Linux Audio

Check our new training course

Loading...
v3.1
 
  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}
v5.4
  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 *
 82 * Try to get devices's DMA configuration from DT and update it
 83 * accordingly.
 84 *
 85 * If platform code needs to use its own special DMA configuration, it
 86 * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events
 87 * to fix up DMA configuration.
 88 */
 89int of_dma_configure(struct device *dev, struct device_node *np, bool force_dma)
 90{
 91	u64 dma_addr, paddr, size = 0;
 92	int ret;
 93	bool coherent;
 94	unsigned long offset;
 95	const struct iommu_ops *iommu;
 96	u64 mask;
 97
 98	ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
 99	if (ret < 0) {
100		/*
101		 * For legacy reasons, we have to assume some devices need
102		 * DMA configuration regardless of whether "dma-ranges" is
103		 * correctly specified or not.
104		 */
105		if (!force_dma)
106			return ret == -ENODEV ? 0 : ret;
107
108		dma_addr = offset = 0;
109	} else {
110		offset = PFN_DOWN(paddr - dma_addr);
111
112		/*
113		 * Add a work around to treat the size as mask + 1 in case
114		 * it is defined in DT as a mask.
115		 */
116		if (size & 1) {
117			dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
118				 size);
119			size = size + 1;
120		}
121
122		if (!size) {
123			dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
124			return -EINVAL;
125		}
126		dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
127	}
128
129	/*
130	 * If @dev is expected to be DMA-capable then the bus code that created
131	 * it should have initialised its dma_mask pointer by this point. For
132	 * now, we'll continue the legacy behaviour of coercing it to the
133	 * coherent mask if not, but we'll no longer do so quietly.
134	 */
135	if (!dev->dma_mask) {
136		dev_warn(dev, "DMA mask not set\n");
137		dev->dma_mask = &dev->coherent_dma_mask;
138	}
139
140	if (!size && dev->coherent_dma_mask)
141		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);
142	else if (!size)
143		size = 1ULL << 32;
144
145	dev->dma_pfn_offset = offset;
146
147	/*
148	 * Limit coherent and dma mask based on size and default mask
149	 * set by the driver.
150	 */
151	mask = DMA_BIT_MASK(ilog2(dma_addr + size - 1) + 1);
152	dev->coherent_dma_mask &= mask;
153	*dev->dma_mask &= mask;
154	/* ...but only set bus mask if we found valid dma-ranges earlier */
155	if (!ret)
156		dev->bus_dma_mask = mask;
157
158	coherent = of_dma_is_coherent(np);
159	dev_dbg(dev, "device is%sdma coherent\n",
160		coherent ? " " : " not ");
161
162	iommu = of_iommu_configure(dev, np);
163	if (IS_ERR(iommu) && PTR_ERR(iommu) == -EPROBE_DEFER)
164		return -EPROBE_DEFER;
165
166	dev_dbg(dev, "device is%sbehind an iommu\n",
167		iommu ? " " : " not ");
168
169	arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
170
171	return 0;
172}
173EXPORT_SYMBOL_GPL(of_dma_configure);
174
175int of_device_register(struct platform_device *pdev)
176{
177	device_initialize(&pdev->dev);
178	return of_device_add(pdev);
179}
180EXPORT_SYMBOL(of_device_register);
181
182void of_device_unregister(struct platform_device *ofdev)
183{
184	device_unregister(&ofdev->dev);
185}
186EXPORT_SYMBOL(of_device_unregister);
187
188const void *of_device_get_match_data(const struct device *dev)
189{
190	const struct of_device_id *match;
 
 
191
192	match = of_match_device(dev->driver->of_match_table, dev);
193	if (!match)
194		return NULL;
195
196	return match->data;
197}
198EXPORT_SYMBOL(of_device_get_match_data);
199
200static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len)
201{
202	const char *compat;
203	char *c;
204	struct property *p;
205	ssize_t csize;
206	ssize_t tsize;
 
 
 
 
 
 
 
 
 
 
 
 
207
208	if ((!dev) || (!dev->of_node))
209		return -ENODEV;
210
211	/* Name & Type */
212	/* %p eats all alphanum characters, so %c must be used here */
213	csize = snprintf(str, len, "of:N%pOFn%c%s", dev->of_node, 'T',
214			 of_node_get_device_type(dev->of_node));
215	tsize = csize;
216	len -= csize;
217	if (str)
218		str += csize;
219
220	of_property_for_each_string(dev->of_node, "compatible", p, compat) {
221		csize = strlen(compat) + 1;
222		tsize += csize;
223		if (csize > len)
224			continue;
225
226		csize = snprintf(str, len, "C%s", compat);
227		for (c = str; c; ) {
228			c = strchr(c, ' ');
229			if (c)
230				*c++ = '_';
231		}
232		len -= csize;
233		str += csize;
234	}
235
236	return tsize;
237}
238
239int of_device_request_module(struct device *dev)
240{
241	char *str;
242	ssize_t size;
243	int ret;
244
245	size = of_device_get_modalias(dev, NULL, 0);
246	if (size < 0)
247		return size;
248
249	str = kmalloc(size + 1, GFP_KERNEL);
250	if (!str)
251		return -ENOMEM;
252
253	of_device_get_modalias(dev, str, size);
254	str[size] = '\0';
255	ret = request_module(str);
256	kfree(str);
257
258	return ret;
259}
260EXPORT_SYMBOL_GPL(of_device_request_module);
261
262/**
263 * of_device_modalias - Fill buffer with newline terminated modalias string
264 */
265ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len)
266{
267	ssize_t sl = of_device_get_modalias(dev, str, len - 2);
268	if (sl < 0)
269		return sl;
270	if (sl > len - 2)
271		return -ENOMEM;
272
273	str[sl++] = '\n';
274	str[sl] = 0;
275	return sl;
276}
277EXPORT_SYMBOL_GPL(of_device_modalias);
278
279/**
280 * of_device_uevent - Display OF related uevent information
281 */
282void of_device_uevent(struct device *dev, struct kobj_uevent_env *env)
283{
284	const char *compat, *type;
285	struct alias_prop *app;
286	struct property *p;
287	int seen = 0;
288
289	if ((!dev) || (!dev->of_node))
290		return;
 
 
 
291
292	add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);
293	add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);
294	type = of_node_get_device_type(dev->of_node);
295	if (type)
296		add_uevent_var(env, "OF_TYPE=%s", type);
297
298	/* Since the compatible field can contain pretty much anything
299	 * it's not really legal to split it out with commas. We split it
300	 * up using a number of environment variables instead. */
301	of_property_for_each_string(dev->of_node, "compatible", p, compat) {
302		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
 
 
 
 
 
 
 
303		seen++;
304	}
305	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
306
307	seen = 0;
308	mutex_lock(&of_mutex);
309	list_for_each_entry(app, &aliases_lookup, link) {
310		if (dev->of_node == app->np) {
311			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,
312				       app->alias);
313			seen++;
314		}
315	}
316	mutex_unlock(&of_mutex);
317}
318
319int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env)
320{
321	int sl;
322
323	if ((!dev) || (!dev->of_node))
324		return -ENODEV;
325
326	/* Devicetree modalias is tricky, we add it in 2 steps */
327	if (add_uevent_var(env, "MODALIAS="))
328		return -ENOMEM;
329
330	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],
331				    sizeof(env->buf) - env->buflen);
332	if (sl >= (sizeof(env->buf) - env->buflen))
333		return -ENOMEM;
334	env->buflen += sl;
335
336	return 0;
337}
338EXPORT_SYMBOL_GPL(of_device_uevent_modalias);