diff options
Diffstat (limited to 'drivers/ieee1394/iso.c')
-rw-r--r-- | drivers/ieee1394/iso.c | 451 |
1 files changed, 451 insertions, 0 deletions
diff --git a/drivers/ieee1394/iso.c b/drivers/ieee1394/iso.c new file mode 100644 index 0000000..f057591 --- /dev/null +++ b/drivers/ieee1394/iso.c @@ -0,0 +1,451 @@ +/* + * 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 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) /* really interrupt for each packet*/ + irq_interval = 1; + else if ((irq_interval < 0) || (irq_interval > buf_packets / 4)) + irq_interval = buf_packets / 4; + + 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->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, 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; +} + +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; +} + +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); +} |