xref: /linux/drivers/net/can/usb/esd_usb.c (revision abacaf559950eec0d99d37ff6b92049409af5943)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * CAN driver for esd electronics gmbh CAN-USB/2, CAN-USB/3 and CAN-USB/Micro
4  *
5  * Copyright (C) 2010-2012 esd electronic system design gmbh, Matthias Fuchs <socketcan@esd.eu>
6  * Copyright (C) 2022-2024 esd electronics gmbh, Frank Jungclaus <frank.jungclaus@esd.eu>
7  */
8 
9 #include <linux/can.h>
10 #include <linux/can/dev.h>
11 #include <linux/can/error.h>
12 #include <linux/err.h>
13 #include <linux/ethtool.h>
14 #include <linux/module.h>
15 #include <linux/netdevice.h>
16 #include <linux/signal.h>
17 #include <linux/slab.h>
18 #include <linux/units.h>
19 #include <linux/usb.h>
20 
21 MODULE_AUTHOR("Matthias Fuchs <socketcan@esd.eu>");
22 MODULE_AUTHOR("Frank Jungclaus <frank.jungclaus@esd.eu>");
23 MODULE_DESCRIPTION("CAN driver for esd electronics gmbh CAN-USB/2, CAN-USB/3 and CAN-USB/Micro interfaces");
24 MODULE_LICENSE("GPL v2");
25 
26 /* USB vendor and product ID */
27 #define ESD_USB_ESDGMBH_VENDOR_ID	0x0ab4
28 #define ESD_USB_CANUSB2_PRODUCT_ID	0x0010
29 #define ESD_USB_CANUSBM_PRODUCT_ID	0x0011
30 #define ESD_USB_CANUSB3_PRODUCT_ID	0x0014
31 
32 /* CAN controller clock frequencies */
33 #define ESD_USB_2_CAN_CLOCK	(60 * MEGA) /* Hz */
34 #define ESD_USB_M_CAN_CLOCK	(36 * MEGA) /* Hz */
35 #define ESD_USB_3_CAN_CLOCK	(80 * MEGA) /* Hz */
36 
37 /* Maximum number of CAN nets */
38 #define ESD_USB_MAX_NETS	2
39 
40 /* USB commands */
41 #define ESD_USB_CMD_VERSION		1 /* also used for VERSION_REPLY */
42 #define ESD_USB_CMD_CAN_RX		2 /* device to host only */
43 #define ESD_USB_CMD_CAN_TX		3 /* also used for TX_DONE */
44 #define ESD_USB_CMD_SETBAUD		4 /* also used for SETBAUD_REPLY */
45 #define ESD_USB_CMD_TS			5 /* also used for TS_REPLY */
46 #define ESD_USB_CMD_IDADD		6 /* also used for IDADD_REPLY */
47 
48 /* esd CAN message flags - dlc field */
49 #define ESD_USB_RTR	BIT(4)
50 #define ESD_USB_NO_BRS	BIT(4)
51 #define ESD_USB_ESI	BIT(5)
52 #define ESD_USB_FD	BIT(7)
53 
54 /* esd CAN message flags - id field */
55 #define ESD_USB_EXTID	BIT(29)
56 #define ESD_USB_EVENT	BIT(30)
57 #define ESD_USB_IDMASK	GENMASK(28, 0)
58 
59 /* esd CAN event ids */
60 #define ESD_USB_EV_CAN_ERROR_EXT	2 /* CAN controller specific diagnostic data */
61 
62 /* baudrate message flags */
63 #define ESD_USB_LOM	BIT(30) /* Listen Only Mode */
64 #define ESD_USB_UBR	BIT(31) /* User Bit Rate (controller BTR) in bits 0..27 */
65 #define ESD_USB_NO_BAUDRATE	GENMASK(30, 0) /* bit rate unconfigured */
66 
67 /* bit timing esd CAN-USB */
68 #define ESD_USB_2_TSEG1_SHIFT	16
69 #define ESD_USB_2_TSEG2_SHIFT	20
70 #define ESD_USB_2_SJW_SHIFT	14
71 #define ESD_USB_M_SJW_SHIFT	24
72 #define ESD_USB_TRIPLE_SAMPLES	BIT(23)
73 
74 /* Transmitter Delay Compensation */
75 #define ESD_USB_3_TDC_MODE_AUTO	0
76 
77 /* esd IDADD message */
78 #define ESD_USB_ID_ENABLE	BIT(7)
79 #define ESD_USB_MAX_ID_SEGMENT	64
80 
81 /* SJA1000 ECC register (emulated by usb firmware) */
82 #define ESD_USB_SJA1000_ECC_SEG		GENMASK(4, 0)
83 #define ESD_USB_SJA1000_ECC_DIR		BIT(5)
84 #define ESD_USB_SJA1000_ECC_ERR		BIT(2, 1)
85 #define ESD_USB_SJA1000_ECC_BIT		0x00
86 #define ESD_USB_SJA1000_ECC_FORM	BIT(6)
87 #define ESD_USB_SJA1000_ECC_STUFF	BIT(7)
88 #define ESD_USB_SJA1000_ECC_MASK	GENMASK(7, 6)
89 
90 /* esd bus state event codes */
91 #define ESD_USB_BUSSTATE_MASK	GENMASK(7, 6)
92 #define ESD_USB_BUSSTATE_WARN	BIT(6)
93 #define ESD_USB_BUSSTATE_ERRPASSIVE	BIT(7)
94 #define ESD_USB_BUSSTATE_BUSOFF	GENMASK(7, 6)
95 
96 #define ESD_USB_RX_BUFFER_SIZE		1024
97 #define ESD_USB_MAX_RX_URBS		4
98 #define ESD_USB_MAX_TX_URBS		16 /* must be power of 2 */
99 
100 /* Modes for CAN-USB/3, to be used for esd_usb_3_set_baudrate_msg_x.mode */
101 #define ESD_USB_3_BAUDRATE_MODE_DISABLE		0 /* remove from bus */
102 #define ESD_USB_3_BAUDRATE_MODE_INDEX		1 /* ESD (CiA) bit rate idx */
103 #define ESD_USB_3_BAUDRATE_MODE_BTR_CTRL	2 /* BTR values (controller)*/
104 #define ESD_USB_3_BAUDRATE_MODE_BTR_CANONICAL	3 /* BTR values (canonical) */
105 #define ESD_USB_3_BAUDRATE_MODE_NUM		4 /* numerical bit rate */
106 #define ESD_USB_3_BAUDRATE_MODE_AUTOBAUD	5 /* autobaud */
107 
108 /* Flags for CAN-USB/3, to be used for esd_usb_3_set_baudrate_msg_x.flags */
109 #define ESD_USB_3_BAUDRATE_FLAG_FD	BIT(0) /* enable CAN FD mode */
110 #define ESD_USB_3_BAUDRATE_FLAG_LOM	BIT(1) /* enable listen only mode */
111 #define ESD_USB_3_BAUDRATE_FLAG_STM	BIT(2) /* enable self test mode */
112 #define ESD_USB_3_BAUDRATE_FLAG_TRS	BIT(3) /* enable triple sampling */
113 #define ESD_USB_3_BAUDRATE_FLAG_TXP	BIT(4) /* enable transmit pause */
114 
115 struct esd_usb_header_msg {
116 	u8 len; /* total message length in 32bit words */
117 	u8 cmd;
118 	u8 rsvd[2];
119 };
120 
121 struct esd_usb_version_msg {
122 	u8 len; /* total message length in 32bit words */
123 	u8 cmd;
124 	u8 rsvd;
125 	u8 flags;
126 	__le32 drv_version;
127 };
128 
129 struct esd_usb_version_reply_msg {
130 	u8 len; /* total message length in 32bit words */
131 	u8 cmd;
132 	u8 nets;
133 	u8 features;
134 	__le32 version;
135 	u8 name[16];
136 	__le32 rsvd;
137 	__le32 ts;
138 };
139 
140 struct esd_usb_rx_msg {
141 	u8 len; /* total message length in 32bit words */
142 	u8 cmd;
143 	u8 net;
144 	u8 dlc;
145 	__le32 ts;
146 	__le32 id; /* upper 3 bits contain flags */
147 	union {
148 		u8 data[CAN_MAX_DLEN];
149 		u8 data_fd[CANFD_MAX_DLEN];
150 		struct {
151 			u8 status; /* CAN Controller Status */
152 			u8 ecc;    /* Error Capture Register */
153 			u8 rec;    /* RX Error Counter */
154 			u8 tec;    /* TX Error Counter */
155 		} ev_can_err_ext;  /* For ESD_EV_CAN_ERROR_EXT */
156 	};
157 };
158 
159 struct esd_usb_tx_msg {
160 	u8 len; /* total message length in 32bit words */
161 	u8 cmd;
162 	u8 net;
163 	u8 dlc;
164 	u32 hnd;	/* opaque handle, not used by device */
165 	__le32 id; /* upper 3 bits contain flags */
166 	union {
167 		u8 data[CAN_MAX_DLEN];
168 		u8 data_fd[CANFD_MAX_DLEN];
169 	};
170 };
171 
172 struct esd_usb_tx_done_msg {
173 	u8 len; /* total message length in 32bit words */
174 	u8 cmd;
175 	u8 net;
176 	u8 status;
177 	u32 hnd;	/* opaque handle, not used by device */
178 	__le32 ts;
179 };
180 
181 struct esd_usb_id_filter_msg {
182 	u8 len; /* total message length in 32bit words */
183 	u8 cmd;
184 	u8 net;
185 	u8 option;
186 	__le32 mask[ESD_USB_MAX_ID_SEGMENT + 1]; /* +1 for 29bit extended IDs */
187 };
188 
189 struct esd_usb_set_baudrate_msg {
190 	u8 len; /* total message length in 32bit words */
191 	u8 cmd;
192 	u8 net;
193 	u8 rsvd;
194 	__le32 baud;
195 };
196 
197 /* CAN-USB/3 baudrate configuration, used for nominal as well as for data bit rate */
198 struct esd_usb_3_baudrate_cfg {
199 	__le16 brp;	/* bit rate pre-scaler */
200 	__le16 tseg1;	/* time segment before sample point */
201 	__le16 tseg2;	/* time segment after sample point */
202 	__le16 sjw;	/* synchronization jump Width */
203 };
204 
205 /* In principle, the esd CAN-USB/3 supports Transmitter Delay Compensation (TDC),
206  * but currently only the automatic TDC mode is supported by this driver.
207  * An implementation for manual TDC configuration will follow.
208  *
209  * For information about struct esd_usb_3_tdc_cfg, see
210  * NTCAN Application Developers Manual, 6.2.25 NTCAN_TDC_CFG + related chapters
211  * https://esd.eu/fileadmin/esd/docs/manuals/NTCAN_Part1_Function_API_Manual_en_56.pdf
212  */
213 struct esd_usb_3_tdc_cfg {
214 	u8 tdc_mode;	/* transmitter delay compensation mode  */
215 	u8 ssp_offset;	/* secondary sample point offset in mtq */
216 	s8 ssp_shift;	/* secondary sample point shift in mtq */
217 	u8 tdc_filter;	/* TDC filter in mtq */
218 };
219 
220 /* Extended version of the above set_baudrate_msg for a CAN-USB/3
221  * to define the CAN bit timing configuration of the CAN controller in
222  * CAN FD mode as well as in Classical CAN mode.
223  *
224  * The payload of this command is a NTCAN_BAUDRATE_X structure according to
225  * esd electronics gmbh, NTCAN Application Developers Manual, 6.2.15 NTCAN_BAUDRATE_X
226  * https://esd.eu/fileadmin/esd/docs/manuals/NTCAN_Part1_Function_API_Manual_en_56.pdf
227  */
228 struct esd_usb_3_set_baudrate_msg_x {
229 	u8 len;	/* total message length in 32bit words */
230 	u8 cmd;
231 	u8 net;
232 	u8 rsvd;	/*reserved */
233 	/* Payload ... */
234 	__le16 mode;	/* mode word, see ESD_USB_3_BAUDRATE_MODE_xxx */
235 	__le16 flags;	/* control flags, see ESD_USB_3_BAUDRATE_FLAG_xxx */
236 	struct esd_usb_3_tdc_cfg tdc;	/* TDC configuration */
237 	struct esd_usb_3_baudrate_cfg nom;	/* nominal bit rate */
238 	struct esd_usb_3_baudrate_cfg data;	/* data bit rate */
239 };
240 
241 /* Main message type used between library and application */
242 union __packed esd_usb_msg {
243 	struct esd_usb_header_msg hdr;
244 	struct esd_usb_version_msg version;
245 	struct esd_usb_version_reply_msg version_reply;
246 	struct esd_usb_rx_msg rx;
247 	struct esd_usb_tx_msg tx;
248 	struct esd_usb_tx_done_msg txdone;
249 	struct esd_usb_set_baudrate_msg setbaud;
250 	struct esd_usb_3_set_baudrate_msg_x setbaud_x;
251 	struct esd_usb_id_filter_msg filter;
252 };
253 
254 static struct usb_device_id esd_usb_table[] = {
255 	{USB_DEVICE(ESD_USB_ESDGMBH_VENDOR_ID, ESD_USB_CANUSB2_PRODUCT_ID)},
256 	{USB_DEVICE(ESD_USB_ESDGMBH_VENDOR_ID, ESD_USB_CANUSBM_PRODUCT_ID)},
257 	{USB_DEVICE(ESD_USB_ESDGMBH_VENDOR_ID, ESD_USB_CANUSB3_PRODUCT_ID)},
258 	{}
259 };
260 MODULE_DEVICE_TABLE(usb, esd_usb_table);
261 
262 struct esd_usb_net_priv;
263 
264 struct esd_tx_urb_context {
265 	struct esd_usb_net_priv *priv;
266 	u32 echo_index;
267 };
268 
269 struct esd_usb {
270 	struct usb_device *udev;
271 	struct esd_usb_net_priv *nets[ESD_USB_MAX_NETS];
272 
273 	struct usb_anchor rx_submitted;
274 
275 	unsigned int rx_pipe;
276 	unsigned int tx_pipe;
277 
278 	int net_count;
279 	u32 version;
280 	int rxinitdone;
281 	int in_usb_disconnect;
282 	void *rxbuf[ESD_USB_MAX_RX_URBS];
283 	dma_addr_t rxbuf_dma[ESD_USB_MAX_RX_URBS];
284 };
285 
286 struct esd_usb_net_priv {
287 	struct can_priv can; /* must be the first member */
288 
289 	atomic_t active_tx_jobs;
290 	struct usb_anchor tx_submitted;
291 	struct esd_tx_urb_context tx_contexts[ESD_USB_MAX_TX_URBS];
292 
293 	struct esd_usb *usb;
294 	struct net_device *netdev;
295 	int index;
296 	u8 old_state;
297 	struct can_berr_counter bec;
298 };
299 
esd_usb_rx_event(struct esd_usb_net_priv * priv,union esd_usb_msg * msg)300 static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
301 			     union esd_usb_msg *msg)
302 {
303 	struct net_device_stats *stats = &priv->netdev->stats;
304 	struct can_frame *cf;
305 	struct sk_buff *skb;
306 	u32 id = le32_to_cpu(msg->rx.id) & ESD_USB_IDMASK;
307 
308 	if (id == ESD_USB_EV_CAN_ERROR_EXT) {
309 		u8 state = msg->rx.ev_can_err_ext.status;
310 		u8 ecc = msg->rx.ev_can_err_ext.ecc;
311 
312 		priv->bec.rxerr = msg->rx.ev_can_err_ext.rec;
313 		priv->bec.txerr = msg->rx.ev_can_err_ext.tec;
314 
315 		netdev_dbg(priv->netdev,
316 			   "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
317 			   msg->rx.dlc, state, ecc,
318 			   priv->bec.rxerr, priv->bec.txerr);
319 
320 		/* if berr-reporting is off, only pass through on state change ... */
321 		if (!(priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
322 		    state == priv->old_state)
323 			return;
324 
325 		skb = alloc_can_err_skb(priv->netdev, &cf);
326 		if (!skb)
327 			stats->rx_dropped++;
328 
329 		if (state != priv->old_state) {
330 			enum can_state tx_state, rx_state;
331 			enum can_state new_state = CAN_STATE_ERROR_ACTIVE;
332 
333 			priv->old_state = state;
334 
335 			switch (state & ESD_USB_BUSSTATE_MASK) {
336 			case ESD_USB_BUSSTATE_BUSOFF:
337 				new_state = CAN_STATE_BUS_OFF;
338 				can_bus_off(priv->netdev);
339 				break;
340 			case ESD_USB_BUSSTATE_WARN:
341 				new_state = CAN_STATE_ERROR_WARNING;
342 				break;
343 			case ESD_USB_BUSSTATE_ERRPASSIVE:
344 				new_state = CAN_STATE_ERROR_PASSIVE;
345 				break;
346 			default:
347 				new_state = CAN_STATE_ERROR_ACTIVE;
348 				priv->bec.txerr = 0;
349 				priv->bec.rxerr = 0;
350 				break;
351 			}
352 
353 			if (new_state != priv->can.state) {
354 				tx_state = (priv->bec.txerr >= priv->bec.rxerr) ? new_state : 0;
355 				rx_state = (priv->bec.txerr <= priv->bec.rxerr) ? new_state : 0;
356 				can_change_state(priv->netdev, cf,
357 						 tx_state, rx_state);
358 			}
359 		} else if (skb) {
360 			priv->can.can_stats.bus_error++;
361 			stats->rx_errors++;
362 
363 			cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
364 
365 			switch (ecc & ESD_USB_SJA1000_ECC_MASK) {
366 			case ESD_USB_SJA1000_ECC_BIT:
367 				cf->data[2] |= CAN_ERR_PROT_BIT;
368 				break;
369 			case ESD_USB_SJA1000_ECC_FORM:
370 				cf->data[2] |= CAN_ERR_PROT_FORM;
371 				break;
372 			case ESD_USB_SJA1000_ECC_STUFF:
373 				cf->data[2] |= CAN_ERR_PROT_STUFF;
374 				break;
375 			default:
376 				break;
377 			}
378 
379 			/* Error occurred during transmission? */
380 			if (!(ecc & ESD_USB_SJA1000_ECC_DIR))
381 				cf->data[2] |= CAN_ERR_PROT_TX;
382 
383 			/* Bit stream position in CAN frame as the error was detected */
384 			cf->data[3] = ecc & ESD_USB_SJA1000_ECC_SEG;
385 		}
386 
387 		if (skb) {
388 			cf->can_id |= CAN_ERR_CNT;
389 			cf->data[6] = priv->bec.txerr;
390 			cf->data[7] = priv->bec.rxerr;
391 
392 			netif_rx(skb);
393 		}
394 	}
395 }
396 
esd_usb_rx_can_msg(struct esd_usb_net_priv * priv,union esd_usb_msg * msg)397 static void esd_usb_rx_can_msg(struct esd_usb_net_priv *priv,
398 			       union esd_usb_msg *msg)
399 {
400 	struct net_device_stats *stats = &priv->netdev->stats;
401 	struct can_frame *cf;
402 	struct canfd_frame *cfd;
403 	struct sk_buff *skb;
404 	u32 id;
405 	u8 len;
406 
407 	if (!netif_device_present(priv->netdev))
408 		return;
409 
410 	id = le32_to_cpu(msg->rx.id);
411 
412 	if (id & ESD_USB_EVENT) {
413 		esd_usb_rx_event(priv, msg);
414 	} else {
415 		if (msg->rx.dlc & ESD_USB_FD) {
416 			skb = alloc_canfd_skb(priv->netdev, &cfd);
417 		} else {
418 			skb = alloc_can_skb(priv->netdev, &cf);
419 			cfd = (struct canfd_frame *)cf;
420 		}
421 
422 		if (skb == NULL) {
423 			stats->rx_dropped++;
424 			return;
425 		}
426 
427 		cfd->can_id = id & ESD_USB_IDMASK;
428 
429 		if (msg->rx.dlc & ESD_USB_FD) {
430 			/* masking by 0x0F is already done within can_fd_dlc2len() */
431 			cfd->len = can_fd_dlc2len(msg->rx.dlc);
432 			len = cfd->len;
433 			if ((msg->rx.dlc & ESD_USB_NO_BRS) == 0)
434 				cfd->flags |= CANFD_BRS;
435 			if (msg->rx.dlc & ESD_USB_ESI)
436 				cfd->flags |= CANFD_ESI;
437 		} else {
438 			can_frame_set_cc_len(cf, msg->rx.dlc & ~ESD_USB_RTR, priv->can.ctrlmode);
439 			len = cf->len;
440 			if (msg->rx.dlc & ESD_USB_RTR) {
441 				cf->can_id |= CAN_RTR_FLAG;
442 				len = 0;
443 			}
444 		}
445 
446 		if (id & ESD_USB_EXTID)
447 			cfd->can_id |= CAN_EFF_FLAG;
448 
449 		memcpy(cfd->data, msg->rx.data_fd, len);
450 		stats->rx_bytes += len;
451 		stats->rx_packets++;
452 
453 		netif_rx(skb);
454 	}
455 }
456 
esd_usb_tx_done_msg(struct esd_usb_net_priv * priv,union esd_usb_msg * msg)457 static void esd_usb_tx_done_msg(struct esd_usb_net_priv *priv,
458 				union esd_usb_msg *msg)
459 {
460 	struct net_device_stats *stats = &priv->netdev->stats;
461 	struct net_device *netdev = priv->netdev;
462 	struct esd_tx_urb_context *context;
463 
464 	if (!netif_device_present(netdev))
465 		return;
466 
467 	context = &priv->tx_contexts[msg->txdone.hnd & (ESD_USB_MAX_TX_URBS - 1)];
468 
469 	if (!msg->txdone.status) {
470 		stats->tx_packets++;
471 		stats->tx_bytes += can_get_echo_skb(netdev, context->echo_index,
472 						    NULL);
473 	} else {
474 		stats->tx_errors++;
475 		can_free_echo_skb(netdev, context->echo_index, NULL);
476 	}
477 
478 	/* Release context */
479 	context->echo_index = ESD_USB_MAX_TX_URBS;
480 	atomic_dec(&priv->active_tx_jobs);
481 
482 	netif_wake_queue(netdev);
483 }
484 
esd_usb_read_bulk_callback(struct urb * urb)485 static void esd_usb_read_bulk_callback(struct urb *urb)
486 {
487 	struct esd_usb *dev = urb->context;
488 	int err;
489 	int pos = 0;
490 	int i;
491 
492 	switch (urb->status) {
493 	case 0: /* success */
494 		break;
495 
496 	case -ENOENT:
497 	case -EPIPE:
498 	case -EPROTO:
499 	case -ESHUTDOWN:
500 		return;
501 
502 	default:
503 		dev_info(dev->udev->dev.parent,
504 			 "Rx URB aborted (%pe)\n", ERR_PTR(urb->status));
505 		goto resubmit_urb;
506 	}
507 
508 	while (pos < urb->actual_length) {
509 		union esd_usb_msg *msg;
510 
511 		msg = (union esd_usb_msg *)(urb->transfer_buffer + pos);
512 
513 		switch (msg->hdr.cmd) {
514 		case ESD_USB_CMD_CAN_RX:
515 			if (msg->rx.net >= dev->net_count) {
516 				dev_err(dev->udev->dev.parent, "format error\n");
517 				break;
518 			}
519 
520 			esd_usb_rx_can_msg(dev->nets[msg->rx.net], msg);
521 			break;
522 
523 		case ESD_USB_CMD_CAN_TX:
524 			if (msg->txdone.net >= dev->net_count) {
525 				dev_err(dev->udev->dev.parent, "format error\n");
526 				break;
527 			}
528 
529 			esd_usb_tx_done_msg(dev->nets[msg->txdone.net],
530 					    msg);
531 			break;
532 		}
533 
534 		pos += msg->hdr.len * sizeof(u32); /* convert to # of bytes */
535 
536 		if (pos > urb->actual_length) {
537 			dev_err(dev->udev->dev.parent, "format error\n");
538 			break;
539 		}
540 	}
541 
542 resubmit_urb:
543 	usb_fill_bulk_urb(urb, dev->udev, dev->rx_pipe,
544 			  urb->transfer_buffer, ESD_USB_RX_BUFFER_SIZE,
545 			  esd_usb_read_bulk_callback, dev);
546 
547 	usb_anchor_urb(urb, &dev->rx_submitted);
548 
549 	err = usb_submit_urb(urb, GFP_ATOMIC);
550 	if (!err)
551 		return;
552 
553 	usb_unanchor_urb(urb);
554 
555 	if (err == -ENODEV) {
556 		for (i = 0; i < dev->net_count; i++) {
557 			if (dev->nets[i])
558 				netif_device_detach(dev->nets[i]->netdev);
559 		}
560 	} else {
561 		dev_err(dev->udev->dev.parent,
562 			"failed resubmitting read bulk urb: %pe\n", ERR_PTR(err));
563 	}
564 }
565 
566 /* callback for bulk IN urb */
esd_usb_write_bulk_callback(struct urb * urb)567 static void esd_usb_write_bulk_callback(struct urb *urb)
568 {
569 	struct esd_tx_urb_context *context = urb->context;
570 	struct esd_usb_net_priv *priv;
571 	struct net_device *netdev;
572 	size_t size = sizeof(union esd_usb_msg);
573 
574 	WARN_ON(!context);
575 
576 	priv = context->priv;
577 	netdev = priv->netdev;
578 
579 	/* free up our allocated buffer */
580 	usb_free_coherent(urb->dev, size,
581 			  urb->transfer_buffer, urb->transfer_dma);
582 
583 	if (!netif_device_present(netdev))
584 		return;
585 
586 	if (urb->status)
587 		netdev_info(netdev, "Tx URB aborted (%pe)\n", ERR_PTR(urb->status));
588 
589 	netif_trans_update(netdev);
590 }
591 
firmware_show(struct device * d,struct device_attribute * attr,char * buf)592 static ssize_t firmware_show(struct device *d,
593 			     struct device_attribute *attr, char *buf)
594 {
595 	struct usb_interface *intf = to_usb_interface(d);
596 	struct esd_usb *dev = usb_get_intfdata(intf);
597 
598 	return sprintf(buf, "%d.%d.%d\n",
599 		       (dev->version >> 12) & 0xf,
600 		       (dev->version >> 8) & 0xf,
601 		       dev->version & 0xff);
602 }
603 static DEVICE_ATTR_RO(firmware);
604 
hardware_show(struct device * d,struct device_attribute * attr,char * buf)605 static ssize_t hardware_show(struct device *d,
606 			     struct device_attribute *attr, char *buf)
607 {
608 	struct usb_interface *intf = to_usb_interface(d);
609 	struct esd_usb *dev = usb_get_intfdata(intf);
610 
611 	return sprintf(buf, "%d.%d.%d\n",
612 		       (dev->version >> 28) & 0xf,
613 		       (dev->version >> 24) & 0xf,
614 		       (dev->version >> 16) & 0xff);
615 }
616 static DEVICE_ATTR_RO(hardware);
617 
nets_show(struct device * d,struct device_attribute * attr,char * buf)618 static ssize_t nets_show(struct device *d,
619 			 struct device_attribute *attr, char *buf)
620 {
621 	struct usb_interface *intf = to_usb_interface(d);
622 	struct esd_usb *dev = usb_get_intfdata(intf);
623 
624 	return sprintf(buf, "%d", dev->net_count);
625 }
626 static DEVICE_ATTR_RO(nets);
627 
esd_usb_send_msg(struct esd_usb * dev,union esd_usb_msg * msg)628 static int esd_usb_send_msg(struct esd_usb *dev, union esd_usb_msg *msg)
629 {
630 	int actual_length;
631 
632 	return usb_bulk_msg(dev->udev, dev->tx_pipe, msg,
633 			    msg->hdr.len * sizeof(u32), /* convert to # of bytes */
634 			    &actual_length,
635 			    1000);
636 }
637 
esd_usb_wait_msg(struct esd_usb * dev,union esd_usb_msg * msg)638 static int esd_usb_wait_msg(struct esd_usb *dev,
639 			    union esd_usb_msg *msg)
640 {
641 	int actual_length;
642 
643 	return usb_bulk_msg(dev->udev, dev->rx_pipe, msg,
644 			    sizeof(*msg), &actual_length, 1000);
645 }
646 
esd_usb_setup_rx_urbs(struct esd_usb * dev)647 static int esd_usb_setup_rx_urbs(struct esd_usb *dev)
648 {
649 	int i, err = 0;
650 
651 	if (dev->rxinitdone)
652 		return 0;
653 
654 	for (i = 0; i < ESD_USB_MAX_RX_URBS; i++) {
655 		struct urb *urb = NULL;
656 		u8 *buf = NULL;
657 		dma_addr_t buf_dma;
658 
659 		/* create a URB, and a buffer for it */
660 		urb = usb_alloc_urb(0, GFP_KERNEL);
661 		if (!urb) {
662 			err = -ENOMEM;
663 			break;
664 		}
665 
666 		buf = usb_alloc_coherent(dev->udev, ESD_USB_RX_BUFFER_SIZE, GFP_KERNEL,
667 					 &buf_dma);
668 		if (!buf) {
669 			dev_warn(dev->udev->dev.parent,
670 				 "No memory left for USB buffer\n");
671 			err = -ENOMEM;
672 			goto freeurb;
673 		}
674 
675 		urb->transfer_dma = buf_dma;
676 
677 		usb_fill_bulk_urb(urb, dev->udev, dev->rx_pipe,
678 				  buf, ESD_USB_RX_BUFFER_SIZE,
679 				  esd_usb_read_bulk_callback, dev);
680 		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
681 		usb_anchor_urb(urb, &dev->rx_submitted);
682 
683 		err = usb_submit_urb(urb, GFP_KERNEL);
684 		if (err) {
685 			usb_unanchor_urb(urb);
686 			usb_free_coherent(dev->udev, ESD_USB_RX_BUFFER_SIZE, buf,
687 					  urb->transfer_dma);
688 			goto freeurb;
689 		}
690 
691 		dev->rxbuf[i] = buf;
692 		dev->rxbuf_dma[i] = buf_dma;
693 
694 freeurb:
695 		/* Drop reference, USB core will take care of freeing it */
696 		usb_free_urb(urb);
697 		if (err)
698 			break;
699 	}
700 
701 	/* Did we submit any URBs */
702 	if (i == 0) {
703 		dev_err(dev->udev->dev.parent, "couldn't setup read URBs\n");
704 		return err;
705 	}
706 
707 	/* Warn if we've couldn't transmit all the URBs */
708 	if (i < ESD_USB_MAX_RX_URBS) {
709 		dev_warn(dev->udev->dev.parent,
710 			 "rx performance may be slow\n");
711 	}
712 
713 	dev->rxinitdone = 1;
714 	return 0;
715 }
716 
717 /* Start interface */
esd_usb_start(struct esd_usb_net_priv * priv)718 static int esd_usb_start(struct esd_usb_net_priv *priv)
719 {
720 	struct esd_usb *dev = priv->usb;
721 	struct net_device *netdev = priv->netdev;
722 	union esd_usb_msg *msg;
723 	int err, i;
724 
725 	msg = kmalloc_obj(*msg);
726 	if (!msg) {
727 		err = -ENOMEM;
728 		goto out;
729 	}
730 
731 	/* Enable all IDs
732 	 * The IDADD message takes up to 64 32 bit bitmasks (2048 bits).
733 	 * Each bit represents one 11 bit CAN identifier. A set bit
734 	 * enables reception of the corresponding CAN identifier. A cleared
735 	 * bit disabled this identifier. An additional bitmask value
736 	 * following the CAN 2.0A bits is used to enable reception of
737 	 * extended CAN frames. Only the LSB of this final mask is checked
738 	 * for the complete 29 bit ID range. The IDADD message also allows
739 	 * filter configuration for an ID subset. In this case you can add
740 	 * the number of the starting bitmask (0..64) to the filter.option
741 	 * field followed by only some bitmasks.
742 	 */
743 	msg->hdr.cmd = ESD_USB_CMD_IDADD;
744 	msg->hdr.len = sizeof(struct esd_usb_id_filter_msg) / sizeof(u32); /* # of 32bit words */
745 	msg->filter.net = priv->index;
746 	msg->filter.option = ESD_USB_ID_ENABLE; /* start with segment 0 */
747 	for (i = 0; i < ESD_USB_MAX_ID_SEGMENT; i++)
748 		msg->filter.mask[i] = cpu_to_le32(GENMASK(31, 0));
749 	/* enable 29bit extended IDs */
750 	msg->filter.mask[ESD_USB_MAX_ID_SEGMENT] = cpu_to_le32(BIT(0));
751 
752 	err = esd_usb_send_msg(dev, msg);
753 	if (err)
754 		goto out;
755 
756 	err = esd_usb_setup_rx_urbs(dev);
757 	if (err)
758 		goto out;
759 
760 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
761 
762 out:
763 	if (err == -ENODEV)
764 		netif_device_detach(netdev);
765 	if (err)
766 		netdev_err(netdev, "couldn't start device: %pe\n", ERR_PTR(err));
767 
768 	kfree(msg);
769 	return err;
770 }
771 
unlink_all_urbs(struct esd_usb * dev)772 static void unlink_all_urbs(struct esd_usb *dev)
773 {
774 	struct esd_usb_net_priv *priv;
775 	int i, j;
776 
777 	usb_kill_anchored_urbs(&dev->rx_submitted);
778 
779 	for (i = 0; i < ESD_USB_MAX_RX_URBS; ++i)
780 		usb_free_coherent(dev->udev, ESD_USB_RX_BUFFER_SIZE,
781 				  dev->rxbuf[i], dev->rxbuf_dma[i]);
782 
783 	for (i = 0; i < dev->net_count; i++) {
784 		priv = dev->nets[i];
785 		if (priv) {
786 			usb_kill_anchored_urbs(&priv->tx_submitted);
787 			atomic_set(&priv->active_tx_jobs, 0);
788 
789 			for (j = 0; j < ESD_USB_MAX_TX_URBS; j++)
790 				priv->tx_contexts[j].echo_index = ESD_USB_MAX_TX_URBS;
791 		}
792 	}
793 }
794 
esd_usb_open(struct net_device * netdev)795 static int esd_usb_open(struct net_device *netdev)
796 {
797 	struct esd_usb_net_priv *priv = netdev_priv(netdev);
798 	int err;
799 
800 	/* common open */
801 	err = open_candev(netdev);
802 	if (err)
803 		return err;
804 
805 	/* finally start device */
806 	err = esd_usb_start(priv);
807 	if (err) {
808 		close_candev(netdev);
809 		return err;
810 	}
811 
812 	netif_start_queue(netdev);
813 
814 	return 0;
815 }
816 
esd_usb_start_xmit(struct sk_buff * skb,struct net_device * netdev)817 static netdev_tx_t esd_usb_start_xmit(struct sk_buff *skb,
818 				      struct net_device *netdev)
819 {
820 	struct esd_usb_net_priv *priv = netdev_priv(netdev);
821 	struct esd_usb *dev = priv->usb;
822 	struct esd_tx_urb_context *context = NULL;
823 	struct net_device_stats *stats = &netdev->stats;
824 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
825 	union esd_usb_msg *msg;
826 	struct urb *urb;
827 	u8 *buf;
828 	int i, err;
829 	int ret = NETDEV_TX_OK;
830 	size_t size = sizeof(union esd_usb_msg);
831 
832 	if (can_dev_dropped_skb(netdev, skb))
833 		return NETDEV_TX_OK;
834 
835 	/* create a URB, and a buffer for it, and copy the data to the URB */
836 	urb = usb_alloc_urb(0, GFP_ATOMIC);
837 	if (!urb) {
838 		stats->tx_dropped++;
839 		dev_kfree_skb(skb);
840 		goto nourbmem;
841 	}
842 
843 	buf = usb_alloc_coherent(dev->udev, size, GFP_ATOMIC,
844 				 &urb->transfer_dma);
845 	if (!buf) {
846 		netdev_err(netdev, "No memory left for USB buffer\n");
847 		stats->tx_dropped++;
848 		dev_kfree_skb(skb);
849 		goto nobufmem;
850 	}
851 
852 	msg = (union esd_usb_msg *)buf;
853 
854 	/* minimal length as # of 32bit words */
855 	msg->hdr.len = offsetof(struct esd_usb_tx_msg, data) / sizeof(u32);
856 	msg->hdr.cmd = ESD_USB_CMD_CAN_TX;
857 	msg->tx.net = priv->index;
858 
859 	if (can_is_canfd_skb(skb)) {
860 		msg->tx.dlc = can_fd_len2dlc(cfd->len);
861 		msg->tx.dlc |= ESD_USB_FD;
862 
863 		if ((cfd->flags & CANFD_BRS) == 0)
864 			msg->tx.dlc |= ESD_USB_NO_BRS;
865 	} else {
866 		msg->tx.dlc = can_get_cc_dlc((struct can_frame *)cfd, priv->can.ctrlmode);
867 
868 		if (cfd->can_id & CAN_RTR_FLAG)
869 			msg->tx.dlc |= ESD_USB_RTR;
870 	}
871 
872 	msg->tx.id = cpu_to_le32(cfd->can_id & CAN_ERR_MASK);
873 
874 	if (cfd->can_id & CAN_EFF_FLAG)
875 		msg->tx.id |= cpu_to_le32(ESD_USB_EXTID);
876 
877 	memcpy(msg->tx.data_fd, cfd->data, cfd->len);
878 
879 	/* round up, then divide by 4 to add the payload length as # of 32bit words */
880 	msg->hdr.len += DIV_ROUND_UP(cfd->len, sizeof(u32));
881 
882 	for (i = 0; i < ESD_USB_MAX_TX_URBS; i++) {
883 		if (priv->tx_contexts[i].echo_index == ESD_USB_MAX_TX_URBS) {
884 			context = &priv->tx_contexts[i];
885 			break;
886 		}
887 	}
888 
889 	/* This may never happen */
890 	if (!context) {
891 		netdev_warn(netdev, "couldn't find free context\n");
892 		ret = NETDEV_TX_BUSY;
893 		goto releasebuf;
894 	}
895 
896 	context->priv = priv;
897 	context->echo_index = i;
898 
899 	/* hnd must not be 0 - MSB is stripped in txdone handling */
900 	msg->tx.hnd = BIT(31) | i; /* returned in TX done message */
901 
902 	usb_fill_bulk_urb(urb, dev->udev, dev->tx_pipe, buf,
903 			  msg->hdr.len * sizeof(u32), /* convert to # of bytes */
904 			  esd_usb_write_bulk_callback, context);
905 
906 	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
907 
908 	usb_anchor_urb(urb, &priv->tx_submitted);
909 
910 	can_put_echo_skb(skb, netdev, context->echo_index, 0);
911 
912 	atomic_inc(&priv->active_tx_jobs);
913 
914 	/* Slow down tx path */
915 	if (atomic_read(&priv->active_tx_jobs) >= ESD_USB_MAX_TX_URBS)
916 		netif_stop_queue(netdev);
917 
918 	err = usb_submit_urb(urb, GFP_ATOMIC);
919 	if (err) {
920 		can_free_echo_skb(netdev, context->echo_index, NULL);
921 
922 		atomic_dec(&priv->active_tx_jobs);
923 		usb_unanchor_urb(urb);
924 
925 		stats->tx_dropped++;
926 
927 		if (err == -ENODEV)
928 			netif_device_detach(netdev);
929 		else
930 			netdev_warn(netdev, "failed tx_urb %pe\n", ERR_PTR(err));
931 
932 		goto releasebuf;
933 	}
934 
935 	netif_trans_update(netdev);
936 
937 	/* Release our reference to this URB, the USB core will eventually free
938 	 * it entirely.
939 	 */
940 	usb_free_urb(urb);
941 
942 	return NETDEV_TX_OK;
943 
944 releasebuf:
945 	usb_free_coherent(dev->udev, size, buf, urb->transfer_dma);
946 
947 nobufmem:
948 	usb_free_urb(urb);
949 
950 nourbmem:
951 	return ret;
952 }
953 
954 /* Stop interface */
esd_usb_stop(struct esd_usb_net_priv * priv)955 static int esd_usb_stop(struct esd_usb_net_priv *priv)
956 {
957 	union esd_usb_msg *msg;
958 	int err;
959 	int i;
960 
961 	msg = kmalloc_obj(*msg);
962 	if (!msg)
963 		return -ENOMEM;
964 
965 	/* Disable all IDs (see esd_usb_start()) */
966 	msg->hdr.cmd = ESD_USB_CMD_IDADD;
967 	msg->hdr.len = sizeof(struct esd_usb_id_filter_msg) / sizeof(u32);/* # of 32bit words */
968 	msg->filter.net = priv->index;
969 	msg->filter.option = ESD_USB_ID_ENABLE; /* start with segment 0 */
970 	for (i = 0; i <= ESD_USB_MAX_ID_SEGMENT; i++)
971 		msg->filter.mask[i] = 0;
972 	err = esd_usb_send_msg(priv->usb, msg);
973 	if (err < 0) {
974 		netdev_err(priv->netdev, "sending idadd message failed: %pe\n", ERR_PTR(err));
975 		goto bail;
976 	}
977 
978 	/* set CAN controller to reset mode */
979 	msg->hdr.len = sizeof(struct esd_usb_set_baudrate_msg) / sizeof(u32); /* # of 32bit words */
980 	msg->hdr.cmd = ESD_USB_CMD_SETBAUD;
981 	msg->setbaud.net = priv->index;
982 	msg->setbaud.rsvd = 0;
983 	msg->setbaud.baud = cpu_to_le32(ESD_USB_NO_BAUDRATE);
984 	err = esd_usb_send_msg(priv->usb, msg);
985 	if (err < 0)
986 		netdev_err(priv->netdev, "sending setbaud message failed: %pe\n", ERR_PTR(err));
987 
988 bail:
989 	kfree(msg);
990 
991 	return err;
992 }
993 
esd_usb_close(struct net_device * netdev)994 static int esd_usb_close(struct net_device *netdev)
995 {
996 	struct esd_usb_net_priv *priv = netdev_priv(netdev);
997 	int err = 0;
998 
999 	if (!priv->usb->in_usb_disconnect) {
1000 		/* It's moot to try this in usb_disconnect()! */
1001 		err = esd_usb_stop(priv);
1002 	}
1003 
1004 	priv->can.state = CAN_STATE_STOPPED;
1005 
1006 	netif_stop_queue(netdev);
1007 
1008 	close_candev(netdev);
1009 
1010 	return err;
1011 }
1012 
1013 static const struct net_device_ops esd_usb_netdev_ops = {
1014 	.ndo_open = esd_usb_open,
1015 	.ndo_stop = esd_usb_close,
1016 	.ndo_start_xmit = esd_usb_start_xmit,
1017 };
1018 
1019 static const struct ethtool_ops esd_usb_ethtool_ops = {
1020 	.get_ts_info = ethtool_op_get_ts_info,
1021 };
1022 
1023 static const struct can_bittiming_const esd_usb_2_bittiming_const = {
1024 	.name = "esd_usb_2",
1025 	.tseg1_min = 1,
1026 	.tseg1_max = 16,
1027 	.tseg2_min = 1,
1028 	.tseg2_max = 8,
1029 	.sjw_max = 4,
1030 	.brp_min = 1,
1031 	.brp_max = 1024,
1032 	.brp_inc = 1,
1033 };
1034 
esd_usb_2_set_bittiming(struct net_device * netdev)1035 static int esd_usb_2_set_bittiming(struct net_device *netdev)
1036 {
1037 	const struct can_bittiming_const *btc = &esd_usb_2_bittiming_const;
1038 	struct esd_usb_net_priv *priv = netdev_priv(netdev);
1039 	struct can_bittiming *bt = &priv->can.bittiming;
1040 	union esd_usb_msg *msg;
1041 	int err;
1042 	u32 canbtr;
1043 	int sjw_shift;
1044 
1045 	canbtr = ESD_USB_UBR;
1046 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1047 		canbtr |= ESD_USB_LOM;
1048 
1049 	canbtr |= (bt->brp - 1) & (btc->brp_max - 1);
1050 
1051 	if (le16_to_cpu(priv->usb->udev->descriptor.idProduct) ==
1052 	    ESD_USB_CANUSBM_PRODUCT_ID)
1053 		sjw_shift = ESD_USB_M_SJW_SHIFT;
1054 	else
1055 		sjw_shift = ESD_USB_2_SJW_SHIFT;
1056 
1057 	canbtr |= ((bt->sjw - 1) & (btc->sjw_max - 1))
1058 		<< sjw_shift;
1059 	canbtr |= ((bt->prop_seg + bt->phase_seg1 - 1)
1060 		   & (btc->tseg1_max - 1))
1061 		<< ESD_USB_2_TSEG1_SHIFT;
1062 	canbtr |= ((bt->phase_seg2 - 1) & (btc->tseg2_max - 1))
1063 		<< ESD_USB_2_TSEG2_SHIFT;
1064 	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
1065 		canbtr |= ESD_USB_TRIPLE_SAMPLES;
1066 
1067 	msg = kmalloc_obj(*msg);
1068 	if (!msg)
1069 		return -ENOMEM;
1070 
1071 	msg->hdr.len = sizeof(struct esd_usb_set_baudrate_msg) / sizeof(u32); /* # of 32bit words */
1072 	msg->hdr.cmd = ESD_USB_CMD_SETBAUD;
1073 	msg->setbaud.net = priv->index;
1074 	msg->setbaud.rsvd = 0;
1075 	msg->setbaud.baud = cpu_to_le32(canbtr);
1076 
1077 	netdev_dbg(netdev, "setting BTR=%#x\n", canbtr);
1078 
1079 	err = esd_usb_send_msg(priv->usb, msg);
1080 
1081 	kfree(msg);
1082 	return err;
1083 }
1084 
1085 /* Nominal bittiming constants, see
1086  * Microchip SAM E70/S70/V70/V71, Data Sheet, Rev. G - 07/2022
1087  * 48.6.8 MCAN Nominal Bit Timing and Prescaler Register
1088  */
1089 static const struct can_bittiming_const esd_usb_3_nom_bittiming_const = {
1090 	.name = "esd_usb_3",
1091 	.tseg1_min = 2,
1092 	.tseg1_max = 256,
1093 	.tseg2_min = 2,
1094 	.tseg2_max = 128,
1095 	.sjw_max = 128,
1096 	.brp_min = 1,
1097 	.brp_max = 512,
1098 	.brp_inc = 1,
1099 };
1100 
1101 /* Data bittiming constants, see
1102  * Microchip SAM E70/S70/V70/V71, Data Sheet, Rev. G - 07/2022
1103  * 48.6.4 MCAN Data Bit Timing and Prescaler Register
1104  */
1105 static const struct can_bittiming_const esd_usb_3_data_bittiming_const = {
1106 	.name = "esd_usb_3",
1107 	.tseg1_min = 2,
1108 	.tseg1_max = 32,
1109 	.tseg2_min = 1,
1110 	.tseg2_max = 16,
1111 	.sjw_max = 8,
1112 	.brp_min = 1,
1113 	.brp_max = 32,
1114 	.brp_inc = 1,
1115 };
1116 
esd_usb_3_set_bittiming(struct net_device * netdev)1117 static int esd_usb_3_set_bittiming(struct net_device *netdev)
1118 {
1119 	const struct can_bittiming_const *nom_btc = &esd_usb_3_nom_bittiming_const;
1120 	const struct can_bittiming_const *data_btc = &esd_usb_3_data_bittiming_const;
1121 	struct esd_usb_net_priv *priv = netdev_priv(netdev);
1122 	struct can_bittiming *nom_bt = &priv->can.bittiming;
1123 	struct can_bittiming *data_bt = &priv->can.fd.data_bittiming;
1124 	struct esd_usb_3_set_baudrate_msg_x *baud_x;
1125 	union esd_usb_msg *msg;
1126 	u16 flags = 0;
1127 	int err;
1128 
1129 	msg = kmalloc_obj(*msg);
1130 	if (!msg)
1131 		return -ENOMEM;
1132 
1133 	baud_x = &msg->setbaud_x;
1134 
1135 	/* Canonical is the most reasonable mode for SocketCAN on CAN-USB/3 ... */
1136 	baud_x->mode = cpu_to_le16(ESD_USB_3_BAUDRATE_MODE_BTR_CANONICAL);
1137 
1138 	if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
1139 		flags |= ESD_USB_3_BAUDRATE_FLAG_LOM;
1140 
1141 	baud_x->nom.brp = cpu_to_le16(nom_bt->brp & (nom_btc->brp_max - 1));
1142 	baud_x->nom.sjw = cpu_to_le16(nom_bt->sjw & (nom_btc->sjw_max - 1));
1143 	baud_x->nom.tseg1 = cpu_to_le16((nom_bt->prop_seg + nom_bt->phase_seg1)
1144 					& (nom_btc->tseg1_max - 1));
1145 	baud_x->nom.tseg2 = cpu_to_le16(nom_bt->phase_seg2 & (nom_btc->tseg2_max - 1));
1146 
1147 	if (priv->can.ctrlmode & CAN_CTRLMODE_FD) {
1148 		baud_x->data.brp = cpu_to_le16(data_bt->brp & (data_btc->brp_max - 1));
1149 		baud_x->data.sjw = cpu_to_le16(data_bt->sjw & (data_btc->sjw_max - 1));
1150 		baud_x->data.tseg1 = cpu_to_le16((data_bt->prop_seg + data_bt->phase_seg1)
1151 						 & (data_btc->tseg1_max - 1));
1152 		baud_x->data.tseg2 = cpu_to_le16(data_bt->phase_seg2 & (data_btc->tseg2_max - 1));
1153 		flags |= ESD_USB_3_BAUDRATE_FLAG_FD;
1154 	}
1155 
1156 	/* Currently this driver only supports the automatic TDC mode */
1157 	baud_x->tdc.tdc_mode = ESD_USB_3_TDC_MODE_AUTO;
1158 	baud_x->tdc.ssp_offset = 0;
1159 	baud_x->tdc.ssp_shift = 0;
1160 	baud_x->tdc.tdc_filter = 0;
1161 
1162 	baud_x->flags = cpu_to_le16(flags);
1163 	baud_x->net = priv->index;
1164 	baud_x->rsvd = 0;
1165 
1166 	/* set len as # of 32bit words */
1167 	msg->hdr.len = sizeof(struct esd_usb_3_set_baudrate_msg_x) / sizeof(u32);
1168 	msg->hdr.cmd = ESD_USB_CMD_SETBAUD;
1169 
1170 	netdev_dbg(netdev,
1171 		   "ctrlmode=%#x/%#x, esd-net=%u, esd-mode=%#x, esd-flags=%#x\n",
1172 		   priv->can.ctrlmode, priv->can.ctrlmode_supported,
1173 		   priv->index, le16_to_cpu(baud_x->mode), flags);
1174 
1175 	err = esd_usb_send_msg(priv->usb, msg);
1176 
1177 	kfree(msg);
1178 	return err;
1179 }
1180 
esd_usb_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)1181 static int esd_usb_get_berr_counter(const struct net_device *netdev,
1182 				    struct can_berr_counter *bec)
1183 {
1184 	struct esd_usb_net_priv *priv = netdev_priv(netdev);
1185 
1186 	bec->txerr = priv->bec.txerr;
1187 	bec->rxerr = priv->bec.rxerr;
1188 
1189 	return 0;
1190 }
1191 
esd_usb_set_mode(struct net_device * netdev,enum can_mode mode)1192 static int esd_usb_set_mode(struct net_device *netdev, enum can_mode mode)
1193 {
1194 	switch (mode) {
1195 	case CAN_MODE_START:
1196 		netif_wake_queue(netdev);
1197 		break;
1198 
1199 	default:
1200 		return -EOPNOTSUPP;
1201 	}
1202 
1203 	return 0;
1204 }
1205 
esd_usb_probe_one_net(struct usb_interface * intf,int index)1206 static int esd_usb_probe_one_net(struct usb_interface *intf, int index)
1207 {
1208 	struct esd_usb *dev = usb_get_intfdata(intf);
1209 	struct net_device *netdev;
1210 	struct esd_usb_net_priv *priv;
1211 	int err = 0;
1212 	int i;
1213 
1214 	netdev = alloc_candev(sizeof(*priv), ESD_USB_MAX_TX_URBS);
1215 	if (!netdev) {
1216 		dev_err(&intf->dev, "couldn't alloc candev\n");
1217 		err = -ENOMEM;
1218 		goto done;
1219 	}
1220 
1221 	priv = netdev_priv(netdev);
1222 
1223 	init_usb_anchor(&priv->tx_submitted);
1224 	atomic_set(&priv->active_tx_jobs, 0);
1225 
1226 	for (i = 0; i < ESD_USB_MAX_TX_URBS; i++)
1227 		priv->tx_contexts[i].echo_index = ESD_USB_MAX_TX_URBS;
1228 
1229 	priv->usb = dev;
1230 	priv->netdev = netdev;
1231 	priv->index = index;
1232 
1233 	priv->can.state = CAN_STATE_STOPPED;
1234 	priv->can.ctrlmode_supported = CAN_CTRLMODE_LISTENONLY |
1235 		CAN_CTRLMODE_CC_LEN8_DLC |
1236 		CAN_CTRLMODE_BERR_REPORTING;
1237 
1238 	switch (le16_to_cpu(dev->udev->descriptor.idProduct)) {
1239 	case ESD_USB_CANUSB3_PRODUCT_ID:
1240 		priv->can.clock.freq = ESD_USB_3_CAN_CLOCK;
1241 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
1242 		priv->can.bittiming_const = &esd_usb_3_nom_bittiming_const;
1243 		priv->can.fd.data_bittiming_const = &esd_usb_3_data_bittiming_const;
1244 		priv->can.do_set_bittiming = esd_usb_3_set_bittiming;
1245 		priv->can.fd.do_set_data_bittiming = esd_usb_3_set_bittiming;
1246 		break;
1247 
1248 	case ESD_USB_CANUSBM_PRODUCT_ID:
1249 		priv->can.clock.freq = ESD_USB_M_CAN_CLOCK;
1250 		priv->can.bittiming_const = &esd_usb_2_bittiming_const;
1251 		priv->can.do_set_bittiming = esd_usb_2_set_bittiming;
1252 		break;
1253 
1254 	case ESD_USB_CANUSB2_PRODUCT_ID:
1255 	default:
1256 		priv->can.clock.freq = ESD_USB_2_CAN_CLOCK;
1257 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1258 		priv->can.bittiming_const = &esd_usb_2_bittiming_const;
1259 		priv->can.do_set_bittiming = esd_usb_2_set_bittiming;
1260 		break;
1261 	}
1262 
1263 	priv->can.do_set_mode = esd_usb_set_mode;
1264 	priv->can.do_get_berr_counter = esd_usb_get_berr_counter;
1265 
1266 	netdev->flags |= IFF_ECHO; /* we support local echo */
1267 
1268 	netdev->netdev_ops = &esd_usb_netdev_ops;
1269 	netdev->ethtool_ops = &esd_usb_ethtool_ops;
1270 
1271 	SET_NETDEV_DEV(netdev, &intf->dev);
1272 	netdev->dev_id = index;
1273 
1274 	err = register_candev(netdev);
1275 	if (err) {
1276 		dev_err(&intf->dev, "couldn't register CAN device: %pe\n", ERR_PTR(err));
1277 		free_candev(netdev);
1278 		err = -ENOMEM;
1279 		goto done;
1280 	}
1281 
1282 	dev->nets[index] = priv;
1283 	netdev_info(netdev, "registered\n");
1284 
1285 done:
1286 	return err;
1287 }
1288 
1289 /* probe function for new USB devices
1290  *
1291  * check version information and number of available
1292  * CAN interfaces
1293  */
esd_usb_probe(struct usb_interface * intf,const struct usb_device_id * id)1294 static int esd_usb_probe(struct usb_interface *intf,
1295 			 const struct usb_device_id *id)
1296 {
1297 	struct usb_endpoint_descriptor *ep_in, *ep_out;
1298 	struct esd_usb *dev;
1299 	union esd_usb_msg *msg;
1300 	int i, err;
1301 
1302 	err = usb_find_common_endpoints(intf->cur_altsetting, &ep_in, &ep_out,
1303 					NULL, NULL);
1304 	if (err)
1305 		return err;
1306 
1307 	dev = kzalloc_obj(*dev);
1308 	if (!dev) {
1309 		err = -ENOMEM;
1310 		goto done;
1311 	}
1312 
1313 	dev->udev = interface_to_usbdev(intf);
1314 	dev->rx_pipe = usb_rcvbulkpipe(dev->udev, ep_in->bEndpointAddress);
1315 	dev->tx_pipe = usb_sndbulkpipe(dev->udev, ep_out->bEndpointAddress);
1316 
1317 	init_usb_anchor(&dev->rx_submitted);
1318 
1319 	usb_set_intfdata(intf, dev);
1320 
1321 	msg = kmalloc_obj(*msg);
1322 	if (!msg) {
1323 		err = -ENOMEM;
1324 		goto free_msg;
1325 	}
1326 
1327 	/* query number of CAN interfaces (nets) */
1328 	msg->hdr.cmd = ESD_USB_CMD_VERSION;
1329 	msg->hdr.len = sizeof(struct esd_usb_version_msg) / sizeof(u32); /* # of 32bit words */
1330 	msg->version.rsvd = 0;
1331 	msg->version.flags = 0;
1332 	msg->version.drv_version = 0;
1333 
1334 	err = esd_usb_send_msg(dev, msg);
1335 	if (err < 0) {
1336 		dev_err(&intf->dev, "sending version message failed\n");
1337 		goto free_msg;
1338 	}
1339 
1340 	err = esd_usb_wait_msg(dev, msg);
1341 	if (err < 0) {
1342 		dev_err(&intf->dev, "no version message answer\n");
1343 		goto free_msg;
1344 	}
1345 
1346 	dev->net_count = (int)msg->version_reply.nets;
1347 	dev->version = le32_to_cpu(msg->version_reply.version);
1348 
1349 	if (device_create_file(&intf->dev, &dev_attr_firmware))
1350 		dev_err(&intf->dev,
1351 			"Couldn't create device file for firmware\n");
1352 
1353 	if (device_create_file(&intf->dev, &dev_attr_hardware))
1354 		dev_err(&intf->dev,
1355 			"Couldn't create device file for hardware\n");
1356 
1357 	if (device_create_file(&intf->dev, &dev_attr_nets))
1358 		dev_err(&intf->dev,
1359 			"Couldn't create device file for nets\n");
1360 
1361 	/* do per device probing */
1362 	for (i = 0; i < dev->net_count; i++)
1363 		esd_usb_probe_one_net(intf, i);
1364 
1365 free_msg:
1366 	kfree(msg);
1367 	if (err)
1368 		kfree(dev);
1369 done:
1370 	return err;
1371 }
1372 
1373 /* called by the usb core when the device is removed from the system */
esd_usb_disconnect(struct usb_interface * intf)1374 static void esd_usb_disconnect(struct usb_interface *intf)
1375 {
1376 	struct esd_usb *dev = usb_get_intfdata(intf);
1377 	struct net_device *netdev;
1378 	int i;
1379 
1380 	device_remove_file(&intf->dev, &dev_attr_firmware);
1381 	device_remove_file(&intf->dev, &dev_attr_hardware);
1382 	device_remove_file(&intf->dev, &dev_attr_nets);
1383 
1384 	usb_set_intfdata(intf, NULL);
1385 
1386 	if (dev) {
1387 		dev->in_usb_disconnect = 1;
1388 		for (i = 0; i < dev->net_count; i++) {
1389 			if (dev->nets[i]) {
1390 				netdev = dev->nets[i]->netdev;
1391 				netdev_info(netdev, "unregister\n");
1392 				unregister_netdev(netdev);
1393 				free_candev(netdev);
1394 			}
1395 		}
1396 		unlink_all_urbs(dev);
1397 		kfree(dev);
1398 	}
1399 }
1400 
1401 /* usb specific object needed to register this driver with the usb subsystem */
1402 static struct usb_driver esd_usb_driver = {
1403 	.name = KBUILD_MODNAME,
1404 	.probe = esd_usb_probe,
1405 	.disconnect = esd_usb_disconnect,
1406 	.id_table = esd_usb_table,
1407 };
1408 
1409 module_usb_driver(esd_usb_driver);
1410