linux/kernel/irq/devres.c
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   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/module.h>
   3#include <linux/interrupt.h>
   4#include <linux/device.h>
   5#include <linux/gfp.h>
   6#include <linux/irq.h>
   7
   8#include "internals.h"
   9
  10/*
  11 * Device resource management aware IRQ request/free implementation.
  12 */
  13struct irq_devres {
  14        unsigned int irq;
  15        void *dev_id;
  16};
  17
  18static void devm_irq_release(struct device *dev, void *res)
  19{
  20        struct irq_devres *this = res;
  21
  22        free_irq(this->irq, this->dev_id);
  23}
  24
  25static int devm_irq_match(struct device *dev, void *res, void *data)
  26{
  27        struct irq_devres *this = res, *match = data;
  28
  29        return this->irq == match->irq && this->dev_id == match->dev_id;
  30}
  31
  32/**
  33 *      devm_request_threaded_irq - allocate an interrupt line for a managed device
  34 *      @dev: device to request interrupt for
  35 *      @irq: Interrupt line to allocate
  36 *      @handler: Function to be called when the IRQ occurs
  37 *      @thread_fn: function to be called in a threaded interrupt context. NULL
  38 *                  for devices which handle everything in @handler
  39 *      @irqflags: Interrupt type flags
  40 *      @devname: An ascii name for the claiming device, dev_name(dev) if NULL
  41 *      @dev_id: A cookie passed back to the handler function
  42 *
  43 *      Except for the extra @dev argument, this function takes the
  44 *      same arguments and performs the same function as
  45 *      request_threaded_irq().  IRQs requested with this function will be
  46 *      automatically freed on driver detach.
  47 *
  48 *      If an IRQ allocated with this function needs to be freed
  49 *      separately, devm_free_irq() must be used.
  50 */
  51int devm_request_threaded_irq(struct device *dev, unsigned int irq,
  52                              irq_handler_t handler, irq_handler_t thread_fn,
  53                              unsigned long irqflags, const char *devname,
  54                              void *dev_id)
  55{
  56        struct irq_devres *dr;
  57        int rc;
  58
  59        dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
  60                          GFP_KERNEL);
  61        if (!dr)
  62                return -ENOMEM;
  63
  64        if (!devname)
  65                devname = dev_name(dev);
  66
  67        rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
  68                                  dev_id);
  69        if (rc) {
  70                devres_free(dr);
  71                return rc;
  72        }
  73
  74        dr->irq = irq;
  75        dr->dev_id = dev_id;
  76        devres_add(dev, dr);
  77
  78        return 0;
  79}
  80EXPORT_SYMBOL(devm_request_threaded_irq);
  81
  82/**
  83 *      devm_request_any_context_irq - allocate an interrupt line for a managed device
  84 *      @dev: device to request interrupt for
  85 *      @irq: Interrupt line to allocate
  86 *      @handler: Function to be called when the IRQ occurs
  87 *      @thread_fn: function to be called in a threaded interrupt context. NULL
  88 *                  for devices which handle everything in @handler
  89 *      @irqflags: Interrupt type flags
  90 *      @devname: An ascii name for the claiming device, dev_name(dev) if NULL
  91 *      @dev_id: A cookie passed back to the handler function
  92 *
  93 *      Except for the extra @dev argument, this function takes the
  94 *      same arguments and performs the same function as
  95 *      request_any_context_irq().  IRQs requested with this function will be
  96 *      automatically freed on driver detach.
  97 *
  98 *      If an IRQ allocated with this function needs to be freed
  99 *      separately, devm_free_irq() must be used.
 100 */
 101int devm_request_any_context_irq(struct device *dev, unsigned int irq,
 102                              irq_handler_t handler, unsigned long irqflags,
 103                              const char *devname, void *dev_id)
 104{
 105        struct irq_devres *dr;
 106        int rc;
 107
 108        dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
 109                          GFP_KERNEL);
 110        if (!dr)
 111                return -ENOMEM;
 112
 113        if (!devname)
 114                devname = dev_name(dev);
 115
 116        rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
 117        if (rc < 0) {
 118                devres_free(dr);
 119                return rc;
 120        }
 121
 122        dr->irq = irq;
 123        dr->dev_id = dev_id;
 124        devres_add(dev, dr);
 125
 126        return rc;
 127}
 128EXPORT_SYMBOL(devm_request_any_context_irq);
 129
 130/**
 131 *      devm_free_irq - free an interrupt
 132 *      @dev: device to free interrupt for
 133 *      @irq: Interrupt line to free
 134 *      @dev_id: Device identity to free
 135 *
 136 *      Except for the extra @dev argument, this function takes the
 137 *      same arguments and performs the same function as free_irq().
 138 *      This function instead of free_irq() should be used to manually
 139 *      free IRQs allocated with devm_request_irq().
 140 */
 141void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
 142{
 143        struct irq_devres match_data = { irq, dev_id };
 144
 145        WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
 146                               &match_data));
 147        free_irq(irq, dev_id);
 148}
 149EXPORT_SYMBOL(devm_free_irq);
 150
 151struct irq_desc_devres {
 152        unsigned int from;
 153        unsigned int cnt;
 154};
 155
 156static void devm_irq_desc_release(struct device *dev, void *res)
 157{
 158        struct irq_desc_devres *this = res;
 159
 160        irq_free_descs(this->from, this->cnt);
 161}
 162
 163/**
 164 * __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
 165 *                          for a managed device
 166 * @dev:        Device to allocate the descriptors for
 167 * @irq:        Allocate for specific irq number if irq >= 0
 168 * @from:       Start the search from this irq number
 169 * @cnt:        Number of consecutive irqs to allocate
 170 * @node:       Preferred node on which the irq descriptor should be allocated
 171 * @owner:      Owning module (can be NULL)
 172 * @affinity:   Optional pointer to an affinity mask array of size @cnt
 173 *              which hints where the irq descriptors should be allocated
 174 *              and which default affinities to use
 175 *
 176 * Returns the first irq number or error code.
 177 *
 178 * Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
 179 */
 180int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 181                           unsigned int cnt, int node, struct module *owner,
 182                           const struct cpumask *affinity)
 183{
 184        struct irq_desc_devres *dr;
 185        int base;
 186
 187        dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
 188        if (!dr)
 189                return -ENOMEM;
 190
 191        base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
 192        if (base < 0) {
 193                devres_free(dr);
 194                return base;
 195        }
 196
 197        dr->from = base;
 198        dr->cnt = cnt;
 199        devres_add(dev, dr);
 200
 201        return base;
 202}
 203EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
 204
 205#ifdef CONFIG_GENERIC_IRQ_CHIP
 206/**
 207 * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
 208 *                               for a managed device
 209 * @dev:        Device to allocate the generic chip for
 210 * @name:       Name of the irq chip
 211 * @num_ct:     Number of irq_chip_type instances associated with this
 212 * @irq_base:   Interrupt base nr for this chip
 213 * @reg_base:   Register base address (virtual)
 214 * @handler:    Default flow handler associated with this chip
 215 *
 216 * Returns an initialized irq_chip_generic structure. The chip defaults
 217 * to the primary (index 0) irq_chip_type and @handler
 218 */
 219struct irq_chip_generic *
 220devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
 221                            unsigned int irq_base, void __iomem *reg_base,
 222                            irq_flow_handler_t handler)
 223{
 224        struct irq_chip_generic *gc;
 225        unsigned long sz = sizeof(*gc) + num_ct * sizeof(struct irq_chip_type);
 226
 227        gc = devm_kzalloc(dev, sz, GFP_KERNEL);
 228        if (gc)
 229                irq_init_generic_chip(gc, name, num_ct,
 230                                      irq_base, reg_base, handler);
 231
 232        return gc;
 233}
 234EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
 235
 236struct irq_generic_chip_devres {
 237        struct irq_chip_generic *gc;
 238        u32 msk;
 239        unsigned int clr;
 240        unsigned int set;
 241};
 242
 243static void devm_irq_remove_generic_chip(struct device *dev, void *res)
 244{
 245        struct irq_generic_chip_devres *this = res;
 246
 247        irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
 248}
 249
 250/**
 251 * devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
 252 *                               chip for a managed device
 253 *
 254 * @dev:        Device to setup the generic chip for
 255 * @gc:         Generic irq chip holding all data
 256 * @msk:        Bitmask holding the irqs to initialize relative to gc->irq_base
 257 * @flags:      Flags for initialization
 258 * @clr:        IRQ_* bits to clear
 259 * @set:        IRQ_* bits to set
 260 *
 261 * Set up max. 32 interrupts starting from gc->irq_base. Note, this
 262 * initializes all interrupts to the primary irq_chip_type and its
 263 * associated handler.
 264 */
 265int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
 266                                u32 msk, enum irq_gc_flags flags,
 267                                unsigned int clr, unsigned int set)
 268{
 269        struct irq_generic_chip_devres *dr;
 270
 271        dr = devres_alloc(devm_irq_remove_generic_chip,
 272                          sizeof(*dr), GFP_KERNEL);
 273        if (!dr)
 274                return -ENOMEM;
 275
 276        irq_setup_generic_chip(gc, msk, flags, clr, set);
 277
 278        dr->gc = gc;
 279        dr->msk = msk;
 280        dr->clr = clr;
 281        dr->set = set;
 282        devres_add(dev, dr);
 283
 284        return 0;
 285}
 286EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
 287#endif /* CONFIG_GENERIC_IRQ_CHIP */
 288