1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/string.h>
3 #include <linux/kernel.h>
5 #include <linux/of_device.h>
6 #include <linux/of_address.h>
7 #include <linux/of_iommu.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/mod_devicetable.h>
12 #include <linux/slab.h>
13 #include <linux/platform_device.h>
15 #include <asm/errno.h>
16 #include "of_private.h"
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
23 * Used by a driver to check whether an platform_device present in the
24 * system is in its list of supported devices.
26 const struct of_device_id *of_match_device(const struct of_device_id *matches,
27 const struct device *dev)
29 if ((!matches) || (!dev->of_node))
31 return of_match_node(matches, dev->of_node);
33 EXPORT_SYMBOL(of_match_device);
35 struct platform_device *of_dev_get(struct platform_device *dev)
41 tmp = get_device(&dev->dev);
43 return to_platform_device(tmp);
47 EXPORT_SYMBOL(of_dev_get);
49 void of_dev_put(struct platform_device *dev)
52 put_device(&dev->dev);
54 EXPORT_SYMBOL(of_dev_put);
56 int of_device_add(struct platform_device *ofdev)
58 BUG_ON(ofdev->dev.of_node == NULL);
60 /* name and id have to be set so that the platform bus doesn't get
61 * confused on matching */
62 ofdev->name = dev_name(&ofdev->dev);
63 ofdev->id = PLATFORM_DEVID_NONE;
66 * If this device has not binding numa node in devicetree, that is
67 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this
68 * device is on the same node as the parent.
70 set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
72 return device_add(&ofdev->dev);
76 * of_dma_configure - Setup DMA configuration
77 * @dev: Device to apply DMA configuration
78 * @np: Pointer to OF node having DMA configuration
79 * @force_dma: Whether device is to be set up by of_dma_configure() even if
80 * DMA capability is not explicitly described by firmware.
81 * @id: Optional const pointer value input id
83 * Try to get devices's DMA configuration from DT and update it
86 * If platform code needs to use its own special DMA configuration, it
87 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
88 * to fix up DMA configuration.
90 int of_dma_configure_id(struct device *dev, struct device_node *np,
91 bool force_dma, const u32 *id)
93 u64 dma_addr, paddr, size = 0;
97 const struct iommu_ops *iommu;
100 ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
103 * For legacy reasons, we have to assume some devices need
104 * DMA configuration regardless of whether "dma-ranges" is
105 * correctly specified or not.
108 return ret == -ENODEV ? 0 : ret;
110 dma_addr = offset = 0;
112 offset = PFN_DOWN(paddr - dma_addr);
115 * Add a work around to treat the size as mask + 1 in case
116 * it is defined in DT as a mask.
119 dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
125 dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
128 dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
132 * If @dev is expected to be DMA-capable then the bus code that created
133 * it should have initialised its dma_mask pointer by this point. For
134 * now, we'll continue the legacy behaviour of coercing it to the
135 * coherent mask if not, but we'll no longer do so quietly.
137 if (!dev->dma_mask) {
138 dev_warn(dev, "DMA mask not set\n");
139 dev->dma_mask = &dev->coherent_dma_mask;
142 if (!size && dev->coherent_dma_mask)
143 size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
147 dev->dma_pfn_offset = offset;
150 * Limit coherent and dma mask based on size and default mask
153 end = dma_addr + size - 1;
154 mask = DMA_BIT_MASK(ilog2(end) + 1);
155 dev->coherent_dma_mask &= mask;
156 *dev->dma_mask &= mask;
157 /* ...but only set bus limit if we found valid dma-ranges earlier */
159 dev->bus_dma_limit = end;
161 coherent = of_dma_is_coherent(np);
162 dev_dbg(dev, "device is%sdma coherent\n",
163 coherent ? " " : " not ");
165 iommu = of_iommu_configure(dev, np, id);
166 if (PTR_ERR(iommu) == -EPROBE_DEFER)
167 return -EPROBE_DEFER;
169 dev_dbg(dev, "device is%sbehind an iommu\n",
170 iommu ? " " : " not ");
172 arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
176 EXPORT_SYMBOL_GPL(of_dma_configure_id);
178 int of_device_register(struct platform_device *pdev)
180 device_initialize(&pdev->dev);
181 return of_device_add(pdev);
183 EXPORT_SYMBOL(of_device_register);
185 void of_device_unregister(struct platform_device *ofdev)
187 device_unregister(&ofdev->dev);
189 EXPORT_SYMBOL(of_device_unregister);
191 const void *of_device_get_match_data(const struct device *dev)
193 const struct of_device_id *match;
195 match = of_match_device(dev->driver->of_match_table, dev);
201 EXPORT_SYMBOL(of_device_get_match_data);
203 static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
211 if ((!dev) || (!dev->of_node))
215 /* %p eats all alphanum characters, so %c must be used here */
216 csize = snprintf(str, len, "of:N%pOFn%c%s", dev->of_node, 'T',
217 of_node_get_device_type(dev->of_node));
223 of_property_for_each_string(dev->of_node, "compatible", p, compat) {
224 csize = strlen(compat) + 1;
229 csize = snprintf(str, len, "C%s", compat);
242 int of_device_request_module(struct device *dev)
248 size = of_device_get_modalias(dev, NULL, 0);
252 str = kmalloc(size + 1, GFP_KERNEL);
256 of_device_get_modalias(dev, str, size);
258 ret = request_module(str);
263 EXPORT_SYMBOL_GPL(of_device_request_module);
266 * of_device_modalias - Fill buffer with newline terminated modalias string
268 ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
270 ssize_t sl = of_device_get_modalias(dev, str, len - 2);
280 EXPORT_SYMBOL_GPL(of_device_modalias);
283 * of_device_uevent - Display OF related uevent information
285 void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
287 const char *compat, *type;
288 struct alias_prop *app;
292 if ((!dev) || (!dev->of_node))
295 add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);
296 add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);
297 type = of_node_get_device_type(dev->of_node);
299 add_uevent_var(env, "OF_TYPE=%s", type);
301 /* Since the compatible field can contain pretty much anything
302 * it's not really legal to split it out with commas. We split it
303 * up using a number of environment variables instead. */
304 of_property_for_each_string(dev->of_node, "compatible", p, compat) {
305 add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
308 add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
311 mutex_lock(&of_mutex);
312 list_for_each_entry(app, &aliases_lookup, link) {
313 if (dev->of_node == app->np) {
314 add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
319 mutex_unlock(&of_mutex);
322 int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
326 if ((!dev) || (!dev->of_node))
329 /* Devicetree modalias is tricky, we add it in 2 steps */
330 if (add_uevent_var(env, "MODALIAS="))
333 sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
334 sizeof(env->buf) - env->buflen);
335 if (sl >= (sizeof(env->buf) - env->buflen))
341 EXPORT_SYMBOL_GPL(of_device_uevent_modalias);