Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932117AbdDMHH1 (ORCPT ); Thu, 13 Apr 2017 03:07:27 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:36687 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756190AbdDMHHW (ORCPT ); Thu, 13 Apr 2017 03:07:22 -0400 From: Christoph Hellwig To: Thomas Gleixner , Bjorn Helgaas Cc: linux-pci@vger.kernel.org, linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/4] PCI/irq: add pci_request_irq and pci_free_irq helpers Date: Thu, 13 Apr 2017 09:06:42 +0200 Message-Id: <20170413070643.32165-4-hch@lst.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170413070643.32165-1-hch@lst.de> References: <20170413070643.32165-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4167 Lines: 115 These are small wrappers around request_threaded_irq and free_irq, which dynamically allocate space for the device name so that drivers don't need to keep static buffers for these around. Additionally it works with device-relative vector numbers to make the usage easier, and force the IRQF_SHARED flag on given that it has no runtime overhead and should be supported by all PCI devices. Signed-off-by: Christoph Hellwig --- drivers/pci/irq.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++- include/linux/pci.h | 6 ++++++ 2 files changed, 66 insertions(+), 1 deletion(-) diff --git a/drivers/pci/irq.c b/drivers/pci/irq.c index 6684f153ab57..53e7f30d9461 100644 --- a/drivers/pci/irq.c +++ b/drivers/pci/irq.c @@ -1,7 +1,8 @@ /* - * PCI IRQ failure handing code + * PCI IRQ handing code * * Copyright (c) 2008 James Bottomley + * Copyright (C) 2017 Christoph Hellwig. */ #include @@ -59,3 +60,61 @@ enum pci_lost_interrupt_reason pci_lost_interrupt(struct pci_dev *pdev) return PCI_LOST_IRQ_NO_INFORMATION; } EXPORT_SYMBOL(pci_lost_interrupt); + +/** + * pci_request_irq - allocate an interrupt line for a PCI device + * @dev: PCI device to operate on + * @nr: device-relative interrupt vector index (0-based). + * @handler: Function to be called when the IRQ occurs. + * Primary handler for threaded interrupts. + * If NULL and thread_fn != NULL the default primary handler is + * installed. + * @thread_fn: Function called from the irq handler thread + * If NULL, no irq thread is created + * @dev_id: Cookie passed back to the handler function + * @fmt: Printf-like format string naming the handler + * + * This call allocates interrupt resources and enables the interrupt line and + * IRQ handling. From the point this call is made @handler and @thread_fn may + * be invoked. All interrupt requsted using this function might be shared. + * + * @dev_id must not ne NULL and be globally unique. + */ +int pci_request_irq(struct pci_dev *dev, unsigned int nr, irq_handler_t handler, + irq_handler_t thread_fn, void *dev_id, const char *fmt, ...) +{ + va_list ap; + int ret; + char *devname; + + va_start(ap, fmt); + devname = kvasprintf(GFP_KERNEL, fmt, ap); + va_end(ap); + + ret = request_threaded_irq(pci_irq_vector(dev, nr), handler, thread_fn, + IRQF_SHARED, devname, dev_id); + if (ret) + kfree(devname); + return ret; +} +EXPORT_SYMBOL(pci_request_irq); + +/** + * pci_free_irq - free an interrupt allocated with pci_request_irq + * @dev: PCI device to operate on + * @nr: device-relative interrupt vector index (0-based). + * @dev_id: Device identity to free + * + * Remove an interrupt handler. The handler is removed and if the interrupt + * line is no longer in use by any driver it is disabled. The caller must + * ensure the interrupt is disabled on the device before calling this function. + * The function does not return until any executing interrupts for this IRQ + * have completed. + * + * This function must not be called from interrupt context. + */ +void pci_free_irq(struct pci_dev *dev, unsigned int nr, void *dev_id) +{ + kfree(free_irq(pci_irq_vector(dev, nr), dev_id)); +} +EXPORT_SYMBOL(pci_free_irq); diff --git a/include/linux/pci.h b/include/linux/pci.h index eb3da1a04e6c..b23f81b583ab 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -28,6 +28,7 @@ #include #include #include +#include #include #include #include @@ -1072,6 +1073,11 @@ int pci_select_bars(struct pci_dev *dev, unsigned long flags); bool pci_device_is_present(struct pci_dev *pdev); void pci_ignore_hotplug(struct pci_dev *dev); +int __printf(6, 7) pci_request_irq(struct pci_dev *dev, unsigned int nr, + irq_handler_t handler, irq_handler_t thread_fn, void *dev_id, + const char *fmt, ...); +void pci_free_irq(struct pci_dev *dev, unsigned int nr, void *dev_id); + /* ROM control related routines */ int pci_enable_rom(struct pci_dev *pdev); void pci_disable_rom(struct pci_dev *pdev); -- 2.11.0