/* -*- c-basic-offset: 8 -*-
*
* amdtp.c - Audio and Music Data Transmission Protocol Driver
* Copyright (C) 2001 Kristian Høgsberg
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/* OVERVIEW
* --------
*
* The AMDTP driver is designed to expose the IEEE1394 bus as a
* regular OSS soundcard, i.e. you can link /dev/dsp to /dev/amdtp and
* then your favourite MP3 player, game or whatever sound program will
* output to an IEEE1394 isochronous channel. The signal destination
* could be a set of IEEE1394 loudspeakers (if and when such things
* become available) or an amplifier with IEEE1394 input (like the
* Sony STR-LSA1). The driver only handles the actual streaming, some
* connection management is also required for this to actually work.
* That is outside the scope of this driver, and furthermore it is not
* really standardized yet.
*
* The Audio and Music Data Tranmission Protocol is available at
*
* http://www.1394ta.org/Download/Technology/Specifications/2001/AM20Final-jf2.pdf
*
*
* TODO
* ----
*
* - We should be able to change input sample format between LE/BE, as
* we already shift the bytes around when we construct the iso
* packets.
*
* - Fix DMA stop after bus reset!
*
* - Clean up iso context handling in ohci1394.
*
*
* MAYBE TODO
* ----------
*
* - Receive data for local playback or recording. Playback requires
* soft syncing with the sound card.
*
* - Signal processing, i.e. receive packets, do some processing, and
* transmit them again using the same packet structure and timestamps
* offset by processing time.
*
* - Maybe make an ALSA interface, that is, create a file_ops
* implementation that recognizes ALSA ioctls and uses defaults for
* things that can't be controlled through ALSA (iso channel).
*
* Changes:
*
* - Audit copy_from_user in amdtp_write.
* Daniele Bellucci <bellucda@tiscali.it>
*
*/
#include <linux/module.h>
#include <linux/list.h>
#include <linux/sched.h>
#include <linux/types.h>
#include <linux/fs.h>
#include <linux/ioctl.h>
#include <linux/wait.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/poll.h>
#include <linux/compat.h>
#include <linux/cdev.h>
#include <asm/uaccess.h>
#include <asm/atomic.h>
#include "hosts.h"
#include "highlevel.h"
#include "ieee1394.h"
#include "ieee1394_core.h"
#include "ohci1394.h"
#include "amdtp.h"
#include "cmp.h"
#define FMT_AMDTP 0x10
#define FDF_AM824 0x00
#define FDF_SFC_32KHZ 0x00
#define FDF_SFC_44K1HZ 0x01
#define FDF_SFC_48KHZ 0x02
#define FDF_SFC_88K2HZ 0x03
#define FDF_SFC_96KHZ 0x04
#define FDF_SFC_176K4HZ 0x05
#define FDF_SFC_192KHZ 0x06
struct descriptor_block {
struct output_more_immediate {
u32 control;
u32 pad0;
u32 skip;
u32 pad1;
u32 header[4];
} header_desc;
struct output_last {
u32 control;
u32 data_address;
u32 branch;
u32 status;
} payload_desc;
};
struct packet {
struct descriptor_block *db;
dma_addr_t db_bus;
struct iso_packet *payload;
dma_addr_t payload_bus;
};
#include <asm/byteorder.h>
#if defined __BIG_ENDIAN_BITFIELD
struct iso_packet {
/* First quadlet */
unsigned int dbs : 8;
unsigned int eoh0 : 2;
unsigned int sid : 6;
unsigned int dbc : 8;
unsigned int fn : 2;
unsigned int qpc : 3;
unsigned int sph : 1;
unsigned int reserved : 2;
/* Second quadlet */
unsigned int fdf : 8;
unsigned int eoh1 : 2;
unsigned int fmt : 6;
unsigned int syt : 16;
quadlet_t data[0];
};
#elif defined __LITTLE_ENDIAN_BITFIELD
struct iso_packet {
/* First quadlet */
unsigned int sid : 6;
unsigned int eoh0 : 2;
unsigned int dbs : 8;
unsigned int reserved : 2;
unsigned int sph : 1;
unsigned int qpc : 3;
unsigned int fn : 2;
unsigned int dbc : 8;
/* Second quadlet */
unsigned int fmt : 6;
unsigned int eoh1 : 2;
unsigned int fdf : 8;
unsigned int syt : 16;
quadlet_t data[0];
};
#else
#error Unknown bitfield type
#endif
struct fraction {
int integer;
int numerator;
int denominator;
};
#define PACKET_LIST_SIZE 256
#define MAX_PACKET_LISTS 4
struct packet_list {
struct list_head link;
int last_cycle_count;
struct packet packets[PACKET_LIST_SIZE];
};
#define BUFFER_SIZE 128
/* This implements a circular buffer for incoming samples. */
struct buffer {
size_t head, tail, length, size;
unsigned char data[0];
};
struct stream {
int iso_channel;
int format;
int rate;
int dimension;
int fdf;
int mode;
int sample_format;
struct cmp_pcr *opcr;
/* Input samples are copied here. */
struct buffer *input;
/* ISO Packer state */
unsigned char dbc;
struct packet_list *current_packet_list;
int current_packet;
struct fraction ready_samples, samples_per_cycle;
/* We use these to generate control bits when we are packing
* iec958 data.
*/
int iec958_frame_count;
int iec958_rate_code;
/* The cycle_count and cycle_offset fields are used for the
* synchronization timestamps (syt) in the cip header. They
* are incremented by at least a cycle every time we put a
* time stamp in a packet. As we don't time stamp all
* packages, cycle_count isn't updated in every cycle, and
* sometimes it's incremented by 2. Thus, we have
* cycle_count2, which is simply incremented by one with each
* packet, so we can compare it to the transmission time
* written back in the dma programs.
*/
atomic_t cycle_count, cycle_count2;
struct fraction cycle_offset, ticks_per_syt_offset;
int syt_interval;
int stale_count;
/* Theses fields control the sample output to the DMA engine.
* The dma_packet_lists list holds packet lists currently
* queued for dma; the head of the list is currently being
* processed. The last program in a packet list generates an
* interrupt, which removes the head from dma_packet_lists and
* puts it back on the free list.
*/
struct list_head dma_packet_lists;
struct list_head free_packet_lists;
wait_queue_head_t packet_list_wait;
spinlock_t packet_list_lock;
struct ohci1394_iso_tasklet iso_tasklet;
struct pci_pool *descriptor_pool, *packet_pool;
/* Streams at a host controller are chained through this field. */
struct list_head link;
struct amdtp_host *host;
};
struct amdtp_host {
struct hpsb_host *host;
struct ti_ohci *ohci;
struct list_head stream_list;
spinlock_t stream_list_lock;
};
static struct hpsb_highlevel amdtp_highlevel;
/* FIXME: This doesn't belong here... */
#define OHCI1394_CONTEXT_CYCLE_MATCH 0x80000000
#define OHCI1394_CONTEXT_RUN 0x00008000
#define OHCI1394_CONTEXT_WAKE 0x00001000
#define OHCI1394_CONTEXT_DEAD 0x00000800
#define OHCI1394_CONTEXT_ACTIVE 0x00000400
static void ohci1394_start_it_ctx(struct ti_ohci *ohci, int ctx,
dma_addr_t first_cmd, int z, int cycle_match)
{
reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << ctx);
reg_write(ohci, OHCI1394_IsoXmitCommandPtr + ctx * 16, first_cmd | z);
reg_write(ohci, OHCI1394_IsoXmitContextControlClear + ctx * 16, ~0);
wmb();
reg_write(ohci, OHCI1394_IsoXmitContextControlSet + ctx * 16,
OHCI1394_CONTEXT_CYCLE_MATCH | (cycle_match << 16) |
OHCI1394_CONTEXT_RUN);
}
static void ohci1394_wake_it_ctx(struct ti_ohci *ohci, int ctx)
{
reg_write(ohci, OHCI1394_IsoXmitContextControlSet + ctx * 16,
OHCI1394_CONTEXT_WAKE);
}
static void ohci1394_stop_it_ctx(struct ti_ohci *ohci, int ctx, int synchronous)
{
u32 control;
int wait;
reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << ctx);
reg_write(ohci, OHCI1394_IsoXmitContextControlClear + ctx * 16,
OHCI1394_CONTEXT_RUN);
wmb();
if (synchronous) {
for (wait = 0; wait < 5; wait++) {
control = reg_read(ohci, OHCI1394_IsoXmitContextControlSet + ctx * 16);
if ((control & OHCI1394_CONTEXT_ACTIVE) == 0)
break;
schedule_timeout_interruptible(1);
}
}
}
/* Note: we can test if free_packet_lists is empty without aquiring
* the packet_list_lock. The interrupt handler only adds to the free
* list, there is no race condition between testing the list non-empty
* and acquiring the lock.
*/
static struct packet_list *stream_get_free_packet_list(struct stream *s)
{
struct packet_list *pl;
unsigned long flags;
if (list_empty(&s->free_packet_lists))
return NULL;
spin_lock_irqsave(&s->packet_list_lock, flags);
pl = list_entry(s->free_packet_lists.next, struct packet_list, link);
list_del(&pl->link);
spin_unlock_irqrestore(&s->packet_list_lock, flags);
return pl;
}
static void stream_start_dma(struct stream *s, struct packet_list *pl)
{
u32 syt_cycle, cycle_count, start_cycle;
cycle_count = reg_read(s->host->ohci,
OHCI1394_IsochronousCycleTimer) >> 12;
syt_cycle = (pl->last_cycle_count - PACKET_LIST_SIZE + 1) & 0x0f;
/* We program the DMA controller to start transmission at
* least 17 cycles from now - this happens when the lower four
* bits of cycle_count is 0x0f and syt_cycle is 0, in this
* case the start cycle is cycle_count - 15 + 32. */
start_cycle = (cycle_count & ~0x0f) + 32 + syt_cycle;
if ((start_cycle & 0x1fff) >= 8000)
start_cycle = start_cycle - 8000 + 0x2000;
ohci1394_start_it_ctx(s->host->ohci, s->iso_tasklet.context,
pl->packets[0].db_bus, 3,
start_cycle & 0x7fff);
}
static void stream_put_dma_packet_list(struct stream *s,
struct packet_list *pl)
{
unsigned long flags;
struct packet_list *prev;
/* Remember the cycle_count used for timestamping the last packet. */
pl->last_cycle_count = atomic_read(&s->cycle_count2) - 1;
pl->packets[PACKET_LIST_SIZE - 1].db->payload_desc.branch = 0;
spin_lock_irqsave(&s->packet_list_lock, flags);
list_add_tail(&pl->link, &s->dma_packet_lists);
spin_unlock_irqrestore(&s->packet_list_lock, flags);
prev = list_entry(pl->link.prev, struct packet_list, link);
if (pl->link.prev != &s->dma_packet_lists) {
struct packet *last = &prev->packets[PACKET_LIST_SIZE - 1];
last->db->payload_desc.branch = pl->packets[0].db_bus | 3;
last->db->header_desc.skip = pl->packets[0].db_bus | 3;
ohci1394_wake_it_ctx(s->host->ohci, s->iso_tasklet.context);
}
else
stream_start_dma(s, pl);
}
static void stream_shift_packet_lists(unsigned long l)
{
struct stream *s = (struct stream *) l;
struct packet_list *pl;
struct packet *last;
int diff;
if (list_empty(&s->dma_packet_lists)) {
HPSB_ERR("empty dma_packet_lists in %s", __FUNCTION__);
return;
}
/* Now that we know the list is non-empty, we can get the head
* of the list without locking, because the process context
* only adds to the tail.
*/
pl = list_entry(s->dma_packet_lists.next, struct packet_list, link);
last = &pl->packets[PACKET_LIST_SIZE - 1];
/* This is weird... if we stop dma processing in the middle of
* a packet list, the dma context immediately generates an
* interrupt if we enable it again later. This only happens
* when amdtp_release is interrupted while waiting for dma to
* complete, though. Anyway, we detect this by seeing that
* the status of the dma descriptor that we expected an
* interrupt from is still 0.
*/
if (last->db->payload_desc.status == 0) {
HPSB_INFO("weird interrupt...");
return;
}
/* If the last descriptor block does not specify a branch
* address, we have a sample underflow.
*/
if (last->db->payload_desc.branch == 0)
HPSB_INFO("FIXME: sample underflow...");
/* Here we check when (which cycle) the last packet was sent
* and compare it to what the iso packer was using at the
* time. If there is a mismatch, we adjust the cycle count in
* the iso packer. However, there are still up to
* MAX_PACKET_LISTS packet lists queued with bad time stamps,
* so we disable time stamp monitoring for the next
* MAX_PACKET_LISTS packet lists.
*/
diff = (last->db->payload_desc.status - pl->last_cycle_count) & 0xf;
if (diff > 0 && s->stale_count == 0) {
atomic_add(diff, &s->cycle_count);
atomic_add(diff, &s->cycle_count2);
s->stale_count = MAX_PACKET_LISTS;
}
if (s->stale_count > 0)
s->stale_count--;
/* Finally, we move the packet list that was just processed
* back to the free list, and notify any waiters.
*/
spin_lock(&s->packet_list_lock);
list_del(&pl->link);
list_add_tail(&pl->link, &s->free_packet_lists);
spin_unlock(&s->packet_list_lock);
wake_up_interruptible(&s->packet_list_wait);
}
static struct packet *stream_current_packet(struct stream *s)
{
if (s->current_packet_list == NULL &&
(s->current_packet_list = stream_get_free_packet_list(s)) == NULL)
return NULL;
return &s->current_packet_list->packets[s->current_packet];
}
static void stream_queue_packet(struct stream *s)
{
s->current_packet++;
if (s->current_packet == PACKET_LIST_SIZE) {
stream_put_dma_packet_list(s, s->current_packet_list);
s->current_packet_list = NULL;
s->current_packet = 0;
}
}
/* Integer fractional math. When we transmit a 44k1Hz signal we must
* send 5 41/80 samples per isochronous cycle, as these occur 8000
* times a second. Of course, we must send an integral number of
* samples in a packet, so we use the integer math to alternate
* between sending 5 and 6 samples per packet.
*/
static void fraction_init(struct fraction *f, int numerator, int denominator)
{
f->integer = numerator / denominator;
f->numerator = numerator % denominator;
f->denominator = denominator;
}
static __inline__ void fraction_add(struct fraction *dst,
struct fraction *src1,
struct fraction *src2)
{
/* assert: src1->denominator == src2->denominator */
int sum, denom;
/* We use these two local variables to allow gcc to optimize
* the division and the modulo into only one division. */
sum = src1->numerator + src2->numerator;
denom = src1->denominator;
dst->integer = src1->integer + src2->integer + sum / denom;
dst->numerator = sum % denom;
dst->denominator = denom;
}
static __inline__ void fraction_sub_int(struct fraction *dst,
struct fraction *src, int integer)
{
dst->integer = src->integer - integer;
dst->numerator = src->numerator;
dst->denominator = src->denominator;
}
static __inline__ int fraction_floor(struct fraction *frac)
{
return frac->integer;
}
static __inline__ int fraction_ceil(struct fraction *frac)
{
return frac->integer + (frac->numerator > 0 ? 1 : 0);
}
static void packet_initialize(struct packet *p, struct packet *next)
{
/* Here we initialize the dma descriptor block for
* transferring one iso packet. We use two descriptors per
* packet: an OUTPUT_MORE_IMMMEDIATE descriptor for the
* IEEE1394 iso packet header and an OUTPUT_LAST descriptor
* for the payload.
*/
p->db->header_desc.control =
DMA_CTL_OUTPUT_MORE | DMA_CTL_IMMEDIATE | 8;
if (next) {
p->db->payload_desc.control =
DMA_CTL_OUTPUT_LAST | DMA_CTL_BRANCH;
p->db->payload_desc.branch = next->db_bus | 3;
p->db->header_desc.skip = next->db_bus | 3;
}
else {
p->db->payload_desc.control =
DMA_CTL_OUTPUT_LAST | DMA_CTL_BRANCH |
DMA_CTL_UPDATE | DMA_CTL_IRQ;
p->db->payload_desc.branch = 0;
p->db->header_desc.skip = 0;
}
p->db->payload_desc.data_address = p->payload_bus;
p->db->payload_desc.status = 0;
}
static struct packet_list *packet_list_alloc(struct stream *s)
{
int i;
struct packet_list *pl;
struct packet *next;
pl = kmalloc(sizeof *pl, SLAB_KERNEL);
if (pl == NULL)
return NULL;
for (i = 0; i < PACKET_LIST_SIZE; i++) {
struct packet *p = &pl->packets[i];
p->db = pci_pool_alloc(s->descriptor_pool, SLAB_KERNEL,
&p->db_bus);
p->payload = pci_pool_alloc(s->packet_pool, SLAB_KERNEL,
&p->payload_bus);
}
for (i = 0; i < PACKET_LIST_SIZE; i++) {
if (i < PACKET_LIST_SIZE - 1)
next = &pl->packets[i + 1];
else
next = NULL;
packet_initialize(&pl->packets[i], next);
}
return pl;
}
static void packet_list_free(struct packet_list *pl, struct stream *s)
{
int i;
for (i = 0; i < PACKET_LIST_SIZE; i++) {
struct packet *p = &pl->packets[i];
pci_pool_free(s->descriptor_pool, p->db, p->db_bus);
pci_pool_free(s->packet_pool, p->payload, p->payload_bus);
}
kfree(pl);
}
static struct buffer *buffer_alloc(int size)
{
struct buffer *b;
b = kmalloc(sizeof *b + size, SLAB_KERNEL);
if (b == NULL)
return NULL;
b->head = 0;
b->tail = 0;
b->length = 0;
b->size = size;
return b;
}
static unsigned char *buffer_get_bytes(struct buffer *buffer, int size)
{
unsigned char *p;
if (buffer->head + size > buffer->size)
BUG();
p = &buffer->data[buffer->head];
buffer->head += size;
if (buffer->head == buffer->size)
buffer->head = 0;
buffer->length -= size;
return p;
}
static unsigned char *buffer_put_bytes(struct buffer *buffer,
size_t max, size_t *actual)
{
size_t length;
unsigned char *p;
p = &buffer->data[buffer->tail];
length = min(buffer->size - buffer->length, max);
if (buffer->tail + length < buffer->size) {
*actual = length;
buffer->tail += length;
}
else {
*actual = buffer->size - buffer->tail;
buffer->tail = 0;
}
buffer->length += *actual;
return p;
}
static u32 get_iec958_header_bits(struct stream *s, int sub_frame, u32 sample)
{
int csi, parity, shift;
int block_start;
u32 bits;
switch (s->iec958_frame_count) {
case 1:
csi = s->format == AMDTP_FORMAT_IEC958_AC3;
break;
case 2:
case 9:
csi = 1;
break;
case 24 ... 27:
csi = (s->iec958_rate_code >> (27 - s->iec958_frame_count)) & 0x01;
break;
default:
csi = 0;
break;
}
block_start = (s->iec958_frame_count == 0 && sub_frame == 0);
/* The parity bit is the xor of the sample bits and the
* channel status info bit. */
for (shift = 16, parity = sample ^ csi; shift > 0; shift >>= 1)
parity ^= (parity >> shift);
bits = (block_start << 5) | /* Block start bit */
((sub_frame == 0) << 4) | /* Subframe bit */
((parity & 1) << 3) | /* Parity bit */
(csi << 2); /* Channel status info bit */
return bits;
}
static u32 get_header_bits(struct stream *s, int sub_frame, u32 sample)
{
switch (s->format) {
case AMDTP_FORMAT_IEC958_PCM:
case AMDTP_FORMAT_IEC958_AC3:
return get_iec958_header_bits(s, sub_frame, sample);
case AMDTP_FORMAT_RAW:
return 0x40;
default:
return 0;
}
}
static void fill_payload_le16(struct stream *s, quadlet_t *data, int nevents)
{
quadlet_t *event, sample, bits;
unsigned char *p;
int i, j;
for (i = 0, event = data; i < nevents; i++) {
for (j = 0; j < s->dimension; j++) {
p = buffer_get_bytes(s->input, 2);
sample = (p[1] << 16) | (p[0] << 8);
bits = get_header_bits(s, j, sample);
event[j] = cpu_to_be32((bits << 24) | sample);
}
event += s->dimension;
if (++s->iec958_frame_count == 192)
s->iec958_frame_count = 0;
}
}
static void fill_packet(struct stream *s, struct packet *packet, int nevents)
{
int syt_index, syt, size;
u32 control;
size = (nevents * s->dimension + 2) * sizeof(quadlet_t);
/* Update DMA descriptors */
packet->db->payload_desc.status = 0;
control = packet->db->payload_desc.control & 0xffff0000;
packet->db->payload_desc.control = control | size;
/* Fill IEEE1394 headers */
packet->db->header_desc.header[0] =
(IEEE1394_SPEED_100 << 16) | (0x01 << 14) |
(s->iso_channel << 8) | (TCODE_ISO_DATA << 4);
packet->db->header_desc.header[1] = size << 16;
/* Calculate synchronization timestamp (syt). First we
* determine syt_index, that is, the index in the packet of
* the sample for which the timestamp is valid. */
syt_index = (s->syt_interval - s->dbc) & (s->syt_interval - 1);
if (syt_index < nevents) {
syt = ((atomic_read(&s->cycle_count) << 12) |
s->cycle_offset.integer) & 0xffff;
fraction_add(&s->cycle_offset,
&s->cycle_offset, &s->ticks_per_syt_offset);
/* This next addition should be modulo 8000 (0x1f40),
* but we only use the lower 4 bits of cycle_count, so
* we don't need the modulo. */
atomic_add(s->cycle_offset.integer / 3072, &s->cycle_count);
s->cycle_offset.integer %= 3072;
}
else
syt = 0xffff;
atomic_inc(&s->cycle_count2);
/* Fill cip header */
packet->payload->eoh0 = 0;
packet->payload->sid = s->host->host->node_id & 0x3f;
packet->payload->dbs = s->dimension;
packet->payload->fn = 0;
packet->payload->qpc = 0;
packet->payload->sph = 0;
packet->payload->reserved = 0;
packet->payload->dbc = s->dbc;
packet->payload->eoh1 = 2;
packet->payload->fmt = FMT_AMDTP;
packet->payload->fdf = s->fdf;
packet->payload->syt = cpu_to_be16(syt);
switch (s->sample_format) {
case AMDTP_INPUT_LE16:
fill_payload_le16(s, packet->payload->data, nevents);
break;
}
s->dbc += nevents;
}
static void stream_flush(struct stream *s)
{
struct packet *p;
int nevents;
struct fraction next;
/* The AMDTP specifies two transmission modes: blocking and
* non-blocking. In blocking mode you always transfer
* syt_interval or zero samples, whereas in non-blocking mode
* you send as many samples as you have available at transfer
* time.
*
* The fraction samples_per_cycle specifies the number of
* samples that become available per cycle. We add this to
* the fraction ready_samples, which specifies the number of
* leftover samples from the previous transmission. The sum,
* stored in the fraction next, specifies the number of
* samples available for transmission, and from this we
* determine the number of samples to actually transmit.
*/
while (1) {
fraction_add(&next, &s->ready_samples, &s->samples_per_cycle);
if (s->mode == AMDTP_MODE_BLOCKING) {
if (fraction_floor(&next) >= s->syt_interval)
nevents = s->syt_interval;
else
nevents = 0;
}
else
nevents = fraction_floor(&next);
p = stream_current_packet(s);
if (s->input->length < nevents * s->dimension * 2 || p == NULL)
break;
fill_packet(s, p, nevents);
stream_queue_packet(s);
/* Now that we have successfully queued the packet for
* transmission, we update the fraction ready_samples. */
fraction_sub_int(&s->ready_samples, &next, nevents);
}
}
static int stream_alloc_packet_lists(struct stream *s)
{
int max_nevents, max_packet_size, i;
if (s->mode == AMDTP_MODE_BLOCKING)
max_nevents = s->syt_interval;
else
max_nevents = fraction_ceil(&s->samples_per_cycle);
max_packet_size = max_nevents * s->dimension * 4 + 8;
s->packet_pool = pci_pool_create("packet pool", s->host->ohci->dev,
max_packet_size, 0, 0);
if (s->packet_pool == NULL)
return -1;
INIT_LIST_HEAD(&s->free_packet_lists);
INIT_LIST_HEAD(&s->dma_packet_lists);
for (i = 0; i < MAX_PACKET_LISTS; i++) {
struct packet_list *pl = packet_list_alloc(s);
if (pl == NULL)
break;
list_add_tail(&pl->link, &s->free_packet_lists);
}
return i < MAX_PACKET_LISTS ? -1 : 0;
}
static void stream_free_packet_lists(struct stream *s)
{
struct packet_list *packet_l, *packet_l_next;
if (s->current_packet_list != NULL)
packet_list_free(s->current_packet_list, s);
list_for_each_entry_safe(packet_l, packet_l_next, &s->dma_packet_lists, link)
packet_list_free(packet_l, s);
list_for_each_entry_safe(packet_l, packet_l_next, &s->free_packet_lists, link)
packet_list_free(packet_l, s);
if (s->packet_pool != NULL)
pci_pool_destroy(s->packet_pool);
s->current_packet_list = NULL;
INIT_LIST_HEAD(&s->free_packet_lists);
INIT_LIST_HEAD(&s->dma_packet_lists);
s->packet_pool = NULL;
}
static void plug_update(struct cmp_pcr *plug, void *data)
{
struct stream *s = data;
HPSB_INFO("plug update: p2p_count=%d, channel=%d",
plug->p2p_count, plug->channel);
s->iso_channel = plug->channel;
if (plug->p2p_count > 0) {
struct packet_list *pl;
pl = list_entry(s->dma_packet_lists.next, struct packet_list, link);
stream_start_dma(s, pl);
}
else {
ohci1394_stop_it_ctx(s->host->ohci, s->iso_tasklet.context, 0);
}
}
static int stream_configure(struct stream *s, int cmd, struct amdtp_ioctl *cfg)
{
const int transfer_delay = 9000;
if (cfg->format <= AMDTP_FORMAT_IEC958_AC3)
s->format = cfg->format;
else
return -EINVAL;
switch (cfg->rate) {
case 32000:
s->syt_interval = 8;
s->fdf = FDF_SFC_32KHZ;
s->iec958_rate_code = 0x0c;
break;
case 44100:
s->syt_interval = 8;
s->fdf = FDF_SFC_44K1HZ;
s->iec958_rate_code = 0x00;
break;
case 48000:
s->syt_interval = 8;
s->fdf = FDF_SFC_48KHZ;
s->iec958_rate_code = 0x04;
break;
case 88200:
s->syt_interval = 16;
s->fdf = FDF_SFC_88K2HZ;
s->iec958_rate_code = 0x00;
break;
case 96000:
s->syt_interval = 16;
s->fdf = FDF_SFC_96KHZ;
s->iec958_rate_code = 0x00;
break;
case 176400:
s->syt_interval = 32;
s->fdf = FDF_SFC_176K4HZ;
s->iec958_rate_code = 0x00;
break;
case 192000:
s->syt_interval = 32;
s->fdf = FDF_SFC_192KHZ;
s->iec958_rate_code = 0x00;
break;
default:
return -EINVAL;
}
s->rate = cfg->rate;
fraction_init(&s->samples_per_cycle, s->rate, 8000);
fraction_init(&s->ready_samples, 0, 8000);
/* The ticks_per_syt_offset is initialized to the number of
* ticks between syt_interval events. The number of ticks per
* second is 24.576e6, so the number of ticks between
* syt_interval events is 24.576e6 * syt_interval / rate.
*/
fraction_init(&s->ticks_per_syt_offset,
24576000 * s->syt_interval, s->rate);
fraction_init(&s->cycle_offset, (transfer_delay % 3072) * s->rate, s->rate);
atomic_set(&s->cycle_count, transfer_delay / 3072);
atomic_set(&s->cycle_count2, 0);
s->mode = cfg->mode;
s->sample_format = AMDTP_INPUT_LE16;
/* When using the AM824 raw subformat we can stream signals of
* any dimension. The IEC958 subformat, however, only
* supports 2 channels.
*/
if (s->format == AMDTP_FORMAT_RAW || cfg->dimension == 2)
s->dimension = cfg->dimension;
else
return -EINVAL;
if (s->opcr != NULL) {
cmp_unregister_opcr(s->host->host, s->opcr);
s->opcr = NULL;
}
switch(cmd) {
case AMDTP_IOC_PLUG:
s->opcr = cmp_register_opcr(s->host->host, cfg->u.plug,
/*payload*/ 12, plug_update, s);
if (s->opcr == NULL)
return -EINVAL;
s->iso_channel = s->opcr->channel;
break;
case AMDTP_IOC_CHANNEL:
if (cfg->u.channel >= 0 && cfg->u.channel < 64)
s->iso_channel = cfg->u.channel;
else
return -EINVAL;
break;
}
/* The ioctl settings were all valid, so we realloc the packet
* lists to make sure the packet size is big enough.
*/
if (s->packet_pool != NULL)
stream_free_packet_lists(s);
if (stream_alloc_packet_lists(s) < 0) {
stream_free_packet_lists(s);
return -ENOMEM;
}
return 0;
}
static struct stream *stream_alloc(struct amdtp_host *host)
{
struct stream *s;
unsigned long flags;
s = kmalloc(sizeof(struct stream), SLAB_KERNEL);
if (s == NULL)
return NULL;
memset(s, 0, sizeof(struct stream));
s->host = host;
s->input = buffer_alloc(BUFFER_SIZE);
if (s->input == NULL) {
kfree(s);
return NULL;
}
s->descriptor_pool = pci_pool_create("descriptor pool", host->ohci->dev,
sizeof(struct descriptor_block),
16, 0);
if (s->descriptor_pool == NULL) {
kfree(s->input);
kfree(s);
return NULL;
}
INIT_LIST_HEAD(&s->free_packet_lists);
INIT_LIST_HEAD(&s->dma_packet_lists);
init_waitqueue_head(&s->packet_list_wait);
spin_lock_init(&s->packet_list_lock);
ohci1394_init_iso_tasklet(&s->iso_tasklet, OHCI_ISO_TRANSMIT,
stream_shift_packet_lists,
(unsigned long) s);
if (ohci1394_register_iso_tasklet(host->ohci, &s->iso_tasklet) < 0) {
pci_pool_destroy(s->descriptor_pool);
kfree(s->input);
kfree(s);
return NULL;
}
spin_lock_irqsave(&host->stream_list_lock, flags);
list_add_tail(&s->link, &host->stream_list);
spin_unlock_irqrestore(&host->stream_list_lock, flags);
return s;
}
static void stream_free(struct stream *s)
{
unsigned long flags;
/* Stop the DMA. We wait for the dma packet list to become
* empty and let the dma controller run out of programs. This
* seems to be more reliable than stopping it directly, since
* that sometimes generates an it transmit interrupt if we
* later re-enable the context.
*/
wait_event_interruptible(s->packet_list_wait,
list_empty(&s->dma_packet_lists));
ohci1394_stop_it_ctx(s->host->ohci, s->iso_tasklet.context, 1);
ohci1394_unregister_iso_tasklet(s->host->ohci, &s->iso_tasklet);
if (s->opcr != NULL)
cmp_unregister_opcr(s->host->host, s->opcr);
spin_lock_irqsave(&s->host->stream_list_lock, flags);
list_del(&s->link);
spin_unlock_irqrestore(&s->host->stream_list_lock, flags);
kfree(s->input);
stream_free_packet_lists(s);
pci_pool_destroy(s->descriptor_pool);
kfree(s);
}
/* File operations */
static ssize_t amdtp_write(struct file *file, const char __user *buffer, size_t count,
loff_t *offset_is_ignored)
{
struct stream *s = file->private_data;
unsigned char *p;
int i;
size_t length;
if (s->packet_pool == NULL)
return -EBADFD;
/* Fill the circular buffer from the input buffer and call the
* iso packer when the buffer is full. The iso packer may
* leave bytes in the buffer for two reasons: either the
* remaining bytes wasn't enough to build a new packet, or
* there were no free packet lists. In the first case we
* re-fill the buffer and call the iso packer again or return
* if we used all the data from userspace. In the second
* case, the wait_event_interruptible will block until the irq
* handler frees a packet list.
*/
for (i = 0; i < count; i += length) {
p = buffer_put_bytes(s->input, count - i, &length);
if (copy_from_user(p, buffer + i, length))
return -EFAULT;
if (s->input->length < s->input->size)
continue;
stream_flush(s);
if (s->current_packet_list != NULL)
continue;
if (file->f_flags & O_NONBLOCK)
return i + length > 0 ? i + length : -EAGAIN;
if (wait_event_interruptible(s->packet_list_wait,
!list_empty(&s->free_packet_lists)))
return -EINTR;
}
return count;
}
static long amdtp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct stream *s = file->private_data;
struct amdtp_ioctl cfg;
int err;
lock_kernel();
switch(cmd)
{
case AMDTP_IOC_PLUG:
case AMDTP_IOC_CHANNEL:
if (copy_from_user(&cfg, (struct amdtp_ioctl __user *) arg, sizeof cfg))
err = -EFAULT;
else
err = stream_configure(s, cmd, &cfg);
break;
default:
err = -EINVAL;
break;
}
unlock_kernel();
return err;
}
static unsigned int amdtp_poll(struct file *file, poll_table *pt)
{
struct stream *s = file->private_data;
poll_wait(file, &s->packet_list_wait, pt);
if (!list_empty(&s->free_packet_lists))
return POLLOUT | POLLWRNORM;
else
return 0;
}
static int amdtp_open(struct inode *inode, struct file *file)
{
struct amdtp_host *host;
int i = ieee1394_file_to_instance(file);
host = hpsb_get_hostinfo_bykey(&amdtp_highlevel, i);
if (host == NULL)
return -ENODEV;
file->private_data = stream_alloc(host);
if (file->private_data == NULL)
return -ENOMEM;
return 0;
}
static int amdtp_release(struct inode *inode, struct file *file)
{
struct stream *s = file->private_data;
stream_free(s);
return 0;
}
static struct cdev amdtp_cdev;
static struct file_operations amdtp_fops =
{
.owner = THIS_MODULE,
.write = amdtp_write,
.poll = amdtp_poll,
.unlocked_ioctl = amdtp_ioctl,
.compat_ioctl = amdtp_ioctl, /* All amdtp ioctls are compatible */
.open = amdtp_open,
.release = amdtp_release
};
/* IEEE1394 Subsystem functions */
static void amdtp_add_host(struct hpsb_host *host)
{
struct amdtp_host *ah;
int minor;
if (strcmp(host->driver->name, OHCI1394_DRIVER_NAME) != 0)
return;
ah = hpsb_create_hostinfo(&amdtp_highlevel, host, sizeof(*ah));
if (!ah) {
HPSB_ERR("amdtp: Unable able to alloc hostinfo");
return;
}
ah->host = host;
ah->ohci = host->hostdata;
hpsb_set_hostinfo_key(&amdtp_highlevel, host, ah->host->id);
minor = IEEE1394_MINOR_BLOCK_AMDTP * 16 + ah->host->id;
INIT_LIST_HEAD(&ah->stream_list);
spin_lock_init(&ah->stream_list_lock);
devfs_mk_cdev(MKDEV(IEEE1394_MAJOR, minor),
S_IFCHR|S_IRUSR|S_IWUSR, "amdtp/%d", ah->host->id);
}
static void amdtp_remove_host(struct hpsb_host *host)
{
struct amdtp_host *ah = hpsb_get_hostinfo(&amdtp_highlevel, host);
if (ah)
devfs_remove("amdtp/%d", ah->host->id);
return;
}
static struct hpsb_highlevel amdtp_highlevel = {
.name = "amdtp",
.add_host = amdtp_add_host,
.remove_host = amdtp_remove_host,
};
/* Module interface */
MODULE_AUTHOR("Kristian Hogsberg <hogsberg@users.sf.net>");
MODULE_DESCRIPTION("Driver for Audio & Music Data Transmission Protocol "
"on OHCI boards.");
MODULE_SUPPORTED_DEVICE("amdtp");
MODULE_LICENSE("GPL");
static int __init amdtp_init_module (void)
{
cdev_init(&amdtp_cdev, &amdtp_fops);
amdtp_cdev.owner = THIS_MODULE;
kobject_set_name(&amdtp_cdev.kobj, "amdtp");
if (cdev_add(&amdtp_cdev, IEEE1394_AMDTP_DEV, 16)) {
HPSB_ERR("amdtp: unable to add char device");
return -EIO;
}
devfs_mk_dir("amdtp");
hpsb_register_highlevel(&amdtp_highlevel);
HPSB_INFO("Loaded AMDTP driver");
return 0;
}
static void __exit amdtp_exit_module (void)
{
hpsb_unregister_highlevel(&amdtp_highlevel);
devfs_remove("amdtp");
cdev_del(&amdtp_cdev);
HPSB_INFO("Unloaded AMDTP driver");
}
module_init(amdtp_init_module);
module_exit(amdtp_exit_module);
