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v5.9
  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/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>
 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))
 30		return NULL;
 31	return of_match_node(matches, dev->of_node);
 32}
 33EXPORT_SYMBOL(of_match_device);
 34
 35struct platform_device *of_dev_get(struct platform_device *dev)
 36{
 37	struct device *tmp;
 38
 39	if (!dev)
 40		return NULL;
 41	tmp = get_device(&dev->dev);
 42	if (tmp)
 43		return to_platform_device(tmp);
 44	else
 45		return NULL;
 46}
 47EXPORT_SYMBOL(of_dev_get);
 48
 49void of_dev_put(struct platform_device *dev)
 50{
 51	if (dev)
 52		put_device(&dev->dev);
 53}
 54EXPORT_SYMBOL(of_dev_put);
 55
 56int of_device_add(struct platform_device *ofdev)
 57{
 58	BUG_ON(ofdev->dev.of_node == NULL);
 59
 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;
 64
 65	/*
 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.
 69	 */
 70	set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node));
 71
 72	return device_add(&ofdev->dev);
 73}
 74
 75/**
 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
 82 *
 83 * Try to get devices's DMA configuration from DT and update it
 84 * accordingly.
 85 *
 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.
 89 */
 90int of_dma_configure_id(struct device *dev, struct device_node *np,
 91			bool force_dma, const u32 *id)
 92{
 93	u64 dma_addr, paddr, size = 0;
 94	int ret;
 95	bool coherent;
 96	unsigned long offset;
 97	const struct iommu_ops *iommu;
 98	u64 mask, end;
 
 
 
 
 
 
 
 
 
 
 
 
 
 99
100	ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
101	if (ret < 0) {
102		/*
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.
106		 */
107		if (!force_dma)
108			return ret == -ENODEV ? 0 : ret;
109
110		dma_addr = offset = 0;
 
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 -EINVAL;
127		}
128		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
129	}
130
131	/*
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.
136	 */
137	if (!dev->dma_mask) {
138		dev_warn(dev, "DMA mask not set\n");
139		dev->dma_mask = &dev->coherent_dma_mask;
140	}
141
142	if (!size && dev->coherent_dma_mask)
143		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
144	else if (!size)
145		size = 1ULL << 32;
146
147	dev->dma_pfn_offset = offset;
148
149	/*
150	 * Limit coherent and dma mask based on size and default mask
151	 * set by the driver.
152	 */
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 */
158	if (!ret)
159		dev->bus_dma_limit = end;
160
161	coherent = of_dma_is_coherent(np);
162	dev_dbg(dev, "device is%sdma coherent\n",
163		coherent ? " " : " not ");
164
165	iommu = of_iommu_configure(dev, np, id);
166	if (PTR_ERR(iommu) == -EPROBE_DEFER)
167		return -EPROBE_DEFER;
168
169	dev_dbg(dev, "device is%sbehind an iommu\n",
170		iommu ? " " : " not ");
171
172	arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
173
174	return 0;
175}
176EXPORT_SYMBOL_GPL(of_dma_configure_id);
177
178int of_device_register(struct platform_device *pdev)
179{
180	device_initialize(&pdev->dev);
181	return of_device_add(pdev);
182}
183EXPORT_SYMBOL(of_device_register);
184
185void of_device_unregister(struct platform_device *ofdev)
186{
187	device_unregister(&ofdev->dev);
188}
189EXPORT_SYMBOL(of_device_unregister);
190
191const void *of_device_get_match_data(const struct device *dev)
192{
193	const struct of_device_id *match;
194
195	match = of_match_device(dev->driver->of_match_table, dev);
196	if (!match)
197		return NULL;
198
199	return match->data;
200}
201EXPORT_SYMBOL(of_device_get_match_data);
202
203static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
204{
205	const char *compat;
206	char *c;
207	struct property *p;
208	ssize_t csize;
209	ssize_t tsize;
210
211	if ((!dev) || (!dev->of_node))
212		return -ENODEV;
213
214	/* Name & Type */
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));
218	tsize = csize;
219	len -= csize;
220	if (str)
221		str += csize;
222
223	of_property_for_each_string(dev->of_node, "compatible", p, compat) {
224		csize = strlen(compat) + 1;
225		tsize += csize;
226		if (csize > len)
227			continue;
228
229		csize = snprintf(str, len, "C%s", compat);
230		for (c = str; c; ) {
231			c = strchr(c, ' ');
232			if (c)
233				*c++ = '_';
234		}
235		len -= csize;
236		str += csize;
237	}
238
239	return tsize;
240}
241
242int of_device_request_module(struct device *dev)
243{
244	char *str;
245	ssize_t size;
246	int ret;
247
248	size = of_device_get_modalias(dev, NULL, 0);
249	if (size < 0)
250		return size;
251
252	str = kmalloc(size + 1, GFP_KERNEL);
253	if (!str)
254		return -ENOMEM;
255
256	of_device_get_modalias(dev, str, size);
257	str[size] = '\0';
258	ret = request_module(str);
259	kfree(str);
260
261	return ret;
262}
263EXPORT_SYMBOL_GPL(of_device_request_module);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
264
265/**
266 * of_device_modalias - Fill buffer with newline terminated modalias string
267 */
268ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
269{
270	ssize_t sl = of_device_get_modalias(dev, str, len - 2);
271	if (sl < 0)
272		return sl;
273	if (sl > len - 2)
274		return -ENOMEM;
275
276	str[sl++] = '\n';
277	str[sl] = 0;
278	return sl;
279}
280EXPORT_SYMBOL_GPL(of_device_modalias);
281
282/**
283 * of_device_uevent - Display OF related uevent information
284 */
285void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
286{
287	const char *compat, *type;
288	struct alias_prop *app;
289	struct property *p;
290	int seen = 0;
291
292	if ((!dev) || (!dev->of_node))
293		return;
294
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);
298	if (type)
299		add_uevent_var(env, "OF_TYPE=%s", type);
300
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);
 
 
 
306		seen++;
307	}
308	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
309
310	seen = 0;
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,
315				       app->alias);
316			seen++;
317		}
318	}
319	mutex_unlock(&of_mutex);
320}
321
322int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
323{
324	int sl;
325
326	if ((!dev) || (!dev->of_node))
327		return -ENODEV;
328
329	/* Devicetree modalias is tricky, we add it in 2 steps */
330	if (add_uevent_var(env, "MODALIAS="))
331		return -ENOMEM;
332
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))
336		return -ENOMEM;
337	env->buflen += sl;
338
339	return 0;
340}
341EXPORT_SYMBOL_GPL(of_device_uevent_modalias);
v4.6
 
  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 */
 24const 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}
 31EXPORT_SYMBOL(of_match_device);
 32
 33struct 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}
 45EXPORT_SYMBOL(of_dev_get);
 46
 47void of_dev_put(struct platform_device *dev)
 48{
 49	if (dev)
 50		put_device(&dev->dev);
 51}
 52EXPORT_SYMBOL(of_dev_put);
 53
 54int 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 */
 85void 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	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}
152EXPORT_SYMBOL_GPL(of_dma_configure);
153
154int of_device_register(struct platform_device *pdev)
155{
156	device_initialize(&pdev->dev);
157	return of_device_add(pdev);
158}
159EXPORT_SYMBOL(of_device_register);
160
161void of_device_unregister(struct platform_device *ofdev)
162{
163	device_unregister(&ofdev->dev);
164}
165EXPORT_SYMBOL(of_device_unregister);
166
167const 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}
177EXPORT_SYMBOL(of_device_get_match_data);
178
179ssize_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 tsize;
 
 
227}
 
228
229/**
230 * of_device_uevent - Display OF related uevent information
231 */
232void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
233{
234	const char *compat;
235	struct alias_prop *app;
236	int seen = 0, cplen, sl;
 
237
238	if ((!dev) || (!dev->of_node))
239		return;
240
241	add_uevent_var(env, "OF_NAME=%s", dev->of_node->name);
242	add_uevent_var(env, "OF_FULLNAME=%s", dev->of_node->full_name);
243	if (dev->of_node->type && strcmp("<NULL>", dev->of_node->type) != 0)
244		add_uevent_var(env, "OF_TYPE=%s", dev->of_node->type);
 
245
246	/* Since the compatible field can contain pretty much anything
247	 * it's not really legal to split it out with commas. We split it
248	 * up using a number of environment variables instead. */
249	compat = of_get_property(dev->of_node, "compatible", &cplen);
250	while (compat && *compat && cplen > 0) {
251		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
252		sl = strlen(compat) + 1;
253		compat += sl;
254		cplen -= sl;
255		seen++;
256	}
257	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
258
259	seen = 0;
260	mutex_lock(&of_mutex);
261	list_for_each_entry(app, &aliases_lookup, link) {
262		if (dev->of_node == app->np) {
263			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
264				       app->alias);
265			seen++;
266		}
267	}
268	mutex_unlock(&of_mutex);
269}
270
271int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
272{
273	int sl;
274
275	if ((!dev) || (!dev->of_node))
276		return -ENODEV;
277
278	/* Devicetree modalias is tricky, we add it in 2 steps */
279	if (add_uevent_var(env, "MODALIAS="))
280		return -ENOMEM;
281
282	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
283				    sizeof(env->buf) - env->buflen);
284	if (sl >= (sizeof(env->buf) - env->buflen))
285		return -ENOMEM;
286	env->buflen += sl;
287
288	return 0;
289}