xref: /kernel/linux/linux-6.6/drivers/most/most_usb.c (revision 62306a36)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * usb.c - Hardware dependent module for USB
4 *
5 * Copyright (C) 2013-2015 Microchip Technology Germany II GmbH & Co. KG
6 */
7
8#include <linux/module.h>
9#include <linux/fs.h>
10#include <linux/usb.h>
11#include <linux/slab.h>
12#include <linux/init.h>
13#include <linux/cdev.h>
14#include <linux/device.h>
15#include <linux/list.h>
16#include <linux/completion.h>
17#include <linux/mutex.h>
18#include <linux/spinlock.h>
19#include <linux/interrupt.h>
20#include <linux/workqueue.h>
21#include <linux/sysfs.h>
22#include <linux/dma-mapping.h>
23#include <linux/etherdevice.h>
24#include <linux/uaccess.h>
25#include <linux/most.h>
26
27#define USB_MTU			512
28#define NO_ISOCHRONOUS_URB	0
29#define AV_PACKETS_PER_XACT	2
30#define BUF_CHAIN_SIZE		0xFFFF
31#define MAX_NUM_ENDPOINTS	30
32#define MAX_SUFFIX_LEN		10
33#define MAX_STRING_LEN		80
34#define MAX_BUF_SIZE		0xFFFF
35
36#define USB_VENDOR_ID_SMSC	0x0424  /* VID: SMSC */
37#define USB_DEV_ID_BRDG		0xC001  /* PID: USB Bridge */
38#define USB_DEV_ID_OS81118	0xCF18  /* PID: USB OS81118 */
39#define USB_DEV_ID_OS81119	0xCF19  /* PID: USB OS81119 */
40#define USB_DEV_ID_OS81210	0xCF30  /* PID: USB OS81210 */
41/* DRCI Addresses */
42#define DRCI_REG_NI_STATE	0x0100
43#define DRCI_REG_PACKET_BW	0x0101
44#define DRCI_REG_NODE_ADDR	0x0102
45#define DRCI_REG_NODE_POS	0x0103
46#define DRCI_REG_MEP_FILTER	0x0140
47#define DRCI_REG_HASH_TBL0	0x0141
48#define DRCI_REG_HASH_TBL1	0x0142
49#define DRCI_REG_HASH_TBL2	0x0143
50#define DRCI_REG_HASH_TBL3	0x0144
51#define DRCI_REG_HW_ADDR_HI	0x0145
52#define DRCI_REG_HW_ADDR_MI	0x0146
53#define DRCI_REG_HW_ADDR_LO	0x0147
54#define DRCI_REG_BASE		0x1100
55#define DRCI_COMMAND		0x02
56#define DRCI_READ_REQ		0xA0
57#define DRCI_WRITE_REQ		0xA1
58
59/**
60 * struct most_dci_obj - Direct Communication Interface
61 * @kobj:position in sysfs
62 * @usb_device: pointer to the usb device
63 * @reg_addr: register address for arbitrary DCI access
64 */
65struct most_dci_obj {
66	struct device dev;
67	struct usb_device *usb_device;
68	u16 reg_addr;
69};
70
71#define to_dci_obj(p) container_of(p, struct most_dci_obj, dev)
72
73struct most_dev;
74
75struct clear_hold_work {
76	struct work_struct ws;
77	struct most_dev *mdev;
78	unsigned int channel;
79	int pipe;
80};
81
82#define to_clear_hold_work(w) container_of(w, struct clear_hold_work, ws)
83
84/**
85 * struct most_dev - holds all usb interface specific stuff
86 * @usb_device: pointer to usb device
87 * @iface: hardware interface
88 * @cap: channel capabilities
89 * @conf: channel configuration
90 * @dci: direct communication interface of hardware
91 * @ep_address: endpoint address table
92 * @description: device description
93 * @suffix: suffix for channel name
94 * @channel_lock: synchronize channel access
95 * @padding_active: indicates channel uses padding
96 * @is_channel_healthy: health status table of each channel
97 * @busy_urbs: list of anchored items
98 * @io_mutex: synchronize I/O with disconnect
99 * @link_stat_timer: timer for link status reports
100 * @poll_work_obj: work for polling link status
101 */
102struct most_dev {
103	struct device dev;
104	struct usb_device *usb_device;
105	struct most_interface iface;
106	struct most_channel_capability *cap;
107	struct most_channel_config *conf;
108	struct most_dci_obj *dci;
109	u8 *ep_address;
110	char description[MAX_STRING_LEN];
111	char suffix[MAX_NUM_ENDPOINTS][MAX_SUFFIX_LEN];
112	spinlock_t channel_lock[MAX_NUM_ENDPOINTS]; /* sync channel access */
113	bool padding_active[MAX_NUM_ENDPOINTS];
114	bool is_channel_healthy[MAX_NUM_ENDPOINTS];
115	struct clear_hold_work clear_work[MAX_NUM_ENDPOINTS];
116	struct usb_anchor *busy_urbs;
117	struct mutex io_mutex;
118	struct timer_list link_stat_timer;
119	struct work_struct poll_work_obj;
120	void (*on_netinfo)(struct most_interface *most_iface,
121			   unsigned char link_state, unsigned char *addrs);
122};
123
124#define to_mdev(d) container_of(d, struct most_dev, iface)
125#define to_mdev_from_dev(d) container_of(d, struct most_dev, dev)
126#define to_mdev_from_work(w) container_of(w, struct most_dev, poll_work_obj)
127
128static void wq_clear_halt(struct work_struct *wq_obj);
129static void wq_netinfo(struct work_struct *wq_obj);
130
131/**
132 * drci_rd_reg - read a DCI register
133 * @dev: usb device
134 * @reg: register address
135 * @buf: buffer to store data
136 *
137 * This is reads data from INIC's direct register communication interface
138 */
139static inline int drci_rd_reg(struct usb_device *dev, u16 reg, u16 *buf)
140{
141	int retval;
142	__le16 *dma_buf;
143	u8 req_type = USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE;
144
145	dma_buf = kzalloc(sizeof(*dma_buf), GFP_KERNEL);
146	if (!dma_buf)
147		return -ENOMEM;
148
149	retval = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
150				 DRCI_READ_REQ, req_type,
151				 0x0000,
152				 reg, dma_buf, sizeof(*dma_buf),
153				 USB_CTRL_GET_TIMEOUT);
154	*buf = le16_to_cpu(*dma_buf);
155	kfree(dma_buf);
156
157	if (retval < 0)
158		return retval;
159	return 0;
160}
161
162/**
163 * drci_wr_reg - write a DCI register
164 * @dev: usb device
165 * @reg: register address
166 * @data: data to write
167 *
168 * This is writes data to INIC's direct register communication interface
169 */
170static inline int drci_wr_reg(struct usb_device *dev, u16 reg, u16 data)
171{
172	return usb_control_msg(dev,
173			       usb_sndctrlpipe(dev, 0),
174			       DRCI_WRITE_REQ,
175			       USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
176			       data,
177			       reg,
178			       NULL,
179			       0,
180			       USB_CTRL_SET_TIMEOUT);
181}
182
183static inline int start_sync_ep(struct usb_device *usb_dev, u16 ep)
184{
185	return drci_wr_reg(usb_dev, DRCI_REG_BASE + DRCI_COMMAND + ep * 16, 1);
186}
187
188/**
189 * get_stream_frame_size - calculate frame size of current configuration
190 * @dev: device structure
191 * @cfg: channel configuration
192 */
193static unsigned int get_stream_frame_size(struct device *dev,
194					  struct most_channel_config *cfg)
195{
196	unsigned int frame_size;
197	unsigned int sub_size = cfg->subbuffer_size;
198
199	if (!sub_size) {
200		dev_warn(dev, "Misconfig: Subbuffer size zero.\n");
201		return 0;
202	}
203	switch (cfg->data_type) {
204	case MOST_CH_ISOC:
205		frame_size = AV_PACKETS_PER_XACT * sub_size;
206		break;
207	case MOST_CH_SYNC:
208		if (cfg->packets_per_xact == 0) {
209			dev_warn(dev, "Misconfig: Packets per XACT zero\n");
210			frame_size = 0;
211		} else if (cfg->packets_per_xact == 0xFF) {
212			frame_size = (USB_MTU / sub_size) * sub_size;
213		} else {
214			frame_size = cfg->packets_per_xact * sub_size;
215		}
216		break;
217	default:
218		dev_warn(dev, "Query frame size of non-streaming channel\n");
219		frame_size = 0;
220		break;
221	}
222	return frame_size;
223}
224
225/**
226 * hdm_poison_channel - mark buffers of this channel as invalid
227 * @iface: pointer to the interface
228 * @channel: channel ID
229 *
230 * This unlinks all URBs submitted to the HCD,
231 * calls the associated completion function of the core and removes
232 * them from the list.
233 *
234 * Returns 0 on success or error code otherwise.
235 */
236static int hdm_poison_channel(struct most_interface *iface, int channel)
237{
238	struct most_dev *mdev = to_mdev(iface);
239	unsigned long flags;
240	spinlock_t *lock; /* temp. lock */
241
242	if (channel < 0 || channel >= iface->num_channels) {
243		dev_warn(&mdev->usb_device->dev, "Channel ID out of range.\n");
244		return -ECHRNG;
245	}
246
247	lock = mdev->channel_lock + channel;
248	spin_lock_irqsave(lock, flags);
249	mdev->is_channel_healthy[channel] = false;
250	spin_unlock_irqrestore(lock, flags);
251
252	cancel_work_sync(&mdev->clear_work[channel].ws);
253
254	mutex_lock(&mdev->io_mutex);
255	usb_kill_anchored_urbs(&mdev->busy_urbs[channel]);
256	if (mdev->padding_active[channel])
257		mdev->padding_active[channel] = false;
258
259	if (mdev->conf[channel].data_type == MOST_CH_ASYNC) {
260		del_timer_sync(&mdev->link_stat_timer);
261		cancel_work_sync(&mdev->poll_work_obj);
262	}
263	mutex_unlock(&mdev->io_mutex);
264	return 0;
265}
266
267/**
268 * hdm_add_padding - add padding bytes
269 * @mdev: most device
270 * @channel: channel ID
271 * @mbo: buffer object
272 *
273 * This inserts the INIC hardware specific padding bytes into a streaming
274 * channel's buffer
275 */
276static int hdm_add_padding(struct most_dev *mdev, int channel, struct mbo *mbo)
277{
278	struct most_channel_config *conf = &mdev->conf[channel];
279	unsigned int frame_size = get_stream_frame_size(&mdev->dev, conf);
280	unsigned int j, num_frames;
281
282	if (!frame_size)
283		return -EINVAL;
284	num_frames = mbo->buffer_length / frame_size;
285
286	if (num_frames < 1) {
287		dev_err(&mdev->usb_device->dev,
288			"Missed minimal transfer unit.\n");
289		return -EINVAL;
290	}
291
292	for (j = num_frames - 1; j > 0; j--)
293		memmove(mbo->virt_address + j * USB_MTU,
294			mbo->virt_address + j * frame_size,
295			frame_size);
296	mbo->buffer_length = num_frames * USB_MTU;
297	return 0;
298}
299
300/**
301 * hdm_remove_padding - remove padding bytes
302 * @mdev: most device
303 * @channel: channel ID
304 * @mbo: buffer object
305 *
306 * This takes the INIC hardware specific padding bytes off a streaming
307 * channel's buffer.
308 */
309static int hdm_remove_padding(struct most_dev *mdev, int channel,
310			      struct mbo *mbo)
311{
312	struct most_channel_config *const conf = &mdev->conf[channel];
313	unsigned int frame_size = get_stream_frame_size(&mdev->dev, conf);
314	unsigned int j, num_frames;
315
316	if (!frame_size)
317		return -EINVAL;
318	num_frames = mbo->processed_length / USB_MTU;
319
320	for (j = 1; j < num_frames; j++)
321		memmove(mbo->virt_address + frame_size * j,
322			mbo->virt_address + USB_MTU * j,
323			frame_size);
324
325	mbo->processed_length = frame_size * num_frames;
326	return 0;
327}
328
329/**
330 * hdm_write_completion - completion function for submitted Tx URBs
331 * @urb: the URB that has been completed
332 *
333 * This checks the status of the completed URB. In case the URB has been
334 * unlinked before, it is immediately freed. On any other error the MBO
335 * transfer flag is set. On success it frees allocated resources and calls
336 * the completion function.
337 *
338 * Context: interrupt!
339 */
340static void hdm_write_completion(struct urb *urb)
341{
342	struct mbo *mbo = urb->context;
343	struct most_dev *mdev = to_mdev(mbo->ifp);
344	unsigned int channel = mbo->hdm_channel_id;
345	spinlock_t *lock = mdev->channel_lock + channel;
346	unsigned long flags;
347
348	spin_lock_irqsave(lock, flags);
349
350	mbo->processed_length = 0;
351	mbo->status = MBO_E_INVAL;
352	if (likely(mdev->is_channel_healthy[channel])) {
353		switch (urb->status) {
354		case 0:
355		case -ESHUTDOWN:
356			mbo->processed_length = urb->actual_length;
357			mbo->status = MBO_SUCCESS;
358			break;
359		case -EPIPE:
360			dev_warn(&mdev->usb_device->dev,
361				 "Broken pipe on ep%02x\n",
362				 mdev->ep_address[channel]);
363			mdev->is_channel_healthy[channel] = false;
364			mdev->clear_work[channel].pipe = urb->pipe;
365			schedule_work(&mdev->clear_work[channel].ws);
366			break;
367		case -ENODEV:
368		case -EPROTO:
369			mbo->status = MBO_E_CLOSE;
370			break;
371		}
372	}
373
374	spin_unlock_irqrestore(lock, flags);
375
376	if (likely(mbo->complete))
377		mbo->complete(mbo);
378	usb_free_urb(urb);
379}
380
381/**
382 * hdm_read_completion - completion function for submitted Rx URBs
383 * @urb: the URB that has been completed
384 *
385 * This checks the status of the completed URB. In case the URB has been
386 * unlinked before it is immediately freed. On any other error the MBO transfer
387 * flag is set. On success it frees allocated resources, removes
388 * padding bytes -if necessary- and calls the completion function.
389 *
390 * Context: interrupt!
391 */
392static void hdm_read_completion(struct urb *urb)
393{
394	struct mbo *mbo = urb->context;
395	struct most_dev *mdev = to_mdev(mbo->ifp);
396	unsigned int channel = mbo->hdm_channel_id;
397	struct device *dev = &mdev->usb_device->dev;
398	spinlock_t *lock = mdev->channel_lock + channel;
399	unsigned long flags;
400
401	spin_lock_irqsave(lock, flags);
402
403	mbo->processed_length = 0;
404	mbo->status = MBO_E_INVAL;
405	if (likely(mdev->is_channel_healthy[channel])) {
406		switch (urb->status) {
407		case 0:
408		case -ESHUTDOWN:
409			mbo->processed_length = urb->actual_length;
410			mbo->status = MBO_SUCCESS;
411			if (mdev->padding_active[channel] &&
412			    hdm_remove_padding(mdev, channel, mbo)) {
413				mbo->processed_length = 0;
414				mbo->status = MBO_E_INVAL;
415			}
416			break;
417		case -EPIPE:
418			dev_warn(dev, "Broken pipe on ep%02x\n",
419				 mdev->ep_address[channel]);
420			mdev->is_channel_healthy[channel] = false;
421			mdev->clear_work[channel].pipe = urb->pipe;
422			schedule_work(&mdev->clear_work[channel].ws);
423			break;
424		case -ENODEV:
425		case -EPROTO:
426			mbo->status = MBO_E_CLOSE;
427			break;
428		case -EOVERFLOW:
429			dev_warn(dev, "Babble on ep%02x\n",
430				 mdev->ep_address[channel]);
431			break;
432		}
433	}
434
435	spin_unlock_irqrestore(lock, flags);
436
437	if (likely(mbo->complete))
438		mbo->complete(mbo);
439	usb_free_urb(urb);
440}
441
442/**
443 * hdm_enqueue - receive a buffer to be used for data transfer
444 * @iface: interface to enqueue to
445 * @channel: ID of the channel
446 * @mbo: pointer to the buffer object
447 *
448 * This allocates a new URB and fills it according to the channel
449 * that is being used for transmission of data. Before the URB is
450 * submitted it is stored in the private anchor list.
451 *
452 * Returns 0 on success. On any error the URB is freed and a error code
453 * is returned.
454 *
455 * Context: Could in _some_ cases be interrupt!
456 */
457static int hdm_enqueue(struct most_interface *iface, int channel,
458		       struct mbo *mbo)
459{
460	struct most_dev *mdev = to_mdev(iface);
461	struct most_channel_config *conf;
462	int retval = 0;
463	struct urb *urb;
464	unsigned long length;
465	void *virt_address;
466
467	if (!mbo)
468		return -EINVAL;
469	if (iface->num_channels <= channel || channel < 0)
470		return -ECHRNG;
471
472	urb = usb_alloc_urb(NO_ISOCHRONOUS_URB, GFP_KERNEL);
473	if (!urb)
474		return -ENOMEM;
475
476	conf = &mdev->conf[channel];
477
478	mutex_lock(&mdev->io_mutex);
479	if (!mdev->usb_device) {
480		retval = -ENODEV;
481		goto err_free_urb;
482	}
483
484	if ((conf->direction & MOST_CH_TX) && mdev->padding_active[channel] &&
485	    hdm_add_padding(mdev, channel, mbo)) {
486		retval = -EINVAL;
487		goto err_free_urb;
488	}
489
490	urb->transfer_dma = mbo->bus_address;
491	virt_address = mbo->virt_address;
492	length = mbo->buffer_length;
493
494	if (conf->direction & MOST_CH_TX) {
495		usb_fill_bulk_urb(urb, mdev->usb_device,
496				  usb_sndbulkpipe(mdev->usb_device,
497						  mdev->ep_address[channel]),
498				  virt_address,
499				  length,
500				  hdm_write_completion,
501				  mbo);
502		if (conf->data_type != MOST_CH_ISOC &&
503		    conf->data_type != MOST_CH_SYNC)
504			urb->transfer_flags |= URB_ZERO_PACKET;
505	} else {
506		usb_fill_bulk_urb(urb, mdev->usb_device,
507				  usb_rcvbulkpipe(mdev->usb_device,
508						  mdev->ep_address[channel]),
509				  virt_address,
510				  length + conf->extra_len,
511				  hdm_read_completion,
512				  mbo);
513	}
514	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
515
516	usb_anchor_urb(urb, &mdev->busy_urbs[channel]);
517
518	retval = usb_submit_urb(urb, GFP_KERNEL);
519	if (retval) {
520		dev_err(&mdev->usb_device->dev,
521			"URB submit failed with error %d.\n", retval);
522		goto err_unanchor_urb;
523	}
524	mutex_unlock(&mdev->io_mutex);
525	return 0;
526
527err_unanchor_urb:
528	usb_unanchor_urb(urb);
529err_free_urb:
530	usb_free_urb(urb);
531	mutex_unlock(&mdev->io_mutex);
532	return retval;
533}
534
535static void *hdm_dma_alloc(struct mbo *mbo, u32 size)
536{
537	struct most_dev *mdev = to_mdev(mbo->ifp);
538
539	return usb_alloc_coherent(mdev->usb_device, size, GFP_KERNEL,
540				  &mbo->bus_address);
541}
542
543static void hdm_dma_free(struct mbo *mbo, u32 size)
544{
545	struct most_dev *mdev = to_mdev(mbo->ifp);
546
547	usb_free_coherent(mdev->usb_device, size, mbo->virt_address,
548			  mbo->bus_address);
549}
550
551/**
552 * hdm_configure_channel - receive channel configuration from core
553 * @iface: interface
554 * @channel: channel ID
555 * @conf: structure that holds the configuration information
556 *
557 * The attached network interface controller (NIC) supports a padding mode
558 * to avoid short packets on USB, hence increasing the performance due to a
559 * lower interrupt load. This mode is default for synchronous data and can
560 * be switched on for isochronous data. In case padding is active the
561 * driver needs to know the frame size of the payload in order to calculate
562 * the number of bytes it needs to pad when transmitting or to cut off when
563 * receiving data.
564 *
565 */
566static int hdm_configure_channel(struct most_interface *iface, int channel,
567				 struct most_channel_config *conf)
568{
569	unsigned int num_frames;
570	unsigned int frame_size;
571	struct most_dev *mdev = to_mdev(iface);
572	struct device *dev = &mdev->usb_device->dev;
573
574	if (!conf) {
575		dev_err(dev, "Bad config pointer.\n");
576		return -EINVAL;
577	}
578	if (channel < 0 || channel >= iface->num_channels) {
579		dev_err(dev, "Channel ID out of range.\n");
580		return -EINVAL;
581	}
582
583	mdev->is_channel_healthy[channel] = true;
584	mdev->clear_work[channel].channel = channel;
585	mdev->clear_work[channel].mdev = mdev;
586	INIT_WORK(&mdev->clear_work[channel].ws, wq_clear_halt);
587
588	if (!conf->num_buffers || !conf->buffer_size) {
589		dev_err(dev, "Misconfig: buffer size or #buffers zero.\n");
590		return -EINVAL;
591	}
592
593	if (conf->data_type != MOST_CH_SYNC &&
594	    !(conf->data_type == MOST_CH_ISOC &&
595	      conf->packets_per_xact != 0xFF)) {
596		mdev->padding_active[channel] = false;
597		/*
598		 * Since the NIC's padding mode is not going to be
599		 * used, we can skip the frame size calculations and
600		 * move directly on to exit.
601		 */
602		goto exit;
603	}
604
605	mdev->padding_active[channel] = true;
606
607	frame_size = get_stream_frame_size(&mdev->dev, conf);
608	if (frame_size == 0 || frame_size > USB_MTU) {
609		dev_warn(dev, "Misconfig: frame size wrong\n");
610		return -EINVAL;
611	}
612
613	num_frames = conf->buffer_size / frame_size;
614
615	if (conf->buffer_size % frame_size) {
616		u16 old_size = conf->buffer_size;
617
618		conf->buffer_size = num_frames * frame_size;
619		dev_warn(dev, "%s: fixed buffer size (%d -> %d)\n",
620			 mdev->suffix[channel], old_size, conf->buffer_size);
621	}
622
623	/* calculate extra length to comply w/ HW padding */
624	conf->extra_len = num_frames * (USB_MTU - frame_size);
625
626exit:
627	mdev->conf[channel] = *conf;
628	if (conf->data_type == MOST_CH_ASYNC) {
629		u16 ep = mdev->ep_address[channel];
630
631		if (start_sync_ep(mdev->usb_device, ep) < 0)
632			dev_warn(dev, "sync for ep%02x failed", ep);
633	}
634	return 0;
635}
636
637/**
638 * hdm_request_netinfo - request network information
639 * @iface: pointer to interface
640 * @channel: channel ID
641 *
642 * This is used as trigger to set up the link status timer that
643 * polls for the NI state of the INIC every 2 seconds.
644 *
645 */
646static void hdm_request_netinfo(struct most_interface *iface, int channel,
647				void (*on_netinfo)(struct most_interface *,
648						   unsigned char,
649						   unsigned char *))
650{
651	struct most_dev *mdev = to_mdev(iface);
652
653	mdev->on_netinfo = on_netinfo;
654	if (!on_netinfo)
655		return;
656
657	mdev->link_stat_timer.expires = jiffies + HZ;
658	mod_timer(&mdev->link_stat_timer, mdev->link_stat_timer.expires);
659}
660
661/**
662 * link_stat_timer_handler - schedule work obtaining mac address and link status
663 * @t: pointer to timer_list which holds a pointer to the USB device instance
664 *
665 * The handler runs in interrupt context. That's why we need to defer the
666 * tasks to a work queue.
667 */
668static void link_stat_timer_handler(struct timer_list *t)
669{
670	struct most_dev *mdev = from_timer(mdev, t, link_stat_timer);
671
672	schedule_work(&mdev->poll_work_obj);
673	mdev->link_stat_timer.expires = jiffies + (2 * HZ);
674	add_timer(&mdev->link_stat_timer);
675}
676
677/**
678 * wq_netinfo - work queue function to deliver latest networking information
679 * @wq_obj: object that holds data for our deferred work to do
680 *
681 * This retrieves the network interface status of the USB INIC
682 */
683static void wq_netinfo(struct work_struct *wq_obj)
684{
685	struct most_dev *mdev = to_mdev_from_work(wq_obj);
686	struct usb_device *usb_device = mdev->usb_device;
687	struct device *dev = &usb_device->dev;
688	u16 hi, mi, lo, link;
689	u8 hw_addr[6];
690
691	if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_HI, &hi)) {
692		dev_err(dev, "Vendor request 'hw_addr_hi' failed\n");
693		return;
694	}
695
696	if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_MI, &mi)) {
697		dev_err(dev, "Vendor request 'hw_addr_mid' failed\n");
698		return;
699	}
700
701	if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_LO, &lo)) {
702		dev_err(dev, "Vendor request 'hw_addr_low' failed\n");
703		return;
704	}
705
706	if (drci_rd_reg(usb_device, DRCI_REG_NI_STATE, &link)) {
707		dev_err(dev, "Vendor request 'link status' failed\n");
708		return;
709	}
710
711	hw_addr[0] = hi >> 8;
712	hw_addr[1] = hi;
713	hw_addr[2] = mi >> 8;
714	hw_addr[3] = mi;
715	hw_addr[4] = lo >> 8;
716	hw_addr[5] = lo;
717
718	if (mdev->on_netinfo)
719		mdev->on_netinfo(&mdev->iface, link, hw_addr);
720}
721
722/**
723 * wq_clear_halt - work queue function
724 * @wq_obj: work_struct object to execute
725 *
726 * This sends a clear_halt to the given USB pipe.
727 */
728static void wq_clear_halt(struct work_struct *wq_obj)
729{
730	struct clear_hold_work *clear_work = to_clear_hold_work(wq_obj);
731	struct most_dev *mdev = clear_work->mdev;
732	unsigned int channel = clear_work->channel;
733	int pipe = clear_work->pipe;
734	int snd_pipe;
735	int peer;
736
737	mutex_lock(&mdev->io_mutex);
738	most_stop_enqueue(&mdev->iface, channel);
739	usb_kill_anchored_urbs(&mdev->busy_urbs[channel]);
740	if (usb_clear_halt(mdev->usb_device, pipe))
741		dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
742
743	/* If the functional Stall condition has been set on an
744	 * asynchronous rx channel, we need to clear the tx channel
745	 * too, since the hardware runs its clean-up sequence on both
746	 * channels, as they are physically one on the network.
747	 *
748	 * The USB interface that exposes the asynchronous channels
749	 * contains always two endpoints, and two only.
750	 */
751	if (mdev->conf[channel].data_type == MOST_CH_ASYNC &&
752	    mdev->conf[channel].direction == MOST_CH_RX) {
753		if (channel == 0)
754			peer = 1;
755		else
756			peer = 0;
757		snd_pipe = usb_sndbulkpipe(mdev->usb_device,
758					   mdev->ep_address[peer]);
759		usb_clear_halt(mdev->usb_device, snd_pipe);
760	}
761	mdev->is_channel_healthy[channel] = true;
762	most_resume_enqueue(&mdev->iface, channel);
763	mutex_unlock(&mdev->io_mutex);
764}
765
766/*
767 * hdm_usb_fops - file operation table for USB driver
768 */
769static const struct file_operations hdm_usb_fops = {
770	.owner = THIS_MODULE,
771};
772
773/*
774 * usb_device_id - ID table for HCD device probing
775 */
776static const struct usb_device_id usbid[] = {
777	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_BRDG), },
778	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81118), },
779	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81119), },
780	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81210), },
781	{ } /* Terminating entry */
782};
783
784struct regs {
785	const char *name;
786	u16 reg;
787};
788
789static const struct regs ro_regs[] = {
790	{ "ni_state", DRCI_REG_NI_STATE },
791	{ "packet_bandwidth", DRCI_REG_PACKET_BW },
792	{ "node_address", DRCI_REG_NODE_ADDR },
793	{ "node_position", DRCI_REG_NODE_POS },
794};
795
796static const struct regs rw_regs[] = {
797	{ "mep_filter", DRCI_REG_MEP_FILTER },
798	{ "mep_hash0", DRCI_REG_HASH_TBL0 },
799	{ "mep_hash1", DRCI_REG_HASH_TBL1 },
800	{ "mep_hash2", DRCI_REG_HASH_TBL2 },
801	{ "mep_hash3", DRCI_REG_HASH_TBL3 },
802	{ "mep_eui48_hi", DRCI_REG_HW_ADDR_HI },
803	{ "mep_eui48_mi", DRCI_REG_HW_ADDR_MI },
804	{ "mep_eui48_lo", DRCI_REG_HW_ADDR_LO },
805};
806
807static int get_stat_reg_addr(const struct regs *regs, int size,
808			     const char *name, u16 *reg_addr)
809{
810	int i;
811
812	for (i = 0; i < size; i++) {
813		if (sysfs_streq(name, regs[i].name)) {
814			*reg_addr = regs[i].reg;
815			return 0;
816		}
817	}
818	return -EINVAL;
819}
820
821#define get_static_reg_addr(regs, name, reg_addr) \
822	get_stat_reg_addr(regs, ARRAY_SIZE(regs), name, reg_addr)
823
824static ssize_t value_show(struct device *dev, struct device_attribute *attr,
825			  char *buf)
826{
827	const char *name = attr->attr.name;
828	struct most_dci_obj *dci_obj = to_dci_obj(dev);
829	u16 val;
830	u16 reg_addr;
831	int err;
832
833	if (sysfs_streq(name, "arb_address"))
834		return sysfs_emit(buf, "%04x\n", dci_obj->reg_addr);
835
836	if (sysfs_streq(name, "arb_value"))
837		reg_addr = dci_obj->reg_addr;
838	else if (get_static_reg_addr(ro_regs, name, &reg_addr) &&
839		 get_static_reg_addr(rw_regs, name, &reg_addr))
840		return -EINVAL;
841
842	err = drci_rd_reg(dci_obj->usb_device, reg_addr, &val);
843	if (err < 0)
844		return err;
845
846	return sysfs_emit(buf, "%04x\n", val);
847}
848
849static ssize_t value_store(struct device *dev, struct device_attribute *attr,
850			   const char *buf, size_t count)
851{
852	u16 val;
853	u16 reg_addr;
854	const char *name = attr->attr.name;
855	struct most_dci_obj *dci_obj = to_dci_obj(dev);
856	struct usb_device *usb_dev = dci_obj->usb_device;
857	int err;
858
859	err = kstrtou16(buf, 16, &val);
860	if (err)
861		return err;
862
863	if (sysfs_streq(name, "arb_address")) {
864		dci_obj->reg_addr = val;
865		return count;
866	}
867
868	if (sysfs_streq(name, "arb_value"))
869		err = drci_wr_reg(usb_dev, dci_obj->reg_addr, val);
870	else if (sysfs_streq(name, "sync_ep"))
871		err = start_sync_ep(usb_dev, val);
872	else if (!get_static_reg_addr(rw_regs, name, &reg_addr))
873		err = drci_wr_reg(usb_dev, reg_addr, val);
874	else
875		return -EINVAL;
876
877	if (err < 0)
878		return err;
879
880	return count;
881}
882
883static DEVICE_ATTR(ni_state, 0444, value_show, NULL);
884static DEVICE_ATTR(packet_bandwidth, 0444, value_show, NULL);
885static DEVICE_ATTR(node_address, 0444, value_show, NULL);
886static DEVICE_ATTR(node_position, 0444, value_show, NULL);
887static DEVICE_ATTR(sync_ep, 0200, NULL, value_store);
888static DEVICE_ATTR(mep_filter, 0644, value_show, value_store);
889static DEVICE_ATTR(mep_hash0, 0644, value_show, value_store);
890static DEVICE_ATTR(mep_hash1, 0644, value_show, value_store);
891static DEVICE_ATTR(mep_hash2, 0644, value_show, value_store);
892static DEVICE_ATTR(mep_hash3, 0644, value_show, value_store);
893static DEVICE_ATTR(mep_eui48_hi, 0644, value_show, value_store);
894static DEVICE_ATTR(mep_eui48_mi, 0644, value_show, value_store);
895static DEVICE_ATTR(mep_eui48_lo, 0644, value_show, value_store);
896static DEVICE_ATTR(arb_address, 0644, value_show, value_store);
897static DEVICE_ATTR(arb_value, 0644, value_show, value_store);
898
899static struct attribute *dci_attrs[] = {
900	&dev_attr_ni_state.attr,
901	&dev_attr_packet_bandwidth.attr,
902	&dev_attr_node_address.attr,
903	&dev_attr_node_position.attr,
904	&dev_attr_sync_ep.attr,
905	&dev_attr_mep_filter.attr,
906	&dev_attr_mep_hash0.attr,
907	&dev_attr_mep_hash1.attr,
908	&dev_attr_mep_hash2.attr,
909	&dev_attr_mep_hash3.attr,
910	&dev_attr_mep_eui48_hi.attr,
911	&dev_attr_mep_eui48_mi.attr,
912	&dev_attr_mep_eui48_lo.attr,
913	&dev_attr_arb_address.attr,
914	&dev_attr_arb_value.attr,
915	NULL,
916};
917
918ATTRIBUTE_GROUPS(dci);
919
920static void release_dci(struct device *dev)
921{
922	struct most_dci_obj *dci = to_dci_obj(dev);
923
924	put_device(dev->parent);
925	kfree(dci);
926}
927
928static void release_mdev(struct device *dev)
929{
930	struct most_dev *mdev = to_mdev_from_dev(dev);
931
932	kfree(mdev);
933}
934/**
935 * hdm_probe - probe function of USB device driver
936 * @interface: Interface of the attached USB device
937 * @id: Pointer to the USB ID table.
938 *
939 * This allocates and initializes the device instance, adds the new
940 * entry to the internal list, scans the USB descriptors and registers
941 * the interface with the core.
942 * Additionally, the DCI objects are created and the hardware is sync'd.
943 *
944 * Return 0 on success. In case of an error a negative number is returned.
945 */
946static int
947hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
948{
949	struct usb_host_interface *usb_iface_desc = interface->cur_altsetting;
950	struct usb_device *usb_dev = interface_to_usbdev(interface);
951	struct device *dev = &usb_dev->dev;
952	struct most_dev *mdev;
953	unsigned int i;
954	unsigned int num_endpoints;
955	struct most_channel_capability *tmp_cap;
956	struct usb_endpoint_descriptor *ep_desc;
957	int ret = -ENOMEM;
958
959	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
960	if (!mdev)
961		return -ENOMEM;
962
963	usb_set_intfdata(interface, mdev);
964	num_endpoints = usb_iface_desc->desc.bNumEndpoints;
965	if (num_endpoints > MAX_NUM_ENDPOINTS) {
966		kfree(mdev);
967		return -EINVAL;
968	}
969	mutex_init(&mdev->io_mutex);
970	INIT_WORK(&mdev->poll_work_obj, wq_netinfo);
971	timer_setup(&mdev->link_stat_timer, link_stat_timer_handler, 0);
972
973	mdev->usb_device = usb_dev;
974	mdev->link_stat_timer.expires = jiffies + (2 * HZ);
975
976	mdev->iface.mod = hdm_usb_fops.owner;
977	mdev->iface.dev = &mdev->dev;
978	mdev->iface.driver_dev = &interface->dev;
979	mdev->iface.interface = ITYPE_USB;
980	mdev->iface.configure = hdm_configure_channel;
981	mdev->iface.request_netinfo = hdm_request_netinfo;
982	mdev->iface.enqueue = hdm_enqueue;
983	mdev->iface.poison_channel = hdm_poison_channel;
984	mdev->iface.dma_alloc = hdm_dma_alloc;
985	mdev->iface.dma_free = hdm_dma_free;
986	mdev->iface.description = mdev->description;
987	mdev->iface.num_channels = num_endpoints;
988
989	snprintf(mdev->description, sizeof(mdev->description),
990		 "%d-%s:%d.%d",
991		 usb_dev->bus->busnum,
992		 usb_dev->devpath,
993		 usb_dev->config->desc.bConfigurationValue,
994		 usb_iface_desc->desc.bInterfaceNumber);
995
996	mdev->dev.init_name = mdev->description;
997	mdev->dev.parent = &interface->dev;
998	mdev->dev.release = release_mdev;
999	mdev->conf = kcalloc(num_endpoints, sizeof(*mdev->conf), GFP_KERNEL);
1000	if (!mdev->conf)
1001		goto err_free_mdev;
1002
1003	mdev->cap = kcalloc(num_endpoints, sizeof(*mdev->cap), GFP_KERNEL);
1004	if (!mdev->cap)
1005		goto err_free_conf;
1006
1007	mdev->iface.channel_vector = mdev->cap;
1008	mdev->ep_address =
1009		kcalloc(num_endpoints, sizeof(*mdev->ep_address), GFP_KERNEL);
1010	if (!mdev->ep_address)
1011		goto err_free_cap;
1012
1013	mdev->busy_urbs =
1014		kcalloc(num_endpoints, sizeof(*mdev->busy_urbs), GFP_KERNEL);
1015	if (!mdev->busy_urbs)
1016		goto err_free_ep_address;
1017
1018	tmp_cap = mdev->cap;
1019	for (i = 0; i < num_endpoints; i++) {
1020		ep_desc = &usb_iface_desc->endpoint[i].desc;
1021		mdev->ep_address[i] = ep_desc->bEndpointAddress;
1022		mdev->padding_active[i] = false;
1023		mdev->is_channel_healthy[i] = true;
1024
1025		snprintf(&mdev->suffix[i][0], MAX_SUFFIX_LEN, "ep%02x",
1026			 mdev->ep_address[i]);
1027
1028		tmp_cap->name_suffix = &mdev->suffix[i][0];
1029		tmp_cap->buffer_size_packet = MAX_BUF_SIZE;
1030		tmp_cap->buffer_size_streaming = MAX_BUF_SIZE;
1031		tmp_cap->num_buffers_packet = BUF_CHAIN_SIZE;
1032		tmp_cap->num_buffers_streaming = BUF_CHAIN_SIZE;
1033		tmp_cap->data_type = MOST_CH_CONTROL | MOST_CH_ASYNC |
1034				     MOST_CH_ISOC | MOST_CH_SYNC;
1035		if (usb_endpoint_dir_in(ep_desc))
1036			tmp_cap->direction = MOST_CH_RX;
1037		else
1038			tmp_cap->direction = MOST_CH_TX;
1039		tmp_cap++;
1040		init_usb_anchor(&mdev->busy_urbs[i]);
1041		spin_lock_init(&mdev->channel_lock[i]);
1042	}
1043	dev_dbg(dev, "claimed gadget: Vendor=%4.4x ProdID=%4.4x Bus=%02x Device=%02x\n",
1044		le16_to_cpu(usb_dev->descriptor.idVendor),
1045		le16_to_cpu(usb_dev->descriptor.idProduct),
1046		usb_dev->bus->busnum,
1047		usb_dev->devnum);
1048
1049	dev_dbg(dev, "device path: /sys/bus/usb/devices/%d-%s:%d.%d\n",
1050		usb_dev->bus->busnum,
1051		usb_dev->devpath,
1052		usb_dev->config->desc.bConfigurationValue,
1053		usb_iface_desc->desc.bInterfaceNumber);
1054
1055	ret = most_register_interface(&mdev->iface);
1056	if (ret)
1057		goto err_free_busy_urbs;
1058
1059	mutex_lock(&mdev->io_mutex);
1060	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81118 ||
1061	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81119 ||
1062	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81210) {
1063		mdev->dci = kzalloc(sizeof(*mdev->dci), GFP_KERNEL);
1064		if (!mdev->dci) {
1065			mutex_unlock(&mdev->io_mutex);
1066			most_deregister_interface(&mdev->iface);
1067			ret = -ENOMEM;
1068			goto err_free_busy_urbs;
1069		}
1070
1071		mdev->dci->dev.init_name = "dci";
1072		mdev->dci->dev.parent = get_device(mdev->iface.dev);
1073		mdev->dci->dev.groups = dci_groups;
1074		mdev->dci->dev.release = release_dci;
1075		if (device_register(&mdev->dci->dev)) {
1076			mutex_unlock(&mdev->io_mutex);
1077			most_deregister_interface(&mdev->iface);
1078			ret = -ENOMEM;
1079			goto err_free_dci;
1080		}
1081		mdev->dci->usb_device = mdev->usb_device;
1082	}
1083	mutex_unlock(&mdev->io_mutex);
1084	return 0;
1085err_free_dci:
1086	put_device(&mdev->dci->dev);
1087err_free_busy_urbs:
1088	kfree(mdev->busy_urbs);
1089err_free_ep_address:
1090	kfree(mdev->ep_address);
1091err_free_cap:
1092	kfree(mdev->cap);
1093err_free_conf:
1094	kfree(mdev->conf);
1095err_free_mdev:
1096	put_device(&mdev->dev);
1097	return ret;
1098}
1099
1100/**
1101 * hdm_disconnect - disconnect function of USB device driver
1102 * @interface: Interface of the attached USB device
1103 *
1104 * This deregisters the interface with the core, removes the kernel timer
1105 * and frees resources.
1106 *
1107 * Context: hub kernel thread
1108 */
1109static void hdm_disconnect(struct usb_interface *interface)
1110{
1111	struct most_dev *mdev = usb_get_intfdata(interface);
1112
1113	mutex_lock(&mdev->io_mutex);
1114	usb_set_intfdata(interface, NULL);
1115	mdev->usb_device = NULL;
1116	mutex_unlock(&mdev->io_mutex);
1117
1118	del_timer_sync(&mdev->link_stat_timer);
1119	cancel_work_sync(&mdev->poll_work_obj);
1120
1121	if (mdev->dci)
1122		device_unregister(&mdev->dci->dev);
1123	most_deregister_interface(&mdev->iface);
1124
1125	kfree(mdev->busy_urbs);
1126	kfree(mdev->cap);
1127	kfree(mdev->conf);
1128	kfree(mdev->ep_address);
1129	put_device(&mdev->dci->dev);
1130	put_device(&mdev->dev);
1131}
1132
1133static int hdm_suspend(struct usb_interface *interface, pm_message_t message)
1134{
1135	struct most_dev *mdev = usb_get_intfdata(interface);
1136	int i;
1137
1138	mutex_lock(&mdev->io_mutex);
1139	for (i = 0; i < mdev->iface.num_channels; i++) {
1140		most_stop_enqueue(&mdev->iface, i);
1141		usb_kill_anchored_urbs(&mdev->busy_urbs[i]);
1142	}
1143	mutex_unlock(&mdev->io_mutex);
1144	return 0;
1145}
1146
1147static int hdm_resume(struct usb_interface *interface)
1148{
1149	struct most_dev *mdev = usb_get_intfdata(interface);
1150	int i;
1151
1152	mutex_lock(&mdev->io_mutex);
1153	for (i = 0; i < mdev->iface.num_channels; i++)
1154		most_resume_enqueue(&mdev->iface, i);
1155	mutex_unlock(&mdev->io_mutex);
1156	return 0;
1157}
1158
1159static struct usb_driver hdm_usb = {
1160	.name = "hdm_usb",
1161	.id_table = usbid,
1162	.probe = hdm_probe,
1163	.disconnect = hdm_disconnect,
1164	.resume = hdm_resume,
1165	.suspend = hdm_suspend,
1166};
1167
1168module_usb_driver(hdm_usb);
1169MODULE_LICENSE("GPL");
1170MODULE_AUTHOR("Christian Gromm <christian.gromm@microchip.com>");
1171MODULE_DESCRIPTION("HDM_4_USB");
1172