1 files changed, 360 insertions, 0 deletions
diff --git a/drivers/staging/greybus/gbphy.c b/drivers/staging/greybus/gbphy.c
new file mode 100644
index 000000000000..bcde7c9a0f17
--- /dev/null
+++ b/drivers/staging/greybus/gbphy.c
@@ -0,0 +1,360 @@
+/*
+ * Greybus Bridged-Phy Bus driver
+ *
+ * Copyright 2014 Google Inc.
+ * Copyright 2014 Linaro Ltd.
+ *
+ * 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/slab.h>
+#include <linux/device.h>
+
+#include "greybus.h"
+#include "gbphy.h"
+
+#define GB_GBPHY_AUTOSUSPEND_MS	3000
+
+struct gbphy_host {
+	struct gb_bundle *bundle;
+	struct list_head devices;
+};
+
+static DEFINE_IDA(gbphy_id);
+
+static ssize_t protocol_id_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct gbphy_device *gbphy_dev = to_gbphy_dev(dev);
+
+	return sprintf(buf, "0x%02x\n", gbphy_dev->cport_desc->protocol_id);
+}
+static DEVICE_ATTR_RO(protocol_id);
+
+static struct attribute *gbphy_dev_attrs[] = {
+	&dev_attr_protocol_id.attr,
+	NULL,
+};
+
+ATTRIBUTE_GROUPS(gbphy_dev);
+
+static void gbphy_dev_release(struct device *dev)
+{
+	struct gbphy_device *gbphy_dev = to_gbphy_dev(dev);
+
+	ida_simple_remove(&gbphy_id, gbphy_dev->id);
+	kfree(gbphy_dev);
+}
+
+#ifdef CONFIG_PM
+static int gb_gbphy_idle(struct device *dev)
+{
+	pm_runtime_mark_last_busy(dev);
+	pm_request_autosuspend(dev);
+	return 0;
+}
+#endif
+
+static const struct dev_pm_ops gb_gbphy_pm_ops = {
+	SET_RUNTIME_PM_OPS(pm_generic_runtime_suspend,
+			   pm_generic_runtime_resume,
+			   gb_gbphy_idle)
+};
+
+static struct device_type greybus_gbphy_dev_type = {
+	.name	 =	"gbphy_device",
+	.release =	gbphy_dev_release,
+	.pm	=	&gb_gbphy_pm_ops,
+};
+
+static int gbphy_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+	struct gbphy_device *gbphy_dev = to_gbphy_dev(dev);
+	struct greybus_descriptor_cport *cport_desc = gbphy_dev->cport_desc;
+	struct gb_bundle *bundle = gbphy_dev->bundle;
+	struct gb_interface *intf = bundle->intf;
+	struct gb_module *module = intf->module;
+	struct gb_host_device *hd = intf->hd;
+
+	if (add_uevent_var(env, "BUS=%u", hd->bus_id))
+		return -ENOMEM;
+	if (add_uevent_var(env, "MODULE=%u", module->module_id))
+		return -ENOMEM;
+	if (add_uevent_var(env, "INTERFACE=%u", intf->interface_id))
+		return -ENOMEM;
+	if (add_uevent_var(env, "GREYBUS_ID=%08x/%08x",
+			   intf->vendor_id, intf->product_id))
+		return -ENOMEM;
+	if (add_uevent_var(env, "BUNDLE=%u", gbphy_dev->bundle->id))
+		return -ENOMEM;
+	if (add_uevent_var(env, "BUNDLE_CLASS=%02x", bundle->class))
+		return -ENOMEM;
+	if (add_uevent_var(env, "GBPHY=%u", gbphy_dev->id))
+		return -ENOMEM;
+	if (add_uevent_var(env, "PROTOCOL_ID=%02x", cport_desc->protocol_id))
+		return -ENOMEM;
+
+	return 0;
+}
+
+static const struct gbphy_device_id *
+gbphy_dev_match_id(struct gbphy_device *gbphy_dev, struct gbphy_driver *gbphy_drv)
+{
+	const struct gbphy_device_id *id = gbphy_drv->id_table;
+
+	if (!id)
+		return NULL;
+
+	for (; id->protocol_id; id++)
+		if (id->protocol_id == gbphy_dev->cport_desc->protocol_id)
+			return id;
+
+	return NULL;
+}
+
+static int gbphy_dev_match(struct device *dev, struct device_driver *drv)
+{
+	struct gbphy_driver *gbphy_drv = to_gbphy_driver(drv);
+	struct gbphy_device *gbphy_dev = to_gbphy_dev(dev);
+	const struct gbphy_device_id *id;
+
+	id = gbphy_dev_match_id(gbphy_dev, gbphy_drv);
+	if (id)
+		return 1;
+
+	return 0;
+}
+
+static int gbphy_dev_probe(struct device *dev)
+{
+	struct gbphy_driver *gbphy_drv = to_gbphy_driver(dev->driver);
+	struct gbphy_device *gbphy_dev = to_gbphy_dev(dev);
+	const struct gbphy_device_id *id;
+	int ret;
+
+	id = gbphy_dev_match_id(gbphy_dev, gbphy_drv);
+	if (!id)
+		return -ENODEV;
+
+	/* for old kernels we need get_sync to resume parent devices */
+	ret = gb_pm_runtime_get_sync(gbphy_dev->bundle);
+	if (ret < 0)
+		return ret;
+
+	pm_runtime_set_autosuspend_delay(dev, GB_GBPHY_AUTOSUSPEND_MS);
+	pm_runtime_use_autosuspend(dev);
+	pm_runtime_get_noresume(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	/*
+	 * Drivers should call put on the gbphy dev before returning
+	 * from probe if they support runtime pm.
+	 */
+	ret = gbphy_drv->probe(gbphy_dev, id);
+	if (ret) {
+		pm_runtime_disable(dev);
+		pm_runtime_set_suspended(dev);
+		pm_runtime_put_noidle(dev);
+		pm_runtime_dont_use_autosuspend(dev);
+	}
+
+	gb_pm_runtime_put_autosuspend(gbphy_dev->bundle);
+
+	return ret;
+}
+
+static int gbphy_dev_remove(struct device *dev)
+{
+	struct gbphy_driver *gbphy_drv = to_gbphy_driver(dev->driver);
+	struct gbphy_device *gbphy_dev = to_gbphy_dev(dev);
+
+	gbphy_drv->remove(gbphy_dev);
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_suspended(dev);
+	pm_runtime_put_noidle(dev);
+	pm_runtime_dont_use_autosuspend(dev);
+
+	return 0;
+}
+
+static struct bus_type gbphy_bus_type = {
+	.name =		"gbphy",
+	.match =	gbphy_dev_match,
+	.probe =	gbphy_dev_probe,
+	.remove =	gbphy_dev_remove,
+	.uevent =	gbphy_dev_uevent,
+};
+
+int gb_gbphy_register_driver(struct gbphy_driver *driver,
+			     struct module *owner, const char *mod_name)
+{
+	int retval;
+
+	if (greybus_disabled())
+		return -ENODEV;
+
+	driver->driver.bus = &gbphy_bus_type;
+	driver->driver.name = driver->name;
+	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(gb_gbphy_register_driver);
+
+void gb_gbphy_deregister_driver(struct gbphy_driver *driver)
+{
+	driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL_GPL(gb_gbphy_deregister_driver);
+
+static struct gbphy_device *gb_gbphy_create_dev(struct gb_bundle *bundle,
+				struct greybus_descriptor_cport *cport_desc)
+{
+	struct gbphy_device *gbphy_dev;
+	int retval;
+	int id;
+
+	id = ida_simple_get(&gbphy_id, 1, 0, GFP_KERNEL);
+	if (id < 0)
+		return ERR_PTR(id);
+
+	gbphy_dev = kzalloc(sizeof(*gbphy_dev), GFP_KERNEL);
+	if (!gbphy_dev) {
+		ida_simple_remove(&gbphy_id, id);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	gbphy_dev->id = id;
+	gbphy_dev->bundle = bundle;
+	gbphy_dev->cport_desc = cport_desc;
+	gbphy_dev->dev.parent = &bundle->dev;
+	gbphy_dev->dev.bus = &gbphy_bus_type;
+	gbphy_dev->dev.type = &greybus_gbphy_dev_type;
+	gbphy_dev->dev.groups = gbphy_dev_groups;
+	gbphy_dev->dev.dma_mask = bundle->dev.dma_mask;
+	dev_set_name(&gbphy_dev->dev, "gbphy%d", id);
+
+	retval = device_register(&gbphy_dev->dev);
+	if (retval) {
+		put_device(&gbphy_dev->dev);
+		return ERR_PTR(retval);
+	}
+
+	return gbphy_dev;
+}
+
+static void gb_gbphy_disconnect(struct gb_bundle *bundle)
+{
+	struct gbphy_host *gbphy_host = greybus_get_drvdata(bundle);
+	struct gbphy_device *gbphy_dev, *temp;
+	int ret;
+
+	ret = gb_pm_runtime_get_sync(bundle);
+	if (ret < 0)
+		gb_pm_runtime_get_noresume(bundle);
+
+	list_for_each_entry_safe(gbphy_dev, temp, &gbphy_host->devices, list) {
+		list_del(&gbphy_dev->list);
+		device_unregister(&gbphy_dev->dev);
+	}
+
+	kfree(gbphy_host);
+}
+
+static int gb_gbphy_probe(struct gb_bundle *bundle,
+			  const struct greybus_bundle_id *id)
+{
+	struct gbphy_host *gbphy_host;
+	struct gbphy_device *gbphy_dev;
+	int i;
+
+	if (bundle->num_cports == 0)
+		return -ENODEV;
+
+	gbphy_host = kzalloc(sizeof(*gbphy_host), GFP_KERNEL);
+	if (!gbphy_host)
+		return -ENOMEM;
+
+	gbphy_host->bundle = bundle;
+	INIT_LIST_HEAD(&gbphy_host->devices);
+	greybus_set_drvdata(bundle, gbphy_host);
+
+	/*
+	 * Create a bunch of children devices, one per cport, and bind the
+	 * bridged phy drivers to them.
+	 */
+	for (i = 0; i < bundle->num_cports; ++i) {
+		gbphy_dev = gb_gbphy_create_dev(bundle, &bundle->cport_desc[i]);
+		if (IS_ERR(gbphy_dev)) {
+			gb_gbphy_disconnect(bundle);
+			return PTR_ERR(gbphy_dev);
+		}
+		list_add(&gbphy_dev->list, &gbphy_host->devices);
+	}
+
+	gb_pm_runtime_put_autosuspend(bundle);
+
+	return 0;
+}
+
+static const struct greybus_bundle_id gb_gbphy_id_table[] = {
+	{ GREYBUS_DEVICE_CLASS(GREYBUS_CLASS_BRIDGED_PHY) },
+	{ },
+};
+MODULE_DEVICE_TABLE(greybus, gb_gbphy_id_table);
+
+static struct greybus_driver gb_gbphy_driver = {
+	.name		= "gbphy",
+	.probe		= gb_gbphy_probe,
+	.disconnect	= gb_gbphy_disconnect,
+	.id_table	= gb_gbphy_id_table,
+};
+
+static int __init gbphy_init(void)
+{
+	int retval;
+
+	retval = bus_register(&gbphy_bus_type);
+	if (retval) {
+		pr_err("gbphy bus register failed (%d)\n", retval);
+		return retval;
+	}
+
+	retval = greybus_register(&gb_gbphy_driver);
+	if (retval) {
+		pr_err("error registering greybus driver\n");
+		goto error_gbphy;
+	}
+
+	return 0;
+
+error_gbphy:
+	bus_unregister(&gbphy_bus_type);
+	ida_destroy(&gbphy_id);
+	return retval;
+}
+module_init(gbphy_init);
+
+static void __exit gbphy_exit(void)
+{
+	greybus_deregister(&gb_gbphy_driver);
+	bus_unregister(&gbphy_bus_type);
+	ida_destroy(&gbphy_id);
+}
+module_exit(gbphy_exit);
+
+MODULE_LICENSE("GPL v2");