCAN-USB Pro adapters
       from PEAK-System Technik (http://www.peak-system.com).
 
+config CAN_8DEV_USB
+    tristate "8 devices USB2CAN interface"
+    ---help---
+      This driver supports the USB2CAN interface
+      from 8 devices (http://www.8devices.com).
+
 endmenu

drivers/net/can/usb/Makefile +1 -0

index 80a2ee4..becef46 100644
@@ -6,5 +6,6 @@ obj-$(CONFIG_CAN_EMS_USB) += ems_usb.o
 obj-$(CONFIG_CAN_ESD_USB2) += esd_usb2.o
 obj-$(CONFIG_CAN_KVASER_USB) += kvaser_usb.o
 obj-$(CONFIG_CAN_PEAK_USB) += peak_usb/
+obj-$(CONFIG_CAN_8DEV_USB) += usb_8dev.o
 
 ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG

drivers/net/can/usb/usb_8dev.c new file +7 -0

new file mode 100644
index 0000000..b3a7eee
@@ -0,0 +1,1089 @@
+/*
+ * CAN driver for "8 devices" USB2CAN converter
+ *
+ * Copyright (C) 2012 Bernd Krumboeck ([email protected])
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published

drivers/net/can/usb/usb_8dev.c new file +2 -0

+ *
+ * This driver is inspired by the 3.2.0 version of

drivers/net/can/usb/ems_usb.c
+ * and drivers/net/can/usb/esd_usb2.c
+ *
+ * Many thanks to Gerhard Bertelsmann ([email protected])
+ * for testing and fixing this driver. Also many thanks to "8 devices",
+ * who were very cooperative and answered my questions.
+ */

On 12/04/2012 11:43 PM, Bernd Krumboeck wrote:

Quoted 1 line · Bernd Krumboeck

                ^^^^^^^^

btw: your clock is wrong by about 1h :)

drivers/net/can/usb/usb_8dev.c new file +11 -0

+/* Send open command to device */
+static int usb_8dev_cmd_open(struct usb_8dev *dev)
+{
+    struct can_bittiming *bt = &dev->can.bittiming;
+    struct usb_8dev_cmd_msg outmsg;
+    struct usb_8dev_cmd_msg inmsg;
+    u32 flags = 0;
+    u32 beflags;
+    u16 bebrp;
+    u32 ctrlmode = dev->can.ctrlmode;
+

drivers/net/can/usb/usb_8dev.c new file +13 -0

+    outmsg.data[1] = bt->phase_seg2;
+    outmsg.data[2] = bt->sjw;
+
+    /* BRP */
+    bebrp = cpu_to_be16((u16) bt->brp);
+    memcpy(&outmsg.data[3], &bebrp, sizeof(bebrp));
+
+    /* flags */
+    beflags = cpu_to_be32(flags);
+    memcpy(&outmsg.data[5], &beflags, sizeof(beflags));
+
+    return usb_8dev_send_cmd(dev, &outmsg, &inmsg);
+}

drivers/net/can/usb/usb_8dev.c new file +48 -0

+
+/* Read data and status frames */
+static void usb_8dev_rx_can_msg(struct usb_8dev *dev,
+                struct usb_8dev_rx_msg *msg)
+{
+    struct can_frame *cf;
+    struct sk_buff *skb;
+    struct net_device_stats *stats = &dev->netdev->stats;
+
+    if (msg->type == USB_8DEV_TYPE_CAN_FRAME) {
+        skb = alloc_can_skb(dev->netdev, &cf);
+        if (!skb)
+            return;
+
+        cf->can_id = be32_to_cpu(msg->id);
+        cf->can_dlc = get_can_dlc(msg->dlc & 0xF);
+
+        if (msg->flags & USB_8DEV_EXTID)
+            cf->can_id |= CAN_EFF_FLAG;
+
+        if (msg->flags & USB_8DEV_RTR)
+            cf->can_id |= CAN_RTR_FLAG;
+        else
+            memcpy(cf->data, msg->data, cf->can_dlc);
+    } else if (msg->type == USB_8DEV_TYPE_ERROR_FRAME &&
+           msg->flags == USB_8DEV_ERR_FLAG) {
+
+        /*
+         * Error message:
+         * byte 0: Status
+         * byte 1: bit   7: Receive Passive
+         * byte 1: bit 0-6: Receive Error Counter
+         * byte 2: Transmit Error Counter
+         * byte 3: Always 0 (maybe reserved for future use)
+         */
+
+        u8 state = msg->data[0];
+        u8 rxerr = msg->data[1] & USB_8DEV_RP_MASK;
+        u8 txerr = msg->data[2];
+        int rx_errors = 0;
+        int tx_errors = 0;
+
+        skb = alloc_can_err_skb(dev->netdev, &cf);
+        if (!skb)
+            return;
+
+        switch (state) {
+        case USB_8DEV_STATUSMSG_OK:

drivers/net/can/usb/usb_8dev.c new file +26 -0

+            cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
+            dev->can.can_stats.bus_error++;
+            break;
+        }
+
+        switch (state) {
+        case USB_8DEV_STATUSMSG_ACK:
+            cf->can_id |= CAN_ERR_ACK;
+            tx_errors = 1;
+            break;
+        case USB_8DEV_STATUSMSG_CRC:
+            cf->data[2] |= CAN_ERR_PROT_BIT;
+            rx_errors = 1;
+            break;
+        case USB_8DEV_STATUSMSG_BIT0:
+            cf->data[2] |= CAN_ERR_PROT_BIT0;
+            tx_errors = 1;
+            break;
+        case USB_8DEV_STATUSMSG_BIT1:
+            cf->data[2] |= CAN_ERR_PROT_BIT1;
+            tx_errors = 1;
+            break;
+        case USB_8DEV_STATUSMSG_FORM:
+            cf->data[2] |= CAN_ERR_PROT_FORM;
+            rx_errors = 1;
+            break;

drivers/net/can/usb/usb_8dev.c new file +22 -0

+            cf->data[1] = (txerr > rxerr) ?
+                CAN_ERR_CRTL_TX_PASSIVE :
+                CAN_ERR_CRTL_RX_PASSIVE;
+            dev->can.can_stats.error_passive++;
+            break;
+        }
+
+        if (tx_errors) {
+            cf->data[2] |= CAN_ERR_PROT_TX;
+            stats->tx_errors++;
+        }
+
+        if (rx_errors)
+            stats->rx_errors++;
+
+        cf->data[6] = txerr;
+        cf->data[7] = rxerr;
+
+        dev->bec.txerr = txerr;
+        dev->bec.rxerr = rxerr;
+
+    } else {

drivers/net/can/usb/usb_8dev.c line 286

Quoted 3 lines

drivers/net/can/usb/usb_8dev.c new file +3 -0

+    outmsg.command = USB_8DEV_OPEN;
+    outmsg.opt1 = USB_8DEV_BAUD_MANUAL;
+    outmsg.data[0] = (bt->prop_seg + bt->phase_seg1);

Minor issue. Brackets not needed.

Quoted 3 lines

drivers/net/can/usb/usb_8dev.c new file +3 -0

+    outmsg.data[1] = bt->phase_seg2;
+    outmsg.data[2] = bt->sjw;
+

Quoted 9 lines · Wolfgang Grandegger

drivers/net/can/usb/usb_8dev.c line 286

Quoted 3 lines

drivers/net/can/usb/usb_8dev.c new file +3 -0

+    outmsg.command = USB_8DEV_OPEN;
+    outmsg.opt1 = USB_8DEV_BAUD_MANUAL;
+    outmsg.data[0] = (bt->prop_seg + bt->phase_seg1);

Minor issue. Brackets not needed.

Quoted 3 lines

drivers/net/can/usb/usb_8dev.c new file +3 -0

+    outmsg.data[1] = bt->phase_seg2;
+    outmsg.data[2] = bt->sjw;
+

That's correct from a compilers point of view.
But in this case i would preserve the [0] as it is better to read in conjunction with the two lines below ( ..[1] ..[2] )

The semantic has to be understood by humans ;-)

Quoted 12 lines · Oliver Hartkopp

Quoted 9 lines · Wolfgang Grandegger

Review

Quoted 3 lines

(quoted diff) +3 -0

+    outmsg.command = USB_8DEV_OPEN;
+    outmsg.opt1 = USB_8DEV_BAUD_MANUAL;
+    outmsg.data[0] = (bt->prop_seg + bt->phase_seg1);

Minor issue. Brackets not needed.

Quoted 3 lines

(quoted diff) +3 -0

+    outmsg.data[1] = bt->phase_seg2;
+    outmsg.data[2] = bt->sjw;
+

Quoted 5 lines

That's correct from a compilers point of view.
But in this case i would preserve the [0] as it is better to read in conjunction with the two lines below ( ..[1] ..[2] )

The semantic has to be understood by humans ;-)

I think Wolfgang was talking about the round bracket not the square bracket. :D

Add device driver for USB2CAN interface from "8 devices"
(http://www.8devices.com).