1 files changed, 159 insertions, 184 deletions

diff --git a/sound/usb/usbaudio.c b/sound/usb/usbaudio.c
index eec32e1a3020..823296d7d578 100644
--- a/sound/usb/usbaudio.c
+++ b/sound/usb/usbaudio.c
@@ -107,7 +107,7 @@ MODULE_PARM_DESC(ignore_ctl_error,
 #define MAX_PACKS_HS    (MAX_PACKS * 8) /* in high speed mode */
 #define MAX_URBS        8
 #define SYNC_URBS       4       /* always four urbs for sync */
-#define MIN_PACKS_URB   1       /* minimum 1 packet per urb */
+#define MAX_QUEUE       24      /* try not to exceed this queue length, in ms */
 
 struct audioformat {
         struct list_head list;
@@ -121,6 +121,7 @@ struct audioformat {
         unsigned char attributes;       /* corresponding attributes of cs endpoint */
         unsigned char endpoint;         /* endpoint */
         unsigned char ep_attr;          /* endpoint attributes */
+        unsigned char datainterval;     /* log_2 of data packet interval */
         unsigned int maxpacksize;       /* max. packet size */
         unsigned int rates;             /* rate bitmasks */
         unsigned int rate_min, rate_max;        /* min/max rates */
@@ -170,7 +171,6 @@ struct snd_usb_substream {
         unsigned int curframesize;      /* current packet size in frames (for capture) */
         unsigned int fill_max: 1;       /* fill max packet size always */
         unsigned int fmt_type;          /* USB audio format type (1-3) */
-        unsigned int packs_per_ms;      /* packets per millisecond (for playback) */
 
         unsigned int running: 1;        /* running status */
 
@@ -525,7 +525,7 @@ static int snd_usb_audio_next_packet_size(struct snd_usb_substream *subs)
 /*
  * Prepare urb for streaming before playback starts or when paused.
  *
- * We don't have any data, so we send a frame of silence.
+ * We don't have any data, so we send silence.
  */
 static int prepare_nodata_playback_urb(struct snd_usb_substream *subs,
                                        struct snd_pcm_runtime *runtime,
@@ -537,13 +537,13 @@ static int prepare_nodata_playback_urb(struct snd_usb_substream *subs,
 
         offs = 0;
         urb->dev = ctx->subs->dev;
-        urb->number_of_packets = subs->packs_per_ms;
-        for (i = 0; i < subs->packs_per_ms; ++i) {
+        for (i = 0; i < ctx->packets; ++i) {
                 counts = snd_usb_audio_next_packet_size(subs);
                 urb->iso_frame_desc[i].offset = offs * stride;
                 urb->iso_frame_desc[i].length = counts * stride;
                 offs += counts;
         }
+        urb->number_of_packets = ctx->packets;
         urb->transfer_buffer_length = offs * stride;
         memset(urb->transfer_buffer,
                subs->cur_audiofmt->format == SNDRV_PCM_FORMAT_U8 ? 0x80 : 0,
@@ -607,9 +607,7 @@ static int prepare_playback_urb(struct snd_usb_substream *subs,
                                 break;
                         }
                 }
-                /* finish at the frame boundary at/after the period boundary */
-                if (period_elapsed &&
-                    (i & (subs->packs_per_ms - 1)) == subs->packs_per_ms - 1)
+                if (period_elapsed) /* finish at the period boundary */
                         break;
         }
         if (subs->hwptr_done + offs > runtime->buffer_size) {
@@ -1034,9 +1032,9 @@ static void release_substream_urbs(struct snd_usb_substream *subs, int force)
 static int init_substream_urbs(struct snd_usb_substream *subs, unsigned int period_bytes,
                                unsigned int rate, unsigned int frame_bits)
 {
-        unsigned int maxsize, n, i;
+        unsigned int maxsize, i;
         int is_playback = subs->direction == SNDRV_PCM_STREAM_PLAYBACK;
-        unsigned int npacks[MAX_URBS], urb_packs, total_packs, packs_per_ms;
+        unsigned int urb_packs, total_packs, packs_per_ms;
 
         /* calculate the frequency in 16.16 format */
         if (snd_usb_get_speed(subs->dev) == USB_SPEED_FULL)
@@ -1067,11 +1065,9 @@ static int init_substream_urbs(struct snd_usb_substream *subs, unsigned int peri
                 packs_per_ms = 8 >> subs->datainterval;
         else
                 packs_per_ms = 1;
-        subs->packs_per_ms = packs_per_ms;
 
         if (is_playback) {
-                urb_packs = nrpacks;
-                urb_packs = max(urb_packs, (unsigned int)MIN_PACKS_URB);
+                urb_packs = max(nrpacks, 1);
                 urb_packs = min(urb_packs, (unsigned int)MAX_PACKS);
         } else
                 urb_packs = 1;
@@ -1079,7 +1075,7 @@ static int init_substream_urbs(struct snd_usb_substream *subs, unsigned int peri
 
         /* decide how many packets to be used */
         if (is_playback) {
-                unsigned int minsize;
+                unsigned int minsize, maxpacks;
                 /* determine how small a packet can be */
                 minsize = (subs->freqn >> (16 - subs->datainterval))
                           * (frame_bits >> 3);
@@ -1088,13 +1084,17 @@ static int init_substream_urbs(struct snd_usb_substream *subs, unsigned int peri
                         minsize -= minsize >> 3;
                 minsize = max(minsize, 1u);
                 total_packs = (period_bytes + minsize - 1) / minsize;
-                /* round up to multiple of packs_per_ms */
-                total_packs = (total_packs + packs_per_ms - 1)
-                                & ~(packs_per_ms - 1);
                 /* we need at least two URBs for queueing */
-                if (total_packs < 2 * MIN_PACKS_URB * packs_per_ms)
-                        total_packs = 2 * MIN_PACKS_URB * packs_per_ms;
+                if (total_packs < 2) {
+                        total_packs = 2;
+                } else {
+                        /* and we don't want too long a queue either */
+                        maxpacks = max(MAX_QUEUE * packs_per_ms, urb_packs * 2);
+                        total_packs = min(total_packs, maxpacks);
+                }
         } else {
+                while (urb_packs > 1 && urb_packs * maxsize >= period_bytes)
+                        urb_packs >>= 1;
                 total_packs = MAX_URBS * urb_packs;
         }
         subs->nurbs = (total_packs + urb_packs - 1) / urb_packs;
@@ -1102,31 +1102,11 @@ static int init_substream_urbs(struct snd_usb_substream *subs, unsigned int peri
                 /* too much... */
                 subs->nurbs = MAX_URBS;
                 total_packs = MAX_URBS * urb_packs;
-        }
-        n = total_packs;
-        for (i = 0; i < subs->nurbs; i++) {
-                npacks[i] = n > urb_packs ? urb_packs : n;
-                n -= urb_packs;
-        }
-        if (subs->nurbs <= 1) {
+        } else if (subs->nurbs < 2) {
                 /* too little - we need at least two packets
                  * to ensure contiguous playback/capture
                  */
                 subs->nurbs = 2;
-                npacks[0] = (total_packs + 1) / 2;
-                npacks[1] = total_packs - npacks[0];
-        } else if (npacks[subs->nurbs-1] < MIN_PACKS_URB * packs_per_ms) {
-                /* the last packet is too small.. */
-                if (subs->nurbs > 2) {
-                        /* merge to the first one */
-                        npacks[0] += npacks[subs->nurbs - 1];
-                        subs->nurbs--;
-                } else {
-                        /* divide to two */
-                        subs->nurbs = 2;
-                        npacks[0] = (total_packs + 1) / 2;
-                        npacks[1] = total_packs - npacks[0];
-                }
         }
 
         /* allocate and initialize data urbs */
@@ -1134,7 +1114,8 @@ static int init_substream_urbs(struct snd_usb_substream *subs, unsigned int peri
                 struct snd_urb_ctx *u = &subs->dataurb[i];
                 u->index = i;
                 u->subs = subs;
-                u->packets = npacks[i];
+                u->packets = (i + 1) * total_packs / subs->nurbs
+                        - i * total_packs / subs->nurbs;
                 u->buffer_size = maxsize * u->packets;
                 if (subs->fmt_type == USB_FORMAT_TYPE_II)
                         u->packets++; /* for transfer delimiter */
@@ -1292,14 +1273,14 @@ static int init_usb_sample_rate(struct usb_device *dev, int iface,
                 if ((err = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0), SET_CUR,
                                            USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_OUT,
                                            SAMPLING_FREQ_CONTROL << 8, ep, data, 3, 1000)) < 0) {
-                        snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d to ep 0x%x\n",
+                        snd_printk(KERN_ERR "%d:%d:%d: cannot set freq %d to ep %#x\n",
                                    dev->devnum, iface, fmt->altsetting, rate, ep);
                         return err;
                 }
                 if ((err = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), GET_CUR,
                                            USB_TYPE_CLASS|USB_RECIP_ENDPOINT|USB_DIR_IN,
                                            SAMPLING_FREQ_CONTROL << 8, ep, data, 3, 1000)) < 0) {
-                        snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq at ep 0x%x\n",
+                        snd_printk(KERN_WARNING "%d:%d:%d: cannot get freq at ep %#x\n",
                                    dev->devnum, iface, fmt->altsetting, ep);
                         return 0; /* some devices don't support reading */
                 }
@@ -1365,12 +1346,7 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
                 subs->datapipe = usb_sndisocpipe(dev, ep);
         else
                 subs->datapipe = usb_rcvisocpipe(dev, ep);
-        if (snd_usb_get_speed(subs->dev) == USB_SPEED_HIGH &&
-            get_endpoint(alts, 0)->bInterval >= 1 &&
-            get_endpoint(alts, 0)->bInterval <= 4)
-                subs->datainterval = get_endpoint(alts, 0)->bInterval - 1;
-        else
-                subs->datainterval = 0;
+        subs->datainterval = fmt->datainterval;
         subs->syncpipe = subs->syncinterval = 0;
         subs->maxpacksize = fmt->maxpacksize;
         subs->fill_max = 0;
@@ -1431,9 +1407,11 @@ static int set_format(struct snd_usb_substream *subs, struct audioformat *fmt)
         subs->cur_audiofmt = fmt;
 
 #if 0
-        printk("setting done: format = %d, rate = %d..%d, channels = %d\n",
+        printk(KERN_DEBUG
+               "setting done: format = %d, rate = %d..%d, channels = %d\n",
                fmt->format, fmt->rate_min, fmt->rate_max, fmt->channels);
-        printk("  datapipe = 0x%0x, syncpipe = 0x%0x\n",
+        printk(KERN_DEBUG
+               "  datapipe = 0x%0x, syncpipe = 0x%0x\n",
                subs->datapipe, subs->syncpipe);
 #endif
 
@@ -1468,7 +1446,7 @@ static int snd_usb_hw_params(struct snd_pcm_substream *substream,
         channels = params_channels(hw_params);
         fmt = find_format(subs, format, rate, channels);
         if (!fmt) {
-                snd_printd(KERN_DEBUG "cannot set format: format = 0x%x, rate = %d, channels = %d\n",
+                snd_printd(KERN_DEBUG "cannot set format: format = %#x, rate = %d, channels = %d\n",
                            format, rate, channels);
                 return -EINVAL;
         }
@@ -1581,11 +1559,15 @@ static struct snd_pcm_hardware snd_usb_hardware =
 #define hwc_debug(fmt, args...) /**/
 #endif
 
-static int hw_check_valid_format(struct snd_pcm_hw_params *params, struct audioformat *fp)
+static int hw_check_valid_format(struct snd_usb_substream *subs,
+                                 struct snd_pcm_hw_params *params,
+                                 struct audioformat *fp)
 {
         struct snd_interval *it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_RATE);
         struct snd_interval *ct = hw_param_interval(params, SNDRV_PCM_HW_PARAM_CHANNELS);
         struct snd_mask *fmts = hw_param_mask(params, SNDRV_PCM_HW_PARAM_FORMAT);
+        struct snd_interval *pt = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
+        unsigned int ptime;
 
         /* check the format */
         if (!snd_mask_test(fmts, fp->format)) {
@@ -1606,6 +1588,14 @@ static int hw_check_valid_format(struct snd_pcm_hw_params *params, struct audiof
                 hwc_debug("   > check: rate_max %d < min %d\n", fp->rate_max, it->min);
                 return 0;
         }
+        /* check whether the period time is >= the data packet interval */
+        if (snd_usb_get_speed(subs->dev) == USB_SPEED_HIGH) {
+                ptime = 125 * (1 << fp->datainterval);
+                if (ptime > pt->max || (ptime == pt->max && pt->openmax)) {
+                        hwc_debug("   > check: ptime %u > max %u\n", ptime, pt->max);
+                        return 0;
+                }
+        }
         return 1;
 }
 
@@ -1624,7 +1614,7 @@ static int hw_rule_rate(struct snd_pcm_hw_params *params,
         list_for_each(p, &subs->fmt_list) {
                 struct audioformat *fp;
                 fp = list_entry(p, struct audioformat, list);
-                if (!hw_check_valid_format(params, fp))
+                if (!hw_check_valid_format(subs, params, fp))
                         continue;
                 if (changed++) {
                         if (rmin > fp->rate_min)
@@ -1678,7 +1668,7 @@ static int hw_rule_channels(struct snd_pcm_hw_params *params,
         list_for_each(p, &subs->fmt_list) {
                 struct audioformat *fp;
                 fp = list_entry(p, struct audioformat, list);
-                if (!hw_check_valid_format(params, fp))
+                if (!hw_check_valid_format(subs, params, fp))
                         continue;
                 if (changed++) {
                         if (rmin > fp->channels)
@@ -1731,7 +1721,7 @@ static int hw_rule_format(struct snd_pcm_hw_params *params,
         list_for_each(p, &subs->fmt_list) {
                 struct audioformat *fp;
                 fp = list_entry(p, struct audioformat, list);
-                if (!hw_check_valid_format(params, fp))
+                if (!hw_check_valid_format(subs, params, fp))
                         continue;
                 fbits |= (1ULL << fp->format);
         }
@@ -1749,95 +1739,42 @@ static int hw_rule_format(struct snd_pcm_hw_params *params,
         return changed;
 }
 
-#define MAX_MASK        64
-
-/*
- * check whether the registered audio formats need special hw-constraints
- */
-static int check_hw_params_convention(struct snd_usb_substream *subs)
+static int hw_rule_period_time(struct snd_pcm_hw_params *params,
+                               struct snd_pcm_hw_rule *rule)
 {
-        int i;
-        u32 *channels;
-        u32 *rates;
-        u32 cmaster, rmaster;
-        u32 rate_min = 0, rate_max = 0;
-        struct list_head *p;
-        int err = 1;
-
-        channels = kcalloc(MAX_MASK, sizeof(u32), GFP_KERNEL);
-        rates = kcalloc(MAX_MASK, sizeof(u32), GFP_KERNEL);
-        if (!channels || !rates) {
-                err = -ENOMEM;
-                goto __out;
-        }
+        struct snd_usb_substream *subs = rule->private;
+        struct audioformat *fp;
+        struct snd_interval *it;
+        unsigned char min_datainterval;
+        unsigned int pmin;
+        int changed;
 
-        list_for_each(p, &subs->fmt_list) {
-                struct audioformat *f;
-                f = list_entry(p, struct audioformat, list);
-                /* unconventional channels? */
-                if (f->channels > 32)
-                        goto __out;
-                /* continuous rate min/max matches? */
-                if (f->rates & SNDRV_PCM_RATE_CONTINUOUS) {
-                        if (rate_min && f->rate_min != rate_min)
-                                goto __out;
-                        if (rate_max && f->rate_max != rate_max)
-                                goto __out;
-                        rate_min = f->rate_min;
-                        rate_max = f->rate_max;
-                }
-                /* combination of continuous rates and fixed rates? */
-                if (rates[f->format] & SNDRV_PCM_RATE_CONTINUOUS) {
-                        if (f->rates != rates[f->format])
-                                goto __out;
-                }
-                if (f->rates & SNDRV_PCM_RATE_CONTINUOUS) {
-                        if (rates[f->format] && rates[f->format] != f->rates)
-                                goto __out;
-                }
-                channels[f->format] |= (1 << f->channels);
-                rates[f->format] |= f->rates;
-                /* needs knot? */
-                if (f->rates & SNDRV_PCM_RATE_KNOT)
-                        goto __out;
-        }
-        /* check whether channels and rates match for all formats */
-        cmaster = rmaster = 0;
-        for (i = 0; i < MAX_MASK; i++) {
-                if (cmaster != channels[i] && cmaster && channels[i])
-                        goto __out;
-                if (rmaster != rates[i] && rmaster && rates[i])
-                        goto __out;
-                if (channels[i])
-                        cmaster = channels[i];
-                if (rates[i])
-                        rmaster = rates[i];
-        }
-        /* check whether channels match for all distinct rates */
-        memset(channels, 0, MAX_MASK * sizeof(u32));
-        list_for_each(p, &subs->fmt_list) {
-                struct audioformat *f;
-                f = list_entry(p, struct audioformat, list);
-                if (f->rates & SNDRV_PCM_RATE_CONTINUOUS)
+        it = hw_param_interval(params, SNDRV_PCM_HW_PARAM_PERIOD_TIME);
+        hwc_debug("hw_rule_period_time: (%u,%u)\n", it->min, it->max);
+        min_datainterval = 0xff;
+        list_for_each_entry(fp, &subs->fmt_list, list) {
+                if (!hw_check_valid_format(subs, params, fp))
                         continue;
-                for (i = 0; i < 32; i++) {
-                        if (f->rates & (1 << i))
-                                channels[i] |= (1 << f->channels);
-                }
+                min_datainterval = min(min_datainterval, fp->datainterval);
+        }
+        if (min_datainterval == 0xff) {
+                hwc_debug("  --> get emtpy\n");
+                it->empty = 1;
+                return -EINVAL;
         }
-        cmaster = 0;
-        for (i = 0; i < 32; i++) {
-                if (cmaster != channels[i] && cmaster && channels[i])
-                        goto __out;
-                if (channels[i])
-                        cmaster = channels[i];
+        pmin = 125 * (1 << min_datainterval);
+        changed = 0;
+        if (it->min < pmin) {
+                it->min = pmin;
+                it->openmin = 0;
+                changed = 1;
         }
-        err = 0;
-
- __out:
-        kfree(channels);
-        kfree(rates);
-        return err;
+        if (snd_interval_checkempty(it)) {
+                it->empty = 1;
+                return -EINVAL;
+        }
+        hwc_debug("  --> (%u,%u) (changed = %d)\n", it->min, it->max, changed);
+        return changed;
 }
 
 /*
@@ -1885,6 +1822,8 @@ static int snd_usb_pcm_check_knot(struct snd_pcm_runtime *runtime,
 static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substream *subs)
 {
         struct list_head *p;
+        unsigned int pt, ptmin;
+        int param_period_time_if_needed;
         int err;
 
         runtime->hw.formats = subs->formats;
@@ -1894,6 +1833,7 @@ static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substre
         runtime->hw.channels_min = 256;
         runtime->hw.channels_max = 0;
         runtime->hw.rates = 0;
+        ptmin = UINT_MAX;
         /* check min/max rates and channels */
         list_for_each(p, &subs->fmt_list) {
                 struct audioformat *fp;
@@ -1912,42 +1852,54 @@ static int setup_hw_info(struct snd_pcm_runtime *runtime, struct snd_usb_substre
                         runtime->hw.period_bytes_min = runtime->hw.period_bytes_max =
                                 fp->frame_size;
                 }
+                pt = 125 * (1 << fp->datainterval);
+                ptmin = min(ptmin, pt);
         }
 
-        /* set the period time minimum 1ms */
-        /* FIXME: high-speed mode allows 125us minimum period, but many parts
-         * in the current code assume the 1ms period.
-         */
+        param_period_time_if_needed = SNDRV_PCM_HW_PARAM_PERIOD_TIME;
+        if (snd_usb_get_speed(subs->dev) != USB_SPEED_HIGH)
+                /* full speed devices have fixed data packet interval */
+                ptmin = 1000;
+        if (ptmin == 1000)
+                /* if period time doesn't go below 1 ms, no rules needed */
+                param_period_time_if_needed = -1;
         snd_pcm_hw_constraint_minmax(runtime, SNDRV_PCM_HW_PARAM_PERIOD_TIME,
-                                     1000 * MIN_PACKS_URB,
-                                     /*(nrpacks * MAX_URBS) * 1000*/ UINT_MAX);
-
-        err = check_hw_params_convention(subs);
-        if (err < 0)
+                                     ptmin, UINT_MAX);
+
+        if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
+                                       hw_rule_rate, subs,
+                                       SNDRV_PCM_HW_PARAM_FORMAT,
+                                       SNDRV_PCM_HW_PARAM_CHANNELS,
+                                       param_period_time_if_needed,
+                                       -1)) < 0)
                 return err;
-        else if (err) {
-                hwc_debug("setting extra hw constraints...\n");
-                if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
-                                               hw_rule_rate, subs,
-                                               SNDRV_PCM_HW_PARAM_FORMAT,
-                                               SNDRV_PCM_HW_PARAM_CHANNELS,
-                                               -1)) < 0)
-                        return err;
-                if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
-                                               hw_rule_channels, subs,
-                                               SNDRV_PCM_HW_PARAM_FORMAT,
-                                               SNDRV_PCM_HW_PARAM_RATE,
-                                               -1)) < 0)
-                        return err;
-                if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
-                                               hw_rule_format, subs,
-                                               SNDRV_PCM_HW_PARAM_RATE,
-                                               SNDRV_PCM_HW_PARAM_CHANNELS,
-                                               -1)) < 0)
-                        return err;
-                if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
+        if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_CHANNELS,
+                                       hw_rule_channels, subs,
+                                       SNDRV_PCM_HW_PARAM_FORMAT,
+                                       SNDRV_PCM_HW_PARAM_RATE,
+                                       param_period_time_if_needed,
+                                       -1)) < 0)
+                return err;
+        if ((err = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_FORMAT,
+                                       hw_rule_format, subs,
+                                       SNDRV_PCM_HW_PARAM_RATE,
+                                       SNDRV_PCM_HW_PARAM_CHANNELS,
+                                       param_period_time_if_needed,
+                                       -1)) < 0)
+                return err;
+        if (param_period_time_if_needed >= 0) {
+                err = snd_pcm_hw_rule_add(runtime, 0,
+                                          SNDRV_PCM_HW_PARAM_PERIOD_TIME,
+                                          hw_rule_period_time, subs,
+                                          SNDRV_PCM_HW_PARAM_FORMAT,
+                                          SNDRV_PCM_HW_PARAM_CHANNELS,
+                                          SNDRV_PCM_HW_PARAM_RATE,
+                                          -1);
+                if (err < 0)
                         return err;
         }
+        if ((err = snd_usb_pcm_check_knot(runtime, subs)) < 0)
+                return err;
         return 0;
 }
 
@@ -2160,7 +2112,8 @@ static void proc_dump_substream_formats(struct snd_usb_substream *subs, struct s
                 fp = list_entry(p, struct audioformat, list);
                 snd_iprintf(buffer, "  Interface %d\n", fp->iface);
                 snd_iprintf(buffer, "    Altset %d\n", fp->altsetting);
-                snd_iprintf(buffer, "    Format: 0x%x\n", fp->format);
+                snd_iprintf(buffer, "    Format: %#x (%d bits)\n",
+                            fp->format, snd_pcm_format_width(fp->format));
                 snd_iprintf(buffer, "    Channels: %d\n", fp->channels);
                 snd_iprintf(buffer, "    Endpoint: %d %s (%s)\n",
                             fp->endpoint & USB_ENDPOINT_NUMBER_MASK,
@@ -2179,8 +2132,11 @@ static void proc_dump_substream_formats(struct snd_usb_substream *subs, struct s
                         }
                         snd_iprintf(buffer, "\n");
                 }
+                if (snd_usb_get_speed(subs->dev) == USB_SPEED_HIGH)
+                        snd_iprintf(buffer, "    Data packet interval: %d us\n",
+                                    125 * (1 << fp->datainterval));
                 // snd_iprintf(buffer, "    Max Packet Size = %d\n", fp->maxpacksize);
-                // snd_iprintf(buffer, "    EP Attribute = 0x%x\n", fp->attributes);
+                // snd_iprintf(buffer, "    EP Attribute = %#x\n", fp->attributes);
         }
 }
 
@@ -2524,7 +2480,6 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
                  * build the rate table and bitmap flags
                  */
                 int r, idx;
-                unsigned int nonzero_rates = 0;
 
                 fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL);
                 if (fp->rate_table == NULL) {
@@ -2532,24 +2487,27 @@ static int parse_audio_format_rates(struct snd_usb_audio *chip, struct audioform
                         return -1;
                 }
 
-                fp->nr_rates = nr_rates;
-                fp->rate_min = fp->rate_max = combine_triple(&fmt[8]);
+                fp->nr_rates = 0;
+                fp->rate_min = fp->rate_max = 0;
                 for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
                         unsigned int rate = combine_triple(&fmt[idx]);
+                        if (!rate)
+                                continue;
                         /* C-Media CM6501 mislabels its 96 kHz altsetting */
                         if (rate == 48000 && nr_rates == 1 &&
-                            chip->usb_id == USB_ID(0x0d8c, 0x0201) &&
+                            (chip->usb_id == USB_ID(0x0d8c, 0x0201) ||
+                             chip->usb_id == USB_ID(0x0d8c, 0x0102)) &&
                             fp->altsetting == 5 && fp->maxpacksize == 392)
                                 rate = 96000;
-                        fp->rate_table[r] = rate;
-                        nonzero_rates |= rate;
-                        if (rate < fp->rate_min)
+                        fp->rate_table[fp->nr_rates] = rate;
+                        if (!fp->rate_min || rate < fp->rate_min)
                                 fp->rate_min = rate;
-                        else if (rate > fp->rate_max)
+                        if (!fp->rate_max || rate > fp->rate_max)
                                 fp->rate_max = rate;
                         fp->rates |= snd_pcm_rate_to_rate_bit(rate);
+                        fp->nr_rates++;
                 }
-                if (!nonzero_rates) {
+                if (!fp->nr_rates) {
                         hwc_debug("All rates were zero. Skipping format!\n");
                         return -1;
                 }
@@ -2619,7 +2577,7 @@ static int parse_audio_format_ii(struct snd_usb_audio *chip, struct audioformat
                 fp->format = SNDRV_PCM_FORMAT_MPEG;
                 break;
         default:
-                snd_printd(KERN_INFO "%d:%u:%d : unknown format tag 0x%x is detected.  processed as MPEG.\n",
+                snd_printd(KERN_INFO "%d:%u:%d : unknown format tag %#x is detected.  processed as MPEG.\n",
                            chip->dev->devnum, fp->iface, fp->altsetting, format);
                 fp->format = SNDRV_PCM_FORMAT_MPEG;
                 break;
@@ -2670,6 +2628,17 @@ static int parse_audio_format(struct snd_usb_audio *chip, struct audioformat *fp
         return 0;
 }
 
+static unsigned char parse_datainterval(struct snd_usb_audio *chip,
+                                        struct usb_host_interface *alts)
+{
+        if (snd_usb_get_speed(chip->dev) == USB_SPEED_HIGH &&
+            get_endpoint(alts, 0)->bInterval >= 1 &&
+            get_endpoint(alts, 0)->bInterval <= 4)
+                return get_endpoint(alts, 0)->bInterval - 1;
+        else
+                return 0;
+}
+
 static int audiophile_skip_setting_quirk(struct snd_usb_audio *chip,
                                          int iface, int altno);
 static int parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
@@ -2775,6 +2744,7 @@ static int parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
                 fp->altset_idx = i;
                 fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
                 fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
+                fp->datainterval = parse_datainterval(chip, alts);
                 fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
                 if (snd_usb_get_speed(dev) == USB_SPEED_HIGH)
                         fp->maxpacksize = (((fp->maxpacksize >> 11) & 3) + 1)
@@ -2817,7 +2787,7 @@ static int parse_audio_endpoints(struct snd_usb_audio *chip, int iface_no)
                         continue;
                 }
 
-                snd_printdd(KERN_INFO "%d:%u:%d: add audio endpoint 0x%x\n", dev->devnum, iface_no, altno, fp->endpoint);
+                snd_printdd(KERN_INFO "%d:%u:%d: add audio endpoint %#x\n", dev->devnum, iface_no, altno, fp->endpoint);
                 err = add_audio_endpoint(chip, stream, fp);
                 if (err < 0) {
                         kfree(fp->rate_table);
@@ -2966,6 +2936,8 @@ static int create_fixed_stream_quirk(struct snd_usb_audio *chip,
                 return -EINVAL;
         }
         alts = &iface->altsetting[fp->altset_idx];
+        fp->datainterval = parse_datainterval(chip, alts);
+        fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
         usb_set_interface(chip->dev, fp->iface, 0);
         init_usb_pitch(chip->dev, fp->iface, alts, fp);
         init_usb_sample_rate(chip->dev, fp->iface, alts, fp, fp->rate_max);
@@ -3059,6 +3031,7 @@ static int create_uaxx_quirk(struct snd_usb_audio *chip,
         fp->iface = altsd->bInterfaceNumber;
         fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
         fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
+        fp->datainterval = 0;
         fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
 
         switch (fp->maxpacksize) {
@@ -3126,6 +3099,7 @@ static int create_ua1000_quirk(struct snd_usb_audio *chip,
         fp->iface = altsd->bInterfaceNumber;
         fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
         fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
+        fp->datainterval = parse_datainterval(chip, alts);
         fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
         fp->rate_max = fp->rate_min = combine_triple(&alts->extra[8]);
 
@@ -3178,6 +3152,7 @@ static int create_ua101_quirk(struct snd_usb_audio *chip,
         fp->iface = altsd->bInterfaceNumber;
         fp->endpoint = get_endpoint(alts, 0)->bEndpointAddress;
         fp->ep_attr = get_endpoint(alts, 0)->bmAttributes;
+        fp->datainterval = parse_datainterval(chip, alts);
         fp->maxpacksize = le16_to_cpu(get_endpoint(alts, 0)->wMaxPacketSize);
         fp->rate_max = fp->rate_min = combine_triple(&alts->extra[15]);
 
@@ -3763,7 +3738,7 @@ static int usb_audio_resume(struct usb_interface *intf)
 
 static int __init snd_usb_audio_init(void)
 {
-        if (nrpacks < MIN_PACKS_URB || nrpacks > MAX_PACKS) {
+        if (nrpacks < 1 || nrpacks > MAX_PACKS) {
                 printk(KERN_WARNING "invalid nrpacks value.\n");
                 return -EINVAL;
         }