[linux-2.6-block.git] / drivers / ieee1394 / iso.c

/*
 * IEEE 1394 for Linux
 *
 * kernel ISO transmission/reception
 *
 * Copyright (C) 2002 Maas Digital LLC
 *
 * This code is licensed under the GPL.  See the file COPYING in the root
 * directory of the kernel sources for details.
 */

#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/slab.h>

#include "hosts.h"
#include "iso.h"

/**
 * hpsb_iso_stop - stop DMA
 */
void hpsb_iso_stop(struct hpsb_iso *iso)
{
	if (!(iso->flags & HPSB_ISO_DRIVER_STARTED))
		return;

	iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
				  XMIT_STOP : RECV_STOP, 0);
	iso->flags &= ~HPSB_ISO_DRIVER_STARTED;
}

/**
 * hpsb_iso_shutdown - deallocate buffer and DMA context
 */
void hpsb_iso_shutdown(struct hpsb_iso *iso)
{
	if (iso->flags & HPSB_ISO_DRIVER_INIT) {
		hpsb_iso_stop(iso);
		iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
					  XMIT_SHUTDOWN : RECV_SHUTDOWN, 0);
		iso->flags &= ~HPSB_ISO_DRIVER_INIT;
	}

	dma_region_free(&iso->data_buf);
	kfree(iso);
}

static struct hpsb_iso *hpsb_iso_common_init(struct hpsb_host *host,
					     enum hpsb_iso_type type,
					     unsigned int data_buf_size,
					     unsigned int buf_packets,
					     int channel, int dma_mode,
					     int irq_interval,
					     void (*callback) (struct hpsb_iso
							       *))
{
	struct hpsb_iso *iso;
	int dma_direction;

	/* make sure driver supports the ISO API */
	if (!host->driver->isoctl) {
		printk(KERN_INFO
		       "ieee1394: host driver '%s' does not support the rawiso API\n",
		       host->driver->name);
		return NULL;
	}

	/* sanitize parameters */

	if (buf_packets < 2)
		buf_packets = 2;

	if ((dma_mode < HPSB_ISO_DMA_DEFAULT)
	    || (dma_mode > HPSB_ISO_DMA_PACKET_PER_BUFFER))
		dma_mode = HPSB_ISO_DMA_DEFAULT;

	if ((irq_interval < 0) || (irq_interval > buf_packets / 4))
		irq_interval = buf_packets / 4;
	if (irq_interval == 0)	/* really interrupt for each packet */
		irq_interval = 1;

	if (channel < -1 || channel >= 64)
		return NULL;

	/* channel = -1 is OK for multi-channel recv but not for xmit */
	if (type == HPSB_ISO_XMIT && channel < 0)
		return NULL;

	/* allocate and write the struct hpsb_iso */

	iso =
	    kmalloc(sizeof(*iso) +
		    buf_packets * sizeof(struct hpsb_iso_packet_info),
		    GFP_KERNEL);
	if (!iso)
		return NULL;

	iso->infos = (struct hpsb_iso_packet_info *)(iso + 1);

	iso->type = type;
	iso->host = host;
	iso->hostdata = NULL;
	iso->callback = callback;
	init_waitqueue_head(&iso->waitq);
	iso->channel = channel;
	iso->irq_interval = irq_interval;
	iso->dma_mode = dma_mode;
	dma_region_init(&iso->data_buf);
	iso->buf_size = PAGE_ALIGN(data_buf_size);
	iso->buf_packets = buf_packets;
	iso->pkt_dma = 0;
	iso->first_packet = 0;
	spin_lock_init(&iso->lock);

	if (iso->type == HPSB_ISO_XMIT) {
		iso->n_ready_packets = iso->buf_packets;
		dma_direction = PCI_DMA_TODEVICE;
	} else {
		iso->n_ready_packets = 0;
		dma_direction = PCI_DMA_FROMDEVICE;
	}

	atomic_set(&iso->overflows, 0);
	iso->bytes_discarded = 0;
	iso->flags = 0;
	iso->prebuffer = 0;

	/* allocate the packet buffer */
	if (dma_region_alloc
	    (&iso->data_buf, iso->buf_size, host->pdev, dma_direction))
		goto err;

	return iso;

      err:
	hpsb_iso_shutdown(iso);
	return NULL;
}

/**
 * hpsb_iso_n_ready - returns number of packets ready to send or receive
 */
int hpsb_iso_n_ready(struct hpsb_iso *iso)
{
	unsigned long flags;
	int val;

	spin_lock_irqsave(&iso->lock, flags);
	val = iso->n_ready_packets;
	spin_unlock_irqrestore(&iso->lock, flags);

	return val;
}

/**
 * hpsb_iso_xmit_init - allocate the buffer and DMA context
 */
struct hpsb_iso *hpsb_iso_xmit_init(struct hpsb_host *host,
				    unsigned int data_buf_size,
				    unsigned int buf_packets,
				    int channel,
				    int speed,
				    int irq_interval,
				    void (*callback) (struct hpsb_iso *))
{
	struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_XMIT,
						    data_buf_size, buf_packets,
						    channel,
						    HPSB_ISO_DMA_DEFAULT,
						    irq_interval, callback);
	if (!iso)
		return NULL;

	iso->speed = speed;

	/* tell the driver to start working */
	if (host->driver->isoctl(iso, XMIT_INIT, 0))
		goto err;

	iso->flags |= HPSB_ISO_DRIVER_INIT;
	return iso;

      err:
	hpsb_iso_shutdown(iso);
	return NULL;
}

/**
 * hpsb_iso_recv_init - allocate the buffer and DMA context
 *
 * Note, if channel = -1, multi-channel receive is enabled.
 */
struct hpsb_iso *hpsb_iso_recv_init(struct hpsb_host *host,
				    unsigned int data_buf_size,
				    unsigned int buf_packets,
				    int channel,
				    int dma_mode,
				    int irq_interval,
				    void (*callback) (struct hpsb_iso *))
{
	struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_RECV,
						    data_buf_size, buf_packets,
						    channel, dma_mode,
						    irq_interval, callback);
	if (!iso)
		return NULL;

	/* tell the driver to start working */
	if (host->driver->isoctl(iso, RECV_INIT, 0))
		goto err;

	iso->flags |= HPSB_ISO_DRIVER_INIT;
	return iso;

      err:
	hpsb_iso_shutdown(iso);
	return NULL;
}

/**
 * hpsb_iso_recv_listen_channel
 *
 * multi-channel only
 */
int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel)
{
	if (iso->type != HPSB_ISO_RECV || iso->channel != -1 || channel >= 64)
		return -EINVAL;
	return iso->host->driver->isoctl(iso, RECV_LISTEN_CHANNEL, channel);
}

/**
 * hpsb_iso_recv_unlisten_channel
 *
 * multi-channel only
 */
int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel)
{
	if (iso->type != HPSB_ISO_RECV || iso->channel != -1 || channel >= 64)
		return -EINVAL;
	return iso->host->driver->isoctl(iso, RECV_UNLISTEN_CHANNEL, channel);
}

/**
 * hpsb_iso_recv_set_channel_mask
 *
 * multi-channel only
 */
int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask)
{
	if (iso->type != HPSB_ISO_RECV || iso->channel != -1)
		return -EINVAL;
	return iso->host->driver->isoctl(iso, RECV_SET_CHANNEL_MASK,
					 (unsigned long)&mask);
}

/**
 * hpsb_iso_recv_flush - check for arrival of new packets
 *
 * check for arrival of new packets immediately (even if irq_interval
 * has not yet been reached)
 */
int hpsb_iso_recv_flush(struct hpsb_iso *iso)
{
	if (iso->type != HPSB_ISO_RECV)
		return -EINVAL;
	return iso->host->driver->isoctl(iso, RECV_FLUSH, 0);
}

static int do_iso_xmit_start(struct hpsb_iso *iso, int cycle)
{
	int retval = iso->host->driver->isoctl(iso, XMIT_START, cycle);
	if (retval)
		return retval;

	iso->flags |= HPSB_ISO_DRIVER_STARTED;
	return retval;
}

/**
 * hpsb_iso_xmit_start - start DMA
 */
int hpsb_iso_xmit_start(struct hpsb_iso *iso, int cycle, int prebuffer)
{
	if (iso->type != HPSB_ISO_XMIT)
		return -1;

	if (iso->flags & HPSB_ISO_DRIVER_STARTED)
		return 0;

	if (cycle < -1)
		cycle = -1;
	else if (cycle >= 8000)
		cycle %= 8000;

	iso->xmit_cycle = cycle;

	if (prebuffer < 0)
		prebuffer = iso->buf_packets - 1;
	else if (prebuffer == 0)
		prebuffer = 1;

	if (prebuffer >= iso->buf_packets)
		prebuffer = iso->buf_packets - 1;

	iso->prebuffer = prebuffer;

	/* remember the starting cycle; DMA will commence from xmit_queue_packets()
	   once enough packets have been buffered */
	iso->start_cycle = cycle;

	return 0;
}

/**
 * hpsb_iso_recv_start - start DMA
 */
int hpsb_iso_recv_start(struct hpsb_iso *iso, int cycle, int tag_mask, int sync)
{
	int retval = 0;
	int isoctl_args[3];

	if (iso->type != HPSB_ISO_RECV)
		return -1;

	if (iso->flags & HPSB_ISO_DRIVER_STARTED)
		return 0;

	if (cycle < -1)
		cycle = -1;
	else if (cycle >= 8000)
		cycle %= 8000;

	isoctl_args[0] = cycle;

	if (tag_mask < 0)
		/* match all tags */
		tag_mask = 0xF;
	isoctl_args[1] = tag_mask;

	isoctl_args[2] = sync;

	retval =
	    iso->host->driver->isoctl(iso, RECV_START,
				      (unsigned long)&isoctl_args[0]);
	if (retval)
		return retval;

	iso->flags |= HPSB_ISO_DRIVER_STARTED;
	return retval;
}

/* check to make sure the user has not supplied bogus values of offset/len
 * that would cause the kernel to access memory outside the buffer */
static int hpsb_iso_check_offset_len(struct hpsb_iso *iso,
				     unsigned int offset, unsigned short len,
				     unsigned int *out_offset,
				     unsigned short *out_len)
{
	if (offset >= iso->buf_size)
		return -EFAULT;

	/* make sure the packet does not go beyond the end of the buffer */
	if (offset + len > iso->buf_size)
		return -EFAULT;

	/* check for wrap-around */
	if (offset + len < offset)
		return -EFAULT;

	/* now we can trust 'offset' and 'length' */
	*out_offset = offset;
	*out_len = len;

	return 0;
}

/**
 * hpsb_iso_xmit_queue_packet - queue a packet for transmission.
 *
 * @offset is relative to the beginning of the DMA buffer, where the packet's
 * data payload should already have been placed.
 */
int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len,
			       u8 tag, u8 sy)
{
	struct hpsb_iso_packet_info *info;
	unsigned long flags;
	int rv;

	if (iso->type != HPSB_ISO_XMIT)
		return -EINVAL;

	/* is there space in the buffer? */
	if (iso->n_ready_packets <= 0) {
		return -EBUSY;
	}

	info = &iso->infos[iso->first_packet];

	/* check for bogus offset/length */
	if (hpsb_iso_check_offset_len
	    (iso, offset, len, &info->offset, &info->len))
		return -EFAULT;

	info->tag = tag;
	info->sy = sy;

	spin_lock_irqsave(&iso->lock, flags);

	rv = iso->host->driver->isoctl(iso, XMIT_QUEUE, (unsigned long)info);
	if (rv)
		goto out;

	/* increment cursors */
	iso->first_packet = (iso->first_packet + 1) % iso->buf_packets;
	iso->xmit_cycle = (iso->xmit_cycle + 1) % 8000;
	iso->n_ready_packets--;

	if (iso->prebuffer != 0) {
		iso->prebuffer--;
		if (iso->prebuffer <= 0) {
			iso->prebuffer = 0;
			rv = do_iso_xmit_start(iso, iso->start_cycle);
		}
	}

      out:
	spin_unlock_irqrestore(&iso->lock, flags);
	return rv;
}

/**
 * hpsb_iso_xmit_sync - wait until all queued packets have been transmitted
 */
int hpsb_iso_xmit_sync(struct hpsb_iso *iso)
{
	if (iso->type != HPSB_ISO_XMIT)
		return -EINVAL;

	return wait_event_interruptible(iso->waitq,
					hpsb_iso_n_ready(iso) ==
					iso->buf_packets);
}

/**
 * hpsb_iso_packet_sent
 *
 * Available to low-level drivers.
 *
 * Call after a packet has been transmitted to the bus (interrupt context is
 * OK).  @cycle is the _exact_ cycle the packet was sent on.  @error should be
 * non-zero if some sort of error occurred when sending the packet.
 */
void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error)
{
	unsigned long flags;
	spin_lock_irqsave(&iso->lock, flags);

	/* predict the cycle of the next packet to be queued */

	/* jump ahead by the number of packets that are already buffered */
	cycle += iso->buf_packets - iso->n_ready_packets;
	cycle %= 8000;

	iso->xmit_cycle = cycle;
	iso->n_ready_packets++;
	iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;

	if (iso->n_ready_packets == iso->buf_packets || error != 0) {
		/* the buffer has run empty! */
		atomic_inc(&iso->overflows);
	}

	spin_unlock_irqrestore(&iso->lock, flags);
}

/**
 * hpsb_iso_packet_received
 *
 * Available to low-level drivers.
 *
 * Call after a packet has been received (interrupt context is OK).
 */
void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
			      u16 total_len, u16 cycle, u8 channel, u8 tag,
			      u8 sy)
{
	unsigned long flags;
	spin_lock_irqsave(&iso->lock, flags);

	if (iso->n_ready_packets == iso->buf_packets) {
		/* overflow! */
		atomic_inc(&iso->overflows);
		/* Record size of this discarded packet */
		iso->bytes_discarded += total_len;
	} else {
		struct hpsb_iso_packet_info *info = &iso->infos[iso->pkt_dma];
		info->offset = offset;
		info->len = len;
		info->total_len = total_len;
		info->cycle = cycle;
		info->channel = channel;
		info->tag = tag;
		info->sy = sy;

		iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;
		iso->n_ready_packets++;
	}

	spin_unlock_irqrestore(&iso->lock, flags);
}

/**
 * hpsb_iso_recv_release_packets - release packets, reuse buffer
 *
 * @n_packets have been read out of the buffer, re-use the buffer space
 */
int hpsb_iso_recv_release_packets(struct hpsb_iso *iso, unsigned int n_packets)
{
	unsigned long flags;
	unsigned int i;
	int rv = 0;

	if (iso->type != HPSB_ISO_RECV)
		return -1;

	spin_lock_irqsave(&iso->lock, flags);
	for (i = 0; i < n_packets; i++) {
		rv = iso->host->driver->isoctl(iso, RECV_RELEASE,
					       (unsigned long)&iso->infos[iso->
									  first_packet]);
		if (rv)
			break;

		iso->first_packet = (iso->first_packet + 1) % iso->buf_packets;
		iso->n_ready_packets--;

		/* release memory from packets discarded when queue was full  */
		if (iso->n_ready_packets == 0) {	/* Release only after all prior packets handled */
			if (iso->bytes_discarded != 0) {
				struct hpsb_iso_packet_info inf;
				inf.total_len = iso->bytes_discarded;
				iso->host->driver->isoctl(iso, RECV_RELEASE,
							  (unsigned long)&inf);
				iso->bytes_discarded = 0;
			}
		}
	}
	spin_unlock_irqrestore(&iso->lock, flags);
	return rv;
}

/**
 * hpsb_iso_wake
 *
 * Available to low-level drivers.
 *
 * Call to wake waiting processes after buffer space has opened up.
 */
void hpsb_iso_wake(struct hpsb_iso *iso)
{
	wake_up_interruptible(&iso->waitq);

	if (iso->callback)
		iso->callback(iso);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* IEEE 1394 for Linux
	3	*
	4	* kernel ISO transmission/reception
	5	*
	6	* Copyright (C) 2002 Maas Digital LLC
	7	*
	8	* This code is licensed under the GPL. See the file COPYING in the root
	9	* directory of the kernel sources for details.
	10	*/
	11
de4394f1	12	#include <linux/pci.h>
b9e5eb06	13	#include <linux/sched.h>
de4394f1 SR	14	#include <linux/slab.h>
	15
	16	#include "hosts.h"
1da177e4 LT	17	#include "iso.h"
1da177e4 LT	18
afd6546d SR	19	/**
	20	* hpsb_iso_stop - stop DMA
	21	*/
1da177e4 LT	22	void hpsb_iso_stop(struct hpsb_iso *iso)
	23	{
	24	if (!(iso->flags & HPSB_ISO_DRIVER_STARTED))
	25	return;
	26
	27	iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
	28	XMIT_STOP : RECV_STOP, 0);
	29	iso->flags &= ~HPSB_ISO_DRIVER_STARTED;
	30	}
	31
afd6546d SR	32	/**
	33	* hpsb_iso_shutdown - deallocate buffer and DMA context
	34	*/
1da177e4 LT	35	void hpsb_iso_shutdown(struct hpsb_iso *iso)
	36	{
	37	if (iso->flags & HPSB_ISO_DRIVER_INIT) {
	38	hpsb_iso_stop(iso);
	39	iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?
	40	XMIT_SHUTDOWN : RECV_SHUTDOWN, 0);
	41	iso->flags &= ~HPSB_ISO_DRIVER_INIT;
	42	}
	43
	44	dma_region_free(&iso->data_buf);
	45	kfree(iso);
	46	}
	47
066ef9c2 JMH	48	static struct hpsb_iso hpsb_iso_common_init(struct hpsb_host host,
066ef9c2 JMH	49	enum hpsb_iso_type type,
1da177e4 LT	50	unsigned int data_buf_size,
1da177e4 LT	51	unsigned int buf_packets,
066ef9c2	52	int channel, int dma_mode,
1da177e4	53	int irq_interval,
066ef9c2 JMH	54	void (*callback) (struct hpsb_iso
066ef9c2 JMH	55	*))
1da177e4 LT	56	{
	57	struct hpsb_iso *iso;
	58	int dma_direction;
	59
	60	/* make sure driver supports the ISO API */
	61	if (!host->driver->isoctl) {
066ef9c2 JMH	62	printk(KERN_INFO
066ef9c2 JMH	63	"ieee1394: host driver '%s' does not support the rawiso API\n",
1da177e4 LT	64	host->driver->name);
	65	return NULL;
	66	}
	67
	68	/* sanitize parameters */
	69
	70	if (buf_packets < 2)
	71	buf_packets = 2;
	72
066ef9c2 JMH	73	if ((dma_mode < HPSB_ISO_DMA_DEFAULT)
	74	\|\| (dma_mode > HPSB_ISO_DMA_PACKET_PER_BUFFER))
	75	dma_mode = HPSB_ISO_DMA_DEFAULT;
1da177e4	76
1934b8b6	77	if ((irq_interval < 0) \|\| (irq_interval > buf_packets / 4))
066ef9c2 JMH	78	irq_interval = buf_packets / 4;
066ef9c2 JMH	79	if (irq_interval == 0) /* really interrupt for each packet */
1da177e4	80	irq_interval = 1;
1da177e4 LT	81
	82	if (channel < -1 \|\| channel >= 64)
	83	return NULL;
	84
	85	/* channel = -1 is OK for multi-channel recv but not for xmit */
	86	if (type == HPSB_ISO_XMIT && channel < 0)
	87	return NULL;
	88
	89	/* allocate and write the struct hpsb_iso */
	90
066ef9c2 JMH	91	iso =
	92	kmalloc(sizeof(*iso) +
	93	buf_packets * sizeof(struct hpsb_iso_packet_info),
	94	GFP_KERNEL);
1da177e4 LT	95	if (!iso)
	96	return NULL;
	97
	98	iso->infos = (struct hpsb_iso_packet_info *)(iso + 1);
	99
	100	iso->type = type;
	101	iso->host = host;
	102	iso->hostdata = NULL;
	103	iso->callback = callback;
	104	init_waitqueue_head(&iso->waitq);
	105	iso->channel = channel;
	106	iso->irq_interval = irq_interval;
	107	iso->dma_mode = dma_mode;
	108	dma_region_init(&iso->data_buf);
	109	iso->buf_size = PAGE_ALIGN(data_buf_size);
	110	iso->buf_packets = buf_packets;
	111	iso->pkt_dma = 0;
	112	iso->first_packet = 0;
	113	spin_lock_init(&iso->lock);
	114
	115	if (iso->type == HPSB_ISO_XMIT) {
	116	iso->n_ready_packets = iso->buf_packets;
	117	dma_direction = PCI_DMA_TODEVICE;
	118	} else {
	119	iso->n_ready_packets = 0;
	120	dma_direction = PCI_DMA_FROMDEVICE;
	121	}
	122
	123	atomic_set(&iso->overflows, 0);
1934b8b6	124	iso->bytes_discarded = 0;
1da177e4 LT	125	iso->flags = 0;
	126	iso->prebuffer = 0;
	127
	128	/* allocate the packet buffer */
066ef9c2 JMH	129	if (dma_region_alloc
066ef9c2 JMH	130	(&iso->data_buf, iso->buf_size, host->pdev, dma_direction))
1da177e4 LT	131	goto err;
	132
	133	return iso;
	134
066ef9c2	135	err:
1da177e4 LT	136	hpsb_iso_shutdown(iso);
	137	return NULL;
	138	}
	139
afd6546d SR	140	/**
	141	* hpsb_iso_n_ready - returns number of packets ready to send or receive
	142	*/
066ef9c2	143	int hpsb_iso_n_ready(struct hpsb_iso *iso)
1da177e4 LT	144	{
	145	unsigned long flags;
	146	int val;
	147
	148	spin_lock_irqsave(&iso->lock, flags);
	149	val = iso->n_ready_packets;
	150	spin_unlock_irqrestore(&iso->lock, flags);
	151
	152	return val;
	153	}
	154
afd6546d SR	155	/**
	156	* hpsb_iso_xmit_init - allocate the buffer and DMA context
	157	*/
066ef9c2	158	struct hpsb_iso hpsb_iso_xmit_init(struct hpsb_host host,
1da177e4 LT	159	unsigned int data_buf_size,
	160	unsigned int buf_packets,
	161	int channel,
	162	int speed,
	163	int irq_interval,
066ef9c2	164	void (callback) (struct hpsb_iso ))
1da177e4 LT	165	{
	166	struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_XMIT,
	167	data_buf_size, buf_packets,
066ef9c2 JMH	168	channel,
	169	HPSB_ISO_DMA_DEFAULT,
	170	irq_interval, callback);
1da177e4 LT	171	if (!iso)
	172	return NULL;
	173
	174	iso->speed = speed;
	175
	176	/* tell the driver to start working */
	177	if (host->driver->isoctl(iso, XMIT_INIT, 0))
	178	goto err;
	179
	180	iso->flags \|= HPSB_ISO_DRIVER_INIT;
	181	return iso;
	182
066ef9c2	183	err:
1da177e4 LT	184	hpsb_iso_shutdown(iso);
	185	return NULL;
	186	}
	187
afd6546d SR	188	/**
	189	* hpsb_iso_recv_init - allocate the buffer and DMA context
	190	*
	191	* Note, if channel = -1, multi-channel receive is enabled.
	192	*/
066ef9c2	193	struct hpsb_iso hpsb_iso_recv_init(struct hpsb_host host,
1da177e4 LT	194	unsigned int data_buf_size,
	195	unsigned int buf_packets,
	196	int channel,
	197	int dma_mode,
	198	int irq_interval,
066ef9c2	199	void (callback) (struct hpsb_iso ))
1da177e4 LT	200	{
	201	struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_RECV,
	202	data_buf_size, buf_packets,
066ef9c2 JMH	203	channel, dma_mode,
066ef9c2 JMH	204	irq_interval, callback);
1da177e4 LT	205	if (!iso)
	206	return NULL;
	207
	208	/* tell the driver to start working */
	209	if (host->driver->isoctl(iso, RECV_INIT, 0))
	210	goto err;
	211
	212	iso->flags \|= HPSB_ISO_DRIVER_INIT;
	213	return iso;
	214
066ef9c2	215	err:
1da177e4 LT	216	hpsb_iso_shutdown(iso);
	217	return NULL;
	218	}
	219
afd6546d SR	220	/**
	221	* hpsb_iso_recv_listen_channel
	222	*
	223	* multi-channel only
	224	*/
1da177e4 LT	225	int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel)
	226	{
	227	if (iso->type != HPSB_ISO_RECV \|\| iso->channel != -1 \|\| channel >= 64)
	228	return -EINVAL;
	229	return iso->host->driver->isoctl(iso, RECV_LISTEN_CHANNEL, channel);
	230	}
	231
afd6546d SR	232	/**
	233	* hpsb_iso_recv_unlisten_channel
	234	*
	235	* multi-channel only
	236	*/
1da177e4 LT	237	int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel)
1da177e4 LT	238	{
066ef9c2 JMH	239	if (iso->type != HPSB_ISO_RECV \|\| iso->channel != -1 \|\| channel >= 64)
	240	return -EINVAL;
	241	return iso->host->driver->isoctl(iso, RECV_UNLISTEN_CHANNEL, channel);
1da177e4 LT	242	}
1da177e4 LT	243
afd6546d SR	244	/**
	245	* hpsb_iso_recv_set_channel_mask
	246	*
	247	* multi-channel only
	248	*/
1da177e4 LT	249	int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask)
	250	{
	251	if (iso->type != HPSB_ISO_RECV \|\| iso->channel != -1)
	252	return -EINVAL;
066ef9c2 JMH	253	return iso->host->driver->isoctl(iso, RECV_SET_CHANNEL_MASK,
066ef9c2 JMH	254	(unsigned long)&mask);
1da177e4 LT	255	}
1da177e4 LT	256
afd6546d SR	257	/**
	258	* hpsb_iso_recv_flush - check for arrival of new packets
	259	*
	260	* check for arrival of new packets immediately (even if irq_interval
	261	* has not yet been reached)
	262	*/
1da177e4 LT	263	int hpsb_iso_recv_flush(struct hpsb_iso *iso)
	264	{
	265	if (iso->type != HPSB_ISO_RECV)
	266	return -EINVAL;
	267	return iso->host->driver->isoctl(iso, RECV_FLUSH, 0);
	268	}
	269
	270	static int do_iso_xmit_start(struct hpsb_iso *iso, int cycle)
	271	{
	272	int retval = iso->host->driver->isoctl(iso, XMIT_START, cycle);
	273	if (retval)
	274	return retval;
	275
	276	iso->flags \|= HPSB_ISO_DRIVER_STARTED;
	277	return retval;
	278	}
	279
afd6546d SR	280	/**
	281	* hpsb_iso_xmit_start - start DMA
	282	*/
1da177e4 LT	283	int hpsb_iso_xmit_start(struct hpsb_iso *iso, int cycle, int prebuffer)
	284	{
	285	if (iso->type != HPSB_ISO_XMIT)
	286	return -1;
	287
	288	if (iso->flags & HPSB_ISO_DRIVER_STARTED)
	289	return 0;
	290
	291	if (cycle < -1)
	292	cycle = -1;
	293	else if (cycle >= 8000)
	294	cycle %= 8000;
	295
	296	iso->xmit_cycle = cycle;
	297
	298	if (prebuffer < 0)
1934b8b6	299	prebuffer = iso->buf_packets - 1;
1da177e4 LT	300	else if (prebuffer == 0)
	301	prebuffer = 1;
	302
1934b8b6 BC	303	if (prebuffer >= iso->buf_packets)
1934b8b6 BC	304	prebuffer = iso->buf_packets - 1;
1da177e4 LT	305
	306	iso->prebuffer = prebuffer;
	307
	308	/* remember the starting cycle; DMA will commence from xmit_queue_packets()
	309	once enough packets have been buffered */
	310	iso->start_cycle = cycle;
	311
	312	return 0;
	313	}
	314
afd6546d SR	315	/**
	316	* hpsb_iso_recv_start - start DMA
	317	*/
1da177e4 LT	318	int hpsb_iso_recv_start(struct hpsb_iso *iso, int cycle, int tag_mask, int sync)
	319	{
	320	int retval = 0;
	321	int isoctl_args[3];
	322
	323	if (iso->type != HPSB_ISO_RECV)
	324	return -1;
	325
	326	if (iso->flags & HPSB_ISO_DRIVER_STARTED)
	327	return 0;
	328
	329	if (cycle < -1)
	330	cycle = -1;
	331	else if (cycle >= 8000)
	332	cycle %= 8000;
	333
	334	isoctl_args[0] = cycle;
	335
	336	if (tag_mask < 0)
	337	/* match all tags */
	338	tag_mask = 0xF;
	339	isoctl_args[1] = tag_mask;
	340
	341	isoctl_args[2] = sync;
	342
066ef9c2 JMH	343	retval =
	344	iso->host->driver->isoctl(iso, RECV_START,
	345	(unsigned long)&isoctl_args[0]);
1da177e4 LT	346	if (retval)
	347	return retval;
	348
	349	iso->flags \|= HPSB_ISO_DRIVER_STARTED;
	350	return retval;
	351	}
	352
	353	/* check to make sure the user has not supplied bogus values of offset/len
afd6546d	354	* that would cause the kernel to access memory outside the buffer */
1da177e4 LT	355	static int hpsb_iso_check_offset_len(struct hpsb_iso *iso,
1da177e4 LT	356	unsigned int offset, unsigned short len,
066ef9c2 JMH	357	unsigned int *out_offset,
066ef9c2 JMH	358	unsigned short *out_len)
1da177e4 LT	359	{
	360	if (offset >= iso->buf_size)
	361	return -EFAULT;
	362
	363	/* make sure the packet does not go beyond the end of the buffer */
	364	if (offset + len > iso->buf_size)
	365	return -EFAULT;
	366
	367	/* check for wrap-around */
	368	if (offset + len < offset)
	369	return -EFAULT;
	370
	371	/* now we can trust 'offset' and 'length' */
	372	*out_offset = offset;
	373	*out_len = len;
	374
	375	return 0;
	376	}
	377
afd6546d SR	378	/**
	379	* hpsb_iso_xmit_queue_packet - queue a packet for transmission.
	380	*
	381	* @offset is relative to the beginning of the DMA buffer, where the packet's
	382	* data payload should already have been placed.
	383	*/
066ef9c2 JMH	384	int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len,
066ef9c2 JMH	385	u8 tag, u8 sy)
1da177e4 LT	386	{
	387	struct hpsb_iso_packet_info *info;
	388	unsigned long flags;
	389	int rv;
	390
	391	if (iso->type != HPSB_ISO_XMIT)
	392	return -EINVAL;
	393
	394	/* is there space in the buffer? */
	395	if (iso->n_ready_packets <= 0) {
	396	return -EBUSY;
	397	}
	398
	399	info = &iso->infos[iso->first_packet];
	400
	401	/* check for bogus offset/length */
066ef9c2 JMH	402	if (hpsb_iso_check_offset_len
066ef9c2 JMH	403	(iso, offset, len, &info->offset, &info->len))
1da177e4 LT	404	return -EFAULT;
	405
	406	info->tag = tag;
	407	info->sy = sy;
	408
	409	spin_lock_irqsave(&iso->lock, flags);
	410
066ef9c2	411	rv = iso->host->driver->isoctl(iso, XMIT_QUEUE, (unsigned long)info);
1da177e4 LT	412	if (rv)
	413	goto out;
	414
	415	/* increment cursors */
066ef9c2 JMH	416	iso->first_packet = (iso->first_packet + 1) % iso->buf_packets;
066ef9c2 JMH	417	iso->xmit_cycle = (iso->xmit_cycle + 1) % 8000;
1da177e4 LT	418	iso->n_ready_packets--;
	419
	420	if (iso->prebuffer != 0) {
	421	iso->prebuffer--;
	422	if (iso->prebuffer <= 0) {
	423	iso->prebuffer = 0;
	424	rv = do_iso_xmit_start(iso, iso->start_cycle);
	425	}
	426	}
	427
066ef9c2	428	out:
1da177e4 LT	429	spin_unlock_irqrestore(&iso->lock, flags);
	430	return rv;
	431	}
	432
afd6546d SR	433	/**
	434	* hpsb_iso_xmit_sync - wait until all queued packets have been transmitted
	435	*/
1da177e4 LT	436	int hpsb_iso_xmit_sync(struct hpsb_iso *iso)
	437	{
	438	if (iso->type != HPSB_ISO_XMIT)
	439	return -EINVAL;
	440
066ef9c2 JMH	441	return wait_event_interruptible(iso->waitq,
	442	hpsb_iso_n_ready(iso) ==
	443	iso->buf_packets);
1da177e4 LT	444	}
1da177e4 LT	445
afd6546d SR	446	/**
	447	* hpsb_iso_packet_sent
	448	*
	449	* Available to low-level drivers.
	450	*
	451	* Call after a packet has been transmitted to the bus (interrupt context is
	452	* OK). @cycle is the _exact_ cycle the packet was sent on. @error should be
	453	* non-zero if some sort of error occurred when sending the packet.
	454	*/
1da177e4 LT	455	void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error)
	456	{
	457	unsigned long flags;
	458	spin_lock_irqsave(&iso->lock, flags);
	459
	460	/* predict the cycle of the next packet to be queued */
	461
	462	/* jump ahead by the number of packets that are already buffered */
	463	cycle += iso->buf_packets - iso->n_ready_packets;
	464	cycle %= 8000;
	465
	466	iso->xmit_cycle = cycle;
	467	iso->n_ready_packets++;
	468	iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;
	469
	470	if (iso->n_ready_packets == iso->buf_packets \|\| error != 0) {
	471	/* the buffer has run empty! */
	472	atomic_inc(&iso->overflows);
	473	}
	474
	475	spin_unlock_irqrestore(&iso->lock, flags);
	476	}
	477
afd6546d SR	478	/**
	479	* hpsb_iso_packet_received
	480	*
	481	* Available to low-level drivers.
	482	*
	483	* Call after a packet has been received (interrupt context is OK).
	484	*/
1da177e4	485	void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,
066ef9c2 JMH	486	u16 total_len, u16 cycle, u8 channel, u8 tag,
066ef9c2 JMH	487	u8 sy)
1da177e4 LT	488	{
	489	unsigned long flags;
	490	spin_lock_irqsave(&iso->lock, flags);
	491
	492	if (iso->n_ready_packets == iso->buf_packets) {
	493	/* overflow! */
	494	atomic_inc(&iso->overflows);
1934b8b6 BC	495	/* Record size of this discarded packet */
1934b8b6 BC	496	iso->bytes_discarded += total_len;
1da177e4 LT	497	} else {
	498	struct hpsb_iso_packet_info *info = &iso->infos[iso->pkt_dma];
	499	info->offset = offset;
	500	info->len = len;
1934b8b6	501	info->total_len = total_len;
1da177e4 LT	502	info->cycle = cycle;
	503	info->channel = channel;
	504	info->tag = tag;
	505	info->sy = sy;
	506
066ef9c2	507	iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;
1da177e4 LT	508	iso->n_ready_packets++;
	509	}
	510
	511	spin_unlock_irqrestore(&iso->lock, flags);
	512	}
	513
afd6546d SR	514	/**
	515	* hpsb_iso_recv_release_packets - release packets, reuse buffer
	516	*
	517	* @n_packets have been read out of the buffer, re-use the buffer space
	518	*/
1da177e4 LT	519	int hpsb_iso_recv_release_packets(struct hpsb_iso *iso, unsigned int n_packets)
	520	{
	521	unsigned long flags;
	522	unsigned int i;
	523	int rv = 0;
	524
	525	if (iso->type != HPSB_ISO_RECV)
	526	return -1;
	527
	528	spin_lock_irqsave(&iso->lock, flags);
	529	for (i = 0; i < n_packets; i++) {
	530	rv = iso->host->driver->isoctl(iso, RECV_RELEASE,
066ef9c2 JMH	531	(unsigned long)&iso->infos[iso->
066ef9c2 JMH	532	first_packet]);
1da177e4 LT	533	if (rv)
	534	break;
	535
066ef9c2	536	iso->first_packet = (iso->first_packet + 1) % iso->buf_packets;
1da177e4	537	iso->n_ready_packets--;
1934b8b6 BC	538
1934b8b6 BC	539	/* release memory from packets discarded when queue was full */
066ef9c2	540	if (iso->n_ready_packets == 0) { /* Release only after all prior packets handled */
1934b8b6 BC	541	if (iso->bytes_discarded != 0) {
	542	struct hpsb_iso_packet_info inf;
	543	inf.total_len = iso->bytes_discarded;
	544	iso->host->driver->isoctl(iso, RECV_RELEASE,
066ef9c2	545	(unsigned long)&inf);
1934b8b6 BC	546	iso->bytes_discarded = 0;
	547	}
	548	}
1da177e4 LT	549	}
	550	spin_unlock_irqrestore(&iso->lock, flags);
	551	return rv;
	552	}
	553
afd6546d SR	554	/**
	555	* hpsb_iso_wake
	556	*
	557	* Available to low-level drivers.
	558	*
	559	* Call to wake waiting processes after buffer space has opened up.
	560	*/
1da177e4 LT	561	void hpsb_iso_wake(struct hpsb_iso *iso)
	562	{
	563	wake_up_interruptible(&iso->waitq);
	564
	565	if (iso->callback)
	566	iso->callback(iso);
	567	}