[net-next-2.6.git] / drivers / media / video / em28xx / em28xx-vbi.c

/*
   em28xx-vbi.c - VBI driver for em28xx

   Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>

   This work was sponsored by EyeMagnet Limited.

   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 <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>

#include "em28xx.h"

static unsigned int vbibufs = 5;
module_param(vbibufs, int, 0644);
MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32");

static unsigned int vbi_debug;
module_param(vbi_debug, int, 0644);
MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]");

#define dprintk(level, fmt, arg...)	if (vbi_debug >= level) \
	printk(KERN_DEBUG "%s: " fmt, dev->core->name , ## arg)

/* ------------------------------------------------------------------ */

static void
free_buffer(struct videobuf_queue *vq, struct em28xx_buffer *buf)
{
	struct em28xx_fh     *fh  = vq->priv_data;
	struct em28xx        *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 em28xx_fh     *fh  = q->priv_data;
	struct em28xx        *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 em28xx_fh     *fh  = q->priv_data;
	struct em28xx        *dev = fh->dev;
	struct em28xx_buffer *buf = container_of(vb, struct em28xx_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 em28xx_buffer    *buf     = container_of(vb,
							struct em28xx_buffer,
							vb);
	struct em28xx_fh        *fh      = vq->priv_data;
	struct em28xx           *dev     = fh->dev;
	struct em28xx_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 em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
	free_buffer(q, buf);
}

struct videobuf_queue_ops em28xx_vbi_qops = {
	.buf_setup    = vbi_setup,
	.buf_prepare  = vbi_prepare,
	.buf_queue    = vbi_queue,
	.buf_release  = vbi_release,
};
Commit	Line	Data
28abf083 DH	1	/*
	2	em28xx-vbi.c - VBI driver for em28xx
	3
	4	Copyright (C) 2009 Devin Heitmueller <dheitmueller@kernellabs.com>
	5
	6	This work was sponsored by EyeMagnet Limited.
	7
	8	This program is free software; you can redistribute it and/or modify
	9	it under the terms of the GNU General Public License as published by
	10	the Free Software Foundation; either version 2 of the License, or
	11	(at your option) any later version.
	12
	13	This program is distributed in the hope that it will be useful,
	14	but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	GNU General Public License for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with this program; if not, write to the Free Software
	20	Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
	21	02110-1301, USA.
	22	*/
	23
	24	#include <linux/kernel.h>
	25	#include <linux/module.h>
	26	#include <linux/init.h>
28abf083 DH	27
	28	#include "em28xx.h"
	29
	30	static unsigned int vbibufs = 5;
cb0409ff DH	31	module_param(vbibufs, int, 0644);
cb0409ff DH	32	MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32");
28abf083 DH	33
28abf083 DH	34	static unsigned int vbi_debug;
cb0409ff DH	35	module_param(vbi_debug, int, 0644);
cb0409ff DH	36	MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]");
28abf083	37
cb0409ff	38	#define dprintk(level, fmt, arg...) if (vbi_debug >= level) \
28abf083 DH	39	printk(KERN_DEBUG "%s: " fmt, dev->core->name , ## arg)
	40
	41	/* ------------------------------------------------------------------ */
	42
	43	static void
	44	free_buffer(struct videobuf_queue vq, struct em28xx_buffer buf)
	45	{
	46	struct em28xx_fh *fh = vq->priv_data;
	47	struct em28xx *dev = fh->dev;
	48	unsigned long flags = 0;
	49	if (in_interrupt())
	50	BUG();
	51
	52	/* We used to wait for the buffer to finish here, but this didn't work
	53	because, as we were keeping the state as VIDEOBUF_QUEUED,
	54	videobuf_queue_cancel marked it as finished for us.
	55	(Also, it could wedge forever if the hardware was misconfigured.)
	56
	57	This should be safe; by the time we get here, the buffer isn't
	58	queued anymore. If we ever start marking the buffers as
	59	VIDEOBUF_ACTIVE, it won't be, though.
	60	*/
	61	spin_lock_irqsave(&dev->slock, flags);
	62	if (dev->isoc_ctl.vbi_buf == buf)
	63	dev->isoc_ctl.vbi_buf = NULL;
	64	spin_unlock_irqrestore(&dev->slock, flags);
	65
	66	videobuf_vmalloc_free(&buf->vb);
	67	buf->vb.state = VIDEOBUF_NEEDS_INIT;
	68	}
	69
	70	static int
	71	vbi_setup(struct videobuf_queue q, unsigned int count, unsigned int *size)
	72	{
66d9cbad DH	73	struct em28xx_fh *fh = q->priv_data;
	74	struct em28xx *dev = fh->dev;
	75
	76	size = dev->vbi_width dev->vbi_height * 2;
	77
28abf083 DH	78	if (0 == *count)
	79	*count = vbibufs;
	80	if (*count < 2)
	81	*count = 2;
	82	if (*count > 32)
	83	*count = 32;
	84	return 0;
	85	}
	86
	87	static int
	88	vbi_prepare(struct videobuf_queue q, struct videobuf_buffer vb,
	89	enum v4l2_field field)
	90	{
66d9cbad DH	91	struct em28xx_fh *fh = q->priv_data;
66d9cbad DH	92	struct em28xx *dev = fh->dev;
28abf083 DH	93	struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
28abf083 DH	94	int rc = 0;
28abf083	95
66d9cbad	96	buf->vb.size = dev->vbi_width * dev->vbi_height * 2;
28abf083 DH	97
	98	if (0 != buf->vb.baddr && buf->vb.bsize < buf->vb.size)
	99	return -EINVAL;
	100
66d9cbad DH	101	buf->vb.width = dev->vbi_width;
66d9cbad DH	102	buf->vb.height = dev->vbi_height;
28abf083 DH	103	buf->vb.field = field;
	104
	105	if (VIDEOBUF_NEEDS_INIT == buf->vb.state) {
	106	rc = videobuf_iolock(q, &buf->vb, NULL);
	107	if (rc < 0)
	108	goto fail;
	109	}
	110
	111	buf->vb.state = VIDEOBUF_PREPARED;
	112	return 0;
	113
	114	fail:
	115	free_buffer(q, buf);
	116	return rc;
	117	}
	118
	119	static void
	120	vbi_queue(struct videobuf_queue vq, struct videobuf_buffer vb)
	121	{
	122	struct em28xx_buffer *buf = container_of(vb,
	123	struct em28xx_buffer,
	124	vb);
	125	struct em28xx_fh *fh = vq->priv_data;
	126	struct em28xx *dev = fh->dev;
	127	struct em28xx_dmaqueue *vbiq = &dev->vbiq;
	128
	129	buf->vb.state = VIDEOBUF_QUEUED;
	130	list_add_tail(&buf->vb.queue, &vbiq->active);
	131	}
	132
	133	static void vbi_release(struct videobuf_queue q, struct videobuf_buffer vb)
	134	{
	135	struct em28xx_buffer *buf = container_of(vb, struct em28xx_buffer, vb);
	136	free_buffer(q, buf);
	137	}
	138
	139	struct videobuf_queue_ops em28xx_vbi_qops = {
	140	.buf_setup = vbi_setup,
	141	.buf_prepare = vbi_prepare,
	142	.buf_queue = vbi_queue,
	143	.buf_release = vbi_release,
	144	};