ASoC: Add jack_status_check callback function for GPIO jacks

The jack_status_check callback function is the interface to check the
status of the jack. Some target provides the method to distinguish what
is the jack inserted - headphone jack, microphone jack, tvout jack, etc,
so we can implement it using the jack_status_check function.
Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

include/sound/soc.h

@@ -332,6 +332,8 @@ struct snd_soc_jack_gpio {
 	int debounce_time;
 	struct snd_soc_jack *jack;
 	struct work_struct work;
+
+	int (*jack_status_check)(void);
 };
 #endif
 

sound/soc/soc-jack.c

@@ -163,6 +163,9 @@ static void snd_soc_jack_gpio_detect(struct snd_soc_jack_gpio *gpio)
 	else
 		report = 0;
 
+	if (gpio->jack_status_check)
+		report = gpio->jack_status_check();
+
 	snd_soc_jack_report(jack, report, gpio->report);
 }