foo

diff --git a/vdummy.c b/vdummy.c
index 9848db6..d107e59 100644 (file)
--- a/vdummy.c
+++ b/vdummy.c
@@ -3,6 +3,8 @@
 #include <linux/mutex.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
+#include <linux/hrtimer.h>
+#include <linux/ktime.h>
 #include <asm/uaccess.h>
 #include <linux/videodev2.h>
 #include <media/videobuf2-v4l2.h>
@@ -25,6 +27,7 @@ static int ioctl_querycap(struct file *file, void *fh, struct v4l2_capability *c
 static int ioctl_enum_fmt(struct file *file, void *fh, struct v4l2_fmtdesc *fdesc);
 static int ioctl_get_fmt(struct file *file, void *fh, struct v4l2_format *fmt);
 static int ioctl_set_fmt(struct file *file, void *fh, struct v4l2_format *fmt);
+static int ioctl_try_fmt(struct file *file, void *fh, struct v4l2_format *fmt);
 static int ioctl_get_parm(struct file *file, void *fh, struct v4l2_streamparm *fmt);
 static int ioctl_set_parm(struct file *file, void *fh, struct v4l2_streamparm *fmt);
 static int ioctl_queryctl(struct file *file, void *fh, struct v4l2_queryctrl *ctl);
@@ -39,6 +42,7 @@ static void stop_streaming(struct vb2_queue *vbq);
 
 static int update_frame(int xsz, int ysz);
 static int gen_frame(void);
+enum hrtimer_restart timer_func(struct hrtimer *timer);
 
 
 module_init(init);
@@ -65,6 +69,8 @@ static spinlock_t blist_lock;
 static struct buffer *buflist, *buflist_tail;
 static int seqno;
 
+static int framerate = 1;
+static struct hrtimer timer;
 
 static int init(void)
 {
@@ -92,7 +98,7 @@ static int init(void)
        vbq.ops = &vbops;
        vbq.mem_ops = &vb2_vmalloc_memops;
        vbq.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
-       vbq.min_buffers_needed = 1;
+       vbq.min_buffers_needed = 2;
        vbq.lock = &mutex;
        vbq.gfp_flags = GFP_KERNEL;
 
@@ -128,6 +134,7 @@ static int init(void)
        iops.vidioc_enum_fmt_vid_cap = ioctl_enum_fmt;
        iops.vidioc_g_fmt_vid_cap = ioctl_get_fmt;
        iops.vidioc_s_fmt_vid_cap = ioctl_set_fmt;
+       iops.vidioc_try_fmt_vid_cap = ioctl_try_fmt;
        iops.vidioc_g_parm = ioctl_get_parm;
        iops.vidioc_s_parm = ioctl_set_parm;
        iops.vidioc_queryctrl = ioctl_queryctl;
@@ -150,6 +157,9 @@ static int init(void)
                return res;
        }
 
+       hrtimer_init(&timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+       timer.function = timer_func;
+
        if((res = update_frame(640, 480)) != 0) {
                video_unregister_device(vdev);
                v4l2_device_unregister(&v4l2_dev);
@@ -222,6 +232,28 @@ static int ioctl_set_fmt(struct file *file, void *fh, struct v4l2_format *fmt)
        return ioctl_get_fmt(file, fh, fmt);
 }
 
+static int ioctl_try_fmt(struct file *file, void *fh, struct v4l2_format *fmt)
+{
+       if(fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+               return -EINVAL;
+       }
+       if(fmt->fmt.pix.width <= 0)
+               fmt->fmt.pix.width = width;
+       if(fmt->fmt.pix.height <= 0)
+               fmt->fmt.pix.height = height;
+       fmt->fmt.pix.pixelformat = V4L2_PIX_FMT_RGB24;
+       fmt->fmt.pix.field = V4L2_FIELD_NONE;
+       fmt->fmt.pix.bytesperline = 0;
+       fmt->fmt.pix.sizeimage = frame_size;
+       fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
+       fmt->fmt.pix.priv = 0;
+       fmt->fmt.pix.flags = 0;
+       fmt->fmt.pix.ycbcr_enc = 0;
+       fmt->fmt.pix.quantization = V4L2_QUANTIZATION_FULL_RANGE;
+       fmt->fmt.pix.xfer_func = V4L2_XFER_FUNC_NONE;
+       return 0;
+}
+
 static int ioctl_get_parm(struct file *file, void *fh, struct v4l2_streamparm *parm)
 {
        if(parm->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) {
@@ -230,7 +262,7 @@ static int ioctl_get_parm(struct file *file, void *fh, struct v4l2_streamparm *p
        parm->parm.capture.capability = 0;
        parm->parm.capture.capturemode = 0;
        parm->parm.capture.timeperframe.numerator = 1;
-       parm->parm.capture.timeperframe.denominator = 30;
+       parm->parm.capture.timeperframe.denominator = framerate;
        parm->parm.capture.extendedmode = 0;
        parm->parm.capture.readbuffers = 1;
        return 0;
@@ -238,9 +270,14 @@ static int ioctl_get_parm(struct file *file, void *fh, struct v4l2_streamparm *p
 
 static int ioctl_set_parm(struct file *file, void *fh, struct v4l2_streamparm *parm)
 {
+       int new_framerate;
        if(parm->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) {
                return -EINVAL;
        }
+
+       new_framerate = parm->parm.capture.timeperframe.denominator / parm->parm.capture.timeperframe.numerator;
+       framerate = new_framerate < 1 ? 1 : (new_framerate > 60 ? 60 : new_framerate);
+
        return ioctl_get_parm(file, fh, parm);
 }
 
@@ -300,15 +337,26 @@ static void clear_queue(enum vb2_buffer_state st)
 
 static int start_streaming(struct vb2_queue *vbq, unsigned int count)
 {
+       ktime_t frame_interval;
+
        streaming = 1;
        seqno = 0;
 
-       gen_frame();
+       /* calculate frame interval in nanoseconds */
+       if(framerate <= 1) {
+               frame_interval = ktime_set(1, 0);
+       } else {
+               frame_interval = ktime_set(0, 1000000000ul / (unsigned long)framerate);
+       }
+
+       hrtimer_start(&timer, frame_interval, HRTIMER_MODE_REL);
        return 0;
 }
 
 static void stop_streaming(struct vb2_queue *vbq)
 {
+       while(hrtimer_try_to_cancel(&timer) == -1);
+
        streaming = 0;
        clear_queue(VB2_BUF_STATE_ERROR);
 }
@@ -362,6 +410,8 @@ static int gen_frame(void)
        spin_unlock(&blist_lock);
 
        if(buf) {
+               printk(KERN_INFO "vdummy: copying frame: %d\n", seqno);
+
                memcpy(vb2_plane_vaddr(&buf->vb.vb2_buf, 0), frame, frame_size);
 
                buf->vb.vb2_buf.timestamp = ktime_get_ns();
@@ -370,6 +420,11 @@ static int gen_frame(void)
                vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
                vb2_set_plane_payload(&buf->vb.vb2_buf, 0, frame_size);
        }
-
        return 0;
 }
+
+enum hrtimer_restart timer_func(struct hrtimer *timer)
+{
+       gen_frame();
+       return streaming ? HRTIMER_RESTART : HRTIMER_NORESTART;
+}