On Wed, 06 Apr 2016 11:22:43 +0200, Kailang wrote: > > > > > -----Original Message----- > > From: Takashi Iwai [mailto:tiwai@xxxxxxx] > > Sent: Wednesday, April 06, 2016 4:57 PM > > To: Kailang > > Cc: (alsa-devel@xxxxxxxxxxxxxxxx) > > Subject: Re: Dell USB audio driver workaround > > > > On Wed, 06 Apr 2016 08:29:12 +0200, > > Kailang wrote: > > > > > > Hi Takashi, > > > > > > Dell had USB dock. > > > Maybe firmware issue, the master volume always keep at 0x57. > > > Attach patch will fix it to keep at Max volume. > > > > > > Could you help us to update it? > > > > Well, I don't get how this patch works.. > > > > > diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c index > > > 4f85757..84d9a4e 100644 > > > --- a/sound/usb/mixer.c > > > +++ b/sound/usb/mixer.c > > > @@ -846,6 +846,12 @@ static void volume_control_quirks(struct > > > usb_mixer_elem_info *cval, { > > > struct snd_usb_audio *chip = cval->head.mixer->chip; > > > switch (chip->usb_id) { > > > + case USB_ID(0x0bda, 0x4014): /* Dell workaround */ > > > + if (strstr(kctl->id.name, "Playback Volume") != NULL) { > > > + cval->min = 0x0000; > > > + cval->max = 0x0000; > > > + } > > > + break; > > > > So, this means that this value has to be fixed to 0? > > If yes, can't we simply remove this volume instead? > > Yes, but it need to set Max volume to 0. This is test on my site. > Because it will rewrite 0x57 value to codec register when driver is loaded. > And keep 0x57 volume value all the time. So, Master volume will lower than windows machine. > This case which driver fail to build the alsa mixer(This is firmware cause it). So, no hardware volume control on this. > If the Max volume value is 0, system will not set default value 0x57 for first time loading driver. Which values (min/max) does this FU take and which values are buggy? Judging from your description, the firmware gives the bogus max value (white min value = 0) and a volume higher than zero is attenuation? Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
