V4L/DVB (7451): cx88: Add user control for chroma AGC

The cx2388x family has support for chroma AGC. This patch implements a
the V4L2_CID_CHROMA_AGC control for the cx2388x family. By default
chroma AGC is disabled, as in previous versions of the driver.

Signed-off-by: "Frej Drejhammar <frej.drejhammar@gmail.com>"
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/cx88/cx88-blackbird.c

@@ -693,7 +693,7 @@ static int blackbird_queryctrl(struct cx8802_dev *dev, struct v4l2_queryctrl *qc
 		return -EINVAL;
 
 	/* Standard V4L2 controls */
-	if (cx8800_ctrl_query(qctrl) == 0)
+	if (cx8800_ctrl_query(dev->core, qctrl) == 0)
 		return 0;
 
 	/* MPEG V4L2 controls */
@@ -933,7 +933,7 @@ static int vidioc_queryctrl (struct file *file, void *priv,
 	qctrl->id = v4l2_ctrl_next(ctrl_classes, qctrl->id);
 	if (unlikely(qctrl->id == 0))
 		return -EINVAL;
-	return cx8800_ctrl_query(qctrl);
+	return cx8800_ctrl_query(dev->core, qctrl);
 }
 
 static int vidioc_enum_input (struct file *file, void *priv,

drivers/media/video/cx88/cx88-core.c

@@ -929,6 +929,10 @@ int cx88_set_tvnorm(struct cx88_core *core, v4l2_std_id norm)
 
 	dprintk(1,"set_tvnorm: MO_INPUT_FORMAT  0x%08x [old=0x%08x]\n",
 		cxiformat, cx_read(MO_INPUT_FORMAT) & 0x0f);
+	/* Chroma AGC must be disabled if SECAM is used */
+	if (norm & V4L2_STD_SECAM)
+		cx_andor(MO_INPUT_FORMAT, 0x40f, cxiformat);
+	else
 		cx_andor(MO_INPUT_FORMAT, 0xf, cxiformat);
 
 	// FIXME: as-is from DScaler

drivers/media/video/cx88/cx88-video.c

@@ -228,6 +228,18 @@ static struct cx88_ctrl cx8800_ctls[] = {
 		.mask                  = 0x00ff,
 		.shift                 = 0,
 	},{
+		.v = {
+			.id            = V4L2_CID_CHROMA_AGC,
+			.name          = "Chroma AGC",
+			.minimum       = 0,
+			.maximum       = 1,
+			.default_value = 0x0,
+			.type          = V4L2_CTRL_TYPE_BOOLEAN,
+		},
+		.reg                   = MO_INPUT_FORMAT,
+		.mask                  = 1 << 10,
+		.shift                 = 10,
+	}, {
 	/* --- audio --- */
 		.v = {
 			.id            = V4L2_CID_AUDIO_MUTE,
@@ -282,6 +294,7 @@ const u32 cx88_user_ctrls[] = {
 	V4L2_CID_AUDIO_VOLUME,
 	V4L2_CID_AUDIO_BALANCE,
 	V4L2_CID_AUDIO_MUTE,
+	V4L2_CID_CHROMA_AGC,
 	0
 };
 EXPORT_SYMBOL(cx88_user_ctrls);
@@ -291,7 +304,7 @@ static const u32 *ctrl_classes[] = {
 	NULL
 };
 
-int cx8800_ctrl_query(struct v4l2_queryctrl *qctrl)
+int cx8800_ctrl_query(struct cx88_core *core, struct v4l2_queryctrl *qctrl)
 {
 	int i;
 
@@ -306,6 +319,11 @@ int cx8800_ctrl_query(struct v4l2_queryctrl *qctrl)
 		return 0;
 	}
 	*qctrl = cx8800_ctls[i].v;
+	/* Report chroma AGC as inactive when SECAM is selected */
+	if (cx8800_ctls[i].v.id == V4L2_CID_CHROMA_AGC &&
+	    core->tvnorm & V4L2_STD_SECAM)
+		qctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
+
 	return 0;
 }
 EXPORT_SYMBOL(cx8800_ctrl_query);
@@ -976,6 +994,12 @@ int cx88_set_control(struct cx88_core *core, struct v4l2_control *ctl)
 		}
 		mask=0xffff;
 		break;
+	case V4L2_CID_CHROMA_AGC:
+		/* Do not allow chroma AGC to be enabled for SECAM */
+		value = ((ctl->value - c->off) << c->shift) & c->mask;
+		if (core->tvnorm & V4L2_STD_SECAM && value)
+			return -EINVAL;
+		break;
 	default:
 		value = ((ctl->value - c->off) << c->shift) & c->mask;
 		break;
@@ -1268,10 +1292,12 @@ static int vidioc_s_input (struct file *file, void *priv, unsigned int i)
 static int vidioc_queryctrl (struct file *file, void *priv,
 				struct v4l2_queryctrl *qctrl)
 {
+	struct cx88_core *core = ((struct cx8800_fh *)priv)->dev->core;
+
 	qctrl->id = v4l2_ctrl_next(ctrl_classes, qctrl->id);
 	if (unlikely(qctrl->id == 0))
 		return -EINVAL;
-	return cx8800_ctrl_query(qctrl);
+	return cx8800_ctrl_query(core, qctrl);
 }
 
 static int vidioc_g_ctrl (struct file *file, void *priv,

drivers/media/video/cx88/cx88.h

@@ -651,7 +651,8 @@ void cx8802_cancel_buffers(struct cx8802_dev *dev);
 /* ----------------------------------------------------------- */
 /* cx88-video.c*/
 extern const u32 cx88_user_ctrls[];
-extern int cx8800_ctrl_query(struct v4l2_queryctrl *qctrl);
+extern int cx8800_ctrl_query(struct cx88_core *core,
+			     struct v4l2_queryctrl *qctrl);
 int cx88_enum_input (struct cx88_core  *core,struct v4l2_input *i);
 int cx88_set_freq (struct cx88_core  *core,struct v4l2_frequency *f);
 int cx88_get_control(struct cx88_core *core, struct v4l2_control *ctl);