ALSA: dummy: Add customizable volume min/max.

Add module parameters to support customized min/max volume leveling,
which will be useful to test devices with different volume granularity.

Signed-off-by: YJ Lee <yunjunlee@chromium.org>
Link: https://lore.kernel.org/r/20220912072945.760949-1-yunjunlee@chromium.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/drivers/dummy.c b/sound/drivers/dummy.c
index fcf1ee00bd2146b3633be58a7f80cdc66d29e26b..9c17b49a2ae1c98d06a2f8ec9d434b638e698948 100644 (file)
--- a/sound/drivers/dummy.c
+++ b/sound/drivers/dummy.c
@@ -42,6 +42,8 @@ MODULE_LICENSE("GPL");
 #define USE_CHANNELS_MAX       2
 #define USE_PERIODS_MIN        1
 #define USE_PERIODS_MAX        1024
+#define USE_MIXER_VOLUME_LEVEL_MIN     -50
+#define USE_MIXER_VOLUME_LEVEL_MAX     100
 
 static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;     /* Index 0-MAX */
 static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;      /* ID for this card */
@@ -50,6 +52,8 @@ static char *model[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = NULL};
 static int pcm_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 1};
 static int pcm_substreams[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 8};
 //static int midi_devs[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = 2};
+static int mixer_volume_level_min = USE_MIXER_VOLUME_LEVEL_MIN;
+static int mixer_volume_level_max = USE_MIXER_VOLUME_LEVEL_MAX;
 #ifdef CONFIG_HIGH_RES_TIMERS
 static bool hrtimer = 1;
 #endif
@@ -69,6 +73,10 @@ module_param_array(pcm_substreams, int, NULL, 0444);
 MODULE_PARM_DESC(pcm_substreams, "PCM substreams # (1-128) for dummy driver.");
 //module_param_array(midi_devs, int, NULL, 0444);
 //MODULE_PARM_DESC(midi_devs, "MIDI devices # (0-2) for dummy driver.");
+module_param(mixer_volume_level_min, int, 0444);
+MODULE_PARM_DESC(mixer_volume_level_min, "Minimum mixer volume level for dummy driver. Default: -50");
+module_param(mixer_volume_level_max, int, 0444);
+MODULE_PARM_DESC(mixer_volume_level_max, "Maximum mixer volume level for dummy driver. Default: 100");
 module_param(fake_buffer, bool, 0444);
 MODULE_PARM_DESC(fake_buffer, "Fake buffer allocations.");
 #ifdef CONFIG_HIGH_RES_TIMERS
@@ -713,8 +721,8 @@ static int snd_dummy_volume_info(struct snd_kcontrol *kcontrol,
 {
        uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
        uinfo->count = 2;
-       uinfo->value.integer.min = -50;
-       uinfo->value.integer.max = 100;
+       uinfo->value.integer.min = mixer_volume_level_min;
+       uinfo->value.integer.max = mixer_volume_level_max;
        return 0;
 }
 
@@ -739,15 +747,15 @@ static int snd_dummy_volume_put(struct snd_kcontrol *kcontrol,
        int left, right;
 
        left = ucontrol->value.integer.value[0];
-       if (left < -50)
-               left = -50;
-       if (left > 100)
-               left = 100;
+       if (left < mixer_volume_level_min)
+               left = mixer_volume_level_min;
+       if (left > mixer_volume_level_max)
+               left = mixer_volume_level_max;
        right = ucontrol->value.integer.value[1];
-       if (right < -50)
-               right = -50;
-       if (right > 100)
-               right = 100;
+       if (right < mixer_volume_level_min)
+               right = mixer_volume_level_min;
+       if (right > mixer_volume_level_max)
+               right = mixer_volume_level_max;
        spin_lock_irq(&dummy->mixer_lock);
        change = dummy->mixer_volume[addr][0] != left ||
                 dummy->mixer_volume[addr][1] != right;
@@ -1076,6 +1084,12 @@ static int snd_dummy_probe(struct platform_device *devptr)
                        dummy->pcm_hw.channels_max = m->channels_max;
        }
 
+       if (mixer_volume_level_min > mixer_volume_level_max) {
+               pr_warn("snd-dummy: Invalid mixer volume level: min=%d, max=%d. Fall back to default value.\n",
+               mixer_volume_level_min, mixer_volume_level_max);
+               mixer_volume_level_min = USE_MIXER_VOLUME_LEVEL_MIN;
+               mixer_volume_level_max = USE_MIXER_VOLUME_LEVEL_MAX;
+       }
        err = snd_card_dummy_new_mixer(dummy);
        if (err < 0)
                return err;