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|
// SPDX-License-Identifier: GPL-2.0-only
/*
* CAN driver for PEAK System PCAN-USB adapter
* Derived from the PCAN project file driver/src/pcan_usb.c
*
* Copyright (C) 2003-2010 PEAK System-Technik GmbH
* Copyright (C) 2011-2012 Stephane Grosjean <s.grosjean@peak-system.com>
*
* Many thanks to Klaus Hitschler <klaus.hitschler@gmx.de>
*/
#include <linux/unaligned.h>
#include <linux/ethtool.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>
#include "pcan_usb_core.h"
/* PCAN-USB Endpoints */
#define PCAN_USB_EP_CMDOUT 1
#define PCAN_USB_EP_CMDIN (PCAN_USB_EP_CMDOUT | USB_DIR_IN)
#define PCAN_USB_EP_MSGOUT 2
#define PCAN_USB_EP_MSGIN (PCAN_USB_EP_MSGOUT | USB_DIR_IN)
/* PCAN-USB command struct */
#define PCAN_USB_CMD_FUNC 0
#define PCAN_USB_CMD_NUM 1
#define PCAN_USB_CMD_ARGS 2
#define PCAN_USB_CMD_ARGS_LEN 14
#define PCAN_USB_CMD_LEN (PCAN_USB_CMD_ARGS + \
PCAN_USB_CMD_ARGS_LEN)
/* PCAN-USB commands */
#define PCAN_USB_CMD_BITRATE 1
#define PCAN_USB_CMD_SET_BUS 3
#define PCAN_USB_CMD_DEVID 4
#define PCAN_USB_CMD_SN 6
#define PCAN_USB_CMD_REGISTER 9
#define PCAN_USB_CMD_EXT_VCC 10
#define PCAN_USB_CMD_ERR_FR 11
#define PCAN_USB_CMD_LED 12
/* PCAN_USB_CMD_SET_BUS number arg */
#define PCAN_USB_BUS_XCVER 2
#define PCAN_USB_BUS_SILENT_MODE 3
/* PCAN_USB_CMD_xxx functions */
#define PCAN_USB_GET 1
#define PCAN_USB_SET 2
/* PCAN-USB command timeout (ms.) */
#define PCAN_USB_COMMAND_TIMEOUT 1000
/* PCAN-USB startup timeout (ms.) */
#define PCAN_USB_STARTUP_TIMEOUT 10
/* PCAN-USB rx/tx buffers size */
#define PCAN_USB_RX_BUFFER_SIZE 64
#define PCAN_USB_TX_BUFFER_SIZE 64
#define PCAN_USB_MSG_HEADER_LEN 2
#define PCAN_USB_MSG_TX_CAN 2 /* Tx msg is a CAN frame */
/* PCAN-USB adapter internal clock (MHz) */
#define PCAN_USB_CRYSTAL_HZ 16000000
/* PCAN-USB USB message record status/len field */
#define PCAN_USB_STATUSLEN_TIMESTAMP (1 << 7)
#define PCAN_USB_STATUSLEN_INTERNAL (1 << 6)
#define PCAN_USB_STATUSLEN_EXT_ID (1 << 5)
#define PCAN_USB_STATUSLEN_RTR (1 << 4)
#define PCAN_USB_STATUSLEN_DLC (0xf)
/* PCAN-USB 4.1 CAN Id tx extended flags */
#define PCAN_USB_TX_SRR 0x01 /* SJA1000 SRR command */
#define PCAN_USB_TX_AT 0x02 /* SJA1000 AT command */
/* PCAN-USB error flags */
#define PCAN_USB_ERROR_TXFULL 0x01
#define PCAN_USB_ERROR_RXQOVR 0x02
#define PCAN_USB_ERROR_BUS_LIGHT 0x04
#define PCAN_USB_ERROR_BUS_HEAVY 0x08
#define PCAN_USB_ERROR_BUS_OFF 0x10
#define PCAN_USB_ERROR_RXQEMPTY 0x20
#define PCAN_USB_ERROR_QOVR 0x40
#define PCAN_USB_ERROR_TXQFULL 0x80
#define PCAN_USB_ERROR_BUS (PCAN_USB_ERROR_BUS_LIGHT | \
PCAN_USB_ERROR_BUS_HEAVY | \
PCAN_USB_ERROR_BUS_OFF)
/* SJA1000 modes */
#define SJA1000_MODE_NORMAL 0x00
#define SJA1000_MODE_INIT 0x01
/*
* tick duration = 42.666 us =>
* (tick_number * 44739243) >> 20 ~ (tick_number * 42666) / 1000
* accuracy = 10^-7
*/
#define PCAN_USB_TS_DIV_SHIFTER 20
#define PCAN_USB_TS_US_PER_TICK 44739243
/* PCAN-USB messages record types */
#define PCAN_USB_REC_ERROR 1
#define PCAN_USB_REC_ANALOG 2
#define PCAN_USB_REC_BUSLOAD 3
#define PCAN_USB_REC_TS 4
#define PCAN_USB_REC_BUSEVT 5
/* CAN bus events notifications selection mask */
#define PCAN_USB_ERR_RXERR 0x02 /* ask for rxerr counter */
#define PCAN_USB_ERR_TXERR 0x04 /* ask for txerr counter */
/* This mask generates an usb packet each time the state of the bus changes.
* In other words, its interest is to know which side among rx and tx is
* responsible of the change of the bus state.
*/
#define PCAN_USB_BERR_MASK (PCAN_USB_ERR_RXERR | PCAN_USB_ERR_TXERR)
/* identify bus event packets with rx/tx error counters */
#define PCAN_USB_ERR_CNT_DEC 0x00 /* counters are decreasing */
#define PCAN_USB_ERR_CNT_INC 0x80 /* counters are increasing */
/* private to PCAN-USB adapter */
struct pcan_usb {
struct peak_usb_device dev;
struct peak_time_ref time_ref;
struct timer_list restart_timer;
struct can_berr_counter bec;
};
/* incoming message context for decoding */
struct pcan_usb_msg_context {
u16 ts16;
u8 prev_ts8;
u8 *ptr;
u8 *end;
u8 rec_cnt;
u8 rec_idx;
u8 rec_ts_idx;
struct net_device *netdev;
struct pcan_usb *pdev;
};
/*
* send a command
*/
static int pcan_usb_send_cmd(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
{
int err;
int actual_length;
/* usb device unregistered? */
if (!(dev->state & PCAN_USB_STATE_CONNECTED))
return 0;
dev->cmd_buf[PCAN_USB_CMD_FUNC] = f;
dev->cmd_buf[PCAN_USB_CMD_NUM] = n;
if (p)
memcpy(dev->cmd_buf + PCAN_USB_CMD_ARGS,
p, PCAN_USB_CMD_ARGS_LEN);
err = usb_bulk_msg(dev->udev,
usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT),
dev->cmd_buf, PCAN_USB_CMD_LEN, &actual_length,
PCAN_USB_COMMAND_TIMEOUT);
if (err)
netdev_err(dev->netdev,
"sending cmd f=0x%x n=0x%x failure: %d\n",
f, n, err);
return err;
}
/*
* send a command then wait for its response
*/
static int pcan_usb_wait_rsp(struct peak_usb_device *dev, u8 f, u8 n, u8 *p)
{
int err;
int actual_length;
/* usb device unregistered? */
if (!(dev->state & PCAN_USB_STATE_CONNECTED))
return 0;
/* first, send command */
err = pcan_usb_send_cmd(dev, f, n, NULL);
if (err)
return err;
err = usb_bulk_msg(dev->udev,
usb_rcvbulkpipe(dev->udev, PCAN_USB_EP_CMDIN),
dev->cmd_buf, PCAN_USB_CMD_LEN, &actual_length,
PCAN_USB_COMMAND_TIMEOUT);
if (err)
netdev_err(dev->netdev,
"waiting rsp f=0x%x n=0x%x failure: %d\n", f, n, err);
else if (p)
memcpy(p, dev->cmd_buf + PCAN_USB_CMD_ARGS,
PCAN_USB_CMD_ARGS_LEN);
return err;
}
static int pcan_usb_set_sja1000(struct peak_usb_device *dev, u8 mode)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[1] = mode,
};
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_REGISTER, PCAN_USB_SET,
args);
}
static int pcan_usb_set_bus(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_SET_BUS, PCAN_USB_BUS_XCVER,
args);
}
static int pcan_usb_set_silent(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_SET_BUS,
PCAN_USB_BUS_SILENT_MODE, args);
}
/* send the cmd to be notified from bus errors */
static int pcan_usb_set_err_frame(struct peak_usb_device *dev, u8 err_mask)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = err_mask,
};
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_ERR_FR, PCAN_USB_SET, args);
}
static int pcan_usb_set_ext_vcc(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_EXT_VCC, PCAN_USB_SET, args);
}
static int pcan_usb_set_led(struct peak_usb_device *dev, u8 onoff)
{
u8 args[PCAN_USB_CMD_ARGS_LEN] = {
[0] = !!onoff,
};
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_LED, PCAN_USB_SET, args);
}
/*
* set bittiming value to can
*/
static int pcan_usb_set_bittiming(struct peak_usb_device *dev,
struct can_bittiming *bt)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
u8 btr0, btr1;
btr0 = ((bt->brp - 1) & 0x3f) | (((bt->sjw - 1) & 0x3) << 6);
btr1 = ((bt->prop_seg + bt->phase_seg1 - 1) & 0xf) |
(((bt->phase_seg2 - 1) & 0x7) << 4);
if (dev->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
btr1 |= 0x80;
netdev_info(dev->netdev, "setting BTR0=0x%02x BTR1=0x%02x\n",
btr0, btr1);
args[0] = btr1;
args[1] = btr0;
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_BITRATE, PCAN_USB_SET, args);
}
/*
* init/reset can
*/
static int pcan_usb_write_mode(struct peak_usb_device *dev, u8 onoff)
{
int err;
err = pcan_usb_set_bus(dev, onoff);
if (err)
return err;
if (!onoff) {
err = pcan_usb_set_sja1000(dev, SJA1000_MODE_INIT);
} else {
/* the PCAN-USB needs time to init */
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(msecs_to_jiffies(PCAN_USB_STARTUP_TIMEOUT));
}
return err;
}
/*
* handle end of waiting for the device to reset
*/
static void pcan_usb_restart(struct timer_list *t)
{
struct pcan_usb *pdev = from_timer(pdev, t, restart_timer);
struct peak_usb_device *dev = &pdev->dev;
/* notify candev and netdev */
peak_usb_restart_complete(dev);
}
/*
* handle the submission of the restart urb
*/
static void pcan_usb_restart_pending(struct urb *urb)
{
struct pcan_usb *pdev = urb->context;
/* the PCAN-USB needs time to restart */
mod_timer(&pdev->restart_timer,
jiffies + msecs_to_jiffies(PCAN_USB_STARTUP_TIMEOUT));
/* can delete usb resources */
peak_usb_async_complete(urb);
}
/*
* handle asynchronous restart
*/
static int pcan_usb_restart_async(struct peak_usb_device *dev, struct urb *urb,
u8 *buf)
{
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
if (timer_pending(&pdev->restart_timer))
return -EBUSY;
/* set bus on */
buf[PCAN_USB_CMD_FUNC] = 3;
buf[PCAN_USB_CMD_NUM] = 2;
buf[PCAN_USB_CMD_ARGS] = 1;
usb_fill_bulk_urb(urb, dev->udev,
usb_sndbulkpipe(dev->udev, PCAN_USB_EP_CMDOUT),
buf, PCAN_USB_CMD_LEN,
pcan_usb_restart_pending, pdev);
return usb_submit_urb(urb, GFP_ATOMIC);
}
/*
* read serial number from device
*/
static int pcan_usb_get_serial(struct peak_usb_device *dev, u32 *serial_number)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
int err;
err = pcan_usb_wait_rsp(dev, PCAN_USB_CMD_SN, PCAN_USB_GET, args);
if (err)
return err;
*serial_number = le32_to_cpup((__le32 *)args);
return 0;
}
/*
* read can channel id from device
*/
static int pcan_usb_get_can_channel_id(struct peak_usb_device *dev, u32 *can_ch_id)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
int err;
err = pcan_usb_wait_rsp(dev, PCAN_USB_CMD_DEVID, PCAN_USB_GET, args);
if (err)
netdev_err(dev->netdev, "getting can channel id failure: %d\n", err);
else
*can_ch_id = args[0];
return err;
}
/* set a new CAN channel id in the flash memory of the device */
static int pcan_usb_set_can_channel_id(struct peak_usb_device *dev, u32 can_ch_id)
{
u8 args[PCAN_USB_CMD_ARGS_LEN];
/* this kind of device supports 8-bit values only */
if (can_ch_id > U8_MAX)
return -EINVAL;
/* during the flash process the device disconnects during ~1.25 s.:
* prohibit access when interface is UP
*/
if (dev->netdev->flags & IFF_UP)
return -EBUSY;
args[0] = can_ch_id;
return pcan_usb_send_cmd(dev, PCAN_USB_CMD_DEVID, PCAN_USB_SET, args);
}
/*
* update current time ref with received timestamp
*/
static int pcan_usb_update_ts(struct pcan_usb_msg_context *mc)
{
if ((mc->ptr + 2) > mc->end)
return -EINVAL;
mc->ts16 = get_unaligned_le16(mc->ptr);
if (mc->rec_idx > 0)
peak_usb_update_ts_now(&mc->pdev->time_ref, mc->ts16);
else
peak_usb_set_ts_now(&mc->pdev->time_ref, mc->ts16);
return 0;
}
/*
* decode received timestamp
*/
static int pcan_usb_decode_ts(struct pcan_usb_msg_context *mc, u8 first_packet)
{
/* only 1st packet supplies a word timestamp */
if (first_packet) {
if ((mc->ptr + 2) > mc->end)
return -EINVAL;
mc->ts16 = get_unaligned_le16(mc->ptr);
mc->prev_ts8 = mc->ts16 & 0x00ff;
mc->ptr += 2;
} else {
u8 ts8;
if ((mc->ptr + 1) > mc->end)
return -EINVAL;
ts8 = *mc->ptr++;
if (ts8 < mc->prev_ts8)
mc->ts16 += 0x100;
mc->ts16 &= 0xff00;
mc->ts16 |= ts8;
mc->prev_ts8 = ts8;
}
return 0;
}
static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n,
u8 status_len)
{
struct sk_buff *skb;
struct can_frame *cf;
enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
/* ignore this error until 1st ts received */
if (n == PCAN_USB_ERROR_QOVR)
if (!mc->pdev->time_ref.tick_count)
return 0;
/* allocate an skb to store the error frame */
skb = alloc_can_err_skb(mc->netdev, &cf);
if (n & PCAN_USB_ERROR_RXQOVR) {
/* data overrun interrupt */
netdev_dbg(mc->netdev, "data overrun interrupt\n");
mc->netdev->stats.rx_over_errors++;
mc->netdev->stats.rx_errors++;
if (cf) {
cf->can_id |= CAN_ERR_CRTL;
cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
}
}
if (n & PCAN_USB_ERROR_TXQFULL)
netdev_dbg(mc->netdev, "device Tx queue full)\n");
if (n & PCAN_USB_ERROR_BUS_OFF) {
new_state = CAN_STATE_BUS_OFF;
} else if (n & PCAN_USB_ERROR_BUS_HEAVY) {
new_state = ((mc->pdev->bec.txerr >= 128) ||
(mc->pdev->bec.rxerr >= 128)) ?
CAN_STATE_ERROR_PASSIVE :
CAN_STATE_ERROR_WARNING;
} else {
new_state = CAN_STATE_ERROR_ACTIVE;
}
/* handle change of state */
if (new_state != mc->pdev->dev.can.state) {
enum can_state tx_state =
(mc->pdev->bec.txerr >= mc->pdev->bec.rxerr) ?
new_state : 0;
enum can_state rx_state =
(mc->pdev->bec.txerr <= mc->pdev->bec.rxerr) ?
new_state : 0;
can_change_state(mc->netdev, cf, tx_state, rx_state);
if (new_state == CAN_STATE_BUS_OFF) {
can_bus_off(mc->netdev);
} else if (cf && (cf->can_id & CAN_ERR_CRTL)) {
/* Supply TX/RX error counters in case of
* controller error.
*/
cf->can_id = CAN_ERR_CNT;
cf->data[6] = mc->pdev->bec.txerr;
cf->data[7] = mc->pdev->bec.rxerr;
}
}
if (!skb)
return -ENOMEM;
if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
struct skb_shared_hwtstamps *hwts = skb_hwtstamps(skb);
peak_usb_get_ts_time(&mc->pdev->time_ref, mc->ts16,
&hwts->hwtstamp);
}
netif_rx(skb);
return 0;
}
/* decode bus event usb packet: first byte contains rxerr while 2nd one contains
* txerr.
*/
static int pcan_usb_handle_bus_evt(struct pcan_usb_msg_context *mc, u8 ir)
{
struct pcan_usb *pdev = mc->pdev;
/* according to the content of the packet */
switch (ir) {
case PCAN_USB_ERR_CNT_DEC:
case PCAN_USB_ERR_CNT_INC:
/* save rx/tx error counters from in the device context */
pdev->bec.rxerr = mc->ptr[1];
pdev->bec.txerr = mc->ptr[2];
break;
default:
/* reserved */
break;
}
return 0;
}
/*
* decode non-data usb message
*/
static int pcan_usb_decode_status(struct pcan_usb_msg_context *mc,
u8 status_len)
{
u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC;
u8 f, n;
int err;
/* check whether function and number can be read */
if ((mc->ptr + 2) > mc->end)
return -EINVAL;
f = mc->ptr[PCAN_USB_CMD_FUNC];
n = mc->ptr[PCAN_USB_CMD_NUM];
mc->ptr += PCAN_USB_CMD_ARGS;
if (status_len & PCAN_USB_STATUSLEN_TIMESTAMP) {
int err = pcan_usb_decode_ts(mc, !mc->rec_ts_idx);
if (err)
return err;
/* Next packet in the buffer will have a timestamp on a single
* byte
*/
mc->rec_ts_idx++;
}
switch (f) {
case PCAN_USB_REC_ERROR:
err = pcan_usb_decode_error(mc, n, status_len);
if (err)
return err;
break;
case PCAN_USB_REC_ANALOG:
/* analog values (ignored) */
rec_len = 2;
break;
case PCAN_USB_REC_BUSLOAD:
/* bus load (ignored) */
rec_len = 1;
break;
case PCAN_USB_REC_TS:
/* only timestamp */
if (pcan_usb_update_ts(mc))
return -EINVAL;
break;
case PCAN_USB_REC_BUSEVT:
/* bus event notifications (get rxerr/txerr) */
err = pcan_usb_handle_bus_evt(mc, n);
if (err)
return err;
break;
default:
netdev_err(mc->netdev, "unexpected function %u\n", f);
break;
}
if ((mc->ptr + rec_len) > mc->end)
return -EINVAL;
mc->ptr += rec_len;
return 0;
}
/*
* decode data usb message
*/
static int pcan_usb_decode_data(struct pcan_usb_msg_context *mc, u8 status_len)
{
u8 rec_len = status_len & PCAN_USB_STATUSLEN_DLC;
struct sk_buff *skb;
struct can_frame *cf;
struct skb_shared_hwtstamps *hwts;
u32 can_id_flags;
skb = alloc_can_skb(mc->netdev, &cf);
if (!skb)
return -ENOMEM;
if (status_len & PCAN_USB_STATUSLEN_EXT_ID) {
if ((mc->ptr + 4) > mc->end)
goto decode_failed;
can_id_flags = get_unaligned_le32(mc->ptr);
cf->can_id = can_id_flags >> 3 | CAN_EFF_FLAG;
mc->ptr += 4;
} else {
if ((mc->ptr + 2) > mc->end)
goto decode_failed;
can_id_flags = get_unaligned_le16(mc->ptr);
cf->can_id = can_id_flags >> 5;
mc->ptr += 2;
}
can_frame_set_cc_len(cf, rec_len, mc->pdev->dev.can.ctrlmode);
/* Only first packet timestamp is a word */
if (pcan_usb_decode_ts(mc, !mc->rec_ts_idx))
goto decode_failed;
/* Next packet in the buffer will have a timestamp on a single byte */
mc->rec_ts_idx++;
/* read data */
memset(cf->data, 0x0, sizeof(cf->data));
if (status_len & PCAN_USB_STATUSLEN_RTR) {
cf->can_id |= CAN_RTR_FLAG;
} else {
if ((mc->ptr + rec_len) > mc->end)
goto decode_failed;
memcpy(cf->data, mc->ptr, cf->len);
mc->ptr += rec_len;
/* Ignore next byte (client private id) if SRR bit is set */
if (can_id_flags & PCAN_USB_TX_SRR)
mc->ptr++;
/* update statistics */
mc->netdev->stats.rx_bytes += cf->len;
}
mc->netdev->stats.rx_packets++;
/* convert timestamp into kernel time */
hwts = skb_hwtstamps(skb);
peak_usb_get_ts_time(&mc->pdev->time_ref, mc->ts16, &hwts->hwtstamp);
/* push the skb */
netif_rx(skb);
return 0;
decode_failed:
dev_kfree_skb(skb);
return -EINVAL;
}
/*
* process incoming message
*/
static int pcan_usb_decode_msg(struct peak_usb_device *dev, u8 *ibuf, u32 lbuf)
{
struct pcan_usb_msg_context mc = {
.rec_cnt = ibuf[1],
.ptr = ibuf + PCAN_USB_MSG_HEADER_LEN,
.end = ibuf + lbuf,
.netdev = dev->netdev,
.pdev = container_of(dev, struct pcan_usb, dev),
};
int err;
for (err = 0; mc.rec_idx < mc.rec_cnt && !err; mc.rec_idx++) {
u8 sl = *mc.ptr++;
/* handle status and error frames here */
if (sl & PCAN_USB_STATUSLEN_INTERNAL) {
err = pcan_usb_decode_status(&mc, sl);
/* handle normal can frames here */
} else {
err = pcan_usb_decode_data(&mc, sl);
}
}
return err;
}
/*
* process any incoming buffer
*/
static int pcan_usb_decode_buf(struct peak_usb_device *dev, struct urb *urb)
{
int err = 0;
if (urb->actual_length > PCAN_USB_MSG_HEADER_LEN) {
err = pcan_usb_decode_msg(dev, urb->transfer_buffer,
urb->actual_length);
} else if (urb->actual_length > 0) {
netdev_err(dev->netdev, "usb message length error (%u)\n",
urb->actual_length);
err = -EINVAL;
}
return err;
}
/*
* process outgoing packet
*/
static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb,
u8 *obuf, size_t *size)
{
struct net_device *netdev = dev->netdev;
struct net_device_stats *stats = &netdev->stats;
struct can_frame *cf = (struct can_frame *)skb->data;
u32 can_id_flags = cf->can_id & CAN_ERR_MASK;
u8 *pc;
obuf[0] = PCAN_USB_MSG_TX_CAN;
obuf[1] = 1; /* only one CAN frame is stored in the packet */
pc = obuf + PCAN_USB_MSG_HEADER_LEN;
/* status/len byte */
*pc = can_get_cc_dlc(cf, dev->can.ctrlmode);
if (cf->can_id & CAN_RTR_FLAG)
*pc |= PCAN_USB_STATUSLEN_RTR;
/* can id */
if (cf->can_id & CAN_EFF_FLAG) {
*pc |= PCAN_USB_STATUSLEN_EXT_ID;
pc++;
can_id_flags <<= 3;
if (dev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
can_id_flags |= PCAN_USB_TX_SRR;
if (dev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
can_id_flags |= PCAN_USB_TX_AT;
put_unaligned_le32(can_id_flags, pc);
pc += 4;
} else {
pc++;
can_id_flags <<= 5;
if (dev->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
can_id_flags |= PCAN_USB_TX_SRR;
if (dev->can.ctrlmode & CAN_CTRLMODE_ONE_SHOT)
can_id_flags |= PCAN_USB_TX_AT;
put_unaligned_le16(can_id_flags, pc);
pc += 2;
}
/* can data */
if (!(cf->can_id & CAN_RTR_FLAG)) {
memcpy(pc, cf->data, cf->len);
pc += cf->len;
}
/* SRR bit needs a writer id (useless here) */
if (can_id_flags & PCAN_USB_TX_SRR)
*pc++ = 0x80;
obuf[(*size)-1] = (u8)(stats->tx_packets & 0xff);
return 0;
}
/* socket callback used to copy berr counters values received through USB */
static int pcan_usb_get_berr_counter(const struct net_device *netdev,
struct can_berr_counter *bec)
{
struct peak_usb_device *dev = netdev_priv(netdev);
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
*bec = pdev->bec;
/* must return 0 */
return 0;
}
/*
* start interface
*/
static int pcan_usb_start(struct peak_usb_device *dev)
{
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
int err;
/* number of bits used in timestamps read from adapter struct */
peak_usb_init_time_ref(&pdev->time_ref, &pcan_usb);
pdev->bec.rxerr = 0;
pdev->bec.txerr = 0;
/* always ask the device for BERR reporting, to be able to switch from
* WARNING to PASSIVE state
*/
err = pcan_usb_set_err_frame(dev, PCAN_USB_BERR_MASK);
if (err)
netdev_warn(dev->netdev,
"Asking for BERR reporting error %u\n",
err);
/* if revision greater than 3, can put silent mode on/off */
if (dev->device_rev > 3) {
err = pcan_usb_set_silent(dev,
dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY);
if (err)
return err;
}
return pcan_usb_set_ext_vcc(dev, 0);
}
static int pcan_usb_init(struct peak_usb_device *dev)
{
struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev);
u32 serial_number;
int err;
/* initialize a timer needed to wait for hardware restart */
timer_setup(&pdev->restart_timer, pcan_usb_restart, 0);
/*
* explicit use of dev_xxx() instead of netdev_xxx() here:
* information displayed are related to the device itself, not
* to the canx netdevice.
*/
err = pcan_usb_get_serial(dev, &serial_number);
if (err) {
dev_err(dev->netdev->dev.parent,
"unable to read %s serial number (err %d)\n",
pcan_usb.name, err);
return err;
}
dev_info(dev->netdev->dev.parent,
"PEAK-System %s adapter hwrev %u serial %08X (%u channel)\n",
pcan_usb.name, dev->device_rev, serial_number,
pcan_usb.ctrl_count);
/* Since rev 4.1, PCAN-USB is able to make single-shot as well as
* looped back frames.
*/
if (dev->device_rev >= 41) {
struct can_priv *priv = netdev_priv(dev->netdev);
priv->ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT |
CAN_CTRLMODE_LOOPBACK;
} else {
dev_info(dev->netdev->dev.parent,
"Firmware update available. Please contact support@peak-system.com\n");
}
return 0;
}
/*
* probe function for new PCAN-USB usb interface
*/
static int pcan_usb_probe(struct usb_interface *intf)
{
struct usb_host_interface *if_desc;
int i;
if_desc = intf->altsetting;
/* check interface endpoint addresses */
for (i = 0; i < if_desc->desc.bNumEndpoints; i++) {
struct usb_endpoint_descriptor *ep = &if_desc->endpoint[i].desc;
switch (ep->bEndpointAddress) {
case PCAN_USB_EP_CMDOUT:
case PCAN_USB_EP_CMDIN:
case PCAN_USB_EP_MSGOUT:
case PCAN_USB_EP_MSGIN:
break;
default:
return -ENODEV;
}
}
return 0;
}
static int pcan_usb_set_phys_id(struct net_device *netdev,
enum ethtool_phys_id_state state)
{
struct peak_usb_device *dev = netdev_priv(netdev);
int err = 0;
switch (state) {
case ETHTOOL_ID_ACTIVE:
/* call ON/OFF twice a second */
return 2;
case ETHTOOL_ID_OFF:
err = pcan_usb_set_led(dev, 0);
break;
case ETHTOOL_ID_ON:
fallthrough;
case ETHTOOL_ID_INACTIVE:
/* restore LED default */
err = pcan_usb_set_led(dev, 1);
break;
default:
break;
}
return err;
}
/* This device only handles 8-bit CAN channel id. */
static int pcan_usb_get_eeprom_len(struct net_device *netdev)
{
return sizeof(u8);
}
static const struct ethtool_ops pcan_usb_ethtool_ops = {
.set_phys_id = pcan_usb_set_phys_id,
.get_ts_info = pcan_get_ts_info,
.get_eeprom_len = pcan_usb_get_eeprom_len,
.get_eeprom = peak_usb_get_eeprom,
.set_eeprom = peak_usb_set_eeprom,
};
/*
* describe the PCAN-USB adapter
*/
static const struct can_bittiming_const pcan_usb_const = {
.name = "pcan_usb",
.tseg1_min = 1,
.tseg1_max = 16,
.tseg2_min = 1,
.tseg2_max = 8,
.sjw_max = 4,
.brp_min = 1,
.brp_max = 64,
.brp_inc = 1,
};
const struct peak_usb_adapter pcan_usb = {
.name = "PCAN-USB",
.device_id = PCAN_USB_PRODUCT_ID,
.ctrl_count = 1,
.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY |
CAN_CTRLMODE_CC_LEN8_DLC,
.clock = {
.freq = PCAN_USB_CRYSTAL_HZ / 2,
},
.bittiming_const = &pcan_usb_const,
/* size of device private data */
.sizeof_dev_private = sizeof(struct pcan_usb),
.ethtool_ops = &pcan_usb_ethtool_ops,
/* timestamps usage */
.ts_used_bits = 16,
.us_per_ts_scale = PCAN_USB_TS_US_PER_TICK, /* us=(ts*scale) */
.us_per_ts_shift = PCAN_USB_TS_DIV_SHIFTER, /* >> shift */
/* give here messages in/out endpoints */
.ep_msg_in = PCAN_USB_EP_MSGIN,
.ep_msg_out = {PCAN_USB_EP_MSGOUT},
/* size of rx/tx usb buffers */
.rx_buffer_size = PCAN_USB_RX_BUFFER_SIZE,
.tx_buffer_size = PCAN_USB_TX_BUFFER_SIZE,
/* device callbacks */
.intf_probe = pcan_usb_probe,
.dev_init = pcan_usb_init,
.dev_set_bus = pcan_usb_write_mode,
.dev_set_bittiming = pcan_usb_set_bittiming,
.dev_get_can_channel_id = pcan_usb_get_can_channel_id,
.dev_set_can_channel_id = pcan_usb_set_can_channel_id,
.dev_decode_buf = pcan_usb_decode_buf,
.dev_encode_msg = pcan_usb_encode_msg,
.dev_start = pcan_usb_start,
.dev_restart_async = pcan_usb_restart_async,
.do_get_berr_counter = pcan_usb_get_berr_counter,
};
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