Hi Hans, I don't like very much the idea of adding skeleton drivers inside drivers/media. We have there already enough drivers to pollute it with more skeleton ones. I think that the best is to put it on some other place. Eventually, we could put it at Documentation: $ ls Documentation/*/*.c Documentation/accounting/getdelays.c Documentation/prctl/disable-tsc-ctxt-sw-stress-test.c Documentation/auxdisplay/cfag12864b-example.c Documentation/prctl/disable-tsc-on-off-stress-test.c Documentation/blackfin/gptimers-example.c Documentation/prctl/disable-tsc-test.c Documentation/connector/cn_test.c Documentation/ptp/testptp.c Documentation/connector/ucon.c Documentation/spi/spidev_fdx.c Documentation/filesystems/dnotify_test.c Documentation/spi/spidev_test.c Documentation/ia64/aliasing-test.c Documentation/timers/hpet_example.c Documentation/laptops/dslm.c Documentation/vDSO/parse_vdso.c Documentation/laptops/hpfall.c Documentation/vDSO/vdso_test.c Some drivers there, like: Documentation/blackfin/gptimers-example.c Are clearly skeleton drivers. Regards, Mauro Em Sun, 09 Mar 2014 17:07:42 +0100 Hans Verkuil <hverkuil@xxxxxxxxx> escreveu: > This patch is almost identical to the earlier RFC version: > > https://patchwork.linuxtv.org/patch/21780/ > > The only changes are that it has been rebased to the latest vb2 changes so it > can take advantage of the min_buffers_needed field and it adds code to requeue > buffers in case of a failure when starting the DMA. > > This example driver uses all the latest frameworks and can serve as a > starting point for a new V4L2 PCI driver. > > Originally written for a presentation on how to use V4L2 frameworks > during FOSDEM 2014. > > Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx> > --- > drivers/media/pci/Kconfig | 1 + > drivers/media/pci/Makefile | 2 + > drivers/media/pci/skeleton/Kconfig | 11 + > drivers/media/pci/skeleton/Makefile | 1 + > drivers/media/pci/skeleton/v4l2-pci-skeleton.c | 912 +++++++++++++++++++++++++ > 5 files changed, 927 insertions(+) > create mode 100644 drivers/media/pci/skeleton/Kconfig > create mode 100644 drivers/media/pci/skeleton/Makefile > create mode 100644 drivers/media/pci/skeleton/v4l2-pci-skeleton.c > > diff --git a/drivers/media/pci/Kconfig b/drivers/media/pci/Kconfig > index 53196f1..1717a91 100644 > --- a/drivers/media/pci/Kconfig > +++ b/drivers/media/pci/Kconfig > @@ -19,6 +19,7 @@ if MEDIA_ANALOG_TV_SUPPORT > source "drivers/media/pci/ivtv/Kconfig" > source "drivers/media/pci/zoran/Kconfig" > source "drivers/media/pci/saa7146/Kconfig" > +source "drivers/media/pci/skeleton/Kconfig" > endif > > if MEDIA_ANALOG_TV_SUPPORT || MEDIA_DIGITAL_TV_SUPPORT > diff --git a/drivers/media/pci/Makefile b/drivers/media/pci/Makefile > index 35cc578..ec08f46 100644 > --- a/drivers/media/pci/Makefile > +++ b/drivers/media/pci/Makefile > @@ -11,11 +11,13 @@ obj-y += ttpci/ \ > ngene/ \ > ddbridge/ \ > b2c2/ \ > + skeleton/ \ > saa7146/ > > obj-$(CONFIG_VIDEO_IVTV) += ivtv/ > obj-$(CONFIG_VIDEO_ZORAN) += zoran/ > obj-$(CONFIG_VIDEO_CX18) += cx18/ > +obj-$(CONFIG_VIDEO_PCI_SKELETON) += skeleton/ > obj-$(CONFIG_VIDEO_CX23885) += cx23885/ > obj-$(CONFIG_VIDEO_CX25821) += cx25821/ > obj-$(CONFIG_VIDEO_CX88) += cx88/ > diff --git a/drivers/media/pci/skeleton/Kconfig b/drivers/media/pci/skeleton/Kconfig > new file mode 100644 > index 0000000..e58b150 > --- /dev/null > +++ b/drivers/media/pci/skeleton/Kconfig > @@ -0,0 +1,11 @@ > +config VIDEO_PCI_SKELETON > + tristate "V4L2 PCI Skeleton Driver" > + select VIDEOBUF2_DMA_CONTIG > + depends on PCI && VIDEO_V4L2 > + default n > + help > + Say Y for support for this PCI Skeleton Driver capture > + device. > + > + To compile this driver as a module, choose M here: the > + module will be called v4l2-pci-skeleton. > diff --git a/drivers/media/pci/skeleton/Makefile b/drivers/media/pci/skeleton/Makefile > new file mode 100644 > index 0000000..3a935ca > --- /dev/null > +++ b/drivers/media/pci/skeleton/Makefile > @@ -0,0 +1 @@ > +obj-$(CONFIG_VIDEO_PCI_SKELETON) += v4l2-pci-skeleton.o > diff --git a/drivers/media/pci/skeleton/v4l2-pci-skeleton.c b/drivers/media/pci/skeleton/v4l2-pci-skeleton.c > new file mode 100644 > index 0000000..53d2d7a > --- /dev/null > +++ b/drivers/media/pci/skeleton/v4l2-pci-skeleton.c > @@ -0,0 +1,912 @@ > +/* > + * 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-dma-contig.h> > + > +MODULE_DESCRIPTION("V4L2 PCI Skeleton Driver"); > +MODULE_AUTHOR("Hans Verkuil"); > +MODULE_LICENSE("GPL v2"); > +MODULE_DEVICE_TABLE(pci, skeleton_pci_tbl); > + > +/** > + * 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 int 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, } > +}; > + > +/* > + * 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 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); > + new_buf->vb.v4l2_buf.sequence = skel->sequence++; > + v4l2_get_timestamp(&new_buf->vb.v4l2_buf.timestamp); > + 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 struct v4l2_format *fmt, > + unsigned int *nbuffers, unsigned int *nplanes, > + unsigned int sizes[], void *alloc_ctxs[]) > +{ > + struct skeleton *skel = vb2_get_drv_priv(vq); > + > + 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 and fill in the field. Note: if the format's field is > + * V4L2_FIELD_ALTERNATE, then vb->v4l2_buf.field should be set in the > + * interrupt handler since that's usually where you know if the TOP or > + * BOTTOM field has been captured. > + */ > +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); > + vb->v4l2_buf.field = skel->format.field; > + 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 int 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); > + return 0; > +} > + > +/* > + * 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_INTERLACED; > + 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; > + > + strlcpy(f->description, "4:2:2, packed, YUYV", sizeof(f->description)); > + f->pixelformat = V4L2_PIX_FMT_YUYV; > + f->flags = 0; > + 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_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; > + /* If this bit is set, then the v4l2 core will provide the support > + * for the VIDIOC_G/S_PRIORITY ioctls. This flag will eventually > + * go away once all drivers have been converted to use struct v4l2_fh. > + */ > + set_bit(V4L2_FL_USE_FH_PRIO, &vdev->flags); > + 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); -- Regards, Mauro -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
