[media] media: platform: rcar_drif: Add DRIF support

This patch adds Digital Radio Interface (DRIF) support to R-Car Gen3 SoCs.
The driver exposes each instance of DRIF as a V4L2 SDR device. A DRIF
device represents a channel and each channel can have one or two
sub-channels respectively depending on the target board.

DRIF supports only Rx functionality. It receives samples from a RF
frontend tuner chip it is interfaced with. The combination of DRIF and the
tuner device, which is registered as a sub-device, determines the receive
sample rate and format.

In order to be compliant as a V4L2 SDR device, DRIF needs to bind with
the tuner device, which can be provided by a third party vendor. DRIF acts
as a slave device and the tuner device acts as a master transmitting the
samples. The driver allows asynchronous binding of a tuner device that
is registered as a v4l2 sub-device. The driver can learn about the tuner
it is interfaced with based on port endpoint properties of the device in
device tree. The V4L2 SDR device inherits the controls exposed by the
tuner device.

The device can also be configured to use either one or both of the data
pins at runtime based on the master (tuner) configuration.
Signed-off-by: Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/Kconfig

@@ -550,3 +550,28 @@ config VIDEO_STM32_HDMI_CEC
          between compatible devices.
 
 endif #CEC_PLATFORM_DRIVERS
+
+menuconfig SDR_PLATFORM_DRIVERS
+	bool "SDR platform devices"
+	depends on MEDIA_SDR_SUPPORT
+	default n
+	---help---
+	  Say Y here to enable support for platform-specific SDR Drivers.
+
+if SDR_PLATFORM_DRIVERS
+
+config VIDEO_RCAR_DRIF
+	tristate "Renesas Digitial Radio Interface (DRIF)"
+	depends on VIDEO_V4L2 && HAS_DMA
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select VIDEOBUF2_VMALLOC
+	---help---
+	  Say Y if you want to enable R-Car Gen3 DRIF support. DRIF is Digital
+	  Radio Interface that interfaces with an RF front end chip. It is a
+	  receiver of digital data which uses DMA to transfer received data to
+	  a configured location for an application to use.
+
+	  To compile this driver as a module, choose M here; the module
+	  will be called rcar_drif.
+
+endif # SDR_PLATFORM_DRIVERS

drivers/media/platform/Makefile

@@ -54,6 +54,7 @@ obj-$(CONFIG_VIDEO_SH_VOU)		+= sh_vou.o
 
 obj-$(CONFIG_SOC_CAMERA)		+= soc_camera/
 
+obj-$(CONFIG_VIDEO_RCAR_DRIF)		+= rcar_drif.o
 obj-$(CONFIG_VIDEO_RENESAS_FCP) 	+= rcar-fcp.o
 obj-$(CONFIG_VIDEO_RENESAS_FDP1)	+= rcar_fdp1.o
 obj-$(CONFIG_VIDEO_RENESAS_JPU) 	+= rcar_jpu.o

drivers/media/platform/rcar_drif.c

+/*
+ * R-Car Gen3 Digital Radio Interface (DRIF) driver
+ *
+ * Copyright (C) 2017 Renesas Electronics Corporation
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * The R-Car DRIF is a receive only MSIOF like controller with an
+ * external master device driving the SCK. It receives data into a FIFO,
+ * then this driver uses the SYS-DMAC engine to move the data from
+ * the device to memory.
+ *
+ * Each DRIF channel DRIFx (as per datasheet) contains two internal
+ * channels DRIFx0 & DRIFx1 within itself with each having its own resources
+ * like module clk, register set, irq and dma. These internal channels share
+ * common CLK & SYNC from master. The two data pins D0 & D1 shall be
+ * considered to represent the two internal channels. This internal split
+ * is not visible to the master device.
+ *
+ * Depending on the master device, a DRIF channel can use
+ *  (1) both internal channels (D0 & D1) to receive data in parallel (or)
+ *  (2) one internal channel (D0 or D1) to receive data
+ *
+ * The primary design goal of this controller is to act as a Digital Radio
+ * Interface that receives digital samples from a tuner device. Hence the
+ * driver exposes the device as a V4L2 SDR device. In order to qualify as
+ * a V4L2 SDR device, it should possess a tuner interface as mandated by the
+ * framework. This driver expects a tuner driver (sub-device) to bind
+ * asynchronously with this device and the combined drivers shall expose
+ * a V4L2 compliant SDR device. The DRIF driver is independent of the
+ * tuner vendor.
+ *
+ * The DRIF h/w can support I2S mode and Frame start synchronization pulse mode.
+ * This driver is tested for I2S mode only because of the availability of
+ * suitable master devices. Hence, not all configurable options of DRIF h/w
+ * like lsb/msb first, syncdl, dtdl etc. are exposed via DT and I2S defaults
+ * are used. These can be exposed later if needed after testing.
+ */
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/ioctl.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/of_graph.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-v4l2.h>
+#include <media/videobuf2-vmalloc.h>
+
+/* DRIF register offsets */
+#define RCAR_DRIF_SITMDR1			0x00
+#define RCAR_DRIF_SITMDR2			0x04
+#define RCAR_DRIF_SITMDR3			0x08
+#define RCAR_DRIF_SIRMDR1			0x10
+#define RCAR_DRIF_SIRMDR2			0x14
+#define RCAR_DRIF_SIRMDR3			0x18
+#define RCAR_DRIF_SICTR				0x28
+#define RCAR_DRIF_SIFCTR			0x30
+#define RCAR_DRIF_SISTR				0x40
+#define RCAR_DRIF_SIIER				0x44
+#define RCAR_DRIF_SIRFDR			0x60
+
+#define RCAR_DRIF_RFOVF			BIT(3)	/* Receive FIFO overflow */
+#define RCAR_DRIF_RFUDF			BIT(4)	/* Receive FIFO underflow */
+#define RCAR_DRIF_RFSERR		BIT(5)	/* Receive frame sync error */
+#define RCAR_DRIF_REOF			BIT(7)	/* Frame reception end */
+#define RCAR_DRIF_RDREQ			BIT(12) /* Receive data xfer req */
+#define RCAR_DRIF_RFFUL			BIT(13)	/* Receive FIFO full */
+
+/* SIRMDR1 */
+#define RCAR_DRIF_SIRMDR1_SYNCMD_FRAME		(0 << 28)
+#define RCAR_DRIF_SIRMDR1_SYNCMD_LR		(3 << 28)
+
+#define RCAR_DRIF_SIRMDR1_SYNCAC_POL_HIGH	(0 << 25)
+#define RCAR_DRIF_SIRMDR1_SYNCAC_POL_LOW	(1 << 25)
+
+#define RCAR_DRIF_SIRMDR1_MSB_FIRST		(0 << 24)
+#define RCAR_DRIF_SIRMDR1_LSB_FIRST		(1 << 24)
+
+#define RCAR_DRIF_SIRMDR1_DTDL_0		(0 << 20)
+#define RCAR_DRIF_SIRMDR1_DTDL_1		(1 << 20)
+#define RCAR_DRIF_SIRMDR1_DTDL_2		(2 << 20)
+#define RCAR_DRIF_SIRMDR1_DTDL_0PT5		(5 << 20)
+#define RCAR_DRIF_SIRMDR1_DTDL_1PT5		(6 << 20)
+
+#define RCAR_DRIF_SIRMDR1_SYNCDL_0		(0 << 20)
+#define RCAR_DRIF_SIRMDR1_SYNCDL_1		(1 << 20)
+#define RCAR_DRIF_SIRMDR1_SYNCDL_2		(2 << 20)
+#define RCAR_DRIF_SIRMDR1_SYNCDL_3		(3 << 20)
+#define RCAR_DRIF_SIRMDR1_SYNCDL_0PT5		(5 << 20)
+#define RCAR_DRIF_SIRMDR1_SYNCDL_1PT5		(6 << 20)
+
+#define RCAR_DRIF_MDR_GRPCNT(n)			(((n) - 1) << 30)
+#define RCAR_DRIF_MDR_BITLEN(n)			(((n) - 1) << 24)
+#define RCAR_DRIF_MDR_WDCNT(n)			(((n) - 1) << 16)
+
+/* Hidden Transmit register that controls CLK & SYNC */
+#define RCAR_DRIF_SITMDR1_PCON			BIT(30)
+
+#define RCAR_DRIF_SICTR_RX_RISING_EDGE		BIT(26)
+#define RCAR_DRIF_SICTR_RX_EN			BIT(8)
+#define RCAR_DRIF_SICTR_RESET			BIT(0)
+
+/* Constants */
+#define RCAR_DRIF_NUM_HWBUFS			32
+#define RCAR_DRIF_MAX_DEVS			4
+#define RCAR_DRIF_DEFAULT_NUM_HWBUFS		16
+#define RCAR_DRIF_DEFAULT_HWBUF_SIZE		(4 * PAGE_SIZE)
+#define RCAR_DRIF_MAX_CHANNEL			2
+#define RCAR_SDR_BUFFER_SIZE			SZ_64K
+
+/* Internal buffer status flags */
+#define RCAR_DRIF_BUF_DONE			BIT(0)	/* DMA completed */
+#define RCAR_DRIF_BUF_OVERFLOW			BIT(1)	/* Overflow detected */
+
+#define to_rcar_drif_buf_pair(sdr, ch_num, idx)			\
+	(&((sdr)->ch[!(ch_num)]->buf[(idx)]))
+
+#define for_each_rcar_drif_channel(ch, ch_mask)			\
+	for_each_set_bit(ch, ch_mask, RCAR_DRIF_MAX_CHANNEL)
+
+/* Debug */
+#define rdrif_dbg(sdr, fmt, arg...)				\
+	dev_dbg(sdr->v4l2_dev.dev, fmt, ## arg)
+
+#define rdrif_err(sdr, fmt, arg...)				\
+	dev_err(sdr->v4l2_dev.dev, fmt, ## arg)
+
+/* Stream formats */
+struct rcar_drif_format {
+	u32	pixelformat;
+	u32	buffersize;
+	u32	bitlen;
+	u32	wdcnt;
+	u32	num_ch;
+};
+
+/* Format descriptions for capture */
+static const struct rcar_drif_format formats[] = {
+	{
+		.pixelformat	= V4L2_SDR_FMT_PCU16BE,
+		.buffersize	= RCAR_SDR_BUFFER_SIZE,
+		.bitlen		= 16,
+		.wdcnt		= 1,
+		.num_ch		= 2,
+	},
+	{
+		.pixelformat	= V4L2_SDR_FMT_PCU18BE,
+		.buffersize	= RCAR_SDR_BUFFER_SIZE,
+		.bitlen		= 18,
+		.wdcnt		= 1,
+		.num_ch		= 2,
+	},
+	{
+		.pixelformat	= V4L2_SDR_FMT_PCU20BE,
+		.buffersize	= RCAR_SDR_BUFFER_SIZE,
+		.bitlen		= 20,
+		.wdcnt		= 1,
+		.num_ch		= 2,
+	},
+};
+
+/* Buffer for a received frame from one or both internal channels */
+struct rcar_drif_frame_buf {
+	/* Common v4l buffer stuff -- must be first */
+	struct vb2_v4l2_buffer vb;
+	struct list_head list;
+};
+
+/* OF graph endpoint's V4L2 async data */
+struct rcar_drif_graph_ep {
+	struct v4l2_subdev *subdev;	/* Async matched subdev */
+	struct v4l2_async_subdev asd;	/* Async sub-device descriptor */
+};
+
+/* DMA buffer */
+struct rcar_drif_hwbuf {
+	void *addr;			/* CPU-side address */
+	unsigned int status;		/* Buffer status flags */
+};
+
+/* Internal channel */
+struct rcar_drif {
+	struct rcar_drif_sdr *sdr;	/* Group device */
+	struct platform_device *pdev;	/* Channel's pdev */
+	void __iomem *base;		/* Base register address */
+	resource_size_t start;		/* I/O resource offset */
+	struct dma_chan *dmach;		/* Reserved DMA channel */
+	struct clk *clk;		/* Module clock */
+	struct rcar_drif_hwbuf buf[RCAR_DRIF_NUM_HWBUFS]; /* H/W bufs */
+	dma_addr_t dma_handle;		/* Handle for all bufs */
+	unsigned int num;		/* Channel number */
+	bool acting_sdr;		/* Channel acting as SDR device */
+};
+
+/* DRIF V4L2 SDR */
+struct rcar_drif_sdr {
+	struct device *dev;		/* Platform device */
+	struct video_device *vdev;	/* V4L2 SDR device */
+	struct v4l2_device v4l2_dev;	/* V4L2 device */
+
+	/* Videobuf2 queue and queued buffers list */
+	struct vb2_queue vb_queue;
+	struct list_head queued_bufs;
+	spinlock_t queued_bufs_lock;	/* Protects queued_bufs */
+	spinlock_t dma_lock;		/* To serialize DMA cb of channels */
+
+	struct mutex v4l2_mutex;	/* To serialize ioctls */
+	struct mutex vb_queue_mutex;	/* To serialize streaming ioctls */
+	struct v4l2_ctrl_handler ctrl_hdl;	/* SDR control handler */
+	struct v4l2_async_notifier notifier;	/* For subdev (tuner) */
+	struct rcar_drif_graph_ep ep;	/* Endpoint V4L2 async data */
+
+	/* Current V4L2 SDR format ptr */
+	const struct rcar_drif_format *fmt;
+
+	/* Device tree SYNC properties */
+	u32 mdr1;
+
+	/* Internals */
+	struct rcar_drif *ch[RCAR_DRIF_MAX_CHANNEL]; /* DRIFx0,1 */
+	unsigned long hw_ch_mask;	/* Enabled channels per DT */
+	unsigned long cur_ch_mask;	/* Used channels for an SDR FMT */
+	u32 num_hw_ch;			/* Num of DT enabled channels */
+	u32 num_cur_ch;			/* Num of used channels */
+	u32 hwbuf_size;			/* Each DMA buffer size */
+	u32 produced;			/* Buffers produced by sdr dev */
+};
+
+/* Register access functions */
+static void rcar_drif_write(struct rcar_drif *ch, u32 offset, u32 data)
+{
+	writel(data, ch->base + offset);
+}
+
+static u32 rcar_drif_read(struct rcar_drif *ch, u32 offset)
+{
+	return readl(ch->base + offset);
+}
+
+/* Release DMA channels */
+static void rcar_drif_release_dmachannels(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask)
+		if (sdr->ch[i]->dmach) {
+			dma_release_channel(sdr->ch[i]->dmach);
+			sdr->ch[i]->dmach = NULL;
+		}
+}
+
+/* Allocate DMA channels */
+static int rcar_drif_alloc_dmachannels(struct rcar_drif_sdr *sdr)
+{
+	struct dma_slave_config dma_cfg;
+	unsigned int i;
+	int ret = -ENODEV;
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		struct rcar_drif *ch = sdr->ch[i];
+
+		ch->dmach = dma_request_slave_channel(&ch->pdev->dev, "rx");
+		if (!ch->dmach) {
+			rdrif_err(sdr, "ch%u: dma channel req failed\n", i);
+			goto dmach_error;
+		}
+
+		/* Configure slave */
+		memset(&dma_cfg, 0, sizeof(dma_cfg));
+		dma_cfg.src_addr = (phys_addr_t)(ch->start + RCAR_DRIF_SIRFDR);
+		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+		ret = dmaengine_slave_config(ch->dmach, &dma_cfg);
+		if (ret) {
+			rdrif_err(sdr, "ch%u: dma slave config failed\n", i);
+			goto dmach_error;
+		}
+	}
+	return 0;
+
+dmach_error:
+	rcar_drif_release_dmachannels(sdr);
+	return ret;
+}
+
+/* Release queued vb2 buffers */
+static void rcar_drif_release_queued_bufs(struct rcar_drif_sdr *sdr,
+					  enum vb2_buffer_state state)
+{
+	struct rcar_drif_frame_buf *fbuf, *tmp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sdr->queued_bufs_lock, flags);
+	list_for_each_entry_safe(fbuf, tmp, &sdr->queued_bufs, list) {
+		list_del(&fbuf->list);
+		vb2_buffer_done(&fbuf->vb.vb2_buf, state);
+	}
+	spin_unlock_irqrestore(&sdr->queued_bufs_lock, flags);
+}
+
+/* Set MDR defaults */
+static inline void rcar_drif_set_mdr1(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+
+	/* Set defaults for enabled internal channels */
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		/* Refer MSIOF section in manual for this register setting */
+		rcar_drif_write(sdr->ch[i], RCAR_DRIF_SITMDR1,
+				RCAR_DRIF_SITMDR1_PCON);
+
+		/* Setup MDR1 value */
+		rcar_drif_write(sdr->ch[i], RCAR_DRIF_SIRMDR1, sdr->mdr1);
+
+		rdrif_dbg(sdr, "ch%u: mdr1 = 0x%08x",
+			  i, rcar_drif_read(sdr->ch[i], RCAR_DRIF_SIRMDR1));
+	}
+}
+
+/* Set DRIF receive format */
+static int rcar_drif_set_format(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+
+	rdrif_dbg(sdr, "setfmt: bitlen %u wdcnt %u num_ch %u\n",
+		  sdr->fmt->bitlen, sdr->fmt->wdcnt, sdr->fmt->num_ch);
+
+	/* Sanity check */
+	if (sdr->fmt->num_ch > sdr->num_cur_ch) {
+		rdrif_err(sdr, "fmt num_ch %u cur_ch %u mismatch\n",
+			  sdr->fmt->num_ch, sdr->num_cur_ch);
+		return -EINVAL;
+	}
+
+	/* Setup group, bitlen & wdcnt */
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		u32 mdr;
+
+		/* Two groups */
+		mdr = RCAR_DRIF_MDR_GRPCNT(2) |
+			RCAR_DRIF_MDR_BITLEN(sdr->fmt->bitlen) |
+			RCAR_DRIF_MDR_WDCNT(sdr->fmt->wdcnt);
+		rcar_drif_write(sdr->ch[i], RCAR_DRIF_SIRMDR2, mdr);
+
+		mdr = RCAR_DRIF_MDR_BITLEN(sdr->fmt->bitlen) |
+			RCAR_DRIF_MDR_WDCNT(sdr->fmt->wdcnt);
+		rcar_drif_write(sdr->ch[i], RCAR_DRIF_SIRMDR3, mdr);
+
+		rdrif_dbg(sdr, "ch%u: new mdr[2,3] = 0x%08x, 0x%08x\n",
+			  i, rcar_drif_read(sdr->ch[i], RCAR_DRIF_SIRMDR2),
+			  rcar_drif_read(sdr->ch[i], RCAR_DRIF_SIRMDR3));
+	}
+	return 0;
+}
+
+/* Release DMA buffers */
+static void rcar_drif_release_buf(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		struct rcar_drif *ch = sdr->ch[i];
+
+		/* First entry contains the dma buf ptr */
+		if (ch->buf[0].addr) {
+			dma_free_coherent(&ch->pdev->dev,
+				sdr->hwbuf_size * RCAR_DRIF_NUM_HWBUFS,
+				ch->buf[0].addr, ch->dma_handle);
+			ch->buf[0].addr = NULL;
+		}
+	}
+}
+
+/* Request DMA buffers */
+static int rcar_drif_request_buf(struct rcar_drif_sdr *sdr)
+{
+	int ret = -ENOMEM;
+	unsigned int i, j;
+	void *addr;
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		struct rcar_drif *ch = sdr->ch[i];
+
+		/* Allocate DMA buffers */
+		addr = dma_alloc_coherent(&ch->pdev->dev,
+				sdr->hwbuf_size * RCAR_DRIF_NUM_HWBUFS,
+				&ch->dma_handle, GFP_KERNEL);
+		if (!addr) {
+			rdrif_err(sdr,
+			"ch%u: dma alloc failed. num hwbufs %u size %u\n",
+			i, RCAR_DRIF_NUM_HWBUFS, sdr->hwbuf_size);
+			goto error;
+		}
+
+		/* Split the chunk and populate bufctxt */
+		for (j = 0; j < RCAR_DRIF_NUM_HWBUFS; j++) {
+			ch->buf[j].addr = addr + (j * sdr->hwbuf_size);
+			ch->buf[j].status = 0;
+		}
+	}
+	return 0;
+error:
+	return ret;
+}
+
+/* Setup vb_queue minimum buffer requirements */
+static int rcar_drif_queue_setup(struct vb2_queue *vq,
+			unsigned int *num_buffers, unsigned int *num_planes,
+			unsigned int sizes[], struct device *alloc_devs[])
+{
+	struct rcar_drif_sdr *sdr = vb2_get_drv_priv(vq);
+
+	/* Need at least 16 buffers */
+	if (vq->num_buffers + *num_buffers < 16)
+		*num_buffers = 16 - vq->num_buffers;
+
+	*num_planes = 1;
+	sizes[0] = PAGE_ALIGN(sdr->fmt->buffersize);
+	rdrif_dbg(sdr, "num_bufs %d sizes[0] %d\n", *num_buffers, sizes[0]);
+
+	return 0;
+}
+
+/* Enqueue buffer */
+static void rcar_drif_buf_queue(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct rcar_drif_sdr *sdr = vb2_get_drv_priv(vb->vb2_queue);
+	struct rcar_drif_frame_buf *fbuf =
+			container_of(vbuf, struct rcar_drif_frame_buf, vb);
+	unsigned long flags;
+
+	rdrif_dbg(sdr, "buf_queue idx %u\n", vb->index);
+	spin_lock_irqsave(&sdr->queued_bufs_lock, flags);
+	list_add_tail(&fbuf->list, &sdr->queued_bufs);
+	spin_unlock_irqrestore(&sdr->queued_bufs_lock, flags);
+}
+
+/* Get a frame buf from list */
+static struct rcar_drif_frame_buf *
+rcar_drif_get_fbuf(struct rcar_drif_sdr *sdr)
+{
+	struct rcar_drif_frame_buf *fbuf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&sdr->queued_bufs_lock, flags);
+	fbuf = list_first_entry_or_null(&sdr->queued_bufs, struct
+					rcar_drif_frame_buf, list);
+	if (!fbuf) {
+		/*
+		 * App is late in enqueing buffers. Samples lost & there will
+		 * be a gap in sequence number when app recovers
+		 */
+		rdrif_dbg(sdr, "\napp late: prod %u\n", sdr->produced);
+		spin_unlock_irqrestore(&sdr->queued_bufs_lock, flags);
+		return NULL;
+	}
+	list_del(&fbuf->list);
+	spin_unlock_irqrestore(&sdr->queued_bufs_lock, flags);
+
+	return fbuf;
+}
+
+/* Helpers to set/clear buf pair status */
+static inline bool rcar_drif_bufs_done(struct rcar_drif_hwbuf **buf)
+{
+	return (buf[0]->status & buf[1]->status & RCAR_DRIF_BUF_DONE);
+}
+
+static inline bool rcar_drif_bufs_overflow(struct rcar_drif_hwbuf **buf)
+{
+	return ((buf[0]->status | buf[1]->status) & RCAR_DRIF_BUF_OVERFLOW);
+}
+
+static inline void rcar_drif_bufs_clear(struct rcar_drif_hwbuf **buf,
+					unsigned int bit)
+{
+	unsigned int i;
+
+	for (i = 0; i < RCAR_DRIF_MAX_CHANNEL; i++)
+		buf[i]->status &= ~bit;
+}
+
+/* Channel DMA complete */
+static void rcar_drif_channel_complete(struct rcar_drif *ch, u32 idx)
+{
+	u32 str;
+
+	ch->buf[idx].status |= RCAR_DRIF_BUF_DONE;
+
+	/* Check for DRIF errors */
+	str = rcar_drif_read(ch, RCAR_DRIF_SISTR);
+	if (unlikely(str & RCAR_DRIF_RFOVF)) {
+		/* Writing the same clears it */
+		rcar_drif_write(ch, RCAR_DRIF_SISTR, str);
+
+		/* Overflow: some samples are lost */
+		ch->buf[idx].status |= RCAR_DRIF_BUF_OVERFLOW;
+	}
+}
+
+/* DMA callback for each stage */
+static void rcar_drif_dma_complete(void *dma_async_param)
+{
+	struct rcar_drif *ch = dma_async_param;
+	struct rcar_drif_sdr *sdr = ch->sdr;
+	struct rcar_drif_hwbuf *buf[RCAR_DRIF_MAX_CHANNEL];
+	struct rcar_drif_frame_buf *fbuf;
+	bool overflow = false;
+	u32 idx, produced;
+	unsigned int i;
+
+	spin_lock(&sdr->dma_lock);
+
+	/* DMA can be terminated while the callback was waiting on lock */
+	if (!vb2_is_streaming(&sdr->vb_queue)) {
+		spin_unlock(&sdr->dma_lock);
+		return;
+	}
+
+	idx = sdr->produced % RCAR_DRIF_NUM_HWBUFS;
+	rcar_drif_channel_complete(ch, idx);
+
+	if (sdr->num_cur_ch == RCAR_DRIF_MAX_CHANNEL) {
+		buf[0] = ch->num ? to_rcar_drif_buf_pair(sdr, ch->num, idx) :
+				&ch->buf[idx];
+		buf[1] = ch->num ? &ch->buf[idx] :
+				to_rcar_drif_buf_pair(sdr, ch->num, idx);
+
+		/* Check if both DMA buffers are done */
+		if (!rcar_drif_bufs_done(buf)) {
+			spin_unlock(&sdr->dma_lock);
+			return;
+		}
+
+		/* Clear buf done status */
+		rcar_drif_bufs_clear(buf, RCAR_DRIF_BUF_DONE);
+
+		if (rcar_drif_bufs_overflow(buf)) {
+			overflow = true;
+			/* Clear the flag in status */
+			rcar_drif_bufs_clear(buf, RCAR_DRIF_BUF_OVERFLOW);
+		}
+	} else {
+		buf[0] = &ch->buf[idx];
+		if (buf[0]->status & RCAR_DRIF_BUF_OVERFLOW) {
+			overflow = true;
+			/* Clear the flag in status */
+			buf[0]->status &= ~RCAR_DRIF_BUF_OVERFLOW;
+		}
+	}
+
+	/* Buffer produced for consumption */
+	produced = sdr->produced++;
+	spin_unlock(&sdr->dma_lock);
+
+	rdrif_dbg(sdr, "ch%u: prod %u\n", ch->num, produced);
+
+	/* Get fbuf */
+	fbuf = rcar_drif_get_fbuf(sdr);
+	if (!fbuf)
+		return;
+
+	for (i = 0; i < RCAR_DRIF_MAX_CHANNEL; i++)
+		memcpy(vb2_plane_vaddr(&fbuf->vb.vb2_buf, 0) +
+		       i * sdr->hwbuf_size, buf[i]->addr, sdr->hwbuf_size);
+
+	fbuf->vb.field = V4L2_FIELD_NONE;
+	fbuf->vb.sequence = produced;
+	fbuf->vb.vb2_buf.timestamp = ktime_get_ns();
+	vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0, sdr->fmt->buffersize);
+
+	/* Set error state on overflow */
+	vb2_buffer_done(&fbuf->vb.vb2_buf,
+			overflow ? VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
+}
+
+static int rcar_drif_qbuf(struct rcar_drif *ch)
+{
+	struct rcar_drif_sdr *sdr = ch->sdr;
+	dma_addr_t addr = ch->dma_handle;
+	struct dma_async_tx_descriptor *rxd;
+	dma_cookie_t cookie;
+	int ret = -EIO;
+
+	/* Setup cyclic DMA with given buffers */
+	rxd = dmaengine_prep_dma_cyclic(ch->dmach, addr,
+					sdr->hwbuf_size * RCAR_DRIF_NUM_HWBUFS,
+					sdr->hwbuf_size, DMA_DEV_TO_MEM,
+					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+	if (!rxd) {
+		rdrif_err(sdr, "ch%u: prep dma cyclic failed\n", ch->num);
+		return ret;
+	}
+
+	/* Submit descriptor */
+	rxd->callback = rcar_drif_dma_complete;
+	rxd->callback_param = ch;
+	cookie = dmaengine_submit(rxd);
+	if (dma_submit_error(cookie)) {
+		rdrif_err(sdr, "ch%u: dma submit failed\n", ch->num);
+		return ret;
+	}
+
+	dma_async_issue_pending(ch->dmach);
+	return 0;
+}
+
+/* Enable reception */
+static int rcar_drif_enable_rx(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+	u32 ctr;
+	int ret;
+
+	/*
+	 * When both internal channels are enabled, they can be synchronized
+	 * only by the master
+	 */
+
+	/* Enable receive */
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		ctr = rcar_drif_read(sdr->ch[i], RCAR_DRIF_SICTR);
+		ctr |= (RCAR_DRIF_SICTR_RX_RISING_EDGE |
+			 RCAR_DRIF_SICTR_RX_EN);
+		rcar_drif_write(sdr->ch[i], RCAR_DRIF_SICTR, ctr);
+	}
+
+	/* Check receive enabled */
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		ret = readl_poll_timeout(sdr->ch[i]->base + RCAR_DRIF_SICTR,
+				ctr, ctr & RCAR_DRIF_SICTR_RX_EN, 7, 100000);
+		if (ret) {
+			rdrif_err(sdr, "ch%u: rx en failed. ctr 0x%08x\n", i,
+				  rcar_drif_read(sdr->ch[i], RCAR_DRIF_SICTR));
+			break;
+		}
+	}
+	return ret;
+}
+
+/* Disable reception */
+static void rcar_drif_disable_rx(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+	u32 ctr;
+	int ret;
+
+	/* Disable receive */
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		ctr = rcar_drif_read(sdr->ch[i], RCAR_DRIF_SICTR);
+		ctr &= ~RCAR_DRIF_SICTR_RX_EN;
+		rcar_drif_write(sdr->ch[i], RCAR_DRIF_SICTR, ctr);
+	}
+
+	/* Check receive disabled */
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		ret = readl_poll_timeout(sdr->ch[i]->base + RCAR_DRIF_SICTR,
+				ctr, !(ctr & RCAR_DRIF_SICTR_RX_EN), 7, 100000);
+		if (ret)
+			dev_warn(&sdr->vdev->dev,
+			"ch%u: failed to disable rx. ctr 0x%08x\n",
+			i, rcar_drif_read(sdr->ch[i], RCAR_DRIF_SICTR));
+	}
+}
+
+/* Stop channel */
+static void rcar_drif_stop_channel(struct rcar_drif *ch)
+{
+	/* Disable DMA receive interrupt */
+	rcar_drif_write(ch, RCAR_DRIF_SIIER, 0x00000000);
+
+	/* Terminate all DMA transfers */
+	dmaengine_terminate_sync(ch->dmach);
+}
+
+/* Stop receive operation */
+static void rcar_drif_stop(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+
+	/* Disable Rx */
+	rcar_drif_disable_rx(sdr);
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask)
+		rcar_drif_stop_channel(sdr->ch[i]);
+}
+
+/* Start channel */
+static int rcar_drif_start_channel(struct rcar_drif *ch)
+{
+	struct rcar_drif_sdr *sdr = ch->sdr;
+	u32 ctr, str;
+	int ret;
+
+	/* Reset receive */
+	rcar_drif_write(ch, RCAR_DRIF_SICTR, RCAR_DRIF_SICTR_RESET);
+	ret = readl_poll_timeout(ch->base + RCAR_DRIF_SICTR, ctr,
+				 !(ctr & RCAR_DRIF_SICTR_RESET), 7, 100000);
+	if (ret) {
+		rdrif_err(sdr, "ch%u: failed to reset rx. ctr 0x%08x\n",
+			  ch->num, rcar_drif_read(ch, RCAR_DRIF_SICTR));
+		return ret;
+	}
+
+	/* Queue buffers for DMA */
+	ret = rcar_drif_qbuf(ch);
+	if (ret)
+		return ret;
+
+	/* Clear status register flags */
+	str = RCAR_DRIF_RFFUL | RCAR_DRIF_REOF | RCAR_DRIF_RFSERR |
+		RCAR_DRIF_RFUDF | RCAR_DRIF_RFOVF;
+	rcar_drif_write(ch, RCAR_DRIF_SISTR, str);
+
+	/* Enable DMA receive interrupt */
+	rcar_drif_write(ch, RCAR_DRIF_SIIER, 0x00009000);
+
+	return ret;
+}
+
+/* Start receive operation */
+static int rcar_drif_start(struct rcar_drif_sdr *sdr)
+{
+	unsigned long enabled = 0;
+	unsigned int i;
+	int ret;
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		ret = rcar_drif_start_channel(sdr->ch[i]);
+		if (ret)
+			goto start_error;
+		enabled |= BIT(i);
+	}
+
+	ret = rcar_drif_enable_rx(sdr);
+	if (ret)
+		goto enable_error;
+
+	sdr->produced = 0;
+	return ret;
+
+enable_error:
+	rcar_drif_disable_rx(sdr);
+start_error:
+	for_each_rcar_drif_channel(i, &enabled)
+		rcar_drif_stop_channel(sdr->ch[i]);
+
+	return ret;
+}
+
+/* Start streaming */
+static int rcar_drif_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct rcar_drif_sdr *sdr = vb2_get_drv_priv(vq);
+	unsigned long enabled = 0;
+	unsigned int i;
+	int ret;
+
+	mutex_lock(&sdr->v4l2_mutex);
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask) {
+		ret = clk_prepare_enable(sdr->ch[i]->clk);
+		if (ret)
+			goto error;
+		enabled |= BIT(i);
+	}
+
+	/* Set default MDRx settings */
+	rcar_drif_set_mdr1(sdr);
+
+	/* Set new format */
+	ret = rcar_drif_set_format(sdr);
+	if (ret)
+		goto error;
+
+	if (sdr->num_cur_ch == RCAR_DRIF_MAX_CHANNEL)
+		sdr->hwbuf_size = sdr->fmt->buffersize / RCAR_DRIF_MAX_CHANNEL;
+	else
+		sdr->hwbuf_size = sdr->fmt->buffersize;
+
+	rdrif_dbg(sdr, "num hwbufs %u, hwbuf_size %u\n",
+		RCAR_DRIF_NUM_HWBUFS, sdr->hwbuf_size);
+
+	/* Alloc DMA channel */
+	ret = rcar_drif_alloc_dmachannels(sdr);
+	if (ret)
+		goto error;
+
+	/* Request buffers */
+	ret = rcar_drif_request_buf(sdr);
+	if (ret)
+		goto error;
+
+	/* Start Rx */
+	ret = rcar_drif_start(sdr);
+	if (ret)
+		goto error;
+
+	mutex_unlock(&sdr->v4l2_mutex);
+
+	return ret;
+
+error:
+	rcar_drif_release_queued_bufs(sdr, VB2_BUF_STATE_QUEUED);
+	rcar_drif_release_buf(sdr);
+	rcar_drif_release_dmachannels(sdr);
+	for_each_rcar_drif_channel(i, &enabled)
+		clk_disable_unprepare(sdr->ch[i]->clk);
+
+	mutex_unlock(&sdr->v4l2_mutex);
+
+	return ret;
+}
+
+/* Stop streaming */
+static void rcar_drif_stop_streaming(struct vb2_queue *vq)
+{
+	struct rcar_drif_sdr *sdr = vb2_get_drv_priv(vq);
+	unsigned int i;
+
+	mutex_lock(&sdr->v4l2_mutex);
+
+	/* Stop hardware streaming */
+	rcar_drif_stop(sdr);
+
+	/* Return all queued buffers to vb2 */
+	rcar_drif_release_queued_bufs(sdr, VB2_BUF_STATE_ERROR);
+
+	/* Release buf */
+	rcar_drif_release_buf(sdr);
+
+	/* Release DMA channel resources */
+	rcar_drif_release_dmachannels(sdr);
+
+	for_each_rcar_drif_channel(i, &sdr->cur_ch_mask)
+		clk_disable_unprepare(sdr->ch[i]->clk);
+
+	mutex_unlock(&sdr->v4l2_mutex);
+}
+
+/* Vb2 ops */
+static const struct vb2_ops rcar_drif_vb2_ops = {
+	.queue_setup            = rcar_drif_queue_setup,
+	.buf_queue              = rcar_drif_buf_queue,
+	.start_streaming        = rcar_drif_start_streaming,
+	.stop_streaming         = rcar_drif_stop_streaming,
+	.wait_prepare		= vb2_ops_wait_prepare,
+	.wait_finish		= vb2_ops_wait_finish,
+};
+
+static int rcar_drif_querycap(struct file *file, void *fh,
+			      struct v4l2_capability *cap)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
+	strlcpy(cap->card, sdr->vdev->name, sizeof(cap->card));
+	snprintf(cap->bus_info, sizeof(cap->bus_info), "platform:%s",
+		 sdr->vdev->name);
+
+	return 0;
+}
+
+static int rcar_drif_set_default_format(struct rcar_drif_sdr *sdr)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(formats); i++) {
+		/* Matching fmt based on required channels is set as default */
+		if (sdr->num_hw_ch == formats[i].num_ch) {
+			sdr->fmt = &formats[i];
+			sdr->cur_ch_mask = sdr->hw_ch_mask;
+			sdr->num_cur_ch = sdr->num_hw_ch;
+			dev_dbg(sdr->dev, "default fmt[%u]: mask %lu num %u\n",
+				i, sdr->cur_ch_mask, sdr->num_cur_ch);
+			return 0;
+		}
+	}
+	return -EINVAL;
+}
+
+static int rcar_drif_enum_fmt_sdr_cap(struct file *file, void *priv,
+				      struct v4l2_fmtdesc *f)
+{
+	if (f->index >= ARRAY_SIZE(formats))
+		return -EINVAL;
+
+	f->pixelformat = formats[f->index].pixelformat;
+
+	return 0;
+}
+
+static int rcar_drif_g_fmt_sdr_cap(struct file *file, void *priv,
+				   struct v4l2_format *f)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	f->fmt.sdr.pixelformat = sdr->fmt->pixelformat;
+	f->fmt.sdr.buffersize = sdr->fmt->buffersize;
+
+	return 0;
+}
+
+static int rcar_drif_s_fmt_sdr_cap(struct file *file, void *priv,
+				   struct v4l2_format *f)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+	struct vb2_queue *q = &sdr->vb_queue;
+	unsigned int i;
+
+	if (vb2_is_busy(q))
+		return -EBUSY;
+
+	for (i = 0; i < ARRAY_SIZE(formats); i++) {
+		if (formats[i].pixelformat == f->fmt.sdr.pixelformat)
+			break;
+	}
+
+	if (i == ARRAY_SIZE(formats))
+		i = 0;		/* Set the 1st format as default on no match */
+
+	sdr->fmt = &formats[i];
+	f->fmt.sdr.pixelformat = sdr->fmt->pixelformat;
+	f->fmt.sdr.buffersize = formats[i].buffersize;
+	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
+
+	/*
+	 * If a format demands one channel only out of two
+	 * enabled channels, pick the 0th channel.
+	 */
+	if (formats[i].num_ch < sdr->num_hw_ch) {
+		sdr->cur_ch_mask = BIT(0);
+		sdr->num_cur_ch = formats[i].num_ch;
+	} else {
+		sdr->cur_ch_mask = sdr->hw_ch_mask;
+		sdr->num_cur_ch = sdr->num_hw_ch;
+	}
+
+	rdrif_dbg(sdr, "cur: idx %u mask %lu num %u\n",
+		  i, sdr->cur_ch_mask, sdr->num_cur_ch);
+
+	return 0;
+}
+
+static int rcar_drif_try_fmt_sdr_cap(struct file *file, void *priv,
+				     struct v4l2_format *f)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(formats); i++) {
+		if (formats[i].pixelformat == f->fmt.sdr.pixelformat) {
+			f->fmt.sdr.buffersize = formats[i].buffersize;
+			return 0;
+		}
+	}
+
+	f->fmt.sdr.pixelformat = formats[0].pixelformat;
+	f->fmt.sdr.buffersize = formats[0].buffersize;
+	memset(f->fmt.sdr.reserved, 0, sizeof(f->fmt.sdr.reserved));
+
+	return 0;
+}
+
+/* Tuner subdev ioctls */
+static int rcar_drif_enum_freq_bands(struct file *file, void *priv,
+				     struct v4l2_frequency_band *band)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	return v4l2_subdev_call(sdr->ep.subdev, tuner, enum_freq_bands, band);
+}
+
+static int rcar_drif_g_frequency(struct file *file, void *priv,
+				 struct v4l2_frequency *f)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	return v4l2_subdev_call(sdr->ep.subdev, tuner, g_frequency, f);
+}
+
+static int rcar_drif_s_frequency(struct file *file, void *priv,
+				 const struct v4l2_frequency *f)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	return v4l2_subdev_call(sdr->ep.subdev, tuner, s_frequency, f);
+}
+
+static int rcar_drif_g_tuner(struct file *file, void *priv,
+			     struct v4l2_tuner *vt)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	return v4l2_subdev_call(sdr->ep.subdev, tuner, g_tuner, vt);
+}
+
+static int rcar_drif_s_tuner(struct file *file, void *priv,
+			     const struct v4l2_tuner *vt)
+{
+	struct rcar_drif_sdr *sdr = video_drvdata(file);
+
+	return v4l2_subdev_call(sdr->ep.subdev, tuner, s_tuner, vt);
+}
+
+static const struct v4l2_ioctl_ops rcar_drif_ioctl_ops = {
+	.vidioc_querycap          = rcar_drif_querycap,
+
+	.vidioc_enum_fmt_sdr_cap  = rcar_drif_enum_fmt_sdr_cap,
+	.vidioc_g_fmt_sdr_cap     = rcar_drif_g_fmt_sdr_cap,
+	.vidioc_s_fmt_sdr_cap     = rcar_drif_s_fmt_sdr_cap,
+	.vidioc_try_fmt_sdr_cap   = rcar_drif_try_fmt_sdr_cap,
+
+	.vidioc_reqbufs           = vb2_ioctl_reqbufs,
+	.vidioc_create_bufs       = vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf       = vb2_ioctl_prepare_buf,
+	.vidioc_querybuf          = vb2_ioctl_querybuf,
+	.vidioc_qbuf              = vb2_ioctl_qbuf,
+	.vidioc_dqbuf             = vb2_ioctl_dqbuf,
+
+	.vidioc_streamon          = vb2_ioctl_streamon,
+	.vidioc_streamoff         = vb2_ioctl_streamoff,
+
+	.vidioc_s_frequency       = rcar_drif_s_frequency,
+	.vidioc_g_frequency       = rcar_drif_g_frequency,
+	.vidioc_s_tuner		  = rcar_drif_s_tuner,
+	.vidioc_g_tuner		  = rcar_drif_g_tuner,
+	.vidioc_enum_freq_bands   = rcar_drif_enum_freq_bands,
+	.vidioc_subscribe_event   = v4l2_ctrl_subscribe_event,
+	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+	.vidioc_log_status        = v4l2_ctrl_log_status,
+};
+
+static const struct v4l2_file_operations rcar_drif_fops = {
+	.owner                    = THIS_MODULE,
+	.open                     = v4l2_fh_open,
+	.release                  = vb2_fop_release,
+	.read                     = vb2_fop_read,
+	.poll                     = vb2_fop_poll,
+	.mmap                     = vb2_fop_mmap,
+	.unlocked_ioctl           = video_ioctl2,
+};
+
+static int rcar_drif_sdr_register(struct rcar_drif_sdr *sdr)
+{
+	int ret;
+
+	/* Init video_device structure */
+	sdr->vdev = video_device_alloc();
+	if (!sdr->vdev)
+		return -ENOMEM;
+
+	snprintf(sdr->vdev->name, sizeof(sdr->vdev->name), "R-Car DRIF");
+	sdr->vdev->fops = &rcar_drif_fops;
+	sdr->vdev->ioctl_ops = &rcar_drif_ioctl_ops;
+	sdr->vdev->release = video_device_release;
+	sdr->vdev->lock = &sdr->v4l2_mutex;
+	sdr->vdev->queue = &sdr->vb_queue;
+	sdr->vdev->queue->lock = &sdr->vb_queue_mutex;
+	sdr->vdev->ctrl_handler = &sdr->ctrl_hdl;
+	sdr->vdev->v4l2_dev = &sdr->v4l2_dev;
+	sdr->vdev->device_caps = V4L2_CAP_SDR_CAPTURE | V4L2_CAP_TUNER |
+		V4L2_CAP_STREAMING | V4L2_CAP_READWRITE;
+	video_set_drvdata(sdr->vdev, sdr);
+
+	/* Register V4L2 SDR device */
+	ret = video_register_device(sdr->vdev, VFL_TYPE_SDR, -1);
+	if (ret) {
+		video_device_release(sdr->vdev);
+		sdr->vdev = NULL;
+		dev_err(sdr->dev, "failed video_register_device (%d)\n", ret);
+	}
+
+	return ret;
+}
+
+static void rcar_drif_sdr_unregister(struct rcar_drif_sdr *sdr)
+{
+	video_unregister_device(sdr->vdev);
+	sdr->vdev = NULL;
+}
+
+/* Sub-device bound callback */
+static int rcar_drif_notify_bound(struct v4l2_async_notifier *notifier,
+				   struct v4l2_subdev *subdev,
+				   struct v4l2_async_subdev *asd)
+{
+	struct rcar_drif_sdr *sdr =
+		container_of(notifier, struct rcar_drif_sdr, notifier);
+
+	if (sdr->ep.asd.match.fwnode.fwnode !=
+	    of_fwnode_handle(subdev->dev->of_node)) {
+		rdrif_err(sdr, "subdev %s cannot bind\n", subdev->name);
+		return -EINVAL;
+	}
+
+	v4l2_set_subdev_hostdata(subdev, sdr);
+	sdr->ep.subdev = subdev;
+	rdrif_dbg(sdr, "bound asd %s\n", subdev->name);
+
+	return 0;
+}
+
+/* Sub-device unbind callback */
+static void rcar_drif_notify_unbind(struct v4l2_async_notifier *notifier,
+				   struct v4l2_subdev *subdev,
+				   struct v4l2_async_subdev *asd)
+{
+	struct rcar_drif_sdr *sdr =
+		container_of(notifier, struct rcar_drif_sdr, notifier);
+
+	if (sdr->ep.subdev != subdev) {
+		rdrif_err(sdr, "subdev %s is not bound\n", subdev->name);
+		return;
+	}
+
+	/* Free ctrl handler if initialized */
+	v4l2_ctrl_handler_free(&sdr->ctrl_hdl);
+	sdr->v4l2_dev.ctrl_handler = NULL;
+	sdr->ep.subdev = NULL;
+
+	rcar_drif_sdr_unregister(sdr);
+	rdrif_dbg(sdr, "unbind asd %s\n", subdev->name);
+}
+
+/* Sub-device registered notification callback */
+static int rcar_drif_notify_complete(struct v4l2_async_notifier *notifier)
+{
+	struct rcar_drif_sdr *sdr =
+		container_of(notifier, struct rcar_drif_sdr, notifier);
+	int ret;
+
+	/*
+	 * The subdev tested at this point uses 4 controls. Using 10 as a worst
+	 * case scenario hint. When less controls are needed there will be some
+	 * unused memory and when more controls are needed the framework uses
+	 * hash to manage controls within this number.
+	 */
+	ret = v4l2_ctrl_handler_init(&sdr->ctrl_hdl, 10);
+	if (ret)
+		return -ENOMEM;
+
+	sdr->v4l2_dev.ctrl_handler = &sdr->ctrl_hdl;
+	ret = v4l2_device_register_subdev_nodes(&sdr->v4l2_dev);
+	if (ret) {
+		rdrif_err(sdr, "failed: register subdev nodes ret %d\n", ret);
+		goto error;
+	}
+
+	ret = v4l2_ctrl_add_handler(&sdr->ctrl_hdl,
+				    sdr->ep.subdev->ctrl_handler, NULL);
+	if (ret) {
+		rdrif_err(sdr, "failed: ctrl add hdlr ret %d\n", ret);
+		goto error;
+	}
+
+	ret = rcar_drif_sdr_register(sdr);
+	if (ret)
+		goto error;
+
+	return ret;
+
+error:
+	v4l2_ctrl_handler_free(&sdr->ctrl_hdl);
+
+	return ret;
+}
+
+/* Read endpoint properties */
+static void rcar_drif_get_ep_properties(struct rcar_drif_sdr *sdr,
+					struct fwnode_handle *fwnode)
+{
+	u32 val;
+
+	/* Set the I2S defaults for SIRMDR1*/
+	sdr->mdr1 = RCAR_DRIF_SIRMDR1_SYNCMD_LR | RCAR_DRIF_SIRMDR1_MSB_FIRST |
+		RCAR_DRIF_SIRMDR1_DTDL_1 | RCAR_DRIF_SIRMDR1_SYNCDL_0;
+
+	/* Parse sync polarity from endpoint */
+	if (!fwnode_property_read_u32(fwnode, "sync-active", &val))
+		sdr->mdr1 |= val ? RCAR_DRIF_SIRMDR1_SYNCAC_POL_HIGH :
+			RCAR_DRIF_SIRMDR1_SYNCAC_POL_LOW;
+	else
+		sdr->mdr1 |= RCAR_DRIF_SIRMDR1_SYNCAC_POL_HIGH; /* default */
+
+	dev_dbg(sdr->dev, "mdr1 0x%08x\n", sdr->mdr1);
+}
+
+/* Parse sub-devs (tuner) to find a matching device */
+static int rcar_drif_parse_subdevs(struct rcar_drif_sdr *sdr)
+{
+	struct v4l2_async_notifier *notifier = &sdr->notifier;
+	struct fwnode_handle *fwnode, *ep;
+
+	notifier->subdevs = devm_kzalloc(sdr->dev, sizeof(*notifier->subdevs),
+					 GFP_KERNEL);
+	if (!notifier->subdevs)
+		return -ENOMEM;
+
+	ep = fwnode_graph_get_next_endpoint(of_fwnode_handle(sdr->dev->of_node),
+					    NULL);
+	if (!ep)
+		return 0;
+
+	notifier->subdevs[notifier->num_subdevs] = &sdr->ep.asd;
+	fwnode = fwnode_graph_get_remote_port_parent(ep);
+	if (!fwnode) {
+		dev_warn(sdr->dev, "bad remote port parent\n");
+		fwnode_handle_put(ep);
+		return -EINVAL;
+	}
+
+	sdr->ep.asd.match.fwnode.fwnode = fwnode;
+	sdr->ep.asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
+	notifier->num_subdevs++;
+
+	/* Get the endpoint properties */
+	rcar_drif_get_ep_properties(sdr, ep);
+
+	fwnode_handle_put(fwnode);
+	fwnode_handle_put(ep);
+
+	return 0;
+}
+
+/* Check if the given device is the primary bond */
+static bool rcar_drif_primary_bond(struct platform_device *pdev)
+{
+	return of_property_read_bool(pdev->dev.of_node, "renesas,primary-bond");
+}
+
+/* Check if both devices of the bond are enabled */
+static struct device_node *rcar_drif_bond_enabled(struct platform_device *p)
+{
+	struct device_node *np;
+
+	np = of_parse_phandle(p->dev.of_node, "renesas,bonding", 0);
+	if (np && of_device_is_available(np))
+		return np;
+
+	return NULL;
+}
+
+/* Check if the bonded device is probed */
+static int rcar_drif_bond_available(struct rcar_drif_sdr *sdr,
+				    struct device_node *np)
+{
+	struct platform_device *pdev;
+	struct rcar_drif *ch;
+	int ret = 0;
+
+	pdev = of_find_device_by_node(np);
+	if (!pdev) {
+		dev_err(sdr->dev, "failed to get bonded device from node\n");
+		return -ENODEV;
+	}
+
+	device_lock(&pdev->dev);
+	ch = platform_get_drvdata(pdev);
+	if (ch) {
+		/* Update sdr data in the bonded device */
+		ch->sdr = sdr;
+
+		/* Update sdr with bonded device data */
+		sdr->ch[ch->num] = ch;
+		sdr->hw_ch_mask |= BIT(ch->num);
+	} else {
+		/* Defer */
+		dev_info(sdr->dev, "defer probe\n");
+		ret = -EPROBE_DEFER;
+	}
+	device_unlock(&pdev->dev);
+
+	put_device(&pdev->dev);
+
+	return ret;
+}
+
+/* V4L2 SDR device probe */
+static int rcar_drif_sdr_probe(struct rcar_drif_sdr *sdr)
+{
+	int ret;
+
+	/* Validate any supported format for enabled channels */
+	ret = rcar_drif_set_default_format(sdr);
+	if (ret) {
+		dev_err(sdr->dev, "failed to set default format\n");
+		return ret;
+	}
+
+	/* Set defaults */
+	sdr->hwbuf_size = RCAR_DRIF_DEFAULT_HWBUF_SIZE;
+
+	mutex_init(&sdr->v4l2_mutex);
+	mutex_init(&sdr->vb_queue_mutex);
+	spin_lock_init(&sdr->queued_bufs_lock);
+	spin_lock_init(&sdr->dma_lock);
+	INIT_LIST_HEAD(&sdr->queued_bufs);
+
+	/* Init videobuf2 queue structure */
+	sdr->vb_queue.type = V4L2_BUF_TYPE_SDR_CAPTURE;
+	sdr->vb_queue.io_modes = VB2_READ | VB2_MMAP | VB2_DMABUF;
+	sdr->vb_queue.drv_priv = sdr;
+	sdr->vb_queue.buf_struct_size = sizeof(struct rcar_drif_frame_buf);
+	sdr->vb_queue.ops = &rcar_drif_vb2_ops;
+	sdr->vb_queue.mem_ops = &vb2_vmalloc_memops;
+	sdr->vb_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+
+	/* Init videobuf2 queue */
+	ret = vb2_queue_init(&sdr->vb_queue);
+	if (ret) {
+		dev_err(sdr->dev, "failed: vb2_queue_init ret %d\n", ret);
+		return ret;
+	}
+
+	/* Register the v4l2_device */
+	ret = v4l2_device_register(sdr->dev, &sdr->v4l2_dev);
+	if (ret) {
+		dev_err(sdr->dev, "failed: v4l2_device_register ret %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * Parse subdevs after v4l2_device_register because if the subdev
+	 * is already probed, bound and complete will be called immediately
+	 */
+	ret = rcar_drif_parse_subdevs(sdr);
+	if (ret)
+		goto error;
+
+	sdr->notifier.bound = rcar_drif_notify_bound;
+	sdr->notifier.unbind = rcar_drif_notify_unbind;
+	sdr->notifier.complete = rcar_drif_notify_complete;
+
+	/* Register notifier */
+	ret = v4l2_async_notifier_register(&sdr->v4l2_dev, &sdr->notifier);
+	if (ret < 0) {
+		dev_err(sdr->dev, "failed: notifier register ret %d\n", ret);
+		goto error;
+	}
+
+	return ret;
+
+error:
+	v4l2_device_unregister(&sdr->v4l2_dev);
+
+	return ret;
+}
+
+/* V4L2 SDR device remove */
+static void rcar_drif_sdr_remove(struct rcar_drif_sdr *sdr)
+{
+	v4l2_async_notifier_unregister(&sdr->notifier);
+	v4l2_device_unregister(&sdr->v4l2_dev);
+}
+
+/* DRIF channel probe */
+static int rcar_drif_probe(struct platform_device *pdev)
+{
+	struct rcar_drif_sdr *sdr;
+	struct device_node *np;
+	struct rcar_drif *ch;
+	struct resource	*res;
+	int ret;
+
+	/* Reserve memory for enabled channel */
+	ch = devm_kzalloc(&pdev->dev, sizeof(*ch), GFP_KERNEL);
+	if (!ch)
+		return -ENOMEM;
+
+	ch->pdev = pdev;
+
+	/* Module clock */
+	ch->clk = devm_clk_get(&pdev->dev, "fck");
+	if (IS_ERR(ch->clk)) {
+		ret = PTR_ERR(ch->clk);
+		dev_err(&pdev->dev, "clk get failed (%d)\n", ret);
+		return ret;
+	}
+
+	/* Register map */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	ch->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(ch->base)) {
+		ret = PTR_ERR(ch->base);
+		dev_err(&pdev->dev, "ioremap failed (%d)\n", ret);
+		return ret;
+	}
+	ch->start = res->start;
+	platform_set_drvdata(pdev, ch);
+
+	/* Check if both channels of the bond are enabled */
+	np = rcar_drif_bond_enabled(pdev);
+	if (np) {
+		/* Check if current channel acting as primary-bond */
+		if (!rcar_drif_primary_bond(pdev)) {
+			ch->num = 1;	/* Primary bond is channel 0 always */
+			of_node_put(np);
+			return 0;
+		}
+	}
+
+	/* Reserve memory for SDR structure */
+	sdr = devm_kzalloc(&pdev->dev, sizeof(*sdr), GFP_KERNEL);
+	if (!sdr) {
+		of_node_put(np);
+		return -ENOMEM;
+	}
+	ch->sdr = sdr;
+	sdr->dev = &pdev->dev;
+
+	/* Establish links between SDR and channel(s) */
+	sdr->ch[ch->num] = ch;
+	sdr->hw_ch_mask = BIT(ch->num);
+	if (np) {
+		/* Check if bonded device is ready */
+		ret = rcar_drif_bond_available(sdr, np);
+		of_node_put(np);
+		if (ret)
+			return ret;
+	}
+	sdr->num_hw_ch = hweight_long(sdr->hw_ch_mask);
+
+	return rcar_drif_sdr_probe(sdr);
+}
+
+/* DRIF channel remove */
+static int rcar_drif_remove(struct platform_device *pdev)
+{
+	struct rcar_drif *ch = platform_get_drvdata(pdev);
+	struct rcar_drif_sdr *sdr = ch->sdr;
+
+	/* Channel 0 will be the SDR instance */
+	if (ch->num)
+		return 0;
+
+	/* SDR instance */
+	rcar_drif_sdr_remove(sdr);
+
+	return 0;
+}
+
+/* FIXME: Implement suspend/resume support */
+static int __maybe_unused rcar_drif_suspend(struct device *dev)
+{
+	return 0;
+}
+
+static int __maybe_unused rcar_drif_resume(struct device *dev)
+{
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(rcar_drif_pm_ops, rcar_drif_suspend,
+			 rcar_drif_resume);
+
+static const struct of_device_id rcar_drif_of_table[] = {
+	{ .compatible = "renesas,rcar-gen3-drif" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, rcar_drif_of_table);
+
+#define RCAR_DRIF_DRV_NAME "rcar_drif"
+static struct platform_driver rcar_drif_driver = {
+	.driver = {
+		.name = RCAR_DRIF_DRV_NAME,
+		.of_match_table = of_match_ptr(rcar_drif_of_table),
+		.pm = &rcar_drif_pm_ops,
+		},
+	.probe = rcar_drif_probe,
+	.remove = rcar_drif_remove,
+};
+
+module_platform_driver(rcar_drif_driver);
+
+MODULE_DESCRIPTION("Renesas R-Car Gen3 DRIF driver");
+MODULE_ALIAS("platform:" RCAR_DRIF_DRV_NAME);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Ramesh Shanmugasundaram <ramesh.shanmugasundaram@bp.renesas.com>");