/* * parse the format descriptor and stores the possible sample rates * on the audioformat table (audio class v1). * * @dev: usb device * @fp: audioformat record * @fmt: the format descriptor * @offset: the start offset of descriptor pointing the rate type * (7 for type I and II, 8 for type II) */ static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audioformat *fp, unsigned char *fmt, int offset) { int nr_rates = fmt[offset]; if (fmt[0] < offset + 1 + 3 * (nr_rates ? nr_rates : 2)) { snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_FORMAT_TYPE desc\n", chip->dev->devnum, fp->iface, fp->altsetting); return -1; } if (nr_rates) { /* * build the rate table and bitmap flags */ int r, idx; fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL); if (fp->rate_table == NULL) { snd_printk(KERN_ERR "cannot malloc\n"); return -1; } 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, 0x0102)) && fp->altsetting == 5 && fp->maxpacksize == 392) rate = 96000; /* Creative VF0470 Live Cam reports 16 kHz instead of 8kHz */ if (rate == 16000 && chip->usb_id == USB_ID(0x041e, 0x4068)) rate = 8000; fp->rate_table[fp->nr_rates] = rate; if (!fp->rate_min || rate < fp->rate_min) fp->rate_min = rate; 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 (!fp->nr_rates) { hwc_debug("All rates were zero. Skipping format!\n"); return -1; } } else { /* continuous rates */ fp->rates = SNDRV_PCM_RATE_CONTINUOUS; fp->rate_min = combine_triple(&fmt[offset + 1]); fp->rate_max = combine_triple(&fmt[offset + 4]); } return 0; }
unsigned int snd_usb_combine_bytes(unsigned char *bytes, int size) { switch (size) { case 1: return *bytes; case 2: return combine_word(bytes); case 3: return combine_triple(bytes); case 4: return combine_quad(bytes); default: return 0; } }
static int detect_usb_format(struct ua101 *ua) { const struct uac_format_type_i_discrete_descriptor *fmt_capture; const struct uac_format_type_i_discrete_descriptor *fmt_playback; const struct usb_endpoint_descriptor *epd; unsigned int rate2; fmt_capture = find_format_descriptor(ua->intf[INTF_CAPTURE]); fmt_playback = find_format_descriptor(ua->intf[INTF_PLAYBACK]); if (!fmt_capture || !fmt_playback) return -ENXIO; switch (fmt_capture->bSubframeSize) { case 3: ua->format_bit = SNDRV_PCM_FMTBIT_S24_3LE; break; case 4: ua->format_bit = SNDRV_PCM_FMTBIT_S32_LE; break; default: dev_err(&ua->dev->dev, "sample width is not 24 or 32 bits\n"); return -ENXIO; } if (fmt_capture->bSubframeSize != fmt_playback->bSubframeSize) { dev_err(&ua->dev->dev, "playback/capture sample widths do not match\n"); return -ENXIO; } if (fmt_capture->bBitResolution != 24 || fmt_playback->bBitResolution != 24) { dev_err(&ua->dev->dev, "sample width is not 24 bits\n"); return -ENXIO; } ua->rate = combine_triple(fmt_capture->tSamFreq[0]); rate2 = combine_triple(fmt_playback->tSamFreq[0]); if (ua->rate != rate2) { dev_err(&ua->dev->dev, "playback/capture rates do not match: %u/%u\n", rate2, ua->rate); return -ENXIO; } switch (ua->dev->speed) { case USB_SPEED_FULL: ua->packets_per_second = 1000; break; case USB_SPEED_HIGH: ua->packets_per_second = 8000; break; default: dev_err(&ua->dev->dev, "unknown device speed\n"); return -ENXIO; } ua->capture.channels = fmt_capture->bNrChannels; ua->playback.channels = fmt_playback->bNrChannels; ua->capture.frame_bytes = fmt_capture->bSubframeSize * ua->capture.channels; ua->playback.frame_bytes = fmt_playback->bSubframeSize * ua->playback.channels; epd = &ua->intf[INTF_CAPTURE]->altsetting[1].endpoint[0].desc; if (!usb_endpoint_is_isoc_in(epd)) { dev_err(&ua->dev->dev, "invalid capture endpoint\n"); return -ENXIO; } ua->capture.usb_pipe = usb_rcvisocpipe(ua->dev, usb_endpoint_num(epd)); ua->capture.max_packet_bytes = le16_to_cpu(epd->wMaxPacketSize); epd = &ua->intf[INTF_PLAYBACK]->altsetting[1].endpoint[0].desc; if (!usb_endpoint_is_isoc_out(epd)) { dev_err(&ua->dev->dev, "invalid playback endpoint\n"); return -ENXIO; } ua->playback.usb_pipe = usb_sndisocpipe(ua->dev, usb_endpoint_num(epd)); ua->playback.max_packet_bytes = le16_to_cpu(epd->wMaxPacketSize); return 0; }