Loading...
1#include <linux/string.h>
2#include <linux/kernel.h>
3#include <linux/of.h>
4#include <linux/of_device.h>
5#include <linux/init.h>
6#include <linux/module.h>
7#include <linux/mod_devicetable.h>
8#include <linux/slab.h>
9
10#include <asm/errno.h>
11
12/**
13 * of_match_device - Tell if a struct device matches an of_device_id list
14 * @ids: array of of device match structures to search in
15 * @dev: the of device structure to match against
16 *
17 * Used by a driver to check whether an platform_device present in the
18 * system is in its list of supported devices.
19 */
20const struct of_device_id *of_match_device(const struct of_device_id *matches,
21 const struct device *dev)
22{
23 if ((!matches) || (!dev->of_node))
24 return NULL;
25 return of_match_node(matches, dev->of_node);
26}
27EXPORT_SYMBOL(of_match_device);
28
29struct platform_device *of_dev_get(struct platform_device *dev)
30{
31 struct device *tmp;
32
33 if (!dev)
34 return NULL;
35 tmp = get_device(&dev->dev);
36 if (tmp)
37 return to_platform_device(tmp);
38 else
39 return NULL;
40}
41EXPORT_SYMBOL(of_dev_get);
42
43void of_dev_put(struct platform_device *dev)
44{
45 if (dev)
46 put_device(&dev->dev);
47}
48EXPORT_SYMBOL(of_dev_put);
49
50int of_device_add(struct platform_device *ofdev)
51{
52 BUG_ON(ofdev->dev.of_node == NULL);
53
54 /* name and id have to be set so that the platform bus doesn't get
55 * confused on matching */
56 ofdev->name = dev_name(&ofdev->dev);
57 ofdev->id = -1;
58
59 /* device_add will assume that this device is on the same node as
60 * the parent. If there is no parent defined, set the node
61 * explicitly */
62 if (!ofdev->dev.parent)
63 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
64
65 return device_add(&ofdev->dev);
66}
67
68int of_device_register(struct platform_device *pdev)
69{
70 device_initialize(&pdev->dev);
71 return of_device_add(pdev);
72}
73EXPORT_SYMBOL(of_device_register);
74
75void of_device_unregister(struct platform_device *ofdev)
76{
77 device_unregister(&ofdev->dev);
78}
79EXPORT_SYMBOL(of_device_unregister);
80
81ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
82{
83 const char *compat;
84 int cplen, i;
85 ssize_t tsize, csize, repend;
86
87 /* Name & Type */
88 csize = snprintf(str, len, "of:N%sT%s", dev->of_node->name,
89 dev->of_node->type);
90
91 /* Get compatible property if any */
92 compat = of_get_property(dev->of_node, "compatible", &cplen);
93 if (!compat)
94 return csize;
95
96 /* Find true end (we tolerate multiple \0 at the end */
97 for (i = (cplen - 1); i >= 0 && !compat[i]; i--)
98 cplen--;
99 if (!cplen)
100 return csize;
101 cplen++;
102
103 /* Check space (need cplen+1 chars including final \0) */
104 tsize = csize + cplen;
105 repend = tsize;
106
107 if (csize >= len) /* @ the limit, all is already filled */
108 return tsize;
109
110 if (tsize >= len) { /* limit compat list */
111 cplen = len - csize - 1;
112 repend = len;
113 }
114
115 /* Copy and do char replacement */
116 memcpy(&str[csize + 1], compat, cplen);
117 for (i = csize; i < repend; i++) {
118 char c = str[i];
119 if (c == '\0')
120 str[i] = 'C';
121 else if (c == ' ')
122 str[i] = '_';
123 }
124
125 return tsize;
126}
127
128/**
129 * of_device_uevent - Display OF related uevent information
130 */
131int of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
132{
133 const char *compat;
134 int seen = 0, cplen, sl;
135
136 if ((!dev) || (!dev->of_node))
137 return -ENODEV;
138
139 if (add_uevent_var(env, "OF_NAME=%s", dev->of_node->name))
140 return -ENOMEM;
141
142 if (add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type))
143 return -ENOMEM;
144
145 /* Since the compatible field can contain pretty much anything
146 * it's not really legal to split it out with commas. We split it
147 * up using a number of environment variables instead. */
148
149 compat = of_get_property(dev->of_node, "compatible", &cplen);
150 while (compat && *compat && cplen > 0) {
151 if (add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat))
152 return -ENOMEM;
153
154 sl = strlen(compat) + 1;
155 compat += sl;
156 cplen -= sl;
157 seen++;
158 }
159
160 if (add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen))
161 return -ENOMEM;
162
163 /* modalias is trickier, we add it in 2 steps */
164 if (add_uevent_var(env, "MODALIAS="))
165 return -ENOMEM;
166
167 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
168 sizeof(env->buf) - env->buflen);
169 if (sl >= (sizeof(env->buf) - env->buflen))
170 return -ENOMEM;
171 env->buflen += sl;
172
173 return 0;
174}
1// SPDX-License-Identifier: GPL-2.0
2#include <linux/string.h>
3#include <linux/kernel.h>
4#include <linux/of.h>
5#include <linux/of_device.h>
6#include <linux/of_address.h>
7#include <linux/of_iommu.h>
8#include <linux/of_reserved_mem.h>
9#include <linux/dma-direct.h> /* for bus_dma_region */
10#include <linux/dma-map-ops.h>
11#include <linux/init.h>
12#include <linux/module.h>
13#include <linux/mod_devicetable.h>
14#include <linux/slab.h>
15#include <linux/platform_device.h>
16
17#include <asm/errno.h>
18#include "of_private.h"
19
20/**
21 * of_match_device - Tell if a struct device matches an of_device_id list
22 * @matches: array of of device match structures to search in
23 * @dev: the of device structure to match against
24 *
25 * Used by a driver to check whether an platform_device present in the
26 * system is in its list of supported devices.
27 */
28const struct of_device_id *of_match_device(const struct of_device_id *matches,
29 const struct device *dev)
30{
31 if (!matches || !dev->of_node || dev->of_node_reused)
32 return NULL;
33 return of_match_node(matches, dev->of_node);
34}
35EXPORT_SYMBOL(of_match_device);
36
37int of_device_add(struct platform_device *ofdev)
38{
39 BUG_ON(ofdev->dev.of_node == NULL);
40
41 /* name and id have to be set so that the platform bus doesn't get
42 * confused on matching */
43 ofdev->name = dev_name(&ofdev->dev);
44 ofdev->id = PLATFORM_DEVID_NONE;
45
46 /*
47 * If this device has not binding numa node in devicetree, that is
48 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this
49 * device is on the same node as the parent.
50 */
51 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
52
53 return device_add(&ofdev->dev);
54}
55
56static void
57of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
58{
59 struct device_node *node, *of_node = dev->of_node;
60 int count, i;
61
62 if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL))
63 return;
64
65 count = of_property_count_elems_of_size(of_node, "memory-region",
66 sizeof(u32));
67 /*
68 * If dev->of_node doesn't exist or doesn't contain memory-region, try
69 * the OF node having DMA configuration.
70 */
71 if (count <= 0) {
72 of_node = np;
73 count = of_property_count_elems_of_size(
74 of_node, "memory-region", sizeof(u32));
75 }
76
77 for (i = 0; i < count; i++) {
78 node = of_parse_phandle(of_node, "memory-region", i);
79 /*
80 * There might be multiple memory regions, but only one
81 * restricted-dma-pool region is allowed.
82 */
83 if (of_device_is_compatible(node, "restricted-dma-pool") &&
84 of_device_is_available(node)) {
85 of_node_put(node);
86 break;
87 }
88 of_node_put(node);
89 }
90
91 /*
92 * Attempt to initialize a restricted-dma-pool region if one was found.
93 * Note that count can hold a negative error code.
94 */
95 if (i < count && of_reserved_mem_device_init_by_idx(dev, of_node, i))
96 dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");
97}
98
99/**
100 * of_dma_configure_id - Setup DMA configuration
101 * @dev: Device to apply DMA configuration
102 * @np: Pointer to OF node having DMA configuration
103 * @force_dma: Whether device is to be set up by of_dma_configure() even if
104 * DMA capability is not explicitly described by firmware.
105 * @id: Optional const pointer value input id
106 *
107 * Try to get devices's DMA configuration from DT and update it
108 * accordingly.
109 *
110 * If platform code needs to use its own special DMA configuration, it
111 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
112 * to fix up DMA configuration.
113 */
114int of_dma_configure_id(struct device *dev, struct device_node *np,
115 bool force_dma, const u32 *id)
116{
117 const struct iommu_ops *iommu;
118 const struct bus_dma_region *map = NULL;
119 struct device_node *bus_np;
120 u64 dma_start = 0;
121 u64 mask, end, size = 0;
122 bool coherent;
123 int ret;
124
125 if (np == dev->of_node)
126 bus_np = __of_get_dma_parent(np);
127 else
128 bus_np = of_node_get(np);
129
130 ret = of_dma_get_range(bus_np, &map);
131 of_node_put(bus_np);
132 if (ret < 0) {
133 /*
134 * For legacy reasons, we have to assume some devices need
135 * DMA configuration regardless of whether "dma-ranges" is
136 * correctly specified or not.
137 */
138 if (!force_dma)
139 return ret == -ENODEV ? 0 : ret;
140 } else {
141 const struct bus_dma_region *r = map;
142 u64 dma_end = 0;
143
144 /* Determine the overall bounds of all DMA regions */
145 for (dma_start = ~0; r->size; r++) {
146 /* Take lower and upper limits */
147 if (r->dma_start < dma_start)
148 dma_start = r->dma_start;
149 if (r->dma_start + r->size > dma_end)
150 dma_end = r->dma_start + r->size;
151 }
152 size = dma_end - dma_start;
153
154 /*
155 * Add a work around to treat the size as mask + 1 in case
156 * it is defined in DT as a mask.
157 */
158 if (size & 1) {
159 dev_warn(dev, "Invalid size 0x%llx for dma-range(s)\n",
160 size);
161 size = size + 1;
162 }
163
164 if (!size) {
165 dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
166 kfree(map);
167 return -EINVAL;
168 }
169 }
170
171 /*
172 * If @dev is expected to be DMA-capable then the bus code that created
173 * it should have initialised its dma_mask pointer by this point. For
174 * now, we'll continue the legacy behaviour of coercing it to the
175 * coherent mask if not, but we'll no longer do so quietly.
176 */
177 if (!dev->dma_mask) {
178 dev_warn(dev, "DMA mask not set\n");
179 dev->dma_mask = &dev->coherent_dma_mask;
180 }
181
182 if (!size && dev->coherent_dma_mask)
183 size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
184 else if (!size)
185 size = 1ULL << 32;
186
187 /*
188 * Limit coherent and dma mask based on size and default mask
189 * set by the driver.
190 */
191 end = dma_start + size - 1;
192 mask = DMA_BIT_MASK(ilog2(end) + 1);
193 dev->coherent_dma_mask &= mask;
194 *dev->dma_mask &= mask;
195 /* ...but only set bus limit and range map if we found valid dma-ranges earlier */
196 if (!ret) {
197 dev->bus_dma_limit = end;
198 dev->dma_range_map = map;
199 }
200
201 coherent = of_dma_is_coherent(np);
202 dev_dbg(dev, "device is%sdma coherent\n",
203 coherent ? " " : " not ");
204
205 iommu = of_iommu_configure(dev, np, id);
206 if (PTR_ERR(iommu) == -EPROBE_DEFER) {
207 /* Don't touch range map if it wasn't set from a valid dma-ranges */
208 if (!ret)
209 dev->dma_range_map = NULL;
210 kfree(map);
211 return -EPROBE_DEFER;
212 }
213
214 dev_dbg(dev, "device is%sbehind an iommu\n",
215 iommu ? " " : " not ");
216
217 arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
218
219 if (!iommu)
220 of_dma_set_restricted_buffer(dev, np);
221
222 return 0;
223}
224EXPORT_SYMBOL_GPL(of_dma_configure_id);
225
226int of_device_register(struct platform_device *pdev)
227{
228 device_initialize(&pdev->dev);
229 return of_device_add(pdev);
230}
231EXPORT_SYMBOL(of_device_register);
232
233void of_device_unregister(struct platform_device *ofdev)
234{
235 device_unregister(&ofdev->dev);
236}
237EXPORT_SYMBOL(of_device_unregister);
238
239const void *of_device_get_match_data(const struct device *dev)
240{
241 const struct of_device_id *match;
242
243 match = of_match_device(dev->driver->of_match_table, dev);
244 if (!match)
245 return NULL;
246
247 return match->data;
248}
249EXPORT_SYMBOL(of_device_get_match_data);
250
251static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
252{
253 const char *compat;
254 char *c;
255 struct property *p;
256 ssize_t csize;
257 ssize_t tsize;
258
259 if ((!dev) || (!dev->of_node))
260 return -ENODEV;
261
262 /* Name & Type */
263 /* %p eats all alphanum characters, so %c must be used here */
264 csize = snprintf(str, len, "of:N%pOFn%c%s", dev->of_node, 'T',
265 of_node_get_device_type(dev->of_node));
266 tsize = csize;
267 len -= csize;
268 if (str)
269 str += csize;
270
271 of_property_for_each_string(dev->of_node, "compatible", p, compat) {
272 csize = strlen(compat) + 1;
273 tsize += csize;
274 if (csize > len)
275 continue;
276
277 csize = snprintf(str, len, "C%s", compat);
278 for (c = str; c; ) {
279 c = strchr(c, ' ');
280 if (c)
281 *c++ = '_';
282 }
283 len -= csize;
284 str += csize;
285 }
286
287 return tsize;
288}
289
290int of_device_request_module(struct device *dev)
291{
292 char *str;
293 ssize_t size;
294 int ret;
295
296 size = of_device_get_modalias(dev, NULL, 0);
297 if (size < 0)
298 return size;
299
300 str = kmalloc(size + 1, GFP_KERNEL);
301 if (!str)
302 return -ENOMEM;
303
304 of_device_get_modalias(dev, str, size);
305 str[size] = '\0';
306 ret = request_module(str);
307 kfree(str);
308
309 return ret;
310}
311EXPORT_SYMBOL_GPL(of_device_request_module);
312
313/**
314 * of_device_modalias - Fill buffer with newline terminated modalias string
315 * @dev: Calling device
316 * @str: Modalias string
317 * @len: Size of @str
318 */
319ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
320{
321 ssize_t sl = of_device_get_modalias(dev, str, len - 2);
322 if (sl < 0)
323 return sl;
324 if (sl > len - 2)
325 return -ENOMEM;
326
327 str[sl++] = '\n';
328 str[sl] = 0;
329 return sl;
330}
331EXPORT_SYMBOL_GPL(of_device_modalias);
332
333/**
334 * of_device_uevent - Display OF related uevent information
335 * @dev: Device to display the uevent information for
336 * @env: Kernel object's userspace event reference to fill up
337 */
338void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
339{
340 const char *compat, *type;
341 struct alias_prop *app;
342 struct property *p;
343 int seen = 0;
344
345 if ((!dev) || (!dev->of_node))
346 return;
347
348 add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);
349 add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);
350 type = of_node_get_device_type(dev->of_node);
351 if (type)
352 add_uevent_var(env, "OF_TYPE=%s", type);
353
354 /* Since the compatible field can contain pretty much anything
355 * it's not really legal to split it out with commas. We split it
356 * up using a number of environment variables instead. */
357 of_property_for_each_string(dev->of_node, "compatible", p, compat) {
358 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
359 seen++;
360 }
361 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
362
363 seen = 0;
364 mutex_lock(&of_mutex);
365 list_for_each_entry(app, &aliases_lookup, link) {
366 if (dev->of_node == app->np) {
367 add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
368 app->alias);
369 seen++;
370 }
371 }
372 mutex_unlock(&of_mutex);
373}
374
375int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
376{
377 int sl;
378
379 if ((!dev) || (!dev->of_node))
380 return -ENODEV;
381
382 /* Devicetree modalias is tricky, we add it in 2 steps */
383 if (add_uevent_var(env, "MODALIAS="))
384 return -ENOMEM;
385
386 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
387 sizeof(env->buf) - env->buflen);
388 if (sl >= (sizeof(env->buf) - env->buflen))
389 return -ENOMEM;
390 env->buflen += sl;
391
392 return 0;
393}
394EXPORT_SYMBOL_GPL(of_device_uevent_modalias);