[ALSA] aica - fix behaviour in poor resource conditions

Fix behaviour in poor resource conditions.  With this new patch,
tidied with indent and with SNDRV_PCM_TRIGGER_STOP being used.
Signed-off by: Adrian McMenamin <adrian@mcmen.demon.co.uk>

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

2 files changed, 37 insertions, 46 deletions

diff --git a/sound/sh/aica.c b/sound/sh/aica.c
index 97bb86a58622..739786529ca5 100644
--- a/sound/sh/aica.c
+++ b/sound/sh/aica.c
@@ -64,12 +64,6 @@ module_param(enable, bool, 0644);
 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 @@ static void spu_write_wait(void)
                         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 @@ static int aica_dma_transfer(int channels, int buffer_size,
         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 int aica_dma_transfer(int channels, int buffer_size,
 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 @@ static void run_spu_dma(struct work_struct *work)
         } 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 @@ static void aica_period_elapsed(unsigned long timer_var)
         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 @@ static void aica_period_elapsed(unsigned long timer_var)
                 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 @@ static int snd_aicapcm_pcm_close(struct snd_pcm_substream
                                  *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 @@ static int snd_aicapcm_pcm_hw_params(struct snd_pcm_substream
 {
         /* 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_prepare(struct snd_pcm_substream
 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 @@ static int __init snd_aicapcmchip(struct snd_card_aica
         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 @@ static int aica_pcmvolume_put(struct snd_kcontrol *kcontrol,
         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 @@ static int __init snd_aica_probe(struct platform_device *devptr)
         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 int __init aica_init(void)
 
 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 --git a/sound/sh/aica.h b/sound/sh/aica.h
index 0603b5b0376b..8c11e3d10a50 100644
--- a/sound/sh/aica.h
+++ b/sound/sh/aica.h
@@ -69,6 +69,7 @@ struct aica_channel {
 };
 
 struct snd_card_aica {
+        struct work_struct spu_dma_work;
         struct snd_card *card;
         struct aica_channel *channel;
         struct snd_pcm_substream *substream;