3 files changed, 35 insertions, 2 deletions
diff --git a/drivers/media/usb/stk1160/stk1160-ac97.c b/drivers/media/usb/stk1160/stk1160-ac97.c
index 502fc8ee9a97..5e9b76edd81c 100644
--- a/drivers/media/usb/stk1160/stk1160-ac97.c
+++ b/drivers/media/usb/stk1160/stk1160-ac97.c
@@ -91,8 +91,34 @@ void stk1160_ac97_dump_regs(struct stk1160 *dev)
 }
 #endif
 
+int stk1160_has_audio(struct stk1160 *dev)
+{
+	u8 value;
+
+	stk1160_read_reg(dev, STK1160_POSV_L, &value);
+	return !(value & STK1160_POSV_L_ACDOUT);
+}
+
+int stk1160_has_ac97(struct stk1160 *dev)
+{
+	u8 value;
+
+	stk1160_read_reg(dev, STK1160_POSV_L, &value);
+	return !(value & STK1160_POSV_L_ACSYNC);
+}
+
 void stk1160_ac97_setup(struct stk1160 *dev)
 {
+	if (!stk1160_has_audio(dev)) {
+		stk1160_info("Device doesn't support audio, skipping AC97 setup.");
+		return;
+	}
+
+	if (!stk1160_has_ac97(dev)) {
+		stk1160_info("Device uses internal 8-bit ADC, skipping AC97 setup.");
+		return;
+	}
+
 	/* Two-step reset AC97 interface and hardware codec */
 	stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x94);
 	stk1160_write_reg(dev, STK1160_AC97CTL_0, 0x8c);
diff --git a/drivers/media/usb/stk1160/stk1160-core.c b/drivers/media/usb/stk1160/stk1160-core.c
index f3c9b8a2c6e8..c86eb6164713 100644
--- a/drivers/media/usb/stk1160/stk1160-core.c
+++ b/drivers/media/usb/stk1160/stk1160-core.c
@@ -20,8 +20,7 @@
  *
  * TODO:
  *
- * 1. (Try to) detect if we must register ac97 mixer
- * 2. Support stream at lower speed: lower frame rate or lower frame size.
+ * 1. Support stream at lower speed: lower frame rate or lower frame size.
  *
  */
 
diff --git a/drivers/media/usb/stk1160/stk1160-reg.h b/drivers/media/usb/stk1160/stk1160-reg.h
index 81ff3a15d96e..296a9e712c81 100644
--- a/drivers/media/usb/stk1160/stk1160-reg.h
+++ b/drivers/media/usb/stk1160/stk1160-reg.h
@@ -26,6 +26,14 @@
 /* Remote Wakup Control */
 #define STK1160_RMCTL			0x00c
 
+/* Power-on Strapping Data */
+#define STK1160_POSVA			0x010
+#define STK1160_POSV_L			0x010
+#define STK1160_POSV_M			0x011
+#define STK1160_POSV_H			0x012
+#define  STK1160_POSV_L_ACDOUT		BIT(3)
+#define  STK1160_POSV_L_ACSYNC		BIT(2)
+
 /*
  * Decoder Control Register:
  * This byte controls capture start/stop