GNU Linux-libre 4.19.286-gnu1
[releases.git] / arch / powerpc / platforms / pseries / ibmebus.c
1 /*
2  * IBM PowerPC IBM eBus Infrastructure Support.
3  *
4  * Copyright (c) 2005 IBM Corporation
5  *  Joachim Fenkes <fenkes@de.ibm.com>
6  *  Heiko J Schick <schickhj@de.ibm.com>
7  *
8  * All rights reserved.
9  *
10  * This source code is distributed under a dual license of GPL v2.0 and OpenIB
11  * BSD.
12  *
13  * OpenIB BSD License
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions are met:
17  *
18  * Redistributions of source code must retain the above copyright notice, this
19  * list of conditions and the following disclaimer.
20  *
21  * Redistributions in binary form must reproduce the above copyright notice,
22  * this list of conditions and the following disclaimer in the documentation
23  * and/or other materials
24  * provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
27  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
30  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
33  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
34  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38
39 #include <linux/init.h>
40 #include <linux/export.h>
41 #include <linux/console.h>
42 #include <linux/kobject.h>
43 #include <linux/dma-mapping.h>
44 #include <linux/interrupt.h>
45 #include <linux/of.h>
46 #include <linux/slab.h>
47 #include <linux/stat.h>
48 #include <linux/of_platform.h>
49 #include <asm/ibmebus.h>
50
51 static struct device ibmebus_bus_device = { /* fake "parent" device */
52         .init_name = "ibmebus",
53 };
54
55 struct bus_type ibmebus_bus_type;
56
57 /* These devices will automatically be added to the bus during init */
58 static const struct of_device_id ibmebus_matches[] __initconst = {
59         { .compatible = "IBM,lhca" },
60         { .compatible = "IBM,lhea" },
61         {},
62 };
63
64 static void *ibmebus_alloc_coherent(struct device *dev,
65                                     size_t size,
66                                     dma_addr_t *dma_handle,
67                                     gfp_t flag,
68                                     unsigned long attrs)
69 {
70         void *mem;
71
72         mem = kmalloc(size, flag);
73         *dma_handle = (dma_addr_t)mem;
74
75         return mem;
76 }
77
78 static void ibmebus_free_coherent(struct device *dev,
79                                   size_t size, void *vaddr,
80                                   dma_addr_t dma_handle,
81                                   unsigned long attrs)
82 {
83         kfree(vaddr);
84 }
85
86 static dma_addr_t ibmebus_map_page(struct device *dev,
87                                    struct page *page,
88                                    unsigned long offset,
89                                    size_t size,
90                                    enum dma_data_direction direction,
91                                    unsigned long attrs)
92 {
93         return (dma_addr_t)(page_address(page) + offset);
94 }
95
96 static void ibmebus_unmap_page(struct device *dev,
97                                dma_addr_t dma_addr,
98                                size_t size,
99                                enum dma_data_direction direction,
100                                unsigned long attrs)
101 {
102         return;
103 }
104
105 static int ibmebus_map_sg(struct device *dev,
106                           struct scatterlist *sgl,
107                           int nents, enum dma_data_direction direction,
108                           unsigned long attrs)
109 {
110         struct scatterlist *sg;
111         int i;
112
113         for_each_sg(sgl, sg, nents, i) {
114                 sg->dma_address = (dma_addr_t) sg_virt(sg);
115                 sg->dma_length = sg->length;
116         }
117
118         return nents;
119 }
120
121 static void ibmebus_unmap_sg(struct device *dev,
122                              struct scatterlist *sg,
123                              int nents, enum dma_data_direction direction,
124                              unsigned long attrs)
125 {
126         return;
127 }
128
129 static int ibmebus_dma_supported(struct device *dev, u64 mask)
130 {
131         return mask == DMA_BIT_MASK(64);
132 }
133
134 static u64 ibmebus_dma_get_required_mask(struct device *dev)
135 {
136         return DMA_BIT_MASK(64);
137 }
138
139 static const struct dma_map_ops ibmebus_dma_ops = {
140         .alloc              = ibmebus_alloc_coherent,
141         .free               = ibmebus_free_coherent,
142         .map_sg             = ibmebus_map_sg,
143         .unmap_sg           = ibmebus_unmap_sg,
144         .dma_supported      = ibmebus_dma_supported,
145         .get_required_mask  = ibmebus_dma_get_required_mask,
146         .map_page           = ibmebus_map_page,
147         .unmap_page         = ibmebus_unmap_page,
148 };
149
150 static int ibmebus_match_path(struct device *dev, void *data)
151 {
152         struct device_node *dn = to_platform_device(dev)->dev.of_node;
153         return (of_find_node_by_path(data) == dn);
154 }
155
156 static int ibmebus_match_node(struct device *dev, void *data)
157 {
158         return to_platform_device(dev)->dev.of_node == data;
159 }
160
161 static int ibmebus_create_device(struct device_node *dn)
162 {
163         struct platform_device *dev;
164         int ret;
165
166         dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
167         if (!dev)
168                 return -ENOMEM;
169
170         dev->dev.bus = &ibmebus_bus_type;
171         dev->dev.dma_ops = &ibmebus_dma_ops;
172
173         ret = of_device_add(dev);
174         if (ret)
175                 platform_device_put(dev);
176         return ret;
177 }
178
179 static int ibmebus_create_devices(const struct of_device_id *matches)
180 {
181         struct device_node *root, *child;
182         struct device *dev;
183         int ret = 0;
184
185         root = of_find_node_by_path("/");
186
187         for_each_child_of_node(root, child) {
188                 if (!of_match_node(matches, child))
189                         continue;
190
191                 dev = bus_find_device(&ibmebus_bus_type, NULL, child,
192                                       ibmebus_match_node);
193                 if (dev) {
194                         put_device(dev);
195                         continue;
196                 }
197
198                 ret = ibmebus_create_device(child);
199                 if (ret) {
200                         printk(KERN_ERR "%s: failed to create device (%i)",
201                                __func__, ret);
202                         of_node_put(child);
203                         break;
204                 }
205         }
206
207         of_node_put(root);
208         return ret;
209 }
210
211 int ibmebus_register_driver(struct platform_driver *drv)
212 {
213         /* If the driver uses devices that ibmebus doesn't know, add them */
214         ibmebus_create_devices(drv->driver.of_match_table);
215
216         drv->driver.bus = &ibmebus_bus_type;
217         return driver_register(&drv->driver);
218 }
219 EXPORT_SYMBOL(ibmebus_register_driver);
220
221 void ibmebus_unregister_driver(struct platform_driver *drv)
222 {
223         driver_unregister(&drv->driver);
224 }
225 EXPORT_SYMBOL(ibmebus_unregister_driver);
226
227 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
228                         unsigned long irq_flags, const char *devname,
229                         void *dev_id)
230 {
231         unsigned int irq = irq_create_mapping(NULL, ist);
232
233         if (!irq)
234                 return -EINVAL;
235
236         return request_irq(irq, handler, irq_flags, devname, dev_id);
237 }
238 EXPORT_SYMBOL(ibmebus_request_irq);
239
240 void ibmebus_free_irq(u32 ist, void *dev_id)
241 {
242         unsigned int irq = irq_find_mapping(NULL, ist);
243
244         free_irq(irq, dev_id);
245         irq_dispose_mapping(irq);
246 }
247 EXPORT_SYMBOL(ibmebus_free_irq);
248
249 static char *ibmebus_chomp(const char *in, size_t count)
250 {
251         char *out = kmalloc(count + 1, GFP_KERNEL);
252
253         if (!out)
254                 return NULL;
255
256         memcpy(out, in, count);
257         out[count] = '\0';
258         if (out[count - 1] == '\n')
259                 out[count - 1] = '\0';
260
261         return out;
262 }
263
264 static ssize_t ibmebus_store_probe(struct bus_type *bus,
265                                    const char *buf, size_t count)
266 {
267         struct device_node *dn = NULL;
268         struct device *dev;
269         char *path;
270         ssize_t rc = 0;
271
272         path = ibmebus_chomp(buf, count);
273         if (!path)
274                 return -ENOMEM;
275
276         dev = bus_find_device(&ibmebus_bus_type, NULL, path,
277                               ibmebus_match_path);
278         if (dev) {
279                 put_device(dev);
280                 printk(KERN_WARNING "%s: %s has already been probed\n",
281                        __func__, path);
282                 rc = -EEXIST;
283                 goto out;
284         }
285
286         if ((dn = of_find_node_by_path(path))) {
287                 rc = ibmebus_create_device(dn);
288                 of_node_put(dn);
289         } else {
290                 printk(KERN_WARNING "%s: no such device node: %s\n",
291                        __func__, path);
292                 rc = -ENODEV;
293         }
294
295 out:
296         kfree(path);
297         if (rc)
298                 return rc;
299         return count;
300 }
301 static BUS_ATTR(probe, 0200, NULL, ibmebus_store_probe);
302
303 static ssize_t ibmebus_store_remove(struct bus_type *bus,
304                                     const char *buf, size_t count)
305 {
306         struct device *dev;
307         char *path;
308
309         path = ibmebus_chomp(buf, count);
310         if (!path)
311                 return -ENOMEM;
312
313         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
314                                    ibmebus_match_path))) {
315                 of_device_unregister(to_platform_device(dev));
316                 put_device(dev);
317
318                 kfree(path);
319                 return count;
320         } else {
321                 printk(KERN_WARNING "%s: %s not on the bus\n",
322                        __func__, path);
323
324                 kfree(path);
325                 return -ENODEV;
326         }
327 }
328 static BUS_ATTR(remove, 0200, NULL, ibmebus_store_remove);
329
330 static struct attribute *ibmbus_bus_attrs[] = {
331         &bus_attr_probe.attr,
332         &bus_attr_remove.attr,
333         NULL,
334 };
335 ATTRIBUTE_GROUPS(ibmbus_bus);
336
337 static int ibmebus_bus_bus_match(struct device *dev, struct device_driver *drv)
338 {
339         const struct of_device_id *matches = drv->of_match_table;
340
341         if (!matches)
342                 return 0;
343
344         return of_match_device(matches, dev) != NULL;
345 }
346
347 static int ibmebus_bus_device_probe(struct device *dev)
348 {
349         int error = -ENODEV;
350         struct platform_driver *drv;
351         struct platform_device *of_dev;
352
353         drv = to_platform_driver(dev->driver);
354         of_dev = to_platform_device(dev);
355
356         if (!drv->probe)
357                 return error;
358
359         of_dev_get(of_dev);
360
361         if (of_driver_match_device(dev, dev->driver))
362                 error = drv->probe(of_dev);
363         if (error)
364                 of_dev_put(of_dev);
365
366         return error;
367 }
368
369 static int ibmebus_bus_device_remove(struct device *dev)
370 {
371         struct platform_device *of_dev = to_platform_device(dev);
372         struct platform_driver *drv = to_platform_driver(dev->driver);
373
374         if (dev->driver && drv->remove)
375                 drv->remove(of_dev);
376         return 0;
377 }
378
379 static void ibmebus_bus_device_shutdown(struct device *dev)
380 {
381         struct platform_device *of_dev = to_platform_device(dev);
382         struct platform_driver *drv = to_platform_driver(dev->driver);
383
384         if (dev->driver && drv->shutdown)
385                 drv->shutdown(of_dev);
386 }
387
388 /*
389  * ibmebus_bus_device_attrs
390  */
391 static ssize_t devspec_show(struct device *dev,
392                                 struct device_attribute *attr, char *buf)
393 {
394         struct platform_device *ofdev;
395
396         ofdev = to_platform_device(dev);
397         return sprintf(buf, "%pOF\n", ofdev->dev.of_node);
398 }
399 static DEVICE_ATTR_RO(devspec);
400
401 static ssize_t name_show(struct device *dev,
402                                 struct device_attribute *attr, char *buf)
403 {
404         struct platform_device *ofdev;
405
406         ofdev = to_platform_device(dev);
407         return sprintf(buf, "%s\n", ofdev->dev.of_node->name);
408 }
409 static DEVICE_ATTR_RO(name);
410
411 static ssize_t modalias_show(struct device *dev,
412                                 struct device_attribute *attr, char *buf)
413 {
414         return of_device_modalias(dev, buf, PAGE_SIZE);
415 }
416 static DEVICE_ATTR_RO(modalias);
417
418 static struct attribute *ibmebus_bus_device_attrs[] = {
419         &dev_attr_devspec.attr,
420         &dev_attr_name.attr,
421         &dev_attr_modalias.attr,
422         NULL,
423 };
424 ATTRIBUTE_GROUPS(ibmebus_bus_device);
425
426 struct bus_type ibmebus_bus_type = {
427         .name      = "ibmebus",
428         .uevent    = of_device_uevent_modalias,
429         .bus_groups = ibmbus_bus_groups,
430         .match     = ibmebus_bus_bus_match,
431         .probe     = ibmebus_bus_device_probe,
432         .remove    = ibmebus_bus_device_remove,
433         .shutdown  = ibmebus_bus_device_shutdown,
434         .dev_groups = ibmebus_bus_device_groups,
435 };
436 EXPORT_SYMBOL(ibmebus_bus_type);
437
438 static int __init ibmebus_bus_init(void)
439 {
440         int err;
441
442         printk(KERN_INFO "IBM eBus Device Driver\n");
443
444         err = bus_register(&ibmebus_bus_type);
445         if (err) {
446                 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
447                        __func__);
448                 return err;
449         }
450
451         err = device_register(&ibmebus_bus_device);
452         if (err) {
453                 printk(KERN_WARNING "%s: device_register returned %i\n",
454                        __func__, err);
455                 bus_unregister(&ibmebus_bus_type);
456
457                 return err;
458         }
459
460         err = ibmebus_create_devices(ibmebus_matches);
461         if (err) {
462                 device_unregister(&ibmebus_bus_device);
463                 bus_unregister(&ibmebus_bus_type);
464                 return err;
465         }
466
467         return 0;
468 }
469 postcore_initcall(ibmebus_bus_init);