ASoC: rt5645: add sys clk detection

Add system clock detection to prevent output DC from SPO.

Signed-off-by: Bard Liao <bardliao@realtek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/rt5645.h b/sound/soc/codecs/rt5645.h
index 093e46d..205e071 100644
--- a/sound/soc/codecs/rt5645.h
+++ b/sound/soc/codecs/rt5645.h
@@ -2122,6 +2122,10 @@
 /* General Control3 (0xfc) */
 #define RT5645_JD_PSV_MODE			(0x1 << 12)
 #define RT5645_IRQ_CLK_GATE_CTRL		(0x1 << 11)
+#define RT5645_DET_CLK_MASK			(0x3 << 9)
+#define RT5645_DET_CLK_DIS			(0x0 << 9)
+#define RT5645_DET_CLK_MODE1			(0x1 << 9)
+#define RT5645_DET_CLK_MODE2			(0x2 << 9)
 #define RT5645_MICINDET_MANU			(0x1 << 7)
 #define RT5645_RING2_SLEEVE_GND			(0x1 << 5)