V4L/DVB (10197): uvcvideo: Whitespace and comments cleanup, copyright updates.

Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/uvc/uvc_ctrl.c

 /*
  *      uvc_ctrl.c  --  USB Video Class driver - Controls
  *
- *      Copyright (C) 2005-2008
+ *      Copyright (C) 2005-2009
  *          Laurent Pinchart (laurent.pinchart@skynet.be)
  *
  *      This program is free software; you can redistribute it and/or modify
@@ -28,7 +28,7 @@
 #define UVC_CTRL_DATA_BACKUP	1
 
 /* ------------------------------------------------------------------------
- * Control, formats, ...
+ * Controls
  */
 
 static struct uvc_control_info uvc_ctrls[] = {
@@ -634,7 +634,7 @@ static __s32 uvc_get_le_value(struct uvc_control_mapping *mapping,
 		mask = (1 << bits) - 1;
 	}
 
-	/* Sign-extend the value if needed */
+	/* Sign-extend the value if needed. */
 	if (mapping->data_type == UVC_CTRL_DATA_TYPE_SIGNED)
 		value |= -(value & (1 << (mapping->size - 1)));
 

drivers/media/video/uvc/uvc_driver.c

 /*
  *      uvc_driver.c  --  USB Video Class driver
  *
- *      Copyright (C) 2005-2008
+ *      Copyright (C) 2005-2009
  *          Laurent Pinchart (laurent.pinchart@skynet.be)
  *
  *      This program is free software; you can redistribute it and/or modify
@@ -48,7 +48,7 @@ static unsigned int uvc_quirks_param;
 unsigned int uvc_trace_param;
 
 /* ------------------------------------------------------------------------
- * Control, formats, ...
+ * Video formats
  */
 
 static struct uvc_format_desc uvc_fmts[] = {
@@ -473,7 +473,7 @@ static int uvc_parse_format(struct uvc_device *dev,
 
 		/* Several UVC chipsets screw up dwMaxVideoFrameBufferSize
 		 * completely. Observed behaviours range from setting the
-		 * value to 1.1x the actual frame size of hardwiring the
+		 * value to 1.1x the actual frame size to hardwiring the
 		 * 16 low bits to 0. This results in a higher than necessary
 		 * memory usage as well as a wrong image size information. For
 		 * uncompressed formats this can be fixed by computing the
@@ -486,7 +486,7 @@ static int uvc_parse_format(struct uvc_device *dev,
 		/* Some bogus devices report dwMinFrameInterval equal to
 		 * dwMaxFrameInterval and have dwFrameIntervalStep set to
 		 * zero. Setting all null intervals to 1 fixes the problem and
-		 * some other divisions by zero which could happen.
+		 * some other divisions by zero that could happen.
 		 */
 		for (i = 0; i < n; ++i) {
 			interval = get_unaligned_le32(&buffer[26+4*i]);
@@ -1199,13 +1199,13 @@ static void uvc_unregister_video(struct uvc_device *dev)
  * Scan the UVC descriptors to locate a chain starting at an Output Terminal
  * and containing the following units:
  *
- * - a USB Streaming Output Terminal
+ * - one Output Terminal (USB Streaming or Display)
  * - zero or one Processing Unit
  * - zero, one or mode single-input Selector Units
  * - zero or one multiple-input Selector Units, provided all inputs are
  *   connected to input terminals
  * - zero, one or mode single-input Extension Units
- * - one Camera Input Terminal, or one or more External terminals.
+ * - one or more Input Terminals (Camera, External or USB Streaming)
  *
  * A side forward scan is made on each detected entity to check for additional
  * extension units.
@@ -1530,10 +1530,6 @@ static int uvc_register_video(struct uvc_device *dev)
 
 	/* Set the driver data before calling video_register_device, otherwise
 	 * uvc_v4l2_open might race us.
-	 *
-	 * FIXME: usb_set_intfdata hasn't been called so far. Is that a
-	 * 	  problem ? Does any function which could be called here get
-	 * 	  a pointer to the usb_interface ?
 	 */
 	dev->video.vdev = vdev;
 	video_set_drvdata(vdev, &dev->video);
@@ -1568,7 +1564,7 @@ void uvc_delete(struct kref *kref)
 	struct uvc_device *dev = container_of(kref, struct uvc_device, kref);
 	struct list_head *p, *n;
 
-	/* Unregister the video device */
+	/* Unregister the video device. */
 	uvc_unregister_video(dev);
 	usb_put_intf(dev->intf);
 	usb_put_dev(dev->udev);
@@ -1611,7 +1607,7 @@ static int uvc_probe(struct usb_interface *intf,
 		uvc_trace(UVC_TRACE_PROBE, "Probing generic UVC device %s\n",
 				udev->devpath);
 
-	/* Allocate memory for the device and initialize it */
+	/* Allocate memory for the device and initialize it. */
 	if ((dev = kzalloc(sizeof *dev, GFP_KERNEL)) == NULL)
 		return -ENOMEM;
 
@@ -1632,7 +1628,7 @@ static int uvc_probe(struct usb_interface *intf,
 			le16_to_cpu(udev->descriptor.idVendor),
 			le16_to_cpu(udev->descriptor.idProduct));
 
-	/* Parse the Video Class control descriptor */
+	/* Parse the Video Class control descriptor. */
 	if (uvc_parse_control(dev) < 0) {
 		uvc_trace(UVC_TRACE_PROBE, "Unable to parse UVC "
 			"descriptors.\n");
@@ -1652,18 +1648,18 @@ static int uvc_probe(struct usb_interface *intf,
 			"linux-uvc-devel mailing list.\n");
 	}
 
-	/* Initialize controls */
+	/* Initialize controls. */
 	if (uvc_ctrl_init_device(dev) < 0)
 		goto error;
 
-	/* Register the video devices */
+	/* Register the video devices. */
 	if (uvc_register_video(dev) < 0)
 		goto error;
 
-	/* Save our data pointer in the interface data */
+	/* Save our data pointer in the interface data. */
 	usb_set_intfdata(intf, dev);
 
-	/* Initialize the interrupt URB */
+	/* Initialize the interrupt URB. */
 	if ((ret = uvc_status_init(dev)) < 0) {
 		uvc_printk(KERN_INFO, "Unable to initialize the status "
 			"endpoint (%d), status interrupt will not be "

drivers/media/video/uvc/uvc_isight.c

@@ -3,6 +3,8 @@
  *
  *	Copyright (C) 2006-2007
  *		Ivan N. Zlatev <contact@i-nz.net>
+ *	Copyright (C) 2008-2009
+ *		Laurent Pinchart <laurent.pinchart@skynet.be>
  *
  *      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

drivers/media/video/uvc/uvc_queue.c

 /*
  *      uvc_queue.c  --  USB Video Class driver - Buffers management
  *
- *      Copyright (C) 2005-2008
+ *      Copyright (C) 2005-2009
  *          Laurent Pinchart (laurent.pinchart@skynet.be)
  *
  *      This program is free software; you can redistribute it and/or modify
@@ -36,22 +36,22 @@
  * to user space will return -EBUSY.
  *
  * Video buffers are managed using two queues. However, unlike most USB video
- * drivers which use an in queue and an out queue, we use a main queue which
- * holds all queued buffers (both 'empty' and 'done' buffers), and an irq
- * queue which holds empty buffers. This design (copied from video-buf)
- * minimizes locking in interrupt, as only one queue is shared between
- * interrupt and user contexts.
+ * drivers that use an in queue and an out queue, we use a main queue to hold
+ * all queued buffers (both 'empty' and 'done' buffers), and an irq queue to
+ * hold empty buffers. This design (copied from video-buf) minimizes locking
+ * in interrupt, as only one queue is shared between interrupt and user
+ * contexts.
  *
  * Use cases
  * ---------
  *
- * Unless stated otherwise, all operations which modify the irq buffers queue
+ * Unless stated otherwise, all operations that modify the irq buffers queue
  * are protected by the irq spinlock.
  *
  * 1. The user queues the buffers, starts streaming and dequeues a buffer.
  *
  *    The buffers are added to the main and irq queues. Both operations are
- *    protected by the queue lock, and the latert is protected by the irq
+ *    protected by the queue lock, and the later is protected by the irq
  *    spinlock as well.
  *
  *    The completion handler fetches a buffer from the irq queue and fills it
@@ -59,7 +59,7 @@
  *    returns immediately.
  *
  *    When the buffer is full, the completion handler removes it from the irq
- *    queue, marks it as ready (UVC_BUF_STATE_DONE) and wake its wait queue.
+ *    queue, marks it as ready (UVC_BUF_STATE_DONE) and wakes its wait queue.
  *    At that point, any process waiting on the buffer will be woken up. If a
  *    process tries to dequeue a buffer after it has been marked ready, the
  *    dequeing will succeed immediately.
@@ -90,8 +90,8 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 /*
  * Allocate the video buffers.
  *
- * Pages are reserved to make sure they will not be swaped, as they will be
- * filled in URB completion handler.
+ * Pages are reserved to make sure they will not be swapped, as they will be
+ * filled in the URB completion handler.
  *
  * Buffers will be individually mapped, so they must all be page aligned.
  */
@@ -428,7 +428,7 @@ int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
  * Cancel the video buffers queue.
  *
  * Cancelling the queue marks all buffers on the irq queue as erroneous,
- * wakes them up and remove them from the queue.
+ * wakes them up and removes them from the queue.
  *
  * If the disconnect parameter is set, further calls to uvc_queue_buffer will
  * fail with -ENODEV.

drivers/media/video/uvc/uvc_status.c

 /*
  *      uvc_status.c  --  USB Video Class driver - Status endpoint
  *
- *      Copyright (C) 2007-2008
+ *      Copyright (C) 2007-2009
  *          Laurent Pinchart (laurent.pinchart@skynet.be)
  *
  *      This program is free software; you can redistribute it and/or modify

drivers/media/video/uvc/uvc_v4l2.c

 /*
  *      uvc_v4l2.c  --  USB Video Class driver - V4L2 API
  *
- *      Copyright (C) 2005-2008
+ *      Copyright (C) 2005-2009
  *          Laurent Pinchart (laurent.pinchart@skynet.be)
  *
  *      This program is free software; you can redistribute it and/or modify
@@ -37,7 +37,7 @@
  * must be grouped (for instance the Red Balance, Blue Balance and Do White
  * Balance V4L2 controls use the White Balance Component UVC control) or
  * otherwise translated. The approach we take here is to use a translation
- * table for the controls which can be mapped directly, and handle the others
+ * table for the controls that can be mapped directly, and handle the others
  * manually.
  */
 static int uvc_v4l2_query_menu(struct uvc_video_device *video,
@@ -189,7 +189,7 @@ static int uvc_v4l2_try_format(struct uvc_video_device *video,
 		probe->dwMaxVideoFrameSize =
 			video->streaming->ctrl.dwMaxVideoFrameSize;
 
-	/* Probe the device */
+	/* Probe the device. */
 	if ((ret = uvc_probe_video(video, probe)) < 0)
 		goto done;
 
@@ -354,11 +354,11 @@ static int uvc_v4l2_set_streamparm(struct uvc_video_device *video,
  *
  * Each open instance of a UVC device can either be in a privileged or
  * unprivileged state. Only a single instance can be in a privileged state at
- * a given time. Trying to perform an operation which requires privileges will
+ * a given time. Trying to perform an operation that requires privileges will
  * automatically acquire the required privileges if possible, or return -EBUSY
  * otherwise. Privileges are dismissed when closing the instance.
  *
- * Operations which require privileges are:
+ * Operations that require privileges are:
  *
  * - VIDIOC_S_INPUT
  * - VIDIOC_S_PARM

drivers/media/video/uvc/uvc_video.c

 /*
  *      uvc_video.c  --  USB Video Class driver - Video handling
  *
- *      Copyright (C) 2005-2008
+ *      Copyright (C) 2005-2009
  *          Laurent Pinchart (laurent.pinchart@skynet.be)
  *
  *      This program is free software; you can redistribute it and/or modify
@@ -159,7 +159,7 @@ static int uvc_get_video_ctrl(struct uvc_video_device *video,
 	}
 
 	/* Some broken devices return a null or wrong dwMaxVideoFrameSize.
-	 * Try to get the value from the format and frame descriptor.
+	 * Try to get the value from the format and frame descriptors.
 	 */
 	uvc_fixup_buffer_size(video, ctrl);
 	ret = 0;
@@ -190,9 +190,6 @@ static int uvc_set_video_ctrl(struct uvc_video_device *video,
 	*(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality);
 	*(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize);
 	*(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay);
-	/* Note: Some of the fields below are not required for IN devices (see
-	 * UVC spec, 4.3.1.1), but we still copy them in case support for OUT
-	 * devices is added in the future. */
 	put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]);
 	put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]);
 
@@ -399,7 +396,7 @@ static int uvc_video_decode_start(struct uvc_video_device *video,
 	 *
 	 * Empty buffers (bytesused == 0) don't trigger end of frame detection
 	 * as it doesn't make sense to return an empty buffer. This also
-	 * avoids detecting and of frame conditions at FID toggling if the
+	 * avoids detecting end of frame conditions at FID toggling if the
 	 * previous payload had the EOF bit set.
 	 */
 	if (fid != video->last_fid && buf->buf.bytesused != 0) {
@@ -452,6 +449,17 @@ static void uvc_video_decode_end(struct uvc_video_device *video,
 	}
 }
 
+/* Video payload encoding is handled by uvc_video_encode_header() and
+ * uvc_video_encode_data(). Only bulk transfers are currently supported.
+ *
+ * uvc_video_encode_header is called at the start of a payload. It adds header
+ * data to the transfer buffer and returns the header size. As the only known
+ * UVC output device transfers a whole frame in a single payload, the EOF bit
+ * is always set in the header.
+ *
+ * uvc_video_encode_data is called for every URB and copies the data from the
+ * video buffer to the transfer buffer.
+ */
 static int uvc_video_encode_header(struct uvc_video_device *video,
 		struct uvc_buffer *buf, __u8 *data, int len)
 {
@@ -952,7 +960,7 @@ int uvc_video_suspend(struct uvc_video_device *video)
 }
 
 /*
- * Reconfigure the video interface and restart streaming if it was enable
+ * Reconfigure the video interface and restart streaming if it was enabled
  * before suspend.
  *
  * If an error occurs, disable the video queue. This will wake all pending
@@ -984,8 +992,8 @@ int uvc_video_resume(struct uvc_video_device *video)
  */
 
 /*
- * Initialize the UVC video device by retrieving the default format and
- * committing it.
+ * Initialize the UVC video device by switching to alternate setting 0 and
+ * retrieve the default format.
  *
  * Some cameras (namely the Fuji Finepix) set the format and frame
  * indexes to zero. The UVC standard doesn't clearly make this a spec
@@ -1013,7 +1021,7 @@ int uvc_video_init(struct uvc_video_device *video)
 	 */
 	usb_set_interface(video->dev->udev, video->streaming->intfnum, 0);
 
-	/* Some webcams don't suport GET_DEF request on the probe control. We
+	/* Some webcams don't suport GET_DEF requests on the probe control. We
 	 * fall back to GET_CUR if GET_DEF fails.
 	 */
 	if ((ret = uvc_get_video_ctrl(video, probe, 1, GET_DEF)) < 0 &&