EmberJS: Use AJAX data from parent resource in child route - ember.js

Question

Let's say that I want to create an ember app that displays a matrix and allows
you to click on a cell for more information. My routes look like this:
App.Router.map(function() {
this.resource("data", function() {
this.route("cell", {path: ':row/:col'});
});
});
App.DataRoute = Ember.Route.extend({
model: function(params) {
return App.DataModel.create({
/* information needed for AJAX query */
});
},
});
App.DataCellRoute = Ember.Route.extend({
model: function(params) {
return Ember.Object.create({
row: params.row,
col: params.col
});
},
serialize: function(model) {
return {row: model.row, col: model.col};
},
});
Furthermore, the matrix load is expensive (say, a slow AJAX request), so I
don't want to have to reload the data when I transition to the child route.
Also, assume that the data in the cells can't be serialized, so I can't just
pass the cell data in the URL.
Here's what the controllers looks like:
App.DataController = Ember.ArrayController.extend({
model: null,
content: Ember.A(),
loadData: function() {
self = this;
$.ajax({
/* ... */,
success: function(data) {
App.beginPropertyChanges();
self.clear();
data.forEach(function(row) {
self.pushObject(row);
});
App.endPropertyChanges();
},
}.observes('model'),
});
App.DataCellController = Ember.ObjectController.extend({
needs: 'data',
model: {row: 0, col: 0},
matrixBinding: 'controllers.data.content',
cell: function() {
var xy = this.get('model');
return this.get('matrix')[xy.row][xy.col];
}.property('matrix.#each', 'model'),
});
When you click on a cell, its view tells DataController to send an event that
transitons to data.cell with the appropriate row/column. I expected that
when I transition to the data.cell route, I should have access to
DataController's content. However, all I get is the default empty array.
What am I doing wrong?
EDIT:
To answer the question 'how is DataController.content set', I updated the
question to show a more accurate depicition of DataRoute and
DataController. Basically, DataController has a model that contains
information pertinent to the AJAX request. I have a function, loadData,
which observes the model and loads content.