projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 388c8c16 | 2 | /* |
| 704e8953 | 3 | * PCI IRQ handling code |
| 388c8c16 JB |
4 | * |
| 5 | * Copyright (c) 2008 James Bottomley <James.Bottomley@HansenPartnership.com> | |
| 704e8953 | 6 | * Copyright (C) 2017 Christoph Hellwig. |
| 388c8c16 JB |
7 | */ |
| 8 | ||
| 388c8c16 JB |
9 | #include <linux/device.h> |
| 10 | #include <linux/kernel.h> | |
| 363c75db | 11 | #include <linux/export.h> |
| 388c8c16 JB |
12 | #include <linux/pci.h> |
| 13 | ||
| 704e8953 CH |
14 | /** |
| 15 | * pci_request_irq - allocate an interrupt line for a PCI device | |
| 16 | * @dev: PCI device to operate on | |
| 17 | * @nr: device-relative interrupt vector index (0-based). | |
| 18 | * @handler: Function to be called when the IRQ occurs. | |
| 19 | * Primary handler for threaded interrupts. | |
| 20 | * If NULL and thread_fn != NULL the default primary handler is | |
| 21 | * installed. | |
| 22 | * @thread_fn: Function called from the IRQ handler thread | |
| 23 | * If NULL, no IRQ thread is created | |
| 24 | * @dev_id: Cookie passed back to the handler function | |
| 25 | * @fmt: Printf-like format string naming the handler | |
| 26 | * | |
| 27 | * This call allocates interrupt resources and enables the interrupt line and | |
| 28 | * IRQ handling. From the point this call is made @handler and @thread_fn may | |
| 29 | * be invoked. All interrupts requested using this function might be shared. | |
| 30 | * | |
| 31 | * @dev_id must not be NULL and must be globally unique. | |
| 32 | */ | |
| 33 | int pci_request_irq(struct pci_dev *dev, unsigned int nr, irq_handler_t handler, | |
| 34 | irq_handler_t thread_fn, void *dev_id, const char *fmt, ...) | |
| 35 | { | |
| 36 | va_list ap; | |
| 37 | int ret; | |
| 38 | char *devname; | |
| f7368a55 HK |
39 | unsigned long irqflags = IRQF_SHARED; |
| 40 | ||
| 41 | if (!handler) | |
| 42 | irqflags |= IRQF_ONESHOT; | |
| 704e8953 CH |
43 | |
| 44 | va_start(ap, fmt); | |
| 45 | devname = kvasprintf(GFP_KERNEL, fmt, ap); | |
| 46 | va_end(ap); | |
| 2d9cd957 ZH |
47 | if (!devname) |
| 48 | return -ENOMEM; | |
| 704e8953 CH |
49 | |
| 50 | ret = request_threaded_irq(pci_irq_vector(dev, nr), handler, thread_fn, | |
| f7368a55 | 51 | irqflags, devname, dev_id); |
| 704e8953 CH |
52 | if (ret) |
| 53 | kfree(devname); | |
| 54 | return ret; | |
| 55 | } | |
| 56 | EXPORT_SYMBOL(pci_request_irq); | |
| 57 | ||
| 58 | /** | |
| 59 | * pci_free_irq - free an interrupt allocated with pci_request_irq | |
| 60 | * @dev: PCI device to operate on | |
| 61 | * @nr: device-relative interrupt vector index (0-based). | |
| 62 | * @dev_id: Device identity to free | |
| 63 | * | |
| 64 | * Remove an interrupt handler. The handler is removed and if the interrupt | |
| 65 | * line is no longer in use by any driver it is disabled. The caller must | |
| 66 | * ensure the interrupt is disabled on the device before calling this function. | |
| 67 | * The function does not return until any executing interrupts for this IRQ | |
| 68 | * have completed. | |
| 69 | * | |
| 70 | * This function must not be called from interrupt context. | |
| 71 | */ | |
| 72 | void pci_free_irq(struct pci_dev *dev, unsigned int nr, void *dev_id) | |
| 73 | { | |
| 74 | kfree(free_irq(pci_irq_vector(dev, nr), dev_id)); | |
| 75 | } | |
| 76 | EXPORT_SYMBOL(pci_free_irq); |