Media interface implementation

meson.build

@@ -37,7 +37,8 @@ configure_file(output : 'config.h', configuration : cdata)
 
 # Plugin 1
 plugin_sources = [
-  'pinesrcbin.c'
+  'pinesrcbin.c',
+  'utility.c'
   ]
 
 gstpluginexample = library('gstpinesrcbin',

pinesrcbin.c

@@ -14,6 +14,9 @@
 #include <linux/media.h>
 #include <linux/videodev2.h>
 
+#include "utility.h"
+#include "pinesrcbin.h"
+
 #define GST_TYPE_PINESRCBIN	(gst_pinesrcbin_get_type())
 #define GST_PINESRCBIN(obj) \
   (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_PINESRCBIN, GstPineSrcBin))
@@ -32,39 +35,9 @@ enum
   PROP_0,
   PROP_CAPS,
   PROP_SYNC,
+  PROP_NUM_BUFFERS,
 };
 
-struct device_data;
-typedef struct _GstPineSrcBin
-{
-  GstBin parent;
-
-  GList *media_list;
-  struct device_data *media_if;
-  /* configuration for subclasses */
-  const gchar *media_klass;     /* Audio/Video/... */
-  GstElementFlags flag;         /* GST_ELEMENT_FLAG_{SINK/SOURCE} */
-
-  /* explicit pointers to stuff used */
-  GstPad *pad;
-  GstCaps *filter_caps;
-  gboolean sync;
-
-  /* < private > */
-  GstElement *kid;
-  gboolean has_sync;
-  const gchar *type_klass;      /* Source/Sink */
-  const gchar *media_klass_lc, *type_klass_lc;  /* lower case versions */
-
-  const struct media_v2_entity *v4l2entity;
-  const struct media_v2_pad *v4l2pad;
-  const struct media_v2_interface *v4l2interface;
-  char devnode_path[260];
-  int fd;
-  gboolean autofocus;
-  int gain_ctrl;
-  int gain_max;
-} GstPineSrcBin;
 
 typedef struct _GstPineSrcBinClass
 {
@@ -79,23 +52,16 @@ typedef struct _GstPineSrcBinClass
 
 G_DEFINE_TYPE (GstPineSrcBin, gst_pinesrcbin, GST_TYPE_BIN);
 
-static int
-xioctl (int fd, int request, void *arg)
-{
-  int r;
-  do {
-    r = ioctl (fd, request, arg);
-  } while (r == -1 && errno == EINTR);
-  return r;
-}
 
 static void
 gst_pinesrcbin_clear_kid (GstPineSrcBin * self)
 {
   if (self->kid) {
     gst_element_set_state (self->kid, GST_STATE_NULL);
-    gst_bin_remove (GST_BIN (self), self->kid);
+    gst_element_set_state (self->filter, GST_STATE_NULL);
+    gst_bin_remove_many (GST_BIN (self), self->kid, self->filter, NULL);
     self->kid = NULL;
+    self->filter = NULL;
   }
 }
 
@@ -130,10 +96,9 @@ gst_pinesrcbin_create_fake_element (GstPineSrcBin * self)
 static gboolean
 gst_pinesrcbin_attach_ghost_pad (GstPineSrcBin * self)
 {
-  GstPad *target = gst_element_get_static_pad (self->kid, self->type_klass_lc);
+  GstPad *target = gst_element_get_static_pad (self->filter, self->type_klass_lc);
   gboolean res = gst_ghost_pad_set_target (GST_GHOST_PAD (self->pad), target);
   gst_object_unref (target);
-
   return res;
 }
 
@@ -143,8 +108,13 @@ gst_pinesrcbin_reset (GstPineSrcBin * self)
   gst_pinesrcbin_clear_kid (self);
 
   /* placeholder element */
+  // self->kid = gst_pinesrcbin_create_fake_element (self);
   self->kid = gst_pinesrcbin_create_fake_element (self);
-  gst_bin_add (GST_BIN (self), self->kid);
+  self->filter = gst_element_factory_make ("capsfilter", NULL);
+  g_object_set (self->filter, "sync", self->sync, NULL);
+  g_object_set (self->filter, "caps", self->filter_caps, NULL);
+  gst_bin_add_many (GST_BIN (self), self->kid, self->filter, NULL);
+  gst_element_link(self->kid, self->filter);
 
   gst_pinesrcbin_attach_ghost_pad (self);
 }
@@ -153,11 +123,23 @@ static GstStaticCaps raw_video_caps = GST_STATIC_CAPS ("video/x-raw");
 static void
 gst_pinesrcbin_constructed (GObject * object)
 {
+  int width, height;
+  const char *format;
+  struct v4l2_fract interval;
   GstPineSrcBin *self = GST_PINESRCBIN (object);
   if (G_OBJECT_CLASS (parent_class)->constructed)
     G_OBJECT_CLASS (parent_class)->constructed (object);
   self->type_klass = (self->flag == GST_ELEMENT_FLAG_SINK) ? "Sink" : "Source";
   self->filter_caps = gst_static_caps_get (&raw_video_caps);
+  gst_pinesrcbin_get_gst_caps_data("rear", &width, &height, &format, &interval);
+  self->filter_caps = gst_caps_new_simple ("video/x-raw",
+     "format", G_TYPE_STRING, format,
+     /* we "flip" interval to get frame rate */
+     "framerate", GST_TYPE_FRACTION, interval.denominator, interval.numerator,
+     "width", G_TYPE_INT, width,
+     "height", G_TYPE_INT, height,
+     NULL);
+
   self->type_klass_lc = (self->flag == GST_ELEMENT_FLAG_SINK) ? "sink" : "src";
   self->media_klass_lc = "video";
   self->pad = gst_ghost_pad_new_no_target (self->type_klass_lc,
@@ -200,6 +182,11 @@ gst_pinesrcbin_set_property (GObject * object, guint prop_id,
       if (self->kid && self->has_sync)
         g_object_set_property (G_OBJECT (self->kid), pspec->name, value);
       break;
+    case PROP_NUM_BUFFERS:
+      self->num_buffers = g_value_get_int (value);
+      if (self->kid)
+        g_object_set_property (G_OBJECT (self->kid), pspec->name, value);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -219,6 +206,9 @@ gst_pinesrcbin_get_property (GObject * object, guint prop_id,
     case PROP_SYNC:
       g_value_set_boolean (value, self->sync);
       break;
+    case PROP_NUM_BUFFERS:
+      g_value_set_int (value, self->num_buffers);
+      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
       break;
@@ -228,37 +218,59 @@ gst_pinesrcbin_get_property (GObject * object, guint prop_id,
 static gboolean
 gst_pinesrcbin_detect (GstPineSrcBin * self)
 {
-  GstElement *kid;
+  GstElement *kid, *filter;
+  GstPad *target;
   GstPineSrcBinClass *klass = GST_PINESRCBIN_GET_CLASS (self);
 
   gst_pinesrcbin_clear_kid (self);
 
+  GST_DEBUG_OBJECT (self, "Creating v4l2src element");
   kid = gst_element_factory_make ("v4l2src", NULL);
+  GST_DEBUG_OBJECT (self, "Creating capsfilter element");
+  filter = gst_element_factory_make ("capsfilter", "capsfilter1");
 #if 0
   /* find element */
   GST_DEBUG_OBJECT (self, "Creating new kid");
   if (!(kid = gst_pinesrcbin_find_best (self)))
 #endif
-    if (!kid)
+    if (!kid || !filter)
       goto no_sink;
 
+  GST_DEBUG_OBJECT (self, "Setting fixed pad caps");
+  target = gst_element_get_static_pad (kid, self->type_klass_lc);
+  gst_pad_use_fixed_caps (target);
+  gst_pad_set_caps(target, self->filter_caps);
+
+  GST_DEBUG_OBJECT (self, "Setting default properties for v4l2src element");
   self->has_sync =
       g_object_class_find_property (G_OBJECT_GET_CLASS (kid), "sync") != NULL;
   if (self->has_sync)
     g_object_set (G_OBJECT (kid), "sync", self->sync, NULL);
   g_object_set (G_OBJECT (kid), "device", self->devnode_path, NULL);
+  g_object_set (G_OBJECT (kid), "num-buffers", self->num_buffers, NULL);
+
   if (klass->configure) {
     klass->configure (self, kid);
   }
 
   self->kid = kid;
+  self->filter = filter;
 
-  gst_bin_add (GST_BIN (self), kid);
+  GST_DEBUG_OBJECT (self, "Creating bin");
+  gst_bin_add_many (GST_BIN (self), kid, filter, NULL);
+  if (!gst_element_link (kid, filter))
+     g_error("failed to link elements to filter\n");
 
+  GST_DEBUG_OBJECT (self, "Configuring elements states");
   /* Ensure the child is brought up to the right state to match the parent. */
   if (GST_STATE (self->kid) < GST_STATE (self))
     gst_element_set_state (self->kid, GST_STATE (self));
+  if (GST_STATE (filter) < GST_STATE (self))
+    gst_element_set_state (filter, GST_STATE (self));
+  GST_DEBUG_OBJECT (self, "Setting filter caps");
+  g_object_set(filter, "caps", self->filter_caps, NULL);
 
+  GST_DEBUG_OBJECT (self, "Setting up ghost pad");
   /* attach ghost pad */
   GST_DEBUG_OBJECT (self, "Re-assigning ghostpad");
   if (!gst_pinesrcbin_attach_ghost_pad (self))
@@ -330,319 +342,26 @@ gst_pinesrcbin_class_init (GstPineSrcBinClass * klass)
   gobject_class->get_property = gst_pinesrcbin_get_property;
 
   eklass->change_state = GST_DEBUG_FUNCPTR (gst_pinesrcbin_change_state);
+
+  g_object_class_install_property (gobject_class, PROP_SYNC,
+      g_param_spec_boolean ("sync", "Sync",
+          "Sync on the clock", DEFAULT_SYNC,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+  g_object_class_install_property (gobject_class, PROP_NUM_BUFFERS,
+      g_param_spec_int ("num-buffers", "Num-buffers",
+          "Number of buffers until EOS, -1 = unlimited", -1, INT_MAX, 1000,
+          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
 }
 
 GST_DEBUG_CATEGORY (pinesrcbin_debug);
 
-struct device_data
-{
-  char path[261];
-  int fd;
-  struct media_v2_topology topology;
-  struct media_device_info info;
-
-  struct media_v2_entity *entities;
-  size_t num_entities;
-  struct media_v2_interface *interfaces;
-  size_t num_interfaces;
-  struct media_v2_pad *pads;
-  size_t num_pads;
-  struct media_v2_link *links;
-  size_t num_links;
-};
-static const struct media_v2_link *
-gst_pinesrcbin_get_link_from_entity (struct device_data *dev, uint32_t id)
-{
-  int i;
-  for (i = 0; i < dev->num_links; i++)
-    if (dev->links[i].sink_id == id)
-      return &dev->links[i];
-  return NULL;
-}
-
-static const struct media_v2_interface *
-gst_pinesrcbin_get_interface_by_id (struct device_data *dev, uint32_t id)
-{
-  int i;
-  for (i = 0; i < dev->num_interfaces; i++)
-    if (dev->interfaces[i].id == id)
-      return &dev->interfaces[i];
-  return NULL;
-}
-
-static const struct media_v2_interface *
-gst_pinesrcbin_get_entity_interface (struct device_data *dev, uint32_t id)
-{
-  const struct media_v2_link *link =
-      gst_pinesrcbin_get_link_from_entity (dev, id);
-  g_print ("entity id: %d\n", id);
-  if (!link)
-    return NULL;
-  g_print ("link id: %d %d\n", link->sink_id, link->source_id);
-  return gst_pinesrcbin_get_interface_by_id (dev, link->source_id);
-}
-
-static const struct media_v2_pad *
-gst_pinesrcbin_get_pad_from_entity (struct device_data *dev, uint32_t id)
-{
-  int i;
-  for (i = 0; i < dev->num_pads; i++) {
-    if (dev->pads[i].entity_id == id)
-      return &dev->pads[i];
-  }
-  return NULL;
-}
-
-static const struct media_v2_entity *
-gst_pinesrcbin_find_media_entity (struct device_data *dev,
-    const char *driver_name)
-{
-  int length = strlen (driver_name);
-  int i;
-  for (i = 0; i < dev->num_entities; i++)
-    g_print ("%s: entity: %s:%s\n", dev->path, dev->entities[i].name,
-        driver_name);
-  for (i = 0; i < dev->num_entities; i++) {
-    if (!strncmp (dev->entities[i].name, driver_name, length))
-      return &dev->entities[i];
-  }
-  return NULL;
-}
-
-static struct device_data *
-gst_pinesrcbin_find_media_device (GstPineSrcBin * self, const char *driver_name)
-{
-  int length = strlen (driver_name);
-  GList *l = self->media_list;
-  while (l) {
-    struct device_data *dev = l->data;
-    const struct media_device_info *info = &dev->info;
-    g_print ("device %s:%s:%s\n", dev->path, info->driver, driver_name);
-    if (!strncmp (info->driver, driver_name, length))
-      return dev;
-    l = l->next;
-  }
-  return NULL;
-}
-
-static gboolean
-get_device_path (struct media_v2_intf_devnode devnode, char *path, int length)
-{
-  char uevent_path[256];
-  snprintf (uevent_path, 256, "/sys/dev/char/%d:%d/uevent", devnode.major,
-      devnode.minor);
-
-  FILE *f = fopen (uevent_path, "r");
-  if (!f) {
-    return FALSE;
-  }
-
-  char line[512];
-  while (fgets (line, 512, f)) {
-    if (strncmp (line, "DEVNAME=", 8) == 0) {
-      // Drop newline
-      int length = strlen (line);
-      if (line[length - 1] == '\n')
-        line[length - 1] = '\0';
-
-      snprintf (path, length, "/dev/%s", line + 8);
-      fclose (f);
-      return TRUE;
-    }
-  }
-
-  fclose (f);
-
-  return FALSE;
-}
-
-static gboolean
-query_autofocus (int fd)
-{
-  struct v4l2_query_ext_ctrl ctrl = { };
-  ctrl.id = V4L2_CID_FOCUS_AUTO;
-  int rc = xioctl (fd, VIDIOC_QUERY_EXT_CTRL, &ctrl);
-  if (rc < 0)
-    return FALSE;
-  return TRUE;
-}
-
-static void
-setup_gain (int fd, int *gain_ctrl, int *gain_max)
-{
-  struct v4l2_query_ext_ctrl ctrl = { };
-  ctrl.id = V4L2_CID_GAIN;
-  int rc = xioctl (fd, VIDIOC_QUERY_EXT_CTRL, &ctrl);
-  if (rc >= 0) {
-    *gain_ctrl = ctrl.id;
-    *gain_max = ctrl.maximum;
-    return;
-  }
-  ctrl.id = V4L2_CID_ANALOGUE_GAIN;
-  rc = xioctl (fd, VIDIOC_QUERY_EXT_CTRL, &ctrl);
-  if (rc >= 0) {
-    *gain_ctrl = ctrl.id;
-    *gain_max = ctrl.maximum;
-    return;
-  }
-}
-
-static gboolean
-camera_control (int fd, uint32_t id, int request, uint32_t * value)
-{
-  struct v4l2_ext_control ctrl = { };
-  ctrl.id = id;
-  ctrl.value = *value;
-
-  struct v4l2_ext_controls ctrls = {
-    .ctrl_class = 0,
-    .which = V4L2_CTRL_WHICH_CUR_VAL,
-    .count = 1,
-    .controls = &ctrl,
-  };
-  if (xioctl (fd, request, &ctrls) == -1) {
-    return TRUE;
-  }
-
-  *value = ctrl.value;
-  return FALSE;
-}
-
-static inline const struct media_v2_pad *
-get_device_pad (const struct device_data *dev, uint32_t id)
-{
-  int i;
-  for (i = 0; i < dev->num_pads; i++) {
-    if (dev->pads[i].id == id) {
-      return &dev->pads[i];
-    }
-  }
-  return NULL;
-}
-
-/* TODO - get media device pad and video device pad and set up link */
-static gboolean
-setup_link (const struct device_data *dev, uint32_t source_pad_id,
-    uint32_t sink_pad_id, gboolean enabled)
-{
-  const struct media_v2_pad *source_pad = get_device_pad (dev, source_pad_id);
-  g_return_val_if_fail (source_pad, FALSE);
-
-  const struct media_v2_pad *sink_pad = get_device_pad (dev, sink_pad_id);
-  g_return_val_if_fail (sink_pad, FALSE);
-
-  struct media_link_desc link = { };
-  link.flags = enabled ? MEDIA_LNK_FL_ENABLED : 0;
-  link.source.entity = source_pad->entity_id;
-  link.source.index = 0;
-  link.sink.entity = sink_pad->entity_id;
-  link.sink.index = 0;
-  if (xioctl (dev->fd, MEDIA_IOC_SETUP_LINK, &link) == -1) {
-    g_printerr ("MEDIA_IOC_SETUP_LINK: %d %s", errno, strerror (errno));
-    return FALSE;
-  }
-
-  return TRUE;
-}
-
 static void
 gst_pinesrcbin_init (GstPineSrcBin * self)
 {
-  self->media_list = NULL;
+  GST_DEBUG_OBJECT (self, "Starting device configuration");
-  struct dirent *dir;
+  gst_pinesrcbin_configure_device(self, "rear");
-  g_print ("starting device scan\n");
-  DIR *d = opendir ("/dev");
-  while ((dir = readdir (d)) != NULL) {
-    if (strncmp (dir->d_name, "media", 5) == 0) {
-      char path[261];
-      int fd;
-      snprintf (path, 261, "/dev/%s", dir->d_name);
-      fd = open (path, O_RDWR);
-      g_print ("opened device: %s: fd=%d\n", path, fd);
-      if (fd >= 0) {
-        int rc = -1;
-        struct device_data *dev = g_new0 (struct device_data, 1);
-        if (!dev)
-          goto out;
-        dev->fd = fd;
-        strncpy (dev->path, path, sizeof (dev->path));
-        g_print ("topology x1\n");
-        rc = xioctl (dev->fd, MEDIA_IOC_G_TOPOLOGY, &dev->topology);
-        if (rc < 0) {
-          g_printerr ("topology x1 error %d %d %s\n", rc,
-              errno, strerror (errno));
-          goto out;
-        }
-        dev->entities =
-            calloc (dev->topology.num_entities,
-            sizeof (struct media_v2_entity));
-        dev->num_entities = dev->topology.num_entities;
-        dev->interfaces =
-            calloc (dev->topology.num_interfaces,
-            sizeof (struct media_v2_interface));
-        dev->num_interfaces = dev->topology.num_interfaces;
-        dev->pads =
-            calloc (dev->topology.num_pads, sizeof (struct media_v2_pad));
-        dev->num_pads = dev->topology.num_pads;
-        dev->links =
-            calloc (dev->topology.num_links, sizeof (struct media_v2_link));
-        dev->num_links = dev->topology.num_links;
-        dev->topology.ptr_entities = (uint64_t) dev->entities;
-        dev->topology.ptr_interfaces = (uint64_t) dev->interfaces;
-        dev->topology.ptr_pads = (uint64_t) dev->pads;
-        dev->topology.ptr_links = (uint64_t) dev->links;
-        g_print ("topology x2\n");
-        rc = xioctl (dev->fd, MEDIA_IOC_G_TOPOLOGY, &dev->topology);
-        if (rc < 0)
-          goto out;
-
-        g_print ("device info\n");
-        rc = xioctl (dev->fd, MEDIA_IOC_DEVICE_INFO, &dev->info);
-        if (rc < 0)
-          goto out;
-        self->media_list = g_list_append (self->media_list, dev);
-        g_print ("added device %s %s\n", dev->path, dev->info.driver);
-      out:
-        if (rc < 0 && dev)
-          g_free (dev);
-      }
-    }
-  }
-  self->media_if = gst_pinesrcbin_find_media_device (self, "sun6i-csi");
-  if (!self->media_if)
-    g_printerr ("can't find device sun6i-csi\n");
-  self->v4l2entity =
-      gst_pinesrcbin_find_media_entity (self->media_if, "sun6i-csi");
-  if (!self->v4l2entity)
-    g_printerr ("can't find entity sun6i-csi\n");
-  /* This is pad for host controller */
-  self->v4l2pad =
-      gst_pinesrcbin_get_pad_from_entity (self->media_if, self->v4l2entity->id);
-  if (!self->v4l2pad)
-    g_printerr ("can't find interface pad sun6i-csi\n");
-  self->v4l2interface =
-      gst_pinesrcbin_get_entity_interface (self->media_if,
-      self->v4l2entity->id);
-  if (!self->v4l2interface)
-    g_printerr ("can't find interface sun6i-csi\n");
-  if (!get_device_path (self->v4l2interface->devnode,
-          self->devnode_path, sizeof (self->devnode_path)))
-    g_printerr ("Failed to get devnode path\n");
-  g_print ("devnode: %s\n", self->devnode_path);
-  /* TODO: source pad? sink pad? */
-//  setup_link(self->media_if, ,self->v4l2interface->pad_id, false);
-  self->fd = open (self->devnode_path, O_RDWR);
-  if (self->fd < 0)
-    g_printerr ("failed to open %s\n", self->devnode_path);
-  self->autofocus = FALSE;
-  if (query_autofocus (self->fd)) {
-    uint32_t enable = 1U;
-    g_print ("autofocus possible\n");
-    self->autofocus = TRUE;
-    camera_control (self->fd, V4L2_CID_FOCUS_AUTO, VIDIOC_S_EXT_CTRLS, &enable);
-  }
-  setup_gain (self->fd, &self->gain_ctrl, &self->gain_max);
   self->sync = DEFAULT_SYNC;
+  self->num_buffers = 1000;
 }
 
 static gboolean

pinesrcbin.h

@@ -0,0 +1,36 @@
+#ifndef PINESRCBIN_H
+#define PINESRCBIN_H
+struct device_data;
+typedef struct _GstPineSrcBin
+{
+  GstBin parent;
+
+  GList *media_list;
+  struct device_data *media_if;
+  /* configuration for subclasses */
+  const gchar *media_klass;     /* Audio/Video/... */
+  GstElementFlags flag;         /* GST_ELEMENT_FLAG_{SINK/SOURCE} */
+
+  /* explicit pointers to stuff used */
+  GstPad *pad;
+  GstCaps *filter_caps;
+  gboolean sync;
+
+  /* < private > */
+  GstElement *kid;
+  GstElement *filter;
+  gboolean has_sync;
+  const gchar *type_klass;      /* Source/Sink */
+  const gchar *media_klass_lc, *type_klass_lc;  /* lower case versions */
+
+  const struct media_v2_entity *v4l2entity;
+  const struct media_v2_pad *v4l2pad;
+  const struct media_v2_interface *v4l2interface;
+  char devnode_path[260];
+  int fd;
+  gboolean autofocus;
+  /* Buffers till EOS */
+  int num_buffers;
+} GstPineSrcBin;
+
+#endif

utility.c

@@ -0,0 +1,621 @@
+#include <stdint.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#include <linux/media.h>
+#include <linux/videodev2.h>
+#include <linux/v4l2-subdev.h>
+
+#include <gst/gst.h>
+#include "pinesrcbin.h"
+#include "utility.h"
+
+static const struct media_v2_link *
+gst_pinesrcbin_get_link_from_entity(struct device_data *dev, uint32_t id);
+static const struct media_v2_interface *
+gst_pinesrcbin_get_interface_by_id(struct device_data *dev, uint32_t id);
+static const struct media_v2_interface *
+gst_pinesrcbin_get_entity_interface(struct device_data *dev, uint32_t id);
+static const struct media_v2_pad *
+gst_pinesrcbin_get_pad_from_entity(struct device_data *dev, uint32_t id);
+static const struct media_v2_entity *
+gst_pinesrcbin_find_media_entity(struct device_data *dev,
+                                 const char *driver_name);
+static struct device_data *
+gst_pinesrcbin_find_media_device(GstPineSrcBin *self, const char *driver_name);
+static gboolean
+get_device_path(struct media_v2_intf_devnode devnode, char *path, int length);
+static gboolean
+query_autofocus(int fd);
+static void
+setup_gain(int fd, int *gain_ctrl, int *gain_max);
+static gboolean
+camera_control(int fd, uint32_t id, int request, uint32_t *value);
+static inline const struct media_v2_pad *
+get_device_pad(const struct device_data *dev, uint32_t id);
+static gboolean
+setup_link(const struct device_data *dev, uint32_t source_pad_id,
+           uint32_t sink_pad_id, gboolean enabled);
+
+static int alloc_device(struct device_data *dev);
+static void disable_all_links(struct device_data *dev);
+static void subdev_set_mode(int subdev_fd, int width,
+		int height,
+		uint32_t bus_code,
+		struct v4l2_fract interval);
+
+struct camera_config;
+int get_camera_config_no(const char *conf_name);
+static struct camera_config *
+get_camera_config(const char *conf_name);
+
+struct camera_data;
+static struct camera_data *
+get_camera_data(const char *conf_name);
+
+static int
+xioctl (int fd, int request, void *arg)
+{
+  int r;
+  do {
+    r = ioctl (fd, request, arg);
+  } while (r == -1 && errno == EINTR);
+  return r;
+}
+
+struct camera_config {
+    char conf_name[128];
+    char camera_name[128];
+    int width;
+    int height;
+    uint32_t bus_code_video;
+    uint32_t bus_code_single;
+    struct v4l2_fract frame_interval;
+};
+
+struct camera_data {
+	struct camera_config *conf;
+	int subdev_fd;
+	const struct media_v2_entity *entity;
+	const struct media_v2_interface *interface;
+	int gain_ctrl;
+	int gain_max;
+	char devnode_path[261];
+};
+struct camera_config configurations[] = {
+	{"front", "gc2145", 320, 240, MEDIA_BUS_FMT_YUYV8_2X8, MEDIA_BUS_FMT_SBGGR8_1X8, {1, 15}},
+	{"rear", "ov5640", 320, 240, MEDIA_BUS_FMT_YUYV8_2X8, MEDIA_BUS_FMT_SBGGR8_1X8, {1, 15}},
+};
+struct camera_data cam_store[] = {
+	{},
+	{}
+};
+
+struct mediabus_to_gst {
+	uint32_t bus_code;
+	const char *gst_format;
+};
+static struct mediabus_to_gst gst_format[] = {
+	{MEDIA_BUS_FMT_SBGGR8_1X8, "BGGR"},
+	{MEDIA_BUS_FMT_SGBRG8_1X8, "GBRG"},
+	{MEDIA_BUS_FMT_SGRBG8_1X8, "GRBG"},
+	{MEDIA_BUS_FMT_SRGGB8_1X8, "RGGB"},
+	{MEDIA_BUS_FMT_SBGGR10_1X10, "BGGR10"},
+	{MEDIA_BUS_FMT_SGBRG10_1X10, "GBRG10"},
+	{MEDIA_BUS_FMT_SGRBG10_1X10, "GRBG10"},
+	{MEDIA_BUS_FMT_SRGGB10_1X10, "RGGB10"},
+	{MEDIA_BUS_FMT_UYVY8_2X8, "UYVY"},
+	{MEDIA_BUS_FMT_YUYV8_2X8, "YUY2"},
+};
+void gst_pinesrcbin_get_gst_caps_data(const char * conf_name,
+		int *width, int * height,
+		const char **format,
+		struct v4l2_fract *interval)
+{
+	int i;
+	const struct camera_config *conf = get_camera_config(conf_name);
+	*width = conf->width;
+	*height = conf->height;
+	*format = NULL;
+	*interval = conf->frame_interval;
+	for (i = 0; i < sizeof(gst_format)/sizeof(gst_format[0]); i++) {
+		if (conf->bus_code_video == gst_format[i].bus_code) {
+			*format = gst_format[i].gst_format;
+			return;
+		}
+	}
+	g_assert(*format);
+}
+
+static const struct media_v2_link *
+gst_pinesrcbin_get_link_from_entity(struct device_data *dev, uint32_t id)
+{
+    int i;
+    for (i = 0; i < dev->num_links; i++)
+        if (dev->links[i].sink_id == id)
+            return &dev->links[i];
+    return NULL;
+}
+
+static const struct media_v2_interface *
+gst_pinesrcbin_get_interface_by_id(struct device_data *dev, uint32_t id)
+{
+    int i;
+    for (i = 0; i < dev->num_interfaces; i++)
+        if (dev->interfaces[i].id == id)
+            return &dev->interfaces[i];
+    return NULL;
+}
+
+static const struct media_v2_interface *
+gst_pinesrcbin_get_entity_interface(struct device_data *dev, uint32_t id)
+{
+    const struct media_v2_link *link =
+        gst_pinesrcbin_get_link_from_entity(dev, id);
+    g_print("entity id: %d\n", id);
+    if (!link)
+        return NULL;
+    g_print("link id: %d %d\n", link->sink_id, link->source_id);
+    return gst_pinesrcbin_get_interface_by_id(dev, link->source_id);
+}
+
+static const struct media_v2_pad *
+gst_pinesrcbin_get_pad_from_entity(struct device_data *dev, uint32_t id)
+{
+    int i;
+    for (i = 0; i < dev->num_pads; i++)
+    {
+        if (dev->pads[i].entity_id == id)
+            return &dev->pads[i];
+    }
+    return NULL;
+}
+
+static const struct media_v2_entity *
+gst_pinesrcbin_find_media_entity(struct device_data *dev,
+                                 const char *driver_name)
+{
+    int length = strlen(driver_name);
+    int i;
+    for (i = 0; i < dev->num_entities; i++)
+        g_print("%s: entity: %s:%d:%s\n", dev->path, dev->entities[i].name,
+                dev->entities[i].id, driver_name);
+    for (i = 0; i < dev->num_entities; i++) {
+        if (!strncmp(dev->entities[i].name, driver_name, length))
+            return &dev->entities[i];
+    }
+    return NULL;
+}
+
+static void disable_all_links(struct device_data *dev)
+{
+    int i, j;
+    for (i = 0; i < dev->num_entities; i++) {
+	    const struct media_v2_pad *sink_pad = 
+	    gst_pinesrcbin_get_pad_from_entity (dev, dev->entities[i].id);
+	    if (!sink_pad)
+		    continue;
+	    if (!(sink_pad->flags & MEDIA_PAD_FL_SINK))
+		    continue;
+	    g_print("sink pad: %d\n", sink_pad->id);
+    	    for (j = 0; j < dev->num_entities; j++) {
+		    if (i == j)
+			    continue;
+	    	const struct media_v2_pad *source_pad = 
+	    	gst_pinesrcbin_get_pad_from_entity (dev, dev->entities[j].id);
+		if (!source_pad)
+			continue;
+	    	g_print("source pad: %d\n", source_pad->id);
+	    	if (!(source_pad->flags & MEDIA_PAD_FL_SOURCE))
+			    continue;
+		g_print("disabling link %d %d\n", source_pad->entity_id, sink_pad->entity_id);
+                setup_link(dev, source_pad->id, sink_pad->id, FALSE);
+	    }
+    }
+#if 0
+      const struct media_v2_link *plink =
+	      gst_pinesrcbin_get_link_from_entity(dev,
+		      dev->entities[i].id);
+      if (plink) {
+              g_print("link %d %08x %08x: %08x\n", plink->id, plink->source_id, plink->sink_id, plink->flags);
+	      if (plink->flags & MEDIA_LNK_FL_ENABLED) {
+		    uint32_t link_type = plink->flags & MEDIA_LNK_FL_LINK_TYPE;
+		    if (link_type == MEDIA_LNK_FL_DATA_LINK) {
+			    g_print("data link %d\n", plink->id);
+			    setup_link(dev, plink->source_id, plink->sink_id, FALSE);
+		    } else if (link_type == MEDIA_LNK_FL_INTERFACE_LINK) {
+			    struct media_v2_interface *iface = st_pinesrcbin_get_interface_by_id(dev, plink->source_id);
+			    g_print("interface link %d entity: %d\n", plink->id, iface->);
+			    continue;
+		    }
+		    const struct media_v2_pad *source_pad, *sink_pad;
+		    g_print("link %d is active\n", plink->id);
+		    source_pad = gst_pinesrcbin_get_pad_from_entity(dev, plink->source_id);
+		    sink_pad = gst_pinesrcbin_get_pad_from_entity(dev, plink->sink_id);
+		    g_assert(source_pad);
+		    g_assert(sink_pad);
+		    setup_link(dev, source_pad->id, sink_pad->id, FALSE);
+#if 0
+		    struct media_link_desc link = {};
+		    link.flags = 0;
+    		    link.source.entity = plink->source_id;
+    		    link.source.index = 0;
+                    link.sink.entity = plink->sink_id;
+    		    link.sink.index = 0;
+    		    if (xioctl(dev->fd, MEDIA_IOC_SETUP_LINK, &link) == -1)
+        		g_printerr("MEDIA_IOC_SETUP_LINK: %d %s", errno, strerror(errno));
+#endif
+#if 0
+		    /* TODO: maintain own links structure */
+		    else
+			plink->flags = 0;
+#endif
+      		}
+      }
+    }
+#endif
+}
+
+static struct device_data *
+gst_pinesrcbin_find_media_device(GstPineSrcBin *self, const char *driver_name)
+{
+    int length = strlen(driver_name);
+    GList *l = self->media_list;
+    while (l)
+    {
+        struct device_data *dev = l->data;
+        const struct media_device_info *info = &dev->info;
+        g_print("device %s:%s:%s\n", dev->path, info->driver, driver_name);
+        if (!strncmp(info->driver, driver_name, length))
+            return dev;
+        l = l->next;
+    }
+    return NULL;
+}
+
+static gboolean
+get_device_path(struct media_v2_intf_devnode devnode, char *path, int length)
+{
+    char uevent_path[256];
+    snprintf(uevent_path, 256, "/sys/dev/char/%d:%d/uevent", devnode.major,
+             devnode.minor);
+
+    FILE *f = fopen(uevent_path, "r");
+    if (!f)
+    {
+        return FALSE;
+    }
+
+    char line[512];
+    while (fgets(line, 512, f))
+    {
+        if (strncmp(line, "DEVNAME=", 8) == 0)
+        {
+            // Drop newline
+            int length = strlen(line);
+            if (line[length - 1] == '\n')
+                line[length - 1] = '\0';
+
+            snprintf(path, length, "/dev/%s", line + 8);
+            fclose(f);
+            return TRUE;
+        }
+    }
+
+    fclose(f);
+
+    return FALSE;
+}
+
+static gboolean
+query_autofocus(int fd)
+{
+    struct v4l2_query_ext_ctrl ctrl = {};
+    ctrl.id = V4L2_CID_FOCUS_AUTO;
+    int rc = xioctl(fd, VIDIOC_QUERY_EXT_CTRL, &ctrl);
+    if (rc < 0)
+        return FALSE;
+    return TRUE;
+}
+
+static void
+setup_gain(int fd, int *gain_ctrl, int *gain_max)
+{
+    struct v4l2_query_ext_ctrl ctrl = {};
+    ctrl.id = V4L2_CID_GAIN;
+    int rc = xioctl(fd, VIDIOC_QUERY_EXT_CTRL, &ctrl);
+    if (rc >= 0)
+    {
+        *gain_ctrl = ctrl.id;
+        *gain_max = ctrl.maximum;
+        return;
+    }
+    ctrl.id = V4L2_CID_ANALOGUE_GAIN;
+    rc = xioctl(fd, VIDIOC_QUERY_EXT_CTRL, &ctrl);
+    if (rc >= 0)
+    {
+        *gain_ctrl = ctrl.id;
+        *gain_max = ctrl.maximum;
+        return;
+    }
+}
+
+static gboolean
+camera_control(int fd, uint32_t id, int request, uint32_t *value)
+{
+    struct v4l2_ext_control ctrl = {};
+    ctrl.id = id;
+    ctrl.value = *value;
+
+    struct v4l2_ext_controls ctrls = {
+        .ctrl_class = 0,
+        .which = V4L2_CTRL_WHICH_CUR_VAL,
+        .count = 1,
+        .controls = &ctrl,
+    };
+    if (xioctl(fd, request, &ctrls) == -1)
+    {
+        return TRUE;
+    }
+
+    *value = ctrl.value;
+    return FALSE;
+}
+
+static inline const struct media_v2_pad *
+get_device_pad(const struct device_data *dev, uint32_t id)
+{
+    int i;
+    for (i = 0; i < dev->num_pads; i++)
+    {
+        if (dev->pads[i].id == id)
+        {
+            return &dev->pads[i];
+        }
+    }
+    return NULL;
+}
+
+/* TODO - get media device pad and video device pad and set up link */
+static gboolean
+setup_link(const struct device_data *dev, uint32_t source_pad_id,
+           uint32_t sink_pad_id, gboolean enabled)
+{
+    const struct media_v2_pad *source_pad = get_device_pad(dev, source_pad_id);
+    g_return_val_if_fail(source_pad, FALSE);
+
+    const struct media_v2_pad *sink_pad = get_device_pad(dev, sink_pad_id);
+    g_return_val_if_fail(sink_pad, FALSE);
+
+    struct media_link_desc link = {};
+    link.flags = enabled ? MEDIA_LNK_FL_ENABLED : 0;
+    link.source.entity = source_pad->entity_id;
+    link.source.index = 0;
+    link.sink.entity = sink_pad->entity_id;
+    link.sink.index = 0;
+    if (xioctl(dev->fd, MEDIA_IOC_SETUP_LINK, &link) == -1)
+    {
+        g_printerr("MEDIA_IOC_SETUP_LINK: %d %s", errno, strerror(errno));
+        return FALSE;
+    }
+
+    return TRUE;
+}
+
+static int alloc_device(struct device_data *dev)
+{
+    int rc = -1;
+    g_print("topology x1\n");
+    rc = xioctl(dev->fd, MEDIA_IOC_G_TOPOLOGY, &dev->topology);
+    if (rc < 0)
+    {
+        g_printerr("topology x1 error %d %d %s\n", rc,
+                   errno, strerror(errno));
+        goto out;
+    }
+    dev->entities =
+        calloc(dev->topology.num_entities,
+               sizeof(struct media_v2_entity));
+    dev->num_entities = dev->topology.num_entities;
+    dev->interfaces =
+        calloc(dev->topology.num_interfaces,
+               sizeof(struct media_v2_interface));
+    dev->num_interfaces = dev->topology.num_interfaces;
+    dev->pads =
+        calloc(dev->topology.num_pads, sizeof(struct media_v2_pad));
+    dev->num_pads = dev->topology.num_pads;
+    dev->links =
+        calloc(dev->topology.num_links, sizeof(struct media_v2_link));
+    dev->num_links = dev->topology.num_links;
+    dev->topology.ptr_entities = (uint64_t)dev->entities;
+    dev->topology.ptr_interfaces = (uint64_t)dev->interfaces;
+    dev->topology.ptr_pads = (uint64_t)dev->pads;
+    dev->topology.ptr_links = (uint64_t)dev->links;
+    g_print("topology x2\n");
+    rc = xioctl(dev->fd, MEDIA_IOC_G_TOPOLOGY, &dev->topology);
+    if (rc < 0)
+        goto out;
+
+    g_print("device info\n");
+    rc = xioctl(dev->fd, MEDIA_IOC_DEVICE_INFO, &dev->info);
+out:
+    return rc;
+}
+
+static void subdev_set_mode(int subdev_fd, int width,
+		int height,
+		uint32_t bus_code,
+		struct v4l2_fract frame_interval)
+{
+  struct v4l2_subdev_frame_interval interval = {};
+  struct v4l2_subdev_format fmt = {};
+  gboolean frame_is_set;
+  interval.pad = 0;
+  interval.interval = frame_interval;
+  if (xioctl(subdev_fd,
+			  VIDIOC_SUBDEV_S_FRAME_INTERVAL,
+			  &interval) == -1)
+	  g_error("VIDIOC_SUBDEV_S_FRAME_INTERVAL %d %s\n",
+			  errno, strerror(errno));
+  frame_is_set =
+	  interval.interval.numerator ==
+	  frame_interval.numerator &&
+	  interval.interval.denominator ==
+	  frame_interval.denominator;
+
+  fmt.pad = 0;
+  fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
+  fmt.format.width = width;
+  fmt.format.height = height;
+  fmt.format.code =
+	  bus_code;
+  fmt.format.field = V4L2_FIELD_ANY;
+  if (xioctl(subdev_fd, VIDIOC_SUBDEV_S_FMT, &fmt) == -1)
+	  g_error ("VIDIOC_SUBDEV_S_FMT: %d %s\n", errno, strerror(errno));
+  if (!frame_is_set) {
+  if (xioctl(subdev_fd,
+			  VIDIOC_SUBDEV_S_FRAME_INTERVAL,
+			  &interval) == -1)
+	  g_error("VIDIOC_SUBDEV_S_FRAME_INTERVAL %d %s\n",
+			  errno, strerror(errno));
+
+  }
+}
+int
+get_camera_config_no(const char *conf_name)
+{
+	int i;
+	for (i = 0;
+		i < sizeof(configurations)/sizeof(configurations[0]); i++) {
+		struct camera_config *d = &configurations[i];
+		if (!strncmp(d->conf_name, conf_name, sizeof(d->conf_name)))
+			return i;
+	}
+	return -1;
+}
+static struct camera_config *
+get_camera_config(const char *conf_name)
+{
+	int conf = get_camera_config_no(conf_name);
+	if (conf < 0)
+		return NULL;
+	else
+		return &configurations[conf];
+}
+static struct camera_data *
+get_camera_data(const char *conf_name)
+{
+	int conf = get_camera_config_no(conf_name);
+	if (conf < 0)
+		return NULL;
+	else {
+		cam_store[conf].conf = &configurations[conf];
+		return &cam_store[conf];
+	}
+}
+void gst_pinesrcbin_configure_device(GstPineSrcBin * self, const char *conf_name)
+{
+  struct camera_config *conf;
+  struct camera_data *cam_data;
+  self->media_list = NULL;
+  struct dirent *dir;
+  conf = get_camera_config(conf_name);
+  if (!conf)
+	  g_error("invalid camera configuration name %s\n", conf_name);
+  cam_data = get_camera_data(conf_name);
+  g_assert(cam_data);
+  GST_DEBUG_OBJECT (self, "Scanning for media devices");
+  DIR *d = opendir ("/dev");
+  while ((dir = readdir (d)) != NULL) {
+    if (strncmp (dir->d_name, "media", 5) == 0) {
+      char path[261];
+      int fd;
+      snprintf (path, 261, "/dev/%s", dir->d_name);
+      fd = open (path, O_RDWR);
+      GST_DEBUG_OBJECT (self, "Opened device:  %s: fd=%d\n",  path, fd);
+      if (fd >= 0) {
+        int rc = -1;
+        struct device_data *dev = g_new0 (struct device_data, 1);
+        if (!dev)
+          goto out;
+        dev->fd = fd;
+        strncpy (dev->path, path, sizeof (dev->path));
+        rc = alloc_device(dev);
+        if (rc < 0)
+          goto out;
+        self->media_list = g_list_append(self->media_list, dev);
+        GST_DEBUG_OBJECT (self, "added device %s %s\n", dev->path, dev->info.driver);
+      out:
+        if (rc < 0 && dev)
+          g_free (dev);
+      }
+    }
+  }
+  /* TODO: configure file */
+  self->media_if = gst_pinesrcbin_find_media_device (self, "sun6i-csi");
+  if (!self->media_if)
+    g_error ("can't find device sun6i-csi\n");
+  /* sink entity */
+  self->v4l2entity =
+      gst_pinesrcbin_find_media_entity (self->media_if, "sun6i-csi");
+  if (!self->v4l2entity)
+    g_error ("can't find entity sun6i-csi\n");
+  GST_DEBUG_OBJECT (self, "sink entity: %d %s\n", self->v4l2entity->id, self->v4l2entity->name);
+  /* This is sink pad (for host controller) */
+  self->v4l2pad =
+      gst_pinesrcbin_get_pad_from_entity (self->media_if, self->v4l2entity->id);
+  GST_DEBUG_OBJECT (self, "sink pad: %d\n", self->v4l2pad->id);
+  if (!self->v4l2pad)
+    g_error ("can't find interface pad sun6i-csi\n");
+  self->v4l2interface =
+      gst_pinesrcbin_get_entity_interface (self->media_if,
+      self->v4l2entity->id);
+  if (!self->v4l2interface)
+    g_printerr ("can't find interface sun6i-csi\n");
+  GST_DEBUG_OBJECT (self, "sink interface: %d\n", self->v4l2interface->id);
+  if (!get_device_path (self->v4l2interface->devnode,
+          self->devnode_path, sizeof (self->devnode_path)))
+    g_error ("Failed to get devnode path\n");
+  GST_DEBUG_OBJECT (self, "sink interface devnode path: %s\n", self->devnode_path);
+  g_print ("devnode: %s\n", self->devnode_path);
+  /* /dev/video device fd */
+  self->fd = open (self->devnode_path, O_RDWR);
+  if (self->fd < 0)
+    g_error ("failed to open %s\n", self->devnode_path);
+  /* TODO: source pad? sink pad? Need to disable active link*/
+//  setup_link(self->media_if, ,self->v4l2interface->pad_id, false);
+  disable_all_links(self->media_if);
+  cam_data->entity = gst_pinesrcbin_find_media_entity(self->media_if, conf->camera_name);
+  GST_DEBUG_OBJECT (self, "camera: %s: source interface entity %d\n", conf->camera_name, cam_data->entity->id);
+  
+  cam_data->interface =
+      gst_pinesrcbin_get_entity_interface (self->media_if,
+      cam_data->entity->id);
+  GST_DEBUG_OBJECT (self, "camera: %s: source interface %d\n", conf->camera_name, cam_data->interface->id);
+  if (!get_device_path (cam_data->interface->devnode,
+          cam_data->devnode_path, sizeof (cam_data->devnode_path)))
+    g_error ("Failed to get subdevice devnode path for %s\n", conf->camera_name);
+  GST_DEBUG_OBJECT (self, "source subdevice %s\n", cam_data->devnode_path);
+  cam_data->subdev_fd = open (cam_data->devnode_path, O_RDWR);
+  if (cam_data->subdev_fd < 0)
+	  g_error ("Failed to open subdevice: %s\n", cam_data->devnode_path);
+  
+  self->autofocus = FALSE;
+  if (query_autofocus (cam_data->subdev_fd)) {
+    uint32_t enable = 1U;
+    g_print ("autofocus possible\n");
+    self->autofocus = TRUE;
+    camera_control (cam_data->subdev_fd, V4L2_CID_FOCUS_AUTO, VIDIOC_S_EXT_CTRLS, &enable);
+  }
+  setup_gain (cam_data->subdev_fd, &cam_data->gain_ctrl, &cam_data->gain_max);
+  /* now configuring camera modes */
+  GST_DEBUG_OBJECT (self, "configuring camera modes\n");
+  subdev_set_mode(cam_data->subdev_fd, conf->width,
+		  conf->height, conf->bus_code_video,
+		  conf->frame_interval);
+}
+

utility.h

@@ -0,0 +1,26 @@
+#ifndef UTILITY_H
+#define UTILITY_H
+struct _GstPineSrcBin;
+typedef struct _GstPineSrcBin GstPineSrcBin;
+struct device_data
+{
+  char path[261];
+  int fd;
+  struct media_v2_topology topology;
+  struct media_device_info info;
+
+  struct media_v2_entity *entities;
+  size_t num_entities;
+  struct media_v2_interface *interfaces;
+  size_t num_interfaces;
+  struct media_v2_pad *pads;
+  size_t num_pads;
+  struct media_v2_link *links;
+  size_t num_links;
+};
+void gst_pinesrcbin_configure_device(GstPineSrcBin * self, const char *conf_name);
+void gst_pinesrcbin_get_gst_caps_data(const char * conf_name,
+		int *width, int * height, const char **format,
+		struct v4l2_fract *interval);
+
+#endif