1 /*
2  * Intel MIC Platform Software Stack (MPSS)
3  *
4  * Copyright(c) 2015 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 COSM Bus Driver
19  */
20 #include <linux/slab.h>
21 #include <linux/module.h>
22 #include <linux/idr.h>
23 #include "cosm_bus.h"
24 
25 /* Unique numbering for cosm devices. */
26 static DEFINE_IDA(cosm_index_ida);
27 
cosm_dev_probe(struct device * d)28 static int cosm_dev_probe(struct device *d)
29 {
30 	struct cosm_device *dev = dev_to_cosm(d);
31 	struct cosm_driver *drv = drv_to_cosm(dev->dev.driver);
32 
33 	return drv->probe(dev);
34 }
35 
cosm_dev_remove(struct device * d)36 static int cosm_dev_remove(struct device *d)
37 {
38 	struct cosm_device *dev = dev_to_cosm(d);
39 	struct cosm_driver *drv = drv_to_cosm(dev->dev.driver);
40 
41 	drv->remove(dev);
42 	return 0;
43 }
44 
45 static struct bus_type cosm_bus = {
46 	.name  = "cosm_bus",
47 	.probe = cosm_dev_probe,
48 	.remove = cosm_dev_remove,
49 };
50 
cosm_register_driver(struct cosm_driver * driver)51 int cosm_register_driver(struct cosm_driver *driver)
52 {
53 	driver->driver.bus = &cosm_bus;
54 	return driver_register(&driver->driver);
55 }
56 EXPORT_SYMBOL_GPL(cosm_register_driver);
57 
cosm_unregister_driver(struct cosm_driver * driver)58 void cosm_unregister_driver(struct cosm_driver *driver)
59 {
60 	driver_unregister(&driver->driver);
61 }
62 EXPORT_SYMBOL_GPL(cosm_unregister_driver);
63 
cosm_release_dev(struct device * d)64 static inline void cosm_release_dev(struct device *d)
65 {
66 	struct cosm_device *cdev = dev_to_cosm(d);
67 
68 	kfree(cdev);
69 }
70 
71 struct cosm_device *
cosm_register_device(struct device * pdev,struct cosm_hw_ops * hw_ops)72 cosm_register_device(struct device *pdev, struct cosm_hw_ops *hw_ops)
73 {
74 	struct cosm_device *cdev;
75 	int ret;
76 
77 	cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
78 	if (!cdev)
79 		return ERR_PTR(-ENOMEM);
80 
81 	cdev->dev.parent = pdev;
82 	cdev->dev.release = cosm_release_dev;
83 	cdev->hw_ops = hw_ops;
84 	dev_set_drvdata(&cdev->dev, cdev);
85 	cdev->dev.bus = &cosm_bus;
86 
87 	/* Assign a unique device index and hence name */
88 	ret = ida_simple_get(&cosm_index_ida, 0, 0, GFP_KERNEL);
89 	if (ret < 0)
90 		goto free_cdev;
91 
92 	cdev->index = ret;
93 	cdev->dev.id = ret;
94 	dev_set_name(&cdev->dev, "cosm-dev%u", cdev->index);
95 
96 	ret = device_register(&cdev->dev);
97 	if (ret)
98 		goto ida_remove;
99 	return cdev;
100 ida_remove:
101 	ida_simple_remove(&cosm_index_ida, cdev->index);
102 free_cdev:
103 	put_device(&cdev->dev);
104 	return ERR_PTR(ret);
105 }
106 EXPORT_SYMBOL_GPL(cosm_register_device);
107 
cosm_unregister_device(struct cosm_device * dev)108 void cosm_unregister_device(struct cosm_device *dev)
109 {
110 	int index = dev->index; /* save for after device release */
111 
112 	device_unregister(&dev->dev);
113 	ida_simple_remove(&cosm_index_ida, index);
114 }
115 EXPORT_SYMBOL_GPL(cosm_unregister_device);
116 
cosm_find_cdev_by_id(int id)117 struct cosm_device *cosm_find_cdev_by_id(int id)
118 {
119 	struct device *dev = subsys_find_device_by_id(&cosm_bus, id, NULL);
120 
121 	return dev ? container_of(dev, struct cosm_device, dev) : NULL;
122 }
123 EXPORT_SYMBOL_GPL(cosm_find_cdev_by_id);
124 
cosm_init(void)125 static int __init cosm_init(void)
126 {
127 	return bus_register(&cosm_bus);
128 }
129 
cosm_exit(void)130 static void __exit cosm_exit(void)
131 {
132 	bus_unregister(&cosm_bus);
133 	ida_destroy(&cosm_index_ida);
134 }
135 
136 core_initcall(cosm_init);
137 module_exit(cosm_exit);
138 
139 MODULE_AUTHOR("Intel Corporation");
140 MODULE_DESCRIPTION("Intel(R) MIC card OS state management bus driver");
141 MODULE_LICENSE("GPL v2");
142