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path: root/drivers/media/common/saa7146_fops.c
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <media/saa7146_vv.h>
#include <linux/module.h>

/****************************************************************************/
/* resource management functions, shamelessly stolen from saa7134 driver */

int saa7146_res_get(struct saa7146_fh *fh, unsigned int bit)
{
	struct saa7146_dev *dev = fh->dev;
	struct saa7146_vv *vv = dev->vv_data;

	if (fh->resources & bit) {
		DEB_D("already allocated! want: 0x%02x, cur:0x%02x\n",
		      bit, vv->resources);
		/* have it already allocated */
		return 1;
	}

	/* is it free? */
	if (vv->resources & bit) {
		DEB_D("locked! vv->resources:0x%02x, we want:0x%02x\n",
		      vv->resources, bit);
		/* no, someone else uses it */
		return 0;
	}
	/* it's free, grab it */
	fh->resources |= bit;
	vv->resources |= bit;
	DEB_D("res: get 0x%02x, cur:0x%02x\n", bit, vv->resources);
	return 1;
}

void saa7146_res_free(struct saa7146_fh *fh, unsigned int bits)
{
	struct saa7146_dev *dev = fh->dev;
	struct saa7146_vv *vv = dev->vv_data;

	BUG_ON((fh->resources & bits) != bits);

	fh->resources &= ~bits;
	vv->resources &= ~bits;
	DEB_D("res: put 0x%02x, cur:0x%02x\n", bits, vv->resources);
}


/********************************************************************************/
/* common dma functions */

void saa7146_dma_free(struct saa7146_dev *dev,struct videobuf_queue *q,
						struct saa7146_buf *buf)
{
	struct videobuf_dmabuf *dma=videobuf_to_dma(&buf->vb);
	DEB_EE("dev:%p, buf:%p\n", dev, buf);

	BUG_ON(in_interrupt());

	videobuf_waiton(q, &buf->vb, 0, 0);
	videobuf_dma_unmap(q->dev, dma);
	videobuf_dma_free(dma);
	buf->vb.state = VIDEOBUF_NEEDS_INIT;
}


/********************************************************************************/
/* common buffer functions */

int saa7146_buffer_queue(struct saa7146_dev *dev,
			 struct saa7146_dmaqueue *q,
			 struct saa7146_buf *buf)
{
	assert_spin_locked(&dev->slock);
	DEB_EE("dev:%p, dmaq:%p, buf:%p\n", dev, q, buf);

	BUG_ON(!q);

	if (NULL == q->curr) {
		q->curr = buf;
		DEB_D("immediately activating buffer %p\n", buf);
		buf->activate(dev,buf,NULL);
	} else {
		list_add_tail(&buf->vb.queue,&q->queue);
		buf->vb.state = VIDEOBUF_QUEUED;
		DEB_D("adding buffer %p to queue. (active buffer present)\n",
		      buf);
	}
	return 0;
}

void saa7146_buffer_finish(struct saa7146_dev *dev,
			   struct saa7146_dmaqueue *q,
			   int state)
{
	assert_spin_locked(&dev->slock);
	DEB_EE("dev:%p, dmaq:%p, state:%d\n", dev, q, state);
	DEB_EE("q->curr:%p\n", q->curr);

	BUG_ON(!q->curr);

	/* finish current buffer */
	if (NULL == q->curr) {
		DEB_D("aiii. no current buffer\n");
		return;
	}

	q->curr->vb.state = state;
	do_gettimeofday(&q->curr->vb.ts);
	wake_up(&q->curr->vb.done);

	q->curr = NULL;
}

void saa7146_buffer_next(struct saa7146_dev *dev,
			 struct saa7146_dmaqueue *q, int vbi)
{
	struct saa7146_buf *buf,*next = NULL;

	BUG_ON(!q);

	DEB_INT("dev:%p, dmaq:%p, vbi:%d\n", dev, q, vbi);

	assert_spin_locked(&dev->slock);
	if (!list_empty(&q->queue)) {
		/* activate next one from queue */
		buf = list_entry(q->queue.next,struct saa7146_buf,vb.queue);
		list_del(&buf->vb.queue);
		if (!list_empty(&q->queue))
			next = list_entry(q->queue.next,struct saa7146_buf, vb.queue);
		q->curr = buf;
		DEB_INT("next buffer: buf:%p, prev:%p, next:%p\n",
			buf, q->queue.prev, q->queue.next);
		buf->activate(dev,buf,next);
	} else {
		DEB_INT("no next buffer. stopping.\n");
		if( 0 != vbi ) {
			/* turn off video-dma3 */
			saa7146_write(dev,MC1, MASK_20);
		} else {
			/* nothing to do -- just prevent next video-dma1 transfer
			   by lowering the protection address */

			// fixme: fix this for vflip != 0

			saa7146_write(dev, PROT_ADDR1, 0);
			saa7146_write(dev, MC2, (MASK_02|MASK_18));

			/* write the address of the rps-program */
			saa7146_write(dev, RPS_ADDR0, dev->d_rps0.dma_handle);
			/* turn on rps */
			saa7146_write(dev, MC1, (MASK_12 | MASK_28));

/*
			printk("vdma%d.base_even:     0x%08x\n", 1,saa7146_read(dev,BASE_EVEN1));
			printk("vdma%d.base_odd:      0x%08x\n", 1,saa7146_read(dev,BASE_ODD1));
			printk("vdma%d.prot_addr:     0x%08x\n", 1,saa7146_read(dev,PROT_ADDR1));
			printk("vdma%d.base_page:     0x%08x\n", 1,saa7146_read(dev,BASE_PAGE1));
			printk("vdma%d.pitch:         0x%08x\n", 1,saa7146_read(dev,PITCH1));
			printk("vdma%d.num_line_byte: 0x%08x\n", 1,saa7146_read(dev,NUM_LINE_BYTE1));
*/
		}
		del_timer(&q->timeout);
	}
}

void saa7146_buffer_timeout(unsigned long data)
{
	struct saa7146_dmaqueue *q = (struct saa7146_dmaqueue*)data;
	struct saa7146_dev *dev = q->dev;
	unsigned long flags;

	DEB_EE("dev:%p, dmaq:%p\n", dev, q);

	spin_lock_irqsave(&dev->slock,flags);
	if (q->curr) {
		DEB_D("timeout on %p\n", q->curr);
		saa7146_buffer_finish(dev,q,VIDEOBUF_ERROR);
	}

	/* we don't restart the transfer here like other drivers do. when
	   a streaming capture is disabled, the timeout function will be
	   called for the current buffer. if we activate the next buffer now,
	   we mess up our capture logic. if a timeout occurs on another buffer,
	   then something is seriously broken before, so no need to buffer the
	   next capture IMHO... */
/*
	saa7146_buffer_next(dev,q);
*/
	spin_unlock_irqrestore(&dev->slock,flags);
}

/********************************************************************************/
/* file operations */

static int fops_open(struct file *file)
{
	struct video_device *vdev = video_devdata(file);
	struct saa7146_dev *dev = video_drvdata(file);
	struct saa7146_fh *fh = NULL;
	int result = 0;

	DEB_EE("file:%p, dev:%s\n", file, video_device_node_name(vdev));

	if (mutex_lock_interruptible(&saa7146_devices_lock))
		return -ERESTARTSYS;

	DEB_D("using: %p\n", dev);

	/* check if an extension is registered */
	if( NULL == dev->ext ) {
		DEB_S("no extension registered for this device\n");
		result = -ENODEV;
		goto out;
	}

	/* allocate per open data */
	fh = kzalloc(sizeof(*fh),GFP_KERNEL);
	if (NULL == fh) {
		DEB_S("cannot allocate memory for per open data\n");
		result = -ENOMEM;
		goto out;
	}

	v4l2_fh_init(&fh->fh, vdev);

	file->private_data = &fh->fh;
	fh->dev = dev;

	if (vdev->vfl_type == VFL_TYPE_VBI) {
		DEB_S("initializing vbi...\n");
		if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
			result = saa7146_vbi_uops.open(dev,file);
		if (dev->ext_vv_data->vbi_fops.open)
			dev->ext_vv_data->vbi_fops.open(file);
	} else {
		DEB_S("initializing video...\n");
		result = saa7146_video_uops.open(dev,file);
	}

	if (0 != result) {
		goto out;
	}

	if( 0 == try_module_get(dev->ext->module)) {
		result = -EINVAL;
		goto out;
	}

	result = 0;
	v4l2_fh_add(&fh->fh);
out:
	if (fh && result != 0) {
		kfree(fh);
		file->private_data = NULL;
	}
	mutex_unlock(&saa7146_devices_lock);
	return result;
}

static int fops_release(struct file *file)
{
	struct video_device *vdev = video_devdata(file);
	struct saa7146_fh  *fh  = file->private_data;
	struct saa7146_dev *dev = fh->dev;

	DEB_EE("file:%p\n", file);

	if (mutex_lock_interruptible(&saa7146_devices_lock))
		return -ERESTARTSYS;

	if (vdev->vfl_type == VFL_TYPE_VBI) {
		if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
			saa7146_vbi_uops.release(dev,file);
		if (dev->ext_vv_data->vbi_fops.release)
			dev->ext_vv_data->vbi_fops.release(file);
	} else {
		saa7146_video_uops.release(dev,file);
	}

	v4l2_fh_del(&fh->fh);
	v4l2_fh_exit(&fh->fh);
	module_put(dev->ext->module);
	file->private_data = NULL;
	kfree(fh);

	mutex_unlock(&saa7146_devices_lock);

	return 0;
}

static int fops_mmap(struct file *file, struct vm_area_struct * vma)
{
	struct video_device *vdev = video_devdata(file);
	struct saa7146_fh *fh = file->private_data;
	struct videobuf_queue *q;

	switch (vdev->vfl_type) {
	case VFL_TYPE_GRABBER: {
		DEB_EE("V4L2_BUF_TYPE_VIDEO_CAPTURE: file:%p, vma:%p\n",
		       file, vma);
		q = &fh->video_q;
		break;
		}
	case VFL_TYPE_VBI: {
		DEB_EE("V4L2_BUF_TYPE_VBI_CAPTURE: file:%p, vma:%p\n",
		       file, vma);
		if (fh->dev->ext_vv_data->capabilities & V4L2_CAP_SLICED_VBI_OUTPUT)
			return -ENODEV;
		q = &fh->vbi_q;
		break;
		}
	default:
		BUG();
		return 0;
	}

	return videobuf_mmap_mapper(q,vma);
}

static unsigned int fops_poll(struct file *file, struct poll_table_struct *wait)
{
	struct video_device *vdev = video_devdata(file);
	struct saa7146_fh *fh = file->private_data;
	struct videobuf_buffer *buf = NULL;
	struct videobuf_queue *q;
	unsigned int res = v4l2_ctrl_poll(file, wait);

	DEB_EE("file:%p, poll:%p\n", file, wait);

	if (vdev->vfl_type == VFL_TYPE_VBI) {
		if (fh->dev->ext_vv_data->capabilities & V4L2_CAP_SLICED_VBI_OUTPUT)
			return res | POLLOUT | POLLWRNORM;
		if( 0 == fh->vbi_q.streaming )
			return res | videobuf_poll_stream(file, &fh->vbi_q, wait);
		q = &fh->vbi_q;
	} else {
		DEB_D("using video queue\n");
		q = &fh->video_q;
	}

	if (!list_empty(&q->stream))
		buf = list_entry(q->stream.next, struct videobuf_buffer, stream);

	if (!buf) {
		DEB_D("buf == NULL!\n");
		return res | POLLERR;
	}

	poll_wait(file, &buf->done, wait);
	if (buf->state == VIDEOBUF_DONE || buf->state == VIDEOBUF_ERROR) {
		DEB_D("poll succeeded!\n");
		return res | POLLIN | POLLRDNORM;
	}

	DEB_D("nothing to poll for, buf->state:%d\n", buf->state);
	return res;
}

static ssize_t fops_read(struct file *file, char __user *data, size_t count, loff_t *ppos)
{
	struct video_device *vdev = video_devdata(file);
	struct saa7146_fh *fh = file->private_data;

	switch (vdev->vfl_type) {
	case VFL_TYPE_GRABBER:
/*
		DEB_EE("V4L2_BUF_TYPE_VIDEO_CAPTURE: file:%p, data:%p, count:%lun",
		       file, data, (unsigned long)count);
*/
		return saa7146_video_uops.read(file,data,count,ppos);
	case VFL_TYPE_VBI:
/*
		DEB_EE("V4L2_BUF_TYPE_VBI_CAPTURE: file:%p, data:%p, count:%lu\n",
		       file, data, (unsigned long)count);
*/
		if (fh->dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
			return saa7146_vbi_uops.read(file,data,count,ppos);
		return -EINVAL;
	default:
		BUG();
		return 0;
	}
}

static ssize_t fops_write(struct file *file, const char __user *data, size_t count, loff_t *ppos)
{
	struct video_device *vdev = video_devdata(file);
	struct saa7146_fh *fh = file->private_data;

	switch (vdev->vfl_type) {
	case VFL_TYPE_GRABBER:
		return -EINVAL;
	case VFL_TYPE_VBI:
		if (fh->dev->ext_vv_data->vbi_fops.write)
			return fh->dev->ext_vv_data->vbi_fops.write(file, data, count, ppos);
		else
			return -EINVAL;
	default:
		BUG();
		return -EINVAL;
	}
}

static const struct v4l2_file_operations video_fops =
{
	.owner		= THIS_MODULE,
	.open		= fops_open,
	.release	= fops_release,
	.read		= fops_read,
	.write		= fops_write,
	.poll		= fops_poll,
	.mmap		= fops_mmap,
	.unlocked_ioctl	= video_ioctl2,
};

static void vv_callback(struct saa7146_dev *dev, unsigned long status)
{
	u32 isr = status;

	DEB_INT("dev:%p, isr:0x%08x\n", dev, (u32)status);

	if (0 != (isr & (MASK_27))) {
		DEB_INT("irq: RPS0 (0x%08x)\n", isr);
		saa7146_video_uops.irq_done(dev,isr);
	}

	if (0 != (isr & (MASK_28))) {
		u32 mc2 = saa7146_read(dev, MC2);
		if( 0 != (mc2 & MASK_15)) {
			DEB_INT("irq: RPS1 vbi workaround (0x%08x)\n", isr);
			wake_up(&dev->vv_data->vbi_wq);
			saa7146_write(dev,MC2, MASK_31);
			return;
		}
		DEB_INT("irq: RPS1 (0x%08x)\n", isr);
		saa7146_vbi_uops.irq_done(dev,isr);
	}
}

static const struct v4l2_ctrl_ops saa7146_ctrl_ops = {
	.s_ctrl = saa7146_s_ctrl,
};

int saa7146_vv_init(struct saa7146_dev* dev, struct saa7146_ext_vv *ext_vv)
{
	struct v4l2_ctrl_handler *hdl = &dev->ctrl_handler;
	struct v4l2_pix_format *fmt;
	struct v4l2_vbi_format *vbi;
	struct saa7146_vv *vv;
	int err;

	err = v4l2_device_register(&dev->pci->dev, &dev->v4l2_dev);
	if (err)
		return err;

	v4l2_ctrl_handler_init(hdl, 6);
	v4l2_ctrl_new_std(hdl, &saa7146_ctrl_ops,
		V4L2_CID_BRIGHTNESS, 0, 255, 1, 128);
	v4l2_ctrl_new_std(hdl, &saa7146_ctrl_ops,
		V4L2_CID_CONTRAST, 0, 127, 1, 64);
	v4l2_ctrl_new_std(hdl, &saa7146_ctrl_ops,
		V4L2_CID_SATURATION, 0, 127, 1, 64);
	v4l2_ctrl_new_std(hdl, &saa7146_ctrl_ops,
		V4L2_CID_VFLIP, 0, 1, 1, 0);
	v4l2_ctrl_new_std(hdl, &saa7146_ctrl_ops,
		V4L2_CID_HFLIP, 0, 1, 1, 0);
	if (hdl->error) {
		err = hdl->error;
		v4l2_ctrl_handler_free(hdl);
		return err;
	}
	dev->v4l2_dev.ctrl_handler = hdl;

	vv = kzalloc(sizeof(struct saa7146_vv), GFP_KERNEL);
	if (vv == NULL) {
		ERR("out of memory. aborting.\n");
		v4l2_ctrl_handler_free(hdl);
		return -ENOMEM;
	}
	ext_vv->vid_ops = saa7146_video_ioctl_ops;
	ext_vv->vbi_ops = saa7146_vbi_ioctl_ops;
	ext_vv->core_ops = &saa7146_video_ioctl_ops;

	DEB_EE("dev:%p\n", dev);

	/* set default values for video parts of the saa7146 */
	saa7146_write(dev, BCS_CTRL, 0x80400040);

	/* enable video-port pins */
	saa7146_write(dev, MC1, (MASK_10 | MASK_26));

	/* save per-device extension data (one extension can
	   handle different devices that might need different
	   configuration data) */
	dev->ext_vv_data = ext_vv;

	vv->d_clipping.cpu_addr = pci_alloc_consistent(dev->pci, SAA7146_CLIPPING_MEM, &vv->d_clipping.dma_handle);
	if( NULL == vv->d_clipping.cpu_addr ) {
		ERR("out of memory. aborting.\n");
		kfree(vv);
		v4l2_ctrl_handler_free(hdl);
		return -1;
	}
	memset(vv->d_clipping.cpu_addr, 0x0, SAA7146_CLIPPING_MEM);

	saa7146_video_uops.init(dev,vv);
	if (dev->ext_vv_data->capabilities & V4L2_CAP_VBI_CAPTURE)
		saa7146_vbi_uops.init(dev,vv);

	fmt = &vv->ov_fb.fmt;
	fmt->width = vv->standard->h_max_out;
	fmt->height = vv->standard->v_max_out;
	fmt->pixelformat = V4L2_PIX_FMT_RGB565;
	fmt->bytesperline = 2 * fmt->width;
	fmt->sizeimage = fmt->bytesperline * fmt->height;
	fmt->colorspace = V4L2_COLORSPACE_SRGB;

	fmt = &vv->video_fmt;
	fmt->width = 384;
	fmt->height = 288;
	fmt->pixelformat = V4L2_PIX_FMT_BGR24;
	fmt->field = V4L2_FIELD_ANY;
	fmt->colorspace = V4L2_COLORSPACE_SMPTE170M;
	fmt->bytesperline = 3 * fmt->width;
	fmt->sizeimage = fmt->bytesperline * fmt->height;

	vbi = &vv->vbi_fmt;
	vbi->sampling_rate	= 27000000;
	vbi->offset		= 248; /* todo */
	vbi->samples_per_line	= 720 * 2;
	vbi->sample_format	= V4L2_PIX_FMT_GREY;

	/* fixme: this only works for PAL */
	vbi->start[0] = 5;
	vbi->count[0] = 16;
	vbi->start[1] = 312;
	vbi->count[1] = 16;

	init_timer(&vv->vbi_read_timeout);

	vv->ov_fb.capability = V4L2_FBUF_CAP_LIST_CLIPPING;
	vv->ov_fb.flags = V4L2_FBUF_FLAG_PRIMARY;
	dev->vv_data = vv;
	dev->vv_callback = &vv_callback;

	return 0;
}
EXPORT_SYMBOL_GPL(saa7146_vv_init);

int saa7146_vv_release(struct saa7146_dev* dev)
{
	struct saa7146_vv *vv = dev->vv_data;

	DEB_EE("dev:%p\n", dev);

	v4l2_device_unregister(&dev->v4l2_dev);
	pci_free_consistent(dev->pci, SAA7146_CLIPPING_MEM, vv->d_clipping.cpu_addr, vv->d_clipping.dma_handle);
	v4l2_ctrl_handler_free(&dev->ctrl_handler);
	kfree(vv);
	dev->vv_data = NULL;
	dev->vv_callback = NULL;

	return 0;
}
EXPORT_SYMBOL_GPL(saa7146_vv_release);

int saa7146_register_device(struct video_device **vid, struct saa7146_dev* dev,
			    char *name, int type)
{
	struct video_device *vfd;
	int err;
	int i;

	DEB_EE("dev:%p, name:'%s', type:%d\n", dev, name, type);

	// released by vfd->release
	vfd = video_device_alloc();
	if (vfd == NULL)
		return -ENOMEM;

	vfd->fops = &video_fops;
	if (type == VFL_TYPE_GRABBER)
		vfd->ioctl_ops = &dev->ext_vv_data->vid_ops;
	else
		vfd->ioctl_ops = &dev->ext_vv_data->vbi_ops;
	vfd->release = video_device_release;
	/* Locking in file operations other than ioctl should be done by
	   the driver, not the V4L2 core.
	   This driver needs auditing so that this flag can be removed. */
	set_bit(V4L2_FL_LOCK_ALL_FOPS, &vfd->flags);
	vfd->lock = &dev->v4l2_lock;
	vfd->v4l2_dev = &dev->v4l2_dev;
	vfd->tvnorms = 0;
	set_bit(V4L2_FL_USE_FH_PRIO, &vfd->flags);
	for (i = 0; i < dev->ext_vv_data->num_stds; i++)
		vfd->tvnorms |= dev->ext_vv_data->stds[i].id;
	strlcpy(vfd->name, name, sizeof(vfd->name));
	video_set_drvdata(vfd, dev);

	err = video_register_device(vfd, type, -1);
	if (err < 0) {
		ERR("cannot register v4l2 device. skipping.\n");
		video_device_release(vfd);
		return err;
	}

	pr_info("%s: registered device %s [v4l2]\n",
		dev->name, video_device_node_name(vfd));

	*vid = vfd;
	return 0;
}
EXPORT_SYMBOL_GPL(saa7146_register_device);

int saa7146_unregister_device(struct video_device **vid, struct saa7146_dev* dev)
{
	DEB_EE("dev:%p\n", dev);

	video_unregister_device(*vid);
	*vid = NULL;

	return 0;
}
EXPORT_SYMBOL_GPL(saa7146_unregister_device);

static int __init saa7146_vv_init_module(void)
{
	return 0;
}


static void __exit saa7146_vv_cleanup_module(void)
{
}

module_init(saa7146_vv_init_module);
module_exit(saa7146_vv_cleanup_module);

MODULE_AUTHOR("Michael Hunold <michael@mihu.de>");
MODULE_DESCRIPTION("video4linux driver for saa7146-based hardware");
MODULE_LICENSE("GPL");