tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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
28/* Unique numbering for mbus devices. */
29static DEFINE_IDA(mbus_index_ida);
30
31static ssize_t device_show(struct device *d,
32 struct device_attribute *attr, char *buf)
33{
34 struct mbus_device *dev = dev_to_mbus(d);
35 return sprintf(buf, "0x%04x\n", dev->id.device);
36}
37static DEVICE_ATTR_RO(device);
38
39static ssize_t vendor_show(struct device *d,
40 struct device_attribute *attr, char *buf)
41{
42 struct mbus_device *dev = dev_to_mbus(d);
43 return sprintf(buf, "0x%04x\n", dev->id.vendor);
44}
45static DEVICE_ATTR_RO(vendor);
46
47static ssize_t modalias_show(struct device *d,
48 struct device_attribute *attr, char *buf)
49{
50 struct mbus_device *dev = dev_to_mbus(d);
51 return sprintf(buf, "mbus:d%08Xv%08X\n",
52 dev->id.device, dev->id.vendor);
53}
54static DEVICE_ATTR_RO(modalias);
55
56static struct attribute *mbus_dev_attrs[] = {
57 &dev_attr_device.attr,
58 &dev_attr_vendor.attr,
59 &dev_attr_modalias.attr,
60 NULL,
61};
62ATTRIBUTE_GROUPS(mbus_dev);
63
64static inline int mbus_id_match(const struct mbus_device *dev,
65 const struct mbus_device_id *id)
66{
67 if (id->device != dev->id.device && id->device != MBUS_DEV_ANY_ID)
68 return 0;
69
70 return id->vendor == MBUS_DEV_ANY_ID || id->vendor == dev->id.vendor;
71}
72
73/*
74 * This looks through all the IDs a driver claims to support. If any of them
75 * match, we return 1 and the kernel will call mbus_dev_probe().
76 */
77static int mbus_dev_match(struct device *dv, struct device_driver *dr)
78{
79 unsigned int i;
80 struct mbus_device *dev = dev_to_mbus(dv);
81 const struct mbus_device_id *ids;
82
83 ids = drv_to_mbus(dr)->id_table;
84 for (i = 0; ids[i].device; i++)
85 if (mbus_id_match(dev, &ids[i]))
86 return 1;
87 return 0;
88}
89
90static int mbus_uevent(struct device *dv, struct kobj_uevent_env *env)
91{
92 struct mbus_device *dev = dev_to_mbus(dv);
93
94 return add_uevent_var(env, "MODALIAS=mbus:d%08Xv%08X",
95 dev->id.device, dev->id.vendor);
96}
97
98static int mbus_dev_probe(struct device *d)
99{
100 int err;
101 struct mbus_device *dev = dev_to_mbus(d);
102 struct mbus_driver *drv = drv_to_mbus(dev->dev.driver);
103
104 err = drv->probe(dev);
105 if (!err)
106 if (drv->scan)
107 drv->scan(dev);
108 return err;
109}
110
111static int mbus_dev_remove(struct device *d)
112{
113 struct mbus_device *dev = dev_to_mbus(d);
114 struct mbus_driver *drv = drv_to_mbus(dev->dev.driver);
115
116 drv->remove(dev);
117 return 0;
118}
119
120static struct bus_type mic_bus = {
121 .name = "mic_bus",
122 .match = mbus_dev_match,
123 .dev_groups = mbus_dev_groups,
124 .uevent = mbus_uevent,
125 .probe = mbus_dev_probe,
126 .remove = mbus_dev_remove,
127};
128
129int mbus_register_driver(struct mbus_driver *driver)
130{
131 driver->driver.bus = &mic_bus;
132 return driver_register(&driver->driver);
133}
134EXPORT_SYMBOL_GPL(mbus_register_driver);
135
136void mbus_unregister_driver(struct mbus_driver *driver)
137{
138 driver_unregister(&driver->driver);
139}
140EXPORT_SYMBOL_GPL(mbus_unregister_driver);
141
142static void mbus_release_dev(struct device *d)
143{
144 struct mbus_device *mbdev = dev_to_mbus(d);
145 kfree(mbdev);
146}
147
148struct mbus_device *
149mbus_register_device(struct device *pdev, int id, struct dma_map_ops *dma_ops,
150 struct mbus_hw_ops *hw_ops, void __iomem *mmio_va)
151{
152 int ret;
153 struct mbus_device *mbdev;
154
155 mbdev = kzalloc(sizeof(*mbdev), GFP_KERNEL);
156 if (!mbdev)
157 return ERR_PTR(-ENOMEM);
158
159 mbdev->mmio_va = mmio_va;
160 mbdev->dev.parent = pdev;
161 mbdev->id.device = id;
162 mbdev->id.vendor = MBUS_DEV_ANY_ID;
163 mbdev->dev.archdata.dma_ops = dma_ops;
164 mbdev->dev.dma_mask = &mbdev->dev.coherent_dma_mask;
165 dma_set_mask(&mbdev->dev, DMA_BIT_MASK(64));
166 mbdev->dev.release = mbus_release_dev;
167 mbdev->hw_ops = hw_ops;
168 mbdev->dev.bus = &mic_bus;
169
170 /* Assign a unique device index and hence name. */
171 ret = ida_simple_get(&mbus_index_ida, 0, 0, GFP_KERNEL);
172 if (ret < 0)
173 goto free_mbdev;
174
175 mbdev->index = ret;
176 dev_set_name(&mbdev->dev, "mbus-dev%u", mbdev->index);
177 /*
178 * device_register() causes the bus infrastructure to look for a
179 * matching driver.
180 */
181 ret = device_register(&mbdev->dev);
182 if (ret)
183 goto ida_remove;
184 return mbdev;
185ida_remove:
186 ida_simple_remove(&mbus_index_ida, mbdev->index);
187free_mbdev:
188 kfree(mbdev);
189 return ERR_PTR(ret);
190}
191EXPORT_SYMBOL_GPL(mbus_register_device);
192
193void mbus_unregister_device(struct mbus_device *mbdev)
194{
195 int index = mbdev->index; /* save for after device release */
196
197 device_unregister(&mbdev->dev);
198 ida_simple_remove(&mbus_index_ida, index);
199}
200EXPORT_SYMBOL_GPL(mbus_unregister_device);
201
202static int __init mbus_init(void)
203{
204 return bus_register(&mic_bus);
205}
206
207static void __exit mbus_exit(void)
208{
209 bus_unregister(&mic_bus);
210 ida_destroy(&mbus_index_ida);
211}
212
213core_initcall(mbus_init);
214module_exit(mbus_exit);
215
216MODULE_AUTHOR("Intel Corporation");
217MODULE_DESCRIPTION("Intel(R) MIC Bus driver");
218MODULE_LICENSE("GPL v2");