1 files changed, 230 insertions, 0 deletions
diff --git a/drivers/thunderbolt/domain.c b/drivers/thunderbolt/domain.c
new file mode 100644
index 000000000000..3302f4c59638
--- /dev/null
+++ b/drivers/thunderbolt/domain.c
@@ -0,0 +1,230 @@
+/*
+ * Thunderbolt bus support
+ *
+ * Copyright (C) 2017, Intel Corporation
+ * Author:  Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "tb.h"
+
+static DEFINE_IDA(tb_domain_ida);
+
+struct bus_type tb_bus_type = {
+	.name = "thunderbolt",
+};
+
+static void tb_domain_release(struct device *dev)
+{
+	struct tb *tb = container_of(dev, struct tb, dev);
+
+	tb_ctl_free(tb->ctl);
+	destroy_workqueue(tb->wq);
+	ida_simple_remove(&tb_domain_ida, tb->index);
+	mutex_destroy(&tb->lock);
+	kfree(tb);
+}
+
+struct device_type tb_domain_type = {
+	.name = "thunderbolt_domain",
+	.release = tb_domain_release,
+};
+
+/**
+ * tb_domain_alloc() - Allocate a domain
+ * @nhi: Pointer to the host controller
+ * @privsize: Size of the connection manager private data
+ *
+ * Allocates and initializes a new Thunderbolt domain. Connection
+ * managers are expected to call this and then fill in @cm_ops
+ * accordingly.
+ *
+ * Call tb_domain_put() to release the domain before it has been added
+ * to the system.
+ *
+ * Return: allocated domain structure on %NULL in case of error
+ */
+struct tb *tb_domain_alloc(struct tb_nhi *nhi, size_t privsize)
+{
+	struct tb *tb;
+
+	/*
+	 * Make sure the structure sizes map with that the hardware
+	 * expects because bit-fields are being used.
+	 */
+	BUILD_BUG_ON(sizeof(struct tb_regs_switch_header) != 5 * 4);
+	BUILD_BUG_ON(sizeof(struct tb_regs_port_header) != 8 * 4);
+	BUILD_BUG_ON(sizeof(struct tb_regs_hop) != 2 * 4);
+
+	tb = kzalloc(sizeof(*tb) + privsize, GFP_KERNEL);
+	if (!tb)
+		return NULL;
+
+	tb->nhi = nhi;
+	mutex_init(&tb->lock);
+
+	tb->index = ida_simple_get(&tb_domain_ida, 0, 0, GFP_KERNEL);
+	if (tb->index < 0)
+		goto err_free;
+
+	tb->wq = alloc_ordered_workqueue("thunderbolt%d", 0, tb->index);
+	if (!tb->wq)
+		goto err_remove_ida;
+
+	tb->dev.parent = &nhi->pdev->dev;
+	tb->dev.bus = &tb_bus_type;
+	tb->dev.type = &tb_domain_type;
+	dev_set_name(&tb->dev, "domain%d", tb->index);
+	device_initialize(&tb->dev);
+
+	return tb;
+
+err_remove_ida:
+	ida_simple_remove(&tb_domain_ida, tb->index);
+err_free:
+	kfree(tb);
+
+	return NULL;
+}
+
+/**
+ * tb_domain_add() - Add domain to the system
+ * @tb: Domain to add
+ *
+ * Starts the domain and adds it to the system. Hotplugging devices will
+ * work after this has been returned successfully. In order to remove
+ * and release the domain after this function has been called, call
+ * tb_domain_remove().
+ *
+ * Return: %0 in case of success and negative errno in case of error
+ */
+int tb_domain_add(struct tb *tb)
+{
+	int ret;
+
+	if (WARN_ON(!tb->cm_ops))
+		return -EINVAL;
+
+	mutex_lock(&tb->lock);
+
+	tb->ctl = tb_ctl_alloc(tb->nhi, tb->cm_ops->hotplug, tb);
+	if (!tb->ctl) {
+		ret = -ENOMEM;
+		goto err_unlock;
+	}
+
+	/*
+	 * tb_schedule_hotplug_handler may be called as soon as the config
+	 * channel is started. Thats why we have to hold the lock here.
+	 */
+	tb_ctl_start(tb->ctl);
+
+	ret = device_add(&tb->dev);
+	if (ret)
+		goto err_ctl_stop;
+
+	/* Start the domain */
+	if (tb->cm_ops->start) {
+		ret = tb->cm_ops->start(tb);
+		if (ret)
+			goto err_domain_del;
+	}
+
+	/* This starts event processing */
+	mutex_unlock(&tb->lock);
+
+	return 0;
+
+err_domain_del:
+	device_del(&tb->dev);
+err_ctl_stop:
+	tb_ctl_stop(tb->ctl);
+err_unlock:
+	mutex_unlock(&tb->lock);
+
+	return ret;
+}
+
+/**
+ * tb_domain_remove() - Removes and releases a domain
+ * @tb: Domain to remove
+ *
+ * Stops the domain, removes it from the system and releases all
+ * resources once the last reference has been released.
+ */
+void tb_domain_remove(struct tb *tb)
+{
+	mutex_lock(&tb->lock);
+	if (tb->cm_ops->stop)
+		tb->cm_ops->stop(tb);
+	/* Stop the domain control traffic */
+	tb_ctl_stop(tb->ctl);
+	mutex_unlock(&tb->lock);
+
+	flush_workqueue(tb->wq);
+	device_unregister(&tb->dev);
+}
+
+/**
+ * tb_domain_suspend_noirq() - Suspend a domain
+ * @tb: Domain to suspend
+ *
+ * Suspends all devices in the domain and stops the control channel.
+ */
+int tb_domain_suspend_noirq(struct tb *tb)
+{
+	int ret = 0;
+
+	/*
+	 * The control channel interrupt is left enabled during suspend
+	 * and taking the lock here prevents any events happening before
+	 * we actually have stopped the domain and the control channel.
+	 */
+	mutex_lock(&tb->lock);
+	if (tb->cm_ops->suspend_noirq)
+		ret = tb->cm_ops->suspend_noirq(tb);
+	if (!ret)
+		tb_ctl_stop(tb->ctl);
+	mutex_unlock(&tb->lock);
+
+	return ret;
+}
+
+/**
+ * tb_domain_resume_noirq() - Resume a domain
+ * @tb: Domain to resume
+ *
+ * Re-starts the control channel, and resumes all devices connected to
+ * the domain.
+ */
+int tb_domain_resume_noirq(struct tb *tb)
+{
+	int ret = 0;
+
+	mutex_lock(&tb->lock);
+	tb_ctl_start(tb->ctl);
+	if (tb->cm_ops->resume_noirq)
+		ret = tb->cm_ops->resume_noirq(tb);
+	mutex_unlock(&tb->lock);
+
+	return ret;
+}
+
+int tb_domain_init(void)
+{
+	return bus_register(&tb_bus_type);
+}
+
+void tb_domain_exit(void)
+{
+	bus_unregister(&tb_bus_type);
+	ida_destroy(&tb_domain_ida);
+}