linux-stable/sound/firewire/tascam/amdtp-tascam.c
Takashi Sakamoto 747d1f076d ALSA: firewire-tascam: fix corruption due to spin lock without restoration in SoftIRQ context
ALSA firewire-tascam driver can bring corruption due to spin lock without
restoration of IRQ flag in SoftIRQ context. This commit fixes the bug.

Cc: Scott Bahling <sbahling@suse.com>
Cc: <stable@vger.kernel.org> # v4.21
Fixes: d716742243 ("ALSA: firewire-tascam: queue events for change of control surface")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20200113085719.26788-1-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2020-01-13 10:41:01 +01:00

261 lines
6.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* amdtp-tascam.c - a part of driver for TASCAM FireWire series
*
* Copyright (c) 2015 Takashi Sakamoto
*/
#include <sound/pcm.h>
#include "tascam.h"
#define AMDTP_FMT_TSCM_TX 0x1e
#define AMDTP_FMT_TSCM_RX 0x3e
struct amdtp_tscm {
unsigned int pcm_channels;
};
int amdtp_tscm_set_parameters(struct amdtp_stream *s, unsigned int rate)
{
struct amdtp_tscm *p = s->protocol;
unsigned int data_channels;
if (amdtp_stream_running(s))
return -EBUSY;
data_channels = p->pcm_channels;
/* Packets in in-stream have extra 2 data channels. */
if (s->direction == AMDTP_IN_STREAM)
data_channels += 2;
return amdtp_stream_set_parameters(s, rate, data_channels);
}
static void write_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames,
unsigned int pcm_frames)
{
struct amdtp_tscm *p = s->protocol;
unsigned int channels = p->pcm_channels;
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int pcm_buffer_pointer;
int remaining_frames;
const u32 *src;
int i, c;
pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
pcm_buffer_pointer %= runtime->buffer_size;
src = (void *)runtime->dma_area +
frames_to_bytes(runtime, pcm_buffer_pointer);
remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
buffer[c] = cpu_to_be32(*src);
src++;
}
buffer += s->data_block_quadlets;
if (--remaining_frames == 0)
src = (void *)runtime->dma_area;
}
}
static void read_pcm_s32(struct amdtp_stream *s, struct snd_pcm_substream *pcm,
__be32 *buffer, unsigned int frames,
unsigned int pcm_frames)
{
struct amdtp_tscm *p = s->protocol;
unsigned int channels = p->pcm_channels;
struct snd_pcm_runtime *runtime = pcm->runtime;
unsigned int pcm_buffer_pointer;
int remaining_frames;
u32 *dst;
int i, c;
pcm_buffer_pointer = s->pcm_buffer_pointer + pcm_frames;
pcm_buffer_pointer %= runtime->buffer_size;
dst = (void *)runtime->dma_area +
frames_to_bytes(runtime, pcm_buffer_pointer);
remaining_frames = runtime->buffer_size - pcm_buffer_pointer;
/* The first data channel is for event counter. */
buffer += 1;
for (i = 0; i < frames; ++i) {
for (c = 0; c < channels; ++c) {
*dst = be32_to_cpu(buffer[c]);
dst++;
}
buffer += s->data_block_quadlets;
if (--remaining_frames == 0)
dst = (void *)runtime->dma_area;
}
}
static void write_pcm_silence(struct amdtp_stream *s, __be32 *buffer,
unsigned int data_blocks)
{
struct amdtp_tscm *p = s->protocol;
unsigned int channels, i, c;
channels = p->pcm_channels;
for (i = 0; i < data_blocks; ++i) {
for (c = 0; c < channels; ++c)
buffer[c] = 0x00000000;
buffer += s->data_block_quadlets;
}
}
int amdtp_tscm_add_pcm_hw_constraints(struct amdtp_stream *s,
struct snd_pcm_runtime *runtime)
{
int err;
/*
* Our implementation allows this protocol to deliver 24 bit sample in
* 32bit data channel.
*/
err = snd_pcm_hw_constraint_msbits(runtime, 0, 32, 24);
if (err < 0)
return err;
return amdtp_stream_add_pcm_hw_constraints(s, runtime);
}
static void read_status_messages(struct amdtp_stream *s,
__be32 *buffer, unsigned int data_blocks)
{
struct snd_tscm *tscm = container_of(s, struct snd_tscm, tx_stream);
bool used = READ_ONCE(tscm->hwdep->used);
int i;
for (i = 0; i < data_blocks; i++) {
unsigned int index;
__be32 before;
__be32 after;
index = be32_to_cpu(buffer[0]) % SNDRV_FIREWIRE_TASCAM_STATE_COUNT;
before = tscm->state[index];
after = buffer[s->data_block_quadlets - 1];
if (used && index > 4 && index < 16) {
__be32 mask;
if (index == 5)
mask = cpu_to_be32(~0x0000ffff);
else if (index == 6)
mask = cpu_to_be32(~0x0000ffff);
else if (index == 8)
mask = cpu_to_be32(~0x000f0f00);
else
mask = cpu_to_be32(~0x00000000);
if ((before ^ after) & mask) {
struct snd_firewire_tascam_change *entry =
&tscm->queue[tscm->push_pos];
unsigned long flag;
spin_lock_irqsave(&tscm->lock, flag);
entry->index = index;
entry->before = before;
entry->after = after;
if (++tscm->push_pos >= SND_TSCM_QUEUE_COUNT)
tscm->push_pos = 0;
spin_unlock_irqrestore(&tscm->lock, flag);
wake_up(&tscm->hwdep_wait);
}
}
tscm->state[index] = after;
buffer += s->data_block_quadlets;
}
}
static unsigned int process_ir_ctx_payloads(struct amdtp_stream *s,
const struct pkt_desc *descs,
unsigned int packets,
struct snd_pcm_substream *pcm)
{
unsigned int pcm_frames = 0;
int i;
for (i = 0; i < packets; ++i) {
const struct pkt_desc *desc = descs + i;
__be32 *buf = desc->ctx_payload;
unsigned int data_blocks = desc->data_blocks;
if (pcm) {
read_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
pcm_frames += data_blocks;
}
read_status_messages(s, buf, data_blocks);
}
return pcm_frames;
}
static unsigned int process_it_ctx_payloads(struct amdtp_stream *s,
const struct pkt_desc *descs,
unsigned int packets,
struct snd_pcm_substream *pcm)
{
unsigned int pcm_frames = 0;
int i;
for (i = 0; i < packets; ++i) {
const struct pkt_desc *desc = descs + i;
__be32 *buf = desc->ctx_payload;
unsigned int data_blocks = desc->data_blocks;
if (pcm) {
write_pcm_s32(s, pcm, buf, data_blocks, pcm_frames);
pcm_frames += data_blocks;
} else {
write_pcm_silence(s, buf, data_blocks);
}
}
return pcm_frames;
}
int amdtp_tscm_init(struct amdtp_stream *s, struct fw_unit *unit,
enum amdtp_stream_direction dir, unsigned int pcm_channels)
{
amdtp_stream_process_ctx_payloads_t process_ctx_payloads;
struct amdtp_tscm *p;
unsigned int fmt;
int err;
if (dir == AMDTP_IN_STREAM) {
fmt = AMDTP_FMT_TSCM_TX;
process_ctx_payloads = process_ir_ctx_payloads;
} else {
fmt = AMDTP_FMT_TSCM_RX;
process_ctx_payloads = process_it_ctx_payloads;
}
err = amdtp_stream_init(s, unit, dir,
CIP_NONBLOCKING | CIP_SKIP_DBC_ZERO_CHECK, fmt,
process_ctx_payloads, sizeof(struct amdtp_tscm));
if (err < 0)
return 0;
if (dir == AMDTP_OUT_STREAM) {
// Use fixed value for FDF field.
s->ctx_data.rx.fdf = 0x00;
// Not used.
s->ctx_data.rx.syt_override = 0x0000;
}
/* This protocol uses fixed number of data channels for PCM samples. */
p = s->protocol;
p->pcm_channels = pcm_channels;
return 0;
}