gspca.c

trident tm5600的linux驱动

	PDEBUG(D_FRAM, "qbuf %d", v4l2_buf->index);
	if (v4l2_buf->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return -EINVAL;

	if (mutex_lock_interruptible(&gspca_dev->queue_lock))
		return -ERESTARTSYS;

	index = v4l2_buf->index;
	if ((unsigned) index >= gspca_dev->nframes) {
		PDEBUG(D_FRAM,
			"qbuf idx %d >= %d", index, gspca_dev->nframes);
		ret = -EINVAL;
		goto out;
	}
	if (v4l2_buf->memory != gspca_dev->memory) {
		PDEBUG(D_FRAM, "qbuf bad memory type");
		ret = -EINVAL;
		goto out;
	}

	frame = &gspca_dev->frame[index];
	if (frame->v4l2_buf.flags & BUF_ALL_FLAGS) {
		PDEBUG(D_FRAM, "qbuf bad state");
		ret = -EINVAL;
		goto out;
	}

	frame->v4l2_buf.flags |= V4L2_BUF_FLAG_QUEUED;

	if (frame->v4l2_buf.memory == V4L2_MEMORY_USERPTR) {
		frame->v4l2_buf.m.userptr = v4l2_buf->m.userptr;
		frame->v4l2_buf.length = v4l2_buf->length;
	}

	/* put the buffer in the 'queued' queue */
	i = gspca_dev->fr_q;
	gspca_dev->fr_queue[i] = index;
	gspca_dev->fr_q = (i + 1) % gspca_dev->nframes;
	PDEBUG(D_FRAM, "qbuf q:%d i:%d o:%d",
		gspca_dev->fr_q,
		gspca_dev->fr_i,
		gspca_dev->fr_o);

	v4l2_buf->flags |= V4L2_BUF_FLAG_QUEUED;
	v4l2_buf->flags &= ~V4L2_BUF_FLAG_DONE;
	ret = 0;
out:
	mutex_unlock(&gspca_dev->queue_lock);
	return ret;
}

/*
 * allocate the resources for read()
 */
static int read_alloc(struct gspca_dev *gspca_dev,
			struct file *file)
{
	struct v4l2_buffer v4l2_buf;
	int i, ret;

	PDEBUG(D_STREAM, "read alloc");
	if (gspca_dev->nframes == 0) {
		struct v4l2_requestbuffers rb;

		memset(&rb, 0, sizeof rb);
		rb.count = gspca_dev->nbufread;
		rb.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		rb.memory = GSPCA_MEMORY_READ;
		ret = vidioc_reqbufs(file, gspca_dev, &rb);
		if (ret != 0) {
			PDEBUG(D_STREAM, "read reqbuf err %d", ret);
			return ret;
		}
		memset(&v4l2_buf, 0, sizeof v4l2_buf);
		v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		v4l2_buf.memory = GSPCA_MEMORY_READ;
		for (i = 0; i < gspca_dev->nbufread; i++) {
			v4l2_buf.index = i;
			ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
			if (ret != 0) {
				PDEBUG(D_STREAM, "read qbuf err: %d", ret);
				return ret;
			}
		}
		gspca_dev->memory = GSPCA_MEMORY_READ;
	}

	/* start streaming */
	ret = vidioc_streamon(file, gspca_dev, V4L2_BUF_TYPE_VIDEO_CAPTURE);
	if (ret != 0)
		PDEBUG(D_STREAM, "read streamon err %d", ret);
	return ret;
}

static unsigned int dev_poll(struct file *file, poll_table *wait)
{
	struct gspca_dev *gspca_dev = file->private_data;
	int i, ret;

	PDEBUG(D_FRAM, "poll");

	poll_wait(file, &gspca_dev->wq, wait);
	if (!gspca_dev->present)
		return POLLERR;

	/* if reqbufs is not done, the user would use read() */
	if (gspca_dev->nframes == 0) {
		if (gspca_dev->memory != GSPCA_MEMORY_NO)
			return POLLERR;		/* not the 1st time */
		ret = read_alloc(gspca_dev, file);
		if (ret != 0)
			return POLLERR;
	}

	if (mutex_lock_interruptible(&gspca_dev->queue_lock) != 0)
		return POLLERR;
	if (!gspca_dev->present) {
		ret = POLLERR;
		goto out;
	}

	/* check the next incoming buffer */
	i = gspca_dev->fr_o;
	i = gspca_dev->fr_queue[i];
	if (gspca_dev->frame[i].v4l2_buf.flags & V4L2_BUF_FLAG_DONE)
		ret = POLLIN | POLLRDNORM;	/* something to read */
	else
		ret = 0;
out:
	mutex_unlock(&gspca_dev->queue_lock);
	return ret;
}

static ssize_t dev_read(struct file *file, char __user *data,
		    size_t count, loff_t *ppos)
{
	struct gspca_dev *gspca_dev = file->private_data;
	struct gspca_frame *frame;
	struct v4l2_buffer v4l2_buf;
	struct timeval timestamp;
	int n, ret, ret2;

	PDEBUG(D_FRAM, "read (%zd)", count);
	if (!gspca_dev->present)
		return -ENODEV;
	switch (gspca_dev->memory) {
	case GSPCA_MEMORY_NO:			/* first time */
		ret = read_alloc(gspca_dev, file);
		if (ret != 0)
			return ret;
		break;
	case GSPCA_MEMORY_READ:
		if (gspca_dev->capt_file == file)
			break;
		/* fall thru */
	default:
		return -EINVAL;
	}

	/* get a frame */
	jiffies_to_timeval(get_jiffies_64(), &timestamp);
	timestamp.tv_sec--;
	n = 2;
	for (;;) {
		memset(&v4l2_buf, 0, sizeof v4l2_buf);
		v4l2_buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		v4l2_buf.memory = GSPCA_MEMORY_READ;
		ret = vidioc_dqbuf(file, gspca_dev, &v4l2_buf);
		if (ret != 0) {
			PDEBUG(D_STREAM, "read dqbuf err %d", ret);
			return ret;
		}

		/* if the process slept for more than 1 second,
		 * get a newer frame */
		frame = &gspca_dev->frame[v4l2_buf.index];
		if (--n < 0)
			break;			/* avoid infinite loop */
		if (frame->v4l2_buf.timestamp.tv_sec >= timestamp.tv_sec)
			break;
		ret = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
		if (ret != 0) {
			PDEBUG(D_STREAM, "read qbuf err %d", ret);
			return ret;
		}
	}

	/* copy the frame */
	if (count > frame->v4l2_buf.bytesused)
		count = frame->v4l2_buf.bytesused;
	ret = copy_to_user(data, frame->data, count);
	if (ret != 0) {
		PDEBUG(D_ERR|D_STREAM,
			"read cp to user lack %d / %zd", ret, count);
		ret = -EFAULT;
		goto out;
	}
	ret = count;
out:
	/* in each case, requeue the buffer */
	ret2 = vidioc_qbuf(file, gspca_dev, &v4l2_buf);
	if (ret2 != 0)
		return ret2;
	return ret;
}

static void dev_release(struct video_device *vfd)
{
	/* nothing */
}

static struct file_operations dev_fops = {
	.owner = THIS_MODULE,
	.open = dev_open,
	.release = dev_close,
	.read = dev_read,
	.mmap = dev_mmap,
	.ioctl = video_ioctl2,
#ifdef CONFIG_COMPAT
	.compat_ioctl = v4l_compat_ioctl32,
#endif
	.llseek = no_llseek,
	.poll	= dev_poll,
};

static const struct v4l2_ioctl_ops dev_ioctl_ops = {
	.vidioc_querycap	= vidioc_querycap,
	.vidioc_dqbuf		= vidioc_dqbuf,
	.vidioc_qbuf		= vidioc_qbuf,
	.vidioc_enum_fmt_vid_cap = vidioc_enum_fmt_vid_cap,
	.vidioc_try_fmt_vid_cap	= vidioc_try_fmt_vid_cap,
	.vidioc_g_fmt_vid_cap	= vidioc_g_fmt_vid_cap,
	.vidioc_s_fmt_vid_cap	= vidioc_s_fmt_vid_cap,
	.vidioc_streamon	= vidioc_streamon,
	.vidioc_queryctrl	= vidioc_queryctrl,
	.vidioc_g_ctrl		= vidioc_g_ctrl,
	.vidioc_s_ctrl		= vidioc_s_ctrl,
	.vidioc_querymenu	= vidioc_querymenu,
	.vidioc_enum_input	= vidioc_enum_input,
	.vidioc_g_input		= vidioc_g_input,
	.vidioc_s_input		= vidioc_s_input,
	.vidioc_reqbufs		= vidioc_reqbufs,
	.vidioc_querybuf	= vidioc_querybuf,
	.vidioc_streamoff	= vidioc_streamoff,
	.vidioc_g_jpegcomp	= vidioc_g_jpegcomp,
	.vidioc_s_jpegcomp	= vidioc_s_jpegcomp,
	.vidioc_g_parm		= vidioc_g_parm,
	.vidioc_s_parm		= vidioc_s_parm,
	.vidioc_s_std		= vidioc_s_std,
#ifdef CONFIG_VIDEO_V4L1_COMPAT
	.vidiocgmbuf          = vidiocgmbuf,
#endif
};

static struct video_device gspca_template = {
	.name = "gspca main driver",
	.fops = &dev_fops,
	.ioctl_ops = &dev_ioctl_ops,
	.release = dev_release,		/* mandatory */
	.minor = -1,
};

/*
 * probe and create a new gspca device
 *
 * This function must be called by the sub-driver when it is
 * called for probing a new device.
 */
int gspca_dev_probe(struct usb_interface *intf,
		const struct usb_device_id *id,
		const struct sd_desc *sd_desc,
		int dev_size,
		struct module *module)
{
	struct usb_interface_descriptor *interface;
	struct gspca_dev *gspca_dev;
	struct usb_device *dev = interface_to_usbdev(intf);
	int ret;

	PDEBUG(D_PROBE, "probing %04x:%04x", id->idVendor, id->idProduct);

	/* we don't handle multi-config cameras */
	if (dev->descriptor.bNumConfigurations != 1)
		return -ENODEV;
	interface = &intf->cur_altsetting->desc;
	if (interface->bInterfaceNumber > 0)
		return -ENODEV;

	/* create the device */
	if (dev_size < sizeof *gspca_dev)
		dev_size = sizeof *gspca_dev;
	gspca_dev = kzalloc(dev_size, GFP_KERNEL);
	if (!gspca_dev) {
		err("couldn't kzalloc gspca struct");
		return -ENOMEM;
	}
	kref_init(&gspca_dev->kref);
	gspca_dev->usb_buf = kmalloc(USB_BUF_SZ, GFP_KERNEL);
	if (!gspca_dev->usb_buf) {
		err("out of memory");
		ret = -ENOMEM;
		goto out;
	}
	gspca_dev->dev = dev;
	gspca_dev->iface = interface->bInterfaceNumber;
	gspca_dev->nbalt = intf->num_altsetting;
	gspca_dev->sd_desc = sd_desc;
	gspca_dev->nbufread = 2;

	/* configure the subdriver and initialize the USB device */
	ret = gspca_dev->sd_desc->config(gspca_dev, id);
	if (ret < 0)
		goto out;
	ret = gspca_dev->sd_desc->init(gspca_dev);
	if (ret < 0)
		goto out;
	ret = gspca_set_alt0(gspca_dev);
	if (ret < 0)
		goto out;
	gspca_set_default_mode(gspca_dev);

	mutex_init(&gspca_dev->usb_lock);
	mutex_init(&gspca_dev->read_lock);
	mutex_init(&gspca_dev->queue_lock);
	init_waitqueue_head(&gspca_dev->wq);

	/* init video stuff */
	memcpy(&gspca_dev->vdev, &gspca_template, sizeof gspca_template);
	gspca_dev->vdev.parent = &dev->dev;
	memcpy(&gspca_dev->fops, &dev_fops, sizeof gspca_dev->fops);
	gspca_dev->vdev.fops = &gspca_dev->fops;
	gspca_dev->fops.owner = module;		/* module protection */
	gspca_dev->present = 1;
	ret = video_register_device(&gspca_dev->vdev,
				  VFL_TYPE_GRABBER,
				  video_nr);
	if (ret < 0) {
		err("video_register_device err %d", ret);
		goto out;
	}

	usb_set_intfdata(intf, gspca_dev);
	PDEBUG(D_PROBE, "probe ok");
	return 0;
out:
	kref_put(&gspca_dev->kref, gspca_delete);
	return ret;
}
EXPORT_SYMBOL(gspca_dev_probe);

/*
 * USB disconnection
 *
 * This function must be called by the sub-driver
 * when the device disconnects, after the specific resources are freed.
 */
void gspca_disconnect(struct usb_interface *intf)
{
	struct gspca_dev *gspca_dev = usb_get_intfdata(intf);

	usb_set_intfdata(intf, NULL);

/* We don't want people trying to open up the device */
	video_unregister_device(&gspca_dev->vdev);

	gspca_dev->present = 0;
	gspca_dev->streaming = 0;

	kref_put(&gspca_dev->kref, gspca_delete);

	PDEBUG(D_PROBE, "disconnect complete");
}
EXPORT_SYMBOL(gspca_disconnect);

#ifdef CONFIG_PM
int gspca_suspend(struct usb_interface *intf, pm_message_t message)
{
	struct gspca_dev *gspca_dev = usb_get_intfdata(intf);

	if (!gspca_dev->streaming)
		return 0;
	gspca_dev->frozen = 1;		/* avoid urb error messages */
	if (gspca_dev->sd_desc->stopN)
		gspca_dev->sd_desc->stopN(gspca_dev);
	destroy_urbs(gspca_dev);
	gspca_set_alt0(gspca_dev);
	if (gspca_dev->sd_desc->stop0)
		gspca_dev->sd_desc->stop0(gspca_dev);
	return 0;
}
EXPORT_SYMBOL(gspca_suspend);

int gspca_resume(struct usb_interface *intf)
{
	struct gspca_dev *gspca_dev = usb_get_intfdata(intf);

	gspca_dev->frozen = 0;
	gspca_dev->sd_desc->init(gspca_dev);
	if (gspca_dev->streaming)
		return gspca_init_transfer(gspca_dev);
	return 0;
}
EXPORT_SYMBOL(gspca_resume);
#endif
/* -- cam driver utility functions -- */

/* auto gain and exposure algorithm based on the knee algorithm described here:
   http://ytse.tricolour.net/docs/LowLightOptimization.html

   Returns 0 if no changes were made, 1 if the gain and or exposure settings
   where changed. */
int gspca_auto_gain_n_exposure(struct gspca_dev *gspca_dev, int avg_lum,
	int desired_avg_lum, int deadzone, int gain_knee, int exposure_knee)
{
	int i, steps, gain, orig_gain, exposure, orig_exposure, autogain;
	const struct ctrl *gain_ctrl = NULL;
	const struct ctrl *exposure_ctrl = NULL;
	const struct ctrl *autogain_ctrl = NULL;
	int retval = 0;

	for (i = 0; i < gspca_dev->sd_desc->nctrls; i++) {
		if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_GAIN)
			gain_ctrl = &gspca_dev->sd_desc->ctrls[i];
		if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_EXPOSURE)
			exposure_ctrl = &gspca_dev->sd_desc->ctrls[i];
		if (gspca_dev->sd_desc->ctrls[i].qctrl.id == V4L2_CID_AUTOGAIN)
			autogain_ctrl = &gspca_dev->sd_desc->ctrls[i];
	}
	if (!gain_ctrl || !exposure_ctrl || !autogain_ctrl) {
		PDEBUG(D_ERR, "Error: gspca_auto_gain_n_exposure called "
			"on cam without (auto)gain/exposure");
		return 0;
	}

	if (gain_ctrl->get(gspca_dev, &gain) ||
			exposure_ctrl->get(gspca_dev, &exposure) ||
			autogain_ctrl->get(gspca_dev, &autogain) || !autogain)
		return 0;

	orig_gain = gain;
	orig_exposure = exposure;

	/* If we are of a multiple of deadzone, do multiple steps to reach the
	   desired lumination fast (with the risc of a slight overshoot) */
	steps = abs(desired_avg_lum - avg_lum) / deadzone;

	PDEBUG(D_FRAM, "autogain: lum: %d, desired: %d, steps: %d\n",
		avg_lum, desired_avg_lum, steps);

	for (i = 0; i < steps; i++) {
		if (avg_lum > desired_avg_lum) {
			if (gain > gain_knee)
				gain--;
			else if (exposure > exposure_knee)
				exposure--;
			else if (gain > gain_ctrl->qctrl.default_value)
				gain--;
			else if (exposure > exposure_ctrl->qctrl.minimum)
				exposure--;
			else if (gain > gain_ctrl->qctrl.minimum)
				gain--;
			else
				break;
		} else {
			if (gain < gain_ctrl->qctrl.default_value)
				gain++;
			else if (exposure < exposure_knee)
				exposure++;
			else if (gain < gain_knee)
				gain++;
			else if (exposure < exposure_ctrl->qctrl.maximum)
				exposure++;
			else if (gain < gain_ctrl->qctrl.maximum)
				gain++;
			else
				break;
		}
	}

	if (gain != orig_gain) {
		gain_ctrl->set(gspca_dev, gain);
		retval = 1;
	}
	if (exposure != orig_exposure) {
		exposure_ctrl->set(gspca_dev, exposure);
		retval = 1;
	}

	return retval;
}
EXPORT_SYMBOL(gspca_auto_gain_n_exposure);

/* -- module insert / remove -- */
static int __init gspca_init(void)
{
	info("main v%d.%d.%d registered",
		(DRIVER_VERSION_NUMBER >> 16) & 0xff,
		(DRIVER_VERSION_NUMBER >> 8) & 0xff,
		DRIVER_VERSION_NUMBER & 0xff);
	return 0;
}
static void __exit gspca_exit(void)
{
	info("main deregistered");
}

module_init(gspca_init);
module_exit(gspca_exit);

#ifdef GSPCA_DEBUG
module_param_named(debug, gspca_debug, int, 0644);
MODULE_PARM_DESC(debug,
		"Debug (bit) 0x01:error 0x02:probe 0x04:config"
		" 0x08:stream 0x10:frame 0x20:packet 0x40:USBin 0x80:USBout"
		" 0x0100: v4l2");
#endif