pwc-if.c

Linux support for Philips USB webcams halted Latest version: pwc-9.0.2.tar.gz (including documents

	Trace(TRACE_OPEN, ">> pwc_isoc_cleanup()\n");
	if (pdev == NULL)
		return;

	/* Unlinking ISOC buffers one by one */
	for (i = 0; i < MAX_ISO_BUFS; i++) {
		struct urb *urb;

		urb = pdev->sbuf[i].urb;
		if (urb != 0) {
			if (pdev->iso_init) {
				Trace(TRACE_MEMORY, "Unlinking URB %p\n", urb);
				usb_unlink_urb(urb);
			}
			Trace(TRACE_MEMORY, "Freeing URB\n");
			usb_free_urb(urb);
			pdev->sbuf[i].urb = NULL;
		}
	}

	/* Stop camera, but only if we are sure the camera is still there (unplug
	   is signalled by EPIPE) 
	 */
	if (pdev->error_status && pdev->error_status != EPIPE) {
		Trace(TRACE_OPEN, "Setting alternate interface 0.\n");
		usb_set_interface(pdev->udev, 0, 0);
	}

	pdev->iso_init = 0;
	Trace(TRACE_OPEN, "<< pwc_isoc_cleanup()\n");
}

int pwc_try_video_mode(struct pwc_device *pdev, int width, int height, int new_fps, int new_compression, int new_snapshot)
{
	int ret, start;

	/* Stop isoc stuff */
	pwc_isoc_cleanup(pdev);
	/* Reset parameters */
	pwc_reset_buffers(pdev);
	/* Try to set video mode... */
	start = ret = pwc_set_video_mode(pdev, width, height, new_fps, new_compression, new_snapshot);
	if (ret) { 
	        Trace(TRACE_FLOW, "pwc_set_video_mode attempt 1 failed.\n");
		/* That failed... restore old mode (we know that worked) */
		start = pwc_set_video_mode(pdev, pdev->view.x, pdev->view.y, pdev->vframes, pdev->vcompression, pdev->vsnapshot);
		if (start) {
		        Trace(TRACE_FLOW, "pwc_set_video_mode attempt 2 failed.\n");
		}
	}
	if (start == 0)
	{
		if (pwc_isoc_init(pdev) < 0)
		{
			Info("Failed to restart ISOC transfers in pwc_try_video_mode.\n");
			ret = -EAGAIN; /* let's try again, who knows if it works a second time */
		}
	}
	pdev->drop_frames++; /* try to avoid garbage during switch */
	return ret; /* Return original error code */
}


/***************************************************************************/
/* Video4Linux functions */

static int pwc_video_open(struct video_device *vdev, int mode)
{
	int i;
	struct pwc_device *pdev;

	Trace(TRACE_OPEN, ">> video_open called(vdev = 0x%p).\n", vdev);
	
	if (vdev == NULL)
		BUG();
	pdev = (struct pwc_device *)vdev->priv;
	if (pdev == NULL)
		BUG();
	if (pdev->vopen)
		return -EBUSY;
	
	down(&pdev->modlock);
	if (!pdev->usb_init) {
		Trace(TRACE_OPEN, "Doing first time initialization.\n");
		pdev->usb_init = 1;

		if (pwc_trace & TRACE_OPEN)		
		{
			/* Query sensor type */
			const char *sensor_type = NULL;
			int ret;

			ret = pwc_get_cmos_sensor(pdev, &i);
			if (ret >= 0)
			{
				switch(i) {
				case 0x00:  sensor_type = "Hyundai CMOS sensor"; break;
				case 0x20:  sensor_type = "Sony CCD sensor + TDA8787"; break;
				case 0x2E:  sensor_type = "Sony CCD sensor + Exas 98L59"; break;
				case 0x2F:  sensor_type = "Sony CCD sensor + ADI 9804"; break;
				case 0x30:  sensor_type = "Sharp CCD sensor + TDA8787"; break;
				case 0x3E:  sensor_type = "Sharp CCD sensor + Exas 98L59"; break;
				case 0x3F:  sensor_type = "Sharp CCD sensor + ADI 9804"; break;
				case 0x40:  sensor_type = "UPA 1021 sensor"; break;
				case 0x100: sensor_type = "VGA sensor"; break;
				case 0x101: sensor_type = "PAL MR sensor"; break;
				default:    sensor_type = "unknown type of sensor"; break;
				}
			}
			if (sensor_type != NULL)
				Info("This %s camera is equipped with a %s (%d).\n", pdev->vdev->name, sensor_type, i);
		}
	}

	/* Turn on camera */
	if (power_save) {
		i = pwc_camera_power(pdev, 1);
		if (i < 0)
			Info("Failed to restore power to the camera! (%d)\n", i);
	}
	/* Set LED on/off time */
	if (pwc_set_leds(pdev, led_on, led_off) < 0)
		Info("Failed to set LED on/off time.\n");

	/* Find our decompressor, if any */
	pdev->decompressor = pwc_find_decompressor(pdev->type);
#if PWC_DEBUG	
	Debug("Found decompressor for %d at 0x%p\n", pdev->type, pdev->decompressor);
#endif
	pwc_construct(pdev); /* set min/max sizes correct */

	/* So far, so good. Allocate memory. */
	i = pwc_allocate_buffers(pdev);
	if (i < 0) {
		Trace(TRACE_OPEN, "Failed to allocate buffer memory.\n");
		up(&pdev->modlock);
		return i;
	}
	
	/* Reset buffers & parameters */
	pwc_reset_buffers(pdev);
	for (i = 0; i < default_mbufs; i++)
		pdev->image_used[i] = 0;
	pdev->vframe_count = 0;
	pdev->vframes_dumped = 0;
	pdev->vframes_error = 0;
	pdev->visoc_errors = 0;
	pdev->error_status = 0;
#if PWC_DEBUG
	pdev->sequence = 0;
#endif
	pwc_construct(pdev); /* set min/max sizes correct */

	/* Set some defaults */
	pdev->vsnapshot = 0;

	/* Start iso pipe for video; first try the last used video size
	   (or the default one); if that fails try QCIF/10 or QSIF/10;
	   it that fails too, give up.
	 */
	i = pwc_set_video_mode(pdev, pwc_image_sizes[pdev->vsize].x, pwc_image_sizes[pdev->vsize].y, pdev->vframes, pdev->vcompression, 0);
	if (i)	{
		Trace(TRACE_OPEN, "First attempt at set_video_mode failed.\n");
		if (pdev->type == 730 || pdev->type == 740 || pdev->type == 750)
			i = pwc_set_video_mode(pdev, pwc_image_sizes[PSZ_QSIF].x, pwc_image_sizes[PSZ_QSIF].y, 10, pdev->vcompression, 0);
		else
			i = pwc_set_video_mode(pdev, pwc_image_sizes[PSZ_QCIF].x, pwc_image_sizes[PSZ_QCIF].y, 10, pdev->vcompression, 0);
	}
	if (i) {
		Trace(TRACE_OPEN, "Second attempt at set_video_mode failed.\n");
		up(&pdev->modlock);
		return i;
	}
	
	i = pwc_isoc_init(pdev);
	if (i) {
		Trace(TRACE_OPEN, "Failed to init ISOC stuff = %d.\n", i);
		up(&pdev->modlock);
		return i;
	}

	pdev->vopen++;
	/* lock decompressor; this has a small race condition, since we 
	   could in theory unload pwcx.o between pwc_find_decompressor()
	   above and this call. I doubt it's ever going to be a problem.
	 */
	if (pdev->decompressor != NULL)
		pdev->decompressor->lock();
	up(&pdev->modlock);
	Trace(TRACE_OPEN, "<< video_open() returns 0.\n");
	return 0;
}

/* Note that all cleanup is done in the reverse order as in _open */
static void pwc_video_close(struct video_device *vdev)
{
	struct pwc_device *pdev;
	int i;

	Trace(TRACE_OPEN, ">> video_close called(vdev = 0x%p).\n", vdev);

	pdev = (struct pwc_device *)vdev->priv;
	if (pdev->vopen == 0)
		Info("video_close() called on closed device?\n");

	/* Dump statistics, but only if a reasonable amount of frames were
	   processed (to prevent endless log-entries in case of snap-shot
	   programs)
	 */
	if (pdev->vframe_count > 20)
		Info("Closing video device: %d frames received, dumped %d frames, %d frames with errors.\n", pdev->vframe_count, pdev->vframes_dumped, pdev->vframes_error);

	if (pdev->decompressor != NULL) {
		pdev->decompressor->exit();
		pdev->decompressor->unlock();
		pdev->decompressor = NULL;
	}

	pwc_isoc_cleanup(pdev);
	pwc_free_buffers(pdev);

	/* Turn off LEDS and power down camera, but only when not unplugged */
	if (pdev->error_status != EPIPE) {
		/* Turn LEDs off */
		if (pwc_set_leds(pdev, 0, 0) < 0)
			Info("Failed to set LED on/off time.\n");
		if (power_save) {
			i = pwc_camera_power(pdev, 0);
			if (i < 0)
				Err("Failed to power down camera (%d)\n", i);
		}
	}
	pdev->vopen = 0;
	Trace(TRACE_OPEN, "<< video_close()\n");
}

/*
 *	FIXME: what about two parallel reads ????
 *      ANSWER: Not supported. You can't open the device more than once,
                despite what the V4L1 interface says. First, I don't see
                the need, second there's no mechanism of alerting the
                2nd/3rd/... process of events like changing image size.
                And I don't see the point of blocking that for the
                2nd/3rd/... process.
                In multi-threaded environments reading parallel from any
                device is tricky anyhow.
 */

static long pwc_video_read(struct video_device *vdev, char *buf, unsigned long count, int noblock)
{
	struct pwc_device *pdev;
	DECLARE_WAITQUEUE(wait, current);
        int bytes_to_read;

	Trace(TRACE_READ, "video_read(0x%p, %p, %ld, %d) called.\n", vdev, buf, count, noblock);
	if (vdev == NULL)
		return -EFAULT;
	pdev = vdev->priv;
	if (pdev == NULL)
		return -EFAULT;
	if (pdev->error_status)
		return -pdev->error_status; /* Something happened, report what. */

	/* In case we're doing partial reads, we don't have to wait for a frame */
	if (pdev->image_read_pos == 0) {
		/* Do wait queueing according to the (doc)book */
		add_wait_queue(&pdev->frameq, &wait);
		while (pdev->full_frames == NULL) {
			/* Check for unplugged/etc. here */
			if (pdev->error_status) {
				remove_wait_queue(&pdev->frameq, &wait);
				set_current_state(TASK_RUNNING);
				return -pdev->error_status ;
			}
	                if (noblock) {
	                	remove_wait_queue(&pdev->frameq, &wait);
	                	set_current_state(TASK_RUNNING);
	                	return -EWOULDBLOCK;
	                }
	                if (signal_pending(current)) {
	                	remove_wait_queue(&pdev->frameq, &wait);
	                	set_current_state(TASK_RUNNING);
	                	return -ERESTARTSYS;
	                }
	                schedule();
	               	set_current_state(TASK_INTERRUPTIBLE);
		}
		remove_wait_queue(&pdev->frameq, &wait);
		set_current_state(TASK_RUNNING);

		/* Decompress and release frame */
		if (pwc_handle_frame(pdev))
			return -EFAULT;
	}

	Trace(TRACE_READ, "Copying data to user space.\n");
	if (pdev->vpalette == VIDEO_PALETTE_RAW)
		bytes_to_read = pdev->frame_size;
	else
 		bytes_to_read = pdev->view.size;

	/* copy bytes to user space; we allow for partial reads */
	if (count + pdev->image_read_pos > bytes_to_read)
		count = bytes_to_read - pdev->image_read_pos;
	if (copy_to_user(buf, pdev->image_ptr[pdev->fill_image] + pdev->image_read_pos, count))
		return -EFAULT;
	pdev->image_read_pos += count;
	if (pdev->image_read_pos >= bytes_to_read) { /* All data has been read */
		pdev->image_read_pos = 0;
		pwc_next_image(pdev);
	}
	return count;
}


static long pwc_video_write(struct video_device *vdev, const char *buf, unsigned long count, int noblock)
{
	return -EINVAL;
}

static unsigned int pwc_video_poll(struct video_device *vdev, struct file *file, poll_table *wait)
{
	struct pwc_device *pdev;

	if (vdev == NULL)
		return -EFAULT;
	pdev = vdev->priv;
	if (pdev == NULL)
		return -EFAULT;

	poll_wait(file, &pdev->frameq, wait);
	if (pdev->error_status)
		return POLLERR;
	if (pdev->full_frames != NULL) /* we have frames waiting */
		return (POLLIN | POLLRDNORM);

	return 0;
}

static int pwc_video_ioctl(struct video_device *vdev, unsigned int cmd, void *arg)
{
	struct pwc_device *pdev;
	DECLARE_WAITQUEUE(wait, current);

	if (vdev == NULL)
		return -EFAULT;
	pdev = vdev->priv;
	if (pdev == NULL)
		return -EFAULT;

	switch (cmd) {
		/* Query cabapilities */
		case VIDIOCGCAP:
		{
			struct video_capability caps;

			strcpy(caps.name, vdev->name);
			caps.type = VID_TYPE_CAPTURE;
			caps.channels = 1;
			caps.audios = 1;
			caps.minwidth  = pdev->view_min.x;
			caps.minheight = pdev->view_min.y;
			caps.maxwidth  = pdev->view_max.x;
			caps.maxheight = pdev->view_max.y;
			if (copy_to_user(arg, &caps, sizeof(caps)))
				return -EFAULT;
			break;
		}

		/* Channel functions (simulate 1 channel) */
		case VIDIOCGCHAN:
		{
			struct video_channel v;

			if (copy_from_user(&v, arg, sizeof(v)))
				return -EFAULT;
			if (v.channel != 0)
				return -EINVAL;

			v.flags = 0;
			v.tuners = 0;
			v.type = VIDEO_TYPE_CAMERA;
			strcpy(v.name, "Webcam");

			if (copy_to_user(arg, &v, sizeof(v)))
				return -EFAULT;

			return 0;
		}

		case VIDIOCSCHAN:
		{
			/* The spec says the argument is an integer, but
			   the bttv driver uses a video_channel arg, which
			   makes sense becasue it also has the norm flag.
			 */
			struct video_channel v;

			if (copy_from_user(&v, arg, sizeof(v)))
				return -EFAULT;

			if (v.channel != 0)
				return -EINVAL;

			return 0;
		}


		/* Picture functions; contrast etc. */
		case VIDIOCGPICT:
		{
			struct video_picture p;
			int val;

			val = pwc_get_brightness(pdev);
			if (val >= 0)
				p.brightness = val;
			else
				p.brightness = 0xffff;
			val = pwc_get_contrast(pdev);
			if (val >= 0)
				p.contrast = val;
			else
				p.contrast = 0xffff;
			/* Gamma, Whiteness, what's the difference? :) */
			val = pwc_get_gamma(pdev);
			if (val >= 0)
				p.whiteness = val;
			else
				p.whiteness = 0xffff;
			val = pwc_get_saturation(pdev);
			if (val >= 0)
				p.colour = val;
			else
				p.colour = 0xffff;
			p.depth = 24;
			p.palette = pdev->vpalette;
			p.hue = 0xFFFF; /* N/A */