usb_stream.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2007, 2008 Karsten Wiese <fzu@wemgehoertderstaat.de>
*/
#include <linux/usb.h>
#include <linux/gfp.h>
#include "usb_stream.h"
/* setup */
static unsigned usb_stream_next_packet_size(struct usb_stream_kernel *sk)
{
struct usb_stream *s = sk->s;
sk->out_phase_peeked = (sk->out_phase & 0xffff) + sk->freqn;
return (sk->out_phase_peeked >> 16) * s->cfg.frame_size;
}
static void playback_prep_freqn(struct usb_stream_kernel *sk, struct urb *urb)
{
struct usb_stream *s = sk->s;
int pack, lb = 0;
for (pack = 0; pack < sk->n_o_ps; pack++) {
int l = usb_stream_next_packet_size(sk);
if (s->idle_outsize + lb + l > s->period_size)
goto check;
sk->out_phase = sk->out_phase_peeked;
urb->iso_frame_desc[pack].offset = lb;
urb->iso_frame_desc[pack].length = l;
lb += l;
}
snd_printdd(KERN_DEBUG "%i\n", lb);
check:
urb->number_of_packets = pack;
urb->transfer_buffer_length = lb;
s->idle_outsize += lb - s->period_size;
snd_printdd(KERN_DEBUG "idle=%i ul=%i ps=%i\n", s->idle_outsize,
lb, s->period_size);
}
static int init_pipe_urbs(struct usb_stream_kernel *sk, unsigned use_packsize,
struct urb **urbs, char *transfer,
struct usb_device *dev, int pipe)
{
int u, p;
int maxpacket = use_packsize ?
use_packsize : usb_maxpacket(dev, pipe, usb_pipeout(pipe));
int transfer_length = maxpacket * sk->n_o_ps;
for (u = 0; u < USB_STREAM_NURBS;
++u, transfer += transfer_length) {
struct urb *urb = urbs[u];
struct usb_iso_packet_descriptor *desc;
urb->transfer_buffer = transfer;
urb->dev = dev;
urb->pipe = pipe;
urb->number_of_packets = sk->n_o_ps;
urb->context = sk;
urb->interval = 1;
if (usb_pipeout(pipe))
continue;
if (usb_urb_ep_type_check(urb))
return -EINVAL;
urb->transfer_buffer_length = transfer_length;
desc = urb->iso_frame_desc;
desc->offset = 0;
desc->length = maxpacket;
for (p = 1; p < sk->n_o_ps; ++p) {
desc[p].offset = desc[p - 1].offset + maxpacket;
desc[p].length = maxpacket;
}
}
return 0;
}
static int init_urbs(struct usb_stream_kernel *sk, unsigned use_packsize,
struct usb_device *dev, int in_pipe, int out_pipe)
{
struct usb_stream *s = sk->s;
char *indata = (char *)s + sizeof(*s) +
sizeof(struct usb_stream_packet) *
s->inpackets;
int u;
for (u = 0; u < USB_STREAM_NURBS; ++u) {
sk->inurb[u] = usb_alloc_urb(sk->n_o_ps, GFP_KERNEL);
if (!sk->inurb[u])
return -ENOMEM;
sk->outurb[u] = usb_alloc_urb(sk->n_o_ps, GFP_KERNEL);
if (!sk->outurb[u])
return -ENOMEM;
}
if (init_pipe_urbs(sk, use_packsize, sk->inurb, indata, dev, in_pipe) ||
init_pipe_urbs(sk, use_packsize, sk->outurb, sk->write_page, dev,
out_pipe))
return -EINVAL;
return 0;
}
/*
* convert a sampling rate into our full speed format (fs/1000 in Q16.16)
* this will overflow at approx 524 kHz
*/
static inline unsigned get_usb_full_speed_rate(unsigned rate)
{
return ((rate << 13) + 62) / 125;
}
/*
* convert a sampling rate into USB high speed format (fs/8000 in Q16.16)
* this will overflow at approx 4 MHz
*/
static inline unsigned get_usb_high_speed_rate(unsigned rate)
{
return ((rate << 10) + 62) / 125;
}
void usb_stream_free(struct usb_stream_kernel *sk)
{
struct usb_stream *s;
unsigned u;
for (u = 0; u < USB_STREAM_NURBS; ++u) {
usb_free_urb(sk->inurb[u]);
sk->inurb[u] = NULL;
usb_free_urb(sk->outurb[u]);
sk->outurb[u] = NULL;
}
s = sk->s;
if (!s)
return;
free_pages_exact(sk->write_page, s->write_size);
sk->write_page = NULL;
free_pages_exact(s, s->read_size);
sk->s = NULL;
}
struct usb_stream *usb_stream_new(struct usb_stream_kernel *sk,
struct usb_device *dev,
unsigned in_endpoint, unsigned out_endpoint,
unsigned sample_rate, unsigned use_packsize,
unsigned period_frames, unsigned frame_size)
{
int packets, max_packsize;
int in_pipe, out_pipe;
int read_size = sizeof(struct usb_stream);
int write_size;
int usb_frames = dev->speed == USB_SPEED_HIGH ? 8000 : 1000;
in_pipe = usb_rcvisocpipe(dev, in_endpoint);
out_pipe = usb_sndisocpipe(dev, out_endpoint);
max_packsize = use_packsize ?
use_packsize : usb_maxpacket(dev, in_pipe, 0);
/*
t_period = period_frames / sample_rate
iso_packs = t_period / t_iso_frame
= (period_frames / sample_rate) * (1 / t_iso_frame)
*/
packets = period_frames * usb_frames / sample_rate + 1;
if (dev->speed == USB_SPEED_HIGH)
packets = (packets + 7) & ~7;
read_size += packets * USB_STREAM_URBDEPTH *
(max_packsize + sizeof(struct usb_stream_packet));
max_packsize = usb_maxpacket(dev, out_pipe, 1);
write_size = max_packsize * packets * USB_STREAM_URBDEPTH;
if (read_size >= 256*PAGE_SIZE || write_size >= 256*PAGE_SIZE) {
snd_printk(KERN_WARNING "a size exceeds 128*PAGE_SIZE\n");
goto out;
}
sk->s = alloc_pages_exact(read_size,
GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN);
if (!sk->s) {
pr_warn("us122l: couldn't allocate read buffer\n");
goto out;
}
sk->s->cfg.version = USB_STREAM_INTERFACE_VERSION;
sk->s->read_size = read_size;
sk->s->cfg.sample_rate = sample_rate;
sk->s->cfg.frame_size = frame_size;
sk->n_o_ps = packets;
sk->s->inpackets = packets * USB_STREAM_URBDEPTH;
sk->s->cfg.period_frames = period_frames;
sk->s->period_size = frame_size * period_frames;
sk->s->write_size = write_size;
sk->write_page = alloc_pages_exact(write_size,
GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN);
if (!sk->write_page) {
pr_warn("us122l: couldn't allocate write buffer\n");
usb_stream_free(sk);
return NULL;
}
/* calculate the frequency in 16.16 format */
if (dev->speed == USB_SPEED_FULL)
sk->freqn = get_usb_full_speed_rate(sample_rate);
else
sk->freqn = get_usb_high_speed_rate(sample_rate);
if (init_urbs(sk, use_packsize, dev, in_pipe, out_pipe) < 0) {
usb_stream_free(sk);
return NULL;
}
sk->s->state = usb_stream_stopped;
out:
return sk->s;
}
/* start */
static bool balance_check(struct usb_stream_kernel *sk, struct urb *urb)
{
bool r;
if (unlikely(urb->status)) {
if (urb->status != -ESHUTDOWN && urb->status != -ENOENT)
snd_printk(KERN_WARNING "status=%i\n", urb->status);
sk->iso_frame_balance = 0x7FFFFFFF;
return false;
}
r = sk->iso_frame_balance == 0;
if (!r)
sk->i_urb = urb;
return r;
}
static bool balance_playback(struct usb_stream_kernel *sk, struct urb *urb)
{
sk->iso_frame_balance += urb->number_of_packets;
return balance_check(sk, urb);
}
static bool balance_capture(struct usb_stream_kernel *sk, struct urb *urb)
{
sk->iso_frame_balance -= urb->number_of_packets;
return balance_check(sk, urb);
}
static void subs_set_complete(struct urb **urbs, void (*complete)(struct urb *))
{
int u;
for (u = 0; u < USB_STREAM_NURBS; u++) {
struct urb *urb = urbs[u];
urb->complete = complete;
}
}
static int usb_stream_prepare_playback(struct usb_stream_kernel *sk,
struct urb *inurb)
{
struct usb_stream *s = sk->s;
struct urb *io;
struct usb_iso_packet_descriptor *id, *od;
int p = 0, lb = 0, l = 0;
io = sk->idle_outurb;
od = io->iso_frame_desc;
for (; s->sync_packet < 0; ++p, ++s->sync_packet) {
struct urb *ii = sk->completed_inurb;
id = ii->iso_frame_desc +
ii->number_of_packets + s->sync_packet;
l = id->actual_length;
od[p].length = l;
od[p].offset = lb;
lb += l;
}
for (;
s->sync_packet < inurb->number_of_packets && p < sk->n_o_ps;
++p, ++s->sync_packet) {
l = inurb->iso_frame_desc[s->sync_packet].actual_length;
if (s->idle_outsize + lb + l > s->period_size)
goto check_ok;
od[p].length = l;
od[p].offset = lb;
lb += l;
}
check_ok:
s->sync_packet -= inurb->number_of_packets;
if (unlikely(s->sync_packet < -2 || s->sync_packet > 0)) {
snd_printk(KERN_WARNING "invalid sync_packet = %i;"
" p=%i nop=%i %i %x %x %x > %x\n",
s->sync_packet, p, inurb->number_of_packets,
s->idle_outsize + lb + l,
s->idle_outsize, lb, l,
s->period_size);
return -1;
}
if (unlikely(lb % s->cfg.frame_size)) {
snd_printk(KERN_WARNING"invalid outsize = %i\n",
lb);
return -1;
}
s->idle_outsize += lb - s->period_size;
io->number_of_packets = p;
io->transfer_buffer_length = lb;
if (s->idle_outsize <= 0)
return 0;
snd_printk(KERN_WARNING "idle=%i\n", s->idle_outsize);
return -1;
}
static void prepare_inurb(int number_of_packets, struct urb *iu)
{
struct usb_iso_packet_descriptor *id;
int p;
iu->number_of_packets = number_of_packets;
id = iu->iso_frame_desc;
id->offset = 0;
for (p = 0; p < iu->number_of_packets - 1; ++p)
id[p + 1].offset = id[p].offset + id[p].length;
iu->transfer_buffer_length =
id[0].length * iu->number_of_packets;
}
static int submit_urbs(struct usb_stream_kernel *sk,
struct urb *inurb, struct urb *outurb)
{
int err;
prepare_inurb(sk->idle_outurb->number_of_packets, sk->idle_inurb);
err = usb_submit_urb(sk->idle_inurb, GFP_ATOMIC);
if (err < 0)
goto report_failure;
sk->idle_inurb = sk->completed_inurb;
sk->completed_inurb = inurb;
err = usb_submit_urb(sk->idle_outurb, GFP_ATOMIC);
if (err < 0)
goto report_failure;
sk->idle_outurb = sk->completed_outurb;
sk->completed_outurb = outurb;
return 0;
report_failure:
snd_printk(KERN_ERR "%i\n", err);
return err;
}
#ifdef DEBUG_LOOP_BACK
/*
This loop_back() shows how to read/write the period data.
*/
static void loop_back(struct usb_stream *s)
{
char *i, *o;
int il, ol, l, p;
struct urb *iu;
struct usb_iso_packet_descriptor *id;
o = s->playback1st_to;
ol = s->playback1st_size;
l = 0;
if (s->insplit_pack >= 0) {
iu = sk->idle_inurb;
id = iu->iso_frame_desc;
p = s->insplit_pack;
} else
goto second;
loop:
for (; p < iu->number_of_packets && l < s->period_size; ++p) {
i = iu->transfer_buffer + id[p].offset;
il = id[p].actual_length;
if (l + il > s->period_size)
il = s->period_size - l;
if (il <= ol) {
memcpy(o, i, il);
o += il;
ol -= il;
} else {
memcpy(o, i, ol);
singen_6pack(o, ol);
o = s->playback_to;
memcpy(o, i + ol, il - ol);
o += il - ol;
ol = s->period_size - s->playback1st_size;
}
l += il;
}
if (iu == sk->completed_inurb) {
if (l != s->period_size)
printk(KERN_DEBUG"%s:%i %i\n", __func__, __LINE__,
l/(int)s->cfg.frame_size);
return;
}
second:
iu = sk->completed_inurb;
id = iu->iso_frame_desc;
p = 0;
goto loop;
}
#else
static void loop_back(struct usb_stream *s)
{
}
#endif
static void stream_idle(struct usb_stream_kernel *sk,
struct urb *inurb, struct urb *outurb)
{
struct usb_stream *s = sk->s;
int l, p;
int insize = s->idle_insize;
int urb_size = 0;
s->inpacket_split = s->next_inpacket_split;
s->inpacket_split_at = s->next_inpacket_split_at;
s->next_inpacket_split = -1;
s->next_inpacket_split_at = 0;
for (p = 0; p < inurb->number_of_packets; ++p) {
struct usb_iso_packet_descriptor *id = inurb->iso_frame_desc;
l = id[p].actual_length;
if (unlikely(l == 0 || id[p].status)) {
snd_printk(KERN_WARNING "underrun, status=%u\n",
id[p].status);
goto err_out;
}
s->inpacket_head++;
s->inpacket_head %= s->inpackets;
if (s->inpacket_split == -1)
s->inpacket_split = s->inpacket_head;
s->inpacket[s->inpacket_head].offset =
id[p].offset + (inurb->transfer_buffer - (void *)s);
s->inpacket[s->inpacket_head].length = l;
if (insize + l > s->period_size &&
s->next_inpacket_split == -1) {
s->next_inpacket_split = s->inpacket_head;
s->next_inpacket_split_at = s->period_size - insize;
}
insize += l;
urb_size += l;
}
s->idle_insize += urb_size - s->period_size;
if (s->idle_insize < 0) {
snd_printk(KERN_WARNING "%i\n",
(s->idle_insize)/(int)s->cfg.frame_size);
goto err_out;
}
s->insize_done += urb_size;
l = s->idle_outsize;
s->outpacket[0].offset = (sk->idle_outurb->transfer_buffer -
sk->write_page) - l;
if (usb_stream_prepare_playback(sk, inurb) < 0)
goto err_out;
s->outpacket[0].length = sk->idle_outurb->transfer_buffer_length + l;
s->outpacket[1].offset = sk->completed_outurb->transfer_buffer -
sk->write_page;
if (submit_urbs(sk, inurb, outurb) < 0)
goto err_out;
loop_back(s);
s->periods_done++;
wake_up_all(&sk->sleep);
return;
err_out:
s->state = usb_stream_xrun;
wake_up_all(&sk->sleep);
}
static void i_capture_idle(struct urb *urb)
{
struct usb_stream_kernel *sk = urb->context;
if (balance_capture(sk, urb))
stream_idle(sk, urb, sk->i_urb);
}
static void i_playback_idle(struct urb *urb)
{
struct usb_stream_kernel *sk = urb->context;
if (balance_playback(sk, urb))
stream_idle(sk, sk->i_urb, urb);
}
static void stream_start(struct usb_stream_kernel *sk,
struct urb *inurb, struct urb *outurb)
{
struct usb_stream *s = sk->s;
if (s->state >= usb_stream_sync1) {
int l, p, max_diff, max_diff_0;
int urb_size = 0;
unsigned frames_per_packet, min_frames = 0;
frames_per_packet = (s->period_size - s->idle_insize);
frames_per_packet <<= 8;
frames_per_packet /=
s->cfg.frame_size * inurb->number_of_packets;
frames_per_packet++;
max_diff_0 = s->cfg.frame_size;
if (s->cfg.period_frames >= 256)
max_diff_0 <<= 1;
if (s->cfg.period_frames >= 1024)
max_diff_0 <<= 1;
max_diff = max_diff_0;
for (p = 0; p < inurb->number_of_packets; ++p) {
int diff;
l = inurb->iso_frame_desc[p].actual_length;
urb_size += l;
min_frames += frames_per_packet;
diff = urb_size -
(min_frames >> 8) * s->cfg.frame_size;
if (diff < max_diff) {
snd_printdd(KERN_DEBUG "%i %i %i %i\n",
s->insize_done,
urb_size / (int)s->cfg.frame_size,
inurb->number_of_packets, diff);
max_diff = diff;
}
}
s->idle_insize -= max_diff - max_diff_0;
s->idle_insize += urb_size - s->period_size;
if (s->idle_insize < 0) {
snd_printk(KERN_WARNING "%i %i %i\n",
s->idle_insize, urb_size, s->period_size);
return;
} else if (s->idle_insize == 0) {
s->next_inpacket_split =
(s->inpacket_head + 1) % s->inpackets;
s->next_inpacket_split_at = 0;
} else {
unsigned split = s->inpacket_head;
l = s->idle_insize;
while (l > s->inpacket[split].length) {
l -= s->inpacket[split].length;
if (split == 0)
split = s->inpackets - 1;
else
split--;
}
s->next_inpacket_split = split;
s->next_inpacket_split_at =
s->inpacket[split].length - l;
}
s->insize_done += urb_size;
if (usb_stream_prepare_playback(sk, inurb) < 0)
return;
} else
playback_prep_freqn(sk, sk->idle_outurb);
if (submit_urbs(sk, inurb, outurb) < 0)
return;
if (s->state == usb_stream_sync1 && s->insize_done > 360000) {
/* just guesswork ^^^^^^ */
s->state = usb_stream_ready;
subs_set_complete(sk->inurb, i_capture_idle);
subs_set_complete(sk->outurb, i_playback_idle);
}
}
static void i_capture_start(struct urb *urb)
{
struct usb_iso_packet_descriptor *id = urb->iso_frame_desc;
struct usb_stream_kernel *sk = urb->context;
struct usb_stream *s = sk->s;
int p;
int empty = 0;
if (urb->status) {
snd_printk(KERN_WARNING "status=%i\n", urb->status);
return;
}
for (p = 0; p < urb->number_of_packets; ++p) {
int l = id[p].actual_length;
if (l < s->cfg.frame_size) {
++empty;
if (s->state >= usb_stream_sync0) {
snd_printk(KERN_WARNING "%i\n", l);
return;
}
}
s->inpacket_head++;
s->inpacket_head %= s->inpackets;
s->inpacket[s->inpacket_head].offset =
id[p].offset + (urb->transfer_buffer - (void *)s);
s->inpacket[s->inpacket_head].length = l;
}
#ifdef SHOW_EMPTY
if (empty) {
printk(KERN_DEBUG"%s:%i: %i", __func__, __LINE__,
urb->iso_frame_desc[0].actual_length);
for (pack = 1; pack < urb->number_of_packets; ++pack) {
int l = urb->iso_frame_desc[pack].actual_length;
printk(KERN_CONT " %i", l);
}
printk(KERN_CONT "\n");
}
#endif
if (!empty && s->state < usb_stream_sync1)
++s->state;
if (balance_capture(sk, urb))
stream_start(sk, urb, sk->i_urb);
}
static void i_playback_start(struct urb *urb)
{
struct usb_stream_kernel *sk = urb->context;
if (balance_playback(sk, urb))
stream_start(sk, sk->i_urb, urb);
}
int usb_stream_start(struct usb_stream_kernel *sk)
{
struct usb_stream *s = sk->s;
int frame = 0, iters = 0;
int u, err;
int try = 0;
if (s->state != usb_stream_stopped)
return -EAGAIN;
subs_set_complete(sk->inurb, i_capture_start);
subs_set_complete(sk->outurb, i_playback_start);
memset(sk->write_page, 0, s->write_size);
dotry:
s->insize_done = 0;
s->idle_insize = 0;
s->idle_outsize = 0;
s->sync_packet = -1;
s->inpacket_head = -1;
sk->iso_frame_balance = 0;
++try;
for (u = 0; u < 2; u++) {
struct urb *inurb = sk->inurb[u];
struct urb *outurb = sk->outurb[u];
playback_prep_freqn(sk, outurb);
inurb->number_of_packets = outurb->number_of_packets;
inurb->transfer_buffer_length =
inurb->number_of_packets *
inurb->iso_frame_desc[0].length;
if (u == 0) {
int now;
struct usb_device *dev = inurb->dev;
frame = usb_get_current_frame_number(dev);
do {
now = usb_get_current_frame_number(dev);
++iters;
} while (now > -1 && now == frame);
}
err = usb_submit_urb(inurb, GFP_ATOMIC);
if (err < 0) {
snd_printk(KERN_ERR"usb_submit_urb(sk->inurb[%i])"
" returned %i\n", u, err);
return err;
}
err = usb_submit_urb(outurb, GFP_ATOMIC);
if (err < 0) {
snd_printk(KERN_ERR"usb_submit_urb(sk->outurb[%i])"
" returned %i\n", u, err);
return err;
}
if (inurb->start_frame != outurb->start_frame) {
snd_printd(KERN_DEBUG
"u[%i] start_frames differ in:%u out:%u\n",
u, inurb->start_frame, outurb->start_frame);
goto check_retry;
}
}
snd_printdd(KERN_DEBUG "%i %i\n", frame, iters);
try = 0;
check_retry:
if (try) {
usb_stream_stop(sk);
if (try < 5) {
msleep(1500);
snd_printd(KERN_DEBUG "goto dotry;\n");
goto dotry;
}
snd_printk(KERN_WARNING"couldn't start"
" all urbs on the same start_frame.\n");
return -EFAULT;
}
sk->idle_inurb = sk->inurb[USB_STREAM_NURBS - 2];
sk->idle_outurb = sk->outurb[USB_STREAM_NURBS - 2];
sk->completed_inurb = sk->inurb[USB_STREAM_NURBS - 1];
sk->completed_outurb = sk->outurb[USB_STREAM_NURBS - 1];
/* wait, check */
{
int wait_ms = 3000;
while (s->state != usb_stream_ready && wait_ms > 0) {
snd_printdd(KERN_DEBUG "%i\n", s->state);
msleep(200);
wait_ms -= 200;
}
}
return s->state == usb_stream_ready ? 0 : -EFAULT;
}
/* stop */
void usb_stream_stop(struct usb_stream_kernel *sk)
{
int u;
if (!sk->s)
return;
for (u = 0; u < USB_STREAM_NURBS; ++u) {
usb_kill_urb(sk->inurb[u]);
usb_kill_urb(sk->outurb[u]);
}
sk->s->state = usb_stream_stopped;
msleep(400);
}