1 #include <linux/string.h>
2 #include <linux/kernel.h>
3 #include <linux/of.h>
4 #include <linux/of_device.h>
5 #include <linux/of_address.h>
6 #include <linux/of_iommu.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/init.h>
9 #include <linux/module.h>
10 #include <linux/mod_devicetable.h>
11 #include <linux/slab.h>
12
13 #include <asm/errno.h>
14 #include "of_private.h"
15
16 /**
17 * of_match_device - Tell if a struct device matches an of_device_id list
18 * @ids: array of of device match structures to search in
19 * @dev: the of device structure to match against
20 *
21 * Used by a driver to check whether an platform_device present in the
22 * system is in its list of supported devices.
23 */
of_match_device(const struct of_device_id * matches,const struct device * dev)24 const struct of_device_id *of_match_device(const struct of_device_id *matches,
25 const struct device *dev)
26 {
27 if ((!matches) || (!dev->of_node))
28 return NULL;
29 return of_match_node(matches, dev->of_node);
30 }
31 EXPORT_SYMBOL(of_match_device);
32
of_dev_get(struct platform_device * dev)33 struct platform_device *of_dev_get(struct platform_device *dev)
34 {
35 struct device *tmp;
36
37 if (!dev)
38 return NULL;
39 tmp = get_device(&dev->dev);
40 if (tmp)
41 return to_platform_device(tmp);
42 else
43 return NULL;
44 }
45 EXPORT_SYMBOL(of_dev_get);
46
of_dev_put(struct platform_device * dev)47 void of_dev_put(struct platform_device *dev)
48 {
49 if (dev)
50 put_device(&dev->dev);
51 }
52 EXPORT_SYMBOL(of_dev_put);
53
of_device_add(struct platform_device * ofdev)54 int of_device_add(struct platform_device *ofdev)
55 {
56 BUG_ON(ofdev->dev.of_node == NULL);
57
58 /* name and id have to be set so that the platform bus doesn't get
59 * confused on matching */
60 ofdev->name = dev_name(&ofdev->dev);
61 ofdev->id = -1;
62
63 /*
64 * If this device has not binding numa node in devicetree, that is
65 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this
66 * device is on the same node as the parent.
67 */
68 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
69
70 return device_add(&ofdev->dev);
71 }
72
73 /**
74 * of_dma_configure - Setup DMA configuration
75 * @dev: Device to apply DMA configuration
76 * @np: Pointer to OF node having DMA configuration
77 *
78 * Try to get devices's DMA configuration from DT and update it
79 * accordingly.
80 *
81 * If platform code needs to use its own special DMA configuration, it
82 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
83 * to fix up DMA configuration.
84 */
of_dma_configure(struct device * dev,struct device_node * np)85 void of_dma_configure(struct device *dev, struct device_node *np)
86 {
87 u64 dma_addr, paddr, size;
88 int ret;
89 bool coherent;
90 unsigned long offset;
91 const struct iommu_ops *iommu;
92
93 /*
94 * Set default coherent_dma_mask to 32 bit. Drivers are expected to
95 * setup the correct supported mask.
96 */
97 if (!dev->coherent_dma_mask)
98 dev->coherent_dma_mask = DMA_BIT_MASK(32);
99
100 /*
101 * Set it to coherent_dma_mask by default if the architecture
102 * code has not set it.
103 */
104 if (!dev->dma_mask)
105 dev->dma_mask = &dev->coherent_dma_mask;
106
107 ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
108 if (ret < 0) {
109 dma_addr = offset = 0;
110 size = dev->coherent_dma_mask + 1;
111 } else {
112 offset = PFN_DOWN(paddr - dma_addr);
113
114 /*
115 * Add a work around to treat the size as mask + 1 in case
116 * it is defined in DT as a mask.
117 */
118 if (size & 1) {
119 dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
120 size);
121 size = size + 1;
122 }
123
124 if (!size) {
125 dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
126 return;
127 }
128 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
129 }
130
131 dev->dma_pfn_offset = offset;
132
133 /*
134 * Limit coherent and dma mask based on size and default mask
135 * set by the driver.
136 */
137 dev->coherent_dma_mask = min(dev->coherent_dma_mask,
138 DMA_BIT_MASK(ilog2(dma_addr + size)));
139 *dev->dma_mask = min((*dev->dma_mask),
140 DMA_BIT_MASK(ilog2(dma_addr + size)));
141
142 coherent = of_dma_is_coherent(np);
143 dev_dbg(dev, "device is%sdma coherent\n",
144 coherent ? " " : " not ");
145
146 iommu = of_iommu_configure(dev, np);
147 dev_dbg(dev, "device is%sbehind an iommu\n",
148 iommu ? " " : " not ");
149
150 arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
151 }
152 EXPORT_SYMBOL_GPL(of_dma_configure);
153
of_device_register(struct platform_device * pdev)154 int of_device_register(struct platform_device *pdev)
155 {
156 device_initialize(&pdev->dev);
157 return of_device_add(pdev);
158 }
159 EXPORT_SYMBOL(of_device_register);
160
of_device_unregister(struct platform_device * ofdev)161 void of_device_unregister(struct platform_device *ofdev)
162 {
163 device_unregister(&ofdev->dev);
164 }
165 EXPORT_SYMBOL(of_device_unregister);
166
of_device_get_match_data(const struct device * dev)167 const void *of_device_get_match_data(const struct device *dev)
168 {
169 const struct of_device_id *match;
170
171 match = of_match_device(dev->driver->of_match_table, dev);
172 if (!match)
173 return NULL;
174
175 return match->data;
176 }
177 EXPORT_SYMBOL(of_device_get_match_data);
178
of_device_get_modalias(struct device * dev,char * str,ssize_t len)179 ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
180 {
181 const char *compat;
182 int cplen, i;
183 ssize_t tsize, csize, repend;
184
185 if ((!dev) || (!dev->of_node))
186 return -ENODEV;
187
188 /* Name & Type */
189 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
190 dev->of_node->type);
191
192 /* Get compatible property if any */
193 compat = of_get_property(dev->of_node, "compatible", &cplen);
194 if (!compat)
195 return csize;
196
197 /* Find true end (we tolerate multiple \0 at the end */
198 for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
199 cplen--;
200 if (!cplen)
201 return csize;
202 cplen++;
203
204 /* Check space (need cplen+1 chars including final \0) */
205 tsize = csize + cplen;
206 repend = tsize;
207
208 if (csize >= len) /* @ the limit, all is already filled */
209 return tsize;
210
211 if (tsize >= len) { /* limit compat list */
212 cplen = len - csize - 1;
213 repend = len;
214 }
215
216 /* Copy and do char replacement */
217 memcpy(&str[csize + 1], compat, cplen);
218 for (i = csize; i < repend; i++) {
219 char c = str[i];
220 if (c == '\0')
221 str[i] = 'C';
222 else if (c == ' ')
223 str[i] = '_';
224 }
225
226 return repend;
227 }
228 EXPORT_SYMBOL_GPL(of_device_get_modalias);
229
230 /**
231 * of_device_uevent - Display OF related uevent information
232 */
of_device_uevent(struct device * dev,struct kobj_uevent_env * env)233 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
234 {
235 const char *compat;
236 struct alias_prop *app;
237 int seen = 0, cplen, sl;
238
239 if ((!dev) || (!dev->of_node))
240 return;
241
242 add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
243 add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
244 if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
245 add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);
246
247 /* Since the compatible field can contain pretty much anything
248 * it's not really legal to split it out with commas. We split it
249 * up using a number of environment variables instead. */
250 compat = of_get_property(dev->of_node, "compatible", &cplen);
251 while (compat && *compat && cplen > 0) {
252 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
253 sl = strlen(compat) + 1;
254 compat += sl;
255 cplen -= sl;
256 seen++;
257 }
258 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
259
260 seen = 0;
261 mutex_lock(&of_mutex);
262 list_for_each_entry(app, &aliases_lookup, link) {
263 if (dev->of_node == app->np) {
264 add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
265 app->alias);
266 seen++;
267 }
268 }
269 mutex_unlock(&of_mutex);
270 }
271
of_device_uevent_modalias(struct device * dev,struct kobj_uevent_env * env)272 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
273 {
274 int sl;
275
276 if ((!dev) || (!dev->of_node))
277 return -ENODEV;
278
279 /* Devicetree modalias is tricky, we add it in 2 steps */
280 if (add_uevent_var(env, "MODALIAS="))
281 return -ENOMEM;
282
283 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
284 sizeof(env->buf) - env->buflen);
285 if (sl >= (sizeof(env->buf) - env->buflen))
286 return -ENOMEM;
287 env->buflen += sl;
288
289 return 0;
290 }
291 EXPORT_SYMBOL_GPL(of_device_uevent_modalias);
292