Commit 1b53c116 authored by Geoffrey D. Bennett's avatar Geoffrey D. Bennett Committed by Takashi Iwai
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ALSA: scarlett2: Allow for controls with a "mute mode" 



Gen 2/3 interfaces would only use 0/1 values for input level and
phantom power switch controls. Gen 4 interfaces use the second bit to
indicate that the state should be changed (or is changing), and the
input is to be muted (or is muted) while that happens.

Add a "mute" flag to config items to enable this behaviour for the
level/phantom controls.

Signed-off-by: default avatarGeoffrey D. Bennett <g@b4.vu>
Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/f603cd16079c97fad910087e0302828a289d1c15.1703612638.git.g@b4.vu
parent 4fa07ff7

sound/usb/mixer_scarlett2.c

+28 −3
Original line number Diff line number Diff line
@@ -325,11 +325,18 @@ enum { 
 * A size of 0 indicates that the parameter is a byte-sized Scarlett

 * Gen 4 configuration which is written through the gen4_write_addr

 * location (but still read through the given offset location).

 *

 * Some Gen 4 configuration parameters are written with 0x02 for a

 * desired value of 0x01, and 0x03 for 0x00. These are indicated with

 * mute set to 1. 0x02 and 0x03 are temporary values while the device

 * makes the change and the channel and/or corresponding DSP channel

 * output is muted.

 */

struct scarlett2_config {

	u16 offset;

	u8 size;

	u8 activate;

	u8 mute;

};



struct scarlett2_config_set {
@@ -2177,6 +2184,15 @@ static int scarlett2_usb_get_meter_levels(struct usb_mixer_interface *mixer, 
	return 0;

}



/* For config items with mute=1, xor bits 0 & 1 together to get the

 * current/next state. This won't have any effect on values which are

 * only ever 0/1.

 */

static uint8_t scarlett2_decode_muteable(uint8_t v)

{

	return (v ^ (v >> 1)) & 1;

}



/*** Control Functions ***/



/* helper function to create a new control */
@@ -2798,7 +2814,8 @@ static int scarlett2_level_enum_ctl_get(struct snd_kcontrol *kctl, 
		if (err < 0)

			goto unlock;

	}

	ucontrol->value.enumerated.item[0] = private->level_switch[index];

	ucontrol->value.enumerated.item[0] = scarlett2_decode_muteable(

		private->level_switch[index]);



unlock:

	mutex_unlock(&private->data_mutex);
@@ -2831,6 +2848,10 @@ static int scarlett2_level_enum_ctl_put(struct snd_kcontrol *kctl, 


	private->level_switch[index] = val;



	/* To set the Gen 4 muteable controls, bit 1 gets set instead */

	if (private->config_set->items[SCARLETT2_CONFIG_LEVEL_SWITCH].mute)

		val = (!val) | 0x02;



	/* Send switch change to the device */

	err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_LEVEL_SWITCH,

				       index, val);
@@ -3078,8 +3099,8 @@ static int scarlett2_phantom_ctl_get(struct snd_kcontrol *kctl, 
		if (err < 0)

			goto unlock;

	}

	ucontrol->value.integer.value[0] =

		private->phantom_switch[elem->control];

	ucontrol->value.integer.value[0] = scarlett2_decode_muteable(

		private->phantom_switch[elem->control]);



unlock:

	mutex_unlock(&private->data_mutex);
@@ -3112,6 +3133,10 @@ static int scarlett2_phantom_ctl_put(struct snd_kcontrol *kctl, 


	private->phantom_switch[index] = val;



	/* To set the Gen 4 muteable controls, bit 1 gets set */

	if (private->config_set->items[SCARLETT2_CONFIG_PHANTOM_SWITCH].mute)

		val = (!val) | 0x02;



	/* Send switch change to the device */

	err = scarlett2_usb_set_config(mixer, SCARLETT2_CONFIG_PHANTOM_SWITCH,

				       index + info->phantom_first, val);