1 // SPDX-License-Identifier: GPL-2.0
2
3 /* Driver for ETAS GmbH ES58X USB CAN(-FD) Bus Interfaces.
4 *
5 * File es58x_fd.c: Adds support to ETAS ES582.1 and ES584.1 (naming
6 * convention: we use the term "ES58X FD" when referring to those two
7 * variants together).
8 *
9 * Copyright (c) 2019 Robert Bosch Engineering and Business Solutions. All rights reserved.
10 * Copyright (c) 2020 ETAS K.K.. All rights reserved.
11 * Copyright (c) 2020, 2021 Vincent Mailhol <mailhol.vincent@wanadoo.fr>
12 */
13
14 #include <linux/kernel.h>
15 #include <asm/unaligned.h>
16
17 #include "es58x_core.h"
18 #include "es58x_fd.h"
19
20 /**
21 * es58x_fd_sizeof_rx_tx_msg() - Calculate the actual length of the
22 * structure of a rx or tx message.
23 * @msg: message of variable length, must have a dlc and a len fields.
24 *
25 * Even if RTR frames have actually no payload, the ES58X devices
26 * still expect it. Must be a macro in order to accept several types
27 * (struct es58x_fd_tx_can_msg and struct es58x_fd_rx_can_msg) as an
28 * input.
29 *
30 * Return: length of the message.
31 */
32 #define es58x_fd_sizeof_rx_tx_msg(msg) \
33 ({ \
34 typeof(msg) __msg = (msg); \
35 size_t __msg_len; \
36 \
37 if (__msg.flags & ES58X_FLAG_FD_DATA) \
38 __msg_len = canfd_sanitize_len(__msg.len); \
39 else \
40 __msg_len = can_cc_dlc2len(__msg.dlc); \
41 \
42 offsetof(typeof(__msg), data[__msg_len]); \
43 })
44
es58x_fd_cmd_type(struct net_device * netdev)45 static enum es58x_fd_cmd_type es58x_fd_cmd_type(struct net_device *netdev)
46 {
47 u32 ctrlmode = es58x_priv(netdev)->can.ctrlmode;
48
49 if (ctrlmode & (CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO))
50 return ES58X_FD_CMD_TYPE_CANFD;
51 else
52 return ES58X_FD_CMD_TYPE_CAN;
53 }
54
es58x_fd_get_msg_len(const union es58x_urb_cmd * urb_cmd)55 static u16 es58x_fd_get_msg_len(const union es58x_urb_cmd *urb_cmd)
56 {
57 return get_unaligned_le16(&urb_cmd->es58x_fd_urb_cmd.msg_len);
58 }
59
es58x_fd_echo_msg(struct net_device * netdev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd)60 static int es58x_fd_echo_msg(struct net_device *netdev,
61 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
62 {
63 struct es58x_priv *priv = es58x_priv(netdev);
64 const struct es58x_fd_echo_msg *echo_msg;
65 struct es58x_device *es58x_dev = priv->es58x_dev;
66 u64 *tstamps = es58x_dev->timestamps;
67 u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
68 int i, num_element;
69 u32 rcv_packet_idx;
70
71 const u32 mask = GENMASK(31, sizeof(echo_msg->packet_idx) * 8);
72
73 num_element = es58x_msg_num_element(es58x_dev->dev,
74 es58x_fd_urb_cmd->echo_msg,
75 msg_len);
76 if (num_element < 0)
77 return num_element;
78 echo_msg = es58x_fd_urb_cmd->echo_msg;
79
80 rcv_packet_idx = (priv->tx_tail & mask) | echo_msg[0].packet_idx;
81 for (i = 0; i < num_element; i++) {
82 if ((u8)rcv_packet_idx != echo_msg[i].packet_idx) {
83 netdev_err(netdev, "Packet idx jumped from %u to %u\n",
84 (u8)rcv_packet_idx - 1,
85 echo_msg[i].packet_idx);
86 return -EBADMSG;
87 }
88
89 tstamps[i] = get_unaligned_le64(&echo_msg[i].timestamp);
90 rcv_packet_idx++;
91 }
92
93 return es58x_can_get_echo_skb(netdev, priv->tx_tail, tstamps, num_element);
94 }
95
es58x_fd_rx_can_msg(struct net_device * netdev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd)96 static int es58x_fd_rx_can_msg(struct net_device *netdev,
97 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
98 {
99 struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
100 const u8 *rx_can_msg_buf = es58x_fd_urb_cmd->rx_can_msg_buf;
101 u16 rx_can_msg_buf_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
102 int pkts, ret;
103
104 ret = es58x_check_msg_max_len(es58x_dev->dev,
105 es58x_fd_urb_cmd->rx_can_msg_buf,
106 rx_can_msg_buf_len);
107 if (ret)
108 return ret;
109
110 for (pkts = 0; rx_can_msg_buf_len > 0; pkts++) {
111 const struct es58x_fd_rx_can_msg *rx_can_msg =
112 (const struct es58x_fd_rx_can_msg *)rx_can_msg_buf;
113 bool is_can_fd = !!(rx_can_msg->flags & ES58X_FLAG_FD_DATA);
114 /* rx_can_msg_len is the length of the rx_can_msg
115 * buffer. Not to be confused with rx_can_msg->len
116 * which is the length of the CAN payload
117 * rx_can_msg->data.
118 */
119 u16 rx_can_msg_len = es58x_fd_sizeof_rx_tx_msg(*rx_can_msg);
120
121 if (rx_can_msg_len > rx_can_msg_buf_len) {
122 netdev_err(netdev,
123 "%s: Expected a rx_can_msg of size %d but only %d bytes are left in rx_can_msg_buf\n",
124 __func__,
125 rx_can_msg_len, rx_can_msg_buf_len);
126 return -EMSGSIZE;
127 }
128 if (rx_can_msg->len > CANFD_MAX_DLEN) {
129 netdev_err(netdev,
130 "%s: Data length is %d but maximum should be %d\n",
131 __func__, rx_can_msg->len, CANFD_MAX_DLEN);
132 return -EMSGSIZE;
133 }
134
135 if (netif_running(netdev)) {
136 u64 tstamp = get_unaligned_le64(&rx_can_msg->timestamp);
137 canid_t can_id = get_unaligned_le32(&rx_can_msg->can_id);
138 u8 dlc;
139
140 if (is_can_fd)
141 dlc = can_fd_len2dlc(rx_can_msg->len);
142 else
143 dlc = rx_can_msg->dlc;
144
145 ret = es58x_rx_can_msg(netdev, tstamp, rx_can_msg->data,
146 can_id, rx_can_msg->flags, dlc);
147 if (ret)
148 break;
149 }
150
151 rx_can_msg_buf_len -= rx_can_msg_len;
152 rx_can_msg_buf += rx_can_msg_len;
153 }
154
155 if (!netif_running(netdev)) {
156 if (net_ratelimit())
157 netdev_info(netdev,
158 "%s: %s is down, dropping %d rx packets\n",
159 __func__, netdev->name, pkts);
160 netdev->stats.rx_dropped += pkts;
161 }
162
163 return ret;
164 }
165
es58x_fd_rx_event_msg(struct net_device * netdev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd)166 static int es58x_fd_rx_event_msg(struct net_device *netdev,
167 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
168 {
169 struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
170 u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
171 const struct es58x_fd_rx_event_msg *rx_event_msg;
172 int ret;
173
174 ret = es58x_check_msg_len(es58x_dev->dev, *rx_event_msg, msg_len);
175 if (ret)
176 return ret;
177
178 rx_event_msg = &es58x_fd_urb_cmd->rx_event_msg;
179
180 return es58x_rx_err_msg(netdev, rx_event_msg->error_code,
181 rx_event_msg->event_code,
182 get_unaligned_le64(&rx_event_msg->timestamp));
183 }
184
es58x_fd_rx_cmd_ret_u32(struct net_device * netdev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd,enum es58x_ret_type cmd_ret_type)185 static int es58x_fd_rx_cmd_ret_u32(struct net_device *netdev,
186 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd,
187 enum es58x_ret_type cmd_ret_type)
188 {
189 struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
190 u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
191 int ret;
192
193 ret = es58x_check_msg_len(es58x_dev->dev,
194 es58x_fd_urb_cmd->rx_cmd_ret_le32, msg_len);
195 if (ret)
196 return ret;
197
198 return es58x_rx_cmd_ret_u32(netdev, cmd_ret_type,
199 get_unaligned_le32(&es58x_fd_urb_cmd->rx_cmd_ret_le32));
200 }
201
es58x_fd_tx_ack_msg(struct net_device * netdev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd)202 static int es58x_fd_tx_ack_msg(struct net_device *netdev,
203 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
204 {
205 struct es58x_device *es58x_dev = es58x_priv(netdev)->es58x_dev;
206 const struct es58x_fd_tx_ack_msg *tx_ack_msg;
207 u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
208 int ret;
209
210 tx_ack_msg = &es58x_fd_urb_cmd->tx_ack_msg;
211 ret = es58x_check_msg_len(es58x_dev->dev, *tx_ack_msg, msg_len);
212 if (ret)
213 return ret;
214
215 return es58x_tx_ack_msg(netdev,
216 get_unaligned_le16(&tx_ack_msg->tx_free_entries),
217 get_unaligned_le32(&tx_ack_msg->rx_cmd_ret_le32));
218 }
219
es58x_fd_can_cmd_id(struct es58x_device * es58x_dev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd)220 static int es58x_fd_can_cmd_id(struct es58x_device *es58x_dev,
221 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
222 {
223 struct net_device *netdev;
224 int ret;
225
226 ret = es58x_get_netdev(es58x_dev, es58x_fd_urb_cmd->channel_idx,
227 ES58X_FD_CHANNEL_IDX_OFFSET, &netdev);
228 if (ret)
229 return ret;
230
231 switch ((enum es58x_fd_can_cmd_id)es58x_fd_urb_cmd->cmd_id) {
232 case ES58X_FD_CAN_CMD_ID_ENABLE_CHANNEL:
233 return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
234 ES58X_RET_TYPE_ENABLE_CHANNEL);
235
236 case ES58X_FD_CAN_CMD_ID_DISABLE_CHANNEL:
237 return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
238 ES58X_RET_TYPE_DISABLE_CHANNEL);
239
240 case ES58X_FD_CAN_CMD_ID_TX_MSG:
241 return es58x_fd_tx_ack_msg(netdev, es58x_fd_urb_cmd);
242
243 case ES58X_FD_CAN_CMD_ID_ECHO_MSG:
244 return es58x_fd_echo_msg(netdev, es58x_fd_urb_cmd);
245
246 case ES58X_FD_CAN_CMD_ID_RX_MSG:
247 return es58x_fd_rx_can_msg(netdev, es58x_fd_urb_cmd);
248
249 case ES58X_FD_CAN_CMD_ID_RESET_RX:
250 return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
251 ES58X_RET_TYPE_RESET_RX);
252
253 case ES58X_FD_CAN_CMD_ID_RESET_TX:
254 return es58x_fd_rx_cmd_ret_u32(netdev, es58x_fd_urb_cmd,
255 ES58X_RET_TYPE_RESET_TX);
256
257 case ES58X_FD_CAN_CMD_ID_ERROR_OR_EVENT_MSG:
258 return es58x_fd_rx_event_msg(netdev, es58x_fd_urb_cmd);
259
260 default:
261 return -EBADRQC;
262 }
263 }
264
es58x_fd_device_cmd_id(struct es58x_device * es58x_dev,const struct es58x_fd_urb_cmd * es58x_fd_urb_cmd)265 static int es58x_fd_device_cmd_id(struct es58x_device *es58x_dev,
266 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd)
267 {
268 u16 msg_len = get_unaligned_le16(&es58x_fd_urb_cmd->msg_len);
269 int ret;
270
271 switch ((enum es58x_fd_dev_cmd_id)es58x_fd_urb_cmd->cmd_id) {
272 case ES58X_FD_DEV_CMD_ID_TIMESTAMP:
273 ret = es58x_check_msg_len(es58x_dev->dev,
274 es58x_fd_urb_cmd->timestamp, msg_len);
275 if (ret)
276 return ret;
277 es58x_rx_timestamp(es58x_dev,
278 get_unaligned_le64(&es58x_fd_urb_cmd->timestamp));
279 return 0;
280
281 default:
282 return -EBADRQC;
283 }
284 }
285
es58x_fd_handle_urb_cmd(struct es58x_device * es58x_dev,const union es58x_urb_cmd * urb_cmd)286 static int es58x_fd_handle_urb_cmd(struct es58x_device *es58x_dev,
287 const union es58x_urb_cmd *urb_cmd)
288 {
289 const struct es58x_fd_urb_cmd *es58x_fd_urb_cmd;
290 int ret;
291
292 es58x_fd_urb_cmd = &urb_cmd->es58x_fd_urb_cmd;
293
294 switch ((enum es58x_fd_cmd_type)es58x_fd_urb_cmd->cmd_type) {
295 case ES58X_FD_CMD_TYPE_CAN:
296 case ES58X_FD_CMD_TYPE_CANFD:
297 ret = es58x_fd_can_cmd_id(es58x_dev, es58x_fd_urb_cmd);
298 break;
299
300 case ES58X_FD_CMD_TYPE_DEVICE:
301 ret = es58x_fd_device_cmd_id(es58x_dev, es58x_fd_urb_cmd);
302 break;
303
304 default:
305 ret = -EBADRQC;
306 break;
307 }
308
309 if (ret == -EBADRQC)
310 dev_err(es58x_dev->dev,
311 "%s: Unknown command type (0x%02X) and command ID (0x%02X) combination\n",
312 __func__, es58x_fd_urb_cmd->cmd_type,
313 es58x_fd_urb_cmd->cmd_id);
314
315 return ret;
316 }
317
es58x_fd_fill_urb_header(union es58x_urb_cmd * urb_cmd,u8 cmd_type,u8 cmd_id,u8 channel_idx,u16 msg_len)318 static void es58x_fd_fill_urb_header(union es58x_urb_cmd *urb_cmd, u8 cmd_type,
319 u8 cmd_id, u8 channel_idx, u16 msg_len)
320 {
321 struct es58x_fd_urb_cmd *es58x_fd_urb_cmd = &urb_cmd->es58x_fd_urb_cmd;
322
323 es58x_fd_urb_cmd->SOF = cpu_to_le16(es58x_fd_param.tx_start_of_frame);
324 es58x_fd_urb_cmd->cmd_type = cmd_type;
325 es58x_fd_urb_cmd->cmd_id = cmd_id;
326 es58x_fd_urb_cmd->channel_idx = channel_idx;
327 es58x_fd_urb_cmd->msg_len = cpu_to_le16(msg_len);
328 }
329
es58x_fd_tx_can_msg(struct es58x_priv * priv,const struct sk_buff * skb)330 static int es58x_fd_tx_can_msg(struct es58x_priv *priv,
331 const struct sk_buff *skb)
332 {
333 struct es58x_device *es58x_dev = priv->es58x_dev;
334 union es58x_urb_cmd *urb_cmd = priv->tx_urb->transfer_buffer;
335 struct es58x_fd_urb_cmd *es58x_fd_urb_cmd = &urb_cmd->es58x_fd_urb_cmd;
336 struct can_frame *cf = (struct can_frame *)skb->data;
337 struct es58x_fd_tx_can_msg *tx_can_msg;
338 bool is_fd = can_is_canfd_skb(skb);
339 u16 msg_len;
340 int ret;
341
342 if (priv->tx_can_msg_cnt == 0) {
343 msg_len = 0;
344 es58x_fd_fill_urb_header(urb_cmd,
345 is_fd ? ES58X_FD_CMD_TYPE_CANFD
346 : ES58X_FD_CMD_TYPE_CAN,
347 ES58X_FD_CAN_CMD_ID_TX_MSG_NO_ACK,
348 priv->channel_idx, msg_len);
349 } else {
350 msg_len = es58x_fd_get_msg_len(urb_cmd);
351 }
352
353 ret = es58x_check_msg_max_len(es58x_dev->dev,
354 es58x_fd_urb_cmd->tx_can_msg_buf,
355 msg_len + sizeof(*tx_can_msg));
356 if (ret)
357 return ret;
358
359 /* Fill message contents. */
360 tx_can_msg = (typeof(tx_can_msg))&es58x_fd_urb_cmd->raw_msg[msg_len];
361 tx_can_msg->packet_idx = (u8)priv->tx_head;
362 put_unaligned_le32(es58x_get_raw_can_id(cf), &tx_can_msg->can_id);
363 tx_can_msg->flags = (u8)es58x_get_flags(skb);
364 if (is_fd)
365 tx_can_msg->len = cf->len;
366 else
367 tx_can_msg->dlc = can_get_cc_dlc(cf, priv->can.ctrlmode);
368 memcpy(tx_can_msg->data, cf->data, cf->len);
369
370 /* Calculate new sizes */
371 msg_len += es58x_fd_sizeof_rx_tx_msg(*tx_can_msg);
372 priv->tx_urb->transfer_buffer_length = es58x_get_urb_cmd_len(es58x_dev,
373 msg_len);
374 put_unaligned_le16(msg_len, &es58x_fd_urb_cmd->msg_len);
375
376 return 0;
377 }
378
es58x_fd_convert_bittiming(struct es58x_fd_bittiming * es58x_fd_bt,struct can_bittiming * bt)379 static void es58x_fd_convert_bittiming(struct es58x_fd_bittiming *es58x_fd_bt,
380 struct can_bittiming *bt)
381 {
382 /* The actual value set in the hardware registers is one less
383 * than the functional value.
384 */
385 const int offset = 1;
386
387 es58x_fd_bt->bitrate = cpu_to_le32(bt->bitrate);
388 es58x_fd_bt->tseg1 =
389 cpu_to_le16(bt->prop_seg + bt->phase_seg1 - offset);
390 es58x_fd_bt->tseg2 = cpu_to_le16(bt->phase_seg2 - offset);
391 es58x_fd_bt->brp = cpu_to_le16(bt->brp - offset);
392 es58x_fd_bt->sjw = cpu_to_le16(bt->sjw - offset);
393 }
394
es58x_fd_enable_channel(struct es58x_priv * priv)395 static int es58x_fd_enable_channel(struct es58x_priv *priv)
396 {
397 struct es58x_device *es58x_dev = priv->es58x_dev;
398 struct net_device *netdev = es58x_dev->netdev[priv->channel_idx];
399 struct es58x_fd_tx_conf_msg tx_conf_msg = { 0 };
400 u32 ctrlmode;
401 size_t conf_len = 0;
402
403 es58x_fd_convert_bittiming(&tx_conf_msg.nominal_bittiming,
404 &priv->can.bittiming);
405 ctrlmode = priv->can.ctrlmode;
406
407 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES)
408 tx_conf_msg.samples_per_bit = ES58X_SAMPLES_PER_BIT_THREE;
409 else
410 tx_conf_msg.samples_per_bit = ES58X_SAMPLES_PER_BIT_ONE;
411 tx_conf_msg.sync_edge = ES58X_SYNC_EDGE_SINGLE;
412 tx_conf_msg.physical_layer = ES58X_PHYSICAL_LAYER_HIGH_SPEED;
413 tx_conf_msg.echo_mode = ES58X_ECHO_ON;
414 if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
415 tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_PASSIVE;
416 else
417 tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_ACTIVE;
418
419 if (ctrlmode & CAN_CTRLMODE_FD_NON_ISO) {
420 tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_FD_NON_ISO;
421 tx_conf_msg.canfd_enabled = 1;
422 } else if (ctrlmode & CAN_CTRLMODE_FD) {
423 tx_conf_msg.ctrlmode |= ES58X_FD_CTRLMODE_FD;
424 tx_conf_msg.canfd_enabled = 1;
425 }
426
427 if (tx_conf_msg.canfd_enabled) {
428 es58x_fd_convert_bittiming(&tx_conf_msg.data_bittiming,
429 &priv->can.data_bittiming);
430
431 if (priv->can.tdc.tdco) {
432 tx_conf_msg.tdc_enabled = 1;
433 tx_conf_msg.tdco = cpu_to_le16(priv->can.tdc.tdco);
434 tx_conf_msg.tdcf = cpu_to_le16(priv->can.tdc.tdcf);
435 }
436
437 conf_len = ES58X_FD_CANFD_CONF_LEN;
438 } else {
439 conf_len = ES58X_FD_CAN_CONF_LEN;
440 }
441
442 return es58x_send_msg(es58x_dev, es58x_fd_cmd_type(netdev),
443 ES58X_FD_CAN_CMD_ID_ENABLE_CHANNEL,
444 &tx_conf_msg, conf_len, priv->channel_idx);
445 }
446
es58x_fd_disable_channel(struct es58x_priv * priv)447 static int es58x_fd_disable_channel(struct es58x_priv *priv)
448 {
449 /* The type (ES58X_FD_CMD_TYPE_CAN or ES58X_FD_CMD_TYPE_CANFD) does
450 * not matter here.
451 */
452 return es58x_send_msg(priv->es58x_dev, ES58X_FD_CMD_TYPE_CAN,
453 ES58X_FD_CAN_CMD_ID_DISABLE_CHANNEL,
454 ES58X_EMPTY_MSG, 0, priv->channel_idx);
455 }
456
es58x_fd_get_timestamp(struct es58x_device * es58x_dev)457 static int es58x_fd_get_timestamp(struct es58x_device *es58x_dev)
458 {
459 return es58x_send_msg(es58x_dev, ES58X_FD_CMD_TYPE_DEVICE,
460 ES58X_FD_DEV_CMD_ID_TIMESTAMP, ES58X_EMPTY_MSG,
461 0, ES58X_CHANNEL_IDX_NA);
462 }
463
464 /* Nominal bittiming constants for ES582.1 and ES584.1 as specified in
465 * the microcontroller datasheet: "SAM E70/S70/V70/V71 Family" section
466 * 49.6.8 "MCAN Nominal Bit Timing and Prescaler Register" from
467 * Microchip.
468 *
469 * The values from the specification are the hardware register
470 * values. To convert them to the functional values, all ranges were
471 * incremented by 1 (e.g. range [0..n-1] changed to [1..n]).
472 */
473 static const struct can_bittiming_const es58x_fd_nom_bittiming_const = {
474 .name = "ES582.1/ES584.1",
475 .tseg1_min = 2,
476 .tseg1_max = 256,
477 .tseg2_min = 2,
478 .tseg2_max = 128,
479 .sjw_max = 128,
480 .brp_min = 1,
481 .brp_max = 512,
482 .brp_inc = 1
483 };
484
485 /* Data bittiming constants for ES582.1 and ES584.1 as specified in
486 * the microcontroller datasheet: "SAM E70/S70/V70/V71 Family" section
487 * 49.6.4 "MCAN Data Bit Timing and Prescaler Register" from
488 * Microchip.
489 */
490 static const struct can_bittiming_const es58x_fd_data_bittiming_const = {
491 .name = "ES582.1/ES584.1",
492 .tseg1_min = 2,
493 .tseg1_max = 32,
494 .tseg2_min = 1,
495 .tseg2_max = 16,
496 .sjw_max = 8,
497 .brp_min = 1,
498 .brp_max = 32,
499 .brp_inc = 1
500 };
501
502 /* Transmission Delay Compensation constants for ES582.1 and ES584.1
503 * as specified in the microcontroller datasheet: "SAM E70/S70/V70/V71
504 * Family" section 49.6.15 "MCAN Transmitter Delay Compensation
505 * Register" from Microchip.
506 */
507 static const struct can_tdc_const es58x_tdc_const = {
508 .tdcv_max = 0, /* Manual mode not supported. */
509 .tdco_max = 127,
510 .tdcf_max = 127
511 };
512
513 const struct es58x_parameters es58x_fd_param = {
514 .bittiming_const = &es58x_fd_nom_bittiming_const,
515 .data_bittiming_const = &es58x_fd_data_bittiming_const,
516 .tdc_const = &es58x_tdc_const,
517 /* The devices use NXP TJA1044G transievers which guarantee
518 * the timing for data rates up to 5 Mbps. Bitrates up to 8
519 * Mbps work in an optimal environment but are not recommended
520 * for production environment.
521 */
522 .bitrate_max = 8 * CAN_MBPS,
523 .clock = {.freq = 80 * CAN_MHZ},
524 .ctrlmode_supported = CAN_CTRLMODE_LOOPBACK | CAN_CTRLMODE_LISTENONLY |
525 CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_FD | CAN_CTRLMODE_FD_NON_ISO |
526 CAN_CTRLMODE_CC_LEN8_DLC,
527 .tx_start_of_frame = 0xCEFA, /* FACE in little endian */
528 .rx_start_of_frame = 0xFECA, /* CAFE in little endian */
529 .tx_urb_cmd_max_len = ES58X_FD_TX_URB_CMD_MAX_LEN,
530 .rx_urb_cmd_max_len = ES58X_FD_RX_URB_CMD_MAX_LEN,
531 /* Size of internal device TX queue is 500.
532 *
533 * However, when reaching value around 278, the device's busy
534 * LED turns on and thus maximum value of 500 is never reached
535 * in practice. Also, when this value is too high, some error
536 * on the echo_msg were witnessed when the device is
537 * recovering from bus off.
538 *
539 * For above reasons, a value that would prevent the device
540 * from becoming busy was chosen. In practice, BQL would
541 * prevent the value from even getting closer to below
542 * maximum, so no impact on performance was measured.
543 */
544 .fifo_mask = 255, /* echo_skb_max = 256 */
545 .dql_min_limit = CAN_FRAME_LEN_MAX * 15, /* Empirical value. */
546 .tx_bulk_max = ES58X_FD_TX_BULK_MAX,
547 .urb_cmd_header_len = ES58X_FD_URB_CMD_HEADER_LEN,
548 .rx_urb_max = ES58X_RX_URBS_MAX,
549 .tx_urb_max = ES58X_TX_URBS_MAX
550 };
551
552 const struct es58x_operators es58x_fd_ops = {
553 .get_msg_len = es58x_fd_get_msg_len,
554 .handle_urb_cmd = es58x_fd_handle_urb_cmd,
555 .fill_urb_header = es58x_fd_fill_urb_header,
556 .tx_can_msg = es58x_fd_tx_can_msg,
557 .enable_channel = es58x_fd_enable_channel,
558 .disable_channel = es58x_fd_disable_channel,
559 .reset_device = NULL, /* Not implemented in the device firmware. */
560 .get_timestamp = es58x_fd_get_timestamp
561 };
562
