V4L/DVB: uvc: Fix multiple symbols definitions with UVC gadget and host drivers

The UVC gadget driver borrowed code from the UVC host driver without
changing the symbol names. This results in a namespace clash with
multiple definitions of several symbols when compiling both drivers in
the kernel.

Make all generic UVC functions and variables static in the UVC gadget
driver, as the symbols are not referenced outside of the gadget driver.
Rename the uvc_trace_param global variable to uvc_gadget_trace_param.

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

1 files changed, 79 insertions, 74 deletions

diff --git a/drivers/usb/gadget/uvc_queue.c b/drivers/usb/gadget/uvc_queue.c
index 43891991bf21..f7395ac5dc17 100644
--- a/drivers/usb/gadget/uvc_queue.c
+++ b/drivers/usb/gadget/uvc_queue.c
@@ -78,7 +78,8 @@
  *
  */
 
-void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
+static void
+uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 {
         mutex_init(&queue->mutex);
         spin_lock_init(&queue->irqlock);
@@ -88,6 +89,28 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
 }
 
 /*
+ * Free the video buffers.
+ *
+ * This function must be called with the queue lock held.
+ */
+static int uvc_free_buffers(struct uvc_video_queue *queue)
+{
+        unsigned int i;
+
+        for (i = 0; i < queue->count; ++i) {
+                if (queue->buffer[i].vma_use_count != 0)
+                        return -EBUSY;
+        }
+
+        if (queue->count) {
+                vfree(queue->mem);
+                queue->count = 0;
+        }
+
+        return 0;
+}
+
+/*
  * Allocate the video buffers.
  *
  * Pages are reserved to make sure they will not be swapped, as they will be
@@ -95,8 +118,9 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type)
  *
  * Buffers will be individually mapped, so they must all be page aligned.
  */
-int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
-                unsigned int buflength)
+static int
+uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
+                  unsigned int buflength)
 {
         unsigned int bufsize = PAGE_ALIGN(buflength);
         unsigned int i;
@@ -150,28 +174,6 @@ done:
         return ret;
 }
 
-/*
- * Free the video buffers.
- *
- * This function must be called with the queue lock held.
- */
-int uvc_free_buffers(struct uvc_video_queue *queue)
-{
-        unsigned int i;
-
-        for (i = 0; i < queue->count; ++i) {
-                if (queue->buffer[i].vma_use_count != 0)
-                        return -EBUSY;
-        }
-
-        if (queue->count) {
-                vfree(queue->mem);
-                queue->count = 0;
-        }
-
-        return 0;
-}
-
 static void __uvc_query_buffer(struct uvc_buffer *buf,
                 struct v4l2_buffer *v4l2_buf)
 {
@@ -195,8 +197,8 @@ static void __uvc_query_buffer(struct uvc_buffer *buf,
         }
 }
 
-int uvc_query_buffer(struct uvc_video_queue *queue,
-                struct v4l2_buffer *v4l2_buf)
+static int
+uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf)
 {
         int ret = 0;
 
@@ -217,8 +219,8 @@ done:
  * Queue a video buffer. Attempting to queue a buffer that has already been
  * queued will return -EINVAL.
  */
-int uvc_queue_buffer(struct uvc_video_queue *queue,
-        struct v4l2_buffer *v4l2_buf)
+static int
+uvc_queue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf)
 {
         struct uvc_buffer *buf;
         unsigned long flags;
@@ -298,8 +300,9 @@ static int uvc_queue_waiton(struct uvc_buffer *buf, int nonblocking)
  * Dequeue a video buffer. If nonblocking is false, block until a buffer is
  * available.
  */
-int uvc_dequeue_buffer(struct uvc_video_queue *queue,
-                struct v4l2_buffer *v4l2_buf, int nonblocking)
+static int
+uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *v4l2_buf,
+                   int nonblocking)
 {
         struct uvc_buffer *buf;
         int ret = 0;
@@ -359,8 +362,9 @@ done:
  * This function implements video queue polling and is intended to be used by
  * the device poll handler.
  */
-unsigned int uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
-                poll_table *wait)
+static unsigned int
+uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
+               poll_table *wait)
 {
         struct uvc_buffer *buf;
         unsigned int mask = 0;
@@ -407,7 +411,8 @@ static struct vm_operations_struct uvc_vm_ops = {
  * This function implements video buffer memory mapping and is intended to be
  * used by the device mmap handler.
  */
-int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
+static int
+uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
 {
         struct uvc_buffer *uninitialized_var(buffer);
         struct page *page;
@@ -458,6 +463,42 @@ done:
 }
 
 /*
+ * Cancel the video buffers queue.
+ *
+ * Cancelling the queue marks all buffers on the irq queue as erroneous,
+ * 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.
+ *
+ * This function acquires the irq spinlock and can be called from interrupt
+ * context.
+ */
+static void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
+{
+        struct uvc_buffer *buf;
+        unsigned long flags;
+
+        spin_lock_irqsave(&queue->irqlock, flags);
+        while (!list_empty(&queue->irqqueue)) {
+                buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
+                                       queue);
+                list_del(&buf->queue);
+                buf->state = UVC_BUF_STATE_ERROR;
+                wake_up(&buf->wait);
+        }
+        /* This must be protected by the irqlock spinlock to avoid race
+         * conditions between uvc_queue_buffer and the disconnection event that
+         * could result in an interruptible wait in uvc_dequeue_buffer. Do not
+         * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
+         * state outside the queue code.
+         */
+        if (disconnect)
+                queue->flags |= UVC_QUEUE_DISCONNECTED;
+        spin_unlock_irqrestore(&queue->irqlock, flags);
+}
+
+/*
  * Enable or disable the video buffers queue.
  *
  * The queue must be enabled before starting video acquisition and must be
@@ -474,7 +515,7 @@ done:
  * This function can't be called from interrupt context. Use
  * uvc_queue_cancel() instead.
  */
-int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
+static int uvc_queue_enable(struct uvc_video_queue *queue, int enable)
 {
         unsigned int i;
         int ret = 0;
@@ -503,44 +544,8 @@ done:
         return ret;
 }
 
-/*
- * Cancel the video buffers queue.
- *
- * Cancelling the queue marks all buffers on the irq queue as erroneous,
- * 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.
- *
- * This function acquires the irq spinlock and can be called from interrupt
- * context.
- */
-void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
-{
-        struct uvc_buffer *buf;
-        unsigned long flags;
-
-        spin_lock_irqsave(&queue->irqlock, flags);
-        while (!list_empty(&queue->irqqueue)) {
-                buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
-                                       queue);
-                list_del(&buf->queue);
-                buf->state = UVC_BUF_STATE_ERROR;
-                wake_up(&buf->wait);
-        }
-        /* This must be protected by the irqlock spinlock to avoid race
-         * conditions between uvc_queue_buffer and the disconnection event that
-         * could result in an interruptible wait in uvc_dequeue_buffer. Do not
-         * blindly replace this logic by checking for the UVC_DEV_DISCONNECTED
-         * state outside the queue code.
-         */
-        if (disconnect)
-                queue->flags |= UVC_QUEUE_DISCONNECTED;
-        spin_unlock_irqrestore(&queue->irqlock, flags);
-}
-
-struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
-                struct uvc_buffer *buf)
+static struct uvc_buffer *
+uvc_queue_next_buffer(struct uvc_video_queue *queue, struct uvc_buffer *buf)
 {
         struct uvc_buffer *nextbuf;
         unsigned long flags;
@@ -568,7 +573,7 @@ struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
         return nextbuf;
 }
 
-struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue)
+static struct uvc_buffer *uvc_queue_head(struct uvc_video_queue *queue)
 {
         struct uvc_buffer *buf = NULL;