Re: [alsa-devel] [PATCH] ALSA AICA sound on SEGA Dreamcast - fix behaviour in poor resource conditions
From: Adrian McMenamin
Date: Fri Jul 06 2007 - 16:42:41 EST
On 06/07/07, Adrian McMenamin <adrianmcmenamin@xxxxxxxxx> wrote:
On 06/07/07, Takashi Iwai <tiwai@xxxxxxx> wrote:
> I guess you shoud call del_timer() there at least. Otherwise the
> timer handler (aica_period_elapsed()) might be called even if the
> stream is not really running.
>
Fair enough. I'll fix that and repost later.
Attached is a new patch, tidied with indent and with
SNDRV_PCM_TRIGGER_STOP being used.
Submitted by: Adrian McMenamin <adrian@xxxxxxxxxxxxxxxxx>
Signed-off by: Adrian McMenamin <adrian@xxxxxxxxxxxxxxxxx>
diff -ruN aicaold/aica.c aicanew/aica.c
--- aicaold/aica.c 2007-07-05 23:01:39.000000000 +0100
+++ aicanew/aica.c 2007-07-06 21:36:55.000000000 +0100
@@ -64,12 +64,6 @@
MODULE_PARM_DESC(enable, "Enable " CARD_NAME " soundcard.");
/* Use workqueue */
-
-static struct spu_work_holder {
- struct work_struct spu_dma_work;
- void *sspointer;
-} spu_working;
-
static struct workqueue_struct *aica_queue;
/* Simple platform device */
@@ -100,9 +94,9 @@
break;
/* To ensure hardware failure doesn't wedge kernel */
time_count++;
- if (time_count > 0x10000)
- {
- snd_printk("WARNING: G2 FIFO appears to be blocked.\n");
+ if (time_count > 0x10000) {
+ snd_printk
+ ("WARNING: G2 FIFO appears to be blocked.\n");
break;
}
}
@@ -226,11 +220,11 @@
runtime = substream->runtime;
for (q = 0; q < channels; q++) {
err = dma_xfer(AICA_DMA_CHANNEL,
- (unsigned long)(runtime->dma_area +
- (AICA_BUFFER_SIZE * q) /
- channels +
- AICA_PERIOD_SIZE *
- period_offset),
+ (unsigned long) (runtime->dma_area +
+ (AICA_BUFFER_SIZE * q) /
+ channels +
+ AICA_PERIOD_SIZE *
+ period_offset),
AICA_CHANNEL0_OFFSET + q * CHANNEL_OFFSET +
AICA_PERIOD_SIZE * period_offset,
buffer_size / channels, AICA_DMA_MODE);
@@ -244,26 +238,25 @@
static void startup_aica(struct snd_card_aica *dreamcastcard)
{
spu_memload(AICA_CHANNEL0_CONTROL_OFFSET,
- dreamcastcard->channel,
- sizeof(struct aica_channel));
+ dreamcastcard->channel, sizeof(struct aica_channel));
aica_chn_start();
}
static void run_spu_dma(struct work_struct *work)
{
int buffer_size;
- struct snd_pcm_substream *substream;
struct snd_pcm_runtime *runtime;
struct snd_card_aica *dreamcastcard;
- struct spu_work_holder *holder = container_of(work, struct spu_work_holder, spu_dma_work);
- substream = holder-> sspointer;
- dreamcastcard = substream->pcm->private_data;
- runtime = substream->runtime;
+ dreamcastcard =
+ container_of(work, struct snd_card_aica, spu_dma_work);
+ runtime = dreamcastcard->substream->runtime;
if (unlikely(dreamcastcard->dma_check == 0)) {
- buffer_size = frames_to_bytes(runtime, runtime->buffer_size);
+ buffer_size =
+ frames_to_bytes(runtime, runtime->buffer_size);
if (runtime->channels > 1)
dreamcastcard->channel->flags |= 0x01;
- aica_dma_transfer(runtime->channels, buffer_size, substream);
+ aica_dma_transfer(runtime->channels, buffer_size,
+ dreamcastcard->substream);
startup_aica(dreamcastcard);
dreamcastcard->clicks =
buffer_size / (AICA_PERIOD_SIZE * runtime->channels);
@@ -271,13 +264,11 @@
} else {
aica_dma_transfer(runtime->channels,
AICA_PERIOD_SIZE * runtime->channels,
- substream);
+ dreamcastcard->substream);
snd_pcm_period_elapsed(dreamcastcard->substream);
dreamcastcard->clicks++;
if (unlikely(dreamcastcard->clicks >= AICA_PERIOD_NUMBER))
- {
dreamcastcard->clicks %= AICA_PERIOD_NUMBER;
- }
mod_timer(&dreamcastcard->timer, jiffies + 1);
}
}
@@ -289,7 +280,7 @@
struct snd_pcm_runtime *runtime;
struct snd_pcm_substream *substream;
struct snd_card_aica *dreamcastcard;
- substream = (struct snd_pcm_substream *)timer_var;
+ substream = (struct snd_pcm_substream *) timer_var;
runtime = substream->runtime;
dreamcastcard = substream->pcm->private_data;
/* Have we played out an additional period? */
@@ -307,27 +298,24 @@
dreamcastcard->current_period = play_period;
if (unlikely(dreamcastcard->dma_check == 0))
dreamcastcard->dma_check = 1;
- queue_work(aica_queue, &(spu_working.spu_dma_work));
+ queue_work(aica_queue, &(dreamcastcard->spu_dma_work));
}
static void spu_begin_dma(struct snd_pcm_substream *substream)
{
- /* Must be atomic */
struct snd_card_aica *dreamcastcard;
struct snd_pcm_runtime *runtime;
runtime = substream->runtime;
dreamcastcard = substream->pcm->private_data;
- /* Use queue to do the heavy lifting */
- spu_working.sspointer = substream;
- INIT_WORK(&(spu_working.spu_dma_work), run_spu_dma);
- queue_work(aica_queue, &(spu_working.spu_dma_work));
+ /*get the queue to do the work */
+ queue_work(aica_queue, &(dreamcastcard->spu_dma_work));
/* Timer may already be running */
if (unlikely(dreamcastcard->timer.data)) {
mod_timer(&dreamcastcard->timer, jiffies + 4);
return;
}
init_timer(&(dreamcastcard->timer));
- dreamcastcard->timer.data = (unsigned long)substream;
+ dreamcastcard->timer.data = (unsigned long) substream;
dreamcastcard->timer.function = aica_period_elapsed;
dreamcastcard->timer.expires = jiffies + 4;
add_timer(&(dreamcastcard->timer));
@@ -366,7 +354,9 @@
*substream)
{
struct snd_card_aica *dreamcastcard = substream->pcm->private_data;
- del_timer(&dreamcastcard->timer);
+ flush_workqueue(aica_queue);
+ if (dreamcastcard->timer.data)
+ del_timer(&dreamcastcard->timer);
kfree(dreamcastcard->channel);
spu_disable();
return 0;
@@ -385,7 +375,8 @@
{
/* Allocate a DMA buffer using ALSA built-ins */
return
- snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(hw_params));
+ snd_pcm_lib_malloc_pages(substream,
+ params_buffer_bytes(hw_params));
}
static int snd_aicapcm_pcm_prepare(struct snd_pcm_substream
@@ -402,15 +393,11 @@
static int snd_aicapcm_pcm_trigger(struct snd_pcm_substream
*substream, int cmd)
{
- struct snd_card_aica *dreamcastcard;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
spu_begin_dma(substream);
break;
case SNDRV_PCM_TRIGGER_STOP:
- dreamcastcard = substream->pcm->private_data;
- if (dreamcastcard->timer.data)
- del_timer(&dreamcastcard->timer);
aica_chn_halt();
break;
default:
@@ -444,7 +431,8 @@
int err;
/* AICA has no capture ability */
err =
- snd_pcm_new(dreamcastcard->card, "AICA PCM", pcm_index, 1, 0, &pcm);
+ snd_pcm_new(dreamcastcard->card, "AICA PCM", pcm_index, 1, 0,
+ &pcm);
if (unlikely(err < 0))
return err;
pcm->private_data = dreamcastcard;
@@ -524,9 +512,7 @@
dreamcastcard->channel->vol = ucontrol->value.integer.value[0];
dreamcastcard->master_volume = ucontrol->value.integer.value[0];
spu_memload(AICA_CHANNEL0_CONTROL_OFFSET,
- dreamcastcard->channel,
- sizeof(struct aica_channel));
-
+ dreamcastcard->channel, sizeof(struct aica_channel));
return 1;
}
@@ -610,6 +596,8 @@
strcpy(dreamcastcard->card->shortname, SND_AICA_DRIVER);
strcpy(dreamcastcard->card->longname,
"Yamaha AICA Super Intelligent Sound Processor for SEGA Dreamcast");
+ /* Prepare to use the queue */
+ INIT_WORK(&(dreamcastcard->spu_dma_work), run_spu_dma);
/* Load the PCM 'chip' */
err = snd_aicapcmchip(dreamcastcard, 0);
if (unlikely(err < 0))
@@ -663,8 +651,10 @@
static void __exit aica_exit(void)
{
- /* Destroy the aica kernel thread */
- destroy_workqueue(aica_queue);
+ /* Destroy the aica kernel thread *
+ * being extra cautious to check if it exists*/
+ if (likely(aica_queue))
+ destroy_workqueue(aica_queue);
platform_device_unregister(pd);
platform_driver_unregister(&snd_aica_driver);
/* Kill any sound still playing and reset ARM7 to safe state */
diff -ruN aicaold/aica.h aicanew/aica.h
--- aicaold/aica.h 2007-07-05 23:01:39.000000000 +0100
+++ aicanew/aica.h 2007-07-06 21:37:38.000000000 +0100
@@ -69,6 +69,7 @@
};
struct snd_card_aica {
+ struct work_struct spu_dma_work;
struct snd_card *card;
struct aica_channel *channel;
struct snd_pcm_substream *substream;