1/*
2 * Intel MIC Platform Software Stack (MPSS)
3 *
4 * Copyright(c) 2014 Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2, as
8 * published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * The full GNU General Public License is included in this distribution in
16 * the file called "COPYING".
17 *
18 * Intel MIC Bus driver.
19 *
20 * This implementation is very similar to the the virtio bus driver
21 * implementation @ drivers/virtio/virtio.c
22 */
23#include <linux/slab.h>
24#include <linux/module.h>
25#include <linux/idr.h>
26#include <linux/mic_bus.h>
27
28static ssize_t device_show(struct device *d,
29			   struct device_attribute *attr, char *buf)
30{
31	struct mbus_device *dev = dev_to_mbus(d);
32	return sprintf(buf, "0x%04x\n", dev->id.device);
33}
34static DEVICE_ATTR_RO(device);
35
36static ssize_t vendor_show(struct device *d,
37			   struct device_attribute *attr, char *buf)
38{
39	struct mbus_device *dev = dev_to_mbus(d);
40	return sprintf(buf, "0x%04x\n", dev->id.vendor);
41}
42static DEVICE_ATTR_RO(vendor);
43
44static ssize_t modalias_show(struct device *d,
45			     struct device_attribute *attr, char *buf)
46{
47	struct mbus_device *dev = dev_to_mbus(d);
48	return sprintf(buf, "mbus:d%08Xv%08X\n",
49		       dev->id.device, dev->id.vendor);
50}
51static DEVICE_ATTR_RO(modalias);
52
53static struct attribute *mbus_dev_attrs[] = {
54	&dev_attr_device.attr,
55	&dev_attr_vendor.attr,
56	&dev_attr_modalias.attr,
57	NULL,
58};
59ATTRIBUTE_GROUPS(mbus_dev);
60
61static inline int mbus_id_match(const struct mbus_device *dev,
62				const struct mbus_device_id *id)
63{
64	if (id->device != dev->id.device && id->device != MBUS_DEV_ANY_ID)
65		return 0;
66
67	return id->vendor == MBUS_DEV_ANY_ID || id->vendor == dev->id.vendor;
68}
69
70/*
71 * This looks through all the IDs a driver claims to support.  If any of them
72 * match, we return 1 and the kernel will call mbus_dev_probe().
73 */
74static int mbus_dev_match(struct device *dv, struct device_driver *dr)
75{
76	unsigned int i;
77	struct mbus_device *dev = dev_to_mbus(dv);
78	const struct mbus_device_id *ids;
79
80	ids = drv_to_mbus(dr)->id_table;
81	for (i = 0; ids[i].device; i++)
82		if (mbus_id_match(dev, &ids[i]))
83			return 1;
84	return 0;
85}
86
87static int mbus_uevent(struct device *dv, struct kobj_uevent_env *env)
88{
89	struct mbus_device *dev = dev_to_mbus(dv);
90
91	return add_uevent_var(env, "MODALIAS=mbus:d%08Xv%08X",
92			      dev->id.device, dev->id.vendor);
93}
94
95static int mbus_dev_probe(struct device *d)
96{
97	int err;
98	struct mbus_device *dev = dev_to_mbus(d);
99	struct mbus_driver *drv = drv_to_mbus(dev->dev.driver);
100
101	err = drv->probe(dev);
102	if (!err)
103		if (drv->scan)
104			drv->scan(dev);
105	return err;
106}
107
108static int mbus_dev_remove(struct device *d)
109{
110	struct mbus_device *dev = dev_to_mbus(d);
111	struct mbus_driver *drv = drv_to_mbus(dev->dev.driver);
112
113	drv->remove(dev);
114	return 0;
115}
116
117static struct bus_type mic_bus = {
118	.name  = "mic_bus",
119	.match = mbus_dev_match,
120	.dev_groups = mbus_dev_groups,
121	.uevent = mbus_uevent,
122	.probe = mbus_dev_probe,
123	.remove = mbus_dev_remove,
124};
125
126int mbus_register_driver(struct mbus_driver *driver)
127{
128	driver->driver.bus = &mic_bus;
129	return driver_register(&driver->driver);
130}
131EXPORT_SYMBOL_GPL(mbus_register_driver);
132
133void mbus_unregister_driver(struct mbus_driver *driver)
134{
135	driver_unregister(&driver->driver);
136}
137EXPORT_SYMBOL_GPL(mbus_unregister_driver);
138
139static void mbus_release_dev(struct device *d)
140{
141	struct mbus_device *mbdev = dev_to_mbus(d);
142	kfree(mbdev);
143}
144
145struct mbus_device *
146mbus_register_device(struct device *pdev, int id, struct dma_map_ops *dma_ops,
147		     struct mbus_hw_ops *hw_ops, int index,
148		     void __iomem *mmio_va)
149{
150	int ret;
151	struct mbus_device *mbdev;
152
153	mbdev = kzalloc(sizeof(*mbdev), GFP_KERNEL);
154	if (!mbdev)
155		return ERR_PTR(-ENOMEM);
156
157	mbdev->mmio_va = mmio_va;
158	mbdev->dev.parent = pdev;
159	mbdev->id.device = id;
160	mbdev->id.vendor = MBUS_DEV_ANY_ID;
161	mbdev->dev.archdata.dma_ops = dma_ops;
162	mbdev->dev.dma_mask = &mbdev->dev.coherent_dma_mask;
163	dma_set_mask(&mbdev->dev, DMA_BIT_MASK(64));
164	mbdev->dev.release = mbus_release_dev;
165	mbdev->hw_ops = hw_ops;
166	mbdev->dev.bus = &mic_bus;
167	mbdev->index = index;
168	dev_set_name(&mbdev->dev, "mbus-dev%u", mbdev->index);
169	/*
170	 * device_register() causes the bus infrastructure to look for a
171	 * matching driver.
172	 */
173	ret = device_register(&mbdev->dev);
174	if (ret)
175		goto free_mbdev;
176	return mbdev;
177free_mbdev:
178	put_device(&mbdev->dev);
179	return ERR_PTR(ret);
180}
181EXPORT_SYMBOL_GPL(mbus_register_device);
182
183void mbus_unregister_device(struct mbus_device *mbdev)
184{
185	device_unregister(&mbdev->dev);
186}
187EXPORT_SYMBOL_GPL(mbus_unregister_device);
188
189static int __init mbus_init(void)
190{
191	return bus_register(&mic_bus);
192}
193
194static void __exit mbus_exit(void)
195{
196	bus_unregister(&mic_bus);
197}
198
199core_initcall(mbus_init);
200module_exit(mbus_exit);
201
202MODULE_AUTHOR("Intel Corporation");
203MODULE_DESCRIPTION("Intel(R) MIC Bus driver");
204MODULE_LICENSE("GPL v2");
205