linux/drivers/net/can/usb/etas_es58x/es58x_core.h
<<
>>
Prefs
   1/* SPDX-License-Identifier: GPL-2.0 */
   2
   3/* Driver for ETAS GmbH ES58X USB CAN(-FD) Bus Interfaces.
   4 *
   5 * File es58x_core.h: All common definitions and declarations.
   6 *
   7 * Copyright (c) 2019 Robert Bosch Engineering and Business Solutions. All rights reserved.
   8 * Copyright (c) 2020 ETAS K.K.. All rights reserved.
   9 * Copyright (c) 2020, 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr>
  10 */
  11
  12#ifndef __ES58X_COMMON_H__
  13#define __ES58X_COMMON_H__
  14
  15#include <linux/types.h>
  16#include <linux/usb.h>
  17#include <linux/netdevice.h>
  18#include <linux/can.h>
  19#include <linux/can/dev.h>
  20
  21#include "es581_4.h"
  22#include "es58x_fd.h"
  23
  24/* Driver constants */
  25#define ES58X_RX_URBS_MAX 5     /* Empirical value */
  26#define ES58X_TX_URBS_MAX 6     /* Empirical value */
  27
  28#define ES58X_MAX(param)                                \
  29        (ES581_4_##param > ES58X_FD_##param ?           \
  30                ES581_4_##param : ES58X_FD_##param)
  31#define ES58X_TX_BULK_MAX ES58X_MAX(TX_BULK_MAX)
  32#define ES58X_RX_BULK_MAX ES58X_MAX(RX_BULK_MAX)
  33#define ES58X_ECHO_BULK_MAX ES58X_MAX(ECHO_BULK_MAX)
  34#define ES58X_NUM_CAN_CH_MAX ES58X_MAX(NUM_CAN_CH)
  35
  36/* Use this when channel index is irrelevant (e.g. device
  37 * timestamp).
  38 */
  39#define ES58X_CHANNEL_IDX_NA 0xFF
  40#define ES58X_EMPTY_MSG NULL
  41
  42/* Threshold on consecutive CAN_STATE_ERROR_PASSIVE. If we receive
  43 * ES58X_CONSECUTIVE_ERR_PASSIVE_MAX times the event
  44 * ES58X_ERR_CRTL_PASSIVE in a row without any successful RX or TX,
  45 * we force the device to switch to CAN_STATE_BUS_OFF state.
  46 */
  47#define ES58X_CONSECUTIVE_ERR_PASSIVE_MAX 254
  48
  49/* A magic number sent by the ES581.4 to inform it is alive. */
  50#define ES58X_HEARTBEAT 0x11
  51
  52/**
  53 * enum es58x_driver_info - Quirks of the device.
  54 * @ES58X_DUAL_CHANNEL: Device has two CAN channels. If this flag is
  55 *      not set, it is implied that the device has only one CAN
  56 *      channel.
  57 * @ES58X_FD_FAMILY: Device is CAN-FD capable. If this flag is not
  58 *      set, the device only supports classical CAN.
  59 */
  60enum es58x_driver_info {
  61        ES58X_DUAL_CHANNEL = BIT(0),
  62        ES58X_FD_FAMILY = BIT(1)
  63};
  64
  65enum es58x_echo {
  66        ES58X_ECHO_OFF = 0,
  67        ES58X_ECHO_ON = 1
  68};
  69
  70/**
  71 * enum es58x_physical_layer - Type of the physical layer.
  72 * @ES58X_PHYSICAL_LAYER_HIGH_SPEED: High-speed CAN (c.f. ISO
  73 *      11898-2).
  74 *
  75 * Some products of the ETAS portfolio also support low-speed CAN
  76 * (c.f. ISO 11898-3). However, all the devices in scope of this
  77 * driver do not support the option, thus, the enum has only one
  78 * member.
  79 */
  80enum es58x_physical_layer {
  81        ES58X_PHYSICAL_LAYER_HIGH_SPEED = 1
  82};
  83
  84enum es58x_samples_per_bit {
  85        ES58X_SAMPLES_PER_BIT_ONE = 1,
  86        ES58X_SAMPLES_PER_BIT_THREE = 2
  87};
  88
  89/**
  90 * enum es58x_sync_edge - Synchronization method.
  91 * @ES58X_SYNC_EDGE_SINGLE: ISO CAN specification defines the use of a
  92 *      single edge synchronization.  The synchronization should be
  93 *      done on recessive to dominant level change.
  94 *
  95 * For information, ES582.1 and ES584.1 also support a double
  96 * synchronization, requiring both recessive to dominant then dominant
  97 * to recessive level change. However, this is not supported in
  98 * SocketCAN framework, thus, the enum has only one member.
  99 */
 100enum es58x_sync_edge {
 101        ES58X_SYNC_EDGE_SINGLE = 1
 102};
 103
 104/**
 105 * enum es58x_flag - CAN flags for RX/TX messages.
 106 * @ES58X_FLAG_EFF: Extended Frame Format (EFF).
 107 * @ES58X_FLAG_RTR: Remote Transmission Request (RTR).
 108 * @ES58X_FLAG_FD_BRS: Bit rate switch (BRS): second bitrate for
 109 *      payload data.
 110 * @ES58X_FLAG_FD_ESI: Error State Indicator (ESI): tell if the
 111 *      transmitting node is in error passive mode.
 112 * @ES58X_FLAG_FD_DATA: CAN FD frame.
 113 */
 114enum es58x_flag {
 115        ES58X_FLAG_EFF = BIT(0),
 116        ES58X_FLAG_RTR = BIT(1),
 117        ES58X_FLAG_FD_BRS = BIT(3),
 118        ES58X_FLAG_FD_ESI = BIT(5),
 119        ES58X_FLAG_FD_DATA = BIT(6)
 120};
 121
 122/**
 123 * enum es58x_err - CAN error detection.
 124 * @ES58X_ERR_OK: No errors.
 125 * @ES58X_ERR_PROT_STUFF: Bit stuffing error: more than 5 consecutive
 126 *      equal bits.
 127 * @ES58X_ERR_PROT_FORM: Frame format error.
 128 * @ES58X_ERR_ACK: Received no ACK on transmission.
 129 * @ES58X_ERR_PROT_BIT: Single bit error.
 130 * @ES58X_ERR_PROT_CRC: Incorrect 15, 17 or 21 bits CRC.
 131 * @ES58X_ERR_PROT_BIT1: Unable to send recessive bit: tried to send
 132 *      recessive bit 1 but monitored dominant bit 0.
 133 * @ES58X_ERR_PROT_BIT0: Unable to send dominant bit: tried to send
 134 *      dominant bit 0 but monitored recessive bit 1.
 135 * @ES58X_ERR_PROT_OVERLOAD: Bus overload.
 136 * @ES58X_ERR_PROT_UNSPEC: Unspecified.
 137 *
 138 * Please refer to ISO 11898-1:2015, section 10.11 "Error detection"
 139 * and section 10.13 "Overload signaling" for additional details.
 140 */
 141enum es58x_err {
 142        ES58X_ERR_OK = 0,
 143        ES58X_ERR_PROT_STUFF = BIT(0),
 144        ES58X_ERR_PROT_FORM = BIT(1),
 145        ES58X_ERR_ACK = BIT(2),
 146        ES58X_ERR_PROT_BIT = BIT(3),
 147        ES58X_ERR_PROT_CRC = BIT(4),
 148        ES58X_ERR_PROT_BIT1 = BIT(5),
 149        ES58X_ERR_PROT_BIT0 = BIT(6),
 150        ES58X_ERR_PROT_OVERLOAD = BIT(7),
 151        ES58X_ERR_PROT_UNSPEC = BIT(31)
 152};
 153
 154/**
 155 * enum es58x_event - CAN error codes returned by the device.
 156 * @ES58X_EVENT_OK: No errors.
 157 * @ES58X_EVENT_CRTL_ACTIVE: Active state: both TR and RX error count
 158 *      is less than 128.
 159 * @ES58X_EVENT_CRTL_PASSIVE: Passive state: either TX or RX error
 160 *      count is greater than 127.
 161 * @ES58X_EVENT_CRTL_WARNING: Warning state: either TX or RX error
 162 *      count is greater than 96.
 163 * @ES58X_EVENT_BUSOFF: Bus off.
 164 * @ES58X_EVENT_SINGLE_WIRE: Lost connection on either CAN high or CAN
 165 *      low.
 166 *
 167 * Please refer to ISO 11898-1:2015, section 12.1.4 "Rules of fault
 168 * confinement" for additional details.
 169 */
 170enum es58x_event {
 171        ES58X_EVENT_OK = 0,
 172        ES58X_EVENT_CRTL_ACTIVE = BIT(0),
 173        ES58X_EVENT_CRTL_PASSIVE = BIT(1),
 174        ES58X_EVENT_CRTL_WARNING = BIT(2),
 175        ES58X_EVENT_BUSOFF = BIT(3),
 176        ES58X_EVENT_SINGLE_WIRE = BIT(4)
 177};
 178
 179/* enum es58x_ret_u8 - Device return error codes, 8 bit format.
 180 *
 181 * Specific to ES581.4.
 182 */
 183enum es58x_ret_u8 {
 184        ES58X_RET_U8_OK = 0x00,
 185        ES58X_RET_U8_ERR_UNSPECIFIED_FAILURE = 0x80,
 186        ES58X_RET_U8_ERR_NO_MEM = 0x81,
 187        ES58X_RET_U8_ERR_BAD_CRC = 0x99
 188};
 189
 190/* enum es58x_ret_u32 - Device return error codes, 32 bit format.
 191 */
 192enum es58x_ret_u32 {
 193        ES58X_RET_U32_OK = 0x00000000UL,
 194        ES58X_RET_U32_ERR_UNSPECIFIED_FAILURE = 0x80000000UL,
 195        ES58X_RET_U32_ERR_NO_MEM = 0x80004001UL,
 196        ES58X_RET_U32_WARN_PARAM_ADJUSTED = 0x40004000UL,
 197        ES58X_RET_U32_WARN_TX_MAYBE_REORDER = 0x40004001UL,
 198        ES58X_RET_U32_ERR_TIMEDOUT = 0x80000008UL,
 199        ES58X_RET_U32_ERR_FIFO_FULL = 0x80003002UL,
 200        ES58X_RET_U32_ERR_BAD_CONFIG = 0x80004000UL,
 201        ES58X_RET_U32_ERR_NO_RESOURCE = 0x80004002UL
 202};
 203
 204/* enum es58x_ret_type - Type of the command returned by the ES58X
 205 *      device.
 206 */
 207enum es58x_ret_type {
 208        ES58X_RET_TYPE_SET_BITTIMING,
 209        ES58X_RET_TYPE_ENABLE_CHANNEL,
 210        ES58X_RET_TYPE_DISABLE_CHANNEL,
 211        ES58X_RET_TYPE_TX_MSG,
 212        ES58X_RET_TYPE_RESET_RX,
 213        ES58X_RET_TYPE_RESET_TX,
 214        ES58X_RET_TYPE_DEVICE_ERR
 215};
 216
 217union es58x_urb_cmd {
 218        struct es581_4_urb_cmd es581_4_urb_cmd;
 219        struct es58x_fd_urb_cmd es58x_fd_urb_cmd;
 220        struct {                /* Common header parts of all variants */
 221                __le16 sof;
 222                u8 cmd_type;
 223                u8 cmd_id;
 224        } __packed;
 225        u8 raw_cmd[0];
 226};
 227
 228/**
 229 * struct es58x_priv - All information specific to a CAN channel.
 230 * @can: struct can_priv must be the first member (Socket CAN relies
 231 *      on the fact that function netdev_priv() returns a pointer to
 232 *      a struct can_priv).
 233 * @es58x_dev: pointer to the corresponding ES58X device.
 234 * @tx_urb: Used as a buffer to concatenate the TX messages and to do
 235 *      a bulk send. Please refer to es58x_start_xmit() for more
 236 *      details.
 237 * @tx_tail: Index of the oldest packet still pending for
 238 *      completion. @tx_tail & echo_skb_mask represents the beginning
 239 *      of the echo skb FIFO, i.e. index of the first element.
 240 * @tx_head: Index of the next packet to be sent to the
 241 *      device. @tx_head & echo_skb_mask represents the end of the
 242 *      echo skb FIFO plus one, i.e. the first free index.
 243 * @tx_can_msg_cnt: Number of messages in @tx_urb.
 244 * @tx_can_msg_is_fd: false: all messages in @tx_urb are Classical
 245 *      CAN, true: all messages in @tx_urb are CAN FD. Rationale:
 246 *      ES58X FD devices do not allow to mix Classical CAN and FD CAN
 247 *      frames in one single bulk transmission.
 248 * @err_passive_before_rtx_success: The ES58X device might enter in a
 249 *      state in which it keeps alternating between error passive
 250 *      and active states. This counter keeps track of the number of
 251 *      error passive and if it gets bigger than
 252 *      ES58X_CONSECUTIVE_ERR_PASSIVE_MAX, es58x_rx_err_msg() will
 253 *      force the status to bus-off.
 254 * @channel_idx: Channel index, starts at zero.
 255 */
 256struct es58x_priv {
 257        struct can_priv can;
 258        struct es58x_device *es58x_dev;
 259        struct urb *tx_urb;
 260
 261        u32 tx_tail;
 262        u32 tx_head;
 263
 264        u8 tx_can_msg_cnt;
 265        bool tx_can_msg_is_fd;
 266
 267        u8 err_passive_before_rtx_success;
 268
 269        u8 channel_idx;
 270};
 271
 272/**
 273 * struct es58x_parameters - Constant parameters of a given hardware
 274 *      variant.
 275 * @bittiming_const: Nominal bittimming constant parameters.
 276 * @data_bittiming_const: Data bittiming constant parameters.
 277 * @tdc_const: Transmission Delay Compensation constant parameters.
 278 * @bitrate_max: Maximum bitrate supported by the device.
 279 * @clock: CAN clock parameters.
 280 * @ctrlmode_supported: List of supported modes. Please refer to
 281 *      can/netlink.h file for additional details.
 282 * @tx_start_of_frame: Magic number at the beginning of each TX URB
 283 *      command.
 284 * @rx_start_of_frame: Magic number at the beginning of each RX URB
 285 *      command.
 286 * @tx_urb_cmd_max_len: Maximum length of a TX URB command.
 287 * @rx_urb_cmd_max_len: Maximum length of a RX URB command.
 288 * @fifo_mask: Bit mask to quickly convert the tx_tail and tx_head
 289 *      field of the struct es58x_priv into echo_skb
 290 *      indexes. Properties: @fifo_mask = echo_skb_max - 1 where
 291 *      echo_skb_max must be a power of two. Also, echo_skb_max must
 292 *      not exceed the maximum size of the device internal TX FIFO
 293 *      length. This parameter is used to control the network queue
 294 *      wake/stop logic.
 295 * @dql_min_limit: Dynamic Queue Limits (DQL) absolute minimum limit
 296 *      of bytes allowed to be queued on this network device transmit
 297 *      queue. Used by the Byte Queue Limits (BQL) to determine how
 298 *      frequently the xmit_more flag will be set to true in
 299 *      es58x_start_xmit(). Set this value higher to optimize for
 300 *      throughput but be aware that it might have a negative impact
 301 *      on the latency! This value can also be set dynamically. Please
 302 *      refer to Documentation/ABI/testing/sysfs-class-net-queues for
 303 *      more details.
 304 * @tx_bulk_max: Maximum number of TX messages that can be sent in one
 305 *      single URB packet.
 306 * @urb_cmd_header_len: Length of the URB command header.
 307 * @rx_urb_max: Number of RX URB to be allocated during device probe.
 308 * @tx_urb_max: Number of TX URB to be allocated during device probe.
 309 */
 310struct es58x_parameters {
 311        const struct can_bittiming_const *bittiming_const;
 312        const struct can_bittiming_const *data_bittiming_const;
 313        const struct can_tdc_const *tdc_const;
 314        u32 bitrate_max;
 315        struct can_clock clock;
 316        u32 ctrlmode_supported;
 317        u16 tx_start_of_frame;
 318        u16 rx_start_of_frame;
 319        u16 tx_urb_cmd_max_len;
 320        u16 rx_urb_cmd_max_len;
 321        u16 fifo_mask;
 322        u16 dql_min_limit;
 323        u8 tx_bulk_max;
 324        u8 urb_cmd_header_len;
 325        u8 rx_urb_max;
 326        u8 tx_urb_max;
 327};
 328
 329/**
 330 * struct es58x_operators - Function pointers used to encode/decode
 331 *      the TX/RX messages.
 332 * @get_msg_len: Get field msg_len of the urb_cmd. The offset of
 333 *      msg_len inside urb_cmd depends of the device model.
 334 * @handle_urb_cmd: Decode the URB command received from the device
 335 *      and dispatch it to the relevant sub function.
 336 * @fill_urb_header: Fill the header of urb_cmd.
 337 * @tx_can_msg: Encode a TX CAN message and add it to the bulk buffer
 338 *      cmd_buf of es58x_dev.
 339 * @enable_channel: Start the CAN channel.
 340 * @disable_channel: Stop the CAN channel.
 341 * @reset_device: Full reset of the device. N.B: this feature is only
 342 *      present on the ES581.4. For ES58X FD devices, this field is
 343 *      set to NULL.
 344 * @get_timestamp: Request a timestamp from the ES58X device.
 345 */
 346struct es58x_operators {
 347        u16 (*get_msg_len)(const union es58x_urb_cmd *urb_cmd);
 348        int (*handle_urb_cmd)(struct es58x_device *es58x_dev,
 349                              const union es58x_urb_cmd *urb_cmd);
 350        void (*fill_urb_header)(union es58x_urb_cmd *urb_cmd, u8 cmd_type,
 351                                u8 cmd_id, u8 channel_idx, u16 cmd_len);
 352        int (*tx_can_msg)(struct es58x_priv *priv, const struct sk_buff *skb);
 353        int (*enable_channel)(struct es58x_priv *priv);
 354        int (*disable_channel)(struct es58x_priv *priv);
 355        int (*reset_device)(struct es58x_device *es58x_dev);
 356        int (*get_timestamp)(struct es58x_device *es58x_dev);
 357};
 358
 359/**
 360 * struct es58x_device - All information specific to an ES58X device.
 361 * @dev: Device information.
 362 * @udev: USB device information.
 363 * @netdev: Array of our CAN channels.
 364 * @param: The constant parameters.
 365 * @ops: Operators.
 366 * @rx_pipe: USB reception pipe.
 367 * @tx_pipe: USB transmission pipe.
 368 * @rx_urbs: Anchor for received URBs.
 369 * @tx_urbs_busy: Anchor for TX URBs which were send to the device.
 370 * @tx_urbs_idle: Anchor for TX USB which are idle. This driver
 371 *      allocates the memory for the URBs during the probe. When a TX
 372 *      URB is needed, it can be taken from this anchor. The network
 373 *      queue wake/stop logic should prevent this URB from getting
 374 *      empty. Please refer to es58x_get_tx_urb() for more details.
 375 * @tx_urbs_idle_cnt: number of urbs in @tx_urbs_idle.
 376 * @opened_channel_cnt: number of channels opened (c.f. es58x_open()
 377 *      and es58x_stop()).
 378 * @ktime_req_ns: kernel timestamp when es58x_set_realtime_diff_ns()
 379 *      was called.
 380 * @realtime_diff_ns: difference in nanoseconds between the clocks of
 381 *      the ES58X device and the kernel.
 382 * @timestamps: a temporary buffer to store the time stamps before
 383 *      feeding them to es58x_can_get_echo_skb(). Can only be used
 384 *      in RX branches.
 385 * @rx_max_packet_size: Maximum length of bulk-in URB.
 386 * @num_can_ch: Number of CAN channel (i.e. number of elements of @netdev).
 387 * @rx_cmd_buf_len: Length of @rx_cmd_buf.
 388 * @rx_cmd_buf: The device might split the URB commands in an
 389 *      arbitrary amount of pieces. This buffer is used to concatenate
 390 *      all those pieces. Can only be used in RX branches. This field
 391 *      has to be the last one of the structure because it is has a
 392 *      flexible size (c.f. es58x_sizeof_es58x_device() function).
 393 */
 394struct es58x_device {
 395        struct device *dev;
 396        struct usb_device *udev;
 397        struct net_device *netdev[ES58X_NUM_CAN_CH_MAX];
 398
 399        const struct es58x_parameters *param;
 400        const struct es58x_operators *ops;
 401
 402        int rx_pipe;
 403        int tx_pipe;
 404
 405        struct usb_anchor rx_urbs;
 406        struct usb_anchor tx_urbs_busy;
 407        struct usb_anchor tx_urbs_idle;
 408        atomic_t tx_urbs_idle_cnt;
 409        atomic_t opened_channel_cnt;
 410
 411        u64 ktime_req_ns;
 412        s64 realtime_diff_ns;
 413
 414        u64 timestamps[ES58X_ECHO_BULK_MAX];
 415
 416        u16 rx_max_packet_size;
 417        u8 num_can_ch;
 418
 419        u16 rx_cmd_buf_len;
 420        union es58x_urb_cmd rx_cmd_buf;
 421};
 422
 423/**
 424 * es58x_sizeof_es58x_device() - Calculate the maximum length of
 425 *      struct es58x_device.
 426 * @es58x_dev_param: The constant parameters of the device.
 427 *
 428 * The length of struct es58x_device depends on the length of its last
 429 * field: rx_cmd_buf. This macro allows to optimize the memory
 430 * allocation.
 431 *
 432 * Return: length of struct es58x_device.
 433 */
 434static inline size_t es58x_sizeof_es58x_device(const struct es58x_parameters
 435                                               *es58x_dev_param)
 436{
 437        return offsetof(struct es58x_device, rx_cmd_buf) +
 438                es58x_dev_param->rx_urb_cmd_max_len;
 439}
 440
 441static inline int __es58x_check_msg_len(const struct device *dev,
 442                                        const char *stringified_msg,
 443                                        size_t actual_len, size_t expected_len)
 444{
 445        if (expected_len != actual_len) {
 446                dev_err(dev,
 447                        "Length of %s is %zu but received command is %zu.\n",
 448                        stringified_msg, expected_len, actual_len);
 449                return -EMSGSIZE;
 450        }
 451        return 0;
 452}
 453
 454/**
 455 * es58x_check_msg_len() - Check the size of a received message.
 456 * @dev: Device, used to print error messages.
 457 * @msg: Received message, must not be a pointer.
 458 * @actual_len: Length of the message as advertised in the command header.
 459 *
 460 * Must be a macro in order to accept the different types of messages
 461 * as an input. Can be use with any of the messages which have a fixed
 462 * length. Check for an exact match of the size.
 463 *
 464 * Return: zero on success, -EMSGSIZE if @actual_len differs from the
 465 * expected length.
 466 */
 467#define es58x_check_msg_len(dev, msg, actual_len)                       \
 468        __es58x_check_msg_len(dev, __stringify(msg),                    \
 469                              actual_len, sizeof(msg))
 470
 471static inline int __es58x_check_msg_max_len(const struct device *dev,
 472                                            const char *stringified_msg,
 473                                            size_t actual_len,
 474                                            size_t expected_len)
 475{
 476        if (actual_len > expected_len) {
 477                dev_err(dev,
 478                        "Maximum length for %s is %zu but received command is %zu.\n",
 479                        stringified_msg, expected_len, actual_len);
 480                return -EOVERFLOW;
 481        }
 482        return 0;
 483}
 484
 485/**
 486 * es58x_check_msg_max_len() - Check the maximum size of a received message.
 487 * @dev: Device, used to print error messages.
 488 * @msg: Received message, must not be a pointer.
 489 * @actual_len: Length of the message as advertised in the command header.
 490 *
 491 * Must be a macro in order to accept the different types of messages
 492 * as an input. To be used with the messages of variable sizes. Only
 493 * check that the message is not bigger than the maximum expected
 494 * size.
 495 *
 496 * Return: zero on success, -EOVERFLOW if @actual_len is greater than
 497 * the expected length.
 498 */
 499#define es58x_check_msg_max_len(dev, msg, actual_len)                   \
 500        __es58x_check_msg_max_len(dev, __stringify(msg),                \
 501                                  actual_len, sizeof(msg))
 502
 503static inline int __es58x_msg_num_element(const struct device *dev,
 504                                          const char *stringified_msg,
 505                                          size_t actual_len, size_t msg_len,
 506                                          size_t elem_len)
 507{
 508        size_t actual_num_elem = actual_len / elem_len;
 509        size_t expected_num_elem = msg_len / elem_len;
 510
 511        if (actual_num_elem == 0) {
 512                dev_err(dev,
 513                        "Minimum length for %s is %zu but received command is %zu.\n",
 514                        stringified_msg, elem_len, actual_len);
 515                return -EMSGSIZE;
 516        } else if ((actual_len % elem_len) != 0) {
 517                dev_err(dev,
 518                        "Received command length: %zu is not a multiple of %s[0]: %zu\n",
 519                        actual_len, stringified_msg, elem_len);
 520                return -EMSGSIZE;
 521        } else if (actual_num_elem > expected_num_elem) {
 522                dev_err(dev,
 523                        "Array %s is supposed to have %zu elements each of size %zu...\n",
 524                        stringified_msg, expected_num_elem, elem_len);
 525                dev_err(dev,
 526                        "... But received command has %zu elements (total length %zu).\n",
 527                        actual_num_elem, actual_len);
 528                return -EOVERFLOW;
 529        }
 530        return actual_num_elem;
 531}
 532
 533/**
 534 * es58x_msg_num_element() - Check size and give the number of
 535 *      elements in a message of array type.
 536 * @dev: Device, used to print error messages.
 537 * @msg: Received message, must be an array.
 538 * @actual_len: Length of the message as advertised in the command
 539 *      header.
 540 *
 541 * Must be a macro in order to accept the different types of messages
 542 * as an input. To be used on message of array type. Array's element
 543 * has to be of fixed size (else use es58x_check_msg_max_len()). Check
 544 * that the total length is an exact multiple of the length of a
 545 * single element.
 546 *
 547 * Return: number of elements in the array on success, -EOVERFLOW if
 548 * @actual_len is greater than the expected length, -EMSGSIZE if
 549 * @actual_len is not a multiple of a single element.
 550 */
 551#define es58x_msg_num_element(dev, msg, actual_len)                     \
 552({                                                                      \
 553        size_t __elem_len = sizeof((msg)[0]) + __must_be_array(msg);    \
 554        __es58x_msg_num_element(dev, __stringify(msg), actual_len,      \
 555                                sizeof(msg), __elem_len);               \
 556})
 557
 558/**
 559 * es58x_priv() - Get the priv member and cast it to struct es58x_priv.
 560 * @netdev: CAN network device.
 561 *
 562 * Return: ES58X device.
 563 */
 564static inline struct es58x_priv *es58x_priv(struct net_device *netdev)
 565{
 566        return (struct es58x_priv *)netdev_priv(netdev);
 567}
 568
 569/**
 570 * ES58X_SIZEOF_URB_CMD() - Calculate the maximum length of an urb
 571 *      command for a given message field name.
 572 * @es58x_urb_cmd_type: type (either "struct es581_4_urb_cmd" or
 573 *      "struct es58x_fd_urb_cmd").
 574 * @msg_field: name of the message field.
 575 *
 576 * Must be a macro in order to accept the different command types as
 577 * an input.
 578 *
 579 * Return: length of the urb command.
 580 */
 581#define ES58X_SIZEOF_URB_CMD(es58x_urb_cmd_type, msg_field)             \
 582        (offsetof(es58x_urb_cmd_type, raw_msg)                          \
 583                + sizeof_field(es58x_urb_cmd_type, msg_field)           \
 584                + sizeof_field(es58x_urb_cmd_type,                      \
 585                               reserved_for_crc16_do_not_use))
 586
 587/**
 588 * es58x_get_urb_cmd_len() - Calculate the actual length of an urb
 589 *      command for a given message length.
 590 * @es58x_dev: ES58X device.
 591 * @msg_len: Length of the message.
 592 *
 593 * Add the header and CRC lengths to the message length.
 594 *
 595 * Return: length of the urb command.
 596 */
 597static inline size_t es58x_get_urb_cmd_len(struct es58x_device *es58x_dev,
 598                                           u16 msg_len)
 599{
 600        return es58x_dev->param->urb_cmd_header_len + msg_len + sizeof(u16);
 601}
 602
 603/**
 604 * es58x_get_netdev() - Get the network device.
 605 * @es58x_dev: ES58X device.
 606 * @channel_no: The channel number as advertised in the urb command.
 607 * @channel_idx_offset: Some of the ES58x starts channel numbering
 608 *      from 0 (ES58X FD), others from 1 (ES581.4).
 609 * @netdev: CAN network device.
 610 *
 611 * Do a sanity check on the index provided by the device.
 612 *
 613 * Return: zero on success, -ECHRNG if the received channel number is
 614 *      out of range and -ENODEV if the network device is not yet
 615 *      configured.
 616 */
 617static inline int es58x_get_netdev(struct es58x_device *es58x_dev,
 618                                   int channel_no, int channel_idx_offset,
 619                                   struct net_device **netdev)
 620{
 621        int channel_idx = channel_no - channel_idx_offset;
 622
 623        *netdev = NULL;
 624        if (channel_idx < 0 || channel_idx >= es58x_dev->num_can_ch)
 625                return -ECHRNG;
 626
 627        *netdev = es58x_dev->netdev[channel_idx];
 628        if (!*netdev || !netif_device_present(*netdev))
 629                return -ENODEV;
 630
 631        return 0;
 632}
 633
 634/**
 635 * es58x_get_raw_can_id() - Get the CAN ID.
 636 * @cf: CAN frame.
 637 *
 638 * Mask the CAN ID in order to only keep the significant bits.
 639 *
 640 * Return: the raw value of the CAN ID.
 641 */
 642static inline int es58x_get_raw_can_id(const struct can_frame *cf)
 643{
 644        if (cf->can_id & CAN_EFF_FLAG)
 645                return cf->can_id & CAN_EFF_MASK;
 646        else
 647                return cf->can_id & CAN_SFF_MASK;
 648}
 649
 650/**
 651 * es58x_get_flags() - Get the CAN flags.
 652 * @skb: socket buffer of a CAN message.
 653 *
 654 * Return: the CAN flag as an enum es58x_flag.
 655 */
 656static inline enum es58x_flag es58x_get_flags(const struct sk_buff *skb)
 657{
 658        struct canfd_frame *cf = (struct canfd_frame *)skb->data;
 659        enum es58x_flag es58x_flags = 0;
 660
 661        if (cf->can_id & CAN_EFF_FLAG)
 662                es58x_flags |= ES58X_FLAG_EFF;
 663
 664        if (can_is_canfd_skb(skb)) {
 665                es58x_flags |= ES58X_FLAG_FD_DATA;
 666                if (cf->flags & CANFD_BRS)
 667                        es58x_flags |= ES58X_FLAG_FD_BRS;
 668                if (cf->flags & CANFD_ESI)
 669                        es58x_flags |= ES58X_FLAG_FD_ESI;
 670        } else if (cf->can_id & CAN_RTR_FLAG)
 671                /* Remote frames are only defined in Classical CAN frames */
 672                es58x_flags |= ES58X_FLAG_RTR;
 673
 674        return es58x_flags;
 675}
 676
 677int es58x_can_get_echo_skb(struct net_device *netdev, u32 packet_idx,
 678                           u64 *tstamps, unsigned int pkts);
 679int es58x_tx_ack_msg(struct net_device *netdev, u16 tx_free_entries,
 680                     enum es58x_ret_u32 rx_cmd_ret_u32);
 681int es58x_rx_can_msg(struct net_device *netdev, u64 timestamp, const u8 *data,
 682                     canid_t can_id, enum es58x_flag es58x_flags, u8 dlc);
 683int es58x_rx_err_msg(struct net_device *netdev, enum es58x_err error,
 684                     enum es58x_event event, u64 timestamp);
 685void es58x_rx_timestamp(struct es58x_device *es58x_dev, u64 timestamp);
 686int es58x_rx_cmd_ret_u8(struct device *dev, enum es58x_ret_type cmd_ret_type,
 687                        enum es58x_ret_u8 rx_cmd_ret_u8);
 688int es58x_rx_cmd_ret_u32(struct net_device *netdev,
 689                         enum es58x_ret_type cmd_ret_type,
 690                         enum es58x_ret_u32 rx_cmd_ret_u32);
 691int es58x_send_msg(struct es58x_device *es58x_dev, u8 cmd_type, u8 cmd_id,
 692                   const void *msg, u16 cmd_len, int channel_idx);
 693
 694extern const struct es58x_parameters es581_4_param;
 695extern const struct es58x_operators es581_4_ops;
 696
 697extern const struct es58x_parameters es58x_fd_param;
 698extern const struct es58x_operators es58x_fd_ops;
 699
 700#endif /* __ES58X_COMMON_H__ */
 701