Import an Open Firmware I2C bus module. This attaches firmware device tree

indicated I2C devices, and provides an ofw_bus interface for driver probing.
This should be MI, but is currently provided only on PowerPC due to lack of
sparc64 hardware with an I2C controller.

Discussed on:	freebsd-arch

1 files changed, 183 insertions, 0 deletions

diff --git a/sys/dev/ofw/ofw_iicbus.c b/sys/dev/ofw/ofw_iicbus.c
new file mode 100644
index 0000000..1b0a274
--- /dev/null
+++ b/sys/dev/ofw/ofw_iicbus.c
@@ -0,0 +1,183 @@
+/*-
+ * Copyright (c) 2009, Nathan Whitehorn <nwhitehorn@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice unmodified, this list of conditions, and the following
+ *    disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/bus.h>
+#include <sys/kernel.h>
+#include <sys/libkern.h>
+#include <sys/lock.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+
+#include <dev/iicbus/iicbus.h>
+#include <dev/iicbus/iiconf.h>
+#include <dev/ofw/ofw_bus.h>
+#include <dev/ofw/ofw_bus_subr.h>
+#include <dev/ofw/openfirm.h>
+
+#include "iicbus_if.h"
+
+/* Methods */
+static device_probe_t ofw_iicbus_probe;
+static device_attach_t ofw_iicbus_attach;
+static device_t ofw_iicbus_add_child(device_t dev, int order, const char *name,
+    int unit);
+static const struct ofw_bus_devinfo *ofw_iicbus_get_devinfo(device_t bus,
+    device_t dev);
+
+static device_method_t ofw_iicbus_methods[] = {
+	/* Device interface */
+	DEVMETHOD(device_probe,		ofw_iicbus_probe),
+	DEVMETHOD(device_attach,	ofw_iicbus_attach),
+
+	/* Bus interface */
+	DEVMETHOD(bus_child_pnpinfo_str, ofw_bus_gen_child_pnpinfo_str),
+	DEVMETHOD(bus_add_child,	ofw_iicbus_add_child),
+
+	/* ofw_bus interface */
+	DEVMETHOD(ofw_bus_get_devinfo,	ofw_iicbus_get_devinfo),
+	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
+	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
+	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
+	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
+	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
+
+	{ 0, 0 }
+};
+
+struct ofw_iicbus_devinfo {
+	struct iicbus_ivar	opd_dinfo;
+	struct ofw_bus_devinfo	opd_obdinfo;
+};
+
+static devclass_t ofwiicbus_devclass;
+
+DEFINE_CLASS_1(iicbus, ofw_iicbus_driver, ofw_iicbus_methods, 1 /* no softc */,
+    iicbus_driver);
+DRIVER_MODULE(ofw_iicbus, iichb, ofw_iicbus_driver, ofwiicbus_devclass, 0, 0);
+MODULE_VERSION(ofw_iicbus, 1);
+MODULE_DEPEND(ofw_iicbus, iicbus, 1, 1, 1);
+
+static int
+ofw_iicbus_probe(device_t dev)
+{
+
+	if (ofw_bus_get_node(dev) == 0)
+		return (ENXIO);
+	device_set_desc(dev, "OFW I2C bus");
+
+	return (0);
+}
+
+static int
+ofw_iicbus_attach(device_t dev)
+{
+	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
+	struct ofw_iicbus_devinfo *dinfo;
+	phandle_t node, child;
+	device_t childdev;
+	uint32_t addr;
+
+	sc->dev = dev;
+	mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF);
+	iicbus_reset(dev, IIC_FASTEST, 0, NULL);
+
+	bus_generic_probe(dev);
+	bus_enumerate_hinted_children(dev);
+
+	/*
+	 * Attach those children represented in the device tree.
+	 */
+
+	node = ofw_bus_get_node(dev);
+
+	for (child = OF_child(node); child != 0; child = OF_peer(child)) {
+		if (OF_getprop(child, "reg", &addr, sizeof(addr)) == -1)
+			continue;
+
+		/*
+		 * Now set up the I2C and OFW bus layer devinfo and add it
+		 * to the bus.
+		 */
+
+		dinfo = malloc(sizeof(struct ofw_iicbus_devinfo), M_DEVBUF,
+		    M_NOWAIT | M_ZERO);
+		if (dinfo == NULL)
+			continue;
+		dinfo->opd_dinfo.addr = addr;
+		if (ofw_bus_gen_setup_devinfo(&dinfo->opd_obdinfo, child) !=
+		    0) {
+			free(dinfo, M_DEVBUF);
+			continue;
+		}
+		childdev = device_add_child(dev, NULL, -1);
+		device_set_ivars(childdev, dinfo);
+	}
+
+	return (bus_generic_attach(dev));
+}
+
+static device_t
+ofw_iicbus_add_child(device_t dev, int order, const char *name, int unit)
+{
+	device_t child;
+	struct ofw_iicbus_devinfo *devi;
+
+	child = device_add_child_ordered(dev, order, name, unit);
+	if (child == NULL)
+		return (child);
+	devi = malloc(sizeof(struct ofw_iicbus_devinfo), M_DEVBUF, 
+	    M_NOWAIT | M_ZERO);
+	if (devi == NULL) {
+		device_delete_child(dev, child);
+		return (0);
+	}
+
+	/* NULL all the OFW-related parts of the ivars for non-OFW children */
+	
+	devi->opd_obdinfo.obd_node = -1;
+	devi->opd_obdinfo.obd_name = NULL;
+	devi->opd_obdinfo.obd_compat = NULL;
+	devi->opd_obdinfo.obd_type = NULL;
+	devi->opd_obdinfo.obd_model = NULL;
+
+	device_set_ivars(child, devi);
+	
+	return (child);
+}
+
+static const struct ofw_bus_devinfo *
+ofw_iicbus_get_devinfo(device_t bus, device_t dev)
+{
+	struct ofw_iicbus_devinfo *dinfo;
+
+	dinfo = device_get_ivars(dev);
+	return (&dinfo->opd_obdinfo);
+}
+