[media] V4L: at91: add Atmel Image Sensor Interface (ISI) support

This patch is to enable Atmel Image Sensor Interface (ISI) driver support.
Signed-off-by: Josh Wu <josh.wu@atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/Kconfig

@@ -945,6 +945,14 @@ config  VIDEO_SAMSUNG_S5P_FIMC
 	  To compile this driver as a module, choose M here: the
 	  module will be called s5p-fimc.
 
+config VIDEO_ATMEL_ISI
+	tristate "ATMEL Image Sensor Interface (ISI) support"
+	depends on VIDEO_DEV && SOC_CAMERA && ARCH_AT91
+	select VIDEOBUF2_DMA_CONTIG
+	---help---
+	  This module makes the ATMEL Image Sensor Interface available
+	  as a v4l2 device.
+
 config VIDEO_S5P_MIPI_CSIS
 	tristate "Samsung S5P and EXYNOS4 MIPI CSI receiver driver"
 	depends on VIDEO_V4L2 && PM_RUNTIME && PLAT_S5P && VIDEO_V4L2_SUBDEV_API

drivers/media/video/Makefile

@@ -167,6 +167,7 @@ obj-$(CONFIG_VIDEO_PXA27x)		+= pxa_camera.o
 obj-$(CONFIG_VIDEO_SH_MOBILE_CSI2)	+= sh_mobile_csi2.o
 obj-$(CONFIG_VIDEO_SH_MOBILE_CEU)	+= sh_mobile_ceu_camera.o
 obj-$(CONFIG_VIDEO_OMAP1)		+= omap1_camera.o
+obj-$(CONFIG_VIDEO_ATMEL_ISI)		+= atmel-isi.o
 
 obj-$(CONFIG_VIDEO_SAMSUNG_S5P_FIMC) 	+= s5p-fimc/
 

drivers/media/video/atmel-isi.c

+/*
+ * Copyright (c) 2011 Atmel Corporation
+ * Josh Wu, <josh.wu@atmel.com>
+ *
+ * Based on previous work by Lars Haring, <lars.haring@atmel.com>
+ * and Sedji Gaouaou
+ * Based on the bttv driver for Bt848 with respective copyright holders
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include <media/atmel-isi.h>
+#include <media/soc_camera.h>
+#include <media/soc_mediabus.h>
+#include <media/videobuf2-dma-contig.h>
+
+#define MAX_BUFFER_NUM			32
+#define MAX_SUPPORT_WIDTH		2048
+#define MAX_SUPPORT_HEIGHT		2048
+#define VID_LIMIT_BYTES			(16 * 1024 * 1024)
+#define MIN_FRAME_RATE			15
+#define FRAME_INTERVAL_MILLI_SEC	(1000 / MIN_FRAME_RATE)
+
+/* ISI states */
+enum {
+	ISI_STATE_IDLE = 0,
+	ISI_STATE_READY,
+	ISI_STATE_WAIT_SOF,
+};
+
+/* Frame buffer descriptor */
+struct fbd {
+	/* Physical address of the frame buffer */
+	u32 fb_address;
+	/* DMA Control Register(only in HISI2) */
+	u32 dma_ctrl;
+	/* Physical address of the next fbd */
+	u32 next_fbd_address;
+};
+
+static void set_dma_ctrl(struct fbd *fb_desc, u32 ctrl)
+{
+	fb_desc->dma_ctrl = ctrl;
+}
+
+struct isi_dma_desc {
+	struct list_head list;
+	struct fbd *p_fbd;
+	u32 fbd_phys;
+};
+
+/* Frame buffer data */
+struct frame_buffer {
+	struct vb2_buffer vb;
+	struct isi_dma_desc *p_dma_desc;
+	struct list_head list;
+};
+
+struct atmel_isi {
+	/* Protects the access of variables shared with the ISR */
+	spinlock_t			lock;
+	void __iomem			*regs;
+
+	int				sequence;
+	/* State of the ISI module in capturing mode */
+	int				state;
+
+	/* Wait queue for waiting for SOF */
+	wait_queue_head_t		vsync_wq;
+
+	struct vb2_alloc_ctx		*alloc_ctx;
+
+	/* Allocate descriptors for dma buffer use */
+	struct fbd			*p_fb_descriptors;
+	u32				fb_descriptors_phys;
+	struct				list_head dma_desc_head;
+	struct isi_dma_desc		dma_desc[MAX_BUFFER_NUM];
+
+	struct completion		complete;
+	struct clk			*pclk;
+	unsigned int			irq;
+
+	struct isi_platform_data	*pdata;
+
+	struct list_head		video_buffer_list;
+	struct frame_buffer		*active;
+
+	struct soc_camera_device	*icd;
+	struct soc_camera_host		soc_host;
+};
+
+static void isi_writel(struct atmel_isi *isi, u32 reg, u32 val)
+{
+	writel(val, isi->regs + reg);
+}
+static u32 isi_readl(struct atmel_isi *isi, u32 reg)
+{
+	return readl(isi->regs + reg);
+}
+
+static int configure_geometry(struct atmel_isi *isi, u32 width,
+			u32 height, enum v4l2_mbus_pixelcode code)
+{
+	u32 cfg2, cr;
+
+	switch (code) {
+	/* YUV, including grey */
+	case V4L2_MBUS_FMT_Y8_1X8:
+		cr = ISI_CFG2_GRAYSCALE;
+		break;
+	case V4L2_MBUS_FMT_UYVY8_2X8:
+		cr = ISI_CFG2_YCC_SWAP_MODE_3;
+		break;
+	case V4L2_MBUS_FMT_VYUY8_2X8:
+		cr = ISI_CFG2_YCC_SWAP_MODE_2;
+		break;
+	case V4L2_MBUS_FMT_YUYV8_2X8:
+		cr = ISI_CFG2_YCC_SWAP_MODE_1;
+		break;
+	case V4L2_MBUS_FMT_YVYU8_2X8:
+		cr = ISI_CFG2_YCC_SWAP_DEFAULT;
+		break;
+	/* RGB, TODO */
+	default:
+		return -EINVAL;
+	}
+
+	isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
+
+	cfg2 = isi_readl(isi, ISI_CFG2);
+	cfg2 |= cr;
+	/* Set width */
+	cfg2 &= ~(ISI_CFG2_IM_HSIZE_MASK);
+	cfg2 |= ((width - 1) << ISI_CFG2_IM_HSIZE_OFFSET) &
+			ISI_CFG2_IM_HSIZE_MASK;
+	/* Set height */
+	cfg2 &= ~(ISI_CFG2_IM_VSIZE_MASK);
+	cfg2 |= ((height - 1) << ISI_CFG2_IM_VSIZE_OFFSET)
+			& ISI_CFG2_IM_VSIZE_MASK;
+	isi_writel(isi, ISI_CFG2, cfg2);
+
+	return 0;
+}
+
+static irqreturn_t atmel_isi_handle_streaming(struct atmel_isi *isi)
+{
+	if (isi->active) {
+		struct vb2_buffer *vb = &isi->active->vb;
+		struct frame_buffer *buf = isi->active;
+
+		list_del_init(&buf->list);
+		do_gettimeofday(&vb->v4l2_buf.timestamp);
+		vb->v4l2_buf.sequence = isi->sequence++;
+		vb2_buffer_done(vb, VB2_BUF_STATE_DONE);
+	}
+
+	if (list_empty(&isi->video_buffer_list)) {
+		isi->active = NULL;
+	} else {
+		/* start next dma frame. */
+		isi->active = list_entry(isi->video_buffer_list.next,
+					struct frame_buffer, list);
+		isi_writel(isi, ISI_DMA_C_DSCR,
+			isi->active->p_dma_desc->fbd_phys);
+		isi_writel(isi, ISI_DMA_C_CTRL,
+			ISI_DMA_CTRL_FETCH | ISI_DMA_CTRL_DONE);
+		isi_writel(isi, ISI_DMA_CHER, ISI_DMA_CHSR_C_CH);
+	}
+	return IRQ_HANDLED;
+}
+
+/* ISI interrupt service routine */
+static irqreturn_t isi_interrupt(int irq, void *dev_id)
+{
+	struct atmel_isi *isi = dev_id;
+	u32 status, mask, pending;
+	irqreturn_t ret = IRQ_NONE;
+
+	spin_lock(&isi->lock);
+
+	status = isi_readl(isi, ISI_STATUS);
+	mask = isi_readl(isi, ISI_INTMASK);
+	pending = status & mask;
+
+	if (pending & ISI_CTRL_SRST) {
+		complete(&isi->complete);
+		isi_writel(isi, ISI_INTDIS, ISI_CTRL_SRST);
+		ret = IRQ_HANDLED;
+	} else if (pending & ISI_CTRL_DIS) {
+		complete(&isi->complete);
+		isi_writel(isi, ISI_INTDIS, ISI_CTRL_DIS);
+		ret = IRQ_HANDLED;
+	} else {
+		if ((pending & ISI_SR_VSYNC) &&
+				(isi->state == ISI_STATE_IDLE)) {
+			isi->state = ISI_STATE_READY;
+			wake_up_interruptible(&isi->vsync_wq);
+			ret = IRQ_HANDLED;
+		}
+		if (likely(pending & ISI_SR_CXFR_DONE))
+			ret = atmel_isi_handle_streaming(isi);
+	}
+
+	spin_unlock(&isi->lock);
+	return ret;
+}
+
+#define	WAIT_ISI_RESET		1
+#define	WAIT_ISI_DISABLE	0
+static int atmel_isi_wait_status(struct atmel_isi *isi, int wait_reset)
+{
+	unsigned long timeout;
+	/*
+	 * The reset or disable will only succeed if we have a
+	 * pixel clock from the camera.
+	 */
+	init_completion(&isi->complete);
+
+	if (wait_reset) {
+		isi_writel(isi, ISI_INTEN, ISI_CTRL_SRST);
+		isi_writel(isi, ISI_CTRL, ISI_CTRL_SRST);
+	} else {
+		isi_writel(isi, ISI_INTEN, ISI_CTRL_DIS);
+		isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
+	}
+
+	timeout = wait_for_completion_timeout(&isi->complete,
+			msecs_to_jiffies(100));
+	if (timeout == 0)
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+/* ------------------------------------------------------------------
+	Videobuf operations
+   ------------------------------------------------------------------*/
+static int queue_setup(struct vb2_queue *vq, unsigned int *nbuffers,
+				unsigned int *nplanes, unsigned long sizes[],
+				void *alloc_ctxs[])
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(vq);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	unsigned long size;
+	int ret, bytes_per_line;
+
+	/* Reset ISI */
+	ret = atmel_isi_wait_status(isi, WAIT_ISI_RESET);
+	if (ret < 0) {
+		dev_err(icd->dev.parent, "Reset ISI timed out\n");
+		return ret;
+	}
+	/* Disable all interrupts */
+	isi_writel(isi, ISI_INTDIS, ~0UL);
+
+	bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
+						icd->current_fmt->host_fmt);
+
+	if (bytes_per_line < 0)
+		return bytes_per_line;
+
+	size = bytes_per_line * icd->user_height;
+
+	if (!*nbuffers || *nbuffers > MAX_BUFFER_NUM)
+		*nbuffers = MAX_BUFFER_NUM;
+
+	if (size * *nbuffers > VID_LIMIT_BYTES)
+		*nbuffers = VID_LIMIT_BYTES / size;
+
+	*nplanes = 1;
+	sizes[0] = size;
+	alloc_ctxs[0] = isi->alloc_ctx;
+
+	isi->sequence = 0;
+	isi->active = NULL;
+
+	dev_dbg(icd->dev.parent, "%s, count=%d, size=%ld\n", __func__,
+		*nbuffers, size);
+
+	return 0;
+}
+
+static int buffer_init(struct vb2_buffer *vb)
+{
+	struct frame_buffer *buf = container_of(vb, struct frame_buffer, vb);
+
+	buf->p_dma_desc = NULL;
+	INIT_LIST_HEAD(&buf->list);
+
+	return 0;
+}
+
+static int buffer_prepare(struct vb2_buffer *vb)
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(vb->vb2_queue);
+	struct frame_buffer *buf = container_of(vb, struct frame_buffer, vb);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	unsigned long size;
+	struct isi_dma_desc *desc;
+	int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
+						icd->current_fmt->host_fmt);
+
+	if (bytes_per_line < 0)
+		return bytes_per_line;
+
+	size = bytes_per_line * icd->user_height;
+
+	if (vb2_plane_size(vb, 0) < size) {
+		dev_err(icd->dev.parent, "%s data will not fit into plane (%lu < %lu)\n",
+				__func__, vb2_plane_size(vb, 0), size);
+		return -EINVAL;
+	}
+
+	vb2_set_plane_payload(&buf->vb, 0, size);
+
+	if (!buf->p_dma_desc) {
+		if (list_empty(&isi->dma_desc_head)) {
+			dev_err(icd->dev.parent, "Not enough dma descriptors.\n");
+			return -EINVAL;
+		} else {
+			/* Get an available descriptor */
+			desc = list_entry(isi->dma_desc_head.next,
+						struct isi_dma_desc, list);
+			/* Delete the descriptor since now it is used */
+			list_del_init(&desc->list);
+
+			/* Initialize the dma descriptor */
+			desc->p_fbd->fb_address =
+					vb2_dma_contig_plane_paddr(vb, 0);
+			desc->p_fbd->next_fbd_address = 0;
+			set_dma_ctrl(desc->p_fbd, ISI_DMA_CTRL_WB);
+
+			buf->p_dma_desc = desc;
+		}
+	}
+	return 0;
+}
+
+static void buffer_cleanup(struct vb2_buffer *vb)
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(vb->vb2_queue);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	struct frame_buffer *buf = container_of(vb, struct frame_buffer, vb);
+
+	/* This descriptor is available now and we add to head list */
+	if (buf->p_dma_desc)
+		list_add(&buf->p_dma_desc->list, &isi->dma_desc_head);
+}
+
+static void start_dma(struct atmel_isi *isi, struct frame_buffer *buffer)
+{
+	u32 ctrl, cfg1;
+
+	cfg1 = isi_readl(isi, ISI_CFG1);
+	/* Enable irq: cxfr for the codec path, pxfr for the preview path */
+	isi_writel(isi, ISI_INTEN,
+			ISI_SR_CXFR_DONE | ISI_SR_PXFR_DONE);
+
+	/* Check if already in a frame */
+	if (isi_readl(isi, ISI_STATUS) & ISI_CTRL_CDC) {
+		dev_err(isi->icd->dev.parent, "Already in frame handling.\n");
+		return;
+	}
+
+	isi_writel(isi, ISI_DMA_C_DSCR, buffer->p_dma_desc->fbd_phys);
+	isi_writel(isi, ISI_DMA_C_CTRL, ISI_DMA_CTRL_FETCH | ISI_DMA_CTRL_DONE);
+	isi_writel(isi, ISI_DMA_CHER, ISI_DMA_CHSR_C_CH);
+
+	/* Enable linked list */
+	cfg1 |= isi->pdata->frate | ISI_CFG1_DISCR;
+
+	/* Enable codec path and ISI */
+	ctrl = ISI_CTRL_CDC | ISI_CTRL_EN;
+	isi_writel(isi, ISI_CTRL, ctrl);
+	isi_writel(isi, ISI_CFG1, cfg1);
+}
+
+static void buffer_queue(struct vb2_buffer *vb)
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(vb->vb2_queue);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	struct frame_buffer *buf = container_of(vb, struct frame_buffer, vb);
+	unsigned long flags = 0;
+
+	spin_lock_irqsave(&isi->lock, flags);
+	list_add_tail(&buf->list, &isi->video_buffer_list);
+
+	if (isi->active == NULL) {
+		isi->active = buf;
+		start_dma(isi, buf);
+	}
+	spin_unlock_irqrestore(&isi->lock, flags);
+}
+
+static int start_streaming(struct vb2_queue *vq)
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(vq);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+
+	u32 sr = 0;
+	int ret;
+
+	spin_lock_irq(&isi->lock);
+	isi->state = ISI_STATE_IDLE;
+	/* Clear any pending SOF interrupt */
+	sr = isi_readl(isi, ISI_STATUS);
+	/* Enable VSYNC interrupt for SOF */
+	isi_writel(isi, ISI_INTEN, ISI_SR_VSYNC);
+	isi_writel(isi, ISI_CTRL, ISI_CTRL_EN);
+	spin_unlock_irq(&isi->lock);
+
+	dev_dbg(icd->dev.parent, "Waiting for SOF\n");
+	ret = wait_event_interruptible(isi->vsync_wq,
+				       isi->state != ISI_STATE_IDLE);
+	if (ret)
+		return ret;
+
+	if (isi->state != ISI_STATE_READY)
+		return -EIO;
+
+	spin_lock_irq(&isi->lock);
+	isi->state = ISI_STATE_WAIT_SOF;
+	isi_writel(isi, ISI_INTDIS, ISI_SR_VSYNC);
+	spin_unlock_irq(&isi->lock);
+
+	return 0;
+}
+
+/* abort streaming and wait for last buffer */
+static int stop_streaming(struct vb2_queue *vq)
+{
+	struct soc_camera_device *icd = soc_camera_from_vb2q(vq);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	struct frame_buffer *buf, *node;
+	int ret = 0;
+	unsigned long timeout;
+
+	spin_lock_irq(&isi->lock);
+	isi->active = NULL;
+	/* Release all active buffers */
+	list_for_each_entry_safe(buf, node, &isi->video_buffer_list, list) {
+		list_del_init(&buf->list);
+		vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
+	}
+	spin_unlock_irq(&isi->lock);
+
+	timeout = jiffies + FRAME_INTERVAL_MILLI_SEC * HZ;
+	/* Wait until the end of the current frame. */
+	while ((isi_readl(isi, ISI_STATUS) & ISI_CTRL_CDC) &&
+			time_before(jiffies, timeout))
+		msleep(1);
+
+	if (time_after(jiffies, timeout)) {
+		dev_err(icd->dev.parent,
+			"Timeout waiting for finishing codec request\n");
+		return -ETIMEDOUT;
+	}
+
+	/* Disable interrupts */
+	isi_writel(isi, ISI_INTDIS,
+			ISI_SR_CXFR_DONE | ISI_SR_PXFR_DONE);
+
+	/* Disable ISI and wait for it is done */
+	ret = atmel_isi_wait_status(isi, WAIT_ISI_DISABLE);
+	if (ret < 0)
+		dev_err(icd->dev.parent, "Disable ISI timed out\n");
+
+	return ret;
+}
+
+static struct vb2_ops isi_video_qops = {
+	.queue_setup		= queue_setup,
+	.buf_init		= buffer_init,
+	.buf_prepare		= buffer_prepare,
+	.buf_cleanup		= buffer_cleanup,
+	.buf_queue		= buffer_queue,
+	.start_streaming	= start_streaming,
+	.stop_streaming		= stop_streaming,
+	.wait_prepare		= soc_camera_unlock,
+	.wait_finish		= soc_camera_lock,
+};
+
+/* ------------------------------------------------------------------
+	SOC camera operations for the device
+   ------------------------------------------------------------------*/
+static int isi_camera_init_videobuf(struct vb2_queue *q,
+				     struct soc_camera_device *icd)
+{
+	q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+	q->io_modes = VB2_MMAP;
+	q->drv_priv = icd;
+	q->buf_struct_size = sizeof(struct frame_buffer);
+	q->ops = &isi_video_qops;
+	q->mem_ops = &vb2_dma_contig_memops;
+
+	return vb2_queue_init(q);
+}
+
+static int isi_camera_set_fmt(struct soc_camera_device *icd,
+			      struct v4l2_format *f)
+{
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
+	const struct soc_camera_format_xlate *xlate;
+	struct v4l2_pix_format *pix = &f->fmt.pix;
+	struct v4l2_mbus_framefmt mf;
+	int ret;
+
+	xlate = soc_camera_xlate_by_fourcc(icd, pix->pixelformat);
+	if (!xlate) {
+		dev_warn(icd->dev.parent, "Format %x not found\n",
+			 pix->pixelformat);
+		return -EINVAL;
+	}
+
+	dev_dbg(icd->dev.parent, "Plan to set format %dx%d\n",
+			pix->width, pix->height);
+
+	mf.width	= pix->width;
+	mf.height	= pix->height;
+	mf.field	= pix->field;
+	mf.colorspace	= pix->colorspace;
+	mf.code		= xlate->code;
+
+	ret = v4l2_subdev_call(sd, video, s_mbus_fmt, &mf);
+	if (ret < 0)
+		return ret;
+
+	if (mf.code != xlate->code)
+		return -EINVAL;
+
+	ret = configure_geometry(isi, pix->width, pix->height, xlate->code);
+	if (ret < 0)
+		return ret;
+
+	pix->width		= mf.width;
+	pix->height		= mf.height;
+	pix->field		= mf.field;
+	pix->colorspace		= mf.colorspace;
+	icd->current_fmt	= xlate;
+
+	dev_dbg(icd->dev.parent, "Finally set format %dx%d\n",
+		pix->width, pix->height);
+
+	return ret;
+}
+
+static int isi_camera_try_fmt(struct soc_camera_device *icd,
+			      struct v4l2_format *f)
+{
+	struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
+	const struct soc_camera_format_xlate *xlate;
+	struct v4l2_pix_format *pix = &f->fmt.pix;
+	struct v4l2_mbus_framefmt mf;
+	u32 pixfmt = pix->pixelformat;
+	int ret;
+
+	xlate = soc_camera_xlate_by_fourcc(icd, pixfmt);
+	if (pixfmt && !xlate) {
+		dev_warn(icd->dev.parent, "Format %x not found\n", pixfmt);
+		return -EINVAL;
+	}
+
+	/* limit to Atmel ISI hardware capabilities */
+	if (pix->height > MAX_SUPPORT_HEIGHT)
+		pix->height = MAX_SUPPORT_HEIGHT;
+	if (pix->width > MAX_SUPPORT_WIDTH)
+		pix->width = MAX_SUPPORT_WIDTH;
+
+	/* limit to sensor capabilities */
+	mf.width	= pix->width;
+	mf.height	= pix->height;
+	mf.field	= pix->field;
+	mf.colorspace	= pix->colorspace;
+	mf.code		= xlate->code;
+
+	ret = v4l2_subdev_call(sd, video, try_mbus_fmt, &mf);
+	if (ret < 0)
+		return ret;
+
+	pix->width	= mf.width;
+	pix->height	= mf.height;
+	pix->colorspace	= mf.colorspace;
+
+	switch (mf.field) {
+	case V4L2_FIELD_ANY:
+		pix->field = V4L2_FIELD_NONE;
+		break;
+	case V4L2_FIELD_NONE:
+		break;
+	default:
+		dev_err(icd->dev.parent, "Field type %d unsupported.\n",
+			mf.field);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct soc_mbus_pixelfmt isi_camera_formats[] = {
+	{
+		.fourcc			= V4L2_PIX_FMT_YUYV,
+		.name			= "Packed YUV422 16 bit",
+		.bits_per_sample	= 8,
+		.packing		= SOC_MBUS_PACKING_2X8_PADHI,
+		.order			= SOC_MBUS_ORDER_LE,
+	},
+};
+
+/* This will be corrected as we get more formats */
+static bool isi_camera_packing_supported(const struct soc_mbus_pixelfmt *fmt)
+{
+	return	fmt->packing == SOC_MBUS_PACKING_NONE ||
+		(fmt->bits_per_sample == 8 &&
+		 fmt->packing == SOC_MBUS_PACKING_2X8_PADHI) ||
+		(fmt->bits_per_sample > 8 &&
+		 fmt->packing == SOC_MBUS_PACKING_EXTEND16);
+}
+
+static unsigned long make_bus_param(struct atmel_isi *isi)
+{
+	unsigned long flags;
+	/*
+	 * Platform specified synchronization and pixel clock polarities are
+	 * only a recommendation and are only used during probing. Atmel ISI
+	 * camera interface only works in master mode, i.e., uses HSYNC and
+	 * VSYNC signals from the sensor
+	 */
+	flags = SOCAM_MASTER |
+		SOCAM_HSYNC_ACTIVE_HIGH |
+		SOCAM_HSYNC_ACTIVE_LOW |
+		SOCAM_VSYNC_ACTIVE_HIGH |
+		SOCAM_VSYNC_ACTIVE_LOW |
+		SOCAM_PCLK_SAMPLE_RISING |
+		SOCAM_PCLK_SAMPLE_FALLING |
+		SOCAM_DATA_ACTIVE_HIGH;
+
+	if (isi->pdata->data_width_flags & ISI_DATAWIDTH_10)
+		flags |= SOCAM_DATAWIDTH_10;
+
+	if (isi->pdata->data_width_flags & ISI_DATAWIDTH_8)
+		flags |= SOCAM_DATAWIDTH_8;
+
+	if (flags & SOCAM_DATAWIDTH_MASK)
+		return flags;
+
+	return 0;
+}
+
+static int isi_camera_try_bus_param(struct soc_camera_device *icd,
+				    unsigned char buswidth)
+{
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	unsigned long camera_flags;
+	int ret;
+
+	camera_flags = icd->ops->query_bus_param(icd);
+	ret = soc_camera_bus_param_compatible(camera_flags,
+					make_bus_param(isi));
+	if (!ret)
+		return -EINVAL;
+	return 0;
+}
+
+
+static int isi_camera_get_formats(struct soc_camera_device *icd,
+				  unsigned int idx,
+				  struct soc_camera_format_xlate *xlate)
+{
+	struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
+	int formats = 0, ret;
+	/* sensor format */
+	enum v4l2_mbus_pixelcode code;
+	/* soc camera host format */
+	const struct soc_mbus_pixelfmt *fmt;
+
+	ret = v4l2_subdev_call(sd, video, enum_mbus_fmt, idx, &code);
+	if (ret < 0)
+		/* No more formats */
+		return 0;
+
+	fmt = soc_mbus_get_fmtdesc(code);
+	if (!fmt) {
+		dev_err(icd->dev.parent,
+			"Invalid format code #%u: %d\n", idx, code);
+		return 0;
+	}
+
+	/* This also checks support for the requested bits-per-sample */
+	ret = isi_camera_try_bus_param(icd, fmt->bits_per_sample);
+	if (ret < 0) {
+		dev_err(icd->dev.parent,
+			"Fail to try the bus parameters.\n");
+		return 0;
+	}
+
+	switch (code) {
+	case V4L2_MBUS_FMT_UYVY8_2X8:
+	case V4L2_MBUS_FMT_VYUY8_2X8:
+	case V4L2_MBUS_FMT_YUYV8_2X8:
+	case V4L2_MBUS_FMT_YVYU8_2X8:
+		formats++;
+		if (xlate) {
+			xlate->host_fmt	= &isi_camera_formats[0];
+			xlate->code	= code;
+			xlate++;
+			dev_dbg(icd->dev.parent, "Providing format %s using code %d\n",
+				isi_camera_formats[0].name, code);
+		}
+		break;
+	default:
+		if (!isi_camera_packing_supported(fmt))
+			return 0;
+		if (xlate)
+			dev_dbg(icd->dev.parent,
+				"Providing format %s in pass-through mode\n",
+				fmt->name);
+	}
+
+	/* Generic pass-through */
+	formats++;
+	if (xlate) {
+		xlate->host_fmt	= fmt;
+		xlate->code	= code;
+		xlate++;
+	}
+
+	return formats;
+}
+
+/* Called with .video_lock held */
+static int isi_camera_add_device(struct soc_camera_device *icd)
+{
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	int ret;
+
+	if (isi->icd)
+		return -EBUSY;
+
+	ret = clk_enable(isi->pclk);
+	if (ret)
+		return ret;
+
+	isi->icd = icd;
+	dev_dbg(icd->dev.parent, "Atmel ISI Camera driver attached to camera %d\n",
+		 icd->devnum);
+	return 0;
+}
+/* Called with .video_lock held */
+static void isi_camera_remove_device(struct soc_camera_device *icd)
+{
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+
+	BUG_ON(icd != isi->icd);
+
+	clk_disable(isi->pclk);
+	isi->icd = NULL;
+
+	dev_dbg(icd->dev.parent, "Atmel ISI Camera driver detached from camera %d\n",
+		 icd->devnum);
+}
+
+static unsigned int isi_camera_poll(struct file *file, poll_table *pt)
+{
+	struct soc_camera_device *icd = file->private_data;
+
+	return vb2_poll(&icd->vb2_vidq, file, pt);
+}
+
+static int isi_camera_querycap(struct soc_camera_host *ici,
+			       struct v4l2_capability *cap)
+{
+	strcpy(cap->driver, "atmel-isi");
+	strcpy(cap->card, "Atmel Image Sensor Interface");
+	cap->capabilities = (V4L2_CAP_VIDEO_CAPTURE |
+				V4L2_CAP_STREAMING);
+	return 0;
+}
+
+static int isi_camera_set_bus_param(struct soc_camera_device *icd, u32 pixfmt)
+{
+	struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent);
+	struct atmel_isi *isi = ici->priv;
+	unsigned long bus_flags, camera_flags, common_flags;
+	int ret;
+	u32 cfg1 = 0;
+
+	camera_flags = icd->ops->query_bus_param(icd);
+
+	bus_flags = make_bus_param(isi);
+	common_flags = soc_camera_bus_param_compatible(camera_flags, bus_flags);
+	dev_dbg(icd->dev.parent, "Flags cam: 0x%lx host: 0x%lx common: 0x%lx\n",
+		camera_flags, bus_flags, common_flags);
+	if (!common_flags)
+		return -EINVAL;
+
+	/* Make choises, based on platform preferences */
+	if ((common_flags & SOCAM_HSYNC_ACTIVE_HIGH) &&
+	    (common_flags & SOCAM_HSYNC_ACTIVE_LOW)) {
+		if (isi->pdata->hsync_act_low)
+			common_flags &= ~SOCAM_HSYNC_ACTIVE_HIGH;
+		else
+			common_flags &= ~SOCAM_HSYNC_ACTIVE_LOW;
+	}
+
+	if ((common_flags & SOCAM_VSYNC_ACTIVE_HIGH) &&
+	    (common_flags & SOCAM_VSYNC_ACTIVE_LOW)) {
+		if (isi->pdata->vsync_act_low)
+			common_flags &= ~SOCAM_VSYNC_ACTIVE_HIGH;
+		else
+			common_flags &= ~SOCAM_VSYNC_ACTIVE_LOW;
+	}
+
+	if ((common_flags & SOCAM_PCLK_SAMPLE_RISING) &&
+	    (common_flags & SOCAM_PCLK_SAMPLE_FALLING)) {
+		if (isi->pdata->pclk_act_falling)
+			common_flags &= ~SOCAM_PCLK_SAMPLE_RISING;
+		else
+			common_flags &= ~SOCAM_PCLK_SAMPLE_FALLING;
+	}
+
+	ret = icd->ops->set_bus_param(icd, common_flags);
+	if (ret < 0) {
+		dev_dbg(icd->dev.parent, "Camera set_bus_param(%lx) returned %d\n",
+			common_flags, ret);
+		return ret;
+	}
+
+	/* set bus param for ISI */
+	if (common_flags & SOCAM_HSYNC_ACTIVE_LOW)
+		cfg1 |= ISI_CFG1_HSYNC_POL_ACTIVE_LOW;
+	if (common_flags & SOCAM_VSYNC_ACTIVE_LOW)
+		cfg1 |= ISI_CFG1_VSYNC_POL_ACTIVE_LOW;
+	if (common_flags & SOCAM_PCLK_SAMPLE_FALLING)
+		cfg1 |= ISI_CFG1_PIXCLK_POL_ACTIVE_FALLING;
+
+	if (isi->pdata->has_emb_sync)
+		cfg1 |= ISI_CFG1_EMB_SYNC;
+	if (isi->pdata->isi_full_mode)
+		cfg1 |= ISI_CFG1_FULL_MODE;
+
+	isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
+	isi_writel(isi, ISI_CFG1, cfg1);
+
+	return 0;
+}
+
+static struct soc_camera_host_ops isi_soc_camera_host_ops = {
+	.owner		= THIS_MODULE,
+	.add		= isi_camera_add_device,
+	.remove		= isi_camera_remove_device,
+	.set_fmt	= isi_camera_set_fmt,
+	.try_fmt	= isi_camera_try_fmt,
+	.get_formats	= isi_camera_get_formats,
+	.init_videobuf2	= isi_camera_init_videobuf,
+	.poll		= isi_camera_poll,
+	.querycap	= isi_camera_querycap,
+	.set_bus_param	= isi_camera_set_bus_param,
+};
+
+/* -----------------------------------------------------------------------*/
+static int __devexit atmel_isi_remove(struct platform_device *pdev)
+{
+	struct soc_camera_host *soc_host = to_soc_camera_host(&pdev->dev);
+	struct atmel_isi *isi = container_of(soc_host,
+					struct atmel_isi, soc_host);
+
+	free_irq(isi->irq, isi);
+	soc_camera_host_unregister(soc_host);
+	vb2_dma_contig_cleanup_ctx(isi->alloc_ctx);
+	dma_free_coherent(&pdev->dev,
+			sizeof(struct fbd) * MAX_BUFFER_NUM,
+			isi->p_fb_descriptors,
+			isi->fb_descriptors_phys);
+
+	iounmap(isi->regs);
+	clk_put(isi->pclk);
+	kfree(isi);
+
+	return 0;
+}
+
+static int __devinit atmel_isi_probe(struct platform_device *pdev)
+{
+	unsigned int irq;
+	struct atmel_isi *isi;
+	struct clk *pclk;
+	struct resource *regs;
+	int ret, i;
+	struct device *dev = &pdev->dev;
+	struct soc_camera_host *soc_host;
+	struct isi_platform_data *pdata;
+
+	pdata = dev->platform_data;
+	if (!pdata || !pdata->data_width_flags) {
+		dev_err(&pdev->dev,
+			"No config available for Atmel ISI\n");
+		return -EINVAL;
+	}
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!regs)
+		return -ENXIO;
+
+	pclk = clk_get(&pdev->dev, "isi_clk");
+	if (IS_ERR(pclk))
+		return PTR_ERR(pclk);
+
+	isi = kzalloc(sizeof(struct atmel_isi), GFP_KERNEL);
+	if (!isi) {
+		ret = -ENOMEM;
+		dev_err(&pdev->dev, "Can't allocate interface!\n");
+		goto err_alloc_isi;
+	}
+
+	isi->pclk = pclk;
+	isi->pdata = pdata;
+	isi->active = NULL;
+	spin_lock_init(&isi->lock);
+	init_waitqueue_head(&isi->vsync_wq);
+	INIT_LIST_HEAD(&isi->video_buffer_list);
+	INIT_LIST_HEAD(&isi->dma_desc_head);
+
+	isi->p_fb_descriptors = dma_alloc_coherent(&pdev->dev,
+				sizeof(struct fbd) * MAX_BUFFER_NUM,
+				&isi->fb_descriptors_phys,
+				GFP_KERNEL);
+	if (!isi->p_fb_descriptors) {
+		ret = -ENOMEM;
+		dev_err(&pdev->dev, "Can't allocate descriptors!\n");
+		goto err_alloc_descriptors;
+	}
+
+	for (i = 0; i < MAX_BUFFER_NUM; i++) {
+		isi->dma_desc[i].p_fbd = isi->p_fb_descriptors + i;
+		isi->dma_desc[i].fbd_phys = isi->fb_descriptors_phys +
+					i * sizeof(struct fbd);
+		list_add(&isi->dma_desc[i].list, &isi->dma_desc_head);
+	}
+
+	isi->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev);
+	if (IS_ERR(isi->alloc_ctx)) {
+		ret = PTR_ERR(isi->alloc_ctx);
+		goto err_alloc_ctx;
+	}
+
+	isi->regs = ioremap(regs->start, resource_size(regs));
+	if (!isi->regs) {
+		ret = -ENOMEM;
+		goto err_ioremap;
+	}
+
+	isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		ret = irq;
+		goto err_req_irq;
+	}
+
+	ret = request_irq(irq, isi_interrupt, 0, "isi", isi);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to request irq %d\n", irq);
+		goto err_req_irq;
+	}
+	isi->irq = irq;
+
+	soc_host		= &isi->soc_host;
+	soc_host->drv_name	= "isi-camera";
+	soc_host->ops		= &isi_soc_camera_host_ops;
+	soc_host->priv		= isi;
+	soc_host->v4l2_dev.dev	= &pdev->dev;
+	soc_host->nr		= pdev->id;
+
+	ret = soc_camera_host_register(soc_host);
+	if (ret) {
+		dev_err(&pdev->dev, "Unable to register soc camera host\n");
+		goto err_register_soc_camera_host;
+	}
+	return 0;
+
+err_register_soc_camera_host:
+	free_irq(isi->irq, isi);
+err_req_irq:
+	iounmap(isi->regs);
+err_ioremap:
+	vb2_dma_contig_cleanup_ctx(isi->alloc_ctx);
+err_alloc_ctx:
+	dma_free_coherent(&pdev->dev,
+			sizeof(struct fbd) * MAX_BUFFER_NUM,
+			isi->p_fb_descriptors,
+			isi->fb_descriptors_phys);
+err_alloc_descriptors:
+	kfree(isi);
+err_alloc_isi:
+	clk_put(isi->pclk);
+
+	return ret;
+}
+
+static struct platform_driver atmel_isi_driver = {
+	.probe		= atmel_isi_probe,
+	.remove		= __devexit_p(atmel_isi_remove),
+	.driver		= {
+		.name = "atmel_isi",
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init atmel_isi_init_module(void)
+{
+	return  platform_driver_probe(&atmel_isi_driver, &atmel_isi_probe);
+}
+
+static void __exit atmel_isi_exit(void)
+{
+	platform_driver_unregister(&atmel_isi_driver);
+}
+module_init(atmel_isi_init_module);
+module_exit(atmel_isi_exit);
+
+MODULE_AUTHOR("Josh Wu <josh.wu@atmel.com>");
+MODULE_DESCRIPTION("The V4L2 driver for Atmel Linux");
+MODULE_LICENSE("GPL");
+MODULE_SUPPORTED_DEVICE("video");

include/media/atmel-isi.h

+/*
+ * Register definitions for the Atmel Image Sensor Interface.
+ *
+ * Copyright (C) 2011 Atmel Corporation
+ * Josh Wu, <josh.wu@atmel.com>
+ *
+ * Based on previous work by Lars Haring, <lars.haring@atmel.com>
+ * and Sedji Gaouaou
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ATMEL_ISI_H__
+#define __ATMEL_ISI_H__
+
+#include <linux/types.h>
+
+/* ISI_V2 register offsets */
+#define ISI_CFG1				0x0000
+#define ISI_CFG2				0x0004
+#define ISI_PSIZE				0x0008
+#define ISI_PDECF				0x000c
+#define ISI_Y2R_SET0				0x0010
+#define ISI_Y2R_SET1				0x0014
+#define ISI_R2Y_SET0				0x0018
+#define ISI_R2Y_SET1				0x001C
+#define ISI_R2Y_SET2				0x0020
+#define ISI_CTRL				0x0024
+#define ISI_STATUS				0x0028
+#define ISI_INTEN				0x002C
+#define ISI_INTDIS				0x0030
+#define ISI_INTMASK				0x0034
+#define ISI_DMA_CHER				0x0038
+#define ISI_DMA_CHDR				0x003C
+#define ISI_DMA_CHSR				0x0040
+#define ISI_DMA_P_ADDR				0x0044
+#define ISI_DMA_P_CTRL				0x0048
+#define ISI_DMA_P_DSCR				0x004C
+#define ISI_DMA_C_ADDR				0x0050
+#define ISI_DMA_C_CTRL				0x0054
+#define ISI_DMA_C_DSCR				0x0058
+
+/* Bitfields in CFG1 */
+#define ISI_CFG1_HSYNC_POL_ACTIVE_LOW		(1 << 2)
+#define ISI_CFG1_VSYNC_POL_ACTIVE_LOW		(1 << 3)
+#define ISI_CFG1_PIXCLK_POL_ACTIVE_FALLING	(1 << 4)
+#define ISI_CFG1_EMB_SYNC			(1 << 6)
+#define ISI_CFG1_CRC_SYNC			(1 << 7)
+/* Constants for FRATE(ISI_V2) */
+#define		ISI_CFG1_FRATE_CAPTURE_ALL	(0 << 8)
+#define		ISI_CFG1_FRATE_DIV_2		(1 << 8)
+#define		ISI_CFG1_FRATE_DIV_3		(2 << 8)
+#define		ISI_CFG1_FRATE_DIV_4		(3 << 8)
+#define		ISI_CFG1_FRATE_DIV_5		(4 << 8)
+#define		ISI_CFG1_FRATE_DIV_6		(5 << 8)
+#define		ISI_CFG1_FRATE_DIV_7		(6 << 8)
+#define		ISI_CFG1_FRATE_DIV_8		(7 << 8)
+#define ISI_CFG1_DISCR				(1 << 11)
+#define ISI_CFG1_FULL_MODE			(1 << 12)
+
+/* Bitfields in CFG2 */
+#define ISI_CFG2_GRAYSCALE			(1 << 13)
+/* Constants for YCC_SWAP(ISI_V2) */
+#define		ISI_CFG2_YCC_SWAP_DEFAULT	(0 << 28)
+#define		ISI_CFG2_YCC_SWAP_MODE_1	(1 << 28)
+#define		ISI_CFG2_YCC_SWAP_MODE_2	(2 << 28)
+#define		ISI_CFG2_YCC_SWAP_MODE_3	(3 << 28)
+#define ISI_CFG2_IM_VSIZE_OFFSET		0
+#define ISI_CFG2_IM_HSIZE_OFFSET		16
+#define ISI_CFG2_IM_VSIZE_MASK		(0x7FF << ISI_CFG2_IM_VSIZE_OFFSET)
+#define ISI_CFG2_IM_HSIZE_MASK		(0x7FF << ISI_CFG2_IM_HSIZE_OFFSET)
+
+/* Bitfields in CTRL */
+/* Also using in SR(ISI_V2) */
+#define ISI_CTRL_EN				(1 << 0)
+#define ISI_CTRL_CDC				(1 << 8)
+/* Also using in SR/IER/IDR/IMR(ISI_V2) */
+#define ISI_CTRL_DIS				(1 << 1)
+#define ISI_CTRL_SRST				(1 << 2)
+
+/* Bitfields in SR */
+#define ISI_SR_SIP				(1 << 19)
+/* Also using in SR/IER/IDR/IMR */
+#define ISI_SR_VSYNC				(1 << 10)
+#define ISI_SR_PXFR_DONE			(1 << 16)
+#define ISI_SR_CXFR_DONE			(1 << 17)
+#define ISI_SR_P_OVR				(1 << 24)
+#define ISI_SR_C_OVR				(1 << 25)
+#define ISI_SR_CRC_ERR				(1 << 26)
+#define ISI_SR_FR_OVR				(1 << 27)
+
+/* Bitfields in DMA_C_CTRL & in DMA_P_CTRL */
+#define ISI_DMA_CTRL_FETCH			(1 << 0)
+#define ISI_DMA_CTRL_WB				(1 << 1)
+#define ISI_DMA_CTRL_IEN			(1 << 2)
+#define ISI_DMA_CTRL_DONE			(1 << 3)
+
+/* Bitfields in DMA_CHSR/CHER/CHDR */
+#define ISI_DMA_CHSR_P_CH			(1 << 0)
+#define ISI_DMA_CHSR_C_CH			(1 << 1)
+
+/* Definition for isi_platform_data */
+#define ISI_DATAWIDTH_8				0x01
+#define ISI_DATAWIDTH_10			0x02
+
+struct isi_platform_data {
+	u8 has_emb_sync;
+	u8 emb_crc_sync;
+	u8 hsync_act_low;
+	u8 vsync_act_low;
+	u8 pclk_act_falling;
+	u8 isi_full_mode;
+	u32 data_width_flags;
+	/* Using for ISI_CFG1 */
+	u32 frate;
+};
+
+#endif /* __ATMEL_ISI_H__ */