1 // SPDX-License-Identifier: GPL-2.0-only
2 /* CAN driver for Geschwister Schneider USB/CAN devices
3 * and bytewerk.org candleLight USB CAN interfaces.
4 *
5 * Copyright (C) 2013-2016 Geschwister Schneider Technologie-,
6 * Entwicklungs- und Vertriebs UG (Haftungsbeschränkt).
7 * Copyright (C) 2016 Hubert Denkmair
8 * Copyright (c) 2023 Pengutronix, Marc Kleine-Budde <kernel@pengutronix.de>
9 *
10 * Many thanks to all socketcan devs!
11 */
12
13 #include <linux/bitfield.h>
14 #include <linux/clocksource.h>
15 #include <linux/ethtool.h>
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/netdevice.h>
19 #include <linux/signal.h>
20 #include <linux/timecounter.h>
21 #include <linux/units.h>
22 #include <linux/usb.h>
23 #include <linux/workqueue.h>
24
25 #include <linux/can.h>
26 #include <linux/can/dev.h>
27 #include <linux/can/error.h>
28 #include <linux/can/rx-offload.h>
29
30 /* Device specific constants */
31 #define USB_GS_USB_1_VENDOR_ID 0x1d50
32 #define USB_GS_USB_1_PRODUCT_ID 0x606f
33
34 #define USB_CANDLELIGHT_VENDOR_ID 0x1209
35 #define USB_CANDLELIGHT_PRODUCT_ID 0x2323
36
37 #define USB_CES_CANEXT_FD_VENDOR_ID 0x1cd2
38 #define USB_CES_CANEXT_FD_PRODUCT_ID 0x606f
39
40 #define USB_ABE_CANDEBUGGER_FD_VENDOR_ID 0x16d0
41 #define USB_ABE_CANDEBUGGER_FD_PRODUCT_ID 0x10b8
42
43 #define USB_XYLANTA_SAINT3_VENDOR_ID 0x16d0
44 #define USB_XYLANTA_SAINT3_PRODUCT_ID 0x0f30
45
46 #define USB_CANNECTIVITY_VENDOR_ID 0x1209
47 #define USB_CANNECTIVITY_PRODUCT_ID 0xca01
48
49 /* Timestamp 32 bit timer runs at 1 MHz (1 µs tick). Worker accounts
50 * for timer overflow (will be after ~71 minutes)
51 */
52 #define GS_USB_TIMESTAMP_TIMER_HZ (1 * HZ_PER_MHZ)
53 #define GS_USB_TIMESTAMP_WORK_DELAY_SEC 1800
54 static_assert(GS_USB_TIMESTAMP_WORK_DELAY_SEC <
55 CYCLECOUNTER_MASK(32) / GS_USB_TIMESTAMP_TIMER_HZ / 2);
56
57 /* Device specific constants */
58 enum gs_usb_breq {
59 GS_USB_BREQ_HOST_FORMAT = 0,
60 GS_USB_BREQ_BITTIMING,
61 GS_USB_BREQ_MODE,
62 GS_USB_BREQ_BERR,
63 GS_USB_BREQ_BT_CONST,
64 GS_USB_BREQ_DEVICE_CONFIG,
65 GS_USB_BREQ_TIMESTAMP,
66 GS_USB_BREQ_IDENTIFY,
67 GS_USB_BREQ_GET_USER_ID,
68 GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING = GS_USB_BREQ_GET_USER_ID,
69 GS_USB_BREQ_SET_USER_ID,
70 GS_USB_BREQ_DATA_BITTIMING,
71 GS_USB_BREQ_BT_CONST_EXT,
72 GS_USB_BREQ_SET_TERMINATION,
73 GS_USB_BREQ_GET_TERMINATION,
74 GS_USB_BREQ_GET_STATE,
75 };
76
77 enum gs_can_mode {
78 /* reset a channel. turns it off */
79 GS_CAN_MODE_RESET = 0,
80 /* starts a channel */
81 GS_CAN_MODE_START
82 };
83
84 enum gs_can_state {
85 GS_CAN_STATE_ERROR_ACTIVE = 0,
86 GS_CAN_STATE_ERROR_WARNING,
87 GS_CAN_STATE_ERROR_PASSIVE,
88 GS_CAN_STATE_BUS_OFF,
89 GS_CAN_STATE_STOPPED,
90 GS_CAN_STATE_SLEEPING
91 };
92
93 enum gs_can_identify_mode {
94 GS_CAN_IDENTIFY_OFF = 0,
95 GS_CAN_IDENTIFY_ON
96 };
97
98 enum gs_can_termination_state {
99 GS_CAN_TERMINATION_STATE_OFF = 0,
100 GS_CAN_TERMINATION_STATE_ON
101 };
102
103 #define GS_USB_TERMINATION_DISABLED CAN_TERMINATION_DISABLED
104 #define GS_USB_TERMINATION_ENABLED 120
105
106 /* data types passed between host and device */
107
108 /* The firmware on the original USB2CAN by Geschwister Schneider
109 * Technologie Entwicklungs- und Vertriebs UG exchanges all data
110 * between the host and the device in host byte order. This is done
111 * with the struct gs_host_config::byte_order member, which is sent
112 * first to indicate the desired byte order.
113 *
114 * The widely used open source firmware candleLight doesn't support
115 * this feature and exchanges the data in little endian byte order.
116 */
117 struct gs_host_config {
118 __le32 byte_order;
119 } __packed;
120
121 struct gs_device_config {
122 u8 reserved1;
123 u8 reserved2;
124 u8 reserved3;
125 u8 icount;
126 __le32 sw_version;
127 __le32 hw_version;
128 } __packed;
129
130 #define GS_CAN_MODE_NORMAL 0
131 #define GS_CAN_MODE_LISTEN_ONLY BIT(0)
132 #define GS_CAN_MODE_LOOP_BACK BIT(1)
133 #define GS_CAN_MODE_TRIPLE_SAMPLE BIT(2)
134 #define GS_CAN_MODE_ONE_SHOT BIT(3)
135 #define GS_CAN_MODE_HW_TIMESTAMP BIT(4)
136 /* GS_CAN_FEATURE_IDENTIFY BIT(5) */
137 /* GS_CAN_FEATURE_USER_ID BIT(6) */
138 #define GS_CAN_MODE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
139 #define GS_CAN_MODE_FD BIT(8)
140 /* GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9) */
141 /* GS_CAN_FEATURE_BT_CONST_EXT BIT(10) */
142 /* GS_CAN_FEATURE_TERMINATION BIT(11) */
143 #define GS_CAN_MODE_BERR_REPORTING BIT(12)
144 /* GS_CAN_FEATURE_GET_STATE BIT(13) */
145
146 struct gs_device_mode {
147 __le32 mode;
148 __le32 flags;
149 } __packed;
150
151 struct gs_device_state {
152 __le32 state;
153 __le32 rxerr;
154 __le32 txerr;
155 } __packed;
156
157 struct gs_device_bittiming {
158 __le32 prop_seg;
159 __le32 phase_seg1;
160 __le32 phase_seg2;
161 __le32 sjw;
162 __le32 brp;
163 } __packed;
164
165 struct gs_identify_mode {
166 __le32 mode;
167 } __packed;
168
169 struct gs_device_termination_state {
170 __le32 state;
171 } __packed;
172
173 #define GS_CAN_FEATURE_LISTEN_ONLY BIT(0)
174 #define GS_CAN_FEATURE_LOOP_BACK BIT(1)
175 #define GS_CAN_FEATURE_TRIPLE_SAMPLE BIT(2)
176 #define GS_CAN_FEATURE_ONE_SHOT BIT(3)
177 #define GS_CAN_FEATURE_HW_TIMESTAMP BIT(4)
178 #define GS_CAN_FEATURE_IDENTIFY BIT(5)
179 #define GS_CAN_FEATURE_USER_ID BIT(6)
180 #define GS_CAN_FEATURE_PAD_PKTS_TO_MAX_PKT_SIZE BIT(7)
181 #define GS_CAN_FEATURE_FD BIT(8)
182 #define GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX BIT(9)
183 #define GS_CAN_FEATURE_BT_CONST_EXT BIT(10)
184 #define GS_CAN_FEATURE_TERMINATION BIT(11)
185 #define GS_CAN_FEATURE_BERR_REPORTING BIT(12)
186 #define GS_CAN_FEATURE_GET_STATE BIT(13)
187 #define GS_CAN_FEATURE_MASK GENMASK(13, 0)
188
189 /* internal quirks - keep in GS_CAN_FEATURE space for now */
190
191 /* CANtact Pro original firmware:
192 * BREQ DATA_BITTIMING overlaps with GET_USER_ID
193 */
194 #define GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO BIT(31)
195
196 struct gs_device_bt_const {
197 __le32 feature;
198 __le32 fclk_can;
199 __le32 tseg1_min;
200 __le32 tseg1_max;
201 __le32 tseg2_min;
202 __le32 tseg2_max;
203 __le32 sjw_max;
204 __le32 brp_min;
205 __le32 brp_max;
206 __le32 brp_inc;
207 } __packed;
208
209 struct gs_device_bt_const_extended {
210 __le32 feature;
211 __le32 fclk_can;
212 __le32 tseg1_min;
213 __le32 tseg1_max;
214 __le32 tseg2_min;
215 __le32 tseg2_max;
216 __le32 sjw_max;
217 __le32 brp_min;
218 __le32 brp_max;
219 __le32 brp_inc;
220
221 __le32 dtseg1_min;
222 __le32 dtseg1_max;
223 __le32 dtseg2_min;
224 __le32 dtseg2_max;
225 __le32 dsjw_max;
226 __le32 dbrp_min;
227 __le32 dbrp_max;
228 __le32 dbrp_inc;
229 } __packed;
230
231 #define GS_CAN_FLAG_OVERFLOW BIT(0)
232 #define GS_CAN_FLAG_FD BIT(1)
233 #define GS_CAN_FLAG_BRS BIT(2)
234 #define GS_CAN_FLAG_ESI BIT(3)
235
236 struct classic_can {
237 u8 data[8];
238 } __packed;
239
240 struct classic_can_ts {
241 u8 data[8];
242 __le32 timestamp_us;
243 } __packed;
244
245 struct classic_can_quirk {
246 u8 data[8];
247 u8 quirk;
248 } __packed;
249
250 struct canfd {
251 u8 data[64];
252 } __packed;
253
254 struct canfd_ts {
255 u8 data[64];
256 __le32 timestamp_us;
257 } __packed;
258
259 struct canfd_quirk {
260 u8 data[64];
261 u8 quirk;
262 } __packed;
263
264 /* struct gs_host_frame::echo_id == GS_HOST_FRAME_ECHO_ID_RX indicates
265 * a regular RX'ed CAN frame
266 */
267 #define GS_HOST_FRAME_ECHO_ID_RX 0xffffffff
268
269 struct gs_host_frame {
270 struct_group(header,
271 u32 echo_id;
272 __le32 can_id;
273
274 u8 can_dlc;
275 u8 channel;
276 u8 flags;
277 u8 reserved;
278 );
279
280 union {
281 DECLARE_FLEX_ARRAY(struct classic_can, classic_can);
282 DECLARE_FLEX_ARRAY(struct classic_can_ts, classic_can_ts);
283 DECLARE_FLEX_ARRAY(struct classic_can_quirk, classic_can_quirk);
284 DECLARE_FLEX_ARRAY(struct canfd, canfd);
285 DECLARE_FLEX_ARRAY(struct canfd_ts, canfd_ts);
286 DECLARE_FLEX_ARRAY(struct canfd_quirk, canfd_quirk);
287 };
288 } __packed;
289 /* The GS USB devices make use of the same flags and masks as in
290 * linux/can.h and linux/can/error.h, and no additional mapping is necessary.
291 */
292
293 /* Only send a max of GS_MAX_TX_URBS frames per channel at a time. */
294 #define GS_MAX_TX_URBS 10
295 /* Only launch a max of GS_MAX_RX_URBS usb requests at a time. */
296 #define GS_MAX_RX_URBS 30
297 #define GS_NAPI_WEIGHT 32
298
299 struct gs_tx_context {
300 struct gs_can *dev;
301 unsigned int echo_id;
302 };
303
304 struct gs_can {
305 struct can_priv can; /* must be the first member */
306
307 struct can_rx_offload offload;
308 struct gs_usb *parent;
309
310 struct net_device *netdev;
311 struct usb_device *udev;
312
313 struct can_bittiming_const bt_const, data_bt_const;
314 unsigned int channel; /* channel number */
315
316 u32 feature;
317 unsigned int hf_size_tx;
318
319 /* This lock prevents a race condition between xmit and receive. */
320 spinlock_t tx_ctx_lock;
321 struct gs_tx_context tx_context[GS_MAX_TX_URBS];
322
323 struct usb_anchor tx_submitted;
324 atomic_t active_tx_urbs;
325 };
326
327 /* usb interface struct */
328 struct gs_usb {
329 struct usb_anchor rx_submitted;
330 struct usb_device *udev;
331
332 /* time counter for hardware timestamps */
333 struct cyclecounter cc;
334 struct timecounter tc;
335 spinlock_t tc_lock; /* spinlock to guard access tc->cycle_last */
336 struct delayed_work timestamp;
337
338 unsigned int hf_size_rx;
339 u8 active_channels;
340 u8 channel_cnt;
341
342 unsigned int pipe_in;
343 unsigned int pipe_out;
344 struct gs_can *canch[] __counted_by(channel_cnt);
345 };
346
347 /* 'allocate' a tx context.
348 * returns a valid tx context or NULL if there is no space.
349 */
gs_alloc_tx_context(struct gs_can * dev)350 static struct gs_tx_context *gs_alloc_tx_context(struct gs_can *dev)
351 {
352 int i = 0;
353 unsigned long flags;
354
355 spin_lock_irqsave(&dev->tx_ctx_lock, flags);
356
357 for (; i < GS_MAX_TX_URBS; i++) {
358 if (dev->tx_context[i].echo_id == GS_MAX_TX_URBS) {
359 dev->tx_context[i].echo_id = i;
360 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
361 return &dev->tx_context[i];
362 }
363 }
364
365 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
366 return NULL;
367 }
368
369 /* releases a tx context
370 */
gs_free_tx_context(struct gs_tx_context * txc)371 static void gs_free_tx_context(struct gs_tx_context *txc)
372 {
373 txc->echo_id = GS_MAX_TX_URBS;
374 }
375
376 /* Get a tx context by id.
377 */
gs_get_tx_context(struct gs_can * dev,unsigned int id)378 static struct gs_tx_context *gs_get_tx_context(struct gs_can *dev,
379 unsigned int id)
380 {
381 unsigned long flags;
382
383 if (id < GS_MAX_TX_URBS) {
384 spin_lock_irqsave(&dev->tx_ctx_lock, flags);
385 if (dev->tx_context[id].echo_id == id) {
386 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
387 return &dev->tx_context[id];
388 }
389 spin_unlock_irqrestore(&dev->tx_ctx_lock, flags);
390 }
391 return NULL;
392 }
393
gs_cmd_reset(struct gs_can * dev)394 static int gs_cmd_reset(struct gs_can *dev)
395 {
396 struct gs_device_mode dm = {
397 .mode = cpu_to_le32(GS_CAN_MODE_RESET),
398 };
399
400 return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_MODE,
401 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
402 dev->channel, 0, &dm, sizeof(dm), 1000,
403 GFP_KERNEL);
404 }
405
gs_usb_get_timestamp(const struct gs_usb * parent,u32 * timestamp_p)406 static inline int gs_usb_get_timestamp(const struct gs_usb *parent,
407 u32 *timestamp_p)
408 {
409 __le32 timestamp;
410 int rc;
411
412 rc = usb_control_msg_recv(parent->udev, 0, GS_USB_BREQ_TIMESTAMP,
413 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
414 0, 0,
415 ×tamp, sizeof(timestamp),
416 USB_CTRL_GET_TIMEOUT,
417 GFP_KERNEL);
418 if (rc)
419 return rc;
420
421 *timestamp_p = le32_to_cpu(timestamp);
422
423 return 0;
424 }
425
gs_usb_timestamp_read(struct cyclecounter * cc)426 static u64 gs_usb_timestamp_read(struct cyclecounter *cc) __must_hold(&dev->tc_lock)
427 {
428 struct gs_usb *parent = container_of(cc, struct gs_usb, cc);
429 u32 timestamp = 0;
430 int err;
431
432 lockdep_assert_held(&parent->tc_lock);
433
434 /* drop lock for synchronous USB transfer */
435 spin_unlock_bh(&parent->tc_lock);
436 err = gs_usb_get_timestamp(parent, ×tamp);
437 spin_lock_bh(&parent->tc_lock);
438 if (err)
439 dev_err(&parent->udev->dev,
440 "Error %d while reading timestamp. HW timestamps may be inaccurate.",
441 err);
442
443 return timestamp;
444 }
445
gs_usb_timestamp_work(struct work_struct * work)446 static void gs_usb_timestamp_work(struct work_struct *work)
447 {
448 struct delayed_work *delayed_work = to_delayed_work(work);
449 struct gs_usb *parent;
450
451 parent = container_of(delayed_work, struct gs_usb, timestamp);
452 spin_lock_bh(&parent->tc_lock);
453 timecounter_read(&parent->tc);
454 spin_unlock_bh(&parent->tc_lock);
455
456 schedule_delayed_work(&parent->timestamp,
457 GS_USB_TIMESTAMP_WORK_DELAY_SEC * HZ);
458 }
459
gs_usb_skb_set_timestamp(struct gs_can * dev,struct sk_buff * skb,u32 timestamp)460 static void gs_usb_skb_set_timestamp(struct gs_can *dev,
461 struct sk_buff *skb, u32 timestamp)
462 {
463 struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
464 struct gs_usb *parent = dev->parent;
465 u64 ns;
466
467 spin_lock_bh(&parent->tc_lock);
468 ns = timecounter_cyc2time(&parent->tc, timestamp);
469 spin_unlock_bh(&parent->tc_lock);
470
471 hwtstamps->hwtstamp = ns_to_ktime(ns);
472 }
473
gs_usb_timestamp_init(struct gs_usb * parent)474 static void gs_usb_timestamp_init(struct gs_usb *parent)
475 {
476 struct cyclecounter *cc = &parent->cc;
477
478 cc->read = gs_usb_timestamp_read;
479 cc->mask = CYCLECOUNTER_MASK(32);
480 cc->shift = 32 - bits_per(NSEC_PER_SEC / GS_USB_TIMESTAMP_TIMER_HZ);
481 cc->mult = clocksource_hz2mult(GS_USB_TIMESTAMP_TIMER_HZ, cc->shift);
482
483 spin_lock_init(&parent->tc_lock);
484 spin_lock_bh(&parent->tc_lock);
485 timecounter_init(&parent->tc, &parent->cc, ktime_get_real_ns());
486 spin_unlock_bh(&parent->tc_lock);
487
488 INIT_DELAYED_WORK(&parent->timestamp, gs_usb_timestamp_work);
489 schedule_delayed_work(&parent->timestamp,
490 GS_USB_TIMESTAMP_WORK_DELAY_SEC * HZ);
491 }
492
gs_usb_timestamp_stop(struct gs_usb * parent)493 static void gs_usb_timestamp_stop(struct gs_usb *parent)
494 {
495 cancel_delayed_work_sync(&parent->timestamp);
496 }
497
gs_update_state(struct gs_can * dev,struct can_frame * cf)498 static void gs_update_state(struct gs_can *dev, struct can_frame *cf)
499 {
500 struct can_device_stats *can_stats = &dev->can.can_stats;
501
502 if (cf->can_id & CAN_ERR_RESTARTED) {
503 dev->can.state = CAN_STATE_ERROR_ACTIVE;
504 can_stats->restarts++;
505 } else if (cf->can_id & CAN_ERR_BUSOFF) {
506 dev->can.state = CAN_STATE_BUS_OFF;
507 can_stats->bus_off++;
508 } else if (cf->can_id & CAN_ERR_CRTL) {
509 if ((cf->data[1] & CAN_ERR_CRTL_TX_WARNING) ||
510 (cf->data[1] & CAN_ERR_CRTL_RX_WARNING)) {
511 dev->can.state = CAN_STATE_ERROR_WARNING;
512 can_stats->error_warning++;
513 } else if ((cf->data[1] & CAN_ERR_CRTL_TX_PASSIVE) ||
514 (cf->data[1] & CAN_ERR_CRTL_RX_PASSIVE)) {
515 dev->can.state = CAN_STATE_ERROR_PASSIVE;
516 can_stats->error_passive++;
517 } else {
518 dev->can.state = CAN_STATE_ERROR_ACTIVE;
519 }
520 }
521 }
522
gs_usb_set_timestamp(struct gs_can * dev,struct sk_buff * skb,const struct gs_host_frame * hf)523 static u32 gs_usb_set_timestamp(struct gs_can *dev, struct sk_buff *skb,
524 const struct gs_host_frame *hf)
525 {
526 u32 timestamp;
527
528 if (hf->flags & GS_CAN_FLAG_FD)
529 timestamp = le32_to_cpu(hf->canfd_ts->timestamp_us);
530 else
531 timestamp = le32_to_cpu(hf->classic_can_ts->timestamp_us);
532
533 if (skb)
534 gs_usb_skb_set_timestamp(dev, skb, timestamp);
535
536 return timestamp;
537 }
538
gs_usb_rx_offload(struct gs_can * dev,struct sk_buff * skb,const struct gs_host_frame * hf)539 static void gs_usb_rx_offload(struct gs_can *dev, struct sk_buff *skb,
540 const struct gs_host_frame *hf)
541 {
542 struct can_rx_offload *offload = &dev->offload;
543 int rc;
544
545 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP) {
546 const u32 ts = gs_usb_set_timestamp(dev, skb, hf);
547
548 rc = can_rx_offload_queue_timestamp(offload, skb, ts);
549 } else {
550 rc = can_rx_offload_queue_tail(offload, skb);
551 }
552
553 if (rc)
554 dev->netdev->stats.rx_fifo_errors++;
555 }
556
557 static unsigned int
gs_usb_get_echo_skb(struct gs_can * dev,struct sk_buff * skb,const struct gs_host_frame * hf)558 gs_usb_get_echo_skb(struct gs_can *dev, struct sk_buff *skb,
559 const struct gs_host_frame *hf)
560 {
561 struct can_rx_offload *offload = &dev->offload;
562 const u32 echo_id = hf->echo_id;
563 unsigned int len;
564
565 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP) {
566 const u32 ts = gs_usb_set_timestamp(dev, skb, hf);
567
568 len = can_rx_offload_get_echo_skb_queue_timestamp(offload, echo_id,
569 ts, NULL);
570 } else {
571 len = can_rx_offload_get_echo_skb_queue_tail(offload, echo_id,
572 NULL);
573 }
574
575 return len;
576 }
577
578 static unsigned int
gs_usb_get_minimum_rx_length(const struct gs_can * dev,const struct gs_host_frame * hf,unsigned int * data_length_p)579 gs_usb_get_minimum_rx_length(const struct gs_can *dev, const struct gs_host_frame *hf,
580 unsigned int *data_length_p)
581 {
582 unsigned int minimum_length, data_length = 0;
583
584 if (hf->flags & GS_CAN_FLAG_FD) {
585 if (hf->echo_id == GS_HOST_FRAME_ECHO_ID_RX)
586 data_length = can_fd_dlc2len(hf->can_dlc);
587
588 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
589 /* timestamp follows data field of max size */
590 minimum_length = struct_size(hf, canfd_ts, 1);
591 else
592 minimum_length = sizeof(hf->header) + data_length;
593 } else {
594 if (hf->echo_id == GS_HOST_FRAME_ECHO_ID_RX &&
595 !(hf->can_id & cpu_to_le32(CAN_RTR_FLAG)))
596 data_length = can_cc_dlc2len(hf->can_dlc);
597
598 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
599 /* timestamp follows data field of max size */
600 minimum_length = struct_size(hf, classic_can_ts, 1);
601 else
602 minimum_length = sizeof(hf->header) + data_length;
603 }
604
605 *data_length_p = data_length;
606 return minimum_length;
607 }
608
gs_usb_receive_bulk_callback(struct urb * urb)609 static void gs_usb_receive_bulk_callback(struct urb *urb)
610 {
611 struct gs_usb *parent = urb->context;
612 struct gs_can *dev;
613 struct net_device *netdev;
614 int rc;
615 struct net_device_stats *stats;
616 struct gs_host_frame *hf = urb->transfer_buffer;
617 unsigned int minimum_length, data_length;
618 struct gs_tx_context *txc;
619 struct can_frame *cf;
620 struct canfd_frame *cfd;
621 struct sk_buff *skb;
622
623 BUG_ON(!parent);
624
625 switch (urb->status) {
626 case 0: /* success */
627 break;
628 case -ENOENT:
629 case -ESHUTDOWN:
630 return;
631 default:
632 /* do not resubmit aborted urbs. eg: when device goes down */
633 return;
634 }
635
636 minimum_length = sizeof(hf->header);
637 if (urb->actual_length < minimum_length) {
638 dev_err_ratelimited(&parent->udev->dev,
639 "short read (actual_length=%u, minimum_length=%u)\n",
640 urb->actual_length, minimum_length);
641
642 goto resubmit_urb;
643 }
644
645 /* device reports out of range channel id */
646 if (hf->channel >= parent->channel_cnt)
647 goto device_detach;
648
649 dev = parent->canch[hf->channel];
650
651 netdev = dev->netdev;
652 stats = &netdev->stats;
653
654 if (!netif_device_present(netdev))
655 return;
656
657 if (!netif_running(netdev))
658 goto resubmit_urb;
659
660 minimum_length = gs_usb_get_minimum_rx_length(dev, hf, &data_length);
661 if (urb->actual_length < minimum_length) {
662 stats->rx_errors++;
663 stats->rx_length_errors++;
664
665 if (net_ratelimit())
666 netdev_err(netdev,
667 "short read (actual_length=%u, minimum_length=%u)\n",
668 urb->actual_length, minimum_length);
669
670 goto resubmit_urb;
671 }
672
673 if (hf->echo_id == GS_HOST_FRAME_ECHO_ID_RX) { /* normal rx */
674 if (hf->flags & GS_CAN_FLAG_FD) {
675 skb = alloc_canfd_skb(netdev, &cfd);
676 if (!skb)
677 return;
678
679 cfd->can_id = le32_to_cpu(hf->can_id);
680 cfd->len = data_length;
681 if (hf->flags & GS_CAN_FLAG_BRS)
682 cfd->flags |= CANFD_BRS;
683 if (hf->flags & GS_CAN_FLAG_ESI)
684 cfd->flags |= CANFD_ESI;
685
686 memcpy(cfd->data, hf->canfd->data, data_length);
687 } else {
688 skb = alloc_can_skb(netdev, &cf);
689 if (!skb)
690 return;
691
692 cf->can_id = le32_to_cpu(hf->can_id);
693 can_frame_set_cc_len(cf, hf->can_dlc, dev->can.ctrlmode);
694
695 memcpy(cf->data, hf->classic_can->data, data_length);
696
697 /* ERROR frames tell us information about the controller */
698 if (le32_to_cpu(hf->can_id) & CAN_ERR_FLAG)
699 gs_update_state(dev, cf);
700 }
701
702 gs_usb_rx_offload(dev, skb, hf);
703 } else { /* echo_id == hf->echo_id */
704 if (hf->echo_id >= GS_MAX_TX_URBS) {
705 netdev_err(netdev,
706 "Unexpected out of range echo id %u\n",
707 hf->echo_id);
708 goto resubmit_urb;
709 }
710
711 txc = gs_get_tx_context(dev, hf->echo_id);
712
713 /* bad devices send bad echo_ids. */
714 if (!txc) {
715 netdev_err(netdev,
716 "Unexpected unused echo id %u\n",
717 hf->echo_id);
718 goto resubmit_urb;
719 }
720
721 skb = dev->can.echo_skb[hf->echo_id];
722 stats->tx_packets++;
723 stats->tx_bytes += gs_usb_get_echo_skb(dev, skb, hf);
724 gs_free_tx_context(txc);
725
726 atomic_dec(&dev->active_tx_urbs);
727
728 netif_wake_queue(netdev);
729 }
730
731 if (hf->flags & GS_CAN_FLAG_OVERFLOW) {
732 stats->rx_over_errors++;
733 stats->rx_errors++;
734
735 skb = alloc_can_err_skb(netdev, &cf);
736 if (!skb)
737 goto resubmit_urb;
738
739 cf->can_id |= CAN_ERR_CRTL;
740 cf->len = CAN_ERR_DLC;
741 cf->data[1] = CAN_ERR_CRTL_RX_OVERFLOW;
742
743 gs_usb_rx_offload(dev, skb, hf);
744 }
745
746 can_rx_offload_irq_finish(&dev->offload);
747
748 resubmit_urb:
749 usb_fill_bulk_urb(urb, parent->udev,
750 parent->pipe_in,
751 hf, parent->hf_size_rx,
752 gs_usb_receive_bulk_callback, parent);
753
754 rc = usb_submit_urb(urb, GFP_ATOMIC);
755
756 /* USB failure take down all interfaces */
757 if (rc == -ENODEV) {
758 device_detach:
759 for (rc = 0; rc < parent->channel_cnt; rc++) {
760 if (parent->canch[rc])
761 netif_device_detach(parent->canch[rc]->netdev);
762 }
763 }
764 }
765
gs_usb_set_bittiming(struct net_device * netdev)766 static int gs_usb_set_bittiming(struct net_device *netdev)
767 {
768 struct gs_can *dev = netdev_priv(netdev);
769 struct can_bittiming *bt = &dev->can.bittiming;
770 struct gs_device_bittiming dbt = {
771 .prop_seg = cpu_to_le32(bt->prop_seg),
772 .phase_seg1 = cpu_to_le32(bt->phase_seg1),
773 .phase_seg2 = cpu_to_le32(bt->phase_seg2),
774 .sjw = cpu_to_le32(bt->sjw),
775 .brp = cpu_to_le32(bt->brp),
776 };
777
778 /* request bit timings */
779 return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_BITTIMING,
780 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
781 dev->channel, 0, &dbt, sizeof(dbt), 1000,
782 GFP_KERNEL);
783 }
784
gs_usb_set_data_bittiming(struct net_device * netdev)785 static int gs_usb_set_data_bittiming(struct net_device *netdev)
786 {
787 struct gs_can *dev = netdev_priv(netdev);
788 struct can_bittiming *bt = &dev->can.fd.data_bittiming;
789 struct gs_device_bittiming dbt = {
790 .prop_seg = cpu_to_le32(bt->prop_seg),
791 .phase_seg1 = cpu_to_le32(bt->phase_seg1),
792 .phase_seg2 = cpu_to_le32(bt->phase_seg2),
793 .sjw = cpu_to_le32(bt->sjw),
794 .brp = cpu_to_le32(bt->brp),
795 };
796 u8 request = GS_USB_BREQ_DATA_BITTIMING;
797
798 if (dev->feature & GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO)
799 request = GS_USB_BREQ_QUIRK_CANTACT_PRO_DATA_BITTIMING;
800
801 /* request data bit timings */
802 return usb_control_msg_send(dev->udev, 0, request,
803 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
804 dev->channel, 0, &dbt, sizeof(dbt), 1000,
805 GFP_KERNEL);
806 }
807
gs_usb_xmit_callback(struct urb * urb)808 static void gs_usb_xmit_callback(struct urb *urb)
809 {
810 struct gs_tx_context *txc = urb->context;
811 struct gs_can *dev = txc->dev;
812 struct net_device *netdev = dev->netdev;
813
814 if (!urb->status)
815 return;
816
817 if (urb->status != -ESHUTDOWN && net_ratelimit())
818 netdev_info(netdev, "failed to xmit URB %u: %pe\n",
819 txc->echo_id, ERR_PTR(urb->status));
820
821 netdev->stats.tx_dropped++;
822 netdev->stats.tx_errors++;
823
824 can_free_echo_skb(netdev, txc->echo_id, NULL);
825 gs_free_tx_context(txc);
826 atomic_dec(&dev->active_tx_urbs);
827
828 netif_wake_queue(netdev);
829 }
830
gs_can_start_xmit(struct sk_buff * skb,struct net_device * netdev)831 static netdev_tx_t gs_can_start_xmit(struct sk_buff *skb,
832 struct net_device *netdev)
833 {
834 struct gs_can *dev = netdev_priv(netdev);
835 struct net_device_stats *stats = &dev->netdev->stats;
836 struct urb *urb;
837 struct gs_host_frame *hf;
838 struct can_frame *cf;
839 struct canfd_frame *cfd;
840 int rc;
841 unsigned int idx;
842 struct gs_tx_context *txc;
843
844 if (can_dev_dropped_skb(netdev, skb))
845 return NETDEV_TX_OK;
846
847 /* find an empty context to keep track of transmission */
848 txc = gs_alloc_tx_context(dev);
849 if (!txc)
850 return NETDEV_TX_BUSY;
851
852 /* create a URB, and a buffer for it */
853 urb = usb_alloc_urb(0, GFP_ATOMIC);
854 if (!urb)
855 goto nomem_urb;
856
857 hf = kmalloc(dev->hf_size_tx, GFP_ATOMIC);
858 if (!hf)
859 goto nomem_hf;
860
861 idx = txc->echo_id;
862
863 if (idx >= GS_MAX_TX_URBS) {
864 netdev_err(netdev, "Invalid tx context %u\n", idx);
865 goto badidx;
866 }
867
868 hf->echo_id = idx;
869 hf->channel = dev->channel;
870 hf->flags = 0;
871 hf->reserved = 0;
872
873 if (can_is_canfd_skb(skb)) {
874 cfd = (struct canfd_frame *)skb->data;
875
876 hf->can_id = cpu_to_le32(cfd->can_id);
877 hf->can_dlc = can_fd_len2dlc(cfd->len);
878 hf->flags |= GS_CAN_FLAG_FD;
879 if (cfd->flags & CANFD_BRS)
880 hf->flags |= GS_CAN_FLAG_BRS;
881 if (cfd->flags & CANFD_ESI)
882 hf->flags |= GS_CAN_FLAG_ESI;
883
884 memcpy(hf->canfd->data, cfd->data, cfd->len);
885 } else {
886 cf = (struct can_frame *)skb->data;
887
888 hf->can_id = cpu_to_le32(cf->can_id);
889 hf->can_dlc = can_get_cc_dlc(cf, dev->can.ctrlmode);
890
891 memcpy(hf->classic_can->data, cf->data, cf->len);
892 }
893
894 usb_fill_bulk_urb(urb, dev->udev,
895 dev->parent->pipe_out,
896 hf, dev->hf_size_tx,
897 gs_usb_xmit_callback, txc);
898
899 urb->transfer_flags |= URB_FREE_BUFFER;
900 usb_anchor_urb(urb, &dev->tx_submitted);
901
902 can_put_echo_skb(skb, netdev, idx, 0);
903
904 atomic_inc(&dev->active_tx_urbs);
905
906 rc = usb_submit_urb(urb, GFP_ATOMIC);
907 if (unlikely(rc)) { /* usb send failed */
908 atomic_dec(&dev->active_tx_urbs);
909
910 can_free_echo_skb(netdev, idx, NULL);
911 gs_free_tx_context(txc);
912
913 usb_unanchor_urb(urb);
914
915 if (rc == -ENODEV) {
916 netif_device_detach(netdev);
917 } else {
918 netdev_err(netdev, "usb_submit failed (err=%d)\n", rc);
919 stats->tx_dropped++;
920 }
921 } else {
922 /* Slow down tx path */
923 if (atomic_read(&dev->active_tx_urbs) >= GS_MAX_TX_URBS)
924 netif_stop_queue(netdev);
925 }
926
927 /* let usb core take care of this urb */
928 usb_free_urb(urb);
929
930 return NETDEV_TX_OK;
931
932 badidx:
933 kfree(hf);
934 nomem_hf:
935 usb_free_urb(urb);
936
937 nomem_urb:
938 gs_free_tx_context(txc);
939 dev_kfree_skb(skb);
940 stats->tx_dropped++;
941 return NETDEV_TX_OK;
942 }
943
gs_can_open(struct net_device * netdev)944 static int gs_can_open(struct net_device *netdev)
945 {
946 struct gs_can *dev = netdev_priv(netdev);
947 struct gs_usb *parent = dev->parent;
948 struct gs_device_mode dm = {
949 .mode = cpu_to_le32(GS_CAN_MODE_START),
950 };
951 struct gs_host_frame *hf;
952 struct urb *urb = NULL;
953 u32 ctrlmode;
954 u32 flags = 0;
955 int rc, i;
956
957 rc = open_candev(netdev);
958 if (rc)
959 return rc;
960
961 ctrlmode = dev->can.ctrlmode;
962 if (ctrlmode & CAN_CTRLMODE_FD) {
963 if (dev->feature & GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX)
964 dev->hf_size_tx = struct_size(hf, canfd_quirk, 1);
965 else
966 dev->hf_size_tx = struct_size(hf, canfd, 1);
967 } else {
968 if (dev->feature & GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX)
969 dev->hf_size_tx = struct_size(hf, classic_can_quirk, 1);
970 else
971 dev->hf_size_tx = struct_size(hf, classic_can, 1);
972 }
973
974 can_rx_offload_enable(&dev->offload);
975
976 if (!parent->active_channels) {
977 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
978 gs_usb_timestamp_init(parent);
979
980 for (i = 0; i < GS_MAX_RX_URBS; i++) {
981 u8 *buf;
982
983 /* alloc rx urb */
984 urb = usb_alloc_urb(0, GFP_KERNEL);
985 if (!urb) {
986 rc = -ENOMEM;
987 goto out_usb_kill_anchored_urbs;
988 }
989
990 /* alloc rx buffer */
991 buf = kmalloc(dev->parent->hf_size_rx,
992 GFP_KERNEL);
993 if (!buf) {
994 rc = -ENOMEM;
995 goto out_usb_free_urb;
996 }
997
998 /* fill, anchor, and submit rx urb */
999 usb_fill_bulk_urb(urb,
1000 dev->udev,
1001 dev->parent->pipe_in,
1002 buf,
1003 dev->parent->hf_size_rx,
1004 gs_usb_receive_bulk_callback, parent);
1005 urb->transfer_flags |= URB_FREE_BUFFER;
1006
1007 usb_anchor_urb(urb, &parent->rx_submitted);
1008
1009 rc = usb_submit_urb(urb, GFP_KERNEL);
1010 if (rc) {
1011 if (rc == -ENODEV)
1012 netif_device_detach(dev->netdev);
1013
1014 netdev_err(netdev,
1015 "usb_submit_urb() failed, error %pe\n",
1016 ERR_PTR(rc));
1017
1018 goto out_usb_unanchor_urb;
1019 }
1020
1021 /* Drop reference,
1022 * USB core will take care of freeing it
1023 */
1024 usb_free_urb(urb);
1025 }
1026 }
1027
1028 /* flags */
1029 if (ctrlmode & CAN_CTRLMODE_LOOPBACK)
1030 flags |= GS_CAN_MODE_LOOP_BACK;
1031
1032 if (ctrlmode & CAN_CTRLMODE_LISTENONLY)
1033 flags |= GS_CAN_MODE_LISTEN_ONLY;
1034
1035 if (ctrlmode & CAN_CTRLMODE_3_SAMPLES)
1036 flags |= GS_CAN_MODE_TRIPLE_SAMPLE;
1037
1038 if (ctrlmode & CAN_CTRLMODE_ONE_SHOT)
1039 flags |= GS_CAN_MODE_ONE_SHOT;
1040
1041 if (ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
1042 flags |= GS_CAN_MODE_BERR_REPORTING;
1043
1044 if (ctrlmode & CAN_CTRLMODE_FD)
1045 flags |= GS_CAN_MODE_FD;
1046
1047 /* if hardware supports timestamps, enable it */
1048 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1049 flags |= GS_CAN_MODE_HW_TIMESTAMP;
1050
1051 /* finally start device */
1052 dev->can.state = CAN_STATE_ERROR_ACTIVE;
1053 dm.flags = cpu_to_le32(flags);
1054 rc = usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_MODE,
1055 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1056 dev->channel, 0, &dm, sizeof(dm), 1000,
1057 GFP_KERNEL);
1058 if (rc) {
1059 netdev_err(netdev, "Couldn't start device (err=%d)\n", rc);
1060 dev->can.state = CAN_STATE_STOPPED;
1061
1062 goto out_usb_kill_anchored_urbs;
1063 }
1064
1065 parent->active_channels++;
1066 if (!(dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY))
1067 netif_start_queue(netdev);
1068
1069 return 0;
1070
1071 out_usb_unanchor_urb:
1072 usb_unanchor_urb(urb);
1073 out_usb_free_urb:
1074 usb_free_urb(urb);
1075 out_usb_kill_anchored_urbs:
1076 if (!parent->active_channels) {
1077 usb_kill_anchored_urbs(&dev->tx_submitted);
1078
1079 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1080 gs_usb_timestamp_stop(parent);
1081 }
1082
1083 can_rx_offload_disable(&dev->offload);
1084 close_candev(netdev);
1085
1086 return rc;
1087 }
1088
gs_usb_get_state(const struct net_device * netdev,struct can_berr_counter * bec,enum can_state * state)1089 static int gs_usb_get_state(const struct net_device *netdev,
1090 struct can_berr_counter *bec,
1091 enum can_state *state)
1092 {
1093 struct gs_can *dev = netdev_priv(netdev);
1094 struct gs_device_state ds;
1095 int rc;
1096
1097 rc = usb_control_msg_recv(dev->udev, 0, GS_USB_BREQ_GET_STATE,
1098 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1099 dev->channel, 0,
1100 &ds, sizeof(ds),
1101 USB_CTRL_GET_TIMEOUT,
1102 GFP_KERNEL);
1103 if (rc)
1104 return rc;
1105
1106 if (le32_to_cpu(ds.state) >= CAN_STATE_MAX)
1107 return -EOPNOTSUPP;
1108
1109 *state = le32_to_cpu(ds.state);
1110 bec->txerr = le32_to_cpu(ds.txerr);
1111 bec->rxerr = le32_to_cpu(ds.rxerr);
1112
1113 return 0;
1114 }
1115
gs_usb_can_get_berr_counter(const struct net_device * netdev,struct can_berr_counter * bec)1116 static int gs_usb_can_get_berr_counter(const struct net_device *netdev,
1117 struct can_berr_counter *bec)
1118 {
1119 enum can_state state;
1120
1121 return gs_usb_get_state(netdev, bec, &state);
1122 }
1123
gs_can_close(struct net_device * netdev)1124 static int gs_can_close(struct net_device *netdev)
1125 {
1126 int rc;
1127 struct gs_can *dev = netdev_priv(netdev);
1128 struct gs_usb *parent = dev->parent;
1129
1130 netif_stop_queue(netdev);
1131
1132 /* Stop polling */
1133 parent->active_channels--;
1134 if (!parent->active_channels) {
1135 usb_kill_anchored_urbs(&parent->rx_submitted);
1136
1137 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1138 gs_usb_timestamp_stop(parent);
1139 }
1140
1141 /* Stop sending URBs */
1142 usb_kill_anchored_urbs(&dev->tx_submitted);
1143 atomic_set(&dev->active_tx_urbs, 0);
1144
1145 dev->can.state = CAN_STATE_STOPPED;
1146
1147 /* reset the device */
1148 gs_cmd_reset(dev);
1149
1150 /* reset tx contexts */
1151 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) {
1152 dev->tx_context[rc].dev = dev;
1153 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS;
1154 }
1155
1156 can_rx_offload_disable(&dev->offload);
1157
1158 /* close the netdev */
1159 close_candev(netdev);
1160
1161 return 0;
1162 }
1163
gs_can_eth_ioctl(struct net_device * netdev,struct ifreq * ifr,int cmd)1164 static int gs_can_eth_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
1165 {
1166 const struct gs_can *dev = netdev_priv(netdev);
1167
1168 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1169 return can_eth_ioctl_hwts(netdev, ifr, cmd);
1170
1171 return -EOPNOTSUPP;
1172 }
1173
1174 static const struct net_device_ops gs_usb_netdev_ops = {
1175 .ndo_open = gs_can_open,
1176 .ndo_stop = gs_can_close,
1177 .ndo_start_xmit = gs_can_start_xmit,
1178 .ndo_change_mtu = can_change_mtu,
1179 .ndo_eth_ioctl = gs_can_eth_ioctl,
1180 };
1181
gs_usb_set_identify(struct net_device * netdev,bool do_identify)1182 static int gs_usb_set_identify(struct net_device *netdev, bool do_identify)
1183 {
1184 struct gs_can *dev = netdev_priv(netdev);
1185 struct gs_identify_mode imode;
1186
1187 if (do_identify)
1188 imode.mode = cpu_to_le32(GS_CAN_IDENTIFY_ON);
1189 else
1190 imode.mode = cpu_to_le32(GS_CAN_IDENTIFY_OFF);
1191
1192 return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_IDENTIFY,
1193 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1194 dev->channel, 0, &imode, sizeof(imode), 100,
1195 GFP_KERNEL);
1196 }
1197
1198 /* blink LED's for finding the this interface */
gs_usb_set_phys_id(struct net_device * netdev,enum ethtool_phys_id_state state)1199 static int gs_usb_set_phys_id(struct net_device *netdev,
1200 enum ethtool_phys_id_state state)
1201 {
1202 const struct gs_can *dev = netdev_priv(netdev);
1203 int rc = 0;
1204
1205 if (!(dev->feature & GS_CAN_FEATURE_IDENTIFY))
1206 return -EOPNOTSUPP;
1207
1208 switch (state) {
1209 case ETHTOOL_ID_ACTIVE:
1210 rc = gs_usb_set_identify(netdev, GS_CAN_IDENTIFY_ON);
1211 break;
1212 case ETHTOOL_ID_INACTIVE:
1213 rc = gs_usb_set_identify(netdev, GS_CAN_IDENTIFY_OFF);
1214 break;
1215 default:
1216 break;
1217 }
1218
1219 return rc;
1220 }
1221
gs_usb_get_ts_info(struct net_device * netdev,struct kernel_ethtool_ts_info * info)1222 static int gs_usb_get_ts_info(struct net_device *netdev,
1223 struct kernel_ethtool_ts_info *info)
1224 {
1225 struct gs_can *dev = netdev_priv(netdev);
1226
1227 /* report if device supports HW timestamps */
1228 if (dev->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1229 return can_ethtool_op_get_ts_info_hwts(netdev, info);
1230
1231 return ethtool_op_get_ts_info(netdev, info);
1232 }
1233
1234 static const struct ethtool_ops gs_usb_ethtool_ops = {
1235 .set_phys_id = gs_usb_set_phys_id,
1236 .get_ts_info = gs_usb_get_ts_info,
1237 };
1238
gs_usb_get_termination(struct net_device * netdev,u16 * term)1239 static int gs_usb_get_termination(struct net_device *netdev, u16 *term)
1240 {
1241 struct gs_can *dev = netdev_priv(netdev);
1242 struct gs_device_termination_state term_state;
1243 int rc;
1244
1245 rc = usb_control_msg_recv(dev->udev, 0, GS_USB_BREQ_GET_TERMINATION,
1246 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1247 dev->channel, 0,
1248 &term_state, sizeof(term_state), 1000,
1249 GFP_KERNEL);
1250 if (rc)
1251 return rc;
1252
1253 if (term_state.state == cpu_to_le32(GS_CAN_TERMINATION_STATE_ON))
1254 *term = GS_USB_TERMINATION_ENABLED;
1255 else
1256 *term = GS_USB_TERMINATION_DISABLED;
1257
1258 return 0;
1259 }
1260
gs_usb_set_termination(struct net_device * netdev,u16 term)1261 static int gs_usb_set_termination(struct net_device *netdev, u16 term)
1262 {
1263 struct gs_can *dev = netdev_priv(netdev);
1264 struct gs_device_termination_state term_state;
1265
1266 if (term == GS_USB_TERMINATION_ENABLED)
1267 term_state.state = cpu_to_le32(GS_CAN_TERMINATION_STATE_ON);
1268 else
1269 term_state.state = cpu_to_le32(GS_CAN_TERMINATION_STATE_OFF);
1270
1271 return usb_control_msg_send(dev->udev, 0, GS_USB_BREQ_SET_TERMINATION,
1272 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1273 dev->channel, 0,
1274 &term_state, sizeof(term_state), 1000,
1275 GFP_KERNEL);
1276 }
1277
1278 static const u16 gs_usb_termination_const[] = {
1279 GS_USB_TERMINATION_DISABLED,
1280 GS_USB_TERMINATION_ENABLED
1281 };
1282
gs_make_candev(unsigned int channel,struct usb_interface * intf,struct gs_device_config * dconf)1283 static struct gs_can *gs_make_candev(unsigned int channel,
1284 struct usb_interface *intf,
1285 struct gs_device_config *dconf)
1286 {
1287 struct gs_can *dev;
1288 struct net_device *netdev;
1289 int rc;
1290 struct gs_device_bt_const_extended bt_const_extended;
1291 struct gs_device_bt_const bt_const;
1292 u32 feature;
1293
1294 /* fetch bit timing constants */
1295 rc = usb_control_msg_recv(interface_to_usbdev(intf), 0,
1296 GS_USB_BREQ_BT_CONST,
1297 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1298 channel, 0, &bt_const, sizeof(bt_const), 1000,
1299 GFP_KERNEL);
1300
1301 if (rc) {
1302 dev_err(&intf->dev,
1303 "Couldn't get bit timing const for channel %d (%pe)\n",
1304 channel, ERR_PTR(rc));
1305 return ERR_PTR(rc);
1306 }
1307
1308 /* create netdev */
1309 netdev = alloc_candev(sizeof(struct gs_can), GS_MAX_TX_URBS);
1310 if (!netdev) {
1311 dev_err(&intf->dev, "Couldn't allocate candev\n");
1312 return ERR_PTR(-ENOMEM);
1313 }
1314
1315 dev = netdev_priv(netdev);
1316
1317 netdev->netdev_ops = &gs_usb_netdev_ops;
1318 netdev->ethtool_ops = &gs_usb_ethtool_ops;
1319
1320 netdev->flags |= IFF_ECHO; /* we support full roundtrip echo */
1321 netdev->dev_id = channel;
1322 netdev->dev_port = channel;
1323
1324 /* dev setup */
1325 strcpy(dev->bt_const.name, KBUILD_MODNAME);
1326 dev->bt_const.tseg1_min = le32_to_cpu(bt_const.tseg1_min);
1327 dev->bt_const.tseg1_max = le32_to_cpu(bt_const.tseg1_max);
1328 dev->bt_const.tseg2_min = le32_to_cpu(bt_const.tseg2_min);
1329 dev->bt_const.tseg2_max = le32_to_cpu(bt_const.tseg2_max);
1330 dev->bt_const.sjw_max = le32_to_cpu(bt_const.sjw_max);
1331 dev->bt_const.brp_min = le32_to_cpu(bt_const.brp_min);
1332 dev->bt_const.brp_max = le32_to_cpu(bt_const.brp_max);
1333 dev->bt_const.brp_inc = le32_to_cpu(bt_const.brp_inc);
1334
1335 dev->udev = interface_to_usbdev(intf);
1336 dev->netdev = netdev;
1337 dev->channel = channel;
1338
1339 init_usb_anchor(&dev->tx_submitted);
1340 atomic_set(&dev->active_tx_urbs, 0);
1341 spin_lock_init(&dev->tx_ctx_lock);
1342 for (rc = 0; rc < GS_MAX_TX_URBS; rc++) {
1343 dev->tx_context[rc].dev = dev;
1344 dev->tx_context[rc].echo_id = GS_MAX_TX_URBS;
1345 }
1346
1347 /* can setup */
1348 dev->can.state = CAN_STATE_STOPPED;
1349 dev->can.clock.freq = le32_to_cpu(bt_const.fclk_can);
1350 dev->can.bittiming_const = &dev->bt_const;
1351 dev->can.do_set_bittiming = gs_usb_set_bittiming;
1352
1353 dev->can.ctrlmode_supported = CAN_CTRLMODE_CC_LEN8_DLC;
1354
1355 feature = le32_to_cpu(bt_const.feature);
1356 dev->feature = FIELD_GET(GS_CAN_FEATURE_MASK, feature);
1357 if (feature & GS_CAN_FEATURE_LISTEN_ONLY)
1358 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LISTENONLY;
1359
1360 if (feature & GS_CAN_FEATURE_LOOP_BACK)
1361 dev->can.ctrlmode_supported |= CAN_CTRLMODE_LOOPBACK;
1362
1363 if (feature & GS_CAN_FEATURE_TRIPLE_SAMPLE)
1364 dev->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
1365
1366 if (feature & GS_CAN_FEATURE_ONE_SHOT)
1367 dev->can.ctrlmode_supported |= CAN_CTRLMODE_ONE_SHOT;
1368
1369 if (feature & GS_CAN_FEATURE_FD) {
1370 dev->can.ctrlmode_supported |= CAN_CTRLMODE_FD;
1371 /* The data bit timing will be overwritten, if
1372 * GS_CAN_FEATURE_BT_CONST_EXT is set.
1373 */
1374 dev->can.fd.data_bittiming_const = &dev->bt_const;
1375 dev->can.fd.do_set_data_bittiming = gs_usb_set_data_bittiming;
1376 }
1377
1378 if (feature & GS_CAN_FEATURE_TERMINATION) {
1379 rc = gs_usb_get_termination(netdev, &dev->can.termination);
1380 if (rc) {
1381 dev->feature &= ~GS_CAN_FEATURE_TERMINATION;
1382
1383 dev_info(&intf->dev,
1384 "Disabling termination support for channel %d (%pe)\n",
1385 channel, ERR_PTR(rc));
1386 } else {
1387 dev->can.termination_const = gs_usb_termination_const;
1388 dev->can.termination_const_cnt = ARRAY_SIZE(gs_usb_termination_const);
1389 dev->can.do_set_termination = gs_usb_set_termination;
1390 }
1391 }
1392
1393 if (feature & GS_CAN_FEATURE_BERR_REPORTING)
1394 dev->can.ctrlmode_supported |= CAN_CTRLMODE_BERR_REPORTING;
1395
1396 if (feature & GS_CAN_FEATURE_GET_STATE)
1397 dev->can.do_get_berr_counter = gs_usb_can_get_berr_counter;
1398
1399 /* The CANtact Pro from LinkLayer Labs is based on the
1400 * LPC54616 µC, which is affected by the NXP LPC USB transfer
1401 * erratum. However, the current firmware (version 2) doesn't
1402 * set the GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX bit. Set the
1403 * feature GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX to workaround
1404 * this issue.
1405 *
1406 * For the GS_USB_BREQ_DATA_BITTIMING USB control message the
1407 * CANtact Pro firmware uses a request value, which is already
1408 * used by the candleLight firmware for a different purpose
1409 * (GS_USB_BREQ_GET_USER_ID). Set the feature
1410 * GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO to workaround this
1411 * issue.
1412 */
1413 if (dev->udev->descriptor.idVendor == cpu_to_le16(USB_GS_USB_1_VENDOR_ID) &&
1414 dev->udev->descriptor.idProduct == cpu_to_le16(USB_GS_USB_1_PRODUCT_ID) &&
1415 dev->udev->manufacturer && dev->udev->product &&
1416 !strcmp(dev->udev->manufacturer, "LinkLayer Labs") &&
1417 !strcmp(dev->udev->product, "CANtact Pro") &&
1418 (le32_to_cpu(dconf->sw_version) <= 2))
1419 dev->feature |= GS_CAN_FEATURE_REQ_USB_QUIRK_LPC546XX |
1420 GS_CAN_FEATURE_QUIRK_BREQ_CANTACT_PRO;
1421
1422 /* GS_CAN_FEATURE_IDENTIFY is only supported for sw_version > 1 */
1423 if (!(le32_to_cpu(dconf->sw_version) > 1 &&
1424 feature & GS_CAN_FEATURE_IDENTIFY))
1425 dev->feature &= ~GS_CAN_FEATURE_IDENTIFY;
1426
1427 /* fetch extended bit timing constants if device has feature
1428 * GS_CAN_FEATURE_FD and GS_CAN_FEATURE_BT_CONST_EXT
1429 */
1430 if (feature & GS_CAN_FEATURE_FD &&
1431 feature & GS_CAN_FEATURE_BT_CONST_EXT) {
1432 rc = usb_control_msg_recv(interface_to_usbdev(intf), 0,
1433 GS_USB_BREQ_BT_CONST_EXT,
1434 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1435 channel, 0, &bt_const_extended,
1436 sizeof(bt_const_extended),
1437 1000, GFP_KERNEL);
1438 if (rc) {
1439 dev_err(&intf->dev,
1440 "Couldn't get extended bit timing const for channel %d (%pe)\n",
1441 channel, ERR_PTR(rc));
1442 goto out_free_candev;
1443 }
1444
1445 strcpy(dev->data_bt_const.name, KBUILD_MODNAME);
1446 dev->data_bt_const.tseg1_min = le32_to_cpu(bt_const_extended.dtseg1_min);
1447 dev->data_bt_const.tseg1_max = le32_to_cpu(bt_const_extended.dtseg1_max);
1448 dev->data_bt_const.tseg2_min = le32_to_cpu(bt_const_extended.dtseg2_min);
1449 dev->data_bt_const.tseg2_max = le32_to_cpu(bt_const_extended.dtseg2_max);
1450 dev->data_bt_const.sjw_max = le32_to_cpu(bt_const_extended.dsjw_max);
1451 dev->data_bt_const.brp_min = le32_to_cpu(bt_const_extended.dbrp_min);
1452 dev->data_bt_const.brp_max = le32_to_cpu(bt_const_extended.dbrp_max);
1453 dev->data_bt_const.brp_inc = le32_to_cpu(bt_const_extended.dbrp_inc);
1454
1455 dev->can.fd.data_bittiming_const = &dev->data_bt_const;
1456 }
1457
1458 can_rx_offload_add_manual(netdev, &dev->offload, GS_NAPI_WEIGHT);
1459 SET_NETDEV_DEV(netdev, &intf->dev);
1460
1461 rc = register_candev(dev->netdev);
1462 if (rc) {
1463 dev_err(&intf->dev,
1464 "Couldn't register candev for channel %d (%pe)\n",
1465 channel, ERR_PTR(rc));
1466 goto out_can_rx_offload_del;
1467 }
1468
1469 return dev;
1470
1471 out_can_rx_offload_del:
1472 can_rx_offload_del(&dev->offload);
1473 out_free_candev:
1474 free_candev(dev->netdev);
1475 return ERR_PTR(rc);
1476 }
1477
gs_destroy_candev(struct gs_can * dev)1478 static void gs_destroy_candev(struct gs_can *dev)
1479 {
1480 unregister_candev(dev->netdev);
1481 can_rx_offload_del(&dev->offload);
1482 free_candev(dev->netdev);
1483 }
1484
gs_usb_probe(struct usb_interface * intf,const struct usb_device_id * id)1485 static int gs_usb_probe(struct usb_interface *intf,
1486 const struct usb_device_id *id)
1487 {
1488 struct usb_device *udev = interface_to_usbdev(intf);
1489 struct usb_endpoint_descriptor *ep_in, *ep_out;
1490 struct gs_host_frame *hf;
1491 struct gs_usb *parent;
1492 struct gs_host_config hconf = {
1493 .byte_order = cpu_to_le32(0x0000beef),
1494 };
1495 struct gs_device_config dconf;
1496 unsigned int icount, i;
1497 int rc;
1498
1499 rc = usb_find_common_endpoints(intf->cur_altsetting,
1500 &ep_in, &ep_out, NULL, NULL);
1501 if (rc) {
1502 dev_err(&intf->dev, "Required endpoints not found\n");
1503 return rc;
1504 }
1505
1506 /* send host config */
1507 rc = usb_control_msg_send(udev, 0,
1508 GS_USB_BREQ_HOST_FORMAT,
1509 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1510 1, intf->cur_altsetting->desc.bInterfaceNumber,
1511 &hconf, sizeof(hconf), 1000,
1512 GFP_KERNEL);
1513 if (rc) {
1514 dev_err(&intf->dev, "Couldn't send data format (err=%d)\n", rc);
1515 return rc;
1516 }
1517
1518 /* read device config */
1519 rc = usb_control_msg_recv(udev, 0,
1520 GS_USB_BREQ_DEVICE_CONFIG,
1521 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
1522 1, intf->cur_altsetting->desc.bInterfaceNumber,
1523 &dconf, sizeof(dconf), 1000,
1524 GFP_KERNEL);
1525 if (rc) {
1526 dev_err(&intf->dev, "Couldn't get device config: (err=%d)\n",
1527 rc);
1528 return rc;
1529 }
1530
1531 icount = dconf.icount + 1;
1532 dev_info(&intf->dev, "Configuring for %u interfaces\n", icount);
1533
1534 if (icount > type_max(parent->channel_cnt)) {
1535 dev_err(&intf->dev,
1536 "Driver cannot handle more that %u CAN interfaces\n",
1537 type_max(parent->channel_cnt));
1538 return -EINVAL;
1539 }
1540
1541 parent = kzalloc(struct_size(parent, canch, icount), GFP_KERNEL);
1542 if (!parent)
1543 return -ENOMEM;
1544
1545 parent->channel_cnt = icount;
1546
1547 init_usb_anchor(&parent->rx_submitted);
1548
1549 usb_set_intfdata(intf, parent);
1550 parent->udev = udev;
1551
1552 /* store the detected endpoints */
1553 parent->pipe_in = usb_rcvbulkpipe(parent->udev, ep_in->bEndpointAddress);
1554 parent->pipe_out = usb_sndbulkpipe(parent->udev, ep_out->bEndpointAddress);
1555
1556 for (i = 0; i < icount; i++) {
1557 unsigned int hf_size_rx = 0;
1558
1559 parent->canch[i] = gs_make_candev(i, intf, &dconf);
1560 if (IS_ERR_OR_NULL(parent->canch[i])) {
1561 /* save error code to return later */
1562 rc = PTR_ERR(parent->canch[i]);
1563
1564 /* on failure destroy previously created candevs */
1565 icount = i;
1566 for (i = 0; i < icount; i++)
1567 gs_destroy_candev(parent->canch[i]);
1568
1569 usb_kill_anchored_urbs(&parent->rx_submitted);
1570 kfree(parent);
1571 return rc;
1572 }
1573 parent->canch[i]->parent = parent;
1574
1575 /* set RX packet size based on FD and if hardware
1576 * timestamps are supported.
1577 */
1578 if (parent->canch[i]->can.ctrlmode_supported & CAN_CTRLMODE_FD) {
1579 if (parent->canch[i]->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1580 hf_size_rx = struct_size(hf, canfd_ts, 1);
1581 else
1582 hf_size_rx = struct_size(hf, canfd, 1);
1583 } else {
1584 if (parent->canch[i]->feature & GS_CAN_FEATURE_HW_TIMESTAMP)
1585 hf_size_rx = struct_size(hf, classic_can_ts, 1);
1586 else
1587 hf_size_rx = struct_size(hf, classic_can, 1);
1588 }
1589 parent->hf_size_rx = max(parent->hf_size_rx, hf_size_rx);
1590 }
1591
1592 return 0;
1593 }
1594
gs_usb_disconnect(struct usb_interface * intf)1595 static void gs_usb_disconnect(struct usb_interface *intf)
1596 {
1597 struct gs_usb *parent = usb_get_intfdata(intf);
1598 unsigned int i;
1599
1600 usb_set_intfdata(intf, NULL);
1601
1602 if (!parent) {
1603 dev_err(&intf->dev, "Disconnect (nodata)\n");
1604 return;
1605 }
1606
1607 for (i = 0; i < parent->channel_cnt; i++)
1608 if (parent->canch[i])
1609 gs_destroy_candev(parent->canch[i]);
1610
1611 kfree(parent);
1612 }
1613
1614 static const struct usb_device_id gs_usb_table[] = {
1615 { USB_DEVICE_INTERFACE_NUMBER(USB_GS_USB_1_VENDOR_ID,
1616 USB_GS_USB_1_PRODUCT_ID, 0) },
1617 { USB_DEVICE_INTERFACE_NUMBER(USB_CANDLELIGHT_VENDOR_ID,
1618 USB_CANDLELIGHT_PRODUCT_ID, 0) },
1619 { USB_DEVICE_INTERFACE_NUMBER(USB_CES_CANEXT_FD_VENDOR_ID,
1620 USB_CES_CANEXT_FD_PRODUCT_ID, 0) },
1621 { USB_DEVICE_INTERFACE_NUMBER(USB_ABE_CANDEBUGGER_FD_VENDOR_ID,
1622 USB_ABE_CANDEBUGGER_FD_PRODUCT_ID, 0) },
1623 { USB_DEVICE_INTERFACE_NUMBER(USB_XYLANTA_SAINT3_VENDOR_ID,
1624 USB_XYLANTA_SAINT3_PRODUCT_ID, 0) },
1625 { USB_DEVICE_INTERFACE_NUMBER(USB_CANNECTIVITY_VENDOR_ID,
1626 USB_CANNECTIVITY_PRODUCT_ID, 0) },
1627 {} /* Terminating entry */
1628 };
1629
1630 MODULE_DEVICE_TABLE(usb, gs_usb_table);
1631
1632 static struct usb_driver gs_usb_driver = {
1633 .name = KBUILD_MODNAME,
1634 .probe = gs_usb_probe,
1635 .disconnect = gs_usb_disconnect,
1636 .id_table = gs_usb_table,
1637 };
1638
1639 module_usb_driver(gs_usb_driver);
1640
1641 MODULE_AUTHOR("Maximilian Schneider <mws@schneidersoft.net>");
1642 MODULE_DESCRIPTION(
1643 "Socket CAN device driver for Geschwister Schneider Technologie-, "
1644 "Entwicklungs- und Vertriebs UG. USB2.0 to CAN interfaces\n"
1645 "and bytewerk.org candleLight USB CAN interfaces.");
1646 MODULE_LICENSE("GPL v2");
1647