Subject: Re: [PATCH v5] can: kvaser_usb: Add support for Kvaser CAN/USB devices

From: Olivier Sobrie <[email-masked]>
Date: Tue, 20 Nov 2012 09:46:26 +0100

Hi Marc,

On Wed, Nov 07, 2012 at 09:29:05PM +0100, Marc Kleine-Budde wrote:
> On 10/02/2012 09:16 AM, Olivier Sobrie wrote:
> > This driver provides support for several Kvaser CAN/USB devices.
> > Such kind of devices supports up to three CAN network interfaces.
> > 
> > It has been tested with a Kvaser USB Leaf Light (one network interface)
> > connected to a pch_can interface.
> > The firmware version of the Kvaser device was 2.5.205.
> > 
> > List of Kvaser devices supported by the driver:
> >   - Kvaser Leaf Light
> >   - Kvaser Leaf Professional HS
> >   - Kvaser Leaf SemiPro HS
> >   - Kvaser Leaf Professional LS
> >   - Kvaser Leaf Professional SWC
> >   - Kvaser Leaf Professional LIN
> >   - Kvaser Leaf SemiPro LS
> >   - Kvaser Leaf SemiPro SWC
> >   - Kvaser Memorator II HS/HS
> >   - Kvaser USBcan Professional HS/HS
> >   - Kvaser Leaf Light GI
> >   - Kvaser Leaf Professional HS (OBD-II connector)
> >   - Kvaser Memorator Professional HS/LS
> >   - Kvaser Leaf Light "China"
> >   - Kvaser BlackBird SemiPro
> >   - Kvaser USBcan R
> > 
> > Signed-off-by: Daniel Berglund <[email-masked]>
> > Signed-off-by: Olivier Sobrie <[email-masked]>
> 
> Sorry I forgot about the review.
> Looks quite good, some comments inline.

Sorry for the late reply but I was in holiday during the last
3 weeks :-)
See my comments below.

> 
> > ---
> > Hi,
> > 
> > This new patch fixes the errors pointed out by Marc and Wolfgang.
> > 
> > Changes since v4:
> >  - add missing usb_free_urb()
> >  - put error message in a separate function
> >  - handle return code of kvaser_usb_init_one() in probe function
> > 
> > Olivier
> > 
> >  drivers/net/can/usb/Kconfig      |   29 +
> >  drivers/net/can/usb/Makefile     |    1 +
> >  drivers/net/can/usb/kvaser_usb.c | 1596 ++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 1626 insertions(+)
> >  create mode 100644 drivers/net/can/usb/kvaser_usb.c
> > 
> > diff --git a/drivers/net/can/usb/Kconfig b/drivers/net/can/usb/Kconfig
> > index 0a68768..a4e4bee 100644
> > --- a/drivers/net/can/usb/Kconfig
> > +++ b/drivers/net/can/usb/Kconfig
> > @@ -13,6 +13,35 @@ config CAN_ESD_USB2
> >            This driver supports the CAN-USB/2 interface
> >            from esd electronic system design gmbh (http://www.esd.eu).
> >  
> > +config CAN_KVASER_USB
> > +	tristate "Kvaser CAN/USB interface"
> > +	---help---
> > +	  This driver adds support for Kvaser CAN/USB devices like Kvaser
> > +	  Leaf Light.
> > +
> > +	  The driver gives support for the following devices:
> > +	    - Kvaser Leaf Light
> > +	    - Kvaser Leaf Professional HS
> > +	    - Kvaser Leaf SemiPro HS
> > +	    - Kvaser Leaf Professional LS
> > +	    - Kvaser Leaf Professional SWC
> > +	    - Kvaser Leaf Professional LIN
> > +	    - Kvaser Leaf SemiPro LS
> > +	    - Kvaser Leaf SemiPro SWC
> > +	    - Kvaser Memorator II HS/HS
> > +	    - Kvaser USBcan Professional HS/HS
> > +	    - Kvaser Leaf Light GI
> > +	    - Kvaser Leaf Professional HS (OBD-II connector)
> > +	    - Kvaser Memorator Professional HS/LS
> > +	    - Kvaser Leaf Light "China"
> > +	    - Kvaser BlackBird SemiPro
> > +	    - Kvaser USBcan R
> > +
> > +	  If unsure, say N.
> > +
> > +	  To compile this driver as a module, choose M here: the
> > +	  module will be called kvaser_usb.
> > +
> >  config CAN_PEAK_USB
> >  	tristate "PEAK PCAN-USB/USB Pro interfaces"
> >  	---help---
> > diff --git a/drivers/net/can/usb/Makefile b/drivers/net/can/usb/Makefile
> > index da6d1d3..80a2ee4 100644
> > --- a/drivers/net/can/usb/Makefile
> > +++ b/drivers/net/can/usb/Makefile
> > @@ -4,6 +4,7 @@
> >  
> >  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/
> >  
> >  ccflags-$(CONFIG_CAN_DEBUG_DEVICES) := -DDEBUG
> > diff --git a/drivers/net/can/usb/kvaser_usb.c b/drivers/net/can/usb/kvaser_usb.c
> > new file mode 100644
> > index 0000000..bd48807
> > --- /dev/null
> > +++ b/drivers/net/can/usb/kvaser_usb.c
> > @@ -0,0 +1,1596 @@
> > +/*
> > + * This program is free software; you can redistribute it and/or
> > + * modify it under the terms of the GNU General Public License as
> > + * published by the Free Software Foundation version 2.
> > + *
> > + * Parts of this driver are based on the following:
> > + *  - Kvaser linux leaf driver (version 4.78)
> > + *  - CAN driver for esd CAN-USB/2
> > + *
> > + * Copyright (C) 2002-2006 KVASER AB, Sweden. All rights reserved.
> > + * Copyright (C) 2010 Matthias Fuchs <[email-masked]>, esd gmbh
> > + * Copyright (C) 2012 Olivier Sobrie <[email-masked]>
> > + */
> > +
> > +#include <linux/init.h>
> > +#include <linux/completion.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>
> > +
> > +#define MAX_TX_URBS			16
> > +#define MAX_RX_URBS			4
> > +#define START_TIMEOUT			1000 /* msecs */
> > +#define STOP_TIMEOUT			1000 /* msecs */
> > +#define USB_SEND_TIMEOUT		1000 /* msecs */
> > +#define USB_RECV_TIMEOUT		1000 /* msecs */
> > +#define RX_BUFFER_SIZE			3072
> > +#define CAN_USB_CLOCK			8000000
> > +#define MAX_NET_DEVICES			3
> > +
> > +/* Kvaser USB devices */
> > +#define KVASER_VENDOR_ID		0x0bfd
> > +#define USB_LEAF_DEVEL_PRODUCT_ID	10
> > +#define USB_LEAF_LITE_PRODUCT_ID	11
> > +#define USB_LEAF_PRO_PRODUCT_ID		12
> > +#define USB_LEAF_SPRO_PRODUCT_ID	14
> > +#define USB_LEAF_PRO_LS_PRODUCT_ID	15
> > +#define USB_LEAF_PRO_SWC_PRODUCT_ID	16
> > +#define USB_LEAF_PRO_LIN_PRODUCT_ID	17
> > +#define USB_LEAF_SPRO_LS_PRODUCT_ID	18
> > +#define USB_LEAF_SPRO_SWC_PRODUCT_ID	19
> > +#define USB_MEMO2_DEVEL_PRODUCT_ID	22
> > +#define USB_MEMO2_HSHS_PRODUCT_ID	23
> > +#define USB_UPRO_HSHS_PRODUCT_ID	24
> > +#define USB_LEAF_LITE_GI_PRODUCT_ID	25
> > +#define USB_LEAF_PRO_OBDII_PRODUCT_ID	26
> > +#define USB_MEMO2_HSLS_PRODUCT_ID	27
> > +#define USB_LEAF_LITE_CH_PRODUCT_ID	28
> > +#define USB_BLACKBIRD_SPRO_PRODUCT_ID	29
> > +#define USB_OEM_MERCURY_PRODUCT_ID	34
> > +#define USB_OEM_LEAF_PRODUCT_ID		35
> > +#define USB_CAN_R_PRODUCT_ID		39
> > +
> > +/* USB devices features */
> > +#define KVASER_HAS_SILENT_MODE		BIT(0)
> > +#define KVASER_HAS_TXRX_ERRORS		BIT(1)
> > +
> > +/* Message header size */
> > +#define MSG_HEADER_LEN			2
> > +
> > +/* Can message flags */
> > +#define MSG_FLAG_ERROR_FRAME		BIT(0)
> > +#define MSG_FLAG_OVERRUN		BIT(1)
> > +#define MSG_FLAG_NERR			BIT(2)
> > +#define MSG_FLAG_WAKEUP			BIT(3)
> > +#define MSG_FLAG_REMOTE_FRAME		BIT(4)
> > +#define MSG_FLAG_RESERVED		BIT(5)
> > +#define MSG_FLAG_TX_ACK			BIT(6)
> > +#define MSG_FLAG_TX_REQUEST		BIT(7)
> > +
> > +/* Can states */
> > +#define M16C_STATE_BUS_RESET		BIT(0)
> > +#define M16C_STATE_BUS_ERROR		BIT(4)
> > +#define M16C_STATE_BUS_PASSIVE		BIT(5)
> > +#define M16C_STATE_BUS_OFF		BIT(6)
> > +
> > +/* Can msg ids */
> > +#define CMD_RX_STD_MESSAGE		12
> > +#define CMD_TX_STD_MESSAGE		13
> > +#define CMD_RX_EXT_MESSAGE		14
> > +#define CMD_TX_EXT_MESSAGE		15
> > +#define CMD_SET_BUS_PARAMS		16
> > +#define CMD_GET_BUS_PARAMS		17
> > +#define CMD_GET_BUS_PARAMS_REPLY	18
> > +#define CMD_GET_CHIP_STATE		19
> > +#define CMD_CHIP_STATE_EVENT		20
> > +#define CMD_SET_CTRL_MODE		21
> > +#define CMD_GET_CTRL_MODE		22
> > +#define CMD_GET_CTRL_MODE_REPLY		23
> > +#define CMD_RESET_CHIP			24
> > +#define CMD_RESET_CARD			25
> > +#define CMD_START_CHIP			26
> > +#define CMD_START_CHIP_REPLY		27
> > +#define CMD_STOP_CHIP			28
> > +#define CMD_STOP_CHIP_REPLY		29
> > +#define CMD_GET_CARD_INFO2		32
> > +#define CMD_GET_CARD_INFO		34
> > +#define CMD_GET_CARD_INFO_REPLY		35
> > +#define CMD_GET_SOFTWARE_INFO		38
> > +#define CMD_GET_SOFTWARE_INFO_REPLY	39
> > +#define CMD_ERROR_EVENT			45
> > +#define CMD_FLUSH_QUEUE			48
> > +#define CMD_RESET_ERROR_COUNTER		49
> > +#define CMD_TX_ACKNOWLEDGE		50
> > +#define CMD_CAN_ERROR_EVENT		51
> > +#define CMD_USB_THROTTLE		77
> > +#define CMD_LOG_MESSAGE			106
> > +
> > +/* error factors */
> > +#define M16C_EF_ACKE			BIT(0)
> > +#define M16C_EF_CRCE			BIT(1)
> > +#define M16C_EF_FORME			BIT(2)
> > +#define M16C_EF_STFE			BIT(3)
> > +#define M16C_EF_BITE0			BIT(4)
> > +#define M16C_EF_BITE1			BIT(5)
> > +#define M16C_EF_RCVE			BIT(6)
> > +#define M16C_EF_TRE			BIT(7)
> > +
> > +/* bittiming parameters */
> > +#define KVASER_USB_TSEG1_MIN		1
> > +#define KVASER_USB_TSEG1_MAX		16
> > +#define KVASER_USB_TSEG2_MIN		1
> > +#define KVASER_USB_TSEG2_MAX		8
> > +#define KVASER_USB_SJW_MAX		4
> > +#define KVASER_USB_BRP_MIN		1
> > +#define KVASER_USB_BRP_MAX		64
> > +#define KVASER_USB_BRP_INC		1
> > +
> > +/* ctrl modes */
> > +#define KVASER_CTRL_MODE_NORMAL		1
> > +#define KVASER_CTRL_MODE_SILENT		2
> > +#define KVASER_CTRL_MODE_SELFRECEPTION	3
> > +#define KVASER_CTRL_MODE_OFF		4
> > +
> > +struct kvaser_msg_simple {
> > +	u8 tid;
> > +	u8 channel;
> > +} __packed;
> > +
> > +struct kvaser_msg_cardinfo {
> > +	u8 tid;
> > +	u8 nchannels;
> > +	__le32 serial_number;
> > +	__le32 padding;
> > +	__le32 clock_resolution;
> > +	__le32 mfgdate;
> > +	u8 ean[8];
> > +	u8 hw_revision;
> > +	u8 usb_hs_mode;
> > +	__le16 padding2;
> > +} __packed;
> > +
> > +struct kvaser_msg_cardinfo2 {
> > +	u8 tid;
> > +	u8 channel;
> > +	u8 pcb_id[24];
> > +	__le32 oem_unlock_code;
> > +} __packed;
> > +
> > +struct kvaser_msg_softinfo {
> > +	u8 tid;
> > +	u8 channel;
> > +	__le32 sw_options;
> > +	__le32 fw_version;
> > +	__le16 max_outstanding_tx;
> > +	__le16 padding[9];
> > +} __packed;
> > +
> > +struct kvaser_msg_busparams {
> > +	u8 tid;
> > +	u8 channel;
> > +	__le32 bitrate;
> > +	u8 tseg1;
> > +	u8 tseg2;
> > +	u8 sjw;
> > +	u8 no_samp;
> > +} __packed;
> > +
> > +struct kvaser_msg_tx_can {
> > +	u8 channel;
> > +	u8 tid;
> > +	u8 msg[14];
> > +	u8 padding;
> > +	u8 flags;
> > +} __packed;
> > +
> > +struct kvaser_msg_rx_can {
> > +	u8 channel;
> > +	u8 flag;
> > +	__le16 time[3];
> > +	u8 msg[14];
> > +} __packed;
> > +
> > +struct kvaser_msg_chip_state_event {
> > +	u8 tid;
> > +	u8 channel;
> > +	__le16 time[3];
> > +	u8 tx_errors_count;
> > +	u8 rx_errors_count;
> > +	u8 status;
> > +	u8 padding[3];
> > +} __packed;
> > +
> > +struct kvaser_msg_tx_acknowledge {
> > +	u8 channel;
> > +	u8 tid;
> > +	__le16 time[3];
> > +	u8 flags;
> > +	u8 time_offset;
> > +} __packed;
> > +
> > +struct kvaser_msg_error_event {
> > +	u8 tid;
> > +	u8 flags;
> > +	__le16 time[3];
> > +	u8 channel;
> > +	u8 padding;
> > +	u8 tx_errors_count;
> > +	u8 rx_errors_count;
> > +	u8 status;
> > +	u8 error_factor;
> > +} __packed;
> > +
> > +struct kvaser_msg_ctrl_mode {
> > +	u8 tid;
> > +	u8 channel;
> > +	u8 ctrl_mode;
> > +	u8 padding[3];
> > +} __packed;
> > +
> > +struct kvaser_msg_flush_queue {
> > +	u8 tid;
> > +	u8 channel;
> > +	u8 flags;
> > +	u8 padding[3];
> > +} __packed;
> > +
> > +struct kvaser_msg_log_message {
> > +	u8 channel;
> > +	u8 flags;
> > +	__le16 time[3];
> > +	u8 dlc;
> > +	u8 time_offset;
> > +	__le32 id;
> > +	u8 data[8];
> > +} __packed;
> > +
> > +struct kvaser_msg {
> > +	u8 len;
> > +	u8 id;
> > +	union	{
> > +		struct kvaser_msg_simple simple;
> > +		struct kvaser_msg_cardinfo cardinfo;
> > +		struct kvaser_msg_cardinfo2 cardinfo2;
> > +		struct kvaser_msg_softinfo softinfo;
> > +		struct kvaser_msg_busparams busparams;
> > +		struct kvaser_msg_tx_can tx_can;
> > +		struct kvaser_msg_rx_can rx_can;
> > +		struct kvaser_msg_chip_state_event chip_state_event;
> > +		struct kvaser_msg_tx_acknowledge tx_acknowledge;
> > +		struct kvaser_msg_error_event error_event;
> > +		struct kvaser_msg_ctrl_mode ctrl_mode;
> > +		struct kvaser_msg_flush_queue flush_queue;
> > +		struct kvaser_msg_log_message log_message;
> > +	} u;
> > +} __packed;
> > +
> > +struct kvaser_usb_tx_urb_context {
> > +	struct kvaser_usb_net_priv *priv;
> > +	u32 echo_index;
> > +	int dlc;
> > +};
> > +
> > +struct kvaser_usb {
> > +	struct usb_device *udev;
> > +	struct kvaser_usb_net_priv *nets[MAX_NET_DEVICES];
> > +
> > +	struct usb_endpoint_descriptor *bulk_in, *bulk_out;
> > +	struct usb_anchor rx_submitted;
> > +
> > +	u32 fw_version;
> > +	unsigned int nchannels;
> > +
> > +	bool rxinitdone;
> > +	void *rxbuf[MAX_RX_URBS];
> > +	dma_addr_t rxbuf_dma[MAX_RX_URBS];
> > +};
> > +
> > +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 kvaser_usb *dev;
> > +	struct net_device *netdev;
> > +	int channel;
> > +
> > +	struct can_berr_counter bec;
> > +};
> > +
> > +static struct usb_device_id kvaser_usb_table[] = {
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_DEVEL_PRODUCT_ID) },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_PRODUCT_ID) },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_LS_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_SWC_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_LIN_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_LS_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_SPRO_SWC_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_DEVEL_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_HSHS_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_UPRO_HSHS_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_GI_PRODUCT_ID) },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_OBDII_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS |
> > +			       KVASER_HAS_SILENT_MODE },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MEMO2_HSLS_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_CH_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_BLACKBIRD_SPRO_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_OEM_MERCURY_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_OEM_LEAF_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ USB_DEVICE(KVASER_VENDOR_ID, USB_CAN_R_PRODUCT_ID),
> > +		.driver_info = KVASER_HAS_TXRX_ERRORS },
> > +	{ }
> > +};
> > +MODULE_DEVICE_TABLE(usb, kvaser_usb_table);
> > +
> > +static inline int kvaser_usb_send_msg(const struct kvaser_usb *dev,
> > +				      struct kvaser_msg *msg)
> > +{
> > +	int actual_len;
> > +
> > +	return usb_bulk_msg(dev->udev,
> > +			    usb_sndbulkpipe(dev->udev,
> > +					dev->bulk_out->bEndpointAddress),
> > +			    msg, msg->len, &actual_len,
> > +			    USB_SEND_TIMEOUT);
> > +}
> > +
> > +static int kvaser_usb_wait_msg(const struct kvaser_usb *dev, u8 id,
> > +			       struct kvaser_msg *msg)
> > +{
> > +	struct kvaser_msg *tmp;
> > +	void *buf;
> > +	int actual_len;
> > +	int err;
> > +	int pos = 0;
> > +
> > +	buf = kzalloc(RX_BUFFER_SIZE, GFP_KERNEL);
> > +	if (!buf)
> > +		return -ENOMEM;
> > +
> > +	err = usb_bulk_msg(dev->udev,
> > +			   usb_rcvbulkpipe(dev->udev,
> > +					   dev->bulk_in->bEndpointAddress),
> > +			   buf, RX_BUFFER_SIZE, &actual_len,
> > +			   USB_RECV_TIMEOUT);
> > +	if (err < 0)
> > +		goto end;
> > +
> > +	while (pos <= actual_len - MSG_HEADER_LEN) {
> > +		tmp = buf + pos;
> > +
> > +		if (!tmp->len)
> > +			break;
> > +
> > +		if (pos + tmp->len > actual_len) {
> > +			dev_err(dev->udev->dev.parent, "Format error\n");
> > +			break;
> > +		}
> > +
> > +		if (tmp->id == id) {
> > +			memcpy(msg, tmp, tmp->len);
> > +			goto end;
> > +		}
> > +
> > +		pos += tmp->len;
> > +	}
> > +
> > +	err = -EINVAL;
> > +
> > +end:
> > +	kfree(buf);
> > +
> > +	return err;
> > +}
> > +
> > +static int kvaser_usb_send_simple_msg(const struct kvaser_usb *dev,
> > +				      u8 msg_id, int channel)
> > +{
> > +	struct kvaser_msg msg = {
> > +		.len = MSG_HEADER_LEN + sizeof(struct kvaser_msg_simple),
> > +		.id = msg_id,
> > +		.u.simple.channel = channel,
> > +		.u.simple.tid = 0xff,
> > +	};
> > +
> > +	return kvaser_usb_send_msg(dev, &msg);
> > +}
> > +
> > +static int kvaser_usb_get_software_info(struct kvaser_usb *dev)
> > +{
> > +	struct kvaser_msg msg;
> > +	int err;
> > +
> > +	err = kvaser_usb_send_simple_msg(dev, CMD_GET_SOFTWARE_INFO, 0);
> > +	if (err)
> > +		return err;
> > +
> > +	err = kvaser_usb_wait_msg(dev, CMD_GET_SOFTWARE_INFO_REPLY, &msg);
> > +	if (err)
> > +		return err;
> > +
> > +	dev->fw_version = le32_to_cpu(msg.u.softinfo.fw_version);
> > +
> > +	return 0;
> > +}
> > +
> > +static int kvaser_usb_get_card_info(struct kvaser_usb *dev)
> > +{
> > +	struct kvaser_msg msg;
> > +	int err;
> > +
> > +	err = kvaser_usb_send_simple_msg(dev, CMD_GET_CARD_INFO, 0);
> > +	if (err)
> > +		return err;
> > +
> > +	err = kvaser_usb_wait_msg(dev, CMD_GET_CARD_INFO_REPLY, &msg);
> > +	if (err)
> > +		return err;
> > +
> > +	dev->nchannels = msg.u.cardinfo.nchannels;
> > +
> > +	return 0;
> > +}
> > +
> > +static void kvaser_usb_tx_acknowledge(const struct kvaser_usb *dev,
> > +				      const struct kvaser_msg *msg)
> > +{
> > +	struct net_device_stats *stats;
> > +	struct kvaser_usb_tx_urb_context *context;
> > +	struct kvaser_usb_net_priv *priv;
> > +	struct sk_buff *skb;
> > +	struct can_frame *cf;
> > +	u8 channel = msg->u.tx_acknowledge.channel;
> > +	u8 tid = msg->u.tx_acknowledge.tid;
> > +
> > +	if (channel >= dev->nchannels) {
> > +		dev_err(dev->udev->dev.parent,
> > +			"Invalid channel number (%d)\n", channel);
> > +		return;
> > +	}
> > +
> > +	priv = dev->nets[channel];
> > +
> > +	if (!netif_device_present(priv->netdev))
> > +		return;
> > +
> > +	stats = &priv->netdev->stats;
> > +
> > +	context = &priv->tx_contexts[tid % MAX_TX_URBS];
> > +
> > +	/* Sometimes the state change doesn't come after a bus-off event */
> > +	if (priv->can.restart_ms &&
> > +	    (priv->can.state >= CAN_STATE_BUS_OFF)) {
> > +		skb = alloc_can_err_skb(priv->netdev, &cf);
> > +		if (skb) {
> > +			cf->can_id |= CAN_ERR_RESTARTED;
> > +			netif_rx(skb);
> > +
> > +			stats->rx_packets++;
> > +			stats->rx_bytes += cf->can_dlc;
> > +		} else {
> > +			netdev_err(priv->netdev,
> > +				   "No memory left for err_skb\n");
> > +		}
> > +
> > +		priv->can.can_stats.restarts++;
> > +		netif_carrier_on(priv->netdev);
> > +
> > +		priv->can.state = CAN_STATE_ERROR_ACTIVE;
> > +	}
> > +
> > +	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);
> > +
> > +	netif_wake_queue(priv->netdev);
> > +}
> > +
> > +static void kvaser_usb_simple_msg_callback(struct urb *urb)
> > +{
> > +	struct net_device *netdev = urb->context;
> > +
> > +	kfree(urb->transfer_buffer);
> > +
> > +	if (urb->status)
> > +		netdev_warn(netdev, "urb status received: %d\n",
> > +			    urb->status);
> > +}
> > +
> > +static int kvaser_usb_simple_msg_async(struct kvaser_usb_net_priv *priv,
> > +				       u8 msg_id)
> > +{
> > +	struct kvaser_usb *dev = priv->dev;
> > +	struct net_device *netdev = priv->netdev;
> > +	struct kvaser_msg *msg;
> > +	struct urb *urb;
> > +	void *buf;
> > +	int err;
> > +
> > +	urb = usb_alloc_urb(0, GFP_ATOMIC);
> > +	if (!urb) {
> > +		netdev_err(netdev, "No memory left for URBs\n");
> > +		return -ENOMEM;
> > +	}
> > +
> > +	buf = kmalloc(sizeof(struct kvaser_msg), GFP_ATOMIC);
> > +	if (!buf) {
> > +		netdev_err(netdev, "No memory left for USB buffer\n");
> > +		usb_free_urb(urb);
> > +		return -ENOMEM;
> > +	}
> > +
> > +	msg = (struct kvaser_msg *)buf;
> > +	msg->len = MSG_HEADER_LEN + sizeof(struct kvaser_msg_simple);
> > +	msg->id = msg_id;
> > +	msg->u.simple.channel = priv->channel;
> > +
> > +	usb_fill_bulk_urb(urb, dev->udev,
> > +			  usb_sndbulkpipe(dev->udev,
> > +					  dev->bulk_out->bEndpointAddress),
> > +			  buf, msg->len,
> > +			  kvaser_usb_simple_msg_callback, priv);
> > +	usb_anchor_urb(urb, &priv->tx_submitted);
> > +
> > +	err = usb_submit_urb(urb, GFP_ATOMIC);
> > +	if (err) {
> > +		netdev_err(netdev, "Error transmitting URB\n");
> > +		usb_unanchor_urb(urb);
> > +		usb_free_urb(urb);
> > +		kfree(buf);
> > +		return err;
> > +	}
> > +
> > +	usb_free_urb(urb);
> > +
> > +	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(const struct kvaser_usb *dev,
> > +				const struct kvaser_msg *msg)
> > +{
> > +	struct can_frame *cf;
> > +	struct sk_buff *skb;
> > +	struct net_device_stats *stats;
> > +	struct kvaser_usb_net_priv *priv;
> > +	unsigned int new_state;
> > +	u8 channel, status, txerr, rxerr, error_factor;
> > +
> > +	switch (msg->id) {
> > +	case CMD_CAN_ERROR_EVENT:
> > +		channel = msg->u.error_event.channel;
> > +		status =  msg->u.error_event.status;
> > +		txerr = msg->u.error_event.tx_errors_count;
> > +		rxerr = msg->u.error_event.rx_errors_count;
> > +		error_factor = msg->u.error_event.error_factor;
> > +		break;
> > +	case CMD_LOG_MESSAGE:
> > +		channel = msg->u.log_message.channel;
> > +		status = msg->u.log_message.data[0];
> > +		txerr = msg->u.log_message.data[2];
> > +		rxerr = msg->u.log_message.data[3];
> > +		error_factor = msg->u.log_message.data[1];
> > +		break;
> > +	case CMD_CHIP_STATE_EVENT:
> > +		channel = msg->u.chip_state_event.channel;
> > +		status =  msg->u.chip_state_event.status;
> > +		txerr = msg->u.chip_state_event.tx_errors_count;
> > +		rxerr = msg->u.chip_state_event.rx_errors_count;
> > +		error_factor = 0;
> > +		break;
> > +	default:
> > +		dev_err(dev->udev->dev.parent, "Invalid msg id (%d)\n",
> > +			msg->id);
> > +		return;
> > +	}
> > +
> > +	if (channel >= dev->nchannels) {
> > +		dev_err(dev->udev->dev.parent,
> > +			"Invalid channel number (%d)\n", channel);
> > +		return;
> > +	}
> > +
> > +	priv = dev->nets[channel];
> > +	stats = &priv->netdev->stats;
> > +
> > +	if (status & M16C_STATE_BUS_RESET) {
> > +		kvaser_usb_unlink_tx_urbs(priv);
> > +		return;
> > +	}
> > +
> > +	skb = alloc_can_err_skb(priv->netdev, &cf);
> > +	if (!skb) {
> > +		stats->rx_dropped++;
> > +		return;
> > +	}
> > +
> > +	new_state = priv->can.state;
> > +
> > +	netdev_dbg(priv->netdev, "Error status: 0x%02x\n", status);
> > +
> > +	if (status & M16C_STATE_BUS_OFF) {
> > +		cf->can_id |= CAN_ERR_BUSOFF;
> > +
> > +		priv->can.can_stats.bus_off++;
> > +		if (!priv->can.restart_ms)
> > +			kvaser_usb_simple_msg_async(priv, CMD_STOP_CHIP);
> > +
> > +		netif_carrier_off(priv->netdev);
> > +
> > +		new_state = CAN_STATE_BUS_OFF;
> > +	} else if (status & M16C_STATE_BUS_PASSIVE) {
> > +		if (priv->can.state != CAN_STATE_ERROR_PASSIVE) {
> > +			cf->can_id |= CAN_ERR_CRTL;
> > +
> > +			if (txerr || rxerr)
> > +				cf->data[1] = (txerr > rxerr)
> > +						? CAN_ERR_CRTL_TX_PASSIVE
> > +						: CAN_ERR_CRTL_RX_PASSIVE;
> > +			else
> > +				cf->data[1] = CAN_ERR_CRTL_TX_PASSIVE |
> > +					      CAN_ERR_CRTL_RX_PASSIVE;
> > +
> > +			priv->can.can_stats.error_passive++;
> > +		}
> > +
> > +		new_state = CAN_STATE_ERROR_PASSIVE;
> > +	}
> > +
> > +	if (status == M16C_STATE_BUS_ERROR) {
> > +		if ((priv->can.state < CAN_STATE_ERROR_WARNING) &&
> > +		    ((txerr >= 96) || (rxerr >= 96))) {
> > +			cf->can_id |= CAN_ERR_CRTL;
> > +			cf->data[1] = (txerr > rxerr)
> > +					? CAN_ERR_CRTL_TX_WARNING
> > +					: CAN_ERR_CRTL_RX_WARNING;
> > +
> > +			priv->can.can_stats.error_warning++;
> > +			new_state = CAN_STATE_ERROR_WARNING;
> > +		} else if (priv->can.state > CAN_STATE_ERROR_ACTIVE) {
> > +			cf->can_id |= CAN_ERR_PROT;
> > +			cf->data[2] = CAN_ERR_PROT_ACTIVE;
> > +
> > +			new_state = CAN_STATE_ERROR_ACTIVE;
> > +		}
> > +	}
> > +
> > +	if (!status) {
> > +		cf->can_id |= CAN_ERR_PROT;
> > +		cf->data[2] = CAN_ERR_PROT_ACTIVE;
> > +
> > +		new_state = CAN_STATE_ERROR_ACTIVE;
> > +	}
> > +
> > +	if (priv->can.restart_ms &&
> > +	    (priv->can.state >= CAN_STATE_BUS_OFF) &&
> > +	    (new_state < CAN_STATE_BUS_OFF)) {
> > +		cf->can_id |= CAN_ERR_RESTARTED;
> > +		netif_carrier_on(priv->netdev);
> > +
> > +		priv->can.can_stats.restarts++;
> > +	}
> > +
> > +	if (error_factor) {
> > +		priv->can.can_stats.bus_error++;
> > +		stats->rx_errors++;
> > +
> > +		cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
> > +
> > +		if (error_factor & M16C_EF_ACKE)
> > +			cf->data[3] |= (CAN_ERR_PROT_LOC_ACK);
> > +		if (error_factor & M16C_EF_CRCE)
> > +			cf->data[3] |= (CAN_ERR_PROT_LOC_CRC_SEQ |
> > +					CAN_ERR_PROT_LOC_CRC_DEL);
> > +		if (error_factor & M16C_EF_FORME)
> > +			cf->data[2] |= CAN_ERR_PROT_FORM;
> > +		if (error_factor & M16C_EF_STFE)
> > +			cf->data[2] |= CAN_ERR_PROT_STUFF;
> > +		if (error_factor & M16C_EF_BITE0)
> > +			cf->data[2] |= CAN_ERR_PROT_BIT0;
> > +		if (error_factor & M16C_EF_BITE1)
> > +			cf->data[2] |= CAN_ERR_PROT_BIT1;
> > +		if (error_factor & M16C_EF_TRE)
> > +			cf->data[2] |= CAN_ERR_PROT_TX;
> > +	}
> > +
> > +	cf->data[6] = txerr;
> > +	cf->data[7] = rxerr;
> > +
> > +	priv->bec.txerr = txerr;
> > +	priv->bec.rxerr = rxerr;
> > +
> > +	priv->can.state = new_state;
> > +
> > +	netif_rx(skb);
> > +
> > +	stats->rx_packets++;
> > +	stats->rx_bytes += cf->can_dlc;
> > +}
> > +
> > +static void kvaser_usb_rx_can_err(const struct kvaser_usb_net_priv *priv,
> > +				  const struct kvaser_msg *msg)
> > +{
> > +	struct can_frame *cf;
> > +	struct sk_buff *skb;
> > +	struct net_device_stats *stats = &priv->netdev->stats;
> > +
> > +	if (msg->u.rx_can.flag & (MSG_FLAG_ERROR_FRAME |
> > +					 MSG_FLAG_NERR)) {
> > +		netdev_err(priv->netdev, "Unknow error (flags: 0x%02x)\n",
> > +			   msg->u.rx_can.flag);
> > +
> > +		stats->rx_errors++;
> > +		return;
> > +	}
> > +
> > +	if (msg->u.rx_can.flag & MSG_FLAG_OVERRUN) {
> > +		skb = alloc_can_err_skb(priv->netdev, &cf);
> > +		if (!skb) {
> > +			stats->tx_dropped++;
> 
> Should be rx, as we are in the rx function.

Ok I'll fix that.

> 
> > +			return;
> > +		}
> > +
> > +		cf->can_id |= CAN_ERR_CRTL;
> > +		cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
> > +
> > +		stats->rx_over_errors++;
> > +		stats->rx_errors++;
> > +
> > +		netif_rx(skb);
> > +
> > +		stats->rx_packets++;
> > +		stats->rx_bytes += cf->can_dlc;
> > +	}
> > +}
> > +
> > +static void kvaser_usb_rx_can_msg(const struct kvaser_usb *dev,
> > +				  const struct kvaser_msg *msg)
> > +{
> > +	struct kvaser_usb_net_priv *priv;
> > +	struct can_frame *cf;
> > +	struct sk_buff *skb;
> > +	struct net_device_stats *stats;
> > +	u8 channel = msg->u.rx_can.channel;
> > +
> > +	if (channel >= dev->nchannels) {
> > +		dev_err(dev->udev->dev.parent,
> > +			"Invalid channel number (%d)\n", channel);
> > +		return;
> > +	}
> > +
> > +	priv = dev->nets[channel];
> > +	stats = &priv->netdev->stats;
> > +
> > +	if (msg->u.rx_can.flag & (MSG_FLAG_ERROR_FRAME | MSG_FLAG_NERR |
> > +				  MSG_FLAG_OVERRUN)) {
> > +		kvaser_usb_rx_can_err(priv, msg);
> > +		return;
> > +	} else if (msg->u.rx_can.flag & ~MSG_FLAG_REMOTE_FRAME) {
> > +		netdev_warn(priv->netdev,
> > +			    "Unhandled frame (flags: 0x%02x)",
> > +			    msg->u.rx_can.flag);
> > +		return;
> > +	}
> > +
> > +	skb = alloc_can_skb(priv->netdev, &cf);
> > +	if (!skb) {
> > +		stats->tx_dropped++;
> > +		return;
> > +	}
> > +
> > +	cf->can_id = ((msg->u.rx_can.msg[0] & 0x1f) << 6) |
> > +		     (msg->u.rx_can.msg[1] & 0x3f);
> > +	cf->can_dlc = get_can_dlc(msg->u.rx_can.msg[5]);
> > +
> > +	if (msg->id == CMD_RX_EXT_MESSAGE) {
> > +		cf->can_id <<= 18;
> > +		cf->can_id |= ((msg->u.rx_can.msg[2] & 0x0f) << 14) |
> > +			      ((msg->u.rx_can.msg[3] & 0xff) << 6) |
> > +			      (msg->u.rx_can.msg[4] & 0x3f);
> > +		cf->can_id |= CAN_EFF_FLAG;
> > +	}
> > +
> > +	if (msg->u.rx_can.flag & MSG_FLAG_REMOTE_FRAME)
> > +		cf->can_id |= CAN_RTR_FLAG;
> > +	else
> > +		memcpy(cf->data, &msg->u.rx_can.msg[6], cf->can_dlc);
> > +
> > +	netif_rx(skb);
> > +
> > +	stats->rx_packets++;
> > +	stats->rx_bytes += cf->can_dlc;
> > +}
> > +
> > +static void kvaser_usb_start_chip_reply(const struct kvaser_usb *dev,
> > +					const struct kvaser_msg *msg)
> > +{
> > +	struct kvaser_usb_net_priv *priv;
> > +	u8 channel = msg->u.simple.channel;
> > +
> > +	if (channel >= dev->nchannels) {
> > +		dev_err(dev->udev->dev.parent,
> > +			"Invalid channel number (%d)\n", channel);
> > +		return;
> > +	}
> > +
> > +	priv = dev->nets[channel];
> > +
> > +	if (completion_done(&priv->start_comp) &&
> > +	    netif_queue_stopped(priv->netdev)) {
> > +		netif_wake_queue(priv->netdev);
> > +	} else {
> > +		netif_start_queue(priv->netdev);
> > +		complete(&priv->start_comp);
> > +	}
> > +}
> > +
> > +static void kvaser_usb_stop_chip_reply(const struct kvaser_usb *dev,
> > +				       const struct kvaser_msg *msg)
> > +{
> > +	struct kvaser_usb_net_priv *priv;
> > +	u8 channel = msg->u.simple.channel;
> > +
> > +	if (channel >= dev->nchannels) {
> > +		dev_err(dev->udev->dev.parent,
> > +			"Invalid channel number (%d)\n", channel);
> > +		return;
> > +	}
> > +
> > +	priv = dev->nets[channel];
> > +
> > +	complete(&priv->stop_comp);
> > +}
> > +
> > +static void kvaser_usb_handle_message(const struct kvaser_usb *dev,
> > +				      const struct kvaser_msg *msg)
> > +{
> > +	switch (msg->id) {
> > +	case CMD_START_CHIP_REPLY:
> > +		kvaser_usb_start_chip_reply(dev, msg);
> > +		break;
> > +
> > +	case CMD_STOP_CHIP_REPLY:
> > +		kvaser_usb_stop_chip_reply(dev, msg);
> > +		break;
> > +
> > +	case CMD_RX_STD_MESSAGE:
> > +	case CMD_RX_EXT_MESSAGE:
> > +		kvaser_usb_rx_can_msg(dev, msg);
> > +		break;
> > +
> > +	case CMD_CHIP_STATE_EVENT:
> > +	case CMD_CAN_ERROR_EVENT:
> > +		kvaser_usb_rx_error(dev, msg);
> > +		break;
> > +
> > +	case CMD_LOG_MESSAGE:
> > +		if (msg->u.log_message.flags & MSG_FLAG_ERROR_FRAME)
> > +			kvaser_usb_rx_error(dev, msg);
> > +		break;
> > +
> > +	case CMD_TX_ACKNOWLEDGE:
> > +		kvaser_usb_tx_acknowledge(dev, msg);
> > +		break;
> > +
> > +	default:
> > +		dev_warn(dev->udev->dev.parent,
> > +			 "Unhandled message (%d)\n", msg->id);
> > +		break;
> > +	}
> > +}
> > +
> > +static void kvaser_usb_read_bulk_callback(struct urb *urb)
> > +{
> > +	struct kvaser_usb *dev = urb->context;
> > +	struct kvaser_msg *msg;
> > +	int pos = 0;
> > +	int err, i;
> > +
> > +	switch (urb->status) {
> > +	case 0:
> > +		break;
> > +	case -ENOENT:
> > +	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 - MSG_HEADER_LEN) {
> > +		msg = urb->transfer_buffer + pos;
> > +
> > +		if (!msg->len)
> > +			break;
> > +
> > +		if (pos + msg->len > urb->actual_length) {
> > +			dev_err(dev->udev->dev.parent, "Format error\n");
> > +			break;
> > +		}
> > +
> > +		kvaser_usb_handle_message(dev, msg);
> > +
> > +		pos += msg->len;
> > +	}
> > +
> > +resubmit_urb:
> > +	usb_fill_bulk_urb(urb, dev->udev,
> > +			  usb_rcvbulkpipe(dev->udev,
> > +					  dev->bulk_in->bEndpointAddress),
> > +			  urb->transfer_buffer, RX_BUFFER_SIZE,
> > +			  kvaser_usb_read_bulk_callback, dev);
> > +
> > +	err = usb_submit_urb(urb, GFP_ATOMIC);
> > +	if (err == -ENODEV) {
> > +		for (i = 0; i < dev->nchannels; i++) {
> > +			if (!dev->nets[i])
> > +				continue;
> > +
> > +			netif_device_detach(dev->nets[i]->netdev);
> > +		}
> > +	} else if (err) {
> > +		dev_err(dev->udev->dev.parent,
> > +			"Failed resubmitting read bulk urb: %d\n", err);
> > +	}
> > +
> > +	return;
> > +}
> > +
> > +static int kvaser_usb_setup_rx_urbs(struct kvaser_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;
> > +
> > +		urb = usb_alloc_urb(0, GFP_KERNEL);
> > +		if (!urb) {
> > +			dev_warn(dev->udev->dev.parent,
> > +				 "No memory left for URBs\n");
> > +			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");
> > +			usb_free_urb(urb);
> > +			err = -ENOMEM;
> > +			break;
> > +		}
> > +
> > +		usb_fill_bulk_urb(urb, dev->udev,
> > +				  usb_rcvbulkpipe(dev->udev,
> > +					  dev->bulk_in->bEndpointAddress),
> > +				  buf, RX_BUFFER_SIZE,
> > +				  kvaser_usb_read_bulk_callback,
> > +				  dev);
> > +		urb->transfer_dma = buf_dma;
> > +		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,
> > +					  buf_dma);
> > +			usb_free_urb(urb);
> > +			break;
> > +		}
> > +
> > +		dev->rxbuf[i] = buf;
> > +		dev->rxbuf_dma[i] = buf_dma;
> > +
> > +		usb_free_urb(urb);
> > +	}
> > +
> > +	if (i == 0) {
> > +		dev_warn(dev->udev->dev.parent,
> > +			 "Cannot setup read URBs, error %d\n", err);
> > +		return err;
> > +	} else if (i < MAX_RX_URBS) {
> > +		dev_warn(dev->udev->dev.parent,
> > +			 "RX performances may be slow\n");
> > +	}
> > +
> > +	dev->rxinitdone = true;
> > +
> > +	return 0;
> > +}
> > +
> > +static int kvaser_usb_set_opt_mode(const struct kvaser_usb_net_priv *priv)
> > +{
> > +	struct kvaser_msg msg = {
> > +		.id = CMD_SET_CTRL_MODE,
> > +		.len = MSG_HEADER_LEN +
> > +		       sizeof(struct kvaser_msg_ctrl_mode),
> > +		.u.ctrl_mode.tid = 0xff,
> > +		.u.ctrl_mode.channel = priv->channel,
> > +	};
> > +
> > +	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
> > +		msg.u.ctrl_mode.ctrl_mode = KVASER_CTRL_MODE_SILENT;
> > +	else
> > +		msg.u.ctrl_mode.ctrl_mode = KVASER_CTRL_MODE_NORMAL;
> > +
> > +	return kvaser_usb_send_msg(priv->dev, &msg);
> > +}
> > +
> > +static int kvaser_usb_start_chip(struct kvaser_usb_net_priv *priv)
> > +{
> > +	int err;
> > +
> > +	init_completion(&priv->start_comp);
> > +
> > +	err = kvaser_usb_send_simple_msg(priv->dev, CMD_START_CHIP,
> > +					 priv->channel);
> > +	if (err)
> > +		return err;
> > +
> > +	if (!wait_for_completion_timeout(&priv->start_comp,
> > +					 msecs_to_jiffies(START_TIMEOUT)))
> > +		return -ETIMEDOUT;
> > +
> > +	return 0;
> > +}
> > +
> > +static int kvaser_usb_open(struct net_device *netdev)
> > +{
> > +	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
> > +	struct kvaser_usb *dev = priv->dev;
> > +	int err;
> > +
> > +	err = open_candev(netdev);
> > +	if (err)
> > +		return err;
> > +
> > +	err = kvaser_usb_setup_rx_urbs(dev);
> > +	if (err)
> > +		goto error;
> > +
> > +	err = kvaser_usb_set_opt_mode(priv);
> > +	if (err)
> > +		goto error;
> > +
> > +	err = kvaser_usb_start_chip(priv);
> > +	if (err) {
> > +		netdev_warn(netdev, "Cannot start device, error %d\n", err);
> > +		goto error;
> > +	}
> > +
> > +	priv->can.state = CAN_STATE_ERROR_ACTIVE;
> > +
> > +	return 0;
> > +
> > +error:
> > +	close_candev(netdev);
> > +	return err;
> > +}
> > +
> > +static void kvaser_usb_unlink_all_urbs(struct kvaser_usb *dev)
> > +{
> > +	int i;
> > +
> > +	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 < MAX_NET_DEVICES; i++) {
> > +		struct kvaser_usb_net_priv *priv = dev->nets[i];
> > +
> > +		if (priv)
> > +			kvaser_usb_unlink_tx_urbs(priv);
> > +	}
> > +}
> > +
> > +static int kvaser_usb_stop_chip(struct kvaser_usb_net_priv *priv)
> > +{
> > +	int err;
> > +
> > +	init_completion(&priv->stop_comp);
> > +
> > +	err = kvaser_usb_send_simple_msg(priv->dev, CMD_STOP_CHIP,
> > +					 priv->channel);
> > +	if (err)
> > +		return err;
> > +
> > +	if (!wait_for_completion_timeout(&priv->stop_comp,
> > +					 msecs_to_jiffies(STOP_TIMEOUT)))
> > +		return -ETIMEDOUT;
> > +
> > +	return 0;
> > +}
> > +
> > +static int kvaser_usb_flush_queue(struct kvaser_usb_net_priv *priv)
> > +{
> > +	struct kvaser_msg msg = {
> > +		.id = CMD_FLUSH_QUEUE,
> > +		.len = MSG_HEADER_LEN +
> > +		       sizeof(struct kvaser_msg_flush_queue),
> > +		.u.flush_queue.channel = priv->channel,
> > +		.u.flush_queue.flags = 0x00,
> > +	};
> > +
> > +	return kvaser_usb_send_msg(priv->dev, &msg);
> > +}
> > +
> > +static int kvaser_usb_close(struct net_device *netdev)
> > +{
> > +	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
> > +	struct kvaser_usb *dev = priv->dev;
> > +	int err;
> > +
> > +	netif_stop_queue(netdev);
> > +
> > +	err = kvaser_usb_flush_queue(priv);
> > +	if (err)
> > +		netdev_warn(netdev, "Cannot flush queue, error %d\n", err);
> > +
> > +	if (kvaser_usb_send_simple_msg(dev, CMD_RESET_CHIP, priv->channel))
> > +		netdev_warn(netdev, "Cannot reset card, error %d\n", err);
> > +
> > +	err = kvaser_usb_stop_chip(priv);
> > +	if (err)
> > +		netdev_warn(netdev, "Cannot stop device, error %d\n", err);
> > +
> > +	priv->can.state = CAN_STATE_STOPPED;
> > +	close_candev(priv->netdev);
> > +
> > +	return 0;
> > +}
> > +
> > +static void kvaser_usb_write_bulk_callback(struct urb *urb)
> > +{
> > +	struct kvaser_usb_tx_urb_context *context = urb->context;
> > +	struct kvaser_usb_net_priv *priv;
> > +	struct net_device *netdev;
> > +
> > +	if (WARN_ON(!context))
> > +		return;
> > +
> > +	priv = context->priv;
> > +	netdev = priv->netdev;
> > +
> > +	kfree(urb->transfer_buffer);
> > +
> > +	if (!netif_device_present(netdev))
> > +		return;
> > +
> > +	if (urb->status)
> > +		netdev_info(netdev, "Tx URB aborted (%d)\n", urb->status);
> > +}
> > +
> > +static netdev_tx_t kvaser_usb_start_xmit(struct sk_buff *skb,
> > +					 struct net_device *netdev)
> > +{
> > +	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
> > +	struct kvaser_usb *dev = priv->dev;
> > +	struct net_device_stats *stats = &netdev->stats;
> > +	struct can_frame *cf = (struct can_frame *)skb->data;
> > +	struct kvaser_usb_tx_urb_context *context = NULL;
> > +	struct urb *urb;
> > +	void *buf;
> > +	struct kvaser_msg *msg;
> > +	int i, err;
> > +	int ret = NETDEV_TX_OK;
> > +
> > +	if (can_dropped_invalid_skb(netdev, skb))
> > +		return NETDEV_TX_OK;
> > +
> > +	urb = usb_alloc_urb(0, GFP_ATOMIC);
> > +	if (!urb) {
> > +		netdev_err(netdev, "No memory left for URBs\n");
> > +		stats->tx_dropped++;
> 
> Move the dev_kfree_skb to the end and goto there.

I assume you mean doing something like that at the end of the function:
 releasebuf:
 	kfree(buf);
 nobufmem:
 	usb_free_urb(urb);
 nourbmem:
 	dev_kfree_skb(skb);
 	return ret;

If I do that it will give problems when the 'releasebuf' condition is
reached. The skb buffer will be freed twice. The skb is already freed
by the function can_free_echo_skb().

> 
> > +		dev_kfree_skb(skb);
> > +		return NETDEV_TX_OK;
> > +	}
> > +
> > +	buf = kmalloc(sizeof(struct kvaser_msg), GFP_ATOMIC);
> > +	if (!buf) {
> > +		netdev_err(netdev, "No memory left for USB buffer\n");
> > +		stats->tx_dropped++;
> You cann usb_free_urb twice...here and in the error handling at the end.

Indeed thanks.

> 
> > +		dev_kfree_skb(skb);
> > +		usb_free_urb(urb);
> > +		goto nobufmem;
> > +	}
> > +
> > +	msg = buf;
> > +	msg->len = MSG_HEADER_LEN + sizeof(struct kvaser_msg_tx_can);
> > +	msg->u.tx_can.flags = 0;
> > +	msg->u.tx_can.channel = priv->channel;
> > +
> > +	if (cf->can_id & CAN_EFF_FLAG) {
> > +		msg->id = CMD_TX_EXT_MESSAGE;
> > +		msg->u.tx_can.msg[0] = (cf->can_id >> 24) & 0x1f;
> > +		msg->u.tx_can.msg[1] = (cf->can_id >> 18) & 0x3f;
> > +		msg->u.tx_can.msg[2] = (cf->can_id >> 14) & 0x0f;
> > +		msg->u.tx_can.msg[3] = (cf->can_id >> 6) & 0xff;
> > +		msg->u.tx_can.msg[4] = cf->can_id & 0x3f;
> > +	} else {
> > +		msg->id = CMD_TX_STD_MESSAGE;
> > +		msg->u.tx_can.msg[0] = (cf->can_id >> 6) & 0x1f;
> > +		msg->u.tx_can.msg[1] = cf->can_id & 0x3f;
> > +	}
> > +
> > +	msg->u.tx_can.msg[5] = cf->can_dlc;
> > +	memcpy(&msg->u.tx_can.msg[6], cf->data, cf->can_dlc);
> > +
> > +	if (cf->can_id & CAN_RTR_FLAG)
> > +		msg->u.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) {
> > +			context = &priv->tx_contexts[i];
> > +			break;
> > +		}
> > +	}
> > +
> > +	if (!context) {
> > +		netdev_warn(netdev, "cannot find free context\n");
> > +		ret =  NETDEV_TX_BUSY;
> > +		goto releasebuf;
> > +	}
> > +
> > +	context->priv = priv;
> > +	context->echo_index = i;
> > +	context->dlc = cf->can_dlc;
> > +
> > +	msg->u.tx_can.tid = context->echo_index;
> > +
> > +	usb_fill_bulk_urb(urb, dev->udev,
> > +			  usb_sndbulkpipe(dev->udev,
> > +					  dev->bulk_out->bEndpointAddress),
> > +			  buf, msg->len,
> > +			  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)) {
> > +		can_free_echo_skb(netdev, context->echo_index);
> > +
> > +		atomic_dec(&priv->active_tx_urbs);
> > +		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;
> > +	}
> > +
> > +	usb_free_urb(urb);
> > +
> > +	return NETDEV_TX_OK;
> > +
> > +releasebuf:
> > +	kfree(buf);
> > +nobufmem:
> > +	usb_free_urb(urb);
> > +	return ret;
> > +}
> > +
> > +static const struct net_device_ops kvaser_usb_netdev_ops = {
> > +	.ndo_open = kvaser_usb_open,
> > +	.ndo_stop = kvaser_usb_close,
> > +	.ndo_start_xmit = kvaser_usb_start_xmit,
> > +};
> > +
> > +static struct can_bittiming_const kvaser_usb_bittiming_const = {
> > +	.name = "kvaser_usb",
> > +	.tseg1_min = KVASER_USB_TSEG1_MIN,
> > +	.tseg1_max = KVASER_USB_TSEG1_MAX,
> > +	.tseg2_min = KVASER_USB_TSEG2_MIN,
> > +	.tseg2_max = KVASER_USB_TSEG2_MAX,
> > +	.sjw_max = KVASER_USB_SJW_MAX,
> > +	.brp_min = KVASER_USB_BRP_MIN,
> > +	.brp_max = KVASER_USB_BRP_MAX,
> > +	.brp_inc = KVASER_USB_BRP_INC,
> > +};
> > +
> > +static int kvaser_usb_set_bittiming(struct net_device *netdev)
> > +{
> > +	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
> > +	struct can_bittiming *bt = &priv->can.bittiming;
> > +	struct kvaser_usb *dev = priv->dev;
> > +	struct kvaser_msg msg = {
> > +		.id = CMD_SET_BUS_PARAMS,
> > +		.len = MSG_HEADER_LEN +
> > +		       sizeof(struct kvaser_msg_busparams),
> > +		.u.busparams.channel = priv->channel,
> > +		.u.busparams.tid = 0xff,
> > +		.u.busparams.bitrate = cpu_to_le32(bt->bitrate),
> > +		.u.busparams.sjw = bt->sjw,
> > +		.u.busparams.tseg1 = bt->prop_seg + bt->phase_seg1,
> > +		.u.busparams.tseg2 = bt->phase_seg2,
> > +	};
> > +
> > +	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
> > +		msg.u.busparams.no_samp = 3;
> > +	else
> > +		msg.u.busparams.no_samp = 1;
> > +
> > +	return kvaser_usb_send_msg(dev, &msg);
> > +}
> > +
> > +static int kvaser_usb_set_mode(struct net_device *netdev,
> > +			       enum can_mode mode)
> > +{
> > +	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
> > +	int err;
> > +
> > +	switch (mode) {
> > +	case CAN_MODE_START:
> > +		err = kvaser_usb_simple_msg_async(priv, CMD_START_CHIP);
> > +		if (err)
> > +			return err;
> > +		break;
> > +	default:
> > +		return -EOPNOTSUPP;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static int kvaser_usb_get_berr_counter(const struct net_device *netdev,
> > +				       struct can_berr_counter *bec)
> > +{
> > +	struct kvaser_usb_net_priv *priv = netdev_priv(netdev);
> > +
> > +	*bec = priv->bec;
> > +
> > +	return 0;
> > +}
> > +
> > +static void kvaser_usb_remove_interfaces(struct kvaser_usb *dev)
> > +{
> > +	int i;
> > +
> > +	for (i = 0; i < dev->nchannels; i++) {
> > +		if (!dev->nets[i])
> > +			continue;
> > +
> > +		unregister_netdev(dev->nets[i]->netdev);
> > +	}
> > +
> > +	kvaser_usb_unlink_all_urbs(dev);
> > +
> > +	for (i = 0; i < dev->nchannels; i++) {
> > +		if (!dev->nets[i])
> > +			continue;
> > +
> > +		free_candev(dev->nets[i]->netdev);
> > +	}
> > +}
> > +
> > +static int kvaser_usb_init_one(struct usb_interface *intf,
> > +			       const struct usb_device_id *id, int channel)
> > +{
> > +	struct kvaser_usb *dev = usb_get_intfdata(intf);
> > +	struct net_device *netdev;
> > +	struct kvaser_usb_net_priv *priv;
> > +	int i, err;
> > +
> > +	netdev = alloc_candev(sizeof(*priv), MAX_TX_URBS);
> > +	if (!netdev) {
> > +		dev_err(&intf->dev, "Cannot alloc candev\n");
> > +		return -ENOMEM;
> > +	}
> > +
> > +	priv = netdev_priv(netdev);
> > +
> > +	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;
> > +
> > +	priv->can.state = CAN_STATE_STOPPED;
> > +	priv->can.clock.freq = CAN_USB_CLOCK;
> > +	priv->can.bittiming_const = &kvaser_usb_bittiming_const;
> > +	priv->can.do_set_bittiming = kvaser_usb_set_bittiming;
> > +	priv->can.do_set_mode = kvaser_usb_set_mode;
> > +	if (id->driver_info & KVASER_HAS_TXRX_ERRORS)
> > +		priv->can.do_get_berr_counter = kvaser_usb_get_berr_counter;
> > +	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
> > +	if (id->driver_info & KVASER_HAS_SILENT_MODE)
> > +		priv->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
> > +
> > +	netdev->flags |= IFF_ECHO;
> > +
> > +	netdev->netdev_ops = &kvaser_usb_netdev_ops;
> > +
> > +	SET_NETDEV_DEV(netdev, &intf->dev);
> > +
> > +	dev->nets[channel] = priv;
> > +
> > +	err = register_candev(netdev);
> > +	if (err) {
> > +		dev_err(&intf->dev, "Failed to register can device\n");
> > +		free_candev(netdev);
> > +		dev->nets[channel] = NULL;
> > +		return err;
> > +	}
> > +
> > +	netdev_dbg(netdev, "device registered\n");
> > +
> > +	return 0;
> > +}
> > +
> > +static void kvaser_usb_get_endpoints(const struct usb_interface *intf,
> > +				     struct usb_endpoint_descriptor **in,
> > +				     struct usb_endpoint_descriptor **out)
> > +{
> > +	const struct usb_host_interface *iface_desc;
> > +	struct usb_endpoint_descriptor *endpoint;
> > +	int i;
> > +
> > +	iface_desc = &intf->altsetting[0];
> > +
> > +	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
> > +		endpoint = &iface_desc->endpoint[i].desc;
> > +
> > +		if (usb_endpoint_is_bulk_in(endpoint))
> > +			*in = endpoint;
> > +
> > +		if (usb_endpoint_is_bulk_out(endpoint))
> > +			*out = endpoint;
> > +	}
> > +}
> > +
> > +static int kvaser_usb_probe(struct usb_interface *intf,
> > +			    const struct usb_device_id *id)
> > +{
> > +	struct kvaser_usb *dev;
> > +	int err = -ENOMEM;
> > +	int i;
> > +
> > +	dev = devm_kzalloc(&intf->dev, sizeof(*dev), GFP_KERNEL);
> > +	if (!dev)
> > +		return -ENOMEM;
> > +
> > +	kvaser_usb_get_endpoints(intf, &dev->bulk_in, &dev->bulk_out);
> > +	if (!dev->bulk_in || !dev->bulk_out) {
> > +		dev_err(&intf->dev, "Cannot get usb endpoint(s)");
> > +		return err;
> > +	}
> > +
> > +	dev->udev = interface_to_usbdev(intf);
> > +
> > +	init_usb_anchor(&dev->rx_submitted);
> > +
> > +	usb_set_intfdata(intf, dev);
> > +
> > +	for (i = 0; i < MAX_NET_DEVICES; i++)
> > +		kvaser_usb_send_simple_msg(dev, CMD_RESET_CHIP, i);
> > +
> > +	err = kvaser_usb_get_software_info(dev);
> > +	if (err) {
> > +		dev_err(&intf->dev,
> > +			"Cannot get software infos, error %d\n", err);
> > +		return err;
> > +	}
> > +
> > +	err = kvaser_usb_get_card_info(dev);
> > +	if (err) {
> > +		dev_err(&intf->dev,
> > +			"Cannot get card infos, error %d\n", err);
> > +		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) {
> > +			kvaser_usb_remove_interfaces(dev);
> > +			return err;
> > +		}
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void kvaser_usb_disconnect(struct usb_interface *intf)
> > +{
> > +	struct kvaser_usb *dev = usb_get_intfdata(intf);
> > +
> > +	usb_set_intfdata(intf, NULL);
> > +
> > +	if (!dev)
> > +		return;
> > +
> > +	kvaser_usb_remove_interfaces(dev);
> > +}
> > +
> > +static struct usb_driver kvaser_usb_driver = {
> > +	.name = "kvaser_usb",
> > +	.probe = kvaser_usb_probe,
> > +	.disconnect = kvaser_usb_disconnect,
> > +	.id_table = kvaser_usb_table
>                                   ^^^
> nitpick, please add a "," there.

Ok.

> > +};
> > 
> can you please add MODULE_DEVICE_TABLE(usb, kvaser_usb_table);

It is already present just after the kvaser_usb_table structure.

> 
> > +module_usb_driver(kvaser_usb_driver);
> > +
> > +MODULE_AUTHOR("Olivier Sobrie <[email-masked]>");
> > +MODULE_DESCRIPTION("CAN driver for Kvaser CAN/USB devices");
> > +MODULE_LICENSE("GPL v2");
> > 
> 
> Marc
> -- 
> Pengutronix e.K.                  | Marc Kleine-Budde           |
> Industrial Linux Solutions        | Phone: +49-231-2826-924     |
> Vertretung West/Dortmund          | Fax:   +49-5121-206917-5555 |
> Amtsgericht Hildesheim, HRA 2686  | http://www.pengutronix.de   |
> 

Thank you,

-- 
Olivier