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	Simplify devm_ioport_unmap() implementation by dedicated API devres_release(), compared with current solution, namely ioport_unmap() + devres_destroy(), devres_release() has below advantages: - it is simpler if devm_ioport_unmap()'s parameter @addr was ever returned by devm_ioport_map(). - it can avoid unnecessary ioport_unmap(@addr) if @addr was not ever returned by devm_ioport_map(). Signed-off-by: Zijun Hu <quic_zijuhu@quicinc.com> Link: https://lore.kernel.org/r/20240918-fix_lib_devres-v1-2-e696ab5486e6@quicinc.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
		
			
				
	
	
		
			398 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			398 lines
		
	
	
	
		
			10 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0
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#include <linux/bug.h>
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#include <linux/device.h>
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#include <linux/errno.h>
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#include <linux/export.h>
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#include <linux/gfp_types.h>
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#include <linux/io.h>
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#include <linux/ioport.h>
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#include <linux/of_address.h>
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#include <linux/types.h>
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enum devm_ioremap_type {
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	DEVM_IOREMAP = 0,
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	DEVM_IOREMAP_UC,
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	DEVM_IOREMAP_WC,
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	DEVM_IOREMAP_NP,
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};
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void devm_ioremap_release(struct device *dev, void *res)
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{
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	iounmap(*(void __iomem **)res);
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}
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static int devm_ioremap_match(struct device *dev, void *res, void *match_data)
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{
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	return *(void **)res == match_data;
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}
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static void __iomem *__devm_ioremap(struct device *dev, resource_size_t offset,
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				    resource_size_t size,
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				    enum devm_ioremap_type type)
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{
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	void __iomem **ptr, *addr = NULL;
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	ptr = devres_alloc_node(devm_ioremap_release, sizeof(*ptr), GFP_KERNEL,
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				dev_to_node(dev));
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	if (!ptr)
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		return NULL;
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	switch (type) {
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	case DEVM_IOREMAP:
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		addr = ioremap(offset, size);
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		break;
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	case DEVM_IOREMAP_UC:
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		addr = ioremap_uc(offset, size);
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		break;
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	case DEVM_IOREMAP_WC:
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		addr = ioremap_wc(offset, size);
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		break;
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	case DEVM_IOREMAP_NP:
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		addr = ioremap_np(offset, size);
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		break;
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	}
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	if (addr) {
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		*ptr = addr;
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		devres_add(dev, ptr);
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	} else
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		devres_free(ptr);
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	return addr;
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}
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/**
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 * devm_ioremap - Managed ioremap()
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 * @dev: Generic device to remap IO address for
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 * @offset: Resource address to map
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 * @size: Size of map
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 *
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 * Managed ioremap().  Map is automatically unmapped on driver detach.
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 */
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void __iomem *devm_ioremap(struct device *dev, resource_size_t offset,
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			   resource_size_t size)
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{
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	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP);
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}
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EXPORT_SYMBOL(devm_ioremap);
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/**
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 * devm_ioremap_uc - Managed ioremap_uc()
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 * @dev: Generic device to remap IO address for
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 * @offset: Resource address to map
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 * @size: Size of map
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 *
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 * Managed ioremap_uc().  Map is automatically unmapped on driver detach.
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 */
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void __iomem *devm_ioremap_uc(struct device *dev, resource_size_t offset,
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			      resource_size_t size)
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{
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	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_UC);
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}
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EXPORT_SYMBOL_GPL(devm_ioremap_uc);
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/**
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 * devm_ioremap_wc - Managed ioremap_wc()
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 * @dev: Generic device to remap IO address for
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 * @offset: Resource address to map
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 * @size: Size of map
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 *
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 * Managed ioremap_wc().  Map is automatically unmapped on driver detach.
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 */
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void __iomem *devm_ioremap_wc(struct device *dev, resource_size_t offset,
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			      resource_size_t size)
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{
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	return __devm_ioremap(dev, offset, size, DEVM_IOREMAP_WC);
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}
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EXPORT_SYMBOL(devm_ioremap_wc);
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/**
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 * devm_iounmap - Managed iounmap()
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 * @dev: Generic device to unmap for
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 * @addr: Address to unmap
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 *
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 * Managed iounmap().  @addr must have been mapped using devm_ioremap*().
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 */
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void devm_iounmap(struct device *dev, void __iomem *addr)
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{
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	WARN_ON(devres_release(dev, devm_ioremap_release, devm_ioremap_match,
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			       (__force void *)addr));
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}
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EXPORT_SYMBOL(devm_iounmap);
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static void __iomem *
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__devm_ioremap_resource(struct device *dev, const struct resource *res,
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			enum devm_ioremap_type type)
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{
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	resource_size_t size;
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	void __iomem *dest_ptr;
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	char *pretty_name;
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	int ret;
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	BUG_ON(!dev);
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	if (!res || resource_type(res) != IORESOURCE_MEM) {
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		ret = dev_err_probe(dev, -EINVAL, "invalid resource %pR\n", res);
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		return IOMEM_ERR_PTR(ret);
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	}
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	if (type == DEVM_IOREMAP && res->flags & IORESOURCE_MEM_NONPOSTED)
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		type = DEVM_IOREMAP_NP;
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	size = resource_size(res);
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	if (res->name)
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		pretty_name = devm_kasprintf(dev, GFP_KERNEL, "%s %s",
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					     dev_name(dev), res->name);
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	else
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		pretty_name = devm_kstrdup(dev, dev_name(dev), GFP_KERNEL);
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	if (!pretty_name) {
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		ret = dev_err_probe(dev, -ENOMEM, "can't generate pretty name for resource %pR\n", res);
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		return IOMEM_ERR_PTR(ret);
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	}
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	if (!devm_request_mem_region(dev, res->start, size, pretty_name)) {
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		ret = dev_err_probe(dev, -EBUSY, "can't request region for resource %pR\n", res);
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		return IOMEM_ERR_PTR(ret);
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	}
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	dest_ptr = __devm_ioremap(dev, res->start, size, type);
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	if (!dest_ptr) {
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		devm_release_mem_region(dev, res->start, size);
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		ret = dev_err_probe(dev, -ENOMEM, "ioremap failed for resource %pR\n", res);
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		return IOMEM_ERR_PTR(ret);
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	}
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	return dest_ptr;
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}
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/**
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 * devm_ioremap_resource() - check, request region, and ioremap resource
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 * @dev: generic device to handle the resource for
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 * @res: resource to be handled
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 *
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 * Checks that a resource is a valid memory region, requests the memory
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 * region and ioremaps it. All operations are managed and will be undone
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 * on driver detach.
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 *
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 * Usage example:
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 *
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 *	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
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 *	base = devm_ioremap_resource(&pdev->dev, res);
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 *	if (IS_ERR(base))
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 *		return PTR_ERR(base);
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 *
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 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
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 * on failure.
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 */
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void __iomem *devm_ioremap_resource(struct device *dev,
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				    const struct resource *res)
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{
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	return __devm_ioremap_resource(dev, res, DEVM_IOREMAP);
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}
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EXPORT_SYMBOL(devm_ioremap_resource);
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/**
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 * devm_ioremap_resource_wc() - write-combined variant of
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 *				devm_ioremap_resource()
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 * @dev: generic device to handle the resource for
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 * @res: resource to be handled
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 *
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 * Return: a pointer to the remapped memory or an ERR_PTR() encoded error code
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 * on failure.
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 */
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void __iomem *devm_ioremap_resource_wc(struct device *dev,
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				       const struct resource *res)
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{
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	return __devm_ioremap_resource(dev, res, DEVM_IOREMAP_WC);
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}
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/*
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 * devm_of_iomap - Requests a resource and maps the memory mapped IO
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 *		   for a given device_node managed by a given device
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 *
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 * Checks that a resource is a valid memory region, requests the memory
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 * region and ioremaps it. All operations are managed and will be undone
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 * on driver detach of the device.
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 *
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 * This is to be used when a device requests/maps resources described
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 * by other device tree nodes (children or otherwise).
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 *
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 * @dev:	The device "managing" the resource
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 * @node:       The device-tree node where the resource resides
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 * @index:	index of the MMIO range in the "reg" property
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 * @size:	Returns the size of the resource (pass NULL if not needed)
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 *
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 * Usage example:
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 *
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 *	base = devm_of_iomap(&pdev->dev, node, 0, NULL);
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 *	if (IS_ERR(base))
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 *		return PTR_ERR(base);
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 *
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 * Please Note: This is not a one-to-one replacement for of_iomap() because the
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 * of_iomap() function does not track whether the region is already mapped.  If
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 * two drivers try to map the same memory, the of_iomap() function will succeed
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 * but the devm_of_iomap() function will return -EBUSY.
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 *
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 * Return: a pointer to the requested and mapped memory or an ERR_PTR() encoded
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 * error code on failure.
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 */
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void __iomem *devm_of_iomap(struct device *dev, struct device_node *node, int index,
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			    resource_size_t *size)
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{
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	struct resource res;
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	if (of_address_to_resource(node, index, &res))
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		return IOMEM_ERR_PTR(-EINVAL);
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	if (size)
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		*size = resource_size(&res);
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	return devm_ioremap_resource(dev, &res);
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}
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EXPORT_SYMBOL(devm_of_iomap);
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#ifdef CONFIG_HAS_IOPORT_MAP
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/*
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 * Generic iomap devres
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 */
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static void devm_ioport_map_release(struct device *dev, void *res)
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{
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	ioport_unmap(*(void __iomem **)res);
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}
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static int devm_ioport_map_match(struct device *dev, void *res,
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				 void *match_data)
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{
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	return *(void **)res == match_data;
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}
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/**
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 * devm_ioport_map - Managed ioport_map()
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 * @dev: Generic device to map ioport for
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 * @port: Port to map
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 * @nr: Number of ports to map
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 *
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 * Managed ioport_map().  Map is automatically unmapped on driver
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 * detach.
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 *
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 * Return: a pointer to the remapped memory or NULL on failure.
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 */
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void __iomem *devm_ioport_map(struct device *dev, unsigned long port,
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			       unsigned int nr)
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{
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	void __iomem **ptr, *addr;
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	ptr = devres_alloc_node(devm_ioport_map_release, sizeof(*ptr), GFP_KERNEL,
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				dev_to_node(dev));
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	if (!ptr)
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		return NULL;
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	addr = ioport_map(port, nr);
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	if (addr) {
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		*ptr = addr;
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		devres_add(dev, ptr);
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	} else
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		devres_free(ptr);
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	return addr;
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}
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EXPORT_SYMBOL(devm_ioport_map);
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/**
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 * devm_ioport_unmap - Managed ioport_unmap()
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 * @dev: Generic device to unmap for
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 * @addr: Address to unmap
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 *
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 * Managed ioport_unmap().  @addr must have been mapped using
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 * devm_ioport_map().
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 */
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void devm_ioport_unmap(struct device *dev, void __iomem *addr)
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{
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	WARN_ON(devres_release(dev, devm_ioport_map_release,
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			       devm_ioport_map_match, (__force void *)addr));
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}
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EXPORT_SYMBOL(devm_ioport_unmap);
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#endif /* CONFIG_HAS_IOPORT_MAP */
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static void devm_arch_phys_ac_add_release(struct device *dev, void *res)
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{
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	arch_phys_wc_del(*((int *)res));
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}
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/**
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 * devm_arch_phys_wc_add - Managed arch_phys_wc_add()
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 * @dev: Managed device
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 * @base: Memory base address
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 * @size: Size of memory range
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 *
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 * Adds a WC MTRR using arch_phys_wc_add() and sets up a release callback.
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 * See arch_phys_wc_add() for more information.
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 */
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int devm_arch_phys_wc_add(struct device *dev, unsigned long base, unsigned long size)
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{
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	int *mtrr;
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	int ret;
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	mtrr = devres_alloc_node(devm_arch_phys_ac_add_release, sizeof(*mtrr), GFP_KERNEL,
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				 dev_to_node(dev));
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	if (!mtrr)
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		return -ENOMEM;
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	ret = arch_phys_wc_add(base, size);
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	if (ret < 0) {
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		devres_free(mtrr);
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		return ret;
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	}
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	*mtrr = ret;
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	devres_add(dev, mtrr);
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	return ret;
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}
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EXPORT_SYMBOL(devm_arch_phys_wc_add);
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struct arch_io_reserve_memtype_wc_devres {
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	resource_size_t start;
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	resource_size_t size;
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};
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static void devm_arch_io_free_memtype_wc_release(struct device *dev, void *res)
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{
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	const struct arch_io_reserve_memtype_wc_devres *this = res;
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	arch_io_free_memtype_wc(this->start, this->size);
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}
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/**
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 * devm_arch_io_reserve_memtype_wc - Managed arch_io_reserve_memtype_wc()
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 * @dev: Managed device
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 * @start: Memory base address
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 * @size: Size of memory range
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 *
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 * Reserves a memory range with WC caching using arch_io_reserve_memtype_wc()
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 * and sets up a release callback See arch_io_reserve_memtype_wc() for more
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 * information.
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 */
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int devm_arch_io_reserve_memtype_wc(struct device *dev, resource_size_t start,
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				    resource_size_t size)
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{
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	struct arch_io_reserve_memtype_wc_devres *dr;
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	int ret;
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	dr = devres_alloc_node(devm_arch_io_free_memtype_wc_release, sizeof(*dr), GFP_KERNEL,
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			       dev_to_node(dev));
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	if (!dr)
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		return -ENOMEM;
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	ret = arch_io_reserve_memtype_wc(start, size);
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	if (ret < 0) {
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		devres_free(dr);
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		return ret;
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	}
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	dr->start = start;
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	dr->size = size;
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	devres_add(dev, dr);
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	return ret;
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}
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EXPORT_SYMBOL(devm_arch_io_reserve_memtype_wc);
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