kernel/irq/devres.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/module.h>
   3 #include <linux/interrupt.h>
   4 #include <linux/irqdomain.h>
   5 #include <linux/device.h>
   6 #include <linux/gfp.h>
   7 #include <linux/irq.h>
   8
   9 #include "internals.h"
  10
  11 /*
  12  * Device resource management aware IRQ request/free implementation.
  13  */
  14 struct irq_devres {
  15         unsigned int irq;
  16         void *dev_id;
  17 };
  18
  19 static void devm_irq_release(struct device *dev, void *res)
  20 {
  21         struct irq_devres *this = res;
  22
  23         free_irq(this->irq, this->dev_id);
  24 }
  25
  26 static int devm_irq_match(struct device *dev, void *res, void *data)
  27 {
  28         struct irq_devres *this = res, *match = data;
  29
  30         return this->irq == match->irq && this->dev_id == match->dev_id;
  31 }
  32
  33 /**
  34  *      devm_request_threaded_irq - allocate an interrupt line for a managed device
  35  *      @dev: device to request interrupt for
  36  *      @irq: Interrupt line to allocate
  37  *      @handler: Function to be called when the IRQ occurs
  38  *      @thread_fn: function to be called in a threaded interrupt context. NULL
  39  *                  for devices which handle everything in @handler
  40  *      @irqflags: Interrupt type flags
  41  *      @devname: An ascii name for the claiming device, dev_name(dev) if NULL
  42  *      @dev_id: A cookie passed back to the handler function
  43  *
  44  *      Except for the extra @dev argument, this function takes the
  45  *      same arguments and performs the same function as
  46  *      request_threaded_irq().  IRQs requested with this function will be
  47  *      automatically freed on driver detach.
  48  *
  49  *      If an IRQ allocated with this function needs to be freed
  50  *      separately, devm_free_irq() must be used.
  51  */
  52 int devm_request_threaded_irq(struct device *dev, unsigned int irq,
  53                               irq_handler_t handler, irq_handler_t thread_fn,
  54                               unsigned long irqflags, const char *devname,
  55                               void *dev_id)
  56 {
  57         struct irq_devres *dr;
  58         int rc;
  59
  60         dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
  61                           GFP_KERNEL);
  62         if (!dr)
  63                 return -ENOMEM;
  64
  65         if (!devname)
  66                 devname = dev_name(dev);
  67
  68         rc = request_threaded_irq(irq, handler, thread_fn, irqflags, devname,
  69                                   dev_id);
  70         if (rc) {
  71                 devres_free(dr);
  72                 return rc;
  73         }
  74
  75         dr->irq = irq;
  76         dr->dev_id = dev_id;
  77         devres_add(dev, dr);
  78
  79         return 0;
  80 }
  81 EXPORT_SYMBOL(devm_request_threaded_irq);
  82
  83 /**
  84  *      devm_request_any_context_irq - allocate an interrupt line for a managed device
  85  *      @dev: device to request interrupt for
  86  *      @irq: Interrupt line to allocate
  87  *      @handler: Function to be called when the IRQ occurs
  88  *      @irqflags: Interrupt type flags
  89  *      @devname: An ascii name for the claiming device, dev_name(dev) if NULL
  90  *      @dev_id: A cookie passed back to the handler function
  91  *
  92  *      Except for the extra @dev argument, this function takes the
  93  *      same arguments and performs the same function as
  94  *      request_any_context_irq().  IRQs requested with this function will be
  95  *      automatically freed on driver detach.
  96  *
  97  *      If an IRQ allocated with this function needs to be freed
  98  *      separately, devm_free_irq() must be used.
  99  */
 100 int devm_request_any_context_irq(struct device *dev, unsigned int irq,
 101                               irq_handler_t handler, unsigned long irqflags,
 102                               const char *devname, void *dev_id)
 103 {
 104         struct irq_devres *dr;
 105         int rc;
 106
 107         dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
 108                           GFP_KERNEL);
 109         if (!dr)
 110                 return -ENOMEM;
 111
 112         if (!devname)
 113                 devname = dev_name(dev);
 114
 115         rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
 116         if (rc < 0) {
 117                 devres_free(dr);
 118                 return rc;
 119         }
 120
 121         dr->irq = irq;
 122         dr->dev_id = dev_id;
 123         devres_add(dev, dr);
 124
 125         return rc;
 126 }
 127 EXPORT_SYMBOL(devm_request_any_context_irq);
 128
 129 /**
 130  *      devm_free_irq - free an interrupt
 131  *      @dev: device to free interrupt for
 132  *      @irq: Interrupt line to free
 133  *      @dev_id: Device identity to free
 134  *
 135  *      Except for the extra @dev argument, this function takes the
 136  *      same arguments and performs the same function as free_irq().
 137  *      This function instead of free_irq() should be used to manually
 138  *      free IRQs allocated with devm_request_irq().
 139  */
 140 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
 141 {
 142         struct irq_devres match_data = { irq, dev_id };
 143
 144         WARN_ON(devres_release(dev, devm_irq_release, devm_irq_match,
 145                                &match_data));
 146 }
 147 EXPORT_SYMBOL(devm_free_irq);
 148
 149 struct irq_desc_devres {
 150         unsigned int from;
 151         unsigned int cnt;
 152 };
 153
 154 static void devm_irq_desc_release(struct device *dev, void *res)
 155 {
 156         struct irq_desc_devres *this = res;
 157
 158         irq_free_descs(this->from, this->cnt);
 159 }
 160
 161 /**
 162  * __devm_irq_alloc_descs - Allocate and initialize a range of irq descriptors
 163  *                          for a managed device
 164  * @dev:        Device to allocate the descriptors for
 165  * @irq:        Allocate for specific irq number if irq >= 0
 166  * @from:       Start the search from this irq number
 167  * @cnt:        Number of consecutive irqs to allocate
 168  * @node:       Preferred node on which the irq descriptor should be allocated
 169  * @owner:      Owning module (can be NULL)
 170  * @affinity:   Optional pointer to an irq_affinity_desc array of size @cnt
 171  *              which hints where the irq descriptors should be allocated
 172  *              and which default affinities to use
 173  *
 174  * Returns the first irq number or error code.
 175  *
 176  * Note: Use the provided wrappers (devm_irq_alloc_desc*) for simplicity.
 177  */
 178 int __devm_irq_alloc_descs(struct device *dev, int irq, unsigned int from,
 179                            unsigned int cnt, int node, struct module *owner,
 180                            const struct irq_affinity_desc *affinity)
 181 {
 182         struct irq_desc_devres *dr;
 183         int base;
 184
 185         dr = devres_alloc(devm_irq_desc_release, sizeof(*dr), GFP_KERNEL);
 186         if (!dr)
 187                 return -ENOMEM;
 188
 189         base = __irq_alloc_descs(irq, from, cnt, node, owner, affinity);
 190         if (base < 0) {
 191                 devres_free(dr);
 192                 return base;
 193         }
 194
 195         dr->from = base;
 196         dr->cnt = cnt;
 197         devres_add(dev, dr);
 198
 199         return base;
 200 }
 201 EXPORT_SYMBOL_GPL(__devm_irq_alloc_descs);
 202
 203 #ifdef CONFIG_GENERIC_IRQ_CHIP
 204 /**
 205  * devm_irq_alloc_generic_chip - Allocate and initialize a generic chip
 206  *                               for a managed device
 207  * @dev:        Device to allocate the generic chip for
 208  * @name:       Name of the irq chip
 209  * @num_ct:     Number of irq_chip_type instances associated with this
 210  * @irq_base:   Interrupt base nr for this chip
 211  * @reg_base:   Register base address (virtual)
 212  * @handler:    Default flow handler associated with this chip
 213  *
 214  * Returns an initialized irq_chip_generic structure. The chip defaults
 215  * to the primary (index 0) irq_chip_type and @handler
 216  */
 217 struct irq_chip_generic *
 218 devm_irq_alloc_generic_chip(struct device *dev, const char *name, int num_ct,
 219                             unsigned int irq_base, void __iomem *reg_base,
 220                             irq_flow_handler_t handler)
 221 {
 222         struct irq_chip_generic *gc;
 223
 224         gc = devm_kzalloc(dev, struct_size(gc, chip_types, num_ct), GFP_KERNEL);
 225         if (gc)
 226                 irq_init_generic_chip(gc, name, num_ct,
 227                                       irq_base, reg_base, handler);
 228
 229         return gc;
 230 }
 231 EXPORT_SYMBOL_GPL(devm_irq_alloc_generic_chip);
 232
 233 struct irq_generic_chip_devres {
 234         struct irq_chip_generic *gc;
 235         u32 msk;
 236         unsigned int clr;
 237         unsigned int set;
 238 };
 239
 240 static void devm_irq_remove_generic_chip(struct device *dev, void *res)
 241 {
 242         struct irq_generic_chip_devres *this = res;
 243
 244         irq_remove_generic_chip(this->gc, this->msk, this->clr, this->set);
 245 }
 246
 247 /**
 248  * devm_irq_setup_generic_chip - Setup a range of interrupts with a generic
 249  *                               chip for a managed device
 250  *
 251  * @dev:        Device to setup the generic chip for
 252  * @gc:         Generic irq chip holding all data
 253  * @msk:        Bitmask holding the irqs to initialize relative to gc->irq_base
 254  * @flags:      Flags for initialization
 255  * @clr:        IRQ_* bits to clear
 256  * @set:        IRQ_* bits to set
 257  *
 258  * Set up max. 32 interrupts starting from gc->irq_base. Note, this
 259  * initializes all interrupts to the primary irq_chip_type and its
 260  * associated handler.
 261  */
 262 int devm_irq_setup_generic_chip(struct device *dev, struct irq_chip_generic *gc,
 263                                 u32 msk, enum irq_gc_flags flags,
 264                                 unsigned int clr, unsigned int set)
 265 {
 266         struct irq_generic_chip_devres *dr;
 267
 268         dr = devres_alloc(devm_irq_remove_generic_chip,
 269                           sizeof(*dr), GFP_KERNEL);
 270         if (!dr)
 271                 return -ENOMEM;
 272
 273         irq_setup_generic_chip(gc, msk, flags, clr, set);
 274
 275         dr->gc = gc;
 276         dr->msk = msk;
 277         dr->clr = clr;
 278         dr->set = set;
 279         devres_add(dev, dr);
 280
 281         return 0;
 282 }
 283 EXPORT_SYMBOL_GPL(devm_irq_setup_generic_chip);
 284 #endif /* CONFIG_GENERIC_IRQ_CHIP */
 285
 286 #ifdef CONFIG_IRQ_DOMAIN
 287 static void devm_irq_domain_remove(struct device *dev, void *res)
 288 {
 289         struct irq_domain **domain = res;
 290
 291         irq_domain_remove(*domain);
 292 }
 293
 294 /**
 295  * devm_irq_domain_instantiate() - Instantiate a new irq domain data for a
 296  *                                 managed device.
 297  * @dev:        Device to instantiate the domain for
 298  * @info:       Domain information pointer pointing to the information for this
 299  *              domain
 300  *
 301  * Return: A pointer to the instantiated irq domain or an ERR_PTR value.
 302  */
 303 struct irq_domain *devm_irq_domain_instantiate(struct device *dev,
 304                                                const struct irq_domain_info *info)
 305 {
 306         struct irq_domain *domain;
 307         struct irq_domain **dr;
 308
 309         dr = devres_alloc(devm_irq_domain_remove, sizeof(*dr), GFP_KERNEL);
 310         if (!dr)
 311                 return ERR_PTR(-ENOMEM);
 312
 313         domain = irq_domain_instantiate(info);
 314         if (!IS_ERR(domain)) {
 315                 *dr = domain;
 316                 devres_add(dev, dr);
 317         } else {
 318                 devres_free(dr);
 319         }
 320
 321         return domain;
 322 }
 323 EXPORT_SYMBOL_GPL(devm_irq_domain_instantiate);
 324 #endif /* CONFIG_IRQ_DOMAIN */