dm: cros_ec: Convert the I2C tunnel code to use driver model

The Chrome OS EC supports tunnelling through to an I2C bus on the EC. This
currently uses a copy of the I2C command code and a special 'crosec'
sub-command.

With driver model we can define an I2C bus which tunnels through to the EC,
and use the normal 'i2c' command to access it. This simplifies the code and
removes some duplication.

Add an I2C driver which tunnels through to the EC. Adjust the EC code to
support binding child devices so that it can be set up. Adjust the existing
I2C xfer function to fit driver model better.

For now the old code remains to allow things to still work. It will be
removed in a later patch once the new flow is fully enabled.

Signed-off-by: Simon Glass <sjg@chromium.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/drivers/i2c/cros_ec_tunnel.c b/drivers/i2c/cros_ec_tunnel.c
new file mode 100644
index 0000000000..7ab1fd898a
--- /dev/null
+++ b/drivers/i2c/cros_ec_tunnel.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <cros_ec.h>
+#include <errno.h>
+#include <i2c.h>
+
+static int cros_ec_i2c_set_bus_speed(struct udevice *dev, unsigned int speed)
+{
+	return 0;
+}
+
+static int cros_ec_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
+			    int nmsgs)
+{
+	return cros_ec_i2c_tunnel(dev->parent, msg, nmsgs);
+}
+
+static const struct dm_i2c_ops cros_ec_i2c_ops = {
+	.xfer		= cros_ec_i2c_xfer,
+	.set_bus_speed	= cros_ec_i2c_set_bus_speed,
+};
+
+static const struct udevice_id cros_ec_i2c_ids[] = {
+	{ .compatible = "google,cros-ec-i2c-tunnel" },
+	{ }
+};
+
+U_BOOT_DRIVER(cros_ec_tunnel) = {
+	.name	= "cros_ec_tunnel",
+	.id	= UCLASS_I2C,
+	.of_match = cros_ec_i2c_ids,
+	.per_child_auto_alloc_size = sizeof(struct dm_i2c_chip),
+	.ops	= &cros_ec_i2c_ops,
+};