[media] adv7180: Add fast switch support

In fast switch mode the adv7180 (and similar) can lock onto a new signal
faster when switching between different inputs. As a downside though it is
no longer able to auto-detect the incoming format.

The fast switch mode is exposed as a boolean v4l control that allows
userspace applications to either enable or disable fast switch mode.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Federico Vaga <federico.vaga@gmail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/i2c/adv7180.c

@@ -127,6 +127,9 @@
 #define ADV7180_REG_VPP_SLAVE_ADDR	0xFD
 #define ADV7180_REG_CSI_SLAVE_ADDR	0xFE
 
+#define ADV7180_REG_FLCONTROL 0x40e0
+#define ADV7180_FLCONTROL_FL_ENABLE 0x1
+
 #define ADV7180_CSI_REG_PWRDN	0x00
 #define ADV7180_CSI_PWRDN	0x80
 
@@ -164,6 +167,8 @@
 #define ADV7180_DEFAULT_CSI_I2C_ADDR 0x44
 #define ADV7180_DEFAULT_VPP_I2C_ADDR 0x42
 
+#define V4L2_CID_ADV_FAST_SWITCH	(V4L2_CID_USER_ADV7180_BASE + 0x00)
+
 struct adv7180_state;
 
 #define ADV7180_FLAG_RESET_POWERED	BIT(0)
@@ -508,6 +513,18 @@ static int adv7180_s_ctrl(struct v4l2_ctrl *ctrl)
 			break;
 		ret = adv7180_write(state, ADV7180_REG_SD_SAT_CR, val);
 		break;
+	case V4L2_CID_ADV_FAST_SWITCH:
+		if (ctrl->val) {
+			/* ADI required write */
+			adv7180_write(state, 0x80d9, 0x44);
+			adv7180_write(state, ADV7180_REG_FLCONTROL,
+				ADV7180_FLCONTROL_FL_ENABLE);
+		} else {
+			/* ADI required write */
+			adv7180_write(state, 0x80d9, 0xc4);
+			adv7180_write(state, ADV7180_REG_FLCONTROL, 0x00);
+		}
+		break;
 	default:
 		ret = -EINVAL;
 	}
@@ -520,6 +537,16 @@ static const struct v4l2_ctrl_ops adv7180_ctrl_ops = {
 	.s_ctrl = adv7180_s_ctrl,
 };
 
+static const struct v4l2_ctrl_config adv7180_ctrl_fast_switch = {
+	.ops = &adv7180_ctrl_ops,
+	.id = V4L2_CID_ADV_FAST_SWITCH,
+	.name = "Fast Switching",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = 0,
+	.max = 1,
+	.step = 1,
+};
+
 static int adv7180_init_controls(struct adv7180_state *state)
 {
 	v4l2_ctrl_handler_init(&state->ctrl_hdl, 4);
@@ -536,6 +563,8 @@ static int adv7180_init_controls(struct adv7180_state *state)
 	v4l2_ctrl_new_std(&state->ctrl_hdl, &adv7180_ctrl_ops,
 			  V4L2_CID_HUE, ADV7180_HUE_MIN,
 			  ADV7180_HUE_MAX, 1, ADV7180_HUE_DEF);
+	v4l2_ctrl_new_custom(&state->ctrl_hdl, &adv7180_ctrl_fast_switch, NULL);
+
 	state->sd.ctrl_handler = &state->ctrl_hdl;
 	if (state->ctrl_hdl.error) {
 		int err = state->ctrl_hdl.error;

include/uapi/linux/v4l2-controls.h

@@ -170,6 +170,10 @@ enum v4l2_colorfx {
  * We reserve 16 controls for this driver. */
 #define V4L2_CID_USER_SAA7134_BASE		(V4L2_CID_USER_BASE + 0x1060)
 
+/* The base for the adv7180 driver controls.
+ * We reserve 16 controls for this driver. */
+#define V4L2_CID_USER_ADV7180_BASE		(V4L2_CID_USER_BASE + 0x1070)
+
 /* MPEG-class control IDs */
 /* The MPEG controls are applicable to all codec controls
  * and the 'MPEG' part of the define is historical */