ASoC: Intel: Headset button support in broxton machine driver

Map the 4 headset buttons to KEY_PAUSE, KEY_VOLUMEUP, KEY_VOLUMEDOWN and
KEY_VOICECOMMAND.
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Naveen Manohar <naveen.m@intel.com>
Signed-off-by: Yong Zhi <yong.zhi@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/boards/bxt_da7219_max98357a.c

@@ -16,6 +16,7 @@
  * GNU General Public License for more details.
  */
 
+#include <linux/input.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <sound/core.h>
@@ -193,6 +194,12 @@ static int broxton_da7219_codec_init(struct snd_soc_pcm_runtime *rtd)
 		return ret;
 	}
 
+	snd_jack_set_key(broxton_headset.jack, SND_JACK_BTN_0, KEY_PLAYPAUSE);
+	snd_jack_set_key(broxton_headset.jack, SND_JACK_BTN_1, KEY_VOLUMEUP);
+	snd_jack_set_key(broxton_headset.jack, SND_JACK_BTN_2, KEY_VOLUMEDOWN);
+	snd_jack_set_key(broxton_headset.jack, SND_JACK_BTN_3,
+			 KEY_VOICECOMMAND);
+
 	da7219_aad_jack_det(component, &broxton_headset);
 
 	snd_soc_dapm_ignore_suspend(&rtd->card->dapm, "SoC DMIC");