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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [ieee1394/] [iso.c] - Blame information for rev 1774

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/*
 * 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/slab.h>
#include <linux/sched.h>
#include "iso.h"
 
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;
}
 
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 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 (irq_interval < 1 || irq_interval > buf_packets / 2)
                irq_interval = buf_packets / 2;
 
        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;
        dma_region_init(&iso->data_buf);
        iso->buf_size = round_up_to_page(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->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;
}
 
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;
}
 
 
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, 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;
}
 
struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,
                                    unsigned int data_buf_size,
                                    unsigned int buf_packets,
                                    int channel,
                                    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, 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;
}
 
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);
}
 
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);
}
 
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);
}
 
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;
}
 
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;
        else if (prebuffer == 0)
                prebuffer = 1;
 
        if (prebuffer > iso->buf_packets)
                prebuffer = iso->buf_packets;
 
        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;
}
 
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;
}
 
 
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;
}
 
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);
}
 
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);
}
 
void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 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);
        } else {
                struct hpsb_iso_packet_info *info = &iso->infos[iso->pkt_dma];
                info->offset = offset;
                info->len = 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);
}
 
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--;
        }
        spin_unlock_irqrestore(&iso->lock, flags);
        return rv;
}
 
void hpsb_iso_wake(struct hpsb_iso *iso)
{
        wake_up_interruptible(&iso->waitq);
 
        if (iso->callback)
                iso->callback(iso);
}

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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [ieee1394/] [iso.c] - Blame information for rev 1774

Line No.	Rev	Author	Line
1	1275	phoenix	`/*`
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
12			`#include <linux/slab.h>`
13			`#include <linux/sched.h>`
14			`#include "iso.h"`
15
16			`void hpsb_iso_stop(struct hpsb_iso *iso)`
17			`{`
18			`if (!(iso->flags & HPSB_ISO_DRIVER_STARTED))`
19			`return;`
20
21			`iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?`
22			`XMIT_STOP : RECV_STOP, 0);`
23			`iso->flags &= ~HPSB_ISO_DRIVER_STARTED;`
24			`}`
25
26			`void hpsb_iso_shutdown(struct hpsb_iso *iso)`
27			`{`
28			`if (iso->flags & HPSB_ISO_DRIVER_INIT) {`
29			`hpsb_iso_stop(iso);`
30			`iso->host->driver->isoctl(iso, iso->type == HPSB_ISO_XMIT ?`
31			`XMIT_SHUTDOWN : RECV_SHUTDOWN, 0);`
32			`iso->flags &= ~HPSB_ISO_DRIVER_INIT;`
33			`}`
34
35			`dma_region_free(&iso->data_buf);`
36			`kfree(iso);`
37			`}`
38
39			`static struct hpsb_iso* hpsb_iso_common_init(struct hpsb_host *host, enum hpsb_iso_type type,`
40			`unsigned int data_buf_size,`
41			`unsigned int buf_packets,`
42			`int channel,`
43			`int irq_interval,`
44			`void (callback)(struct hpsb_iso))`
45			`{`
46			`struct hpsb_iso *iso;`
47			`int dma_direction;`
48
49			`/* make sure driver supports the ISO API */`
50			`if (!host->driver->isoctl) {`
51			`printk(KERN_INFO "ieee1394: host driver '%s' does not support the rawiso API\n",`
52			`host->driver->name);`
53			`return NULL;`
54			`}`
55
56			`/* sanitize parameters */`
57
58			`if (buf_packets < 2)`
59			`buf_packets = 2;`
60
61			`if (irq_interval < 1 \|\| irq_interval > buf_packets / 2)`
62			`irq_interval = buf_packets / 2;`
63
64			`if (channel < -1 \|\| channel >= 64)`
65			`return NULL;`
66
67			`/* channel = -1 is OK for multi-channel recv but not for xmit */`
68			`if (type == HPSB_ISO_XMIT && channel < 0)`
69			`return NULL;`
70
71			`/* allocate and write the struct hpsb_iso */`
72
73			`iso = kmalloc(sizeof(iso) + buf_packets sizeof(struct hpsb_iso_packet_info), GFP_KERNEL);`
74			`if (!iso)`
75			`return NULL;`
76
77			`iso->infos = (struct hpsb_iso_packet_info *)(iso + 1);`
78
79			`iso->type = type;`
80			`iso->host = host;`
81			`iso->hostdata = NULL;`
82			`iso->callback = callback;`
83			`init_waitqueue_head(&iso->waitq);`
84			`iso->channel = channel;`
85			`iso->irq_interval = irq_interval;`
86			`dma_region_init(&iso->data_buf);`
87			`iso->buf_size = round_up_to_page(data_buf_size);`
88			`iso->buf_packets = buf_packets;`
89			`iso->pkt_dma = 0;`
90			`iso->first_packet = 0;`
91			`spin_lock_init(&iso->lock);`
92
93			`if (iso->type == HPSB_ISO_XMIT) {`
94			`iso->n_ready_packets = iso->buf_packets;`
95			`dma_direction = PCI_DMA_TODEVICE;`
96			`} else {`
97			`iso->n_ready_packets = 0;`
98			`dma_direction = PCI_DMA_FROMDEVICE;`
99			`}`
100
101			`atomic_set(&iso->overflows, 0);`
102			`iso->flags = 0;`
103			`iso->prebuffer = 0;`
104
105			`/* allocate the packet buffer */`
106			`if (dma_region_alloc(&iso->data_buf, iso->buf_size, host->pdev, dma_direction))`
107			`goto err;`
108
109			`return iso;`
110
111			`err:`
112			`hpsb_iso_shutdown(iso);`
113			`return NULL;`
114			`}`
115
116			`int hpsb_iso_n_ready(struct hpsb_iso* iso)`
117			`{`
118			`unsigned long flags;`
119			`int val;`
120
121			`spin_lock_irqsave(&iso->lock, flags);`
122			`val = iso->n_ready_packets;`
123			`spin_unlock_irqrestore(&iso->lock, flags);`
124
125			`return val;`
126			`}`
127
128
129			`struct hpsb_iso* hpsb_iso_xmit_init(struct hpsb_host *host,`
130			`unsigned int data_buf_size,`
131			`unsigned int buf_packets,`
132			`int channel,`
133			`int speed,`
134			`int irq_interval,`
135			`void (callback)(struct hpsb_iso))`
136			`{`
137			`struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_XMIT,`
138			`data_buf_size, buf_packets,`
139			`channel, irq_interval, callback);`
140			`if (!iso)`
141			`return NULL;`
142
143			`iso->speed = speed;`
144
145			`/* tell the driver to start working */`
146			`if (host->driver->isoctl(iso, XMIT_INIT, 0))`
147			`goto err;`
148
149			`iso->flags \|= HPSB_ISO_DRIVER_INIT;`
150			`return iso;`
151
152			`err:`
153			`hpsb_iso_shutdown(iso);`
154			`return NULL;`
155			`}`
156
157			`struct hpsb_iso* hpsb_iso_recv_init(struct hpsb_host *host,`
158			`unsigned int data_buf_size,`
159			`unsigned int buf_packets,`
160			`int channel,`
161			`int irq_interval,`
162			`void (callback)(struct hpsb_iso))`
163			`{`
164			`struct hpsb_iso *iso = hpsb_iso_common_init(host, HPSB_ISO_RECV,`
165			`data_buf_size, buf_packets,`
166			`channel, irq_interval, callback);`
167			`if (!iso)`
168			`return NULL;`
169
170			`/* tell the driver to start working */`
171			`if (host->driver->isoctl(iso, RECV_INIT, 0))`
172			`goto err;`
173
174			`iso->flags \|= HPSB_ISO_DRIVER_INIT;`
175			`return iso;`
176
177			`err:`
178			`hpsb_iso_shutdown(iso);`
179			`return NULL;`
180			`}`
181
182			`int hpsb_iso_recv_listen_channel(struct hpsb_iso *iso, unsigned char channel)`
183			`{`
184			`if (iso->type != HPSB_ISO_RECV \|\| iso->channel != -1 \|\| channel >= 64)`
185			`return -EINVAL;`
186			`return iso->host->driver->isoctl(iso, RECV_LISTEN_CHANNEL, channel);`
187			`}`
188
189			`int hpsb_iso_recv_unlisten_channel(struct hpsb_iso *iso, unsigned char channel)`
190			`{`
191			`if (iso->type != HPSB_ISO_RECV \|\| iso->channel != -1 \|\| channel >= 64)`
192			`return -EINVAL;`
193			`return iso->host->driver->isoctl(iso, RECV_UNLISTEN_CHANNEL, channel);`
194			`}`
195
196			`int hpsb_iso_recv_set_channel_mask(struct hpsb_iso *iso, u64 mask)`
197			`{`
198			`if (iso->type != HPSB_ISO_RECV \|\| iso->channel != -1)`
199			`return -EINVAL;`
200			`return iso->host->driver->isoctl(iso, RECV_SET_CHANNEL_MASK, (unsigned long) &mask);`
201			`}`
202
203			`int hpsb_iso_recv_flush(struct hpsb_iso *iso)`
204			`{`
205			`if (iso->type != HPSB_ISO_RECV)`
206			`return -EINVAL;`
207			`return iso->host->driver->isoctl(iso, RECV_FLUSH, 0);`
208			`}`
209
210			`static int do_iso_xmit_start(struct hpsb_iso *iso, int cycle)`
211			`{`
212			`int retval = iso->host->driver->isoctl(iso, XMIT_START, cycle);`
213			`if (retval)`
214			`return retval;`
215
216			`iso->flags \|= HPSB_ISO_DRIVER_STARTED;`
217			`return retval;`
218			`}`
219
220			`int hpsb_iso_xmit_start(struct hpsb_iso *iso, int cycle, int prebuffer)`
221			`{`
222			`if (iso->type != HPSB_ISO_XMIT)`
223			`return -1;`
224
225			`if (iso->flags & HPSB_ISO_DRIVER_STARTED)`
226			`return 0;`
227
228			`if (cycle < -1)`
229			`cycle = -1;`
230			`else if (cycle >= 8000)`
231			`cycle %= 8000;`
232
233			`iso->xmit_cycle = cycle;`
234
235			`if (prebuffer < 0)`
236			`prebuffer = iso->buf_packets;`
237			`else if (prebuffer == 0)`
238			`prebuffer = 1;`
239
240			`if (prebuffer > iso->buf_packets)`
241			`prebuffer = iso->buf_packets;`
242
243			`iso->prebuffer = prebuffer;`
244
245			`/* remember the starting cycle; DMA will commence from xmit_queue_packets()`
246			`once enough packets have been buffered */`
247			`iso->start_cycle = cycle;`
248
249			`return 0;`
250			`}`
251
252			`int hpsb_iso_recv_start(struct hpsb_iso *iso, int cycle, int tag_mask, int sync)`
253			`{`
254			`int retval = 0;`
255			`int isoctl_args[3];`
256
257			`if (iso->type != HPSB_ISO_RECV)`
258			`return -1;`
259
260			`if (iso->flags & HPSB_ISO_DRIVER_STARTED)`
261			`return 0;`
262
263			`if (cycle < -1)`
264			`cycle = -1;`
265			`else if (cycle >= 8000)`
266			`cycle %= 8000;`
267
268			`isoctl_args[0] = cycle;`
269
270			`if (tag_mask < 0)`
271			`/* match all tags */`
272			`tag_mask = 0xF;`
273			`isoctl_args[1] = tag_mask;`
274
275			`isoctl_args[2] = sync;`
276
277			`retval = iso->host->driver->isoctl(iso, RECV_START, (unsigned long) &isoctl_args[0]);`
278			`if (retval)`
279			`return retval;`
280
281			`iso->flags \|= HPSB_ISO_DRIVER_STARTED;`
282			`return retval;`
283			`}`
284
285			`/* check to make sure the user has not supplied bogus values of offset/len`
286			`that would cause the kernel to access memory outside the buffer */`
287
288			`static int hpsb_iso_check_offset_len(struct hpsb_iso *iso,`
289			`unsigned int offset, unsigned short len,`
290			`unsigned int out_offset, unsigned short out_len)`
291			`{`
292			`if (offset >= iso->buf_size)`
293			`return -EFAULT;`
294
295			`/* make sure the packet does not go beyond the end of the buffer */`
296			`if (offset + len > iso->buf_size)`
297			`return -EFAULT;`
298
299			`/* check for wrap-around */`
300			`if (offset + len < offset)`
301			`return -EFAULT;`
302
303			`/* now we can trust 'offset' and 'length' */`
304			`*out_offset = offset;`
305			`*out_len = len;`
306
307			`return 0;`
308			`}`
309
310
311			`int hpsb_iso_xmit_queue_packet(struct hpsb_iso *iso, u32 offset, u16 len, u8 tag, u8 sy)`
312			`{`
313			`struct hpsb_iso_packet_info *info;`
314			`unsigned long flags;`
315			`int rv;`
316
317			`if (iso->type != HPSB_ISO_XMIT)`
318			`return -EINVAL;`
319
320			`/* is there space in the buffer? */`
321			`if (iso->n_ready_packets <= 0) {`
322			`return -EBUSY;`
323			`}`
324
325			`info = &iso->infos[iso->first_packet];`
326
327			`/* check for bogus offset/length */`
328			`if (hpsb_iso_check_offset_len(iso, offset, len, &info->offset, &info->len))`
329			`return -EFAULT;`
330
331			`info->tag = tag;`
332			`info->sy = sy;`
333
334			`spin_lock_irqsave(&iso->lock, flags);`
335
336			`rv = iso->host->driver->isoctl(iso, XMIT_QUEUE, (unsigned long) info);`
337			`if (rv)`
338			`goto out;`
339
340			`/* increment cursors */`
341			`iso->first_packet = (iso->first_packet+1) % iso->buf_packets;`
342			`iso->xmit_cycle = (iso->xmit_cycle+1) % 8000;`
343			`iso->n_ready_packets--;`
344
345			`if (iso->prebuffer != 0) {`
346			`iso->prebuffer--;`
347			`if (iso->prebuffer <= 0) {`
348			`iso->prebuffer = 0;`
349			`rv = do_iso_xmit_start(iso, iso->start_cycle);`
350			`}`
351			`}`
352
353			`out:`
354			`spin_unlock_irqrestore(&iso->lock, flags);`
355			`return rv;`
356			`}`
357
358			`int hpsb_iso_xmit_sync(struct hpsb_iso *iso)`
359			`{`
360			`if (iso->type != HPSB_ISO_XMIT)`
361			`return -EINVAL;`
362
363			`return wait_event_interruptible(iso->waitq, hpsb_iso_n_ready(iso) == iso->buf_packets);`
364			`}`
365
366			`void hpsb_iso_packet_sent(struct hpsb_iso *iso, int cycle, int error)`
367			`{`
368			`unsigned long flags;`
369			`spin_lock_irqsave(&iso->lock, flags);`
370
371			`/* predict the cycle of the next packet to be queued */`
372
373			`/* jump ahead by the number of packets that are already buffered */`
374			`cycle += iso->buf_packets - iso->n_ready_packets;`
375			`cycle %= 8000;`
376
377			`iso->xmit_cycle = cycle;`
378			`iso->n_ready_packets++;`
379			`iso->pkt_dma = (iso->pkt_dma + 1) % iso->buf_packets;`
380
381			`if (iso->n_ready_packets == iso->buf_packets \|\| error != 0) {`
382			`/* the buffer has run empty! */`
383			`atomic_inc(&iso->overflows);`
384			`}`
385
386			`spin_unlock_irqrestore(&iso->lock, flags);`
387			`}`
388
389			`void hpsb_iso_packet_received(struct hpsb_iso *iso, u32 offset, u16 len,`
390			`u16 cycle, u8 channel, u8 tag, u8 sy)`
391			`{`
392			`unsigned long flags;`
393			`spin_lock_irqsave(&iso->lock, flags);`
394
395			`if (iso->n_ready_packets == iso->buf_packets) {`
396			`/* overflow! */`
397			`atomic_inc(&iso->overflows);`
398			`} else {`
399			`struct hpsb_iso_packet_info *info = &iso->infos[iso->pkt_dma];`
400			`info->offset = offset;`
401			`info->len = len;`
402			`info->cycle = cycle;`
403			`info->channel = channel;`
404			`info->tag = tag;`
405			`info->sy = sy;`
406
407			`iso->pkt_dma = (iso->pkt_dma+1) % iso->buf_packets;`
408			`iso->n_ready_packets++;`
409			`}`
410
411			`spin_unlock_irqrestore(&iso->lock, flags);`
412			`}`
413
414			`int hpsb_iso_recv_release_packets(struct hpsb_iso *iso, unsigned int n_packets)`
415			`{`
416			`unsigned long flags;`
417			`unsigned int i;`
418			`int rv = 0;`
419
420			`if (iso->type != HPSB_ISO_RECV)`
421			`return -1;`
422
423			`spin_lock_irqsave(&iso->lock, flags);`
424			`for (i = 0; i < n_packets; i++) {`
425			`rv = iso->host->driver->isoctl(iso, RECV_RELEASE,`
426			`(unsigned long) &iso->infos[iso->first_packet]);`
427			`if (rv)`
428			`break;`
429
430			`iso->first_packet = (iso->first_packet+1) % iso->buf_packets;`
431			`iso->n_ready_packets--;`
432			`}`
433			`spin_unlock_irqrestore(&iso->lock, flags);`
434			`return rv;`
435			`}`
436
437			`void hpsb_iso_wake(struct hpsb_iso *iso)`
438			`{`
439			`wake_up_interruptible(&iso->waitq);`
440
441			`if (iso->callback)`
442			`iso->callback(iso);`
443			`}`