// SPDX-License-Identifier: GPL-2.0
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irqdomain.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;
}

static int devm_request_result(struct device *dev, int rc, unsigned int irq,
                               irq_handler_t handler, irq_handler_t thread_fn,
                               const char *devname)
{
        if (rc >= 0)
                return rc;

        return dev_err_probe(dev, rc, "request_irq(%u) %ps %ps %s\n",
                             irq, handler, thread_fn, devname ? : "");
}

static 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;
}

/**
 * devm_request_threaded_irq - allocate an interrupt line for a managed device with error logging
 * @dev:        Device to request interrupt for
 * @irq:        Interrupt line to allocate
 * @handler:    Function to be called when the interrupt 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().
 * Interrupts requested with this function will be automatically freed on
 * driver detach.
 *
 * If an interrupt allocated with this function needs to be freed
 * separately, devm_free_irq() must be used.
 *
 * When the request fails, an error message is printed with contextual
 * information (device name, interrupt number, handler functions and
 * error code). Don't add extra error messages at the call sites.
 *
 * Return: 0 on success or a negative error number.
 */
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)
{
        int rc = __devm_request_threaded_irq(dev, irq, handler, thread_fn,
                                             irqflags, devname, dev_id);

        return devm_request_result(dev, rc, irq, handler, thread_fn, devname);
}
EXPORT_SYMBOL(devm_request_threaded_irq);

static 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;
}

/**
 * devm_request_any_context_irq - allocate an interrupt line for a managed device with error logging
 * @dev:        Device to request interrupt for
 * @irq:        Interrupt line to allocate
 * @handler:    Function to be called when the interrupt 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().
 * Interrupts requested with this function will be automatically freed on
 * driver detach.
 *
 * If an interrupt allocated with this function needs to be freed
 * separately, devm_free_irq() must be used.
 *
 * When the request fails, an error message is printed with contextual
 * information (device name, interrupt number, handler functions and
 * error code). Don't add extra error messages at the call sites.
 *
 * Return: IRQC_IS_HARDIRQ or IRQC_IS_NESTED on success, or a negative error
 * number.
 */
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)
{
        int rc = __devm_request_any_context_irq(dev, irq, handler, irqflags,
                                                devname, dev_id);

        return devm_request_result(dev, rc, irq, handler, NULL, devname);
}
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_release(dev, devm_irq_release, devm_irq_match,
                               &match_data));
}
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 */

#ifdef CONFIG_IRQ_DOMAIN
static void devm_irq_domain_remove(struct device *dev, void *res)
{
        struct irq_domain **domain = res;

        irq_domain_remove(*domain);
}

/**
 * devm_irq_domain_instantiate() - Instantiate a new irq domain data for a
 *                                 managed device.
 * @dev:        Device to instantiate the domain for
 * @info:       Domain information pointer pointing to the information for this
 *              domain
 *
 * Return: A pointer to the instantiated irq domain or an ERR_PTR value.
 */
struct irq_domain *devm_irq_domain_instantiate(struct device *dev,
                                               const struct irq_domain_info *info)
{
        struct irq_domain *domain;
        struct irq_domain **dr;

        dr = devres_alloc(devm_irq_domain_remove, sizeof(*dr), GFP_KERNEL);
        if (!dr)
                return ERR_PTR(-ENOMEM);

        domain = irq_domain_instantiate(info);
        if (!IS_ERR(domain)) {
                *dr = domain;
                devres_add(dev, dr);
        } else {
                devres_free(dr);
        }

        return domain;
}
EXPORT_SYMBOL_GPL(devm_irq_domain_instantiate);
#endif /* CONFIG_IRQ_DOMAIN */