Re: [PATCH v2 12/19] media: imx: Add SMFC subdev driver

This is a media entity subdevice driver for the i.MX Sensor Multi-FIFO
Controller module. Video frames are received from the CSI and can
be routed to various sinks including the i.MX Image Converter for
scaling, color-space conversion, motion compensated deinterlacing,
and image rotation.

Signed-off-by: Steve Longerbeam <redacted>
---
 drivers/staging/media/imx/Makefile   |   1 +
 drivers/staging/media/imx/imx-smfc.c | 739 +++++++++++++++++++++++++++++++++++
 2 files changed, 740 insertions(+)
 create mode 100644 drivers/staging/media/imx/imx-smfc.c

diff --git a/drivers/staging/media/imx/Makefile b/drivers/staging/media/imx/Makefile
index 133672a..3559d7b 100644
--- a/drivers/staging/media/imx/Makefile
+++ b/drivers/staging/media/imx/Makefile

@@ -5,4 +5,5 @@ obj-$(CONFIG_VIDEO_IMX_MEDIA) += imx-media.o
 obj-$(CONFIG_VIDEO_IMX_MEDIA) += imx-media-common.o
 
 obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-csi.o
+obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-smfc.o

diff --git a/drivers/staging/media/imx/imx-smfc.c b/drivers/staging/media/imx/imx-smfc.c
new file mode 100644
index 0000000..565048c
--- /dev/null
+++ b/drivers/staging/media/imx/imx-smfc.c

@@ -0,0 +1,739 @@
+/*
+ * V4L2 Capture SMFC Subdev for Freescale i.MX5/6 SOC
+ *
+ * This subdevice handles capture of raw/unconverted video frames
+ * from the CSI, directly to memory via the Sensor Multi-FIFO Controller.
+ *
+ * Copyright (c) 2012-2016 Mentor Graphics Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/timer.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+#include <linux/pinctrl/consumer.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-dma-contig.h>
+#include <media/v4l2-subdev.h>
+#include <media/v4l2-of.h>
+#include <media/v4l2-ctrls.h>

+#include <media/imx.h>
+#include "imx-media.h"
+

+static irqreturn_t imx_smfc_eof_interrupt(int irq, void *dev_id)
+{
+	struct imx_smfc_priv *priv = dev_id;
+	struct imx_media_dma_buf *done, *next;
+	unsigned long flags;
+
+	spin_lock_irqsave(&priv->irqlock, flags);

+
+	if (priv->last_eof) {
+		complete(&priv->last_eof_comp);
+		priv->last_eof = false;
+		goto unlock;
+	}
+
+	/* inform CSI of this EOF so it can monitor frame intervals */
+	v4l2_subdev_call(priv->src_sd, core, interrupt_service_routine,
+			 0, NULL);
+
+	done = imx_media_dma_buf_get_active(priv->out_ring);
+	/* give the completed buffer to the sink  */
+	if (!WARN_ON(!done))
+		imx_media_dma_buf_done(done, IMX_MEDIA_BUF_STATUS_DONE);
+
+	/* priv->next buffer is now the active one */
+	imx_media_dma_buf_set_active(priv->next);
+
+	/* bump the EOF timeout timer */
+	mod_timer(&priv->eof_timeout_timer,
+		  jiffies + msecs_to_jiffies(IMX_MEDIA_EOF_TIMEOUT));
+
+	if (ipu_idmac_buffer_is_ready(priv->smfc_ch, priv->ipu_buf_num))
+		ipu_idmac_clear_buffer(priv->smfc_ch, priv->ipu_buf_num);
+
+	/* get next queued buffer */
+	next = imx_media_dma_buf_get_next_queued(priv->out_ring);
+
+	ipu_cpmem_set_buffer(priv->smfc_ch, priv->ipu_buf_num, next->phys);
+	ipu_idmac_select_buffer(priv->smfc_ch, priv->ipu_buf_num);
+
+	/* toggle IPU double-buffer index */
+	priv->ipu_buf_num ^= 1;
+	priv->next = next;
+
+unlock:
+	spin_unlock_irqrestore(&priv->irqlock, flags);
+	return IRQ_HANDLED;
+}
+

+
+static const struct platform_device_id imx_smfc_ids[] = {
+	{ .name = "imx-ipuv3-smfc" },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, imx_smfc_ids);
+
+static struct platform_driver imx_smfc_driver = {
+	.probe = imx_smfc_probe,
+	.remove = imx_smfc_remove,
+	.id_table = imx_smfc_ids,
+	.driver = {
+		.name = "imx-ipuv3-smfc",
+		.owner = THIS_MODULE,

+	},
+};
+module_platform_driver(imx_smfc_driver);
+
+MODULE_DESCRIPTION("i.MX SMFC subdev driver");
+MODULE_AUTHOR("Steve Longerbeam <steve_longerbeam@mentor.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:imx-ipuv3-smfc");