ALSA: x86: intel_hdmi_audio: enable pm_runtime and set autosuspend delay

The existing code uses pm_runtime_get_sync/put_autosuspend, but
pm_runtime was not explicitly enabled. The autosuspend delay was not
set either, the value is set to 5s since HDMI is rather painful to
resume.

Signed-off-by: Pierre-Louis Bossart <[e-mail]>
Reviewed-by: Bard Liao <[e-mail]>
Reviewed-by: Kai Vehmanen <[e-mail]>
Reviewed-by: Ranjani Sridharan <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Takashi Iwai <[e-mail]>

sound/x86/intel_hdmi_audio.c

···
 #include <drm/intel_lpe_audio.h>
 #include "intel_hdmi_audio.h"
 
+#define INTEL_HDMI_AUDIO_SUSPEND_DELAY_MS  5000
+
 #define for_each_pipe(card_ctx, pipe) \
 	for ((pipe) = 0; (pipe) < (card_ctx)->num_pipes; (pipe)++)
 #define for_each_port(card_ctx, port) \
···
 	pdata->notify_audio_lpe = notify_audio_lpe;
 	spin_unlock_irq(&pdata->lpe_audio_slock);
 
+	pm_runtime_set_autosuspend_delay(&pdev->dev, INTEL_HDMI_AUDIO_SUSPEND_DELAY_MS);
 	pm_runtime_use_autosuspend(&pdev->dev);
+	pm_runtime_enable(&pdev->dev);
 	pm_runtime_mark_last_busy(&pdev->dev);
+	pm_runtime_idle(&pdev->dev);
 
 	dev_dbg(&pdev->dev, "%s: handle pending notification\n", __func__);
 	for_each_port(card_ctx, port) {