[ALSA] nm256 - Fix PM and irq handling

NM256 driver
- Fixed the PCM resume - restoring the rate setting
- Fixed the handling of buggy irqs
- Dynamically acquire/release irq handler to make the driver more robust
  to unknown irq storms (as OSS driver does).

Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 70 insertions, 23 deletions

diff --git a/sound/pci/nm256/nm256.c b/sound/pci/nm256/nm256.c
index 7eb20b8f89f6..2bbeb10ff7c4 100644
--- a/sound/pci/nm256/nm256.c
+++ b/sound/pci/nm256/nm256.c
@@ -189,6 +189,7 @@ struct snd_nm256_stream {
         nm256_t *chip;
         snd_pcm_substream_t *substream;
         int running;
+        int suspended;
         
         u32 buf;        /* offset from chip->buffer */
         int bufsize;    /* buffer size in bytes */
@@ -231,8 +232,10 @@ struct snd_nm256 {
         int mixer_status_mask;          /* bit mask to test the mixer status */
 
         int irq;
+        int irq_acks;
         irqreturn_t (*interrupt)(int, void *, struct pt_regs *);
         int badintrcount;               /* counter to check bogus interrupts */
+        struct semaphore irq_mutex;
 
         nm256_stream_t streams[2];
 
@@ -464,6 +467,37 @@ snd_nm256_set_format(nm256_t *chip, nm256_stream_t *s, snd_pcm_substream_t *subs
         }
 }
 
+/* acquire interrupt */
+static int snd_nm256_acquire_irq(nm256_t *chip)
+{
+        down(&chip->irq_mutex);
+        if (chip->irq < 0) {
+                if (request_irq(chip->pci->irq, chip->interrupt, SA_INTERRUPT|SA_SHIRQ,
+                                chip->card->driver, (void*)chip)) {
+                        snd_printk("unable to grab IRQ %d\n", chip->pci->irq);
+                        up(&chip->irq_mutex);
+                        return -EBUSY;
+                }
+                chip->irq = chip->pci->irq;
+        }
+        chip->irq_acks++;
+        up(&chip->irq_mutex);
+        return 0;
+}
+
+/* release interrupt */
+static void snd_nm256_release_irq(nm256_t *chip)
+{
+        down(&chip->irq_mutex);
+        if (chip->irq_acks > 0)
+                chip->irq_acks--;
+        if (chip->irq_acks == 0 && chip->irq >= 0) {
+                free_irq(chip->irq, (void*)chip);
+                chip->irq = -1;
+        }
+        up(&chip->irq_mutex);
+}
+
 /*
  * start / stop
  */
@@ -538,15 +572,19 @@ snd_nm256_playback_trigger(snd_pcm_substream_t *substream, int cmd)
 
         spin_lock(&chip->reg_lock);
         switch (cmd) {
-        case SNDRV_PCM_TRIGGER_START:
         case SNDRV_PCM_TRIGGER_RESUME:
+                s->suspended = 0;
+                /* fallthru */
+        case SNDRV_PCM_TRIGGER_START:
                 if (! s->running) {
                         snd_nm256_playback_start(chip, s, substream);
                         s->running = 1;
                 }
                 break;
-        case SNDRV_PCM_TRIGGER_STOP:
         case SNDRV_PCM_TRIGGER_SUSPEND:
+                s->suspended = 1;
+                /* fallthru */
+        case SNDRV_PCM_TRIGGER_STOP:
                 if (s->running) {
                         snd_nm256_playback_stop(chip);
                         s->running = 0;
@@ -818,6 +856,8 @@ snd_nm256_playback_open(snd_pcm_substream_t *substream)
 {
         nm256_t *chip = snd_pcm_substream_chip(substream);
 
+        if (snd_nm256_acquire_irq(chip) < 0)
+                return -EBUSY;
         snd_nm256_setup_stream(chip, &chip->streams[SNDRV_PCM_STREAM_PLAYBACK],
                                substream, &snd_nm256_playback);
         return 0;
@@ -828,6 +868,8 @@ snd_nm256_capture_open(snd_pcm_substream_t *substream)
 {
         nm256_t *chip = snd_pcm_substream_chip(substream);
 
+        if (snd_nm256_acquire_irq(chip) < 0)
+                return -EBUSY;
         snd_nm256_setup_stream(chip, &chip->streams[SNDRV_PCM_STREAM_CAPTURE],
                                substream, &snd_nm256_capture);
         return 0;
@@ -839,6 +881,9 @@ snd_nm256_capture_open(snd_pcm_substream_t *substream)
 static int
 snd_nm256_playback_close(snd_pcm_substream_t *substream)
 {
+        nm256_t *chip = snd_pcm_substream_chip(substream);
+
+        snd_nm256_release_irq(chip);
         return 0;
 }
 
@@ -846,6 +891,9 @@ snd_nm256_playback_close(snd_pcm_substream_t *substream)
 static int
 snd_nm256_capture_close(snd_pcm_substream_t *substream)
 {
+        nm256_t *chip = snd_pcm_substream_chip(substream);
+
+        snd_nm256_release_irq(chip);
         return 0;
 }
 
@@ -915,18 +963,16 @@ snd_nm256_pcm(nm256_t *chip, int device)
 static void
 snd_nm256_init_chip(nm256_t *chip)
 {
-        spin_lock_irq(&chip->reg_lock);
         /* Reset everything. */
         snd_nm256_writeb(chip, 0x0, 0x11);
         snd_nm256_writew(chip, 0x214, 0);
         /* stop sounds.. */
         //snd_nm256_playback_stop(chip);
         //snd_nm256_capture_stop(chip);
-        spin_unlock_irq(&chip->reg_lock);
 }
 
 
-static inline void
+static irqreturn_t
 snd_nm256_intr_check(nm256_t *chip)
 {
         if (chip->badintrcount++ > 1000) {
@@ -947,7 +993,9 @@ snd_nm256_intr_check(nm256_t *chip)
                 if (chip->streams[SNDRV_PCM_STREAM_CAPTURE].running)
                         snd_nm256_capture_stop(chip);
                 chip->badintrcount = 0;
+                return IRQ_HANDLED;
         }
+        return IRQ_NONE;
 }
 
 /* 
@@ -969,10 +1017,8 @@ snd_nm256_interrupt(int irq, void *dev_id, struct pt_regs *dummy)
         status = snd_nm256_readw(chip, NM_INT_REG);
 
         /* Not ours. */
-        if (status == 0) {
-                snd_nm256_intr_check(chip);
-                return IRQ_NONE;
-        }
+        if (status == 0)
+                return snd_nm256_intr_check(chip);
 
         chip->badintrcount = 0;
 
@@ -1036,10 +1082,8 @@ snd_nm256_interrupt_zx(int irq, void *dev_id, struct pt_regs *dummy)
         status = snd_nm256_readl(chip, NM_INT_REG);
 
         /* Not ours. */
-        if (status == 0) {
-                snd_nm256_intr_check(chip);
-                return IRQ_NONE;
-        }
+        if (status == 0)
+                return snd_nm256_intr_check(chip);
 
         chip->badintrcount = 0;
 
@@ -1192,7 +1236,7 @@ snd_nm256_mixer(nm256_t *chip)
                 AC97_PC_BEEP, AC97_PHONE, AC97_MIC, AC97_LINE, AC97_CD,
                 AC97_VIDEO, AC97_AUX, AC97_PCM, AC97_REC_SEL,
                 AC97_REC_GAIN, AC97_GENERAL_PURPOSE, AC97_3D_CONTROL,
-                AC97_EXTENDED_ID,
+                /*AC97_EXTENDED_ID,*/
                 AC97_VENDOR_ID1, AC97_VENDOR_ID2,
                 -1
         };
@@ -1206,6 +1250,7 @@ snd_nm256_mixer(nm256_t *chip)
         for (i = 0; mixer_regs[i] >= 0; i++)
                 set_bit(mixer_regs[i], ac97.reg_accessed);
         ac97.private_data = chip;
+        pbus->no_vra = 1;
         err = snd_ac97_mixer(pbus, &ac97, &chip->ac97);
         if (err < 0)
                 return err;
@@ -1281,6 +1326,7 @@ static int nm256_suspend(snd_card_t *card, pm_message_t state)
 static int nm256_resume(snd_card_t *card)
 {
         nm256_t *chip = card->pm_private_data;
+        int i;
 
         /* Perform a full reset on the hardware */
         pci_enable_device(chip->pci);
@@ -1289,6 +1335,15 @@ static int nm256_resume(snd_card_t *card)
         /* restore ac97 */
         snd_ac97_resume(chip->ac97);
 
+        for (i = 0; i < 2; i++) {
+                nm256_stream_t *s = &chip->streams[i];
+                if (s->substream && s->suspended) {
+                        spin_lock_irq(&chip->reg_lock);
+                        snd_nm256_set_format(chip, s, s->substream);
+                        spin_unlock_irq(&chip->reg_lock);
+                }
+        }
+
         return 0;
 }
 #endif /* CONFIG_PM */
@@ -1360,6 +1415,7 @@ snd_nm256_create(snd_card_t *card, struct pci_dev *pci,
         chip->use_cache = usecache;
         spin_lock_init(&chip->reg_lock);
         chip->irq = -1;
+        init_MUTEX(&chip->irq_mutex);
 
         chip->streams[SNDRV_PCM_STREAM_PLAYBACK].bufsize = play_bufsize;
         chip->streams[SNDRV_PCM_STREAM_CAPTURE].bufsize = capt_bufsize;
@@ -1470,15 +1526,6 @@ snd_nm256_create(snd_card_t *card, struct pci_dev *pci,
                 chip->coeff_buf[SNDRV_PCM_STREAM_CAPTURE] = addr;
         }
 
-        /* acquire interrupt */
-        if (request_irq(pci->irq, chip->interrupt, SA_INTERRUPT|SA_SHIRQ,
-                        card->driver, (void*)chip)) {
-                err = -EBUSY;
-                snd_printk("unable to grab IRQ %d\n", pci->irq);
-                goto __error;
-        }
-        chip->irq = pci->irq;
-
         /* Fixed setting. */
         chip->mixer_base = NM_MIXER_OFFSET;