- usb_audio_info(mixer->chip, "applying DragonFly dB scale quirk\n");
- kctl->tlv.p = scale;
- kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
- kctl->vd[0].access &= ~SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
+ if (cval->min == 0 && cval->max == 50) {
+ usb_audio_info(mixer->chip, "applying DragonFly dB scale quirk (0-50 variant)\n");
+ kctl->tlv.p = scale;
+ kctl->vd[0].access |= SNDRV_CTL_ELEM_ACCESS_TLV_READ;
+ kctl->vd[0].access &= ~SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
+
+ } else if (cval->min == 0 && cval->max <= 1000) {
+ /* Some other clearly broken DragonFly variant.
+ * At least a 0..53 variant (hw v1.0) exists.
+ */
+ usb_audio_info(mixer->chip, "ignoring too narrow dB range on a DragonFly device");
+ kctl->vd[0].access &= ~SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
+ }