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8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9#include <linux/module.h>
10#include <linux/fs.h>
11#include <linux/slab.h>
12#include <linux/init.h>
13#include <linux/device.h>
14#include <linux/list.h>
15#include <linux/poll.h>
16#include <linux/wait.h>
17#include <linux/kobject.h>
18#include <linux/mutex.h>
19#include <linux/completion.h>
20#include <linux/sysfs.h>
21#include <linux/kthread.h>
22#include <linux/dma-mapping.h>
23#include <linux/idr.h>
24#include <most/core.h>
25
26#define MAX_CHANNELS 64
27#define STRING_SIZE 80
28
29static struct ida mdev_id;
30static int dummy_num_buffers;
31
32static struct mostcore {
33 struct device dev;
34 struct device_driver drv;
35 struct bus_type bus;
36 struct list_head comp_list;
37} mc;
38
39#define to_driver(d) container_of(d, struct mostcore, drv)
40
41struct pipe {
42 struct core_component *comp;
43 int refs;
44 int num_buffers;
45};
46
47struct most_channel {
48 struct device dev;
49 struct completion cleanup;
50 atomic_t mbo_ref;
51 atomic_t mbo_nq_level;
52 u16 channel_id;
53 char name[STRING_SIZE];
54 bool is_poisoned;
55 struct mutex start_mutex;
56 struct mutex nq_mutex;
57 int is_starving;
58 struct most_interface *iface;
59 struct most_channel_config cfg;
60 bool keep_mbo;
61 bool enqueue_halt;
62 struct list_head fifo;
63 spinlock_t fifo_lock;
64 struct list_head halt_fifo;
65 struct list_head list;
66 struct pipe pipe0;
67 struct pipe pipe1;
68 struct list_head trash_fifo;
69 struct task_struct *hdm_enqueue_task;
70 wait_queue_head_t hdm_fifo_wq;
71
72};
73
74#define to_channel(d) container_of(d, struct most_channel, dev)
75
76struct interface_private {
77 int dev_id;
78 char name[STRING_SIZE];
79 struct most_channel *channel[MAX_CHANNELS];
80 struct list_head channel_list;
81};
82
83static const struct {
84 int most_ch_data_type;
85 const char *name;
86} ch_data_type[] = {
87 { MOST_CH_CONTROL, "control\n" },
88 { MOST_CH_ASYNC, "async\n" },
89 { MOST_CH_SYNC, "sync\n" },
90 { MOST_CH_ISOC, "isoc\n"},
91 { MOST_CH_ISOC, "isoc_avp\n"},
92};
93
94
95
96
97
98#define list_pop_mbo(ptr) \
99({ \
100 struct mbo *_mbo = list_first_entry(ptr, struct mbo, list); \
101 list_del(&_mbo->list); \
102 _mbo; \
103})
104
105
106
107
108
109static void most_free_mbo_coherent(struct mbo *mbo)
110{
111 struct most_channel *c = mbo->context;
112 u16 const coherent_buf_size = c->cfg.buffer_size + c->cfg.extra_len;
113
114 if (c->iface->dma_free)
115 c->iface->dma_free(mbo, coherent_buf_size);
116 else
117 kfree(mbo->virt_address);
118 kfree(mbo);
119 if (atomic_sub_and_test(1, &c->mbo_ref))
120 complete(&c->cleanup);
121}
122
123
124
125
126
127static void flush_channel_fifos(struct most_channel *c)
128{
129 unsigned long flags, hf_flags;
130 struct mbo *mbo, *tmp;
131
132 if (list_empty(&c->fifo) && list_empty(&c->halt_fifo))
133 return;
134
135 spin_lock_irqsave(&c->fifo_lock, flags);
136 list_for_each_entry_safe(mbo, tmp, &c->fifo, list) {
137 list_del(&mbo->list);
138 spin_unlock_irqrestore(&c->fifo_lock, flags);
139 most_free_mbo_coherent(mbo);
140 spin_lock_irqsave(&c->fifo_lock, flags);
141 }
142 spin_unlock_irqrestore(&c->fifo_lock, flags);
143
144 spin_lock_irqsave(&c->fifo_lock, hf_flags);
145 list_for_each_entry_safe(mbo, tmp, &c->halt_fifo, list) {
146 list_del(&mbo->list);
147 spin_unlock_irqrestore(&c->fifo_lock, hf_flags);
148 most_free_mbo_coherent(mbo);
149 spin_lock_irqsave(&c->fifo_lock, hf_flags);
150 }
151 spin_unlock_irqrestore(&c->fifo_lock, hf_flags);
152
153 if (unlikely((!list_empty(&c->fifo) || !list_empty(&c->halt_fifo))))
154 pr_info("WARN: fifo | trash fifo not empty\n");
155}
156
157
158
159
160
161static int flush_trash_fifo(struct most_channel *c)
162{
163 struct mbo *mbo, *tmp;
164 unsigned long flags;
165
166 spin_lock_irqsave(&c->fifo_lock, flags);
167 list_for_each_entry_safe(mbo, tmp, &c->trash_fifo, list) {
168 list_del(&mbo->list);
169 spin_unlock_irqrestore(&c->fifo_lock, flags);
170 most_free_mbo_coherent(mbo);
171 spin_lock_irqsave(&c->fifo_lock, flags);
172 }
173 spin_unlock_irqrestore(&c->fifo_lock, flags);
174 return 0;
175}
176
177static ssize_t available_directions_show(struct device *dev,
178 struct device_attribute *attr,
179 char *buf)
180{
181 struct most_channel *c = to_channel(dev);
182 unsigned int i = c->channel_id;
183
184 strcpy(buf, "");
185 if (c->iface->channel_vector[i].direction & MOST_CH_RX)
186 strcat(buf, "rx ");
187 if (c->iface->channel_vector[i].direction & MOST_CH_TX)
188 strcat(buf, "tx ");
189 strcat(buf, "\n");
190 return strlen(buf);
191}
192
193static ssize_t available_datatypes_show(struct device *dev,
194 struct device_attribute *attr,
195 char *buf)
196{
197 struct most_channel *c = to_channel(dev);
198 unsigned int i = c->channel_id;
199
200 strcpy(buf, "");
201 if (c->iface->channel_vector[i].data_type & MOST_CH_CONTROL)
202 strcat(buf, "control ");
203 if (c->iface->channel_vector[i].data_type & MOST_CH_ASYNC)
204 strcat(buf, "async ");
205 if (c->iface->channel_vector[i].data_type & MOST_CH_SYNC)
206 strcat(buf, "sync ");
207 if (c->iface->channel_vector[i].data_type & MOST_CH_ISOC)
208 strcat(buf, "isoc ");
209 strcat(buf, "\n");
210 return strlen(buf);
211}
212
213static ssize_t number_of_packet_buffers_show(struct device *dev,
214 struct device_attribute *attr,
215 char *buf)
216{
217 struct most_channel *c = to_channel(dev);
218 unsigned int i = c->channel_id;
219
220 return snprintf(buf, PAGE_SIZE, "%d\n",
221 c->iface->channel_vector[i].num_buffers_packet);
222}
223
224static ssize_t number_of_stream_buffers_show(struct device *dev,
225 struct device_attribute *attr,
226 char *buf)
227{
228 struct most_channel *c = to_channel(dev);
229 unsigned int i = c->channel_id;
230
231 return snprintf(buf, PAGE_SIZE, "%d\n",
232 c->iface->channel_vector[i].num_buffers_streaming);
233}
234
235static ssize_t size_of_packet_buffer_show(struct device *dev,
236 struct device_attribute *attr,
237 char *buf)
238{
239 struct most_channel *c = to_channel(dev);
240 unsigned int i = c->channel_id;
241
242 return snprintf(buf, PAGE_SIZE, "%d\n",
243 c->iface->channel_vector[i].buffer_size_packet);
244}
245
246static ssize_t size_of_stream_buffer_show(struct device *dev,
247 struct device_attribute *attr,
248 char *buf)
249{
250 struct most_channel *c = to_channel(dev);
251 unsigned int i = c->channel_id;
252
253 return snprintf(buf, PAGE_SIZE, "%d\n",
254 c->iface->channel_vector[i].buffer_size_streaming);
255}
256
257static ssize_t channel_starving_show(struct device *dev,
258 struct device_attribute *attr,
259 char *buf)
260{
261 struct most_channel *c = to_channel(dev);
262
263 return snprintf(buf, PAGE_SIZE, "%d\n", c->is_starving);
264}
265
266static ssize_t set_number_of_buffers_show(struct device *dev,
267 struct device_attribute *attr,
268 char *buf)
269{
270 struct most_channel *c = to_channel(dev);
271
272 return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.num_buffers);
273}
274
275static ssize_t set_buffer_size_show(struct device *dev,
276 struct device_attribute *attr,
277 char *buf)
278{
279 struct most_channel *c = to_channel(dev);
280
281 return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.buffer_size);
282}
283
284static ssize_t set_direction_show(struct device *dev,
285 struct device_attribute *attr,
286 char *buf)
287{
288 struct most_channel *c = to_channel(dev);
289
290 if (c->cfg.direction & MOST_CH_TX)
291 return snprintf(buf, PAGE_SIZE, "tx\n");
292 else if (c->cfg.direction & MOST_CH_RX)
293 return snprintf(buf, PAGE_SIZE, "rx\n");
294 return snprintf(buf, PAGE_SIZE, "unconfigured\n");
295}
296
297static ssize_t set_datatype_show(struct device *dev,
298 struct device_attribute *attr,
299 char *buf)
300{
301 int i;
302 struct most_channel *c = to_channel(dev);
303
304 for (i = 0; i < ARRAY_SIZE(ch_data_type); i++) {
305 if (c->cfg.data_type & ch_data_type[i].most_ch_data_type)
306 return snprintf(buf, PAGE_SIZE, "%s", ch_data_type[i].name);
307 }
308 return snprintf(buf, PAGE_SIZE, "unconfigured\n");
309}
310
311static ssize_t set_subbuffer_size_show(struct device *dev,
312 struct device_attribute *attr,
313 char *buf)
314{
315 struct most_channel *c = to_channel(dev);
316
317 return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.subbuffer_size);
318}
319
320static ssize_t set_packets_per_xact_show(struct device *dev,
321 struct device_attribute *attr,
322 char *buf)
323{
324 struct most_channel *c = to_channel(dev);
325
326 return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.packets_per_xact);
327}
328
329static ssize_t set_dbr_size_show(struct device *dev,
330 struct device_attribute *attr, char *buf)
331{
332 struct most_channel *c = to_channel(dev);
333
334 return snprintf(buf, PAGE_SIZE, "%d\n", c->cfg.dbr_size);
335}
336
337#define to_dev_attr(a) container_of(a, struct device_attribute, attr)
338static umode_t channel_attr_is_visible(struct kobject *kobj,
339 struct attribute *attr, int index)
340{
341 struct device_attribute *dev_attr = to_dev_attr(attr);
342 struct device *dev = kobj_to_dev(kobj);
343 struct most_channel *c = to_channel(dev);
344
345 if (!strcmp(dev_attr->attr.name, "set_dbr_size") &&
346 (c->iface->interface != ITYPE_MEDIALB_DIM2))
347 return 0;
348 if (!strcmp(dev_attr->attr.name, "set_packets_per_xact") &&
349 (c->iface->interface != ITYPE_USB))
350 return 0;
351
352 return attr->mode;
353}
354
355#define DEV_ATTR(_name) (&dev_attr_##_name.attr)
356
357static DEVICE_ATTR_RO(available_directions);
358static DEVICE_ATTR_RO(available_datatypes);
359static DEVICE_ATTR_RO(number_of_packet_buffers);
360static DEVICE_ATTR_RO(number_of_stream_buffers);
361static DEVICE_ATTR_RO(size_of_stream_buffer);
362static DEVICE_ATTR_RO(size_of_packet_buffer);
363static DEVICE_ATTR_RO(channel_starving);
364static DEVICE_ATTR_RO(set_buffer_size);
365static DEVICE_ATTR_RO(set_number_of_buffers);
366static DEVICE_ATTR_RO(set_direction);
367static DEVICE_ATTR_RO(set_datatype);
368static DEVICE_ATTR_RO(set_subbuffer_size);
369static DEVICE_ATTR_RO(set_packets_per_xact);
370static DEVICE_ATTR_RO(set_dbr_size);
371
372static struct attribute *channel_attrs[] = {
373 DEV_ATTR(available_directions),
374 DEV_ATTR(available_datatypes),
375 DEV_ATTR(number_of_packet_buffers),
376 DEV_ATTR(number_of_stream_buffers),
377 DEV_ATTR(size_of_stream_buffer),
378 DEV_ATTR(size_of_packet_buffer),
379 DEV_ATTR(channel_starving),
380 DEV_ATTR(set_buffer_size),
381 DEV_ATTR(set_number_of_buffers),
382 DEV_ATTR(set_direction),
383 DEV_ATTR(set_datatype),
384 DEV_ATTR(set_subbuffer_size),
385 DEV_ATTR(set_packets_per_xact),
386 DEV_ATTR(set_dbr_size),
387 NULL,
388};
389
390static struct attribute_group channel_attr_group = {
391 .attrs = channel_attrs,
392 .is_visible = channel_attr_is_visible,
393};
394
395static const struct attribute_group *channel_attr_groups[] = {
396 &channel_attr_group,
397 NULL,
398};
399
400static ssize_t description_show(struct device *dev,
401 struct device_attribute *attr,
402 char *buf)
403{
404 struct most_interface *iface = to_most_interface(dev);
405
406 return snprintf(buf, PAGE_SIZE, "%s\n", iface->description);
407}
408
409static ssize_t interface_show(struct device *dev,
410 struct device_attribute *attr,
411 char *buf)
412{
413 struct most_interface *iface = to_most_interface(dev);
414
415 switch (iface->interface) {
416 case ITYPE_LOOPBACK:
417 return snprintf(buf, PAGE_SIZE, "loopback\n");
418 case ITYPE_I2C:
419 return snprintf(buf, PAGE_SIZE, "i2c\n");
420 case ITYPE_I2S:
421 return snprintf(buf, PAGE_SIZE, "i2s\n");
422 case ITYPE_TSI:
423 return snprintf(buf, PAGE_SIZE, "tsi\n");
424 case ITYPE_HBI:
425 return snprintf(buf, PAGE_SIZE, "hbi\n");
426 case ITYPE_MEDIALB_DIM:
427 return snprintf(buf, PAGE_SIZE, "mlb_dim\n");
428 case ITYPE_MEDIALB_DIM2:
429 return snprintf(buf, PAGE_SIZE, "mlb_dim2\n");
430 case ITYPE_USB:
431 return snprintf(buf, PAGE_SIZE, "usb\n");
432 case ITYPE_PCIE:
433 return snprintf(buf, PAGE_SIZE, "pcie\n");
434 }
435 return snprintf(buf, PAGE_SIZE, "unknown\n");
436}
437
438static DEVICE_ATTR_RO(description);
439static DEVICE_ATTR_RO(interface);
440
441static struct attribute *interface_attrs[] = {
442 DEV_ATTR(description),
443 DEV_ATTR(interface),
444 NULL,
445};
446
447static struct attribute_group interface_attr_group = {
448 .attrs = interface_attrs,
449};
450
451static const struct attribute_group *interface_attr_groups[] = {
452 &interface_attr_group,
453 NULL,
454};
455
456static struct core_component *match_component(char *name)
457{
458 struct core_component *comp;
459
460 list_for_each_entry(comp, &mc.comp_list, list) {
461 if (!strcmp(comp->name, name))
462 return comp;
463 }
464 return NULL;
465}
466
467struct show_links_data {
468 int offs;
469 char *buf;
470};
471
472static int print_links(struct device *dev, void *data)
473{
474 struct show_links_data *d = data;
475 int offs = d->offs;
476 char *buf = d->buf;
477 struct most_channel *c;
478 struct most_interface *iface = to_most_interface(dev);
479
480 list_for_each_entry(c, &iface->p->channel_list, list) {
481 if (c->pipe0.comp) {
482 offs += snprintf(buf + offs,
483 PAGE_SIZE - offs,
484 "%s:%s:%s\n",
485 c->pipe0.comp->name,
486 dev_name(&iface->dev),
487 dev_name(&c->dev));
488 }
489 if (c->pipe1.comp) {
490 offs += snprintf(buf + offs,
491 PAGE_SIZE - offs,
492 "%s:%s:%s\n",
493 c->pipe1.comp->name,
494 dev_name(&iface->dev),
495 dev_name(&c->dev));
496 }
497 }
498 d->offs = offs;
499 return 0;
500}
501
502static ssize_t links_show(struct device_driver *drv, char *buf)
503{
504 struct show_links_data d = { .buf = buf };
505
506 bus_for_each_dev(&mc.bus, NULL, &d, print_links);
507 return d.offs;
508}
509
510static ssize_t components_show(struct device_driver *drv, char *buf)
511{
512 struct core_component *comp;
513 int offs = 0;
514
515 list_for_each_entry(comp, &mc.comp_list, list) {
516 offs += snprintf(buf + offs, PAGE_SIZE - offs, "%s\n",
517 comp->name);
518 }
519 return offs;
520}
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543
544static int split_string(char *buf, char **a, char **b, char **c, char **d)
545{
546 *a = strsep(&buf, ":");
547 if (!*a)
548 return -EIO;
549
550 *b = strsep(&buf, ":\n");
551 if (!*b)
552 return -EIO;
553
554 *c = strsep(&buf, ":\n");
555 if (!*c)
556 return -EIO;
557
558 if (d)
559 *d = strsep(&buf, ":\n");
560
561 return 0;
562}
563
564
565
566
567
568
569static struct most_channel *get_channel(char *mdev, char *mdev_ch)
570{
571 struct device *dev = NULL;
572 struct most_interface *iface;
573 struct most_channel *c, *tmp;
574
575 dev = bus_find_device_by_name(&mc.bus, NULL, mdev);
576 if (!dev)
577 return NULL;
578 iface = to_most_interface(dev);
579 list_for_each_entry_safe(c, tmp, &iface->p->channel_list, list) {
580 if (!strcmp(dev_name(&c->dev), mdev_ch))
581 return c;
582 }
583 return NULL;
584}
585
586static
587inline int link_channel_to_component(struct most_channel *c,
588 struct core_component *comp,
589 char *name,
590 char *comp_param)
591{
592 int ret;
593 struct core_component **comp_ptr;
594
595 if (!c->pipe0.comp)
596 comp_ptr = &c->pipe0.comp;
597 else if (!c->pipe1.comp)
598 comp_ptr = &c->pipe1.comp;
599 else
600 return -ENOSPC;
601
602 *comp_ptr = comp;
603 ret = comp->probe_channel(c->iface, c->channel_id, &c->cfg, name,
604 comp_param);
605 if (ret) {
606 *comp_ptr = NULL;
607 return ret;
608 }
609 return 0;
610}
611
612int most_set_cfg_buffer_size(char *mdev, char *mdev_ch, u16 val)
613{
614 struct most_channel *c = get_channel(mdev, mdev_ch);
615
616 if (!c)
617 return -ENODEV;
618 c->cfg.buffer_size = val;
619 return 0;
620}
621
622int most_set_cfg_subbuffer_size(char *mdev, char *mdev_ch, u16 val)
623{
624 struct most_channel *c = get_channel(mdev, mdev_ch);
625
626 if (!c)
627 return -ENODEV;
628 c->cfg.subbuffer_size = val;
629 return 0;
630}
631
632int most_set_cfg_dbr_size(char *mdev, char *mdev_ch, u16 val)
633{
634 struct most_channel *c = get_channel(mdev, mdev_ch);
635
636 if (!c)
637 return -ENODEV;
638 c->cfg.dbr_size = val;
639 return 0;
640}
641
642int most_set_cfg_num_buffers(char *mdev, char *mdev_ch, u16 val)
643{
644 struct most_channel *c = get_channel(mdev, mdev_ch);
645
646 if (!c)
647 return -ENODEV;
648 c->cfg.num_buffers = val;
649 return 0;
650}
651
652int most_set_cfg_datatype(char *mdev, char *mdev_ch, char *buf)
653{
654 int i;
655 struct most_channel *c = get_channel(mdev, mdev_ch);
656
657 if (!c)
658 return -ENODEV;
659 for (i = 0; i < ARRAY_SIZE(ch_data_type); i++) {
660 if (!strcmp(buf, ch_data_type[i].name)) {
661 c->cfg.data_type = ch_data_type[i].most_ch_data_type;
662 break;
663 }
664 }
665
666 if (i == ARRAY_SIZE(ch_data_type))
667 pr_info("WARN: invalid attribute settings\n");
668 return 0;
669}
670
671int most_set_cfg_direction(char *mdev, char *mdev_ch, char *buf)
672{
673 struct most_channel *c = get_channel(mdev, mdev_ch);
674
675 if (!c)
676 return -ENODEV;
677 if (!strcmp(buf, "dir_rx\n")) {
678 c->cfg.direction = MOST_CH_RX;
679 } else if (!strcmp(buf, "rx\n")) {
680 c->cfg.direction = MOST_CH_RX;
681 } else if (!strcmp(buf, "dir_tx\n")) {
682 c->cfg.direction = MOST_CH_TX;
683 } else if (!strcmp(buf, "tx\n")) {
684 c->cfg.direction = MOST_CH_TX;
685 } else {
686 pr_info("Invalid direction\n");
687 return -ENODATA;
688 }
689 return 0;
690}
691
692int most_set_cfg_packets_xact(char *mdev, char *mdev_ch, u16 val)
693{
694 struct most_channel *c = get_channel(mdev, mdev_ch);
695
696 if (!c)
697 return -ENODEV;
698 c->cfg.packets_per_xact = val;
699 return 0;
700}
701
702int most_cfg_complete(char *comp_name)
703{
704 struct core_component *comp;
705
706 comp = match_component(comp_name);
707 if (!comp)
708 return -ENODEV;
709
710 return comp->cfg_complete();
711}
712
713int most_add_link(char *mdev, char *mdev_ch, char *comp_name, char *link_name,
714 char *comp_param)
715{
716 struct most_channel *c = get_channel(mdev, mdev_ch);
717 struct core_component *comp = match_component(comp_name);
718
719 if (!c || !comp)
720 return -ENODEV;
721
722 return link_channel_to_component(c, comp, link_name, comp_param);
723}
724
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732
733static ssize_t remove_link_store(struct device_driver *drv,
734 const char *buf,
735 size_t len)
736{
737 struct most_channel *c;
738 struct core_component *comp;
739 char buffer[STRING_SIZE];
740 char *mdev;
741 char *mdev_ch;
742 char *comp_name;
743 int ret;
744 size_t max_len = min_t(size_t, len + 1, STRING_SIZE);
745
746 strlcpy(buffer, buf, max_len);
747 ret = split_string(buffer, &mdev, &mdev_ch, &comp_name, NULL);
748 if (ret)
749 return ret;
750 comp = match_component(comp_name);
751 if (!comp)
752 return -ENODEV;
753 c = get_channel(mdev, mdev_ch);
754 if (!c)
755 return -ENODEV;
756
757 if (comp->disconnect_channel(c->iface, c->channel_id))
758 return -EIO;
759 if (c->pipe0.comp == comp)
760 c->pipe0.comp = NULL;
761 if (c->pipe1.comp == comp)
762 c->pipe1.comp = NULL;
763 return len;
764}
765
766int most_remove_link(char *mdev, char *mdev_ch, char *comp_name)
767{
768 struct most_channel *c;
769 struct core_component *comp;
770
771 comp = match_component(comp_name);
772 if (!comp)
773 return -ENODEV;
774 c = get_channel(mdev, mdev_ch);
775 if (!c)
776 return -ENODEV;
777
778 if (comp->disconnect_channel(c->iface, c->channel_id))
779 return -EIO;
780 if (c->pipe0.comp == comp)
781 c->pipe0.comp = NULL;
782 if (c->pipe1.comp == comp)
783 c->pipe1.comp = NULL;
784 return 0;
785}
786
787#define DRV_ATTR(_name) (&driver_attr_##_name.attr)
788
789static DRIVER_ATTR_RO(links);
790static DRIVER_ATTR_RO(components);
791static DRIVER_ATTR_WO(remove_link);
792
793static struct attribute *mc_attrs[] = {
794 DRV_ATTR(links),
795 DRV_ATTR(components),
796 DRV_ATTR(remove_link),
797 NULL,
798};
799
800static struct attribute_group mc_attr_group = {
801 .attrs = mc_attrs,
802};
803
804static const struct attribute_group *mc_attr_groups[] = {
805 &mc_attr_group,
806 NULL,
807};
808
809static int most_match(struct device *dev, struct device_driver *drv)
810{
811 if (!strcmp(dev_name(dev), "most"))
812 return 0;
813 else
814 return 1;
815}
816
817static inline void trash_mbo(struct mbo *mbo)
818{
819 unsigned long flags;
820 struct most_channel *c = mbo->context;
821
822 spin_lock_irqsave(&c->fifo_lock, flags);
823 list_add(&mbo->list, &c->trash_fifo);
824 spin_unlock_irqrestore(&c->fifo_lock, flags);
825}
826
827static bool hdm_mbo_ready(struct most_channel *c)
828{
829 bool empty;
830
831 if (c->enqueue_halt)
832 return false;
833
834 spin_lock_irq(&c->fifo_lock);
835 empty = list_empty(&c->halt_fifo);
836 spin_unlock_irq(&c->fifo_lock);
837
838 return !empty;
839}
840
841static void nq_hdm_mbo(struct mbo *mbo)
842{
843 unsigned long flags;
844 struct most_channel *c = mbo->context;
845
846 spin_lock_irqsave(&c->fifo_lock, flags);
847 list_add_tail(&mbo->list, &c->halt_fifo);
848 spin_unlock_irqrestore(&c->fifo_lock, flags);
849 wake_up_interruptible(&c->hdm_fifo_wq);
850}
851
852static int hdm_enqueue_thread(void *data)
853{
854 struct most_channel *c = data;
855 struct mbo *mbo;
856 int ret;
857 typeof(c->iface->enqueue) enqueue = c->iface->enqueue;
858
859 while (likely(!kthread_should_stop())) {
860 wait_event_interruptible(c->hdm_fifo_wq,
861 hdm_mbo_ready(c) ||
862 kthread_should_stop());
863
864 mutex_lock(&c->nq_mutex);
865 spin_lock_irq(&c->fifo_lock);
866 if (unlikely(c->enqueue_halt || list_empty(&c->halt_fifo))) {
867 spin_unlock_irq(&c->fifo_lock);
868 mutex_unlock(&c->nq_mutex);
869 continue;
870 }
871
872 mbo = list_pop_mbo(&c->halt_fifo);
873 spin_unlock_irq(&c->fifo_lock);
874
875 if (c->cfg.direction == MOST_CH_RX)
876 mbo->buffer_length = c->cfg.buffer_size;
877
878 ret = enqueue(mbo->ifp, mbo->hdm_channel_id, mbo);
879 mutex_unlock(&c->nq_mutex);
880
881 if (unlikely(ret)) {
882 pr_err("hdm enqueue failed\n");
883 nq_hdm_mbo(mbo);
884 c->hdm_enqueue_task = NULL;
885 return 0;
886 }
887 }
888
889 return 0;
890}
891
892static int run_enqueue_thread(struct most_channel *c, int channel_id)
893{
894 struct task_struct *task =
895 kthread_run(hdm_enqueue_thread, c, "hdm_fifo_%d",
896 channel_id);
897
898 if (IS_ERR(task))
899 return PTR_ERR(task);
900
901 c->hdm_enqueue_task = task;
902 return 0;
903}
904
905
906
907
908
909
910
911
912
913
914
915
916static void arm_mbo(struct mbo *mbo)
917{
918 unsigned long flags;
919 struct most_channel *c;
920
921 c = mbo->context;
922
923 if (c->is_poisoned) {
924 trash_mbo(mbo);
925 return;
926 }
927
928 spin_lock_irqsave(&c->fifo_lock, flags);
929 ++*mbo->num_buffers_ptr;
930 list_add_tail(&mbo->list, &c->fifo);
931 spin_unlock_irqrestore(&c->fifo_lock, flags);
932
933 if (c->pipe0.refs && c->pipe0.comp->tx_completion)
934 c->pipe0.comp->tx_completion(c->iface, c->channel_id);
935
936 if (c->pipe1.refs && c->pipe1.comp->tx_completion)
937 c->pipe1.comp->tx_completion(c->iface, c->channel_id);
938}
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953static int arm_mbo_chain(struct most_channel *c, int dir,
954 void (*compl)(struct mbo *))
955{
956 unsigned int i;
957 struct mbo *mbo;
958 unsigned long flags;
959 u32 coherent_buf_size = c->cfg.buffer_size + c->cfg.extra_len;
960
961 atomic_set(&c->mbo_nq_level, 0);
962
963 for (i = 0; i < c->cfg.num_buffers; i++) {
964 mbo = kzalloc(sizeof(*mbo), GFP_KERNEL);
965 if (!mbo)
966 goto flush_fifos;
967
968 mbo->context = c;
969 mbo->ifp = c->iface;
970 mbo->hdm_channel_id = c->channel_id;
971 if (c->iface->dma_alloc) {
972 mbo->virt_address =
973 c->iface->dma_alloc(mbo, coherent_buf_size);
974 } else {
975 mbo->virt_address =
976 kzalloc(coherent_buf_size, GFP_KERNEL);
977 }
978 if (!mbo->virt_address)
979 goto release_mbo;
980
981 mbo->complete = compl;
982 mbo->num_buffers_ptr = &dummy_num_buffers;
983 if (dir == MOST_CH_RX) {
984 nq_hdm_mbo(mbo);
985 atomic_inc(&c->mbo_nq_level);
986 } else {
987 spin_lock_irqsave(&c->fifo_lock, flags);
988 list_add_tail(&mbo->list, &c->fifo);
989 spin_unlock_irqrestore(&c->fifo_lock, flags);
990 }
991 }
992 return c->cfg.num_buffers;
993
994release_mbo:
995 kfree(mbo);
996
997flush_fifos:
998 flush_channel_fifos(c);
999 return 0;
1000}
1001
1002
1003
1004
1005
1006void most_submit_mbo(struct mbo *mbo)
1007{
1008 if (WARN_ONCE(!mbo || !mbo->context,
1009 "bad mbo or missing channel reference\n"))
1010 return;
1011
1012 nq_hdm_mbo(mbo);
1013}
1014EXPORT_SYMBOL_GPL(most_submit_mbo);
1015
1016
1017
1018
1019
1020
1021
1022
1023static void most_write_completion(struct mbo *mbo)
1024{
1025 struct most_channel *c;
1026
1027 c = mbo->context;
1028 if (mbo->status == MBO_E_INVAL)
1029 pr_info("WARN: Tx MBO status: invalid\n");
1030 if (unlikely(c->is_poisoned || (mbo->status == MBO_E_CLOSE)))
1031 trash_mbo(mbo);
1032 else
1033 arm_mbo(mbo);
1034}
1035
1036int channel_has_mbo(struct most_interface *iface, int id,
1037 struct core_component *comp)
1038{
1039 struct most_channel *c = iface->p->channel[id];
1040 unsigned long flags;
1041 int empty;
1042
1043 if (unlikely(!c))
1044 return -EINVAL;
1045
1046 if (c->pipe0.refs && c->pipe1.refs &&
1047 ((comp == c->pipe0.comp && c->pipe0.num_buffers <= 0) ||
1048 (comp == c->pipe1.comp && c->pipe1.num_buffers <= 0)))
1049 return 0;
1050
1051 spin_lock_irqsave(&c->fifo_lock, flags);
1052 empty = list_empty(&c->fifo);
1053 spin_unlock_irqrestore(&c->fifo_lock, flags);
1054 return !empty;
1055}
1056EXPORT_SYMBOL_GPL(channel_has_mbo);
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067struct mbo *most_get_mbo(struct most_interface *iface, int id,
1068 struct core_component *comp)
1069{
1070 struct mbo *mbo;
1071 struct most_channel *c;
1072 unsigned long flags;
1073 int *num_buffers_ptr;
1074
1075 c = iface->p->channel[id];
1076 if (unlikely(!c))
1077 return NULL;
1078
1079 if (c->pipe0.refs && c->pipe1.refs &&
1080 ((comp == c->pipe0.comp && c->pipe0.num_buffers <= 0) ||
1081 (comp == c->pipe1.comp && c->pipe1.num_buffers <= 0)))
1082 return NULL;
1083
1084 if (comp == c->pipe0.comp)
1085 num_buffers_ptr = &c->pipe0.num_buffers;
1086 else if (comp == c->pipe1.comp)
1087 num_buffers_ptr = &c->pipe1.num_buffers;
1088 else
1089 num_buffers_ptr = &dummy_num_buffers;
1090
1091 spin_lock_irqsave(&c->fifo_lock, flags);
1092 if (list_empty(&c->fifo)) {
1093 spin_unlock_irqrestore(&c->fifo_lock, flags);
1094 return NULL;
1095 }
1096 mbo = list_pop_mbo(&c->fifo);
1097 --*num_buffers_ptr;
1098 spin_unlock_irqrestore(&c->fifo_lock, flags);
1099
1100 mbo->num_buffers_ptr = num_buffers_ptr;
1101 mbo->buffer_length = c->cfg.buffer_size;
1102 return mbo;
1103}
1104EXPORT_SYMBOL_GPL(most_get_mbo);
1105
1106
1107
1108
1109
1110void most_put_mbo(struct mbo *mbo)
1111{
1112 struct most_channel *c = mbo->context;
1113
1114 if (c->cfg.direction == MOST_CH_TX) {
1115 arm_mbo(mbo);
1116 return;
1117 }
1118 nq_hdm_mbo(mbo);
1119 atomic_inc(&c->mbo_nq_level);
1120}
1121EXPORT_SYMBOL_GPL(most_put_mbo);
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133static void most_read_completion(struct mbo *mbo)
1134{
1135 struct most_channel *c = mbo->context;
1136
1137 if (unlikely(c->is_poisoned || (mbo->status == MBO_E_CLOSE))) {
1138 trash_mbo(mbo);
1139 return;
1140 }
1141
1142 if (mbo->status == MBO_E_INVAL) {
1143 nq_hdm_mbo(mbo);
1144 atomic_inc(&c->mbo_nq_level);
1145 return;
1146 }
1147
1148 if (atomic_sub_and_test(1, &c->mbo_nq_level))
1149 c->is_starving = 1;
1150
1151 if (c->pipe0.refs && c->pipe0.comp->rx_completion &&
1152 c->pipe0.comp->rx_completion(mbo) == 0)
1153 return;
1154
1155 if (c->pipe1.refs && c->pipe1.comp->rx_completion &&
1156 c->pipe1.comp->rx_completion(mbo) == 0)
1157 return;
1158
1159 most_put_mbo(mbo);
1160}
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173int most_start_channel(struct most_interface *iface, int id,
1174 struct core_component *comp)
1175{
1176 int num_buffer;
1177 int ret;
1178 struct most_channel *c = iface->p->channel[id];
1179
1180 if (unlikely(!c))
1181 return -EINVAL;
1182
1183 mutex_lock(&c->start_mutex);
1184 if (c->pipe0.refs + c->pipe1.refs > 0)
1185 goto out;
1186
1187 if (!try_module_get(iface->mod)) {
1188 pr_info("failed to acquire HDM lock\n");
1189 mutex_unlock(&c->start_mutex);
1190 return -ENOLCK;
1191 }
1192
1193 c->cfg.extra_len = 0;
1194 if (c->iface->configure(c->iface, c->channel_id, &c->cfg)) {
1195 pr_info("channel configuration failed. Go check settings...\n");
1196 ret = -EINVAL;
1197 goto err_put_module;
1198 }
1199
1200 init_waitqueue_head(&c->hdm_fifo_wq);
1201
1202 if (c->cfg.direction == MOST_CH_RX)
1203 num_buffer = arm_mbo_chain(c, c->cfg.direction,
1204 most_read_completion);
1205 else
1206 num_buffer = arm_mbo_chain(c, c->cfg.direction,
1207 most_write_completion);
1208 if (unlikely(!num_buffer)) {
1209 ret = -ENOMEM;
1210 goto err_put_module;
1211 }
1212
1213 ret = run_enqueue_thread(c, id);
1214 if (ret)
1215 goto err_put_module;
1216
1217 c->is_starving = 0;
1218 c->pipe0.num_buffers = c->cfg.num_buffers / 2;
1219 c->pipe1.num_buffers = c->cfg.num_buffers - c->pipe0.num_buffers;
1220 atomic_set(&c->mbo_ref, num_buffer);
1221
1222out:
1223 if (comp == c->pipe0.comp)
1224 c->pipe0.refs++;
1225 if (comp == c->pipe1.comp)
1226 c->pipe1.refs++;
1227 mutex_unlock(&c->start_mutex);
1228 return 0;
1229
1230err_put_module:
1231 module_put(iface->mod);
1232 mutex_unlock(&c->start_mutex);
1233 return ret;
1234}
1235EXPORT_SYMBOL_GPL(most_start_channel);
1236
1237
1238
1239
1240
1241
1242
1243int most_stop_channel(struct most_interface *iface, int id,
1244 struct core_component *comp)
1245{
1246 struct most_channel *c;
1247
1248 if (unlikely((!iface) || (id >= iface->num_channels) || (id < 0))) {
1249 pr_err("Bad interface or index out of range\n");
1250 return -EINVAL;
1251 }
1252 c = iface->p->channel[id];
1253 if (unlikely(!c))
1254 return -EINVAL;
1255
1256 mutex_lock(&c->start_mutex);
1257 if (c->pipe0.refs + c->pipe1.refs >= 2)
1258 goto out;
1259
1260 if (c->hdm_enqueue_task)
1261 kthread_stop(c->hdm_enqueue_task);
1262 c->hdm_enqueue_task = NULL;
1263
1264 if (iface->mod)
1265 module_put(iface->mod);
1266
1267 c->is_poisoned = true;
1268 if (c->iface->poison_channel(c->iface, c->channel_id)) {
1269 pr_err("Cannot stop channel %d of mdev %s\n", c->channel_id,
1270 c->iface->description);
1271 mutex_unlock(&c->start_mutex);
1272 return -EAGAIN;
1273 }
1274 flush_trash_fifo(c);
1275 flush_channel_fifos(c);
1276
1277#ifdef CMPL_INTERRUPTIBLE
1278 if (wait_for_completion_interruptible(&c->cleanup)) {
1279 pr_info("Interrupted while clean up ch %d\n", c->channel_id);
1280 mutex_unlock(&c->start_mutex);
1281 return -EINTR;
1282 }
1283#else
1284 wait_for_completion(&c->cleanup);
1285#endif
1286 c->is_poisoned = false;
1287
1288out:
1289 if (comp == c->pipe0.comp)
1290 c->pipe0.refs--;
1291 if (comp == c->pipe1.comp)
1292 c->pipe1.refs--;
1293 mutex_unlock(&c->start_mutex);
1294 return 0;
1295}
1296EXPORT_SYMBOL_GPL(most_stop_channel);
1297
1298
1299
1300
1301
1302int most_register_component(struct core_component *comp)
1303{
1304 if (!comp) {
1305 pr_err("Bad component\n");
1306 return -EINVAL;
1307 }
1308 list_add_tail(&comp->list, &mc.comp_list);
1309 pr_info("registered new core component %s\n", comp->name);
1310 return 0;
1311}
1312EXPORT_SYMBOL_GPL(most_register_component);
1313
1314static int disconnect_channels(struct device *dev, void *data)
1315{
1316 struct most_interface *iface;
1317 struct most_channel *c, *tmp;
1318 struct core_component *comp = data;
1319
1320 iface = to_most_interface(dev);
1321 list_for_each_entry_safe(c, tmp, &iface->p->channel_list, list) {
1322 if (c->pipe0.comp == comp || c->pipe1.comp == comp)
1323 comp->disconnect_channel(c->iface, c->channel_id);
1324 if (c->pipe0.comp == comp)
1325 c->pipe0.comp = NULL;
1326 if (c->pipe1.comp == comp)
1327 c->pipe1.comp = NULL;
1328 }
1329 return 0;
1330}
1331
1332
1333
1334
1335
1336int most_deregister_component(struct core_component *comp)
1337{
1338 if (!comp) {
1339 pr_err("Bad component\n");
1340 return -EINVAL;
1341 }
1342
1343 bus_for_each_dev(&mc.bus, NULL, comp, disconnect_channels);
1344 list_del(&comp->list);
1345 pr_info("deregistering component %s\n", comp->name);
1346 return 0;
1347}
1348EXPORT_SYMBOL_GPL(most_deregister_component);
1349
1350static void release_interface(struct device *dev)
1351{
1352 pr_info("releasing interface dev %s...\n", dev_name(dev));
1353}
1354
1355static void release_channel(struct device *dev)
1356{
1357 pr_info("releasing channel dev %s...\n", dev_name(dev));
1358}
1359
1360
1361
1362
1363
1364
1365
1366
1367int most_register_interface(struct most_interface *iface)
1368{
1369 unsigned int i;
1370 int id;
1371 struct most_channel *c;
1372
1373 if (!iface || !iface->enqueue || !iface->configure ||
1374 !iface->poison_channel || (iface->num_channels > MAX_CHANNELS)) {
1375 pr_err("Bad interface or channel overflow\n");
1376 return -EINVAL;
1377 }
1378
1379 id = ida_simple_get(&mdev_id, 0, 0, GFP_KERNEL);
1380 if (id < 0) {
1381 pr_info("Failed to alloc mdev ID\n");
1382 return id;
1383 }
1384
1385 iface->p = kzalloc(sizeof(*iface->p), GFP_KERNEL);
1386 if (!iface->p) {
1387 ida_simple_remove(&mdev_id, id);
1388 return -ENOMEM;
1389 }
1390
1391 INIT_LIST_HEAD(&iface->p->channel_list);
1392 iface->p->dev_id = id;
1393 strscpy(iface->p->name, iface->description, sizeof(iface->p->name));
1394 iface->dev.init_name = iface->p->name;
1395 iface->dev.bus = &mc.bus;
1396 iface->dev.parent = &mc.dev;
1397 iface->dev.groups = interface_attr_groups;
1398 iface->dev.release = release_interface;
1399 if (device_register(&iface->dev)) {
1400 pr_err("registering iface->dev failed\n");
1401 kfree(iface->p);
1402 ida_simple_remove(&mdev_id, id);
1403 return -ENOMEM;
1404 }
1405
1406 for (i = 0; i < iface->num_channels; i++) {
1407 const char *name_suffix = iface->channel_vector[i].name_suffix;
1408
1409 c = kzalloc(sizeof(*c), GFP_KERNEL);
1410 if (!c)
1411 goto err_free_resources;
1412 if (!name_suffix)
1413 snprintf(c->name, STRING_SIZE, "ch%d", i);
1414 else
1415 snprintf(c->name, STRING_SIZE, "%s", name_suffix);
1416 c->dev.init_name = c->name;
1417 c->dev.parent = &iface->dev;
1418 c->dev.groups = channel_attr_groups;
1419 c->dev.release = release_channel;
1420 iface->p->channel[i] = c;
1421 c->is_starving = 0;
1422 c->iface = iface;
1423 c->channel_id = i;
1424 c->keep_mbo = false;
1425 c->enqueue_halt = false;
1426 c->is_poisoned = false;
1427 c->cfg.direction = 0;
1428 c->cfg.data_type = 0;
1429 c->cfg.num_buffers = 0;
1430 c->cfg.buffer_size = 0;
1431 c->cfg.subbuffer_size = 0;
1432 c->cfg.packets_per_xact = 0;
1433 spin_lock_init(&c->fifo_lock);
1434 INIT_LIST_HEAD(&c->fifo);
1435 INIT_LIST_HEAD(&c->trash_fifo);
1436 INIT_LIST_HEAD(&c->halt_fifo);
1437 init_completion(&c->cleanup);
1438 atomic_set(&c->mbo_ref, 0);
1439 mutex_init(&c->start_mutex);
1440 mutex_init(&c->nq_mutex);
1441 list_add_tail(&c->list, &iface->p->channel_list);
1442 if (device_register(&c->dev)) {
1443 pr_err("registering c->dev failed\n");
1444 goto err_free_most_channel;
1445 }
1446 }
1447 pr_info("registered new device mdev%d (%s)\n",
1448 id, iface->description);
1449 most_interface_register_notify(iface->description);
1450 return 0;
1451
1452err_free_most_channel:
1453 kfree(c);
1454
1455err_free_resources:
1456 while (i > 0) {
1457 c = iface->p->channel[--i];
1458 device_unregister(&c->dev);
1459 kfree(c);
1460 }
1461 kfree(iface->p);
1462 device_unregister(&iface->dev);
1463 ida_simple_remove(&mdev_id, id);
1464 return -ENOMEM;
1465}
1466EXPORT_SYMBOL_GPL(most_register_interface);
1467
1468
1469
1470
1471
1472
1473
1474
1475void most_deregister_interface(struct most_interface *iface)
1476{
1477 int i;
1478 struct most_channel *c;
1479
1480 pr_info("deregistering device %s (%s)\n", dev_name(&iface->dev),
1481 iface->description);
1482 for (i = 0; i < iface->num_channels; i++) {
1483 c = iface->p->channel[i];
1484 if (c->pipe0.comp)
1485 c->pipe0.comp->disconnect_channel(c->iface,
1486 c->channel_id);
1487 if (c->pipe1.comp)
1488 c->pipe1.comp->disconnect_channel(c->iface,
1489 c->channel_id);
1490 c->pipe0.comp = NULL;
1491 c->pipe1.comp = NULL;
1492 list_del(&c->list);
1493 device_unregister(&c->dev);
1494 kfree(c);
1495 }
1496
1497 ida_simple_remove(&mdev_id, iface->p->dev_id);
1498 kfree(iface->p);
1499 device_unregister(&iface->dev);
1500}
1501EXPORT_SYMBOL_GPL(most_deregister_interface);
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513void most_stop_enqueue(struct most_interface *iface, int id)
1514{
1515 struct most_channel *c = iface->p->channel[id];
1516
1517 if (!c)
1518 return;
1519
1520 mutex_lock(&c->nq_mutex);
1521 c->enqueue_halt = true;
1522 mutex_unlock(&c->nq_mutex);
1523}
1524EXPORT_SYMBOL_GPL(most_stop_enqueue);
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534void most_resume_enqueue(struct most_interface *iface, int id)
1535{
1536 struct most_channel *c = iface->p->channel[id];
1537
1538 if (!c)
1539 return;
1540
1541 mutex_lock(&c->nq_mutex);
1542 c->enqueue_halt = false;
1543 mutex_unlock(&c->nq_mutex);
1544
1545 wake_up_interruptible(&c->hdm_fifo_wq);
1546}
1547EXPORT_SYMBOL_GPL(most_resume_enqueue);
1548
1549static void release_most_sub(struct device *dev)
1550{
1551 pr_info("releasing most_subsystem\n");
1552}
1553
1554static int __init most_init(void)
1555{
1556 int err;
1557
1558 pr_info("init()\n");
1559 INIT_LIST_HEAD(&mc.comp_list);
1560 ida_init(&mdev_id);
1561
1562 mc.bus.name = "most",
1563 mc.bus.match = most_match,
1564 mc.drv.name = "most_core",
1565 mc.drv.bus = &mc.bus,
1566 mc.drv.groups = mc_attr_groups;
1567
1568 err = bus_register(&mc.bus);
1569 if (err) {
1570 pr_info("Cannot register most bus\n");
1571 return err;
1572 }
1573 err = driver_register(&mc.drv);
1574 if (err) {
1575 pr_info("Cannot register core driver\n");
1576 goto err_unregister_bus;
1577 }
1578 mc.dev.init_name = "most_bus";
1579 mc.dev.release = release_most_sub;
1580 if (device_register(&mc.dev)) {
1581 err = -ENOMEM;
1582 goto err_unregister_driver;
1583 }
1584 configfs_init();
1585 return 0;
1586
1587err_unregister_driver:
1588 driver_unregister(&mc.drv);
1589err_unregister_bus:
1590 bus_unregister(&mc.bus);
1591 return err;
1592}
1593
1594static void __exit most_exit(void)
1595{
1596 pr_info("exit core module\n");
1597 device_unregister(&mc.dev);
1598 driver_unregister(&mc.drv);
1599 bus_unregister(&mc.bus);
1600 ida_destroy(&mdev_id);
1601}
1602
1603module_init(most_init);
1604module_exit(most_exit);
1605MODULE_LICENSE("GPL");
1606MODULE_AUTHOR("Christian Gromm <christian.gromm@microchip.com>");
1607MODULE_DESCRIPTION("Core module of stacked MOST Linux driver");
1608