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-rw-r--r--drivers/ieee1394/iso.c568
1 files changed, 568 insertions, 0 deletions
diff --git a/drivers/ieee1394/iso.c b/drivers/ieee1394/iso.c
new file mode 100644
index 0000000..1cf6487
--- /dev/null
+++ b/drivers/ieee1394/iso.c
@@ -0,0 +1,568 @@
+/*
+ * 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/mm.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);
+}
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