kernel/irq/devres.c

   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  */
  13 struct irq_devres {
  14         unsigned int irq;
  15         void *dev_id;
  16 };
  17
  18 static 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
  25 static 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  */
  51 int 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 }
  80 EXPORT_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  *      @irqflags: Interrupt type flags
  88  *      @devname: An ascii name for the claiming device, dev_name(dev) if NULL
  89  *      @dev_id: A cookie passed back to the handler function
  90  *
  91  *      Except for the extra @dev argument, this function takes the
  92  *      same arguments and performs the same function as
  93  *      request_any_context_irq().  IRQs requested with this function will be
  94  *      automatically freed on driver detach.
  95  *
  96  *      If an IRQ allocated with this function needs to be freed
  97  *      separately, devm_free_irq() must be used.
  98  */
  99 int devm_request_any_context_irq(struct device *dev, unsigned int irq,
 100                               irq_handler_t handler, unsigned long irqflags,
 101                               const char *devname, void *dev_id)
 102 {
 103         struct irq_devres *dr;
 104         int rc;
 105
 106         dr = devres_alloc(devm_irq_release, sizeof(struct irq_devres),
 107                           GFP_KERNEL);
 108         if (!dr)
 109                 return -ENOMEM;
 110
 111         if (!devname)
 112                 devname = dev_name(dev);
 113
 114         rc = request_any_context_irq(irq, handler, irqflags, devname, dev_id);
 115         if (rc < 0) {
 116                 devres_free(dr);
 117                 return rc;
 118         }
 119
 120         dr->irq = irq;
 121         dr->dev_id = dev_id;
 122         devres_add(dev, dr);
 123
 124         return rc;
 125 }
 126 EXPORT_SYMBOL(devm_request_any_context_irq);
 127
 128 /**
 129  *      devm_free_irq - free an interrupt
 130  *      @dev: device to free interrupt for
 131  *      @irq: Interrupt line to free
 132  *      @dev_id: Device identity to free
 133  *
 134  *      Except for the extra @dev argument, this function takes the
 135  *      same arguments and performs the same function as free_irq().
 136  *      This function instead of free_irq() should be used to manually
 137  *      free IRQs allocated with devm_request_irq().
 138  */
 139 void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id)
 140 {
 141         struct irq_devres match_data = { irq, dev_id };
 142
 143         WARN_ON(devres_destroy(dev, devm_irq_release, devm_irq_match,
 144                                &match_data));
 145         free_irq(irq, dev_id);
 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 */