crypto: omap-sham - do not schedule tasklet if there is no active requests

Signed-off-by: Dmitry Kasatkin <[e-mail]>
Signed-off-by: Herbert Xu <[e-mail]>

drivers/crypto/omap-sham.c

···
 				 SHA_REG_CTRL_OUTPUT_READY);
 	omap_sham_read(dd, SHA_REG_CTRL);
 
+	if (!test_bit(FLAGS_BUSY, &dd->flags)) {
+		dev_warn(dd->dev, "Interrupt when no active requests.\n");
+		return IRQ_HANDLED;
+	}
+
 	set_bit(FLAGS_OUTPUT_READY, &dd->flags);
 	tasklet_schedule(&dd->done_task);