Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
[linux-2.6] / arch / powerpc / kernel / 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/console.h>
41 #include <linux/kobject.h>
42 #include <linux/dma-mapping.h>
43 #include <linux/interrupt.h>
44 #include <linux/of.h>
45 #include <linux/of_platform.h>
46 #include <asm/ibmebus.h>
47 #include <asm/abs_addr.h>
48
49 static struct device ibmebus_bus_device = { /* fake "parent" device */
50         .init_name = "ibmebus",
51 };
52
53 struct bus_type ibmebus_bus_type;
54
55 /* These devices will automatically be added to the bus during init */
56 static struct of_device_id __initdata ibmebus_matches[] = {
57         { .compatible = "IBM,lhca" },
58         { .compatible = "IBM,lhea" },
59         {},
60 };
61
62 static void *ibmebus_alloc_coherent(struct device *dev,
63                                     size_t size,
64                                     dma_addr_t *dma_handle,
65                                     gfp_t flag)
66 {
67         void *mem;
68
69         mem = kmalloc(size, flag);
70         *dma_handle = (dma_addr_t)mem;
71
72         return mem;
73 }
74
75 static void ibmebus_free_coherent(struct device *dev,
76                                   size_t size, void *vaddr,
77                                   dma_addr_t dma_handle)
78 {
79         kfree(vaddr);
80 }
81
82 static dma_addr_t ibmebus_map_page(struct device *dev,
83                                    struct page *page,
84                                    unsigned long offset,
85                                    size_t size,
86                                    enum dma_data_direction direction,
87                                    struct dma_attrs *attrs)
88 {
89         return (dma_addr_t)(page_address(page) + offset);
90 }
91
92 static void ibmebus_unmap_page(struct device *dev,
93                                dma_addr_t dma_addr,
94                                size_t size,
95                                enum dma_data_direction direction,
96                                struct dma_attrs *attrs)
97 {
98         return;
99 }
100
101 static int ibmebus_map_sg(struct device *dev,
102                           struct scatterlist *sgl,
103                           int nents, enum dma_data_direction direction,
104                           struct dma_attrs *attrs)
105 {
106         struct scatterlist *sg;
107         int i;
108
109         for_each_sg(sgl, sg, nents, i) {
110                 sg->dma_address = (dma_addr_t) sg_virt(sg);
111                 sg->dma_length = sg->length;
112         }
113
114         return nents;
115 }
116
117 static void ibmebus_unmap_sg(struct device *dev,
118                              struct scatterlist *sg,
119                              int nents, enum dma_data_direction direction,
120                              struct dma_attrs *attrs)
121 {
122         return;
123 }
124
125 static int ibmebus_dma_supported(struct device *dev, u64 mask)
126 {
127         return 1;
128 }
129
130 static struct dma_mapping_ops ibmebus_dma_ops = {
131         .alloc_coherent = ibmebus_alloc_coherent,
132         .free_coherent  = ibmebus_free_coherent,
133         .map_sg         = ibmebus_map_sg,
134         .unmap_sg       = ibmebus_unmap_sg,
135         .dma_supported  = ibmebus_dma_supported,
136         .map_page       = ibmebus_map_page,
137         .unmap_page     = ibmebus_unmap_page,
138 };
139
140 static int ibmebus_match_path(struct device *dev, void *data)
141 {
142         struct device_node *dn = to_of_device(dev)->node;
143         return (dn->full_name &&
144                 (strcasecmp((char *)data, dn->full_name) == 0));
145 }
146
147 static int ibmebus_match_node(struct device *dev, void *data)
148 {
149         return to_of_device(dev)->node == data;
150 }
151
152 static int ibmebus_create_device(struct device_node *dn)
153 {
154         struct of_device *dev;
155         int ret;
156
157         dev = of_device_alloc(dn, NULL, &ibmebus_bus_device);
158         if (!dev)
159                 return -ENOMEM;
160
161         dev->dev.bus = &ibmebus_bus_type;
162         dev->dev.archdata.dma_ops = &ibmebus_dma_ops;
163
164         ret = of_device_register(dev);
165         if (ret) {
166                 of_device_free(dev);
167                 return ret;
168         }
169
170         return 0;
171 }
172
173 static int ibmebus_create_devices(const struct of_device_id *matches)
174 {
175         struct device_node *root, *child;
176         int ret = 0;
177
178         root = of_find_node_by_path("/");
179
180         for_each_child_of_node(root, child) {
181                 if (!of_match_node(matches, child))
182                         continue;
183
184                 if (bus_find_device(&ibmebus_bus_type, NULL, child,
185                                     ibmebus_match_node))
186                         continue;
187
188                 ret = ibmebus_create_device(child);
189                 if (ret) {
190                         printk(KERN_ERR "%s: failed to create device (%i)",
191                                __func__, ret);
192                         of_node_put(child);
193                         break;
194                 }
195         }
196
197         of_node_put(root);
198         return ret;
199 }
200
201 int ibmebus_register_driver(struct of_platform_driver *drv)
202 {
203         /* If the driver uses devices that ibmebus doesn't know, add them */
204         ibmebus_create_devices(drv->match_table);
205
206         return of_register_driver(drv, &ibmebus_bus_type);
207 }
208 EXPORT_SYMBOL(ibmebus_register_driver);
209
210 void ibmebus_unregister_driver(struct of_platform_driver *drv)
211 {
212         of_unregister_driver(drv);
213 }
214 EXPORT_SYMBOL(ibmebus_unregister_driver);
215
216 int ibmebus_request_irq(u32 ist, irq_handler_t handler,
217                         unsigned long irq_flags, const char *devname,
218                         void *dev_id)
219 {
220         unsigned int irq = irq_create_mapping(NULL, ist);
221
222         if (irq == NO_IRQ)
223                 return -EINVAL;
224
225         return request_irq(irq, handler, irq_flags, devname, dev_id);
226 }
227 EXPORT_SYMBOL(ibmebus_request_irq);
228
229 void ibmebus_free_irq(u32 ist, void *dev_id)
230 {
231         unsigned int irq = irq_find_mapping(NULL, ist);
232
233         free_irq(irq, dev_id);
234         irq_dispose_mapping(irq);
235 }
236 EXPORT_SYMBOL(ibmebus_free_irq);
237
238 static char *ibmebus_chomp(const char *in, size_t count)
239 {
240         char *out = kmalloc(count + 1, GFP_KERNEL);
241
242         if (!out)
243                 return NULL;
244
245         memcpy(out, in, count);
246         out[count] = '\0';
247         if (out[count - 1] == '\n')
248                 out[count - 1] = '\0';
249
250         return out;
251 }
252
253 static ssize_t ibmebus_store_probe(struct bus_type *bus,
254                                    const char *buf, size_t count)
255 {
256         struct device_node *dn = NULL;
257         char *path;
258         ssize_t rc = 0;
259
260         path = ibmebus_chomp(buf, count);
261         if (!path)
262                 return -ENOMEM;
263
264         if (bus_find_device(&ibmebus_bus_type, NULL, path,
265                             ibmebus_match_path)) {
266                 printk(KERN_WARNING "%s: %s has already been probed\n",
267                        __func__, path);
268                 rc = -EEXIST;
269                 goto out;
270         }
271
272         if ((dn = of_find_node_by_path(path))) {
273                 rc = ibmebus_create_device(dn);
274                 of_node_put(dn);
275         } else {
276                 printk(KERN_WARNING "%s: no such device node: %s\n",
277                        __func__, path);
278                 rc = -ENODEV;
279         }
280
281 out:
282         kfree(path);
283         if (rc)
284                 return rc;
285         return count;
286 }
287
288 static ssize_t ibmebus_store_remove(struct bus_type *bus,
289                                     const char *buf, size_t count)
290 {
291         struct device *dev;
292         char *path;
293
294         path = ibmebus_chomp(buf, count);
295         if (!path)
296                 return -ENOMEM;
297
298         if ((dev = bus_find_device(&ibmebus_bus_type, NULL, path,
299                                    ibmebus_match_path))) {
300                 of_device_unregister(to_of_device(dev));
301
302                 kfree(path);
303                 return count;
304         } else {
305                 printk(KERN_WARNING "%s: %s not on the bus\n",
306                        __func__, path);
307
308                 kfree(path);
309                 return -ENODEV;
310         }
311 }
312
313 static struct bus_attribute ibmebus_bus_attrs[] = {
314         __ATTR(probe, S_IWUSR, NULL, ibmebus_store_probe),
315         __ATTR(remove, S_IWUSR, NULL, ibmebus_store_remove),
316         __ATTR_NULL
317 };
318
319 struct bus_type ibmebus_bus_type = {
320         .uevent    = of_device_uevent,
321         .bus_attrs = ibmebus_bus_attrs
322 };
323 EXPORT_SYMBOL(ibmebus_bus_type);
324
325 static int __init ibmebus_bus_init(void)
326 {
327         int err;
328
329         printk(KERN_INFO "IBM eBus Device Driver\n");
330
331         err = of_bus_type_init(&ibmebus_bus_type, "ibmebus");
332         if (err) {
333                 printk(KERN_ERR "%s: failed to register IBM eBus.\n",
334                        __func__);
335                 return err;
336         }
337
338         err = device_register(&ibmebus_bus_device);
339         if (err) {
340                 printk(KERN_WARNING "%s: device_register returned %i\n",
341                        __func__, err);
342                 bus_unregister(&ibmebus_bus_type);
343
344                 return err;
345         }
346
347         err = ibmebus_create_devices(ibmebus_matches);
348         if (err) {
349                 device_unregister(&ibmebus_bus_device);
350                 bus_unregister(&ibmebus_bus_type);
351                 return err;
352         }
353
354         return 0;
355 }
356 postcore_initcall(ibmebus_bus_init);