1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Freescale QMC HDLC Device Driver
4 *
5 * Copyright 2023 CS GROUP France
6 *
7 * Author: Herve Codina <herve.codina@bootlin.com>
8 */
9
10 #include <linux/array_size.h>
11 #include <linux/bug.h>
12 #include <linux/cleanup.h>
13 #include <linux/bitmap.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/device.h>
16 #include <linux/err.h>
17 #include <linux/framer/framer.h>
18 #include <linux/hdlc.h>
19 #include <linux/mod_devicetable.h>
20 #include <linux/module.h>
21 #include <linux/mutex.h>
22 #include <linux/platform_device.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 #include <linux/types.h>
26
27 #include <soc/fsl/qe/qmc.h>
28
29 struct qmc_hdlc_desc {
30 struct net_device *netdev;
31 struct sk_buff *skb; /* NULL if the descriptor is not in use */
32 dma_addr_t dma_addr;
33 size_t dma_size;
34 };
35
36 struct qmc_hdlc {
37 struct device *dev;
38 struct qmc_chan *qmc_chan;
39 struct net_device *netdev;
40 struct framer *framer;
41 struct mutex carrier_lock; /* Protect carrier detection */
42 struct notifier_block nb;
43 bool is_crc32;
44 spinlock_t tx_lock; /* Protect tx descriptors */
45 struct qmc_hdlc_desc tx_descs[8];
46 unsigned int tx_out;
47 struct qmc_hdlc_desc rx_descs[4];
48 u32 slot_map;
49 };
50
netdev_to_qmc_hdlc(struct net_device * netdev)51 static struct qmc_hdlc *netdev_to_qmc_hdlc(struct net_device *netdev)
52 {
53 return dev_to_hdlc(netdev)->priv;
54 }
55
qmc_hdlc_framer_set_carrier(struct qmc_hdlc * qmc_hdlc)56 static int qmc_hdlc_framer_set_carrier(struct qmc_hdlc *qmc_hdlc)
57 {
58 struct framer_status framer_status;
59 int ret;
60
61 if (!qmc_hdlc->framer)
62 return 0;
63
64 guard(mutex)(&qmc_hdlc->carrier_lock);
65
66 ret = framer_get_status(qmc_hdlc->framer, &framer_status);
67 if (ret) {
68 dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
69 return ret;
70 }
71 if (framer_status.link_is_on)
72 netif_carrier_on(qmc_hdlc->netdev);
73 else
74 netif_carrier_off(qmc_hdlc->netdev);
75
76 return 0;
77 }
78
qmc_hdlc_framer_notifier(struct notifier_block * nb,unsigned long action,void * data)79 static int qmc_hdlc_framer_notifier(struct notifier_block *nb, unsigned long action,
80 void *data)
81 {
82 struct qmc_hdlc *qmc_hdlc = container_of(nb, struct qmc_hdlc, nb);
83 int ret;
84
85 if (action != FRAMER_EVENT_STATUS)
86 return NOTIFY_DONE;
87
88 ret = qmc_hdlc_framer_set_carrier(qmc_hdlc);
89 return ret ? NOTIFY_DONE : NOTIFY_OK;
90 }
91
qmc_hdlc_framer_start(struct qmc_hdlc * qmc_hdlc)92 static int qmc_hdlc_framer_start(struct qmc_hdlc *qmc_hdlc)
93 {
94 struct framer_status framer_status;
95 int ret;
96
97 if (!qmc_hdlc->framer)
98 return 0;
99
100 ret = framer_power_on(qmc_hdlc->framer);
101 if (ret) {
102 dev_err(qmc_hdlc->dev, "framer power-on failed (%d)\n", ret);
103 return ret;
104 }
105
106 /* Be sure that get_status is supported */
107 ret = framer_get_status(qmc_hdlc->framer, &framer_status);
108 if (ret) {
109 dev_err(qmc_hdlc->dev, "get framer status failed (%d)\n", ret);
110 goto framer_power_off;
111 }
112
113 qmc_hdlc->nb.notifier_call = qmc_hdlc_framer_notifier;
114 ret = framer_notifier_register(qmc_hdlc->framer, &qmc_hdlc->nb);
115 if (ret) {
116 dev_err(qmc_hdlc->dev, "framer notifier register failed (%d)\n", ret);
117 goto framer_power_off;
118 }
119
120 return 0;
121
122 framer_power_off:
123 framer_power_off(qmc_hdlc->framer);
124 return ret;
125 }
126
qmc_hdlc_framer_stop(struct qmc_hdlc * qmc_hdlc)127 static void qmc_hdlc_framer_stop(struct qmc_hdlc *qmc_hdlc)
128 {
129 if (!qmc_hdlc->framer)
130 return;
131
132 framer_notifier_unregister(qmc_hdlc->framer, &qmc_hdlc->nb);
133 framer_power_off(qmc_hdlc->framer);
134 }
135
qmc_hdlc_framer_set_iface(struct qmc_hdlc * qmc_hdlc,int if_iface,const te1_settings * te1)136 static int qmc_hdlc_framer_set_iface(struct qmc_hdlc *qmc_hdlc, int if_iface,
137 const te1_settings *te1)
138 {
139 struct framer_config config;
140 int ret;
141
142 if (!qmc_hdlc->framer)
143 return 0;
144
145 ret = framer_get_config(qmc_hdlc->framer, &config);
146 if (ret)
147 return ret;
148
149 switch (if_iface) {
150 case IF_IFACE_E1:
151 config.iface = FRAMER_IFACE_E1;
152 break;
153 case IF_IFACE_T1:
154 config.iface = FRAMER_IFACE_T1;
155 break;
156 default:
157 return -EINVAL;
158 }
159
160 switch (te1->clock_type) {
161 case CLOCK_DEFAULT:
162 /* Keep current value */
163 break;
164 case CLOCK_EXT:
165 config.clock_type = FRAMER_CLOCK_EXT;
166 break;
167 case CLOCK_INT:
168 config.clock_type = FRAMER_CLOCK_INT;
169 break;
170 default:
171 return -EINVAL;
172 }
173 config.line_clock_rate = te1->clock_rate;
174
175 return framer_set_config(qmc_hdlc->framer, &config);
176 }
177
qmc_hdlc_framer_get_iface(struct qmc_hdlc * qmc_hdlc,int * if_iface,te1_settings * te1)178 static int qmc_hdlc_framer_get_iface(struct qmc_hdlc *qmc_hdlc, int *if_iface, te1_settings *te1)
179 {
180 struct framer_config config;
181 int ret;
182
183 if (!qmc_hdlc->framer) {
184 *if_iface = IF_IFACE_E1;
185 return 0;
186 }
187
188 ret = framer_get_config(qmc_hdlc->framer, &config);
189 if (ret)
190 return ret;
191
192 switch (config.iface) {
193 case FRAMER_IFACE_E1:
194 *if_iface = IF_IFACE_E1;
195 break;
196 case FRAMER_IFACE_T1:
197 *if_iface = IF_IFACE_T1;
198 break;
199 }
200
201 if (!te1)
202 return 0; /* Only iface type requested */
203
204 switch (config.clock_type) {
205 case FRAMER_CLOCK_EXT:
206 te1->clock_type = CLOCK_EXT;
207 break;
208 case FRAMER_CLOCK_INT:
209 te1->clock_type = CLOCK_INT;
210 break;
211 default:
212 return -EINVAL;
213 }
214 te1->clock_rate = config.line_clock_rate;
215 return 0;
216 }
217
qmc_hdlc_framer_init(struct qmc_hdlc * qmc_hdlc)218 static int qmc_hdlc_framer_init(struct qmc_hdlc *qmc_hdlc)
219 {
220 int ret;
221
222 if (!qmc_hdlc->framer)
223 return 0;
224
225 ret = framer_init(qmc_hdlc->framer);
226 if (ret) {
227 dev_err(qmc_hdlc->dev, "framer init failed (%d)\n", ret);
228 return ret;
229 }
230
231 return 0;
232 }
233
qmc_hdlc_framer_exit(struct qmc_hdlc * qmc_hdlc)234 static void qmc_hdlc_framer_exit(struct qmc_hdlc *qmc_hdlc)
235 {
236 if (!qmc_hdlc->framer)
237 return;
238
239 framer_exit(qmc_hdlc->framer);
240 }
241
242 static int qmc_hdlc_recv_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc, size_t size);
243
244 #define QMC_HDLC_RX_ERROR_FLAGS \
245 (QMC_RX_FLAG_HDLC_OVF | QMC_RX_FLAG_HDLC_UNA | \
246 QMC_RX_FLAG_HDLC_CRC | QMC_RX_FLAG_HDLC_ABORT)
247
qmc_hcld_recv_complete(void * context,size_t length,unsigned int flags)248 static void qmc_hcld_recv_complete(void *context, size_t length, unsigned int flags)
249 {
250 struct qmc_hdlc_desc *desc = context;
251 struct net_device *netdev;
252 struct qmc_hdlc *qmc_hdlc;
253 size_t crc_size;
254 int ret;
255
256 netdev = desc->netdev;
257 qmc_hdlc = netdev_to_qmc_hdlc(netdev);
258
259 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_FROM_DEVICE);
260
261 if (flags & QMC_HDLC_RX_ERROR_FLAGS) {
262 netdev->stats.rx_errors++;
263 if (flags & QMC_RX_FLAG_HDLC_OVF) /* Data overflow */
264 netdev->stats.rx_over_errors++;
265 if (flags & QMC_RX_FLAG_HDLC_UNA) /* bits received not multiple of 8 */
266 netdev->stats.rx_frame_errors++;
267 if (flags & QMC_RX_FLAG_HDLC_ABORT) /* Received an abort sequence */
268 netdev->stats.rx_frame_errors++;
269 if (flags & QMC_RX_FLAG_HDLC_CRC) /* CRC error */
270 netdev->stats.rx_crc_errors++;
271 kfree_skb(desc->skb);
272 goto re_queue;
273 }
274
275 /* Discard the CRC */
276 crc_size = qmc_hdlc->is_crc32 ? 4 : 2;
277 if (length < crc_size) {
278 netdev->stats.rx_length_errors++;
279 kfree_skb(desc->skb);
280 goto re_queue;
281 }
282 length -= crc_size;
283
284 netdev->stats.rx_packets++;
285 netdev->stats.rx_bytes += length;
286
287 skb_put(desc->skb, length);
288 desc->skb->protocol = hdlc_type_trans(desc->skb, netdev);
289 netif_rx(desc->skb);
290
291 re_queue:
292 /* Re-queue a transfer using the same descriptor */
293 ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, desc->dma_size);
294 if (ret) {
295 dev_err(qmc_hdlc->dev, "queue recv desc failed (%d)\n", ret);
296 netdev->stats.rx_errors++;
297 }
298 }
299
qmc_hdlc_recv_queue(struct qmc_hdlc * qmc_hdlc,struct qmc_hdlc_desc * desc,size_t size)300 static int qmc_hdlc_recv_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc, size_t size)
301 {
302 int ret;
303
304 desc->skb = dev_alloc_skb(size);
305 if (!desc->skb)
306 return -ENOMEM;
307
308 desc->dma_size = size;
309 desc->dma_addr = dma_map_single(qmc_hdlc->dev, desc->skb->data,
310 desc->dma_size, DMA_FROM_DEVICE);
311 ret = dma_mapping_error(qmc_hdlc->dev, desc->dma_addr);
312 if (ret)
313 goto free_skb;
314
315 ret = qmc_chan_read_submit(qmc_hdlc->qmc_chan, desc->dma_addr, desc->dma_size,
316 qmc_hcld_recv_complete, desc);
317 if (ret)
318 goto dma_unmap;
319
320 return 0;
321
322 dma_unmap:
323 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_FROM_DEVICE);
324 free_skb:
325 kfree_skb(desc->skb);
326 desc->skb = NULL;
327 return ret;
328 }
329
qmc_hdlc_xmit_complete(void * context)330 static void qmc_hdlc_xmit_complete(void *context)
331 {
332 struct qmc_hdlc_desc *desc = context;
333 struct net_device *netdev;
334 struct qmc_hdlc *qmc_hdlc;
335 struct sk_buff *skb;
336
337 netdev = desc->netdev;
338 qmc_hdlc = netdev_to_qmc_hdlc(netdev);
339
340 scoped_guard(spinlock_irqsave, &qmc_hdlc->tx_lock) {
341 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_TO_DEVICE);
342 skb = desc->skb;
343 desc->skb = NULL; /* Release the descriptor */
344 if (netif_queue_stopped(netdev))
345 netif_wake_queue(netdev);
346 }
347
348 netdev->stats.tx_packets++;
349 netdev->stats.tx_bytes += skb->len;
350
351 dev_consume_skb_any(skb);
352 }
353
qmc_hdlc_xmit_queue(struct qmc_hdlc * qmc_hdlc,struct qmc_hdlc_desc * desc)354 static int qmc_hdlc_xmit_queue(struct qmc_hdlc *qmc_hdlc, struct qmc_hdlc_desc *desc)
355 {
356 int ret;
357
358 desc->dma_addr = dma_map_single(qmc_hdlc->dev, desc->skb->data,
359 desc->dma_size, DMA_TO_DEVICE);
360 ret = dma_mapping_error(qmc_hdlc->dev, desc->dma_addr);
361 if (ret) {
362 dev_err(qmc_hdlc->dev, "failed to map skb\n");
363 return ret;
364 }
365
366 ret = qmc_chan_write_submit(qmc_hdlc->qmc_chan, desc->dma_addr, desc->dma_size,
367 qmc_hdlc_xmit_complete, desc);
368 if (ret) {
369 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size, DMA_TO_DEVICE);
370 dev_err(qmc_hdlc->dev, "qmc chan write returns %d\n", ret);
371 return ret;
372 }
373
374 return 0;
375 }
376
qmc_hdlc_xmit(struct sk_buff * skb,struct net_device * netdev)377 static netdev_tx_t qmc_hdlc_xmit(struct sk_buff *skb, struct net_device *netdev)
378 {
379 struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
380 struct qmc_hdlc_desc *desc;
381 int err;
382
383 guard(spinlock_irqsave)(&qmc_hdlc->tx_lock);
384
385 desc = &qmc_hdlc->tx_descs[qmc_hdlc->tx_out];
386 if (WARN_ONCE(desc->skb, "No tx descriptors available\n")) {
387 /* Should never happen.
388 * Previous xmit should have already stopped the queue.
389 */
390 netif_stop_queue(netdev);
391 return NETDEV_TX_BUSY;
392 }
393
394 desc->netdev = netdev;
395 desc->dma_size = skb->len;
396 desc->skb = skb;
397 err = qmc_hdlc_xmit_queue(qmc_hdlc, desc);
398 if (err) {
399 desc->skb = NULL; /* Release the descriptor */
400 if (err == -EBUSY) {
401 netif_stop_queue(netdev);
402 return NETDEV_TX_BUSY;
403 }
404 dev_kfree_skb(skb);
405 netdev->stats.tx_dropped++;
406 return NETDEV_TX_OK;
407 }
408
409 qmc_hdlc->tx_out = (qmc_hdlc->tx_out + 1) % ARRAY_SIZE(qmc_hdlc->tx_descs);
410
411 if (qmc_hdlc->tx_descs[qmc_hdlc->tx_out].skb)
412 netif_stop_queue(netdev);
413
414 return NETDEV_TX_OK;
415 }
416
qmc_hdlc_xlate_slot_map(struct qmc_hdlc * qmc_hdlc,u32 slot_map,struct qmc_chan_ts_info * ts_info)417 static int qmc_hdlc_xlate_slot_map(struct qmc_hdlc *qmc_hdlc,
418 u32 slot_map, struct qmc_chan_ts_info *ts_info)
419 {
420 DECLARE_BITMAP(ts_mask_avail, 64);
421 DECLARE_BITMAP(ts_mask, 64);
422 DECLARE_BITMAP(map, 64);
423
424 /* Tx and Rx available masks must be identical */
425 if (ts_info->rx_ts_mask_avail != ts_info->tx_ts_mask_avail) {
426 dev_err(qmc_hdlc->dev, "tx and rx available timeslots mismatch (0x%llx, 0x%llx)\n",
427 ts_info->rx_ts_mask_avail, ts_info->tx_ts_mask_avail);
428 return -EINVAL;
429 }
430
431 bitmap_from_u64(ts_mask_avail, ts_info->rx_ts_mask_avail);
432 bitmap_from_u64(map, slot_map);
433 bitmap_scatter(ts_mask, map, ts_mask_avail, 64);
434
435 if (bitmap_weight(ts_mask, 64) != bitmap_weight(map, 64)) {
436 dev_err(qmc_hdlc->dev, "Cannot translate timeslots %64pb -> (%64pb, %64pb)\n",
437 map, ts_mask_avail, ts_mask);
438 return -EINVAL;
439 }
440
441 bitmap_to_arr64(&ts_info->tx_ts_mask, ts_mask, 64);
442 ts_info->rx_ts_mask = ts_info->tx_ts_mask;
443 return 0;
444 }
445
qmc_hdlc_xlate_ts_info(struct qmc_hdlc * qmc_hdlc,const struct qmc_chan_ts_info * ts_info,u32 * slot_map)446 static int qmc_hdlc_xlate_ts_info(struct qmc_hdlc *qmc_hdlc,
447 const struct qmc_chan_ts_info *ts_info, u32 *slot_map)
448 {
449 DECLARE_BITMAP(ts_mask_avail, 64);
450 DECLARE_BITMAP(ts_mask, 64);
451 DECLARE_BITMAP(map, 64);
452 u32 slot_array[2];
453
454 /* Tx and Rx masks and available masks must be identical */
455 if (ts_info->rx_ts_mask_avail != ts_info->tx_ts_mask_avail) {
456 dev_err(qmc_hdlc->dev, "tx and rx available timeslots mismatch (0x%llx, 0x%llx)\n",
457 ts_info->rx_ts_mask_avail, ts_info->tx_ts_mask_avail);
458 return -EINVAL;
459 }
460 if (ts_info->rx_ts_mask != ts_info->tx_ts_mask) {
461 dev_err(qmc_hdlc->dev, "tx and rx timeslots mismatch (0x%llx, 0x%llx)\n",
462 ts_info->rx_ts_mask, ts_info->tx_ts_mask);
463 return -EINVAL;
464 }
465
466 bitmap_from_u64(ts_mask_avail, ts_info->rx_ts_mask_avail);
467 bitmap_from_u64(ts_mask, ts_info->rx_ts_mask);
468 bitmap_gather(map, ts_mask, ts_mask_avail, 64);
469
470 if (bitmap_weight(ts_mask, 64) != bitmap_weight(map, 64)) {
471 dev_err(qmc_hdlc->dev, "Cannot translate timeslots (%64pb, %64pb) -> %64pb\n",
472 ts_mask_avail, ts_mask, map);
473 return -EINVAL;
474 }
475
476 bitmap_to_arr32(slot_array, map, 64);
477 if (slot_array[1]) {
478 dev_err(qmc_hdlc->dev, "Slot map out of 32bit (%64pb, %64pb) -> %64pb\n",
479 ts_mask_avail, ts_mask, map);
480 return -EINVAL;
481 }
482
483 *slot_map = slot_array[0];
484 return 0;
485 }
486
qmc_hdlc_set_iface(struct qmc_hdlc * qmc_hdlc,int if_iface,const te1_settings * te1)487 static int qmc_hdlc_set_iface(struct qmc_hdlc *qmc_hdlc, int if_iface, const te1_settings *te1)
488 {
489 struct qmc_chan_ts_info ts_info;
490 int ret;
491
492 ret = qmc_chan_get_ts_info(qmc_hdlc->qmc_chan, &ts_info);
493 if (ret) {
494 dev_err(qmc_hdlc->dev, "get QMC channel ts info failed %d\n", ret);
495 return ret;
496 }
497 ret = qmc_hdlc_xlate_slot_map(qmc_hdlc, te1->slot_map, &ts_info);
498 if (ret)
499 return ret;
500
501 ret = qmc_chan_set_ts_info(qmc_hdlc->qmc_chan, &ts_info);
502 if (ret) {
503 dev_err(qmc_hdlc->dev, "set QMC channel ts info failed %d\n", ret);
504 return ret;
505 }
506
507 qmc_hdlc->slot_map = te1->slot_map;
508
509 ret = qmc_hdlc_framer_set_iface(qmc_hdlc, if_iface, te1);
510 if (ret) {
511 dev_err(qmc_hdlc->dev, "framer set iface failed %d\n", ret);
512 return ret;
513 }
514
515 return 0;
516 }
517
qmc_hdlc_ioctl(struct net_device * netdev,struct if_settings * ifs)518 static int qmc_hdlc_ioctl(struct net_device *netdev, struct if_settings *ifs)
519 {
520 struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
521 te1_settings te1;
522 int ret;
523
524 switch (ifs->type) {
525 case IF_GET_IFACE:
526 if (ifs->size < sizeof(te1)) {
527 /* Retrieve type only */
528 ret = qmc_hdlc_framer_get_iface(qmc_hdlc, &ifs->type, NULL);
529 if (ret)
530 return ret;
531
532 if (!ifs->size)
533 return 0; /* only type requested */
534
535 ifs->size = sizeof(te1); /* data size wanted */
536 return -ENOBUFS;
537 }
538
539 memset(&te1, 0, sizeof(te1));
540
541 /* Retrieve info from framer */
542 ret = qmc_hdlc_framer_get_iface(qmc_hdlc, &ifs->type, &te1);
543 if (ret)
544 return ret;
545
546 /* Update slot_map */
547 te1.slot_map = qmc_hdlc->slot_map;
548
549 if (copy_to_user(ifs->ifs_ifsu.te1, &te1, sizeof(te1)))
550 return -EFAULT;
551 return 0;
552
553 case IF_IFACE_E1:
554 case IF_IFACE_T1:
555 if (!capable(CAP_NET_ADMIN))
556 return -EPERM;
557
558 if (netdev->flags & IFF_UP)
559 return -EBUSY;
560
561 if (copy_from_user(&te1, ifs->ifs_ifsu.te1, sizeof(te1)))
562 return -EFAULT;
563
564 return qmc_hdlc_set_iface(qmc_hdlc, ifs->type, &te1);
565
566 default:
567 return hdlc_ioctl(netdev, ifs);
568 }
569 }
570
qmc_hdlc_open(struct net_device * netdev)571 static int qmc_hdlc_open(struct net_device *netdev)
572 {
573 struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
574 struct qmc_chan_param chan_param;
575 struct qmc_hdlc_desc *desc;
576 int ret;
577 int i;
578
579 ret = qmc_hdlc_framer_start(qmc_hdlc);
580 if (ret)
581 return ret;
582
583 ret = hdlc_open(netdev);
584 if (ret)
585 goto framer_stop;
586
587 /* Update carrier */
588 qmc_hdlc_framer_set_carrier(qmc_hdlc);
589
590 chan_param.mode = QMC_HDLC;
591 /* HDLC_MAX_MRU + 4 for the CRC
592 * HDLC_MAX_MRU + 4 + 8 for the CRC and some extraspace needed by the QMC
593 */
594 chan_param.hdlc.max_rx_buf_size = HDLC_MAX_MRU + 4 + 8;
595 chan_param.hdlc.max_rx_frame_size = HDLC_MAX_MRU + 4;
596 chan_param.hdlc.is_crc32 = qmc_hdlc->is_crc32;
597 ret = qmc_chan_set_param(qmc_hdlc->qmc_chan, &chan_param);
598 if (ret) {
599 dev_err(qmc_hdlc->dev, "failed to set param (%d)\n", ret);
600 goto hdlc_close;
601 }
602
603 /* Queue as many recv descriptors as possible */
604 for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
605 desc = &qmc_hdlc->rx_descs[i];
606
607 desc->netdev = netdev;
608 ret = qmc_hdlc_recv_queue(qmc_hdlc, desc, chan_param.hdlc.max_rx_buf_size);
609 if (ret == -EBUSY && i != 0)
610 break; /* We use all the QMC chan capability */
611 if (ret)
612 goto free_desc;
613 }
614
615 ret = qmc_chan_start(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
616 if (ret) {
617 dev_err(qmc_hdlc->dev, "qmc chan start failed (%d)\n", ret);
618 goto free_desc;
619 }
620
621 netif_start_queue(netdev);
622
623 return 0;
624
625 free_desc:
626 qmc_chan_reset(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
627 while (i--) {
628 desc = &qmc_hdlc->rx_descs[i];
629 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size,
630 DMA_FROM_DEVICE);
631 kfree_skb(desc->skb);
632 desc->skb = NULL;
633 }
634 hdlc_close:
635 hdlc_close(netdev);
636 framer_stop:
637 qmc_hdlc_framer_stop(qmc_hdlc);
638 return ret;
639 }
640
qmc_hdlc_close(struct net_device * netdev)641 static int qmc_hdlc_close(struct net_device *netdev)
642 {
643 struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
644 struct qmc_hdlc_desc *desc;
645 int i;
646
647 qmc_chan_stop(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
648 qmc_chan_reset(qmc_hdlc->qmc_chan, QMC_CHAN_ALL);
649
650 netif_stop_queue(netdev);
651
652 for (i = 0; i < ARRAY_SIZE(qmc_hdlc->tx_descs); i++) {
653 desc = &qmc_hdlc->tx_descs[i];
654 if (!desc->skb)
655 continue;
656 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size,
657 DMA_TO_DEVICE);
658 kfree_skb(desc->skb);
659 desc->skb = NULL;
660 }
661
662 for (i = 0; i < ARRAY_SIZE(qmc_hdlc->rx_descs); i++) {
663 desc = &qmc_hdlc->rx_descs[i];
664 if (!desc->skb)
665 continue;
666 dma_unmap_single(qmc_hdlc->dev, desc->dma_addr, desc->dma_size,
667 DMA_FROM_DEVICE);
668 kfree_skb(desc->skb);
669 desc->skb = NULL;
670 }
671
672 hdlc_close(netdev);
673 qmc_hdlc_framer_stop(qmc_hdlc);
674 return 0;
675 }
676
qmc_hdlc_attach(struct net_device * netdev,unsigned short encoding,unsigned short parity)677 static int qmc_hdlc_attach(struct net_device *netdev, unsigned short encoding,
678 unsigned short parity)
679 {
680 struct qmc_hdlc *qmc_hdlc = netdev_to_qmc_hdlc(netdev);
681
682 if (encoding != ENCODING_NRZ)
683 return -EINVAL;
684
685 switch (parity) {
686 case PARITY_CRC16_PR1_CCITT:
687 qmc_hdlc->is_crc32 = false;
688 break;
689 case PARITY_CRC32_PR1_CCITT:
690 qmc_hdlc->is_crc32 = true;
691 break;
692 default:
693 dev_err(qmc_hdlc->dev, "unsupported parity %u\n", parity);
694 return -EINVAL;
695 }
696
697 return 0;
698 }
699
700 static const struct net_device_ops qmc_hdlc_netdev_ops = {
701 .ndo_open = qmc_hdlc_open,
702 .ndo_stop = qmc_hdlc_close,
703 .ndo_start_xmit = hdlc_start_xmit,
704 .ndo_siocwandev = qmc_hdlc_ioctl,
705 };
706
qmc_hdlc_probe(struct platform_device * pdev)707 static int qmc_hdlc_probe(struct platform_device *pdev)
708 {
709 struct device *dev = &pdev->dev;
710 struct qmc_chan_ts_info ts_info;
711 struct qmc_hdlc *qmc_hdlc;
712 struct qmc_chan_info info;
713 hdlc_device *hdlc;
714 int ret;
715
716 qmc_hdlc = devm_kzalloc(dev, sizeof(*qmc_hdlc), GFP_KERNEL);
717 if (!qmc_hdlc)
718 return -ENOMEM;
719
720 qmc_hdlc->dev = dev;
721 spin_lock_init(&qmc_hdlc->tx_lock);
722 mutex_init(&qmc_hdlc->carrier_lock);
723
724 qmc_hdlc->qmc_chan = devm_qmc_chan_get_bychild(dev, dev->of_node);
725 if (IS_ERR(qmc_hdlc->qmc_chan))
726 return dev_err_probe(dev, PTR_ERR(qmc_hdlc->qmc_chan),
727 "get QMC channel failed\n");
728
729 ret = qmc_chan_get_info(qmc_hdlc->qmc_chan, &info);
730 if (ret)
731 return dev_err_probe(dev, ret, "get QMC channel info failed\n");
732
733 if (info.mode != QMC_HDLC)
734 return dev_err_probe(dev, -EINVAL, "QMC chan mode %d is not QMC_HDLC\n",
735 info.mode);
736
737 ret = qmc_chan_get_ts_info(qmc_hdlc->qmc_chan, &ts_info);
738 if (ret)
739 return dev_err_probe(dev, ret, "get QMC channel ts info failed\n");
740
741 ret = qmc_hdlc_xlate_ts_info(qmc_hdlc, &ts_info, &qmc_hdlc->slot_map);
742 if (ret)
743 return ret;
744
745 qmc_hdlc->framer = devm_framer_optional_get(dev, "fsl,framer");
746 if (IS_ERR(qmc_hdlc->framer))
747 return PTR_ERR(qmc_hdlc->framer);
748
749 ret = qmc_hdlc_framer_init(qmc_hdlc);
750 if (ret)
751 return ret;
752
753 qmc_hdlc->netdev = alloc_hdlcdev(qmc_hdlc);
754 if (!qmc_hdlc->netdev) {
755 ret = -ENOMEM;
756 goto framer_exit;
757 }
758
759 hdlc = dev_to_hdlc(qmc_hdlc->netdev);
760 hdlc->attach = qmc_hdlc_attach;
761 hdlc->xmit = qmc_hdlc_xmit;
762 SET_NETDEV_DEV(qmc_hdlc->netdev, dev);
763 qmc_hdlc->netdev->tx_queue_len = ARRAY_SIZE(qmc_hdlc->tx_descs);
764 qmc_hdlc->netdev->netdev_ops = &qmc_hdlc_netdev_ops;
765 ret = register_hdlc_device(qmc_hdlc->netdev);
766 if (ret) {
767 dev_err_probe(dev, ret, "failed to register hdlc device\n");
768 goto free_netdev;
769 }
770
771 platform_set_drvdata(pdev, qmc_hdlc);
772 return 0;
773
774 free_netdev:
775 free_netdev(qmc_hdlc->netdev);
776 framer_exit:
777 qmc_hdlc_framer_exit(qmc_hdlc);
778 return ret;
779 }
780
qmc_hdlc_remove(struct platform_device * pdev)781 static void qmc_hdlc_remove(struct platform_device *pdev)
782 {
783 struct qmc_hdlc *qmc_hdlc = platform_get_drvdata(pdev);
784
785 unregister_hdlc_device(qmc_hdlc->netdev);
786 free_netdev(qmc_hdlc->netdev);
787 qmc_hdlc_framer_exit(qmc_hdlc);
788 }
789
790 static const struct of_device_id qmc_hdlc_id_table[] = {
791 { .compatible = "fsl,qmc-hdlc" },
792 {} /* sentinel */
793 };
794 MODULE_DEVICE_TABLE(of, qmc_hdlc_id_table);
795
796 static struct platform_driver qmc_hdlc_driver = {
797 .driver = {
798 .name = "fsl-qmc-hdlc",
799 .of_match_table = qmc_hdlc_id_table,
800 },
801 .probe = qmc_hdlc_probe,
802 .remove_new = qmc_hdlc_remove,
803 };
804 module_platform_driver(qmc_hdlc_driver);
805
806 MODULE_AUTHOR("Herve Codina <herve.codina@bootlin.com>");
807 MODULE_DESCRIPTION("QMC HDLC driver");
808 MODULE_LICENSE("GPL");
809