drivers/dma/of-dma.c - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /*
  * Device tree helpers for DMA request / controller
  *
  * Based on of_gpio.c
  *
  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */

 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_dma.h>

 static LIST_HEAD(of_dma_list);
 static DEFINE_MUTEX(of_dma_lock);

 /**
  * of_dma_find_controller - Get a DMA controller in DT DMA helpers list
  * @dma_spec:	pointer to DMA specifier as found in the device tree
  *
  * Finds a DMA controller with matching device node and number for dma cells
  * in a list of registered DMA controllers. If a match is found a valid pointer
  * to the DMA data stored is retuned. A NULL pointer is returned if no match is
  * found.
  */
 static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec)
 {
 	struct of_dma *ofdma;

 	list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers)
 		if (ofdma->of_node == dma_spec->np)
 			return ofdma;

 	pr_debug("%s: can't find DMA controller %pOF\n", __func__,
 		 dma_spec->np);

 	return NULL;
 }

 /**
  * of_dma_router_xlate - translation function for router devices
  * @dma_spec:	pointer to DMA specifier as found in the device tree
  * @of_dma:	pointer to DMA controller data (router information)
  *
  * The function creates new dma_spec to be passed to the router driver's
  * of_dma_route_allocate() function to prepare a dma_spec which will be used
  * to request channel from the real DMA controller.
  */
 static struct dma_chan *of_dma_router_xlate(struct of_phandle_args *dma_spec,
 					    struct of_dma *ofdma)
 {
 	struct dma_chan		*chan;
 	struct of_dma		*ofdma_target;
 	struct of_phandle_args	dma_spec_target;
 	void			*route_data;

 	/* translate the request for the real DMA controller */
 	memcpy(&dma_spec_target, dma_spec, sizeof(dma_spec_target));
 	route_data = ofdma->of_dma_route_allocate(&dma_spec_target, ofdma);
 	if (IS_ERR(route_data))
 		return NULL;

 	ofdma_target = of_dma_find_controller(&dma_spec_target);
 	if (!ofdma_target) {
 		ofdma->dma_router->route_free(ofdma->dma_router->dev,
 					      route_data);
 		chan = ERR_PTR(-EPROBE_DEFER);
 		goto err;
 	}

 	chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target);
 	if (IS_ERR_OR_NULL(chan)) {
 		ofdma->dma_router->route_free(ofdma->dma_router->dev,
 					      route_data);
 	} else {
 		chan->router = ofdma->dma_router;
 		chan->route_data = route_data;
 	}

 err:
 	/*
 	 * Need to put the node back since the ofdma->of_dma_route_allocate
 	 * has taken it for generating the new, translated dma_spec
 	 */
 	of_node_put(dma_spec_target.np);
 	return chan;
 }

 /**
  * of_dma_controller_register - Register a DMA controller to DT DMA helpers
  * @np:			device node of DMA controller
  * @of_dma_xlate:	translation function which converts a phandle
  *			arguments list into a dma_chan structure
  * @data		pointer to controller specific data to be used by
  *			translation function
  *
  * Returns 0 on success or appropriate errno value on error.
  *
  * Allocated memory should be freed with appropriate of_dma_controller_free()
  * call.
  */
 int of_dma_controller_register(struct device_node *np,
 				struct dma_chan *(*of_dma_xlate)
 				(struct of_phandle_args *, struct of_dma *),
 				void *data)
 {
 	struct of_dma	*ofdma;

 	if (!np || !of_dma_xlate) {
 		pr_err("%s: not enough information provided\n", __func__);
 		return -EINVAL;
 	}

 	ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL);
 	if (!ofdma)
 		return -ENOMEM;

 	ofdma->of_node = np;
 	ofdma->of_dma_xlate = of_dma_xlate;
 	ofdma->of_dma_data = data;

 	/* Now queue of_dma controller structure in list */
 	mutex_lock(&of_dma_lock);
 	list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);
 	mutex_unlock(&of_dma_lock);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(of_dma_controller_register);

 /**
  * of_dma_controller_free - Remove a DMA controller from DT DMA helpers list
  * @np:		device node of DMA controller
  *
  * Memory allocated by of_dma_controller_register() is freed here.
  */
 void of_dma_controller_free(struct device_node *np)
 {
 	struct of_dma *ofdma;

 	mutex_lock(&of_dma_lock);

 	list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers)
 		if (ofdma->of_node == np) {
 			list_del(&ofdma->of_dma_controllers);
 			kfree(ofdma);
 			break;
 		}

 	mutex_unlock(&of_dma_lock);
 }
 EXPORT_SYMBOL_GPL(of_dma_controller_free);

 /**
  * of_dma_router_register - Register a DMA router to DT DMA helpers as a
  *			    controller
  * @np:				device node of DMA router
  * @of_dma_route_allocate:	setup function for the router which need to
  *				modify the dma_spec for the DMA controller to
  *				use and to set up the requested route.
  * @dma_router:			pointer to dma_router structure to be used when
  *				the route need to be free up.
  *
  * Returns 0 on success or appropriate errno value on error.
  *
  * Allocated memory should be freed with appropriate of_dma_controller_free()
  * call.
  */
 int of_dma_router_register(struct device_node *np,
 			   void *(*of_dma_route_allocate)
 			   (struct of_phandle_args *, struct of_dma *),
 			   struct dma_router *dma_router)
 {
 	struct of_dma	*ofdma;

 	if (!np || !of_dma_route_allocate || !dma_router) {
 		pr_err("%s: not enough information provided\n", __func__);
 		return -EINVAL;
 	}

 	ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL);
 	if (!ofdma)
 		return -ENOMEM;

 	ofdma->of_node = np;
 	ofdma->of_dma_xlate = of_dma_router_xlate;
 	ofdma->of_dma_route_allocate = of_dma_route_allocate;
 	ofdma->dma_router = dma_router;

 	/* Now queue of_dma controller structure in list */
 	mutex_lock(&of_dma_lock);
 	list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);
 	mutex_unlock(&of_dma_lock);

 	return 0;
 }
 EXPORT_SYMBOL_GPL(of_dma_router_register);

 /**
  * of_dma_match_channel - Check if a DMA specifier matches name
  * @np:		device node to look for DMA channels
  * @name:	channel name to be matched
  * @index:	index of DMA specifier in list of DMA specifiers
  * @dma_spec:	pointer to DMA specifier as found in the device tree
  *
  * Check if the DMA specifier pointed to by the index in a list of DMA
  * specifiers, matches the name provided. Returns 0 if the name matches and
  * a valid pointer to the DMA specifier is found. Otherwise returns -ENODEV.
  */
 static int of_dma_match_channel(struct device_node *np, const char *name,
 				int index, struct of_phandle_args *dma_spec)
 {
 	const char *s;

 	if (of_property_read_string_index(np, "dma-names", index, &s))
 		return -ENODEV;

 	if (strcmp(name, s))
 		return -ENODEV;

 	if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
 				       dma_spec))
 		return -ENODEV;

 	return 0;
 }

 /**
  * of_dma_get_mcode_addr - Get the DMA micro code buffer address.
  * @np:		device node of DMA controller
  *
  * Return the physical address.
  */
 unsigned int of_dma_get_mcode_addr(struct device_node *np)
 {
 	unsigned int addr = 0;
 	const __be32	*prop;

 	prop = of_get_property(np, "#dma-mcode-addr", NULL);
 	if (prop)
 		addr = be32_to_cpup(prop);

 	return addr;
 }
 EXPORT_SYMBOL_GPL(of_dma_get_mcode_addr);

 /**
  * of_dma_secure_dma_ch- Get the DMA micro code buffer address.
  * @np:		device node of DMA controller
  *
  * Return the physical address.
  */
 bool of_dma_secure_mode(struct device_node *np)
 {
 	bool ret = 0;
 	const __be32	*prop;

 	prop = of_get_property(np, "#dma-secure-mode", NULL);
 	if (prop)
 		ret = be32_to_cpup(prop);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(of_dma_secure_mode);

 /**
  * of_dma_get_arwrapper_address - Get the DMA WAPPER AR address
  * @np:		device node of DMA controller
  * @num:	DMA channel thread number
  *
  * Return the virtual address.
  */
 void __iomem *of_dma_get_arwrapper_address(struct device_node *np, unsigned int num)
 {
 	const __be32 *reg_list;
 	unsigned int length, count;

 	reg_list = of_get_property(np, "dma-arwrapper", &length);
 	count = (unsigned int)(length / sizeof(unsigned int));

 	if (!reg_list || num >= count)
 		return NULL;

 	return ioremap(be32_to_cpup(reg_list + num), SZ_32);
 }
 EXPORT_SYMBOL_GPL(of_dma_get_arwrapper_address);

 /**
  * of_dma_get_arwrapper_address - Get the DMA WAPPER AW address
  * @np:		device node of DMA controller
  * @num:	DMA channel thread number
  *
  * Return the virtual address.
  */
 void __iomem *of_dma_get_awwrapper_address(struct device_node *np, unsigned int num)
 {
 	const __be32 *reg_list;
 	unsigned int length, count;

 	reg_list = of_get_property(np, "dma-awwrapper", &length);
 	count = (unsigned int)(length / sizeof(unsigned int));

 	if (!reg_list || num >= count)
 		return NULL;

 	return ioremap(be32_to_cpup(reg_list + num), SZ_32);
 }
 EXPORT_SYMBOL_GPL(of_dma_get_awwrapper_address);

 /**
  * of_dma_get_arwrapper_address - Get the DMA WAPPER AR address of DMA instruction
  * @np:		device node of DMA controller
  *
  * Return the virtual address.
  */
 void __iomem *of_dma_get_instwrapper_address(struct device_node *np)
 {
 	const __be32 *reg_list;
 	int ret = 0;

 	reg_list = of_get_property(np, "dma-instwrapper", NULL);

 	if (!reg_list)
 		return NULL;

 	ret = be32_to_cpup(reg_list);
 	if (!ret)
 		return NULL;

 	return ioremap(ret, SZ_32);
 }
 EXPORT_SYMBOL_GPL(of_dma_get_instwrapper_address);

 /**
  * of_dma_get_arwrapper_address - Get the DMA WAPPER availableilable
  * @np:		device node of DMA controller
  *
  */
 bool of_dma_get_wrapper_available(struct device_node *np)
 {
 	const __be32 *reg_list;
 	int ret = 0;

 	reg_list = of_get_property(np, "dma-instwrapper", NULL);

 	if (!reg_list)
 		return false;

 	ret = be32_to_cpup(reg_list);
 	if (ret)
 		return true;
 	else
 		return false;
 }
 EXPORT_SYMBOL_GPL(of_dma_get_wrapper_available);

 /**
  * of_dma_get_arwrapper_address - Get the DMA WAPPER availableilable
  * @np:		device node of DMA controller
  *
  */
 u64 of_dma_get_mask(struct device_node *np, char *name)
 {
 	int bit_cnt = 0;

 	of_property_read_u32(np, name, &bit_cnt);

 	if (bit_cnt)
 		return ((u64)1 << bit_cnt) - 1;
 	else
 		return -1;
 }
 EXPORT_SYMBOL_GPL(of_dma_get_mask);

 /**
  * of_dma_request_slave_channel - Get the DMA slave channel
  * @np:		device node to get DMA request from
  * @name:	name of desired channel
  *
  * Returns pointer to appropriate DMA channel on success or an error pointer.
  */
 struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
 					      const char *name)
 {
 	struct of_phandle_args	dma_spec;
 	struct of_dma		*ofdma;
 	struct dma_chan		*chan;
 	int			count, i, start;
 	int			ret_no_channel = -ENODEV;
 	static atomic_t		last_index;

 	if (!np || !name) {
 		pr_err("%s: not enough information provided\n", __func__);
 		return ERR_PTR(-ENODEV);
 	}

 	/* Silently fail if there is not even the "dmas" property */
 	if (!of_find_property(np, "dmas", NULL))
 		return ERR_PTR(-ENODEV);

 	count = of_property_count_strings(np, "dma-names");
 	if (count < 0) {
 		pr_err("%s: dma-names property of node '%pOF' missing or empty\n",
 			__func__, np);
 		return ERR_PTR(-ENODEV);
 	}

 	/*
 	 * approximate an average distribution across multiple
 	 * entries with the same name
 	 */
 	start = atomic_inc_return(&last_index);
 	for (i = 0; i < count; i++) {
 		if (of_dma_match_channel(np, name,
 					 (i + start) % count,
 					 &dma_spec))
 			continue;

 		mutex_lock(&of_dma_lock);
 		ofdma = of_dma_find_controller(&dma_spec);

 		if (ofdma) {
 			chan = ofdma->of_dma_xlate(&dma_spec, ofdma);
 		} else {
 			ret_no_channel = -EPROBE_DEFER;
 			chan = NULL;
 		}

 		mutex_unlock(&of_dma_lock);

 		of_node_put(dma_spec.np);

 		if (chan)
 			return chan;
 	}

 	return ERR_PTR(ret_no_channel);
 }
 EXPORT_SYMBOL_GPL(of_dma_request_slave_channel);

 /**
  * of_dma_simple_xlate - Simple DMA engine translation function
  * @dma_spec:	pointer to DMA specifier as found in the device tree
  * @of_dma:	pointer to DMA controller data
  *
  * A simple translation function for devices that use a 32-bit value for the
  * filter_param when calling the DMA engine dma_request_channel() function.
  * Note that this translation function requires that #dma-cells is equal to 1
  * and the argument of the dma specifier is the 32-bit filter_param. Returns
  * pointer to appropriate dma channel on success or NULL on error.
  */
 struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
 						struct of_dma *ofdma)
 {
 	int count = dma_spec->args_count;
 	struct of_dma_filter_info *info = ofdma->of_dma_data;

 	if (!info || !info->filter_fn)
 		return NULL;

 	if (count != 1)
 		return NULL;

 	return dma_request_channel(info->dma_cap, info->filter_fn,
 			&dma_spec->args[0]);
 }
 EXPORT_SYMBOL_GPL(of_dma_simple_xlate);

 /**
  * of_dma_xlate_by_chan_id - Translate dt property to DMA channel by channel id
  * @dma_spec:	pointer to DMA specifier as found in the device tree
  * @of_dma:	pointer to DMA controller data
  *
  * This function can be used as the of xlate callback for DMA driver which wants
  * to match the channel based on the channel id. When using this xlate function
  * the #dma-cells propety of the DMA controller dt node needs to be set to 1.
  * The data parameter of of_dma_controller_register must be a pointer to the
  * dma_device struct the function should match upon.
  *
  * Returns pointer to appropriate dma channel on success or NULL on error.
  */
 struct dma_chan *of_dma_xlate_by_chan_id(struct of_phandle_args *dma_spec,
 					 struct of_dma *ofdma)
 {
 	struct dma_device *dev = ofdma->of_dma_data;
 	struct dma_chan *chan, *candidate = NULL;

 	if (!dev || dma_spec->args_count != 1)
 		return NULL;

 	list_for_each_entry(chan, &dev->channels, device_node)
 		if (chan->chan_id == dma_spec->args[0]) {
 			candidate = chan;
 			break;
 		}

 	if (!candidate)
 		return NULL;

 	return dma_get_slave_channel(candidate);
 }
 EXPORT_SYMBOL_GPL(of_dma_xlate_by_chan_id);

 bool of_dma_multi_irq(struct device_node *np)
 {
 	bool ret = 0;
 	const __be32	*prop;

 	prop = of_get_property(np, "#dma-multi-irq", NULL);
 	if (prop)
 		ret = be32_to_cpup(prop);

 	return ret;
 }
 EXPORT_SYMBOL_GPL(of_dma_multi_irq);
	/*
	* Device tree helpers for DMA request / controller
	*
	* Based on of_gpio.c
	*
	* Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*/

	#include <linux/device.h>
	#include <linux/err.h>
	#include <linux/module.h>
	#include <linux/mutex.h>
	#include <linux/slab.h>
	#include <linux/of.h>
	#include <linux/of_dma.h>

	static LIST_HEAD(of_dma_list);
	static DEFINE_MUTEX(of_dma_lock);

	/**
	* of_dma_find_controller - Get a DMA controller in DT DMA helpers list
	* @dma_spec: pointer to DMA specifier as found in the device tree
	*
	* Finds a DMA controller with matching device node and number for dma cells
	* in a list of registered DMA controllers. If a match is found a valid pointer
	* to the DMA data stored is retuned. A NULL pointer is returned if no match is
	* found.
	*/
	static struct of_dma of_dma_find_controller(struct of_phandle_args dma_spec)
	{
	struct of_dma *ofdma;

	list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers)
	if (ofdma->of_node == dma_spec->np)
	return ofdma;

	pr_debug("%s: can't find DMA controller %pOF\n", __func__,
	dma_spec->np);

	return NULL;
	}

	/**
	* of_dma_router_xlate - translation function for router devices
	* @dma_spec: pointer to DMA specifier as found in the device tree
	* @of_dma: pointer to DMA controller data (router information)
	*
	* The function creates new dma_spec to be passed to the router driver's
	* of_dma_route_allocate() function to prepare a dma_spec which will be used
	* to request channel from the real DMA controller.
	*/
	static struct dma_chan of_dma_router_xlate(struct of_phandle_args dma_spec,
	struct of_dma *ofdma)
	{
	struct dma_chan *chan;
	struct of_dma *ofdma_target;
	struct of_phandle_args dma_spec_target;
	void *route_data;

	/* translate the request for the real DMA controller */
	memcpy(&dma_spec_target, dma_spec, sizeof(dma_spec_target));
	route_data = ofdma->of_dma_route_allocate(&dma_spec_target, ofdma);
	if (IS_ERR(route_data))
	return NULL;

	ofdma_target = of_dma_find_controller(&dma_spec_target);
	if (!ofdma_target) {
	ofdma->dma_router->route_free(ofdma->dma_router->dev,
	route_data);
	chan = ERR_PTR(-EPROBE_DEFER);
	goto err;
	}

	chan = ofdma_target->of_dma_xlate(&dma_spec_target, ofdma_target);
	if (IS_ERR_OR_NULL(chan)) {
	ofdma->dma_router->route_free(ofdma->dma_router->dev,
	route_data);
	} else {
	chan->router = ofdma->dma_router;
	chan->route_data = route_data;
	}

	err:
	/*
	* Need to put the node back since the ofdma->of_dma_route_allocate
	* has taken it for generating the new, translated dma_spec
	*/
	of_node_put(dma_spec_target.np);
	return chan;
	}

	/**
	* of_dma_controller_register - Register a DMA controller to DT DMA helpers
	* @np: device node of DMA controller
	* @of_dma_xlate: translation function which converts a phandle
	* arguments list into a dma_chan structure
	* @data pointer to controller specific data to be used by
	* translation function
	*
	* Returns 0 on success or appropriate errno value on error.
	*
	* Allocated memory should be freed with appropriate of_dma_controller_free()
	* call.
	*/
	int of_dma_controller_register(struct device_node *np,
	struct dma_chan (of_dma_xlate)
	(struct of_phandle_args , struct of_dma ),
	void *data)
	{
	struct of_dma *ofdma;

	if (!np \|\| !of_dma_xlate) {
	pr_err("%s: not enough information provided\n", __func__);
	return -EINVAL;
	}

	ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL);
	if (!ofdma)
	return -ENOMEM;

	ofdma->of_node = np;
	ofdma->of_dma_xlate = of_dma_xlate;
	ofdma->of_dma_data = data;

	/* Now queue of_dma controller structure in list */
	mutex_lock(&of_dma_lock);
	list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);
	mutex_unlock(&of_dma_lock);

	return 0;
	}
	EXPORT_SYMBOL_GPL(of_dma_controller_register);

	/**
	* of_dma_controller_free - Remove a DMA controller from DT DMA helpers list
	* @np: device node of DMA controller
	*
	* Memory allocated by of_dma_controller_register() is freed here.
	*/
	void of_dma_controller_free(struct device_node *np)
	{
	struct of_dma *ofdma;

	mutex_lock(&of_dma_lock);

	list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers)
	if (ofdma->of_node == np) {
	list_del(&ofdma->of_dma_controllers);
	kfree(ofdma);
	break;
	}

	mutex_unlock(&of_dma_lock);
	}
	EXPORT_SYMBOL_GPL(of_dma_controller_free);

	/**
	* of_dma_router_register - Register a DMA router to DT DMA helpers as a
	* controller
	* @np: device node of DMA router
	* @of_dma_route_allocate: setup function for the router which need to
	* modify the dma_spec for the DMA controller to
	* use and to set up the requested route.
	* @dma_router: pointer to dma_router structure to be used when
	* the route need to be free up.
	*
	* Returns 0 on success or appropriate errno value on error.
	*
	* Allocated memory should be freed with appropriate of_dma_controller_free()
	* call.
	*/
	int of_dma_router_register(struct device_node *np,
	void (of_dma_route_allocate)
	(struct of_phandle_args , struct of_dma ),
	struct dma_router *dma_router)
	{
	struct of_dma *ofdma;

	if (!np \|\| !of_dma_route_allocate \|\| !dma_router) {
	pr_err("%s: not enough information provided\n", __func__);
	return -EINVAL;
	}

	ofdma = kzalloc(sizeof(*ofdma), GFP_KERNEL);
	if (!ofdma)
	return -ENOMEM;

	ofdma->of_node = np;
	ofdma->of_dma_xlate = of_dma_router_xlate;
	ofdma->of_dma_route_allocate = of_dma_route_allocate;
	ofdma->dma_router = dma_router;

	/* Now queue of_dma controller structure in list */
	mutex_lock(&of_dma_lock);
	list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);
	mutex_unlock(&of_dma_lock);

	return 0;
	}
	EXPORT_SYMBOL_GPL(of_dma_router_register);

	/**
	* of_dma_match_channel - Check if a DMA specifier matches name
	* @np: device node to look for DMA channels
	* @name: channel name to be matched
	* @index: index of DMA specifier in list of DMA specifiers
	* @dma_spec: pointer to DMA specifier as found in the device tree
	*
	* Check if the DMA specifier pointed to by the index in a list of DMA
	* specifiers, matches the name provided. Returns 0 if the name matches and
	* a valid pointer to the DMA specifier is found. Otherwise returns -ENODEV.
	*/
	static int of_dma_match_channel(struct device_node np, const char name,
	int index, struct of_phandle_args *dma_spec)
	{
	const char *s;

	if (of_property_read_string_index(np, "dma-names", index, &s))
	return -ENODEV;

	if (strcmp(name, s))
	return -ENODEV;

	if (of_parse_phandle_with_args(np, "dmas", "#dma-cells", index,
	dma_spec))
	return -ENODEV;

	return 0;
	}

	/**
	* of_dma_get_mcode_addr - Get the DMA micro code buffer address.
	* @np: device node of DMA controller
	*
	* Return the physical address.
	*/
	unsigned int of_dma_get_mcode_addr(struct device_node *np)
	{
	unsigned int addr = 0;
	const __be32 *prop;

	prop = of_get_property(np, "#dma-mcode-addr", NULL);
	if (prop)
	addr = be32_to_cpup(prop);

	return addr;
	}
	EXPORT_SYMBOL_GPL(of_dma_get_mcode_addr);

	/**
	* of_dma_secure_dma_ch- Get the DMA micro code buffer address.
	* @np: device node of DMA controller
	*
	* Return the physical address.
	*/
	bool of_dma_secure_mode(struct device_node *np)
	{
	bool ret = 0;
	const __be32 *prop;

	prop = of_get_property(np, "#dma-secure-mode", NULL);
	if (prop)
	ret = be32_to_cpup(prop);

	return ret;
	}
	EXPORT_SYMBOL_GPL(of_dma_secure_mode);

	/**
	* of_dma_get_arwrapper_address - Get the DMA WAPPER AR address
	* @np: device node of DMA controller
	* @num: DMA channel thread number
	*
	* Return the virtual address.
	*/
	void __iomem of_dma_get_arwrapper_address(struct device_node np, unsigned int num)
	{
	const __be32 *reg_list;
	unsigned int length, count;

	reg_list = of_get_property(np, "dma-arwrapper", &length);
	count = (unsigned int)(length / sizeof(unsigned int));

	if (!reg_list \|\| num >= count)
	return NULL;

	return ioremap(be32_to_cpup(reg_list + num), SZ_32);
	}
	EXPORT_SYMBOL_GPL(of_dma_get_arwrapper_address);

	/**
	* of_dma_get_arwrapper_address - Get the DMA WAPPER AW address
	* @np: device node of DMA controller
	* @num: DMA channel thread number
	*
	* Return the virtual address.
	*/
	void __iomem of_dma_get_awwrapper_address(struct device_node np, unsigned int num)
	{
	const __be32 *reg_list;
	unsigned int length, count;

	reg_list = of_get_property(np, "dma-awwrapper", &length);
	count = (unsigned int)(length / sizeof(unsigned int));

	if (!reg_list \|\| num >= count)
	return NULL;

	return ioremap(be32_to_cpup(reg_list + num), SZ_32);
	}
	EXPORT_SYMBOL_GPL(of_dma_get_awwrapper_address);

	/**
	* of_dma_get_arwrapper_address - Get the DMA WAPPER AR address of DMA instruction
	* @np: device node of DMA controller
	*
	* Return the virtual address.
	*/
	void __iomem of_dma_get_instwrapper_address(struct device_node np)
	{
	const __be32 *reg_list;
	int ret = 0;

	reg_list = of_get_property(np, "dma-instwrapper", NULL);

	if (!reg_list)
	return NULL;

	ret = be32_to_cpup(reg_list);
	if (!ret)
	return NULL;

	return ioremap(ret, SZ_32);
	}
	EXPORT_SYMBOL_GPL(of_dma_get_instwrapper_address);

	/**
	* of_dma_get_arwrapper_address - Get the DMA WAPPER availableilable
	* @np: device node of DMA controller
	*
	*/
	bool of_dma_get_wrapper_available(struct device_node *np)
	{
	const __be32 *reg_list;
	int ret = 0;

	reg_list = of_get_property(np, "dma-instwrapper", NULL);

	if (!reg_list)
	return false;

	ret = be32_to_cpup(reg_list);
	if (ret)
	return true;
	else
	return false;
	}
	EXPORT_SYMBOL_GPL(of_dma_get_wrapper_available);

	/**
	* of_dma_get_arwrapper_address - Get the DMA WAPPER availableilable
	* @np: device node of DMA controller
	*
	*/
	u64 of_dma_get_mask(struct device_node np, char name)
	{
	int bit_cnt = 0;

	of_property_read_u32(np, name, &bit_cnt);

	if (bit_cnt)
	return ((u64)1 << bit_cnt) - 1;
	else
	return -1;
	}
	EXPORT_SYMBOL_GPL(of_dma_get_mask);

	/**
	* of_dma_request_slave_channel - Get the DMA slave channel
	* @np: device node to get DMA request from
	* @name: name of desired channel
	*
	* Returns pointer to appropriate DMA channel on success or an error pointer.
	*/
	struct dma_chan of_dma_request_slave_channel(struct device_node np,
	const char *name)
	{
	struct of_phandle_args dma_spec;
	struct of_dma *ofdma;
	struct dma_chan *chan;
	int count, i, start;
	int ret_no_channel = -ENODEV;
	static atomic_t last_index;

	if (!np \|\| !name) {
	pr_err("%s: not enough information provided\n", __func__);
	return ERR_PTR(-ENODEV);
	}

	/* Silently fail if there is not even the "dmas" property */
	if (!of_find_property(np, "dmas", NULL))
	return ERR_PTR(-ENODEV);

	count = of_property_count_strings(np, "dma-names");
	if (count < 0) {
	pr_err("%s: dma-names property of node '%pOF' missing or empty\n",
	__func__, np);
	return ERR_PTR(-ENODEV);
	}

	/*
	* approximate an average distribution across multiple
	* entries with the same name
	*/
	start = atomic_inc_return(&last_index);
	for (i = 0; i < count; i++) {
	if (of_dma_match_channel(np, name,
	(i + start) % count,
	&dma_spec))
	continue;

	mutex_lock(&of_dma_lock);
	ofdma = of_dma_find_controller(&dma_spec);

	if (ofdma) {
	chan = ofdma->of_dma_xlate(&dma_spec, ofdma);
	} else {
	ret_no_channel = -EPROBE_DEFER;
	chan = NULL;
	}

	mutex_unlock(&of_dma_lock);

	of_node_put(dma_spec.np);

	if (chan)
	return chan;
	}

	return ERR_PTR(ret_no_channel);
	}
	EXPORT_SYMBOL_GPL(of_dma_request_slave_channel);

	/**
	* of_dma_simple_xlate - Simple DMA engine translation function
	* @dma_spec: pointer to DMA specifier as found in the device tree
	* @of_dma: pointer to DMA controller data
	*
	* A simple translation function for devices that use a 32-bit value for the
	* filter_param when calling the DMA engine dma_request_channel() function.
	* Note that this translation function requires that #dma-cells is equal to 1
	* and the argument of the dma specifier is the 32-bit filter_param. Returns
	* pointer to appropriate dma channel on success or NULL on error.
	*/
	struct dma_chan of_dma_simple_xlate(struct of_phandle_args dma_spec,
	struct of_dma *ofdma)
	{
	int count = dma_spec->args_count;
	struct of_dma_filter_info *info = ofdma->of_dma_data;

	if (!info \|\| !info->filter_fn)
	return NULL;

	if (count != 1)
	return NULL;

	return dma_request_channel(info->dma_cap, info->filter_fn,
	&dma_spec->args[0]);
	}
	EXPORT_SYMBOL_GPL(of_dma_simple_xlate);

	/**
	* of_dma_xlate_by_chan_id - Translate dt property to DMA channel by channel id
	* @dma_spec: pointer to DMA specifier as found in the device tree
	* @of_dma: pointer to DMA controller data
	*
	* This function can be used as the of xlate callback for DMA driver which wants
	* to match the channel based on the channel id. When using this xlate function
	* the #dma-cells propety of the DMA controller dt node needs to be set to 1.
	* The data parameter of of_dma_controller_register must be a pointer to the
	* dma_device struct the function should match upon.
	*
	* Returns pointer to appropriate dma channel on success or NULL on error.
	*/
	struct dma_chan of_dma_xlate_by_chan_id(struct of_phandle_args dma_spec,
	struct of_dma *ofdma)
	{
	struct dma_device *dev = ofdma->of_dma_data;
	struct dma_chan chan, candidate = NULL;

	if (!dev \|\| dma_spec->args_count != 1)
	return NULL;

	list_for_each_entry(chan, &dev->channels, device_node)
	if (chan->chan_id == dma_spec->args[0]) {
	candidate = chan;
	break;
	}

	if (!candidate)
	return NULL;

	return dma_get_slave_channel(candidate);
	}
	EXPORT_SYMBOL_GPL(of_dma_xlate_by_chan_id);

	bool of_dma_multi_irq(struct device_node *np)
	{
	bool ret = 0;
	const __be32 *prop;

	prop = of_get_property(np, "#dma-multi-irq", NULL);
	if (prop)
	ret = be32_to_cpup(prop);

	return ret;
	}
	EXPORT_SYMBOL_GPL(of_dma_multi_irq);