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8#include <linux/fpga/fpga-bridge.h>
9#include <linux/idr.h>
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/of_platform.h>
13#include <linux/slab.h>
14#include <linux/spinlock.h>
15
16static DEFINE_IDA(fpga_bridge_ida);
17static struct class *fpga_bridge_class;
18
19
20static DEFINE_SPINLOCK(bridge_list_lock);
21
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28
29int fpga_bridge_enable(struct fpga_bridge *bridge)
30{
31 dev_dbg(&bridge->dev, "enable\n");
32
33 if (bridge->br_ops && bridge->br_ops->enable_set)
34 return bridge->br_ops->enable_set(bridge, 1);
35
36 return 0;
37}
38EXPORT_SYMBOL_GPL(fpga_bridge_enable);
39
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45
46
47int fpga_bridge_disable(struct fpga_bridge *bridge)
48{
49 dev_dbg(&bridge->dev, "disable\n");
50
51 if (bridge->br_ops && bridge->br_ops->enable_set)
52 return bridge->br_ops->enable_set(bridge, 0);
53
54 return 0;
55}
56EXPORT_SYMBOL_GPL(fpga_bridge_disable);
57
58static struct fpga_bridge *__fpga_bridge_get(struct device *dev,
59 struct fpga_image_info *info)
60{
61 struct fpga_bridge *bridge;
62 int ret = -ENODEV;
63
64 bridge = to_fpga_bridge(dev);
65
66 bridge->info = info;
67
68 if (!mutex_trylock(&bridge->mutex)) {
69 ret = -EBUSY;
70 goto err_dev;
71 }
72
73 if (!try_module_get(dev->parent->driver->owner))
74 goto err_ll_mod;
75
76 dev_dbg(&bridge->dev, "get\n");
77
78 return bridge;
79
80err_ll_mod:
81 mutex_unlock(&bridge->mutex);
82err_dev:
83 put_device(dev);
84 return ERR_PTR(ret);
85}
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96
97struct fpga_bridge *of_fpga_bridge_get(struct device_node *np,
98 struct fpga_image_info *info)
99{
100 struct device *dev;
101
102 dev = class_find_device_by_of_node(fpga_bridge_class, np);
103 if (!dev)
104 return ERR_PTR(-ENODEV);
105
106 return __fpga_bridge_get(dev, info);
107}
108EXPORT_SYMBOL_GPL(of_fpga_bridge_get);
109
110static int fpga_bridge_dev_match(struct device *dev, const void *data)
111{
112 return dev->parent == data;
113}
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123
124struct fpga_bridge *fpga_bridge_get(struct device *dev,
125 struct fpga_image_info *info)
126{
127 struct device *bridge_dev;
128
129 bridge_dev = class_find_device(fpga_bridge_class, NULL, dev,
130 fpga_bridge_dev_match);
131 if (!bridge_dev)
132 return ERR_PTR(-ENODEV);
133
134 return __fpga_bridge_get(bridge_dev, info);
135}
136EXPORT_SYMBOL_GPL(fpga_bridge_get);
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142
143void fpga_bridge_put(struct fpga_bridge *bridge)
144{
145 dev_dbg(&bridge->dev, "put\n");
146
147 bridge->info = NULL;
148 module_put(bridge->dev.parent->driver->owner);
149 mutex_unlock(&bridge->mutex);
150 put_device(&bridge->dev);
151}
152EXPORT_SYMBOL_GPL(fpga_bridge_put);
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161
162int fpga_bridges_enable(struct list_head *bridge_list)
163{
164 struct fpga_bridge *bridge;
165 int ret;
166
167 list_for_each_entry(bridge, bridge_list, node) {
168 ret = fpga_bridge_enable(bridge);
169 if (ret)
170 return ret;
171 }
172
173 return 0;
174}
175EXPORT_SYMBOL_GPL(fpga_bridges_enable);
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186int fpga_bridges_disable(struct list_head *bridge_list)
187{
188 struct fpga_bridge *bridge;
189 int ret;
190
191 list_for_each_entry(bridge, bridge_list, node) {
192 ret = fpga_bridge_disable(bridge);
193 if (ret)
194 return ret;
195 }
196
197 return 0;
198}
199EXPORT_SYMBOL_GPL(fpga_bridges_disable);
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209void fpga_bridges_put(struct list_head *bridge_list)
210{
211 struct fpga_bridge *bridge, *next;
212 unsigned long flags;
213
214 list_for_each_entry_safe(bridge, next, bridge_list, node) {
215 fpga_bridge_put(bridge);
216
217 spin_lock_irqsave(&bridge_list_lock, flags);
218 list_del(&bridge->node);
219 spin_unlock_irqrestore(&bridge_list_lock, flags);
220 }
221}
222EXPORT_SYMBOL_GPL(fpga_bridges_put);
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234
235int of_fpga_bridge_get_to_list(struct device_node *np,
236 struct fpga_image_info *info,
237 struct list_head *bridge_list)
238{
239 struct fpga_bridge *bridge;
240 unsigned long flags;
241
242 bridge = of_fpga_bridge_get(np, info);
243 if (IS_ERR(bridge))
244 return PTR_ERR(bridge);
245
246 spin_lock_irqsave(&bridge_list_lock, flags);
247 list_add(&bridge->node, bridge_list);
248 spin_unlock_irqrestore(&bridge_list_lock, flags);
249
250 return 0;
251}
252EXPORT_SYMBOL_GPL(of_fpga_bridge_get_to_list);
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264
265int fpga_bridge_get_to_list(struct device *dev,
266 struct fpga_image_info *info,
267 struct list_head *bridge_list)
268{
269 struct fpga_bridge *bridge;
270 unsigned long flags;
271
272 bridge = fpga_bridge_get(dev, info);
273 if (IS_ERR(bridge))
274 return PTR_ERR(bridge);
275
276 spin_lock_irqsave(&bridge_list_lock, flags);
277 list_add(&bridge->node, bridge_list);
278 spin_unlock_irqrestore(&bridge_list_lock, flags);
279
280 return 0;
281}
282EXPORT_SYMBOL_GPL(fpga_bridge_get_to_list);
283
284static ssize_t name_show(struct device *dev,
285 struct device_attribute *attr, char *buf)
286{
287 struct fpga_bridge *bridge = to_fpga_bridge(dev);
288
289 return sprintf(buf, "%s\n", bridge->name);
290}
291
292static ssize_t state_show(struct device *dev,
293 struct device_attribute *attr, char *buf)
294{
295 struct fpga_bridge *bridge = to_fpga_bridge(dev);
296 int enable = 1;
297
298 if (bridge->br_ops && bridge->br_ops->enable_show)
299 enable = bridge->br_ops->enable_show(bridge);
300
301 return sprintf(buf, "%s\n", enable ? "enabled" : "disabled");
302}
303
304static DEVICE_ATTR_RO(name);
305static DEVICE_ATTR_RO(state);
306
307static struct attribute *fpga_bridge_attrs[] = {
308 &dev_attr_name.attr,
309 &dev_attr_state.attr,
310 NULL,
311};
312ATTRIBUTE_GROUPS(fpga_bridge);
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323struct fpga_bridge *
324fpga_bridge_register(struct device *parent, const char *name,
325 const struct fpga_bridge_ops *br_ops,
326 void *priv)
327{
328 struct fpga_bridge *bridge;
329 int id, ret;
330
331 if (!br_ops) {
332 dev_err(parent, "Attempt to register without fpga_bridge_ops\n");
333 return ERR_PTR(-EINVAL);
334 }
335
336 if (!name || !strlen(name)) {
337 dev_err(parent, "Attempt to register with no name!\n");
338 return ERR_PTR(-EINVAL);
339 }
340
341 bridge = kzalloc(sizeof(*bridge), GFP_KERNEL);
342 if (!bridge)
343 return ERR_PTR(-ENOMEM);
344
345 id = ida_simple_get(&fpga_bridge_ida, 0, 0, GFP_KERNEL);
346 if (id < 0) {
347 ret = id;
348 goto error_kfree;
349 }
350
351 mutex_init(&bridge->mutex);
352 INIT_LIST_HEAD(&bridge->node);
353
354 bridge->name = name;
355 bridge->br_ops = br_ops;
356 bridge->priv = priv;
357
358 bridge->dev.groups = br_ops->groups;
359 bridge->dev.class = fpga_bridge_class;
360 bridge->dev.parent = parent;
361 bridge->dev.of_node = parent->of_node;
362 bridge->dev.id = id;
363 of_platform_populate(bridge->dev.of_node, NULL, NULL, &bridge->dev);
364
365 ret = dev_set_name(&bridge->dev, "br%d", id);
366 if (ret)
367 goto error_device;
368
369 ret = device_register(&bridge->dev);
370 if (ret) {
371 put_device(&bridge->dev);
372 return ERR_PTR(ret);
373 }
374
375 return bridge;
376
377error_device:
378 ida_simple_remove(&fpga_bridge_ida, id);
379error_kfree:
380 kfree(bridge);
381
382 return ERR_PTR(ret);
383}
384EXPORT_SYMBOL_GPL(fpga_bridge_register);
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393void fpga_bridge_unregister(struct fpga_bridge *bridge)
394{
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399 if (bridge->br_ops && bridge->br_ops->fpga_bridge_remove)
400 bridge->br_ops->fpga_bridge_remove(bridge);
401
402 device_unregister(&bridge->dev);
403}
404EXPORT_SYMBOL_GPL(fpga_bridge_unregister);
405
406static void fpga_bridge_dev_release(struct device *dev)
407{
408 struct fpga_bridge *bridge = to_fpga_bridge(dev);
409
410 ida_simple_remove(&fpga_bridge_ida, bridge->dev.id);
411 kfree(bridge);
412}
413
414static int __init fpga_bridge_dev_init(void)
415{
416 fpga_bridge_class = class_create(THIS_MODULE, "fpga_bridge");
417 if (IS_ERR(fpga_bridge_class))
418 return PTR_ERR(fpga_bridge_class);
419
420 fpga_bridge_class->dev_groups = fpga_bridge_groups;
421 fpga_bridge_class->dev_release = fpga_bridge_dev_release;
422
423 return 0;
424}
425
426static void __exit fpga_bridge_dev_exit(void)
427{
428 class_destroy(fpga_bridge_class);
429 ida_destroy(&fpga_bridge_ida);
430}
431
432MODULE_DESCRIPTION("FPGA Bridge Driver");
433MODULE_AUTHOR("Alan Tull <atull@kernel.org>");
434MODULE_LICENSE("GPL v2");
435
436subsys_initcall(fpga_bridge_dev_init);
437module_exit(fpga_bridge_dev_exit);
438