- 根目录:
- Documentation
- video4linux
- v4l2-pci-skeleton.c
/*
* This is a V4L2 PCI Skeleton Driver. It gives an initial skeleton source
* for use with other PCI drivers.
*
* This skeleton PCI driver assumes that the card has an S-Video connector as
* input 0 and an HDMI connector as input 1.
*
* Copyright 2014 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/mutex.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <linux/videodev2.h>
#include <linux/v4l2-dv-timings.h>
#include <media/v4l2-device.h>
#include <media/v4l2-dev.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-dv-timings.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>
#include <media/videobuf2-v4l2.h>
#include <media/videobuf2-dma-contig.h>
MODULE_DESCRIPTION("V4L2 PCI Skeleton Driver");
MODULE_AUTHOR("Hans Verkuil");
MODULE_LICENSE("GPL v2");
/**
* struct skeleton - All internal data for one instance of device
* @pdev: PCI device
* @v4l2_dev: top-level v4l2 device struct
* @vdev: video node structure
* @ctrl_handler: control handler structure
* @lock: ioctl serialization mutex
* @std: current SDTV standard
* @timings: current HDTV timings
* @format: current pix format
* @input: current video input (0 = SDTV, 1 = HDTV)
* @queue: vb2 video capture queue
* @alloc_ctx: vb2 contiguous DMA context
* @qlock: spinlock controlling access to buf_list and sequence
* @buf_list: list of buffers queued for DMA
* @sequence: frame sequence counter
*/
struct skeleton {
struct pci_dev *pdev;
struct v4l2_device v4l2_dev;
struct video_device vdev;
struct v4l2_ctrl_handler ctrl_handler;
struct mutex lock;
v4l2_std_id std;
struct v4l2_dv_timings timings;
struct v4l2_pix_format format;
unsigned input;
struct vb2_queue queue;
struct vb2_alloc_ctx *alloc_ctx;
spinlock_t qlock;
struct list_head buf_list;
unsigned field;
unsigned sequence;
};
struct skel_buffer {
struct vb2_buffer vb;
struct list_head list;
};
static inline struct skel_buffer *to_skel_buffer(struct vb2_buffer *vb2)
{
return container_of(vb2, struct skel_buffer, vb);
}
static const struct pci_device_id skeleton_pci_tbl[] = {
/* { PCI_DEVICE(PCI_VENDOR_ID_, PCI_DEVICE_ID_) }, */
{ 0, }
};
MODULE_DEVICE_TABLE(pci, skeleton_pci_tbl);
/*
* HDTV: this structure has the capabilities of the HDTV receiver.
* It is used to constrain the huge list of possible formats based
* upon the hardware capabilities.
*/
static const struct v4l2_dv_timings_cap skel_timings_cap = {
.type = V4L2_DV_BT_656_1120,
/* keep this initialization for compatibility with GCC < 4.4.6 */
.reserved = { 0 },
V4L2_INIT_BT_TIMINGS(
720, 1920, /* min/max width */
480, 1080, /* min/max height */
27000000, 74250000, /* min/max pixelclock*/
V4L2_DV_BT_STD_CEA861, /* Supported standards */
/* capabilities */
V4L2_DV_BT_CAP_INTERLACED | V4L2_DV_BT_CAP_PROGRESSIVE
)
};
/*
* Supported SDTV standards. This does the same job as skel_timings_cap, but
* for standard TV formats.
*/
#define SKEL_TVNORMS V4L2_STD_ALL
/*
* Interrupt handler: typically interrupts happen after a new frame has been
* captured. It is the job of the handler to remove the new frame from the
* internal list and give it back to the vb2 framework, updating the sequence
* counter, field and timestamp at the same time.
*/
static irqreturn_t skeleton_irq(int irq, void *dev_id)
{
#ifdef TODO
struct skeleton *skel = dev_id;
/* handle interrupt */
/* Once a new frame has been captured, mark it as done like this: */
if (captured_new_frame) {
...
spin_lock(&skel->qlock);
list_del(&new_buf->list);
spin_unlock(&skel->qlock);
v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp);
new_buf->vb.v4l2_buf.sequence = skel->sequence++;
new_buf->vb.v4l2_buf.field = skel->field;
if (skel->format.field == V4L2_FIELD_ALTERNATE) {
if (skel->field == V4L2_FIELD_BOTTOM)
skel->field = V4L2_FIELD_TOP;
else if (skel->field == V4L2_FIELD_TOP)
skel->field = V4L2_FIELD_BOTTOM;
}
vb2_buffer_done(&new_buf->vb, VB2_BUF_STATE_DONE);
}
#endif
return IRQ_HANDLED;
}
/*
* Setup the constraints of the queue: besides setting the number of planes
* per buffer and the size and allocation context of each plane, it also
* checks if sufficient buffers have been allocated. Usually 3 is a good
* minimum number: many DMA engines need a minimum of 2 buffers in the
* queue and you need to have another available for userspace processing.
*/
static int queue_setup(struct vb2_queue *vq, const void *parg,
unsigned int *nbuffers, unsigned int *nplanes,
unsigned int sizes[], void *alloc_ctxs[])
{
const struct v4l2_format *fmt = parg;
struct skeleton *skel = vb2_get_drv_priv(vq);
skel->field = skel->format.field;
if (skel->field == V4L2_FIELD_ALTERNATE) {
/*
* You cannot use read() with FIELD_ALTERNATE since the field
* information (TOP/BOTTOM) cannot be passed back to the user.
*/
if (vb2_fileio_is_active(vq))
return -EINVAL;
skel->field = V4L2_FIELD_TOP;
}
if (vq->num_buffers + *nbuffers < 3)
*nbuffers = 3 - vq->num_buffers;
if (fmt && fmt->fmt.pix.sizeimage < skel->format.sizeimage)
return -EINVAL;
*nplanes = 1;
sizes[0] = fmt ? fmt->fmt.pix.sizeimage : skel->format.sizeimage;
alloc_ctxs[0] = skel->alloc_ctx;
return 0;
}
/*
* Prepare the buffer for queueing to the DMA engine: check and set the
* payload size.
*/
static int buffer_prepare(struct vb2_buffer *vb)
{
struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
unsigned long size = skel->format.sizeimage;
if (vb2_plane_size(vb, 0) < size) {
dev_err(&skel->pdev->dev, "buffer too small (%lu < %lu)\n",
vb2_plane_size(vb, 0), size);
return -EINVAL;
}
vb2_set_plane_payload(vb, 0, size);
return 0;
}
/*
* Queue this buffer to the DMA engine.
*/
static void buffer_queue(struct vb2_buffer *vb)
{
struct skeleton *skel = vb2_get_drv_priv(vb->vb2_queue);
struct skel_buffer *buf = to_skel_buffer(vb);
unsigned long flags;
spin_lock_irqsave(&skel->qlock, flags);
list_add_tail(&buf->list, &skel->buf_list);
/* TODO: Update any DMA pointers if necessary */
spin_unlock_irqrestore(&skel->qlock, flags);
}
static void return_all_buffers(struct skeleton *skel,
enum vb2_buffer_state state)
{
struct skel_buffer *buf, *node;
unsigned long flags;
spin_lock_irqsave(&skel->qlock, flags);
list_for_each_entry_safe(buf, node, &skel->buf_list, list) {
vb2_buffer_done(&buf->vb, state);
list_del(&buf->list);
}
spin_unlock_irqrestore(&skel->qlock, flags);
}
/*
* Start streaming. First check if the minimum number of buffers have been
* queued. If not, then return -ENOBUFS and the vb2 framework will call
* this function again the next time a buffer has been queued until enough
* buffers are available to actually start the DMA engine.
*/
static int start_streaming(struct vb2_queue *vq, unsigned int count)
{
struct skeleton *skel = vb2_get_drv_priv(vq);
int ret = 0;
skel->sequence = 0;
/* TODO: start DMA */
if (ret) {
/*
* In case of an error, return all active buffers to the
* QUEUED state
*/
return_all_buffers(skel, VB2_BUF_STATE_QUEUED);
}
return ret;
}
/*
* Stop the DMA engine. Any remaining buffers in the DMA queue are dequeued
* and passed on to the vb2 framework marked as STATE_ERROR.
*/
static void stop_streaming(struct vb2_queue *vq)
{
struct skeleton *skel = vb2_get_drv_priv(vq);
/* TODO: stop DMA */
/* Release all active buffers */
return_all_buffers(skel, VB2_BUF_STATE_ERROR);
}
/*
* The vb2 queue ops. Note that since q->lock is set we can use the standard
* vb2_ops_wait_prepare/finish helper functions. If q->lock would be NULL,
* then this driver would have to provide these ops.
*/
static struct vb2_ops skel_qops = {
.queue_setup = queue_setup,
.buf_prepare = buffer_prepare,
.buf_queue = buffer_queue,
.start_streaming = start_streaming,
.stop_streaming = stop_streaming,
.wait_prepare = vb2_ops_wait_prepare,
.wait_finish = vb2_ops_wait_finish,
};
/*
* Required ioctl querycap. Note that the version field is prefilled with
* the version of the kernel.
*/
static int skeleton_querycap(struct file *file, void *priv,
struct v4l2_capability *cap)
{
struct skeleton *skel = video_drvdata(file);
strlcpy(cap->driver, KBUILD_MODNAME, sizeof(cap->driver));
strlcpy(cap->card, "V4L2 PCI Skeleton", sizeof(cap->card));
snprintf(cap->bus_info, sizeof(cap->bus_info), "PCI:%s",
pci_name(skel->pdev));
cap->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_READWRITE |
V4L2_CAP_STREAMING;
cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
return 0;
}
/*
* Helper function to check and correct struct v4l2_pix_format. It's used
* not only in VIDIOC_TRY/S_FMT, but also elsewhere if changes to the SDTV
* standard, HDTV timings or the video input would require updating the
* current format.
*/
static void skeleton_fill_pix_format(struct skeleton *skel,
struct v4l2_pix_format *pix)
{
pix->pixelformat = V4L2_PIX_FMT_YUYV;
if (skel->input == 0) {
/* S-Video input */
pix->width = 720;
pix->height = (skel->std & V4L2_STD_525_60) ? 480 : 576;
pix->field = V4L2_FIELD_INTERLACED;
pix->colorspace = V4L2_COLORSPACE_SMPTE170M;
} else {
/* HDMI input */
pix->width = skel->timings.bt.width;
pix->height = skel->timings.bt.height;
if (skel->timings.bt.interlaced) {
pix->field = V4L2_FIELD_ALTERNATE;
pix->height /= 2;
} else {
pix->field = V4L2_FIELD_NONE;
}
pix->colorspace = V4L2_COLORSPACE_REC709;
}
/*
* The YUYV format is four bytes for every two pixels, so bytesperline
* is width * 2.
*/
pix->bytesperline = pix->width * 2;
pix->sizeimage = pix->bytesperline * pix->height;
pix->priv = 0;
}
static int skeleton_try_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct skeleton *skel = video_drvdata(file);
struct v4l2_pix_format *pix = &f->fmt.pix;
/*
* Due to historical reasons providing try_fmt with an unsupported
* pixelformat will return -EINVAL for video receivers. Webcam drivers,
* however, will silently correct the pixelformat. Some video capture
* applications rely on this behavior...
*/
if (pix->pixelformat != V4L2_PIX_FMT_YUYV)
return -EINVAL;
skeleton_fill_pix_format(skel, pix);
return 0;
}
static int skeleton_s_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct skeleton *skel = video_drvdata(file);
int ret;
ret = skeleton_try_fmt_vid_cap(file, priv, f);
if (ret)
return ret;
/*
* It is not allowed to change the format while buffers for use with
* streaming have already been allocated.
*/
if (vb2_is_busy(&skel->queue))
return -EBUSY;
/* TODO: change format */
skel->format = f->fmt.pix;
return 0;
}
static int skeleton_g_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_format *f)
{
struct skeleton *skel = video_drvdata(file);
f->fmt.pix = skel->format;
return 0;
}
static int skeleton_enum_fmt_vid_cap(struct file *file, void *priv,
struct v4l2_fmtdesc *f)
{
if (f->index != 0)
return -EINVAL;
f->pixelformat = V4L2_PIX_FMT_YUYV;
return 0;
}
static int skeleton_s_std(struct file *file, void *priv, v4l2_std_id std)
{
struct skeleton *skel = video_drvdata(file);
/* S_STD is not supported on the HDMI input */
if (skel->input)
return -ENODATA;
/*
* No change, so just return. Some applications call S_STD again after
* the buffers for streaming have been set up, so we have to allow for
* this behavior.
*/
if (std == skel->std)
return 0;
/*
* Changing the standard implies a format change, which is not allowed
* while buffers for use with streaming have already been allocated.
*/
if (vb2_is_busy(&skel->queue))
return -EBUSY;
/* TODO: handle changing std */
skel->std = std;
/* Update the internal format */
skeleton_fill_pix_format(skel, &skel->format);
return 0;
}
static int skeleton_g_std(struct file *file, void *priv, v4l2_std_id *std)
{
struct skeleton *skel = video_drvdata(file);
/* G_STD is not supported on the HDMI input */
if (skel->input)
return -ENODATA;
*std = skel->std;
return 0;
}
/*
* Query the current standard as seen by the hardware. This function shall
* never actually change the standard, it just detects and reports.
* The framework will initially set *std to tvnorms (i.e. the set of
* supported standards by this input), and this function should just AND
* this value. If there is no signal, then *std should be set to 0.
*/
static int skeleton_querystd(struct file *file, void *priv, v4l2_std_id *std)
{
struct skeleton *skel = video_drvdata(file);
/* QUERY_STD is not supported on the HDMI input */
if (skel->input)
return -ENODATA;
#ifdef TODO
/*
* Query currently seen standard. Initial value of *std is
* V4L2_STD_ALL. This function should look something like this:
*/
get_signal_info();
if (no_signal) {
*std = 0;
return 0;
}
/* Use signal information to reduce the number of possible standards */
if (signal_has_525_lines)
*std &= V4L2_STD_525_60;
else
*std &= V4L2_STD_625_50;
#endif
return 0;
}
static int skeleton_s_dv_timings(struct file *file, void *_fh,
struct v4l2_dv_timings *timings)
{
struct skeleton *skel = video_drvdata(file);
/* S_DV_TIMINGS is not supported on the S-Video input */
if (skel->input == 0)
return -ENODATA;
/* Quick sanity check */
if (!v4l2_valid_dv_timings(timings, &skel_timings_cap, NULL, NULL))
return -EINVAL;
/* Check if the timings are part of the CEA-861 timings. */
if (!v4l2_find_dv_timings_cap(timings, &skel_timings_cap,
0, NULL, NULL))
return -EINVAL;
/* Return 0 if the new timings are the same as the current timings. */
if (v4l2_match_dv_timings(timings, &skel->timings, 0))
return 0;
/*
* Changing the timings implies a format change, which is not allowed
* while buffers for use with streaming have already been allocated.
*/
if (vb2_is_busy(&skel->queue))
return -EBUSY;
/* TODO: Configure new timings */
/* Save timings */
skel->timings = *timings;
/* Update the internal format */
skeleton_fill_pix_format(skel, &skel->format);
return 0;
}
static int skeleton_g_dv_timings(struct file *file, void *_fh,
struct v4l2_dv_timings *timings)
{
struct skeleton *skel = video_drvdata(file);
/* G_DV_TIMINGS is not supported on the S-Video input */
if (skel->input == 0)
return -ENODATA;
*timings = skel->timings;
return 0;
}
static int skeleton_enum_dv_timings(struct file *file, void *_fh,
struct v4l2_enum_dv_timings *timings)
{
struct skeleton *skel = video_drvdata(file);
/* ENUM_DV_TIMINGS is not supported on the S-Video input */
if (skel->input == 0)
return -ENODATA;
return v4l2_enum_dv_timings_cap(timings, &skel_timings_cap,
NULL, NULL);
}
/*
* Query the current timings as seen by the hardware. This function shall
* never actually change the timings, it just detects and reports.
* If no signal is detected, then return -ENOLINK. If the hardware cannot
* lock to the signal, then return -ENOLCK. If the signal is out of range
* of the capabilities of the system (e.g., it is possible that the receiver
* can lock but that the DMA engine it is connected to cannot handle
* pixelclocks above a certain frequency), then -ERANGE is returned.
*/
static int skeleton_query_dv_timings(struct file *file, void *_fh,
struct v4l2_dv_timings *timings)
{
struct skeleton *skel = video_drvdata(file);
/* QUERY_DV_TIMINGS is not supported on the S-Video input */
if (skel->input == 0)
return -ENODATA;
#ifdef TODO
/*
* Query currently seen timings. This function should look
* something like this:
*/
detect_timings();
if (no_signal)
return -ENOLINK;
if (cannot_lock_to_signal)
return -ENOLCK;
if (signal_out_of_range_of_capabilities)
return -ERANGE;
/* Useful for debugging */
v4l2_print_dv_timings(skel->v4l2_dev.name, "query_dv_timings:",
timings, true);
#endif
return 0;
}
static int skeleton_dv_timings_cap(struct file *file, void *fh,
struct v4l2_dv_timings_cap *cap)
{
struct skeleton *skel = video_drvdata(file);
/* DV_TIMINGS_CAP is not supported on the S-Video input */
if (skel->input == 0)
return -ENODATA;
*cap = skel_timings_cap;
return 0;
}
static int skeleton_enum_input(struct file *file, void *priv,
struct v4l2_input *i)
{
if (i->index > 1)
return -EINVAL;
i->type = V4L2_INPUT_TYPE_CAMERA;
if (i->index == 0) {
i->std = SKEL_TVNORMS;
strlcpy(i->name, "S-Video", sizeof(i->name));
i->capabilities = V4L2_IN_CAP_STD;
} else {
i->std = 0;
strlcpy(i->name, "HDMI", sizeof(i->name));
i->capabilities = V4L2_IN_CAP_DV_TIMINGS;
}
return 0;
}
static int skeleton_s_input(struct file *file, void *priv, unsigned int i)
{
struct skeleton *skel = video_drvdata(file);
if (i > 1)
return -EINVAL;
/*
* Changing the input implies a format change, which is not allowed
* while buffers for use with streaming have already been allocated.
*/
if (vb2_is_busy(&skel->queue))
return -EBUSY;
skel->input = i;
/*
* Update tvnorms. The tvnorms value is used by the core to implement
* VIDIOC_ENUMSTD so it has to be correct. If tvnorms == 0, then
* ENUMSTD will return -ENODATA.
*/
skel->vdev.tvnorms = i ? 0 : SKEL_TVNORMS;
/* Update the internal format */
skeleton_fill_pix_format(skel, &skel->format);
return 0;
}
static int skeleton_g_input(struct file *file, void *priv, unsigned int *i)
{
struct skeleton *skel = video_drvdata(file);
*i = skel->input;
return 0;
}
/* The control handler. */
static int skeleton_s_ctrl(struct v4l2_ctrl *ctrl)
{
/*struct skeleton *skel =
container_of(ctrl->handler, struct skeleton, ctrl_handler);*/
switch (ctrl->id) {
case V4L2_CID_BRIGHTNESS:
/* TODO: set brightness to ctrl->val */
break;
case V4L2_CID_CONTRAST:
/* TODO: set contrast to ctrl->val */
break;
case V4L2_CID_SATURATION:
/* TODO: set saturation to ctrl->val */
break;
case V4L2_CID_HUE:
/* TODO: set hue to ctrl->val */
break;
default:
return -EINVAL;
}
return 0;
}
/* ------------------------------------------------------------------
File operations for the device
------------------------------------------------------------------*/
static const struct v4l2_ctrl_ops skel_ctrl_ops = {
.s_ctrl = skeleton_s_ctrl,
};
/*
* The set of all supported ioctls. Note that all the streaming ioctls
* use the vb2 helper functions that take care of all the locking and
* that also do ownership tracking (i.e. only the filehandle that requested
* the buffers can call the streaming ioctls, all other filehandles will
* receive -EBUSY if they attempt to call the same streaming ioctls).
*
* The last three ioctls also use standard helper functions: these implement
* standard behavior for drivers with controls.
*/
static const struct v4l2_ioctl_ops skel_ioctl_ops = {
.vidioc_querycap = skeleton_querycap,
.vidioc_try_fmt_vid_cap = skeleton_try_fmt_vid_cap,
.vidioc_s_fmt_vid_cap = skeleton_s_fmt_vid_cap,
.vidioc_g_fmt_vid_cap = skeleton_g_fmt_vid_cap,
.vidioc_enum_fmt_vid_cap = skeleton_enum_fmt_vid_cap,
.vidioc_g_std = skeleton_g_std,
.vidioc_s_std = skeleton_s_std,
.vidioc_querystd = skeleton_querystd,
.vidioc_s_dv_timings = skeleton_s_dv_timings,
.vidioc_g_dv_timings = skeleton_g_dv_timings,
.vidioc_enum_dv_timings = skeleton_enum_dv_timings,
.vidioc_query_dv_timings = skeleton_query_dv_timings,
.vidioc_dv_timings_cap = skeleton_dv_timings_cap,
.vidioc_enum_input = skeleton_enum_input,
.vidioc_g_input = skeleton_g_input,
.vidioc_s_input = skeleton_s_input,
.vidioc_reqbufs = vb2_ioctl_reqbufs,
.vidioc_create_bufs = vb2_ioctl_create_bufs,
.vidioc_querybuf = vb2_ioctl_querybuf,
.vidioc_qbuf = vb2_ioctl_qbuf,
.vidioc_dqbuf = vb2_ioctl_dqbuf,
.vidioc_expbuf = vb2_ioctl_expbuf,
.vidioc_streamon = vb2_ioctl_streamon,
.vidioc_streamoff = vb2_ioctl_streamoff,
.vidioc_log_status = v4l2_ctrl_log_status,
.vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
};
/*
* The set of file operations. Note that all these ops are standard core
* helper functions.
*/
static const struct v4l2_file_operations skel_fops = {
.owner = THIS_MODULE,
.open = v4l2_fh_open,
.release = vb2_fop_release,
.unlocked_ioctl = video_ioctl2,
.read = vb2_fop_read,
.mmap = vb2_fop_mmap,
.poll = vb2_fop_poll,
};
/*
* The initial setup of this device instance. Note that the initial state of
* the driver should be complete. So the initial format, standard, timings
* and video input should all be initialized to some reasonable value.
*/
static int skeleton_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
/* The initial timings are chosen to be 720p60. */
static const struct v4l2_dv_timings timings_def =
V4L2_DV_BT_CEA_1280X720P60;
struct skeleton *skel;
struct video_device *vdev;
struct v4l2_ctrl_handler *hdl;
struct vb2_queue *q;
int ret;
/* Enable PCI */
ret = pci_enable_device(pdev);
if (ret)
return ret;
ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
if (ret) {
dev_err(&pdev->dev, "no suitable DMA available.\n");
goto disable_pci;
}
/* Allocate a new instance */
skel = devm_kzalloc(&pdev->dev, sizeof(struct skeleton), GFP_KERNEL);
if (!skel)
return -ENOMEM;
/* Allocate the interrupt */
ret = devm_request_irq(&pdev->dev, pdev->irq,
skeleton_irq, 0, KBUILD_MODNAME, skel);
if (ret) {
dev_err(&pdev->dev, "request_irq failed\n");
goto disable_pci;
}
skel->pdev = pdev;
/* Fill in the initial format-related settings */
skel->timings = timings_def;
skel->std = V4L2_STD_625_50;
skeleton_fill_pix_format(skel, &skel->format);
/* Initialize the top-level structure */
ret = v4l2_device_register(&pdev->dev, &skel->v4l2_dev);
if (ret)
goto disable_pci;
mutex_init(&skel->lock);
/* Add the controls */
hdl = &skel->ctrl_handler;
v4l2_ctrl_handler_init(hdl, 4);
v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
V4L2_CID_BRIGHTNESS, 0, 255, 1, 127);
v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
V4L2_CID_CONTRAST, 0, 255, 1, 16);
v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
V4L2_CID_SATURATION, 0, 255, 1, 127);
v4l2_ctrl_new_std(hdl, &skel_ctrl_ops,
V4L2_CID_HUE, -128, 127, 1, 0);
if (hdl->error) {
ret = hdl->error;
goto free_hdl;
}
skel->v4l2_dev.ctrl_handler = hdl;
/* Initialize the vb2 queue */
q = &skel->queue;
q->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
q->io_modes = VB2_MMAP | VB2_DMABUF | VB2_READ;
q->drv_priv = skel;
q->buf_struct_size = sizeof(struct skel_buffer);
q->ops = &skel_qops;
q->mem_ops = &vb2_dma_contig_memops;
q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
/*
* Assume that this DMA engine needs to have at least two buffers
* available before it can be started. The start_streaming() op
* won't be called until at least this many buffers are queued up.
*/
q->min_buffers_needed = 2;
/*
* The serialization lock for the streaming ioctls. This is the same
* as the main serialization lock, but if some of the non-streaming
* ioctls could take a long time to execute, then you might want to
* have a different lock here to prevent VIDIOC_DQBUF from being
* blocked while waiting for another action to finish. This is
* generally not needed for PCI devices, but USB devices usually do
* want a separate lock here.
*/
q->lock = &skel->lock;
/*
* Since this driver can only do 32-bit DMA we must make sure that
* the vb2 core will allocate the buffers in 32-bit DMA memory.
*/
q->gfp_flags = GFP_DMA32;
ret = vb2_queue_init(q);
if (ret)
goto free_hdl;
skel->alloc_ctx = vb2_dma_contig_init_ctx(&pdev->dev);
if (IS_ERR(skel->alloc_ctx)) {
dev_err(&pdev->dev, "Can't allocate buffer context");
ret = PTR_ERR(skel->alloc_ctx);
goto free_hdl;
}
INIT_LIST_HEAD(&skel->buf_list);
spin_lock_init(&skel->qlock);
/* Initialize the video_device structure */
vdev = &skel->vdev;
strlcpy(vdev->name, KBUILD_MODNAME, sizeof(vdev->name));
/*
* There is nothing to clean up, so release is set to an empty release
* function. The release callback must be non-NULL.
*/
vdev->release = video_device_release_empty;
vdev->fops = &skel_fops,
vdev->ioctl_ops = &skel_ioctl_ops,
/*
* The main serialization lock. All ioctls are serialized by this
* lock. Exception: if q->lock is set, then the streaming ioctls
* are serialized by that separate lock.
*/
vdev->lock = &skel->lock;
vdev->queue = q;
vdev->v4l2_dev = &skel->v4l2_dev;
/* Supported SDTV standards, if any */
vdev->tvnorms = SKEL_TVNORMS;
video_set_drvdata(vdev, skel);
ret = video_register_device(vdev, VFL_TYPE_GRABBER, -1);
if (ret)
goto free_ctx;
dev_info(&pdev->dev, "V4L2 PCI Skeleton Driver loaded\n");
return 0;
free_ctx:
vb2_dma_contig_cleanup_ctx(skel->alloc_ctx);
free_hdl:
v4l2_ctrl_handler_free(&skel->ctrl_handler);
v4l2_device_unregister(&skel->v4l2_dev);
disable_pci:
pci_disable_device(pdev);
return ret;
}
static void skeleton_remove(struct pci_dev *pdev)
{
struct v4l2_device *v4l2_dev = pci_get_drvdata(pdev);
struct skeleton *skel = container_of(v4l2_dev, struct skeleton, v4l2_dev);
video_unregister_device(&skel->vdev);
v4l2_ctrl_handler_free(&skel->ctrl_handler);
vb2_dma_contig_cleanup_ctx(skel->alloc_ctx);
v4l2_device_unregister(&skel->v4l2_dev);
pci_disable_device(skel->pdev);
}
static struct pci_driver skeleton_driver = {
.name = KBUILD_MODNAME,
.probe = skeleton_probe,
.remove = skeleton_remove,
.id_table = skeleton_pci_tbl,
};
module_pci_driver(skeleton_driver);