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1// SPDX-License-Identifier: GPL-2.0
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/of_reserved_mem.h>
8#include <linux/dma-direct.h> /* for bus_dma_region */
9#include <linux/dma-map-ops.h>
10#include <linux/init.h>
11#include <linux/mod_devicetable.h>
12#include <linux/slab.h>
13#include <linux/platform_device.h>
14
15#include <asm/errno.h>
16#include "of_private.h"
17
18/**
19 * of_match_device - Tell if a struct device matches an of_device_id list
20 * @matches: array of of device match structures to search in
21 * @dev: the of device structure to match against
22 *
23 * Used by a driver to check whether an platform_device present in the
24 * system is in its list of supported devices.
25 */
26const struct of_device_id *of_match_device(const struct of_device_id *matches,
27 const struct device *dev)
28{
29 if (!matches || !dev->of_node || dev->of_node_reused)
30 return NULL;
31 return of_match_node(matches, dev->of_node);
32}
33EXPORT_SYMBOL(of_match_device);
34
35static void
36of_dma_set_restricted_buffer(struct device *dev, struct device_node *np)
37{
38 struct device_node *node, *of_node = dev->of_node;
39 int count, i;
40
41 if (!IS_ENABLED(CONFIG_DMA_RESTRICTED_POOL))
42 return;
43
44 count = of_property_count_elems_of_size(of_node, "memory-region",
45 sizeof(u32));
46 /*
47 * If dev->of_node doesn't exist or doesn't contain memory-region, try
48 * the OF node having DMA configuration.
49 */
50 if (count <= 0) {
51 of_node = np;
52 count = of_property_count_elems_of_size(
53 of_node, "memory-region", sizeof(u32));
54 }
55
56 for (i = 0; i < count; i++) {
57 node = of_parse_phandle(of_node, "memory-region", i);
58 /*
59 * There might be multiple memory regions, but only one
60 * restricted-dma-pool region is allowed.
61 */
62 if (of_device_is_compatible(node, "restricted-dma-pool") &&
63 of_device_is_available(node)) {
64 of_node_put(node);
65 break;
66 }
67 of_node_put(node);
68 }
69
70 /*
71 * Attempt to initialize a restricted-dma-pool region if one was found.
72 * Note that count can hold a negative error code.
73 */
74 if (i < count && of_reserved_mem_device_init_by_idx(dev, of_node, i))
75 dev_warn(dev, "failed to initialise \"restricted-dma-pool\" memory node\n");
76}
77
78/**
79 * of_dma_configure_id - Setup DMA configuration
80 * @dev: Device to apply DMA configuration
81 * @np: Pointer to OF node having DMA configuration
82 * @force_dma: Whether device is to be set up by of_dma_configure() even if
83 * DMA capability is not explicitly described by firmware.
84 * @id: Optional const pointer value input id
85 *
86 * Try to get devices's DMA configuration from DT and update it
87 * accordingly.
88 *
89 * If platform code needs to use its own special DMA configuration, it
90 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
91 * to fix up DMA configuration.
92 */
93int of_dma_configure_id(struct device *dev, struct device_node *np,
94 bool force_dma, const u32 *id)
95{
96 const struct bus_dma_region *map = NULL;
97 struct device_node *bus_np;
98 u64 mask, end = 0;
99 bool coherent, set_map = false;
100 int ret;
101
102 if (np == dev->of_node)
103 bus_np = __of_get_dma_parent(np);
104 else
105 bus_np = of_node_get(np);
106
107 ret = of_dma_get_range(bus_np, &map);
108 of_node_put(bus_np);
109 if (ret < 0) {
110 /*
111 * For legacy reasons, we have to assume some devices need
112 * DMA configuration regardless of whether "dma-ranges" is
113 * correctly specified or not.
114 */
115 if (!force_dma)
116 return ret == -ENODEV ? 0 : ret;
117 } else {
118 /* Determine the overall bounds of all DMA regions */
119 end = dma_range_map_max(map);
120 set_map = true;
121 }
122
123 /*
124 * If @dev is expected to be DMA-capable then the bus code that created
125 * it should have initialised its dma_mask pointer by this point. For
126 * now, we'll continue the legacy behaviour of coercing it to the
127 * coherent mask if not, but we'll no longer do so quietly.
128 */
129 if (!dev->dma_mask) {
130 dev_warn(dev, "DMA mask not set\n");
131 dev->dma_mask = &dev->coherent_dma_mask;
132 }
133
134 if (!end && dev->coherent_dma_mask)
135 end = dev->coherent_dma_mask;
136 else if (!end)
137 end = (1ULL << 32) - 1;
138
139 /*
140 * Limit coherent and dma mask based on size and default mask
141 * set by the driver.
142 */
143 mask = DMA_BIT_MASK(ilog2(end) + 1);
144 dev->coherent_dma_mask &= mask;
145 *dev->dma_mask &= mask;
146 /* ...but only set bus limit and range map if we found valid dma-ranges earlier */
147 if (set_map) {
148 dev->bus_dma_limit = end;
149 dev->dma_range_map = map;
150 }
151
152 coherent = of_dma_is_coherent(np);
153 dev_dbg(dev, "device is%sdma coherent\n",
154 coherent ? " " : " not ");
155
156 ret = of_iommu_configure(dev, np, id);
157 if (ret == -EPROBE_DEFER) {
158 /* Don't touch range map if it wasn't set from a valid dma-ranges */
159 if (set_map)
160 dev->dma_range_map = NULL;
161 kfree(map);
162 return -EPROBE_DEFER;
163 }
164 /* Take all other IOMMU errors to mean we'll just carry on without it */
165 dev_dbg(dev, "device is%sbehind an iommu\n",
166 !ret ? " " : " not ");
167
168 arch_setup_dma_ops(dev, coherent);
169
170 if (ret)
171 of_dma_set_restricted_buffer(dev, np);
172
173 return 0;
174}
175EXPORT_SYMBOL_GPL(of_dma_configure_id);
176
177const void *of_device_get_match_data(const struct device *dev)
178{
179 const struct of_device_id *match;
180
181 match = of_match_device(dev->driver->of_match_table, dev);
182 if (!match)
183 return NULL;
184
185 return match->data;
186}
187EXPORT_SYMBOL(of_device_get_match_data);
188
189/**
190 * of_device_modalias - Fill buffer with newline terminated modalias string
191 * @dev: Calling device
192 * @str: Modalias string
193 * @len: Size of @str
194 */
195ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
196{
197 ssize_t sl;
198
199 if (!dev || !dev->of_node || dev->of_node_reused)
200 return -ENODEV;
201
202 sl = of_modalias(dev->of_node, str, len - 2);
203 if (sl < 0)
204 return sl;
205 if (sl > len - 2)
206 return -ENOMEM;
207
208 str[sl++] = '\n';
209 str[sl] = 0;
210 return sl;
211}
212EXPORT_SYMBOL_GPL(of_device_modalias);
213
214/**
215 * of_device_uevent - Display OF related uevent information
216 * @dev: Device to display the uevent information for
217 * @env: Kernel object's userspace event reference to fill up
218 */
219void of_device_uevent(const struct device *dev, struct kobj_uevent_env *env)
220{
221 const char *compat, *type;
222 struct alias_prop *app;
223 struct property *p;
224 int seen = 0;
225
226 if ((!dev) || (!dev->of_node))
227 return;
228
229 add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);
230 add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);
231 type = of_node_get_device_type(dev->of_node);
232 if (type)
233 add_uevent_var(env, "OF_TYPE=%s", type);
234
235 /* Since the compatible field can contain pretty much anything
236 * it's not really legal to split it out with commas. We split it
237 * up using a number of environment variables instead. */
238 of_property_for_each_string(dev->of_node, "compatible", p, compat) {
239 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
240 seen++;
241 }
242 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
243
244 seen = 0;
245 mutex_lock(&of_mutex);
246 list_for_each_entry(app, &aliases_lookup, link) {
247 if (dev->of_node == app->np) {
248 add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
249 app->alias);
250 seen++;
251 }
252 }
253 mutex_unlock(&of_mutex);
254}
255EXPORT_SYMBOL_GPL(of_device_uevent);
256
257int of_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env)
258{
259 int sl;
260
261 if ((!dev) || (!dev->of_node) || dev->of_node_reused)
262 return -ENODEV;
263
264 /* Devicetree modalias is tricky, we add it in 2 steps */
265 if (add_uevent_var(env, "MODALIAS="))
266 return -ENOMEM;
267
268 sl = of_modalias(dev->of_node, &env->buf[env->buflen-1],
269 sizeof(env->buf) - env->buflen);
270 if (sl < 0)
271 return sl;
272 if (sl >= (sizeof(env->buf) - env->buflen))
273 return -ENOMEM;
274 env->buflen += sl;
275
276 return 0;
277}
278EXPORT_SYMBOL_GPL(of_device_uevent_modalias);
279
280/**
281 * of_device_make_bus_id - Use the device node data to assign a unique name
282 * @dev: pointer to device structure that is linked to a device tree node
283 *
284 * This routine will first try using the translated bus address to
285 * derive a unique name. If it cannot, then it will prepend names from
286 * parent nodes until a unique name can be derived.
287 */
288void of_device_make_bus_id(struct device *dev)
289{
290 struct device_node *node = dev->of_node;
291 const __be32 *reg;
292 u64 addr;
293 u32 mask;
294
295 /* Construct the name, using parent nodes if necessary to ensure uniqueness */
296 while (node->parent) {
297 /*
298 * If the address can be translated, then that is as much
299 * uniqueness as we need. Make it the first component and return
300 */
301 reg = of_get_property(node, "reg", NULL);
302 if (reg && (addr = of_translate_address(node, reg)) != OF_BAD_ADDR) {
303 if (!of_property_read_u32(node, "mask", &mask))
304 dev_set_name(dev, dev_name(dev) ? "%llx.%x.%pOFn:%s" : "%llx.%x.%pOFn",
305 addr, ffs(mask) - 1, node, dev_name(dev));
306
307 else
308 dev_set_name(dev, dev_name(dev) ? "%llx.%pOFn:%s" : "%llx.%pOFn",
309 addr, node, dev_name(dev));
310 return;
311 }
312
313 /* format arguments only used if dev_name() resolves to NULL */
314 dev_set_name(dev, dev_name(dev) ? "%s:%s" : "%s",
315 kbasename(node->full_name), dev_name(dev));
316 node = node->parent;
317 }
318}
319EXPORT_SYMBOL_GPL(of_device_make_bus_id);
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}