ReferenceClock interface

drivers/video/mxc/mxc_dcic.c

@@ -59,6 +59,11 @@
 #define FB_SYNC_OE_LOW_ACT		0x80000000
 #define FB_SYNC_CLK_LAT_FALL	0x40000000
 
+static wait_queue_head_t mxc_dcic_wait;
+static int mxc_dcic_vsync;
+static int mxc_dcic_irq;
+static unsigned long mxc_dcic_counter;
+
 static const struct dcic_mux imx6q_dcic0_mux[] = {
 	{
 		.dcic = DCIC_IPU1_DI0,
@@ -238,13 +243,13 @@ static bool roi_configure(struct dcic_data *dcic, struct roi_params *roi_param)
 	u32 val;
 
 	if (roi_param->roi_n < 0 || roi_param->roi_n >= 16) {
-		printk(KERN_ERR "Error, Wrong ROI number %d\n", roi_param->roi_n);
+		pr_err("Error, Wrong ROI number %d\n", roi_param->roi_n);
 		return false;
 	}
 
 	if (roi_param->end_x <= roi_param->start_x ||
 			roi_param->end_y <= roi_param->start_y) {
-		printk(KERN_ERR "Error, Wrong ROI\n");
+		pr_err("Error, Wrong ROI\n");
 		return false;
 	}
 
@@ -297,20 +302,30 @@ static irqreturn_t dcic_irq_handler(int irq, void *data)
 
 	dcic->result = dcics & 0xffff;
 
-	dcic_int_disable(dcic);
+	if (!mxc_dcic_vsync)
+		dcic_int_disable(dcic);
+	else {
+		mxc_dcic_irq = 1;
+		mxc_dcic_counter++;
+	}
 
 	/* clean dcic interrupt state */
 	writel(DCICS_FI_STAT_PENDING, &dcic->regs->dcics);
 	writel(dcics, &dcic->regs->dcics);
 
+	if (mxc_dcic_vsync) {
+		wake_up(&mxc_dcic_wait);
+		return IRQ_HANDLED;
+	}
+
 	for (i = 0; i < 16; i++) {
-		printk(KERN_INFO "ROI=%d,crcRS=0x%x, crcCS=0x%x\n", i,
+		pr_debug("ROI=%d,crcRS=0x%x, crcCS=0x%x\n", i,
 				readl(&dcic->regs->ROI[i].dcicrrs),
 				readl(&dcic->regs->ROI[i].dcicrcs));
 	}
 	complete(&dcic->roi_crc_comp);
 
-	return 0;
+	return IRQ_HANDLED;
 }
 
 static int dcic_configure(struct dcic_data *dcic, unsigned int sync)
@@ -371,7 +386,7 @@ static int dcic_init(struct device_node *np, struct dcic_data *dcic)
 
 	val = of_get_dcic_val(np, dcic);
 	if (val < 0) {
-		printk(KERN_ERR "Error incorrect\n");
+		pr_err("Error incorrect\n");
 		return -1;
 	}
 
@@ -427,19 +442,64 @@ static long dcic_ioctl(struct file *file,
 		}
 		dcic_disable(dcic);
 		break;
+	case DCIC_IOC_START_VSYNC:
+		mxc_dcic_vsync = 1;
+		mxc_dcic_irq = 0;
+		mxc_dcic_counter = 0;
+
+		// configure minimum roi block
+		roi_param.roi_n = 0;
+		roi_param.end_x = 1;
+		roi_param.start_x = 0;
+		roi_param.end_y = 1;
+		roi_param.start_y = 0;
+		roi_configure(dcic, &roi_param);
+
+		dcic_enable(dcic);
+		dcic_int_enable(dcic);
+		break;
+	case DCIC_IOC_STOP_VSYNC:
+		mxc_dcic_vsync = 0;
+		mxc_dcic_irq = 0;
+		init_completion(&dcic->roi_crc_comp);
+		wait_for_completion_interruptible_timeout(&dcic->roi_crc_comp, 1 * HZ);
+		dcic_disable(dcic);
+		break;
 	default:
-		printk(KERN_ERR "%s, Unsupport cmd %d\n", __func__, cmd);
+		pr_err("%s, Unsupport cmd %d\n", __func__, cmd);
 		break;
      }
      return ret;
 }
 
+static ssize_t dcic_read(struct file *file, char __user *buf, size_t count,
+			    loff_t *ppos)
+{
+	int ret = 0;
+
+	do {
+		if (mxc_dcic_irq) {
+			count = min(sizeof(unsigned long), count);
+			ret = copy_to_user(buf, &mxc_dcic_counter, count) ? -EFAULT : count;
+			mxc_dcic_irq = 0;
+			break;
+		}
+		if (file->f_flags & O_NONBLOCK) {
+			ret = -EAGAIN;
+		}
+		else if (wait_event_interruptible(mxc_dcic_wait, mxc_dcic_irq))
+			ret = -ERESTARTSYS;
+	} while(!ret);
+
+	return ret;
+}
 
 static const struct file_operations mxc_dcic_fops = {
 	.owner = THIS_MODULE,
 	.open = dcic_open,
 	.release = dcic_release,
 	.unlocked_ioctl = dcic_ioctl,
+	.read = dcic_read,
 };
 
 static int dcic_probe(struct platform_device *pdev)
@@ -510,15 +570,15 @@ static int dcic_probe(struct platform_device *pdev)
 	mutex_init(&dcic->lock);
 	ret = dcic_init(np, dcic);
 	if (ret < 0) {
-		printk(KERN_ERR "Failed init dcic\n");
+		pr_err("Failed init dcic\n");
 		goto ealloc;
 	}
 
 	/* register device */
 	name = dcic->buses[dcic->bus_n].name;
 	dcic->major = register_chrdev(0, name, &mxc_dcic_fops);
 	if (dcic->major < 0) {
-		printk(KERN_ERR "DCIC: unable to get a major for dcic\n");
+		pr_err("DCIC: unable to get a major for dcic\n");
 		ret = -EBUSY;
 		goto ealloc;
 	}
@@ -553,6 +613,10 @@ static int dcic_probe(struct platform_device *pdev)
 		goto err_out_cdev;
 	}
 
+	init_waitqueue_head(&mxc_dcic_wait);
+	mxc_dcic_vsync = 0;
+	mxc_dcic_irq = 0;
+
 	return 0;
 
 err_out_cdev:

include/uapi/linux/Kbuild

@@ -257,6 +257,8 @@ header-y += msg.h
 header-y += mtio.h
 header-y += mxcfb.h
 header-y += mxc_v4l2.h
+header-y += mxc_dcic.h
+header-y += ipu.h
 header-y += n_r3964.h
 header-y += nbd.h
 header-y += ncp.h

include/uapi/linux/mxc_dcic.h

@@ -33,6 +33,8 @@
 #define DCIC_IOC_CONFIG_DCIC	_IO('D', 12)
 #define DCIC_IOC_CONFIG_ROI		_IO('D', 13)
 #define DCIC_IOC_GET_RESULT		_IO('D', 14)
+#define DCIC_IOC_START_VSYNC		_IO('D', 15)
+#define DCIC_IOC_STOP_VSYNC		_IO('D', 16)
 
 struct roi_params {
 	unsigned int roi_n;