}
EXPORT_SYMBOL(snd_sof_set_d0_substate);
+/*
+ * Audio DSP states may transform as below:-
+ *
+ * D0I3 compatible stream
+ * Runtime +---------------------+ opened only, timeout
+ * suspend | +--------------------+
+ * +------------+ D0(active) | |
+ * | | <---------------+ |
+ * | +--------> | | |
+ * | |Runtime +--^--+---------^--+--+ The last | |
+ * | |resume | | | | opened D0I3 | |
+ * | | | | | | compatible | |
+ * | | resume| | | | stream closed | |
+ * | | from | | D3 | | | |
+ * | | D3 | |suspend | | d0i3 | |
+ * | | | | | |suspend | |
+ * | | | | | | | |
+ * | | | | | | | |
+ * +-v---+-----------+--v-------+ | | +------+----v----+
+ * | | | +-----------> |
+ * | D3 (suspended) | | | D0I3 +-----+
+ * | | +--------------+ | |
+ * | | resume from | | |
+ * +-------------------^--------+ d0i3 suspend +----------------+ |
+ * | |
+ * | D3 suspend |
+ * +------------------------------------------------+
+ *
+ * d0i3_suspend = s0_suspend && D0I3 stream opened,
+ * D3 suspend = !d0i3_suspend,
+ */
+
int snd_sof_resume(struct device *dev)
{
struct snd_sof_dev *sdev = dev_get_drvdata(dev);