--- /dev/null
+greybus-y := core.o
+
+obj-m += greybus.o
+obj-m += i2c-gb.o
+
+KERNELVER ?= $(shell uname -r)
+KERNELDIR ?= /lib/modules/$(KERNELVER)/build
+PWD := $(shell pwd)
+
+all: module
+
+module:
+ $(MAKE) -C $(KERNELDIR) M=$(PWD)
+
+clean:
+ rm -f *.o *~ core .depend .*.cmd *.ko *.mod.c
+ rm -f Module.markers Module.symvers modules.order
+ rm -rf .tmp_versions Modules.symvers
+
+coccicheck:
+ $(MAKE) -C $(KERNELDIR) M=$(PWD) coccicheck
+
--- /dev/null
+/*
+ * Greybus "Core"
+ *
+ * Copyright 2014 Google Inc.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+
+#include "greybus.h"
+
+/* Allow greybus to be disabled at boot if needed */
+static bool nogreybus;
+#ifdef MODULE
+module_param(nogreybus, bool, 0444);
+#else
+core_param(nogreybus, bool, 0444);
+#endif
+int greybus_disabled(void)
+{
+ return nogreybus;
+}
+EXPORT_SYMBOL_GPL(greybus_disabled);
+
+static int greybus_match_one_id(struct greybus_device *gdev,
+ const struct greybus_device_id *id)
+{
+ struct greybus_descriptor *des = &gdev->descriptor;
+
+ if ((id->match_flags & GREYBUS_DEVICE_ID_MATCH_VENDOR) &&
+ (des->wVendor != id->wVendor))
+ return 0;
+
+ if ((id->match_flags & GREYBUS_DEVICE_ID_MATCH_PRODUCT) &&
+ (des->wProduct != id->wProduct))
+ return 0;
+
+ if ((id->match_flags & GREYBUS_DEVICE_ID_MATCH_SERIAL) &&
+ (des->lSerialNumber != id->lSerialNumber))
+ return 0;
+
+ return 1;
+}
+
+static const struct greybus_device_id *greybus_match_id(
+ struct greybus_device *gdev,
+ const struct greybus_device_id *id)
+{
+ if (id == NULL)
+ return NULL;
+
+ for (; id->wVendor || id->wProduct || id->lSerialNumber ||
+ id->driver_info ; id++) {
+ if (greybus_match_one_id(gdev, id))
+ return id;
+ }
+
+ return NULL;
+}
+
+static int greybus_device_match(struct device *dev, struct device_driver *drv)
+{
+ struct greybus_driver *driver = to_greybus_driver(dev->driver);
+ struct greybus_device *gdev = to_greybus_device(dev);
+ const struct greybus_device_id *id;
+
+ id = greybus_match_id(gdev, driver->id_table);
+ if (id)
+ return 1;
+ /* FIXME - Dyanmic ids? */
+ return 0;
+}
+
+static int greybus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ /* struct greybus_device *gdev = to_greybus_device(dev); */
+
+ /* FIXME - add some uevents here... */
+ return 0;
+}
+
+struct bus_type greybus_bus_type = {
+ .name = "greybus",
+ .match = greybus_device_match,
+ .uevent = greybus_uevent,
+};
+
+static int greybus_probe(struct device *dev)
+{
+ struct greybus_driver *driver = to_greybus_driver(dev->driver);
+ struct greybus_device *gdev = to_greybus_device(dev);
+ const struct greybus_device_id *id;
+ int retval;
+
+ /* match id */
+ id = greybus_match_id(gdev, driver->id_table);
+ if (!id)
+ return -ENODEV;
+
+ retval = driver->probe(gdev, id);
+ if (retval)
+ return retval;
+
+ return 0;
+}
+
+static int greybus_remove(struct device *dev)
+{
+ struct greybus_driver *driver = to_greybus_driver(dev->driver);
+ struct greybus_device *gdev = to_greybus_device(dev);
+
+ driver->disconnect(gdev);
+ return 0;
+}
+
+int greybus_register_driver(struct greybus_driver *driver, struct module *owner,
+ const char *mod_name)
+{
+ int retval;
+
+ if (greybus_disabled())
+ return -ENODEV;
+
+ driver->driver.name = driver->name;
+ driver->driver.probe = greybus_probe;
+ driver->driver.remove = greybus_remove;
+ driver->driver.owner = owner;
+ driver->driver.mod_name = mod_name;
+
+ retval = driver_register(&driver->driver);
+ if (retval)
+ return retval;
+
+ pr_info("registered new driver %s\n", driver->name);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(greybus_register_driver);
+
+void greybus_deregister(struct greybus_driver *driver)
+{
+ driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL_GPL(greybus_deregister);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");
--- /dev/null
+/*
+ * Greybus driver and device API
+ *
+ * Copyright 2014 Google Inc.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#ifndef __LINUX_GREYBUS_H
+#define __LINUX_GREYBUS_H
+
+#ifdef __KERNEL__
+
+#include <linux/list.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include "greybus_id.h"
+
+
+#define GREYBUS_DEVICE_ID_MATCH_DEVICE \
+ (GREYBUS_DEVICE_ID_MATCH_VENDOR | GREYBUS_DEVICE_ID_MATCH_PRODUCT)
+
+#define GREYBUS_DEVICE(vendor, product) \
+ .match_flags = GREYBUS_DEVICE_ID_MATCH_DEVICE, \
+ .wVendor = (vendor), \
+ .wProduct = (product),
+
+#define GREYBUS_DEVICE_SERIAL(serial) \
+ .match_flags = GREYBUS_DEVICE_ID_MATCH_SERIAL, \
+ .lSerial = (serial),
+
+
+struct greybus_descriptor {
+ __u16 wVendor;
+ __u16 wProduct;
+ __u64 lSerialNumber;
+};
+
+struct greybus_device {
+ struct device dev;
+ struct greybus_descriptor descriptor;
+};
+#define to_greybus_device(d) container_of(d, struct greybus_device, dev)
+
+struct greybus_driver {
+ const char *name;
+
+ int (*probe) (struct greybus_device *gdev,
+ const struct greybus_device_id *id);
+ void (*disconnect) (struct greybus_device *gdev);
+
+ int (*suspend) (struct greybus_device *gdev, pm_message_t message);
+ int (*resume) (struct greybus_device *gdev);
+
+ const struct greybus_device_id *id_table;
+
+ struct device_driver driver;
+};
+#define to_greybus_driver(d) container_of(d, struct greybus_driver, driver)
+
+static inline void greybus_set_drvdata(struct greybus_device *gdev, void *data)
+{
+ dev_set_drvdata(&gdev->dev, data);
+}
+
+static inline void *greybus_get_drvdata(struct greybus_device *gdev)
+{
+ return dev_get_drvdata(&gdev->dev);
+}
+
+/* Don't call these directly, use the module_greybus_driver() macro instead */
+int greybus_register_driver(struct greybus_driver *driver,
+ struct module *module, const char *mod_name);
+void greybus_deregister(struct greybus_driver *driver);
+
+/* define to get proper THIS_MODULE and KBUILD_MODNAME values */
+#define greybus_register(driver) \
+ greybus_register_driver(driver, THIS_MODULE, KBUILD_MODNAME)
+
+/**
+ * module_greybus_driver() - Helper macro for registering a Greybus driver
+ * @__greybus_driver: greybus_driver structure
+ *
+ * Helper macro for Greybus drivers to set up proper module init / exit
+ * functions. Replaces module_init() and module_exit() and keeps people from
+ * printing pointless things to the kernel log when their driver is loaded.
+ */
+#define module_greybus_driver(__greybus_driver) \
+ module_driver(__greybus_driver, greybus_register, greybus_deregister)
+
+extern struct bus_type greybus_bus_type;
+
+int greybus_disabled(void);
+
+
+#endif /* __KERNEL__ */
+#endif /* __LINUX_GREYBUS_H */
--- /dev/null
+/* FIXME
+ * move this to include/linux/mod_devicetable.h when merging
+ */
+
+#ifndef __LINUX_GREYBUS_ID_H
+#define __LINUX_GREYBUS_ID_H
+
+#include <linux/types.h>
+#include <linux/mod_devicetable.h>
+
+
+struct greybus_device_id {
+ __u16 match_flags;
+ __u16 wVendor;
+ __u16 wProduct;
+ __u64 lSerialNumber;
+
+ kernel_ulong_t driver_info
+ __attribute__((aligned(sizeof(kernel_ulong_t))));
+};
+
+/* Used to match the greybus_device_id */
+#define GREYBUS_DEVICE_ID_MATCH_VENDOR BIT(0)
+#define GREYBUS_DEVICE_ID_MATCH_PRODUCT BIT(1)
+#define GREYBUS_DEVICE_ID_MATCH_SERIAL BIT(2)
+
+#endif /* __LINUX_GREYBUS_H */
--- /dev/null
+/*
+ * I2C bridge driver for the Greybus "generic" I2C module.
+ *
+ * Copyright 2014 Google Inc.
+ *
+ * Released under the GPLv2 only.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include "greybus.h"
+
+struct i2c_gb_data {
+ struct i2c_adapter *adapter;
+ struct greybus_device *gdev;
+};
+
+static const struct greybus_device_id id_table[] = {
+ { GREYBUS_DEVICE(0x42, 0x42) }, /* make shit up */
+ { }, /* terminating NULL entry */
+};
+
+/* We BETTER be able to do SMBUS protocl calls, otherwise we are bit-banging the
+ * slowest thing possible over the fastest bus possible, crazy...
+ * FIXME - research this, for now just assume we can
+ */
+
+
+static s32 i2c_gb_access(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write, u8 command,
+ int size, union i2c_smbus_data *data)
+{
+ struct i2c_gb_data *i2c_gb_data;
+ struct greybus_device *gdev;
+
+ i2c_gb_data = i2c_get_adapdata(adap);
+ gdev = i2c_gb_data->gdev;
+
+ // FIXME - do the actual work of sending a i2c message here...
+ switch (size) {
+ case I2C_SMBUS_QUICK:
+ case I2C_SMBUS_BYTE:
+ case I2C_SMBUS_BYTE_DATA:
+ case I2C_SMBUS_WORD_DATA:
+ case I2C_SMBUS_PROC_CALL:
+ case I2C_SMBUS_BLOCK_DATA:
+ case I2C_SMBUS_I2C_BLOCK_BROKEN:
+ case I2C_SMBUS_BLOCK_PROC_CALL:
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ default:
+ dev_err(&gdev->dev, "Unsupported transaction %d\n", size);
+ return -EOPNOTSUPP;
+ }
+
+ return 0;
+}
+
+static u32 i2c_gb_func(struct i2c_adapter *adapter)
+{
+ // FIXME - someone figure out what we really can support, for now just guess...
+ return I2C_FUNC_SMBUS_QUICK |
+ I2C_FUNC_SMBUS_BYTE |
+ I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_BLOCK_DATA |
+ I2C_FUNC_SMBUS_WRITE_I2C_BLOCK |
+ I2C_FUNC_SMBUS_PEC |
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK;
+}
+
+static const struct i2c_algorithm smbus_algorithm = {
+ .smbus_xfer = i2c_gb_access,
+ .functionality = i2c_gb_func,
+};
+
+static int i2c_gb_probe(struct greybus_device *gdev, const struct greybus_device_id *id)
+{
+ struct i2c_gb_data *i2c_gb_data;
+ struct i2c_adapter *adapter;
+
+ i2c_gb_data = kzalloc(sizeof(*i2c_gb_data), GFP_KERNEL);
+ if (!i2c_gb_data)
+ return -ENOMEM;
+ adapter = kzalloc(sizeof(*adapter), GFP_KERNEL);
+ if (!adapter) {
+ kfree(i2c_gb_data);
+ return -ENOMEM;
+ }
+
+ i2c_set_adapdata(adapter, i2c_gb_data);
+ adapter->owner = THIS_MODULE;
+ adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adapter->algo = &smbus_algorithm;
+
+ i2c_gb_data->gdev = gdev;
+ i2c_gb_data->adapter = adapter;
+
+ greybus_set_drvdata(gdev, i2c_gb_data);
+ return 0;
+}
+
+static void i2c_gb_disconnect(struct greybus_device *gdev)
+{
+ struct i2c_gb_data *i2c_gb_data;
+
+ i2c_gb_data = greybus_get_drvdata(gdev);
+ i2c_del_adapter(i2c_gb_data->adapter);
+ kfree(i2c_gb_data->adapter);
+ kfree(i2c_gb_data);
+}
+
+static struct greybus_driver i2c_gb_driver = {
+ .probe = i2c_gb_probe,
+ .disconnect = i2c_gb_disconnect,
+ .id_table = id_table,
+};
+
+module_greybus_driver(i2c_gb_driver);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");