// SPDX-License-Identifier: GPL-2.0#include <linux/string.h>#include <linux/kernel.h>#include <linux/of.h>#include <linux/of_device.h>#include <linux/of_address.h>#include <linux/of_iommu.h>#include <linux/dma-direct.h> /* for bus_dma_region */#include <linux/dma-map-ops.h>#include <linux/init.h>#include <linux/module.h>#include <linux/mod_devicetable.h>#include <linux/slab.h>#include <linux/platform_device.h> #include <asm/errno.h>#include "of_private.h" /** * of_match_device - Tell if a struct device matches an of_device_id list * @matches: array of of device match structures to search in * @dev: the of device structure to match against * * Used by a driver to check whether an platform_device present in the * system is in its list of supported devices. */const struct of_device_id *of_match_device(const struct of_device_id *matches,					   const struct device *dev){	if ((!matches) || (!dev->of_node))		return NULL;	return of_match_node(matches, dev->of_node);}EXPORT_SYMBOL(of_match_device); int of_device_add(struct platform_device *ofdev){	BUG_ON(ofdev->dev.of_node == NULL); 	/* name and id have to be set so that the platform bus doesn't get	 * confused on matching */	ofdev->name = dev_name(&ofdev->dev);	ofdev->id = PLATFORM_DEVID_NONE; 	/*	 * If this device has not binding numa node in devicetree, that is	 * of_node_to_nid returns NUMA_NO_NODE. device_add will assume that this	 * device is on the same node as the parent.	 */	set_dev_node(&ofdev->dev, of_node_to_nid(ofdev->dev.of_node)); 	return device_add(&ofdev->dev);} /** * of_dma_configure_id - Setup DMA configuration * @dev:	Device to apply DMA configuration * @np:		Pointer to OF node having DMA configuration * @force_dma:  Whether device is to be set up by of_dma_configure() even if *		DMA capability is not explicitly described by firmware. * @id:		Optional const pointer value input id * * Try to get devices's DMA configuration from DT and update it * accordingly. * * If platform code needs to use its own special DMA configuration, it * can use a platform bus notifier and handle BUS_NOTIFY_ADD_DEVICE events * to fix up DMA configuration. */int of_dma_configure_id(struct device *dev, struct device_node *np,			bool force_dma, const u32 *id){	const struct iommu_ops *iommu;	const struct bus_dma_region *map = NULL;	u64 dma_start = 0;	u64 mask, end, size = 0;	bool coherent;	int ret; 	ret = of_dma_get_range(np, &map);	if (ret < 0) {		/*		 * For legacy reasons, we have to assume some devices need		 * DMA configuration regardless of whether "dma-ranges" is		 * correctly specified or not.		 */		if (!force_dma)			return ret == -ENODEV ? 0 : ret;	} else {		const struct bus_dma_region *r = map;		u64 dma_end = 0; 		/* Determine the overall bounds of all DMA regions */		for (dma_start = ~0; r->size; r++) {			/* Take lower and upper limits */			if (r->dma_start < dma_start)				dma_start = r->dma_start;			if (r->dma_start + r->size > dma_end)				dma_end = r->dma_start + r->size;		}		size = dma_end - dma_start; 		/*		 * Add a work around to treat the size as mask + 1 in case		 * it is defined in DT as a mask.		 */		if (size & 1) {			dev_warn(dev, "Invalid size 0x%llx for dma-range(s)\n",				 size);			size = size + 1;		} 		if (!size) {			dev_err(dev, "Adjusted size 0x%llx invalid\n", size);			kfree(map);			return -EINVAL;		}	} 	/*	 * If @dev is expected to be DMA-capable then the bus code that created	 * it should have initialised its dma_mask pointer by this point. For	 * now, we'll continue the legacy behaviour of coercing it to the	 * coherent mask if not, but we'll no longer do so quietly.	 */	if (!dev->dma_mask) {		dev_warn(dev, "DMA mask not set\n");		dev->dma_mask = &dev->coherent_dma_mask;	} 	if (!size && dev->coherent_dma_mask)		size = max(dev->coherent_dma_mask, dev->coherent_dma_mask + 1);	else if (!size)		size = 1ULL << 32; 	/*	 * Limit coherent and dma mask based on size and default mask	 * set by the driver.	 */	end = dma_start + size - 1;	mask = DMA_BIT_MASK(ilog2(end) + 1);	dev->coherent_dma_mask &= mask;	*dev->dma_mask &= mask;	/* ...but only set bus limit and range map if we found valid dma-ranges earlier */	if (!ret) {		dev->bus_dma_limit = end;		dev->dma_range_map = map;	} 	coherent = of_dma_is_coherent(np);	dev_dbg(dev, "device is%sdma coherent\n",		coherent ? " " : " not "); 	iommu = of_iommu_configure(dev, np, id);	if (PTR_ERR(iommu) == -EPROBE_DEFER) {		/* Don't touch range map if it wasn't set from a valid dma-ranges */		if (!ret)			dev->dma_range_map = NULL;		kfree(map);		return -EPROBE_DEFER;	} 	dev_dbg(dev, "device is%sbehind an iommu\n",		iommu ? " " : " not "); 	arch_setup_dma_ops(dev, dma_start, size, iommu, coherent); 	return 0;}EXPORT_SYMBOL_GPL(of_dma_configure_id); int of_device_register(struct platform_device *pdev){	device_initialize(&pdev->dev);	return of_device_add(pdev);}EXPORT_SYMBOL(of_device_register); void of_device_unregister(struct platform_device *ofdev){	device_unregister(&ofdev->dev);}EXPORT_SYMBOL(of_device_unregister); const void *of_device_get_match_data(const struct device *dev){	const struct of_device_id *match; 	match = of_match_device(dev->driver->of_match_table, dev);	if (!match)		return NULL; 	return match->data;}EXPORT_SYMBOL(of_device_get_match_data); static ssize_t of_device_get_modalias(struct device *dev, char *str, ssize_t len){	const char *compat;	char *c;	struct property *p;	ssize_t csize;	ssize_t tsize; 	if ((!dev) || (!dev->of_node))		return -ENODEV; 	/* Name & Type */	/* %p eats all alphanum characters, so %c must be used here */	csize = snprintf(str, len, "of:N%pOFn%c%s", dev->of_node, 'T',			 of_node_get_device_type(dev->of_node));	tsize = csize;	len -= csize;	if (str)		str += csize; 	of_property_for_each_string(dev->of_node, "compatible", p, compat) {		csize = strlen(compat) + 1;		tsize += csize;		if (csize > len)			continue; 		csize = snprintf(str, len, "C%s", compat);		for (c = str; c; ) {			c = strchr(c, ' ');			if (c)				*c++ = '_';		}		len -= csize;		str += csize;	} 	return tsize;} int of_device_request_module(struct device *dev){	char *str;	ssize_t size;	int ret; 	size = of_device_get_modalias(dev, NULL, 0);	if (size < 0)		return size; 	str = kmalloc(size + 1, GFP_KERNEL);	if (!str)		return -ENOMEM; 	of_device_get_modalias(dev, str, size);	str[size] = '\0';	ret = request_module(str);	kfree(str); 	return ret;}EXPORT_SYMBOL_GPL(of_device_request_module); /** * of_device_modalias - Fill buffer with newline terminated modalias string * @dev:	Calling device * @str:	Modalias string * @len:	Size of @str */ssize_t of_device_modalias(struct device *dev, char *str, ssize_t len){	ssize_t sl = of_device_get_modalias(dev, str, len - 2);	if (sl < 0)		return sl;	if (sl > len - 2)		return -ENOMEM; 	str[sl++] = '\n';	str[sl] = 0;	return sl;}EXPORT_SYMBOL_GPL(of_device_modalias); /** * of_device_uevent - Display OF related uevent information * @dev:	Device to apply DMA configuration * @env:	Kernel object's userspace event reference */void of_device_uevent(struct device *dev, struct kobj_uevent_env *env){	const char *compat, *type;	struct alias_prop *app;	struct property *p;	int seen = 0; 	if ((!dev) || (!dev->of_node))		return; 	add_uevent_var(env, "OF_NAME=%pOFn", dev->of_node);	add_uevent_var(env, "OF_FULLNAME=%pOF", dev->of_node);	type = of_node_get_device_type(dev->of_node);	if (type)		add_uevent_var(env, "OF_TYPE=%s", type); 	/* Since the compatible field can contain pretty much anything	 * it's not really legal to split it out with commas. We split it	 * up using a number of environment variables instead. */	of_property_for_each_string(dev->of_node, "compatible", p, compat) {		add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);		seen++;	}	add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen); 	seen = 0;	mutex_lock(&of_mutex);	list_for_each_entry(app, &aliases_lookup, link) {		if (dev->of_node == app->np) {			add_uevent_var(env, "OF_ALIAS_%d=%s", seen,				       app->alias);			seen++;		}	}	mutex_unlock(&of_mutex);} int of_device_uevent_modalias(struct device *dev, struct kobj_uevent_env *env){	int sl; 	if ((!dev) || (!dev->of_node))		return -ENODEV; 	/* Devicetree modalias is tricky, we add it in 2 steps */	if (add_uevent_var(env, "MODALIAS="))		return -ENOMEM; 	sl = of_device_get_modalias(dev, &env->buf[env->buflen-1],				    sizeof(env->buf) - env->buflen);	if (sl >= (sizeof(env->buf) - env->buflen))		return -ENOMEM;	env->buflen += sl; 	return 0;}EXPORT_SYMBOL_GPL(of_device_uevent_modalias);