ASoC: simple-card-utils: add asoc_simple_parse_pin_switches()

This function is a helper that permits to create pin switch controls for
a list of widgets whose names are listed in the PREFIX "pin-switches"
devicetree property.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 57 insertions, 0 deletions

diff --git a/sound/soc/generic/simple-card-utils.c b/sound/soc/generic/simple-card-utils.c
index db1458a19985..f4c6375d11c7 100644
--- a/sound/soc/generic/simple-card-utils.c
+++ b/sound/soc/generic/simple-card-utils.c
@@ -430,6 +430,63 @@ int asoc_simple_parse_widgets(struct snd_soc_card *card,
 }
 EXPORT_SYMBOL_GPL(asoc_simple_parse_widgets);
 
+int asoc_simple_parse_pin_switches(struct snd_soc_card *card,
+                                   char *prefix)
+{
+        const unsigned int nb_controls_max = 16;
+        const char **strings, *control_name;
+        struct snd_kcontrol_new *controls;
+        struct device *dev = card->dev;
+        unsigned int i, nb_controls;
+        char prop[128];
+        int ret;
+
+        if (!prefix)
+                prefix = "";
+
+        snprintf(prop, sizeof(prop), "%s%s", prefix, "pin-switches");
+
+        if (!of_property_read_bool(dev->of_node, prop))
+                return 0;
+
+        strings = devm_kcalloc(dev, nb_controls_max,
+                               sizeof(*strings), GFP_KERNEL);
+        if (!strings)
+                return -ENOMEM;
+
+        ret = of_property_read_string_array(dev->of_node, prop,
+                                            strings, nb_controls_max);
+        if (ret < 0)
+                return ret;
+
+        nb_controls = (unsigned int)ret;
+
+        controls = devm_kcalloc(dev, nb_controls,
+                                sizeof(*controls), GFP_KERNEL);
+        if (!controls)
+                return -ENOMEM;
+
+        for (i = 0; i < nb_controls; i++) {
+                control_name = devm_kasprintf(dev, GFP_KERNEL,
+                                              "%s Switch", strings[i]);
+                if (!control_name)
+                        return -ENOMEM;
+
+                controls[i].iface = SNDRV_CTL_ELEM_IFACE_MIXER;
+                controls[i].name = control_name;
+                controls[i].info = snd_soc_dapm_info_pin_switch;
+                controls[i].get = snd_soc_dapm_get_pin_switch;
+                controls[i].put = snd_soc_dapm_put_pin_switch;
+                controls[i].private_value = (unsigned long)strings[i];
+        }
+
+        card->controls = controls;
+        card->num_controls = nb_controls;
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(asoc_simple_parse_pin_switches);
+
 int asoc_simple_init_jack(struct snd_soc_card *card,
                           struct asoc_simple_jack *sjack,
                           int is_hp, char *prefix)