linuxdebug/kernel/irq/devres.c

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2024-07-16 15:50:57 +02:00
// SPDX-License-Identifier: GPL-2.0
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/gfp.h>
#include <linux/irq.h>
#include "internals.h"
/*
* Device resource management aware IRQ request/free implementation.
*/
struct irq_devres {
unsigned int irq;
void *dev_id;
};
static void devm_irq_release(struct device *dev, void *res)
{
struct irq_devres *this = res;
free_irq(this->irq, this->dev_id);
}
static int devm_irq_match(struct device *dev, void *res, void *data)
{
struct irq_devres *this = res, *match = data;
return this->irq == match->irq && this->dev_id == match->dev_id;
}
/**
* devm_request_threaded_irq - allocate an interrupt line for a managed device
* @dev: device to request interrupt for
* @irq: Interrupt line to allocate
* @handler: Function to be called when the IRQ occurs
* @thread_fn: function to be called in a threaded interrupt context. NULL
* for devices which handle everything in @handler
* @irqflags: Interrupt type flags
* @devname: An ascii name for the claiming device, dev_name(dev) if NULL
* @dev_id: A cookie passed back to the handler function
*
* Except for the extra @dev argument, this function takes the
* same arguments and performs the same function as
* request_threaded_irq(). IRQs requested with this function will be
* automatically freed on driver detach.
*
* If an IRQ allocated with this function needs to be freed
* separately, devm_free_irq() must be used.
*/
int devm_request_threaded_irq(struct device *dev, unsigned int irq,
irq_handler_t handler, irq_handler_t thread_fn,
unsigned long irqflags, const char *devname,
void *dev_id)
{
struct irq_devres *dr;
int rc;
dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
GFP_KERNEL);
if (!dr)
return -ENOMEM;
if (!devname)
devname = dev_name(dev);
rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
dev_id);
if (rc) {
devres_free(dr);
return rc;
}
dr->irq = irq;
dr->dev_id = dev_id;
devres_add(dev, dr);
return 0;
}
EXPORT_SYMBOL(devm_request_threaded_irq);
/**
* devm_request_any_context_irq - allocate an interrupt line for a managed device
* @dev: device to request interrupt for
* @irq: Interrupt line to allocate
* @handler: Function to be called when the IRQ occurs
* @irqflags: Interrupt type flags
* @devname: An ascii name for the claiming device, dev_name(dev) if NULL
* @dev_id: A cookie passed back to the handler function
*
* Except for the extra @dev argument, this function takes the
* same arguments and performs the same function as
* request_any_context_irq(). IRQs requested with this function will be
* automatically freed on driver detach.
*
* If an IRQ allocated with this function needs to be freed
* separately, devm_free_irq() must be used.
*/
int devm_request_any_context_irq(struct device *dev, unsigned int irq,
irq_handler_t handler, unsigned long irqflags,
const char *devname, void *dev_id)
{
struct irq_devres *dr;
int rc;
dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
GFP_KERNEL);
if (!dr)
return -ENOMEM;
if (!devname)
devname = dev_name(dev);
rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
if (rc < 0) {
devres_free(dr);
return rc;
}
dr->irq = irq;
dr->dev_id = dev_id;
devres_add(dev, dr);
return rc;
}
EXPORT_SYMBOL(devm_request_any_context_irq);
/**
* devm_free_irq - free an interrupt
* @dev: device to free interrupt for
* @irq: Interrupt line to free
* @dev_id: Device identity to free
*
* Except for the extra @dev argument, this function takes the
* same arguments and performs the same function as free_irq().
* This function instead of free_irq() should be used to manually
* free IRQs allocated with devm_request_irq().
*/
void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
{
struct irq_devres match_data = { irq, dev_id };
WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
&match_data));
free_irq(irq, dev_id);
}
EXPORT_SYMBOL(devm_free_irq);
struct irq_desc_devres {
unsigned int from;
unsigned int cnt;
};
static void devm_irq_desc_release(struct device *dev, void *res)
{
struct irq_desc_devres *this = res;
irq_free_descs(this->from, this->cnt);
}
/**
* __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
* for a managed device
* @dev: Device to allocate the descriptors for
* @irq: Allocate for specific irq number if irq >= 0
* @from: Start the search from this irq number
* @cnt: Number of consecutive irqs to allocate
* @node: Preferred node on which the irq descriptor should be allocated
* @owner: Owning module (can be NULL)
* @affinity: Optional pointer to an irq_affinity_desc array of size @cnt
* which hints where the irq descriptors should be allocated
* and which default affinities to use
*
* Returns the first irq number or error code.
*
* Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
*/
int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
unsigned int cnt, int node, struct module *owner,
const struct irq_affinity_desc *affinity)
{
struct irq_desc_devres *dr;
int base;
dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
if (!dr)
return -ENOMEM;
base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
if (base < 0) {
devres_free(dr);
return base;
}
dr->from = base;
dr->cnt = cnt;
devres_add(dev, dr);
return base;
}
EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
#ifdef CONFIG_GENERIC_IRQ_CHIP
/**
* devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
* for a managed device
* @dev: Device to allocate the generic chip for
* @name: Name of the irq chip
* @num_ct: Number of irq_chip_type instances associated with this
* @irq_base: Interrupt base nr for this chip
* @reg_base: Register base address (virtual)
* @handler: Default flow handler associated with this chip
*
* Returns an initialized irq_chip_generic structure. The chip defaults
* to the primary (index 0) irq_chip_type and @handler
*/
struct irq_chip_generic *
devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
unsigned int irq_base, void __iomem *reg_base,
irq_flow_handler_t handler)
{
struct irq_chip_generic *gc;
gc = devm_kzalloc(dev, struct_size(gc, chip_types, num_ct), GFP_KERNEL);
if (gc)
irq_init_generic_chip(gc, name, num_ct,
irq_base, reg_base, handler);
return gc;
}
EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
struct irq_generic_chip_devres {
struct irq_chip_generic *gc;
u32 msk;
unsigned int clr;
unsigned int set;
};
static void devm_irq_remove_generic_chip(struct device *dev, void *res)
{
struct irq_generic_chip_devres *this = res;
irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
}
/**
* devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
* chip for a managed device
*
* @dev: Device to setup the generic chip for
* @gc: Generic irq chip holding all data
* @msk: Bitmask holding the irqs to initialize relative to gc->irq_base
* @flags: Flags for initialization
* @clr: IRQ_* bits to clear
* @set: IRQ_* bits to set
*
* Set up max. 32 interrupts starting from gc->irq_base. Note, this
* initializes all interrupts to the primary irq_chip_type and its
* associated handler.
*/
int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
u32 msk, enum irq_gc_flags flags,
unsigned int clr, unsigned int set)
{
struct irq_generic_chip_devres *dr;
dr = devres_alloc(devm_irq_remove_generic_chip,
sizeof(*dr), GFP_KERNEL);
if (!dr)
return -ENOMEM;
irq_setup_generic_chip(gc, msk, flags, clr, set);
dr->gc = gc;
dr->msk = msk;
dr->clr = clr;
dr->set = set;
devres_add(dev, dr);
return 0;
}
EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
#endif /* CONFIG_GENERIC_IRQ_CHIP */