Fixed MTP to work with TWRP

drivers/media/usb/au0828/au0828-vbi.c

@@ -0,0 +1,138 @@
+/*
+   au0828-vbi.c - VBI driver for au0828
+
+   Copyright (C) 2010 Devin Heitmueller <dheitmueller@kernellabs.com>
+
+   This work was sponsored by GetWellNetwork Inc.
+
+   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
+   the Free Software Foundation; either version 2 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+   02110-1301, USA.
+ */
+
+#include "au0828.h"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+
+static unsigned int vbibufs = 5;
+module_param(vbibufs, int, 0644);
+MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32");
+
+/* ------------------------------------------------------------------ */
+
+static void
+free_buffer(struct videobuf_queue *vq, struct au0828_buffer *buf)
+{
+	struct au0828_fh     *fh  = vq->priv_data;
+	struct au0828_dev    *dev = fh->dev;
+	unsigned long flags = 0;
+	if (in_interrupt())
+		BUG();
+
+	/* We used to wait for the buffer to finish here, but this didn't work
+	   because, as we were keeping the state as VIDEOBUF_QUEUED,
+	   videobuf_queue_cancel marked it as finished for us.
+	   (Also, it could wedge forever if the hardware was misconfigured.)
+
+	   This should be safe; by the time we get here, the buffer isn't
+	   queued anymore. If we ever start marking the buffers as
+	   VIDEOBUF_ACTIVE, it won't be, though.
+	*/
+	spin_lock_irqsave(&dev->slock, flags);
+	if (dev->isoc_ctl.vbi_buf == buf)
+		dev->isoc_ctl.vbi_buf = NULL;
+	spin_unlock_irqrestore(&dev->slock, flags);
+
+	videobuf_vmalloc_free(&buf->vb);
+	buf->vb.state = VIDEOBUF_NEEDS_INIT;
+}
+
+static int
+vbi_setup(struct videobuf_queue *q, unsigned int *count, unsigned int *size)
+{
+	struct au0828_fh     *fh  = q->priv_data;
+	struct au0828_dev    *dev = fh->dev;
+
+	*size = dev->vbi_width * dev->vbi_height * 2;
+
+	if (0 == *count)
+		*count = vbibufs;
+	if (*count < 2)
+		*count = 2;
+	if (*count > 32)
+		*count = 32;
+	return 0;
+}
+
+static int
+vbi_prepare(struct videobuf_queue *q, struct videobuf_buffer *vb,
+	    enum v4l2_field field)
+{
+	struct au0828_fh     *fh  = q->priv_data;
+	struct au0828_dev    *dev = fh->dev;
+	struct au0828_buffer *buf = container_of(vb, struct au0828_buffer, vb);
+	int                  rc = 0;
+
+	buf->vb.size = dev->vbi_width * dev->vbi_height * 2;
+
+	if (0 != buf->vb.baddr  &&  buf->vb.bsize < buf->vb.size)
+		return -EINVAL;
+
+	buf->vb.width  = dev->vbi_width;
+	buf->vb.height = dev->vbi_height;
+	buf->vb.field  = field;
+
+	if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
+		rc = videobuf_iolock(q, &buf->vb, NULL);
+		if (rc < 0)
+			goto fail;
+	}
+
+	buf->vb.state = VIDEOBUF_PREPARED;
+	return 0;
+
+fail:
+	free_buffer(q, buf);
+	return rc;
+}
+
+static void
+vbi_queue(struct videobuf_queue *vq, struct videobuf_buffer *vb)
+{
+	struct au0828_buffer    *buf     = container_of(vb,
+							struct au0828_buffer,
+							vb);
+	struct au0828_fh        *fh      = vq->priv_data;
+	struct au0828_dev       *dev     = fh->dev;
+	struct au0828_dmaqueue  *vbiq    = &dev->vbiq;
+
+	buf->vb.state = VIDEOBUF_QUEUED;
+	list_add_tail(&buf->vb.queue, &vbiq->active);
+}
+
+static void vbi_release(struct videobuf_queue *q, struct videobuf_buffer *vb)
+{
+	struct au0828_buffer *buf = container_of(vb, struct au0828_buffer, vb);
+	free_buffer(q, buf);
+}
+
+struct videobuf_queue_ops au0828_vbi_qops = {
+	.buf_setup    = vbi_setup,
+	.buf_prepare  = vbi_prepare,
+	.buf_queue    = vbi_queue,
+	.buf_release  = vbi_release,
+};