From fa00e046b41663cbda9b1affc0594669e5f14219 Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Fri, 10 Apr 2009 12:20:45 +0200 Subject: [ALSA] hda_intel: fix unexpected ring buffer positions I found two issues with ICH7-M (it should be related to other HDA chipsets as well): - the ring buffer position is not reset when stream restarts (after xrun) - solved by moving azx_stream_reset() call from open() to prepare() callback and reset posbuf to zero (it might be filled with hw later than position() callback is called) - irq_ignore flag should be set also when ring buffer memory area is not changed in prepare() callback - this patch replaces irq_ignore with more universal check based on jiffies clock Signed-off-by: Jaroslav Kysela --- sound/pci/hda/hda_intel.c | 39 +++++++++++++++++++++++++-------------- 1 file changed, 25 insertions(+), 14 deletions(-) (limited to 'sound') diff --git a/sound/pci/hda/hda_intel.c b/sound/pci/hda/hda_intel.c index 30829ee..6d3b927 100644 --- a/sound/pci/hda/hda_intel.c +++ b/sound/pci/hda/hda_intel.c @@ -312,6 +312,9 @@ struct azx_dev { unsigned int period_bytes; /* size of the period in bytes */ unsigned int frags; /* number for period in the play buffer */ unsigned int fifo_size; /* FIFO size */ + unsigned int start_flag: 1; /* stream full start flag */ + unsigned long start_jiffies; /* start + minimum jiffies */ + unsigned long min_jiffies; /* minimum jiffies before position is valid */ void __iomem *sd_addr; /* stream descriptor pointer */ @@ -330,7 +333,6 @@ struct azx_dev { unsigned int opened :1; unsigned int running :1; unsigned int irq_pending :1; - unsigned int irq_ignore :1; /* * For VIA: * A flag to ensure DMA position is 0 @@ -975,7 +977,7 @@ static irqreturn_t azx_interrupt(int irq, void *dev_id) struct azx *chip = dev_id; struct azx_dev *azx_dev; u32 status; - int i; + int i, ok; spin_lock(&chip->reg_lock); @@ -991,18 +993,14 @@ static irqreturn_t azx_interrupt(int irq, void *dev_id) azx_sd_writeb(azx_dev, SD_STS, SD_INT_MASK); if (!azx_dev->substream || !azx_dev->running) continue; - /* ignore the first dummy IRQ (due to pos_adj) */ - if (azx_dev->irq_ignore) { - azx_dev->irq_ignore = 0; - continue; - } /* check whether this IRQ is really acceptable */ - if (azx_position_ok(chip, azx_dev)) { + ok = azx_position_ok(chip, azx_dev); + if (ok == 1) { azx_dev->irq_pending = 0; spin_unlock(&chip->reg_lock); snd_pcm_period_elapsed(azx_dev->substream); spin_lock(&chip->reg_lock); - } else if (chip->bus && chip->bus->workq) { + } else if (ok == 0 && chip->bus && chip->bus->workq) { /* bogus IRQ, process it later */ azx_dev->irq_pending = 1; queue_work(chip->bus->workq, @@ -1088,7 +1086,6 @@ static int azx_setup_periods(struct azx *chip, bdl = (u32 *)azx_dev->bdl.area; ofs = 0; azx_dev->frags = 0; - azx_dev->irq_ignore = 0; pos_adj = bdl_pos_adj[chip->dev_index]; if (pos_adj > 0) { struct snd_pcm_runtime *runtime = substream->runtime; @@ -1109,7 +1106,6 @@ static int azx_setup_periods(struct azx *chip, &bdl, ofs, pos_adj, 1); if (ofs < 0) goto error; - azx_dev->irq_ignore = 1; } } else pos_adj = 0; @@ -1155,6 +1151,9 @@ static void azx_stream_reset(struct azx *chip, struct azx_dev *azx_dev) while (((val = azx_sd_readb(azx_dev, SD_CTL)) & SD_CTL_STREAM_RESET) && --timeout) ; + + /* reset first position - may not be synced with hw at this time */ + *azx_dev->posbuf = 0; } /* @@ -1409,7 +1408,6 @@ static int azx_pcm_open(struct snd_pcm_substream *substream) snd_pcm_set_sync(substream); mutex_unlock(&chip->open_mutex); - azx_stream_reset(chip, azx_dev); return 0; } @@ -1474,6 +1472,7 @@ static int azx_pcm_prepare(struct snd_pcm_substream *substream) unsigned int bufsize, period_bytes, format_val; int err; + azx_stream_reset(chip, azx_dev); format_val = snd_hda_calc_stream_format(runtime->rate, runtime->channels, runtime->format, @@ -1502,6 +1501,8 @@ static int azx_pcm_prepare(struct snd_pcm_substream *substream) return err; } + azx_dev->min_jiffies = (runtime->period_size * HZ) / + (runtime->rate * 2); azx_setup_controller(chip, azx_dev); if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) azx_dev->fifo_size = azx_sd_readw(azx_dev, SD_FIFOSIZE) + 1; @@ -1518,13 +1519,14 @@ static int azx_pcm_trigger(struct snd_pcm_substream *substream, int cmd) struct azx *chip = apcm->chip; struct azx_dev *azx_dev; struct snd_pcm_substream *s; - int start, nsync = 0, sbits = 0; + int rstart = 0, start, nsync = 0, sbits = 0; int nwait, timeout; switch (cmd) { + case SNDRV_PCM_TRIGGER_START: + rstart = 1; case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: case SNDRV_PCM_TRIGGER_RESUME: - case SNDRV_PCM_TRIGGER_START: start = 1; break; case SNDRV_PCM_TRIGGER_PAUSE_PUSH: @@ -1554,6 +1556,10 @@ static int azx_pcm_trigger(struct snd_pcm_substream *substream, int cmd) if (s->pcm->card != substream->pcm->card) continue; azx_dev = get_azx_dev(s); + if (rstart) { + azx_dev->start_flag = 1; + azx_dev->start_jiffies = jiffies + azx_dev->min_jiffies; + } if (start) azx_stream_start(chip, azx_dev); else @@ -1703,6 +1709,11 @@ static int azx_position_ok(struct azx *chip, struct azx_dev *azx_dev) { unsigned int pos; + if (azx_dev->start_flag && + time_before_eq(jiffies, azx_dev->start_jiffies)) + return -1; /* bogus (too early) interrupt */ + azx_dev->start_flag = 0; + pos = azx_get_position(chip, azx_dev); if (chip->position_fix == POS_FIX_AUTO) { if (!pos) { -- cgit v1.1 From bbf6ad1399e9516b0a95de3ad58ffbaed670e4cc Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Fri, 10 Apr 2009 12:28:58 +0200 Subject: [ALSA] pcm-midlevel: Add more strict buffer position checks based on jiffies Some drivers like Intel8x0 or Intel HDA are broken for some hardware variants. This patch adds more strict buffer position checks based on jiffies when internal hw_ptr is updated. Enable xrun_debug to see mangling of wrong positions. As a side effect, the hw_ptr interrupt update routine might do slightly better job when many interrupts are lost. Signed-off-by: Jaroslav Kysela --- sound/core/pcm_lib.c | 47 +++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 39 insertions(+), 8 deletions(-) (limited to 'sound') diff --git a/sound/core/pcm_lib.c b/sound/core/pcm_lib.c index fbb2e39..63d088f 100644 --- a/sound/core/pcm_lib.c +++ b/sound/core/pcm_lib.c @@ -209,9 +209,11 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) { struct snd_pcm_runtime *runtime = substream->runtime; snd_pcm_uframes_t pos; - snd_pcm_uframes_t new_hw_ptr, hw_ptr_interrupt, hw_base; - snd_pcm_sframes_t delta; + snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_ptr_interrupt, hw_base; + snd_pcm_sframes_t hdelta, delta; + unsigned long jdelta; + old_hw_ptr = runtime->status->hw_ptr; pos = snd_pcm_update_hw_ptr_pos(substream, runtime); if (pos == SNDRV_PCM_POS_XRUN) { xrun(substream); @@ -247,7 +249,30 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; } } - if (delta > runtime->period_size) { + hdelta = new_hw_ptr - old_hw_ptr; + jdelta = jiffies - runtime->hw_ptr_jiffies; + if (((hdelta * HZ) / runtime->rate) > jdelta + HZ/100) { + delta = jdelta / + (((runtime->period_size * HZ) / runtime->rate) + + HZ/100); + hw_ptr_error(substream, + "hw_ptr skipping! [Q] " + "(pos=%ld, delta=%ld, period=%ld, " + "jdelta=%lu/%lu/%lu)\n", + (long)pos, (long)hdelta, + (long)runtime->period_size, jdelta, + ((hdelta * HZ) / runtime->rate), delta); + hw_ptr_interrupt = runtime->hw_ptr_interrupt + + runtime->period_size * delta; + if (hw_ptr_interrupt >= runtime->boundary) + hw_ptr_interrupt -= runtime->boundary; + /* rebase to interrupt position */ + hw_base = new_hw_ptr = hw_ptr_interrupt; + /* align hw_base to buffer_size */ + hw_base -= hw_base % runtime->buffer_size; + delta = 0; + } + if (delta > runtime->period_size + runtime->period_size / 2) { hw_ptr_error(substream, "Lost interrupts? " "(stream=%i, delta=%ld, intr_ptr=%ld)\n", @@ -263,6 +288,7 @@ static int snd_pcm_update_hw_ptr_interrupt(struct snd_pcm_substream *substream) runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; + runtime->hw_ptr_jiffies = jiffies; runtime->hw_ptr_interrupt = hw_ptr_interrupt; return snd_pcm_update_hw_ptr_post(substream, runtime); @@ -275,6 +301,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) snd_pcm_uframes_t pos; snd_pcm_uframes_t old_hw_ptr, new_hw_ptr, hw_base; snd_pcm_sframes_t delta; + unsigned long jdelta; old_hw_ptr = runtime->status->hw_ptr; pos = snd_pcm_update_hw_ptr_pos(substream, runtime); @@ -286,14 +313,15 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) new_hw_ptr = hw_base + pos; delta = new_hw_ptr - old_hw_ptr; + jdelta = jiffies - runtime->hw_ptr_jiffies; if (delta < 0) { delta += runtime->buffer_size; if (delta < 0) { hw_ptr_error(substream, "Unexpected hw_pointer value [2] " - "(stream=%i, pos=%ld, old_ptr=%ld)\n", + "(stream=%i, pos=%ld, old_ptr=%ld, jdelta=%li)\n", substream->stream, (long)pos, - (long)old_hw_ptr); + (long)old_hw_ptr, jdelta); return 0; } hw_base += runtime->buffer_size; @@ -301,12 +329,13 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) hw_base = 0; new_hw_ptr = hw_base + pos; } - if (delta > runtime->period_size && runtime->periods > 1) { + if (((delta * HZ) / runtime->rate) > jdelta + HZ/100) { hw_ptr_error(substream, "hw_ptr skipping! " - "(pos=%ld, delta=%ld, period=%ld)\n", + "(pos=%ld, delta=%ld, period=%ld, jdelta=%lu/%lu)\n", (long)pos, (long)delta, - (long)runtime->period_size); + (long)runtime->period_size, jdelta, + ((delta * HZ) / runtime->rate)); return 0; } if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK && @@ -315,6 +344,7 @@ int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream) runtime->hw_ptr_base = hw_base; runtime->status->hw_ptr = new_hw_ptr; + runtime->hw_ptr_jiffies = jiffies; return snd_pcm_update_hw_ptr_post(substream, runtime); } @@ -1441,6 +1471,7 @@ static int snd_pcm_lib_ioctl_reset(struct snd_pcm_substream *substream, runtime->status->hw_ptr %= runtime->buffer_size; else runtime->status->hw_ptr = 0; + runtime->hw_ptr_jiffies = jiffies; snd_pcm_stream_unlock_irqrestore(substream, flags); return 0; } -- cgit v1.1 From 920e4ae31cb113328e617f4a0663fb17d7b09124 Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Mon, 13 Apr 2009 20:45:42 +0200 Subject: [ALSA] intel8x0: an attempt to make ac97_clock measurement more reliable - use monotonic posix clock to measure time - try to avoid reading zero from PICB (position in current buffer) register - show also measured samples - when clock is near 41000 or 44100, use exactly these values (they appears to be reference clocks for hardware manufacturers) Signed-off-by: Jaroslav Kysela --- sound/pci/intel8x0.c | 37 ++++++++++++++++++++++++++++--------- 1 file changed, 28 insertions(+), 9 deletions(-) (limited to 'sound') diff --git a/sound/pci/intel8x0.c b/sound/pci/intel8x0.c index 5764881..c86ff49 100644 --- a/sound/pci/intel8x0.c +++ b/sound/pci/intel8x0.c @@ -2661,8 +2661,9 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) struct snd_pcm_substream *subs; struct ichdev *ichdev; unsigned long port; - unsigned long pos, t; - struct timeval start_time, stop_time; + unsigned long pos, pos1, t; + int civ, timeout = 1000; + struct timespec start_time, stop_time; if (chip->ac97_bus->clock != 48000) return; /* specified in module option */ @@ -2693,16 +2694,27 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) iputbyte(chip, port + ICH_REG_OFF_CR, ICH_IOCE); iputdword(chip, ICHREG(ALI_DMACR), 1 << ichdev->ali_slot); } - do_gettimeofday(&start_time); + do_posix_clock_monotonic_gettime(&start_time); spin_unlock_irq(&chip->reg_lock); msleep(50); spin_lock_irq(&chip->reg_lock); /* check the position */ + do { + civ = igetbyte(chip, ichdev->reg_offset + ICH_REG_OFF_CIV); + pos1 = igetword(chip, ichdev->reg_offset + ichdev->roff_picb); + if (pos1 == 0) { + udelay(10); + continue; + } + if (civ == igetbyte(chip, ichdev->reg_offset + ICH_REG_OFF_CIV) && + pos1 == igetword(chip, ichdev->reg_offset + ichdev->roff_picb)) + break; + } while (timeout--); pos = ichdev->fragsize1; - pos -= igetword(chip, ichdev->reg_offset + ichdev->roff_picb) << ichdev->pos_shift; + pos -= pos1 << ichdev->pos_shift; pos += ichdev->position; chip->in_measurement = 0; - do_gettimeofday(&stop_time); + do_posix_clock_monotonic_gettime(&stop_time); /* stop */ if (chip->device_type == DEVICE_ALI) { iputdword(chip, ICHREG(ALI_DMACR), 1 << (ichdev->ali_slot + 16)); @@ -2717,19 +2729,26 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) iputbyte(chip, port + ICH_REG_OFF_CR, ICH_RESETREGS); spin_unlock_irq(&chip->reg_lock); + pos /= 4; t = stop_time.tv_sec - start_time.tv_sec; t *= 1000000; - t += stop_time.tv_usec - start_time.tv_usec; - printk(KERN_INFO "%s: measured %lu usecs\n", __func__, t); + t += (stop_time.tv_nsec - start_time.tv_nsec) / 1000; + printk(KERN_INFO "%s: measured %lu usecs (%lu samples)\n", __func__, t, pos); if (t == 0) { - snd_printk(KERN_ERR "?? calculation error..\n"); + snd_printk(KERN_ERR "intel8x0: ?? calculation error..\n"); return; } - pos = (pos / 4) * 1000; + pos *= 1000; pos = (pos / t) * 1000 + ((pos % t) * 1000) / t; if (pos < 40000 || pos >= 60000) /* abnormal value. hw problem? */ printk(KERN_INFO "intel8x0: measured clock %ld rejected\n", pos); + else if (pos > 40500 || pos < 41500) + /* first exception - 41000Hz reference clock */ + chip->ac97_bus->clock = 41000; + else if (pos > 43600 || pos < 44600) + /* second exception - 44100HZ reference clock */ + chip->ac97_bus->clock = 44100; else if (pos < 47500 || pos > 48500) /* not 48000Hz, tuning the clock.. */ chip->ac97_bus->clock = (chip->ac97_bus->clock * 48000) / pos; -- cgit v1.1 From da2436a23c038055b1da6fe30b6ea2886b1e07b0 Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Mon, 13 Apr 2009 21:31:25 +0200 Subject: [ALSA] intel8x0: do not use zero value from PICB register It seems that the zero value from the PICB (position in current buffer) register is not reliable. Use jiffies to correct returned value from the ring buffer pointer callback. Signed-off-by: Jaroslav Kysela --- sound/pci/intel8x0.c | 43 +++++++++++++++++++++++++++++++++---------- 1 file changed, 33 insertions(+), 10 deletions(-) (limited to 'sound') diff --git a/sound/pci/intel8x0.c b/sound/pci/intel8x0.c index c86ff49..6962f94 100644 --- a/sound/pci/intel8x0.c +++ b/sound/pci/intel8x0.c @@ -355,6 +355,9 @@ struct ichdev { unsigned int fragsize1; unsigned int position; unsigned int pos_shift; + unsigned int last_pos; + unsigned long last_pos_jiffies; + unsigned int jiffy_to_bytes; int frags; int lvi; int lvi_frag; @@ -838,7 +841,10 @@ static int snd_intel8x0_pcm_trigger(struct snd_pcm_substream *substream, int cmd ichdev->suspended = 0; /* fallthru */ case SNDRV_PCM_TRIGGER_START: + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: val = ICH_IOCE | ICH_STARTBM; + ichdev->last_pos = ichdev->position; + ichdev->last_pos_jiffies = jiffies; break; case SNDRV_PCM_TRIGGER_SUSPEND: ichdev->suspended = 1; @@ -849,9 +855,6 @@ static int snd_intel8x0_pcm_trigger(struct snd_pcm_substream *substream, int cmd case SNDRV_PCM_TRIGGER_PAUSE_PUSH: val = ICH_IOCE; break; - case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: - val = ICH_IOCE | ICH_STARTBM; - break; default: return -EINVAL; } @@ -1045,6 +1048,7 @@ static int snd_intel8x0_pcm_prepare(struct snd_pcm_substream *substream) ichdev->pos_shift = (runtime->sample_bits > 16) ? 2 : 1; } snd_intel8x0_setup_periods(chip, ichdev); + ichdev->jiffy_to_bytes = (runtime->rate * 4 * ichdev->pos_shift) / HZ; return 0; } @@ -1053,7 +1057,7 @@ static snd_pcm_uframes_t snd_intel8x0_pcm_pointer(struct snd_pcm_substream *subs struct intel8x0 *chip = snd_pcm_substream_chip(substream); struct ichdev *ichdev = get_ichdev(substream); size_t ptr1, ptr; - int civ, timeout = 100; + int civ, timeout = 10; unsigned int position; spin_lock(&chip->reg_lock); @@ -1069,9 +1073,19 @@ static snd_pcm_uframes_t snd_intel8x0_pcm_pointer(struct snd_pcm_substream *subs ptr1 == igetword(chip, ichdev->reg_offset + ichdev->roff_picb)) break; } while (timeout--); - ptr1 <<= ichdev->pos_shift; - ptr = ichdev->fragsize1 - ptr1; - ptr += position; + if (ptr1 != 0) { + ptr1 <<= ichdev->pos_shift; + ptr = ichdev->fragsize1 - ptr1; + ptr += position; + ichdev->last_pos = ptr; + ichdev->last_pos_jiffies = jiffies; + } else { + ptr1 = jiffies - ichdev->last_pos_jiffies; + if (ptr1) + ptr1 -= 1; + ptr = ichdev->last_pos + ptr1 * ichdev->jiffy_to_bytes; + ptr %= ichdev->size; + } spin_unlock(&chip->reg_lock); if (ptr >= ichdev->size) return 0; @@ -2710,9 +2724,13 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) pos1 == igetword(chip, ichdev->reg_offset + ichdev->roff_picb)) break; } while (timeout--); - pos = ichdev->fragsize1; - pos -= pos1 << ichdev->pos_shift; - pos += ichdev->position; + if (pos1 == 0) { /* oops, this value is not reliable */ + pos = 0; + } else { + pos = ichdev->fragsize1; + pos -= pos1 << ichdev->pos_shift; + pos += ichdev->position; + } chip->in_measurement = 0; do_posix_clock_monotonic_gettime(&stop_time); /* stop */ @@ -2729,6 +2747,11 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) iputbyte(chip, port + ICH_REG_OFF_CR, ICH_RESETREGS); spin_unlock_irq(&chip->reg_lock); + if (pos == 0) { + snd_printk(KERN_ERR "intel8x0: measure - unreliable DMA position..\n"); + return; + } + pos /= 4; t = stop_time.tv_sec - start_time.tv_sec; t *= 1000000; -- cgit v1.1 From 29dab4fd3176e25dfab6cd763beb02d87973c288 Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Tue, 14 Apr 2009 22:40:04 +0200 Subject: [ALSA] intel8x0: fix wrong conditions in ac97_clock measure routine Also add a little code cleanup. Signed-off-by: Jaroslav Kysela --- sound/pci/intel8x0.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'sound') diff --git a/sound/pci/intel8x0.c b/sound/pci/intel8x0.c index 6962f94..10f8609 100644 --- a/sound/pci/intel8x0.c +++ b/sound/pci/intel8x0.c @@ -2689,7 +2689,7 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) } ichdev = &chip->ichd[ICHD_PCMOUT]; ichdev->physbuf = subs->dma_buffer.addr; - ichdev->size = chip->ichd[ICHD_PCMOUT].fragsize = INTEL8X0_TESTBUF_SIZE; + ichdev->size = ichdev->fragsize = INTEL8X0_TESTBUF_SIZE; ichdev->substream = NULL; /* don't process interrupts */ /* set rate */ @@ -2766,10 +2766,10 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) if (pos < 40000 || pos >= 60000) /* abnormal value. hw problem? */ printk(KERN_INFO "intel8x0: measured clock %ld rejected\n", pos); - else if (pos > 40500 || pos < 41500) + else if (pos > 40500 && pos < 41500) /* first exception - 41000Hz reference clock */ chip->ac97_bus->clock = 41000; - else if (pos > 43600 || pos < 44600) + else if (pos > 43600 && pos < 44600) /* second exception - 44100HZ reference clock */ chip->ac97_bus->clock = 44100; else if (pos < 47500 || pos > 48500) -- cgit v1.1 From 2ec775e7053c82bc90858ede011b35aeb416995b Mon Sep 17 00:00:00 2001 From: Jaroslav Kysela Date: Wed, 15 Apr 2009 10:16:24 +0200 Subject: [ALSA] intel8x0: add one retry to the ac97_clock measurement routine It seems that on some hardware platforms, the first measurement is wrong. This patch adds second measurement to this case. Signed-off-by: Jaroslav Kysela --- sound/pci/intel8x0.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) (limited to 'sound') diff --git a/sound/pci/intel8x0.c b/sound/pci/intel8x0.c index 10f8609..5dced5b 100644 --- a/sound/pci/intel8x0.c +++ b/sound/pci/intel8x0.c @@ -2676,12 +2676,13 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) struct ichdev *ichdev; unsigned long port; unsigned long pos, pos1, t; - int civ, timeout = 1000; + int civ, timeout = 1000, attempt = 1; struct timespec start_time, stop_time; if (chip->ac97_bus->clock != 48000) return; /* specified in module option */ + __again: subs = chip->pcm[0]->streams[0].substream; if (! subs || subs->dma_buffer.bytes < INTEL8X0_TESTBUF_SIZE) { snd_printk(KERN_WARNING "no playback buffer allocated - aborting measure ac97 clock\n"); @@ -2749,6 +2750,11 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) if (pos == 0) { snd_printk(KERN_ERR "intel8x0: measure - unreliable DMA position..\n"); + __retry: + if (attempt < 2) { + attempt++; + goto __again; + } return; } @@ -2759,14 +2765,15 @@ static void __devinit intel8x0_measure_ac97_clock(struct intel8x0 *chip) printk(KERN_INFO "%s: measured %lu usecs (%lu samples)\n", __func__, t, pos); if (t == 0) { snd_printk(KERN_ERR "intel8x0: ?? calculation error..\n"); - return; + goto __retry; } pos *= 1000; pos = (pos / t) * 1000 + ((pos % t) * 1000) / t; - if (pos < 40000 || pos >= 60000) + if (pos < 40000 || pos >= 60000) { /* abnormal value. hw problem? */ printk(KERN_INFO "intel8x0: measured clock %ld rejected\n", pos); - else if (pos > 40500 && pos < 41500) + goto __retry; + } else if (pos > 40500 && pos < 41500) /* first exception - 41000Hz reference clock */ chip->ac97_bus->clock = 41000; else if (pos > 43600 && pos < 44600) -- cgit v1.1