ASoC: add snd_soc_of_parse_audio_simple_widgets for DT

This patch adds snd_soc_of_parse_audio_simple_widgets() and supports
below style of widgets name on DT:

	"template-wname", "user supplied wname"

For instance:
	simple-audio-widgets =
		"Microphone", "Microphone Jack",
		"Line", "Line In Jack",
		"Line", "Line Out Jack",
		"Headphone", "Headphone Jack",
		"Speaker", "Speaker External";

The "template-wname" currently includes: "Microphone", "Line", "Headphone"
and "Speaker".

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 87 insertions, 0 deletions

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index fe1df50805a3..0540cb08e0ea 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -4417,6 +4417,93 @@ int snd_soc_of_parse_card_name(struct snd_soc_card *card,
 }
 EXPORT_SYMBOL_GPL(snd_soc_of_parse_card_name);
 
+static const struct snd_soc_dapm_widget simple_widgets[] = {
+        SND_SOC_DAPM_MIC("Microphone", NULL),
+        SND_SOC_DAPM_LINE("Line", NULL),
+        SND_SOC_DAPM_HP("Headphone", NULL),
+        SND_SOC_DAPM_SPK("Speaker", NULL),
+};
+
+int snd_soc_of_parse_audio_simple_widgets(struct snd_soc_card *card,
+                                          const char *propname)
+{
+        struct device_node *np = card->dev->of_node;
+        struct snd_soc_dapm_widget *widgets;
+        const char *template, *wname;
+        int i, j, num_widgets, ret;
+
+        num_widgets = of_property_count_strings(np, propname);
+        if (num_widgets < 0) {
+                dev_err(card->dev,
+                        "ASoC: Property '%s' does not exist\n", propname);
+                return -EINVAL;
+        }
+        if (num_widgets & 1) {
+                dev_err(card->dev,
+                        "ASoC: Property '%s' length is not even\n", propname);
+                return -EINVAL;
+        }
+
+        num_widgets /= 2;
+        if (!num_widgets) {
+                dev_err(card->dev, "ASoC: Property '%s's length is zero\n",
+                        propname);
+                return -EINVAL;
+        }
+
+        widgets = devm_kcalloc(card->dev, num_widgets, sizeof(*widgets),
+                               GFP_KERNEL);
+        if (!widgets) {
+                dev_err(card->dev,
+                        "ASoC: Could not allocate memory for widgets\n");
+                return -ENOMEM;
+        }
+
+        for (i = 0; i < num_widgets; i++) {
+                ret = of_property_read_string_index(np, propname,
+                        2 * i, &template);
+                if (ret) {
+                        dev_err(card->dev,
+                                "ASoC: Property '%s' index %d read error:%d\n",
+                                propname, 2 * i, ret);
+                        return -EINVAL;
+                }
+
+                for (j = 0; j < ARRAY_SIZE(simple_widgets); j++) {
+                        if (!strncmp(template, simple_widgets[j].name,
+                                     strlen(simple_widgets[j].name))) {
+                                widgets[i] = simple_widgets[j];
+                                break;
+                        }
+                }
+
+                if (j >= ARRAY_SIZE(simple_widgets)) {
+                        dev_err(card->dev,
+                                "ASoC: DAPM widget '%s' is not supported\n",
+                                template);
+                        return -EINVAL;
+                }
+
+                ret = of_property_read_string_index(np, propname,
+                                                    (2 * i) + 1,
+                                                    &wname);
+                if (ret) {
+                        dev_err(card->dev,
+                                "ASoC: Property '%s' index %d read error:%d\n",
+                                propname, (2 * i) + 1, ret);
+                        return -EINVAL;
+                }
+
+                widgets[i].name = wname;
+        }
+
+        card->dapm_widgets = widgets;
+        card->num_dapm_widgets = num_widgets;
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(snd_soc_of_parse_audio_simple_widgets);
+
 int snd_soc_of_parse_audio_routing(struct snd_soc_card *card,
                                    const char *propname)
 {