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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-08 04:21:33 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-08 04:21:33 +0000
commit282c335ad1bf4d21fcedff132e19995c24c09adc (patch)
treed24dc7bfbb3a6b4bfd5b46964347ada86f72d751 /drivers/net/can/dev.c
parentAdding upstream version 4.19.289. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 4.19.304.upstream/4.19.304upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/can/dev.c')
-rw-r--r--drivers/net/can/dev.c1324
1 files changed, 0 insertions, 1324 deletions
diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
deleted file mode 100644
index 8738d37f7..000000000
--- a/drivers/net/can/dev.c
+++ /dev/null
@@ -1,1324 +0,0 @@
-/*
- * Copyright (C) 2005 Marc Kleine-Budde, Pengutronix
- * Copyright (C) 2006 Andrey Volkov, Varma Electronics
- * Copyright (C) 2008-2009 Wolfgang Grandegger <wg@grandegger.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the version 2 of the GNU General Public License
- * as published by the Free Software Foundation
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/netdevice.h>
-#include <linux/if_arp.h>
-#include <linux/workqueue.h>
-#include <linux/can.h>
-#include <linux/can/dev.h>
-#include <linux/can/skb.h>
-#include <linux/can/netlink.h>
-#include <linux/can/led.h>
-#include <linux/of.h>
-#include <net/rtnetlink.h>
-
-#define MOD_DESC "CAN device driver interface"
-
-MODULE_DESCRIPTION(MOD_DESC);
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Wolfgang Grandegger <wg@grandegger.com>");
-
-/* CAN DLC to real data length conversion helpers */
-
-static const u8 dlc2len[] = {0, 1, 2, 3, 4, 5, 6, 7,
- 8, 12, 16, 20, 24, 32, 48, 64};
-
-/* get data length from can_dlc with sanitized can_dlc */
-u8 can_dlc2len(u8 can_dlc)
-{
- return dlc2len[can_dlc & 0x0F];
-}
-EXPORT_SYMBOL_GPL(can_dlc2len);
-
-static const u8 len2dlc[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, /* 0 - 8 */
- 9, 9, 9, 9, /* 9 - 12 */
- 10, 10, 10, 10, /* 13 - 16 */
- 11, 11, 11, 11, /* 17 - 20 */
- 12, 12, 12, 12, /* 21 - 24 */
- 13, 13, 13, 13, 13, 13, 13, 13, /* 25 - 32 */
- 14, 14, 14, 14, 14, 14, 14, 14, /* 33 - 40 */
- 14, 14, 14, 14, 14, 14, 14, 14, /* 41 - 48 */
- 15, 15, 15, 15, 15, 15, 15, 15, /* 49 - 56 */
- 15, 15, 15, 15, 15, 15, 15, 15}; /* 57 - 64 */
-
-/* map the sanitized data length to an appropriate data length code */
-u8 can_len2dlc(u8 len)
-{
- if (unlikely(len > 64))
- return 0xF;
-
- return len2dlc[len];
-}
-EXPORT_SYMBOL_GPL(can_len2dlc);
-
-#ifdef CONFIG_CAN_CALC_BITTIMING
-#define CAN_CALC_MAX_ERROR 50 /* in one-tenth of a percent */
-#define CAN_CALC_SYNC_SEG 1
-
-/*
- * Bit-timing calculation derived from:
- *
- * Code based on LinCAN sources and H8S2638 project
- * Copyright 2004-2006 Pavel Pisa - DCE FELK CVUT cz
- * Copyright 2005 Stanislav Marek
- * email: pisa@cmp.felk.cvut.cz
- *
- * Calculates proper bit-timing parameters for a specified bit-rate
- * and sample-point, which can then be used to set the bit-timing
- * registers of the CAN controller. You can find more information
- * in the header file linux/can/netlink.h.
- */
-static int can_update_sample_point(const struct can_bittiming_const *btc,
- unsigned int sample_point_nominal, unsigned int tseg,
- unsigned int *tseg1_ptr, unsigned int *tseg2_ptr,
- unsigned int *sample_point_error_ptr)
-{
- unsigned int sample_point_error, best_sample_point_error = UINT_MAX;
- unsigned int sample_point, best_sample_point = 0;
- unsigned int tseg1, tseg2;
- int i;
-
- for (i = 0; i <= 1; i++) {
- tseg2 = tseg + CAN_CALC_SYNC_SEG - (sample_point_nominal * (tseg + CAN_CALC_SYNC_SEG)) / 1000 - i;
- tseg2 = clamp(tseg2, btc->tseg2_min, btc->tseg2_max);
- tseg1 = tseg - tseg2;
- if (tseg1 > btc->tseg1_max) {
- tseg1 = btc->tseg1_max;
- tseg2 = tseg - tseg1;
- }
-
- sample_point = 1000 * (tseg + CAN_CALC_SYNC_SEG - tseg2) / (tseg + CAN_CALC_SYNC_SEG);
- sample_point_error = abs(sample_point_nominal - sample_point);
-
- if ((sample_point <= sample_point_nominal) && (sample_point_error < best_sample_point_error)) {
- best_sample_point = sample_point;
- best_sample_point_error = sample_point_error;
- *tseg1_ptr = tseg1;
- *tseg2_ptr = tseg2;
- }
- }
-
- if (sample_point_error_ptr)
- *sample_point_error_ptr = best_sample_point_error;
-
- return best_sample_point;
-}
-
-static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
- const struct can_bittiming_const *btc)
-{
- struct can_priv *priv = netdev_priv(dev);
- unsigned int bitrate; /* current bitrate */
- unsigned int bitrate_error; /* difference between current and nominal value */
- unsigned int best_bitrate_error = UINT_MAX;
- unsigned int sample_point_error; /* difference between current and nominal value */
- unsigned int best_sample_point_error = UINT_MAX;
- unsigned int sample_point_nominal; /* nominal sample point */
- unsigned int best_tseg = 0; /* current best value for tseg */
- unsigned int best_brp = 0; /* current best value for brp */
- unsigned int brp, tsegall, tseg, tseg1 = 0, tseg2 = 0;
- u64 v64;
-
- /* Use CiA recommended sample points */
- if (bt->sample_point) {
- sample_point_nominal = bt->sample_point;
- } else {
- if (bt->bitrate > 800000)
- sample_point_nominal = 750;
- else if (bt->bitrate > 500000)
- sample_point_nominal = 800;
- else
- sample_point_nominal = 875;
- }
-
- /* tseg even = round down, odd = round up */
- for (tseg = (btc->tseg1_max + btc->tseg2_max) * 2 + 1;
- tseg >= (btc->tseg1_min + btc->tseg2_min) * 2; tseg--) {
- tsegall = CAN_CALC_SYNC_SEG + tseg / 2;
-
- /* Compute all possible tseg choices (tseg=tseg1+tseg2) */
- brp = priv->clock.freq / (tsegall * bt->bitrate) + tseg % 2;
-
- /* choose brp step which is possible in system */
- brp = (brp / btc->brp_inc) * btc->brp_inc;
- if ((brp < btc->brp_min) || (brp > btc->brp_max))
- continue;
-
- bitrate = priv->clock.freq / (brp * tsegall);
- bitrate_error = abs(bt->bitrate - bitrate);
-
- /* tseg brp biterror */
- if (bitrate_error > best_bitrate_error)
- continue;
-
- /* reset sample point error if we have a better bitrate */
- if (bitrate_error < best_bitrate_error)
- best_sample_point_error = UINT_MAX;
-
- can_update_sample_point(btc, sample_point_nominal, tseg / 2, &tseg1, &tseg2, &sample_point_error);
- if (sample_point_error > best_sample_point_error)
- continue;
-
- best_sample_point_error = sample_point_error;
- best_bitrate_error = bitrate_error;
- best_tseg = tseg / 2;
- best_brp = brp;
-
- if (bitrate_error == 0 && sample_point_error == 0)
- break;
- }
-
- if (best_bitrate_error) {
- /* Error in one-tenth of a percent */
- v64 = (u64)best_bitrate_error * 1000;
- do_div(v64, bt->bitrate);
- bitrate_error = (u32)v64;
- if (bitrate_error > CAN_CALC_MAX_ERROR) {
- netdev_err(dev,
- "bitrate error %d.%d%% too high\n",
- bitrate_error / 10, bitrate_error % 10);
- return -EDOM;
- }
- netdev_warn(dev, "bitrate error %d.%d%%\n",
- bitrate_error / 10, bitrate_error % 10);
- }
-
- /* real sample point */
- bt->sample_point = can_update_sample_point(btc, sample_point_nominal, best_tseg,
- &tseg1, &tseg2, NULL);
-
- v64 = (u64)best_brp * 1000 * 1000 * 1000;
- do_div(v64, priv->clock.freq);
- bt->tq = (u32)v64;
- bt->prop_seg = tseg1 / 2;
- bt->phase_seg1 = tseg1 - bt->prop_seg;
- bt->phase_seg2 = tseg2;
-
- /* check for sjw user settings */
- if (!bt->sjw || !btc->sjw_max) {
- bt->sjw = 1;
- } else {
- /* bt->sjw is at least 1 -> sanitize upper bound to sjw_max */
- if (bt->sjw > btc->sjw_max)
- bt->sjw = btc->sjw_max;
- /* bt->sjw must not be higher than tseg2 */
- if (tseg2 < bt->sjw)
- bt->sjw = tseg2;
- }
-
- bt->brp = best_brp;
-
- /* real bitrate */
- bt->bitrate = priv->clock.freq / (bt->brp * (CAN_CALC_SYNC_SEG + tseg1 + tseg2));
-
- return 0;
-}
-#else /* !CONFIG_CAN_CALC_BITTIMING */
-static int can_calc_bittiming(struct net_device *dev, struct can_bittiming *bt,
- const struct can_bittiming_const *btc)
-{
- netdev_err(dev, "bit-timing calculation not available\n");
- return -EINVAL;
-}
-#endif /* CONFIG_CAN_CALC_BITTIMING */
-
-/*
- * Checks the validity of the specified bit-timing parameters prop_seg,
- * phase_seg1, phase_seg2 and sjw and tries to determine the bitrate
- * prescaler value brp. You can find more information in the header
- * file linux/can/netlink.h.
- */
-static int can_fixup_bittiming(struct net_device *dev, struct can_bittiming *bt,
- const struct can_bittiming_const *btc)
-{
- struct can_priv *priv = netdev_priv(dev);
- int tseg1, alltseg;
- u64 brp64;
-
- tseg1 = bt->prop_seg + bt->phase_seg1;
- if (!bt->sjw)
- bt->sjw = 1;
- if (bt->sjw > btc->sjw_max ||
- tseg1 < btc->tseg1_min || tseg1 > btc->tseg1_max ||
- bt->phase_seg2 < btc->tseg2_min || bt->phase_seg2 > btc->tseg2_max)
- return -ERANGE;
-
- brp64 = (u64)priv->clock.freq * (u64)bt->tq;
- if (btc->brp_inc > 1)
- do_div(brp64, btc->brp_inc);
- brp64 += 500000000UL - 1;
- do_div(brp64, 1000000000UL); /* the practicable BRP */
- if (btc->brp_inc > 1)
- brp64 *= btc->brp_inc;
- bt->brp = (u32)brp64;
-
- if (bt->brp < btc->brp_min || bt->brp > btc->brp_max)
- return -EINVAL;
-
- alltseg = bt->prop_seg + bt->phase_seg1 + bt->phase_seg2 + 1;
- bt->bitrate = priv->clock.freq / (bt->brp * alltseg);
- bt->sample_point = ((tseg1 + 1) * 1000) / alltseg;
-
- return 0;
-}
-
-/* Checks the validity of predefined bitrate settings */
-static int can_validate_bitrate(struct net_device *dev, struct can_bittiming *bt,
- const u32 *bitrate_const,
- const unsigned int bitrate_const_cnt)
-{
- struct can_priv *priv = netdev_priv(dev);
- unsigned int i;
-
- for (i = 0; i < bitrate_const_cnt; i++) {
- if (bt->bitrate == bitrate_const[i])
- break;
- }
-
- if (i >= priv->bitrate_const_cnt)
- return -EINVAL;
-
- return 0;
-}
-
-static int can_get_bittiming(struct net_device *dev, struct can_bittiming *bt,
- const struct can_bittiming_const *btc,
- const u32 *bitrate_const,
- const unsigned int bitrate_const_cnt)
-{
- int err;
-
- /*
- * Depending on the given can_bittiming parameter structure the CAN
- * timing parameters are calculated based on the provided bitrate OR
- * alternatively the CAN timing parameters (tq, prop_seg, etc.) are
- * provided directly which are then checked and fixed up.
- */
- if (!bt->tq && bt->bitrate && btc)
- err = can_calc_bittiming(dev, bt, btc);
- else if (bt->tq && !bt->bitrate && btc)
- err = can_fixup_bittiming(dev, bt, btc);
- else if (!bt->tq && bt->bitrate && bitrate_const)
- err = can_validate_bitrate(dev, bt, bitrate_const,
- bitrate_const_cnt);
- else
- err = -EINVAL;
-
- return err;
-}
-
-static void can_update_state_error_stats(struct net_device *dev,
- enum can_state new_state)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- if (new_state <= priv->state)
- return;
-
- switch (new_state) {
- case CAN_STATE_ERROR_WARNING:
- priv->can_stats.error_warning++;
- break;
- case CAN_STATE_ERROR_PASSIVE:
- priv->can_stats.error_passive++;
- break;
- case CAN_STATE_BUS_OFF:
- priv->can_stats.bus_off++;
- break;
- default:
- break;
- }
-}
-
-static int can_tx_state_to_frame(struct net_device *dev, enum can_state state)
-{
- switch (state) {
- case CAN_STATE_ERROR_ACTIVE:
- return CAN_ERR_CRTL_ACTIVE;
- case CAN_STATE_ERROR_WARNING:
- return CAN_ERR_CRTL_TX_WARNING;
- case CAN_STATE_ERROR_PASSIVE:
- return CAN_ERR_CRTL_TX_PASSIVE;
- default:
- return 0;
- }
-}
-
-static int can_rx_state_to_frame(struct net_device *dev, enum can_state state)
-{
- switch (state) {
- case CAN_STATE_ERROR_ACTIVE:
- return CAN_ERR_CRTL_ACTIVE;
- case CAN_STATE_ERROR_WARNING:
- return CAN_ERR_CRTL_RX_WARNING;
- case CAN_STATE_ERROR_PASSIVE:
- return CAN_ERR_CRTL_RX_PASSIVE;
- default:
- return 0;
- }
-}
-
-void can_change_state(struct net_device *dev, struct can_frame *cf,
- enum can_state tx_state, enum can_state rx_state)
-{
- struct can_priv *priv = netdev_priv(dev);
- enum can_state new_state = max(tx_state, rx_state);
-
- if (unlikely(new_state == priv->state)) {
- netdev_warn(dev, "%s: oops, state did not change", __func__);
- return;
- }
-
- netdev_dbg(dev, "New error state: %d\n", new_state);
-
- can_update_state_error_stats(dev, new_state);
- priv->state = new_state;
-
- if (!cf)
- return;
-
- if (unlikely(new_state == CAN_STATE_BUS_OFF)) {
- cf->can_id |= CAN_ERR_BUSOFF;
- return;
- }
-
- cf->can_id |= CAN_ERR_CRTL;
- cf->data[1] |= tx_state >= rx_state ?
- can_tx_state_to_frame(dev, tx_state) : 0;
- cf->data[1] |= tx_state <= rx_state ?
- can_rx_state_to_frame(dev, rx_state) : 0;
-}
-EXPORT_SYMBOL_GPL(can_change_state);
-
-/*
- * Local echo of CAN messages
- *
- * CAN network devices *should* support a local echo functionality
- * (see Documentation/networking/can.rst). To test the handling of CAN
- * interfaces that do not support the local echo both driver types are
- * implemented. In the case that the driver does not support the echo
- * the IFF_ECHO remains clear in dev->flags. This causes the PF_CAN core
- * to perform the echo as a fallback solution.
- */
-static void can_flush_echo_skb(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
- struct net_device_stats *stats = &dev->stats;
- int i;
-
- for (i = 0; i < priv->echo_skb_max; i++) {
- if (priv->echo_skb[i]) {
- kfree_skb(priv->echo_skb[i]);
- priv->echo_skb[i] = NULL;
- stats->tx_dropped++;
- stats->tx_aborted_errors++;
- }
- }
-}
-
-/*
- * Put the skb on the stack to be looped backed locally lateron
- *
- * The function is typically called in the start_xmit function
- * of the device driver. The driver must protect access to
- * priv->echo_skb, if necessary.
- */
-void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
- unsigned int idx)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- BUG_ON(idx >= priv->echo_skb_max);
-
- /* check flag whether this packet has to be looped back */
- if (!(dev->flags & IFF_ECHO) || skb->pkt_type != PACKET_LOOPBACK ||
- (skb->protocol != htons(ETH_P_CAN) &&
- skb->protocol != htons(ETH_P_CANFD))) {
- kfree_skb(skb);
- return;
- }
-
- if (!priv->echo_skb[idx]) {
-
- skb = can_create_echo_skb(skb);
- if (!skb)
- return;
-
- /* make settings for echo to reduce code in irq context */
- skb->pkt_type = PACKET_BROADCAST;
- skb->ip_summed = CHECKSUM_UNNECESSARY;
- skb->dev = dev;
-
- /* save this skb for tx interrupt echo handling */
- priv->echo_skb[idx] = skb;
- } else {
- /* locking problem with netif_stop_queue() ?? */
- netdev_err(dev, "%s: BUG! echo_skb is occupied!\n", __func__);
- kfree_skb(skb);
- }
-}
-EXPORT_SYMBOL_GPL(can_put_echo_skb);
-
-struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx, u8 *len_ptr)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- if (idx >= priv->echo_skb_max) {
- netdev_err(dev, "%s: BUG! Trying to access can_priv::echo_skb out of bounds (%u/max %u)\n",
- __func__, idx, priv->echo_skb_max);
- return NULL;
- }
-
- if (priv->echo_skb[idx]) {
- /* Using "struct canfd_frame::len" for the frame
- * length is supported on both CAN and CANFD frames.
- */
- struct sk_buff *skb = priv->echo_skb[idx];
- struct canfd_frame *cf = (struct canfd_frame *)skb->data;
-
- /* get the real payload length for netdev statistics */
- if (cf->can_id & CAN_RTR_FLAG)
- *len_ptr = 0;
- else
- *len_ptr = cf->len;
-
- priv->echo_skb[idx] = NULL;
-
- return skb;
- }
-
- return NULL;
-}
-
-/*
- * Get the skb from the stack and loop it back locally
- *
- * The function is typically called when the TX done interrupt
- * is handled in the device driver. The driver must protect
- * access to priv->echo_skb, if necessary.
- */
-unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx)
-{
- struct sk_buff *skb;
- u8 len;
-
- skb = __can_get_echo_skb(dev, idx, &len);
- if (!skb)
- return 0;
-
- skb_get(skb);
- if (netif_rx(skb) == NET_RX_SUCCESS)
- dev_consume_skb_any(skb);
- else
- dev_kfree_skb_any(skb);
-
- return len;
-}
-EXPORT_SYMBOL_GPL(can_get_echo_skb);
-
-/*
- * Remove the skb from the stack and free it.
- *
- * The function is typically called when TX failed.
- */
-void can_free_echo_skb(struct net_device *dev, unsigned int idx)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- BUG_ON(idx >= priv->echo_skb_max);
-
- if (priv->echo_skb[idx]) {
- dev_kfree_skb_any(priv->echo_skb[idx]);
- priv->echo_skb[idx] = NULL;
- }
-}
-EXPORT_SYMBOL_GPL(can_free_echo_skb);
-
-/*
- * CAN device restart for bus-off recovery
- */
-static void can_restart(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
- struct net_device_stats *stats = &dev->stats;
- struct sk_buff *skb;
- struct can_frame *cf;
- int err;
-
- BUG_ON(netif_carrier_ok(dev));
-
- /*
- * No synchronization needed because the device is bus-off and
- * no messages can come in or go out.
- */
- can_flush_echo_skb(dev);
-
- /* send restart message upstream */
- skb = alloc_can_err_skb(dev, &cf);
- if (skb == NULL) {
- err = -ENOMEM;
- goto restart;
- }
- cf->can_id |= CAN_ERR_RESTARTED;
-
- stats->rx_packets++;
- stats->rx_bytes += cf->can_dlc;
-
- netif_rx_ni(skb);
-
-restart:
- netdev_dbg(dev, "restarted\n");
- priv->can_stats.restarts++;
-
- /* Now restart the device */
- err = priv->do_set_mode(dev, CAN_MODE_START);
-
- netif_carrier_on(dev);
- if (err)
- netdev_err(dev, "Error %d during restart", err);
-}
-
-static void can_restart_work(struct work_struct *work)
-{
- struct delayed_work *dwork = to_delayed_work(work);
- struct can_priv *priv = container_of(dwork, struct can_priv, restart_work);
-
- can_restart(priv->dev);
-}
-
-int can_restart_now(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- /*
- * A manual restart is only permitted if automatic restart is
- * disabled and the device is in the bus-off state
- */
- if (priv->restart_ms)
- return -EINVAL;
- if (priv->state != CAN_STATE_BUS_OFF)
- return -EBUSY;
-
- cancel_delayed_work_sync(&priv->restart_work);
- can_restart(dev);
-
- return 0;
-}
-
-/*
- * CAN bus-off
- *
- * This functions should be called when the device goes bus-off to
- * tell the netif layer that no more packets can be sent or received.
- * If enabled, a timer is started to trigger bus-off recovery.
- */
-void can_bus_off(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- netdev_info(dev, "bus-off\n");
-
- netif_carrier_off(dev);
-
- if (priv->restart_ms)
- schedule_delayed_work(&priv->restart_work,
- msecs_to_jiffies(priv->restart_ms));
-}
-EXPORT_SYMBOL_GPL(can_bus_off);
-
-static void can_setup(struct net_device *dev)
-{
- dev->type = ARPHRD_CAN;
- dev->mtu = CAN_MTU;
- dev->hard_header_len = 0;
- dev->addr_len = 0;
- dev->tx_queue_len = 10;
-
- /* New-style flags. */
- dev->flags = IFF_NOARP;
- dev->features = NETIF_F_HW_CSUM;
-}
-
-struct sk_buff *alloc_can_skb(struct net_device *dev, struct can_frame **cf)
-{
- struct sk_buff *skb;
-
- skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
- sizeof(struct can_frame));
- if (unlikely(!skb))
- return NULL;
-
- skb->protocol = htons(ETH_P_CAN);
- skb->pkt_type = PACKET_BROADCAST;
- skb->ip_summed = CHECKSUM_UNNECESSARY;
-
- skb_reset_mac_header(skb);
- skb_reset_network_header(skb);
- skb_reset_transport_header(skb);
-
- can_skb_reserve(skb);
- can_skb_prv(skb)->ifindex = dev->ifindex;
- can_skb_prv(skb)->skbcnt = 0;
-
- *cf = skb_put_zero(skb, sizeof(struct can_frame));
-
- return skb;
-}
-EXPORT_SYMBOL_GPL(alloc_can_skb);
-
-struct sk_buff *alloc_canfd_skb(struct net_device *dev,
- struct canfd_frame **cfd)
-{
- struct sk_buff *skb;
-
- skb = netdev_alloc_skb(dev, sizeof(struct can_skb_priv) +
- sizeof(struct canfd_frame));
- if (unlikely(!skb))
- return NULL;
-
- skb->protocol = htons(ETH_P_CANFD);
- skb->pkt_type = PACKET_BROADCAST;
- skb->ip_summed = CHECKSUM_UNNECESSARY;
-
- skb_reset_mac_header(skb);
- skb_reset_network_header(skb);
- skb_reset_transport_header(skb);
-
- can_skb_reserve(skb);
- can_skb_prv(skb)->ifindex = dev->ifindex;
- can_skb_prv(skb)->skbcnt = 0;
-
- *cfd = skb_put_zero(skb, sizeof(struct canfd_frame));
-
- return skb;
-}
-EXPORT_SYMBOL_GPL(alloc_canfd_skb);
-
-struct sk_buff *alloc_can_err_skb(struct net_device *dev, struct can_frame **cf)
-{
- struct sk_buff *skb;
-
- skb = alloc_can_skb(dev, cf);
- if (unlikely(!skb))
- return NULL;
-
- (*cf)->can_id = CAN_ERR_FLAG;
- (*cf)->can_dlc = CAN_ERR_DLC;
-
- return skb;
-}
-EXPORT_SYMBOL_GPL(alloc_can_err_skb);
-
-/*
- * Allocate and setup space for the CAN network device
- */
-struct net_device *alloc_candev_mqs(int sizeof_priv, unsigned int echo_skb_max,
- unsigned int txqs, unsigned int rxqs)
-{
- struct net_device *dev;
- struct can_priv *priv;
- int size;
-
- if (echo_skb_max)
- size = ALIGN(sizeof_priv, sizeof(struct sk_buff *)) +
- echo_skb_max * sizeof(struct sk_buff *);
- else
- size = sizeof_priv;
-
- dev = alloc_netdev_mqs(size, "can%d", NET_NAME_UNKNOWN, can_setup,
- txqs, rxqs);
- if (!dev)
- return NULL;
-
- priv = netdev_priv(dev);
- priv->dev = dev;
-
- if (echo_skb_max) {
- priv->echo_skb_max = echo_skb_max;
- priv->echo_skb = (void *)priv +
- ALIGN(sizeof_priv, sizeof(struct sk_buff *));
- }
-
- priv->state = CAN_STATE_STOPPED;
-
- INIT_DELAYED_WORK(&priv->restart_work, can_restart_work);
-
- return dev;
-}
-EXPORT_SYMBOL_GPL(alloc_candev_mqs);
-
-/*
- * Free space of the CAN network device
- */
-void free_candev(struct net_device *dev)
-{
- free_netdev(dev);
-}
-EXPORT_SYMBOL_GPL(free_candev);
-
-/*
- * changing MTU and control mode for CAN/CANFD devices
- */
-int can_change_mtu(struct net_device *dev, int new_mtu)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- /* Do not allow changing the MTU while running */
- if (dev->flags & IFF_UP)
- return -EBUSY;
-
- /* allow change of MTU according to the CANFD ability of the device */
- switch (new_mtu) {
- case CAN_MTU:
- /* 'CANFD-only' controllers can not switch to CAN_MTU */
- if (priv->ctrlmode_static & CAN_CTRLMODE_FD)
- return -EINVAL;
-
- priv->ctrlmode &= ~CAN_CTRLMODE_FD;
- break;
-
- case CANFD_MTU:
- /* check for potential CANFD ability */
- if (!(priv->ctrlmode_supported & CAN_CTRLMODE_FD) &&
- !(priv->ctrlmode_static & CAN_CTRLMODE_FD))
- return -EINVAL;
-
- priv->ctrlmode |= CAN_CTRLMODE_FD;
- break;
-
- default:
- return -EINVAL;
- }
-
- dev->mtu = new_mtu;
- return 0;
-}
-EXPORT_SYMBOL_GPL(can_change_mtu);
-
-/*
- * Common open function when the device gets opened.
- *
- * This function should be called in the open function of the device
- * driver.
- */
-int open_candev(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- if (!priv->bittiming.bitrate) {
- netdev_err(dev, "bit-timing not yet defined\n");
- return -EINVAL;
- }
-
- /* For CAN FD the data bitrate has to be >= the arbitration bitrate */
- if ((priv->ctrlmode & CAN_CTRLMODE_FD) &&
- (!priv->data_bittiming.bitrate ||
- (priv->data_bittiming.bitrate < priv->bittiming.bitrate))) {
- netdev_err(dev, "incorrect/missing data bit-timing\n");
- return -EINVAL;
- }
-
- /* Switch carrier on if device was stopped while in bus-off state */
- if (!netif_carrier_ok(dev))
- netif_carrier_on(dev);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(open_candev);
-
-#ifdef CONFIG_OF
-/* Common function that can be used to understand the limitation of
- * a transceiver when it provides no means to determine these limitations
- * at runtime.
- */
-void of_can_transceiver(struct net_device *dev)
-{
- struct device_node *dn;
- struct can_priv *priv = netdev_priv(dev);
- struct device_node *np = dev->dev.parent->of_node;
- int ret;
-
- dn = of_get_child_by_name(np, "can-transceiver");
- if (!dn)
- return;
-
- ret = of_property_read_u32(dn, "max-bitrate", &priv->bitrate_max);
- of_node_put(dn);
- if ((ret && ret != -EINVAL) || (!ret && !priv->bitrate_max))
- netdev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit.\n");
-}
-EXPORT_SYMBOL_GPL(of_can_transceiver);
-#endif
-
-/*
- * Common close function for cleanup before the device gets closed.
- *
- * This function should be called in the close function of the device
- * driver.
- */
-void close_candev(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- cancel_delayed_work_sync(&priv->restart_work);
- can_flush_echo_skb(dev);
-}
-EXPORT_SYMBOL_GPL(close_candev);
-
-/*
- * CAN netlink interface
- */
-static const struct nla_policy can_policy[IFLA_CAN_MAX + 1] = {
- [IFLA_CAN_STATE] = { .type = NLA_U32 },
- [IFLA_CAN_CTRLMODE] = { .len = sizeof(struct can_ctrlmode) },
- [IFLA_CAN_RESTART_MS] = { .type = NLA_U32 },
- [IFLA_CAN_RESTART] = { .type = NLA_U32 },
- [IFLA_CAN_BITTIMING] = { .len = sizeof(struct can_bittiming) },
- [IFLA_CAN_BITTIMING_CONST]
- = { .len = sizeof(struct can_bittiming_const) },
- [IFLA_CAN_CLOCK] = { .len = sizeof(struct can_clock) },
- [IFLA_CAN_BERR_COUNTER] = { .len = sizeof(struct can_berr_counter) },
- [IFLA_CAN_DATA_BITTIMING]
- = { .len = sizeof(struct can_bittiming) },
- [IFLA_CAN_DATA_BITTIMING_CONST]
- = { .len = sizeof(struct can_bittiming_const) },
- [IFLA_CAN_TERMINATION] = { .type = NLA_U16 },
-};
-
-static int can_validate(struct nlattr *tb[], struct nlattr *data[],
- struct netlink_ext_ack *extack)
-{
- bool is_can_fd = false;
-
- /* Make sure that valid CAN FD configurations always consist of
- * - nominal/arbitration bittiming
- * - data bittiming
- * - control mode with CAN_CTRLMODE_FD set
- */
-
- if (!data)
- return 0;
-
- if (data[IFLA_CAN_CTRLMODE]) {
- struct can_ctrlmode *cm = nla_data(data[IFLA_CAN_CTRLMODE]);
-
- is_can_fd = cm->flags & cm->mask & CAN_CTRLMODE_FD;
- }
-
- if (is_can_fd) {
- if (!data[IFLA_CAN_BITTIMING] || !data[IFLA_CAN_DATA_BITTIMING])
- return -EOPNOTSUPP;
- }
-
- if (data[IFLA_CAN_DATA_BITTIMING]) {
- if (!is_can_fd || !data[IFLA_CAN_BITTIMING])
- return -EOPNOTSUPP;
- }
-
- return 0;
-}
-
-static int can_changelink(struct net_device *dev, struct nlattr *tb[],
- struct nlattr *data[],
- struct netlink_ext_ack *extack)
-{
- struct can_priv *priv = netdev_priv(dev);
- int err;
-
- /* We need synchronization with dev->stop() */
- ASSERT_RTNL();
-
- if (data[IFLA_CAN_BITTIMING]) {
- struct can_bittiming bt;
-
- /* Do not allow changing bittiming while running */
- if (dev->flags & IFF_UP)
- return -EBUSY;
-
- /* Calculate bittiming parameters based on
- * bittiming_const if set, otherwise pass bitrate
- * directly via do_set_bitrate(). Bail out if neither
- * is given.
- */
- if (!priv->bittiming_const && !priv->do_set_bittiming)
- return -EOPNOTSUPP;
-
- memcpy(&bt, nla_data(data[IFLA_CAN_BITTIMING]), sizeof(bt));
- err = can_get_bittiming(dev, &bt,
- priv->bittiming_const,
- priv->bitrate_const,
- priv->bitrate_const_cnt);
- if (err)
- return err;
-
- if (priv->bitrate_max && bt.bitrate > priv->bitrate_max) {
- netdev_err(dev, "arbitration bitrate surpasses transceiver capabilities of %d bps\n",
- priv->bitrate_max);
- return -EINVAL;
- }
-
- memcpy(&priv->bittiming, &bt, sizeof(bt));
-
- if (priv->do_set_bittiming) {
- /* Finally, set the bit-timing registers */
- err = priv->do_set_bittiming(dev);
- if (err)
- return err;
- }
- }
-
- if (data[IFLA_CAN_CTRLMODE]) {
- struct can_ctrlmode *cm;
- u32 ctrlstatic;
- u32 maskedflags;
-
- /* Do not allow changing controller mode while running */
- if (dev->flags & IFF_UP)
- return -EBUSY;
- cm = nla_data(data[IFLA_CAN_CTRLMODE]);
- ctrlstatic = priv->ctrlmode_static;
- maskedflags = cm->flags & cm->mask;
-
- /* check whether provided bits are allowed to be passed */
- if (cm->mask & ~(priv->ctrlmode_supported | ctrlstatic))
- return -EOPNOTSUPP;
-
- /* do not check for static fd-non-iso if 'fd' is disabled */
- if (!(maskedflags & CAN_CTRLMODE_FD))
- ctrlstatic &= ~CAN_CTRLMODE_FD_NON_ISO;
-
- /* make sure static options are provided by configuration */
- if ((maskedflags & ctrlstatic) != ctrlstatic)
- return -EOPNOTSUPP;
-
- /* clear bits to be modified and copy the flag values */
- priv->ctrlmode &= ~cm->mask;
- priv->ctrlmode |= maskedflags;
-
- /* CAN_CTRLMODE_FD can only be set when driver supports FD */
- if (priv->ctrlmode & CAN_CTRLMODE_FD)
- dev->mtu = CANFD_MTU;
- else
- dev->mtu = CAN_MTU;
- }
-
- if (data[IFLA_CAN_RESTART_MS]) {
- /* Do not allow changing restart delay while running */
- if (dev->flags & IFF_UP)
- return -EBUSY;
- priv->restart_ms = nla_get_u32(data[IFLA_CAN_RESTART_MS]);
- }
-
- if (data[IFLA_CAN_RESTART]) {
- /* Do not allow a restart while not running */
- if (!(dev->flags & IFF_UP))
- return -EINVAL;
- err = can_restart_now(dev);
- if (err)
- return err;
- }
-
- if (data[IFLA_CAN_DATA_BITTIMING]) {
- struct can_bittiming dbt;
-
- /* Do not allow changing bittiming while running */
- if (dev->flags & IFF_UP)
- return -EBUSY;
-
- /* Calculate bittiming parameters based on
- * data_bittiming_const if set, otherwise pass bitrate
- * directly via do_set_bitrate(). Bail out if neither
- * is given.
- */
- if (!priv->data_bittiming_const && !priv->do_set_data_bittiming)
- return -EOPNOTSUPP;
-
- memcpy(&dbt, nla_data(data[IFLA_CAN_DATA_BITTIMING]),
- sizeof(dbt));
- err = can_get_bittiming(dev, &dbt,
- priv->data_bittiming_const,
- priv->data_bitrate_const,
- priv->data_bitrate_const_cnt);
- if (err)
- return err;
-
- if (priv->bitrate_max && dbt.bitrate > priv->bitrate_max) {
- netdev_err(dev, "canfd data bitrate surpasses transceiver capabilities of %d bps\n",
- priv->bitrate_max);
- return -EINVAL;
- }
-
- memcpy(&priv->data_bittiming, &dbt, sizeof(dbt));
-
- if (priv->do_set_data_bittiming) {
- /* Finally, set the bit-timing registers */
- err = priv->do_set_data_bittiming(dev);
- if (err)
- return err;
- }
- }
-
- if (data[IFLA_CAN_TERMINATION]) {
- const u16 termval = nla_get_u16(data[IFLA_CAN_TERMINATION]);
- const unsigned int num_term = priv->termination_const_cnt;
- unsigned int i;
-
- if (!priv->do_set_termination)
- return -EOPNOTSUPP;
-
- /* check whether given value is supported by the interface */
- for (i = 0; i < num_term; i++) {
- if (termval == priv->termination_const[i])
- break;
- }
- if (i >= num_term)
- return -EINVAL;
-
- /* Finally, set the termination value */
- err = priv->do_set_termination(dev, termval);
- if (err)
- return err;
-
- priv->termination = termval;
- }
-
- return 0;
-}
-
-static size_t can_get_size(const struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
- size_t size = 0;
-
- if (priv->bittiming.bitrate) /* IFLA_CAN_BITTIMING */
- size += nla_total_size(sizeof(struct can_bittiming));
- if (priv->bittiming_const) /* IFLA_CAN_BITTIMING_CONST */
- size += nla_total_size(sizeof(struct can_bittiming_const));
- size += nla_total_size(sizeof(struct can_clock)); /* IFLA_CAN_CLOCK */
- size += nla_total_size(sizeof(u32)); /* IFLA_CAN_STATE */
- size += nla_total_size(sizeof(struct can_ctrlmode)); /* IFLA_CAN_CTRLMODE */
- size += nla_total_size(sizeof(u32)); /* IFLA_CAN_RESTART_MS */
- if (priv->do_get_berr_counter) /* IFLA_CAN_BERR_COUNTER */
- size += nla_total_size(sizeof(struct can_berr_counter));
- if (priv->data_bittiming.bitrate) /* IFLA_CAN_DATA_BITTIMING */
- size += nla_total_size(sizeof(struct can_bittiming));
- if (priv->data_bittiming_const) /* IFLA_CAN_DATA_BITTIMING_CONST */
- size += nla_total_size(sizeof(struct can_bittiming_const));
- if (priv->termination_const) {
- size += nla_total_size(sizeof(priv->termination)); /* IFLA_CAN_TERMINATION */
- size += nla_total_size(sizeof(*priv->termination_const) * /* IFLA_CAN_TERMINATION_CONST */
- priv->termination_const_cnt);
- }
- if (priv->bitrate_const) /* IFLA_CAN_BITRATE_CONST */
- size += nla_total_size(sizeof(*priv->bitrate_const) *
- priv->bitrate_const_cnt);
- if (priv->data_bitrate_const) /* IFLA_CAN_DATA_BITRATE_CONST */
- size += nla_total_size(sizeof(*priv->data_bitrate_const) *
- priv->data_bitrate_const_cnt);
- size += sizeof(priv->bitrate_max); /* IFLA_CAN_BITRATE_MAX */
-
- return size;
-}
-
-static int can_fill_info(struct sk_buff *skb, const struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
- struct can_ctrlmode cm = {.flags = priv->ctrlmode};
- struct can_berr_counter bec = { };
- enum can_state state = priv->state;
-
- if (priv->do_get_state)
- priv->do_get_state(dev, &state);
-
- if ((priv->bittiming.bitrate &&
- nla_put(skb, IFLA_CAN_BITTIMING,
- sizeof(priv->bittiming), &priv->bittiming)) ||
-
- (priv->bittiming_const &&
- nla_put(skb, IFLA_CAN_BITTIMING_CONST,
- sizeof(*priv->bittiming_const), priv->bittiming_const)) ||
-
- nla_put(skb, IFLA_CAN_CLOCK, sizeof(priv->clock), &priv->clock) ||
- nla_put_u32(skb, IFLA_CAN_STATE, state) ||
- nla_put(skb, IFLA_CAN_CTRLMODE, sizeof(cm), &cm) ||
- nla_put_u32(skb, IFLA_CAN_RESTART_MS, priv->restart_ms) ||
-
- (priv->do_get_berr_counter &&
- !priv->do_get_berr_counter(dev, &bec) &&
- nla_put(skb, IFLA_CAN_BERR_COUNTER, sizeof(bec), &bec)) ||
-
- (priv->data_bittiming.bitrate &&
- nla_put(skb, IFLA_CAN_DATA_BITTIMING,
- sizeof(priv->data_bittiming), &priv->data_bittiming)) ||
-
- (priv->data_bittiming_const &&
- nla_put(skb, IFLA_CAN_DATA_BITTIMING_CONST,
- sizeof(*priv->data_bittiming_const),
- priv->data_bittiming_const)) ||
-
- (priv->termination_const &&
- (nla_put_u16(skb, IFLA_CAN_TERMINATION, priv->termination) ||
- nla_put(skb, IFLA_CAN_TERMINATION_CONST,
- sizeof(*priv->termination_const) *
- priv->termination_const_cnt,
- priv->termination_const))) ||
-
- (priv->bitrate_const &&
- nla_put(skb, IFLA_CAN_BITRATE_CONST,
- sizeof(*priv->bitrate_const) *
- priv->bitrate_const_cnt,
- priv->bitrate_const)) ||
-
- (priv->data_bitrate_const &&
- nla_put(skb, IFLA_CAN_DATA_BITRATE_CONST,
- sizeof(*priv->data_bitrate_const) *
- priv->data_bitrate_const_cnt,
- priv->data_bitrate_const)) ||
-
- (nla_put(skb, IFLA_CAN_BITRATE_MAX,
- sizeof(priv->bitrate_max),
- &priv->bitrate_max))
- )
-
- return -EMSGSIZE;
-
- return 0;
-}
-
-static size_t can_get_xstats_size(const struct net_device *dev)
-{
- return sizeof(struct can_device_stats);
-}
-
-static int can_fill_xstats(struct sk_buff *skb, const struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- if (nla_put(skb, IFLA_INFO_XSTATS,
- sizeof(priv->can_stats), &priv->can_stats))
- goto nla_put_failure;
- return 0;
-
-nla_put_failure:
- return -EMSGSIZE;
-}
-
-static int can_newlink(struct net *src_net, struct net_device *dev,
- struct nlattr *tb[], struct nlattr *data[],
- struct netlink_ext_ack *extack)
-{
- return -EOPNOTSUPP;
-}
-
-static void can_dellink(struct net_device *dev, struct list_head *head)
-{
- return;
-}
-
-static struct rtnl_link_ops can_link_ops __read_mostly = {
- .kind = "can",
- .netns_refund = true,
- .maxtype = IFLA_CAN_MAX,
- .policy = can_policy,
- .setup = can_setup,
- .validate = can_validate,
- .newlink = can_newlink,
- .changelink = can_changelink,
- .dellink = can_dellink,
- .get_size = can_get_size,
- .fill_info = can_fill_info,
- .get_xstats_size = can_get_xstats_size,
- .fill_xstats = can_fill_xstats,
-};
-
-/*
- * Register the CAN network device
- */
-int register_candev(struct net_device *dev)
-{
- struct can_priv *priv = netdev_priv(dev);
-
- /* Ensure termination_const, termination_const_cnt and
- * do_set_termination consistency. All must be either set or
- * unset.
- */
- if ((!priv->termination_const != !priv->termination_const_cnt) ||
- (!priv->termination_const != !priv->do_set_termination))
- return -EINVAL;
-
- if (!priv->bitrate_const != !priv->bitrate_const_cnt)
- return -EINVAL;
-
- if (!priv->data_bitrate_const != !priv->data_bitrate_const_cnt)
- return -EINVAL;
-
- dev->rtnl_link_ops = &can_link_ops;
- netif_carrier_off(dev);
-
- return register_netdev(dev);
-}
-EXPORT_SYMBOL_GPL(register_candev);
-
-/*
- * Unregister the CAN network device
- */
-void unregister_candev(struct net_device *dev)
-{
- unregister_netdev(dev);
-}
-EXPORT_SYMBOL_GPL(unregister_candev);
-
-/*
- * Test if a network device is a candev based device
- * and return the can_priv* if so.
- */
-struct can_priv *safe_candev_priv(struct net_device *dev)
-{
- if ((dev->type != ARPHRD_CAN) || (dev->rtnl_link_ops != &can_link_ops))
- return NULL;
-
- return netdev_priv(dev);
-}
-EXPORT_SYMBOL_GPL(safe_candev_priv);
-
-static __init int can_dev_init(void)
-{
- int err;
-
- can_led_notifier_init();
-
- err = rtnl_link_register(&can_link_ops);
- if (!err)
- printk(KERN_INFO MOD_DESC "\n");
-
- return err;
-}
-module_init(can_dev_init);
-
-static __exit void can_dev_exit(void)
-{
- rtnl_link_unregister(&can_link_ops);
-
- can_led_notifier_exit();
-}
-module_exit(can_dev_exit);
-
-MODULE_ALIAS_RTNL_LINK("can");