// SPDX-License-Identifier: GPL-2.0+ /* * comedi_pci.c * Comedi PCI driver specific functions. * * COMEDI - Linux Control and Measurement Device Interface * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org> */ #include <linux/module.h> #include <linux/interrupt.h> #include <linux/comedi/comedi_pci.h> /** * comedi_to_pci_dev() - Return PCI device attached to COMEDI device * @dev: COMEDI device. * * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a * a &struct device embedded in a &struct pci_dev. * * Return: Attached PCI device if @dev->hw_dev is non-%NULL. * Return %NULL if @dev->hw_dev is %NULL. */ struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev) { return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL; } EXPORT_SYMBOL_GPL(comedi_to_pci_dev); /** * comedi_pci_enable() - Enable the PCI device and request the regions * @dev: COMEDI device. * * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a * a &struct device embedded in a &struct pci_dev. Enable the PCI device * and request its regions. Set @dev->ioenabled to %true if successful, * otherwise undo what was done. * * Calls to comedi_pci_enable() and comedi_pci_disable() cannot be nested. * * Return: * 0 on success, * -%ENODEV if @dev->hw_dev is %NULL, * -%EBUSY if regions busy, * or some negative error number if failed to enable PCI device. * */ int comedi_pci_enable(struct comedi_device *dev) { struct pci_dev *pcidev = comedi_to_pci_dev(dev); int rc; if (!pcidev) return -ENODEV; rc = pci_enable_device(pcidev); if (rc < 0) return rc; rc = pci_request_regions(pcidev, dev->board_name); if (rc < 0) pci_disable_device(pcidev); else dev->ioenabled = true; return rc; } EXPORT_SYMBOL_GPL(comedi_pci_enable); /** * comedi_pci_disable() - Release the regions and disable the PCI device * @dev: COMEDI device. * * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a * a &struct device embedded in a &struct pci_dev. If the earlier call * to comedi_pci_enable() was successful, release the PCI device's regions * and disable it. Reset @dev->ioenabled back to %false. */ void comedi_pci_disable(struct comedi_device *dev) { struct pci_dev *pcidev = comedi_to_pci_dev(dev); if (pcidev && dev->ioenabled) { pci_release_regions(pcidev); pci_disable_device(pcidev); } dev->ioenabled = false; } EXPORT_SYMBOL_GPL(comedi_pci_disable); /** * comedi_pci_detach() - A generic "detach" handler for PCI COMEDI drivers * @dev: COMEDI device. * * COMEDI drivers for PCI devices that need no special clean-up of private data * and have no ioremapped regions other than that pointed to by @dev->mmio may * use this function as its "detach" handler called by the COMEDI core when a * COMEDI device is being detached from the low-level driver. It may be also * called from a more specific "detach" handler that does additional clean-up. * * Free the IRQ if @dev->irq is non-zero, iounmap @dev->mmio if it is * non-%NULL, and call comedi_pci_disable() to release the PCI device's regions * and disable it. */ void comedi_pci_detach(struct comedi_device *dev) { struct pci_dev *pcidev = comedi_to_pci_dev(dev); if (!pcidev || !dev->ioenabled) return; if (dev->irq) { free_irq(dev->irq, dev); dev->irq = 0; } if (dev->mmio) { iounmap(dev->mmio); dev->mmio = NULL; } comedi_pci_disable(dev); } EXPORT_SYMBOL_GPL(comedi_pci_detach); /** * comedi_pci_auto_config() - Configure/probe a PCI COMEDI device * @pcidev: PCI device. * @driver: Registered COMEDI driver. * @context: Driver specific data, passed to comedi_auto_config(). * * Typically called from the pci_driver (*probe) function. Auto-configure * a COMEDI device, using the &struct device embedded in *@pcidev as the * hardware device. The @context value gets passed through to @driver's * "auto_attach" handler. The "auto_attach" handler may call * comedi_to_pci_dev() on the passed in COMEDI device to recover @pcidev. * * Return: The result of calling comedi_auto_config() (0 on success, or * a negative error number on failure). */ int comedi_pci_auto_config(struct pci_dev *pcidev, struct comedi_driver *driver, unsigned long context) { return comedi_auto_config(&pcidev->dev, driver, context); } EXPORT_SYMBOL_GPL(comedi_pci_auto_config); /** * comedi_pci_auto_unconfig() - Unconfigure/remove a PCI COMEDI device * @pcidev: PCI device. * * Typically called from the pci_driver (*remove) function. Auto-unconfigure * a COMEDI device attached to this PCI device, using a pointer to the * &struct device embedded in *@pcidev as the hardware device. The COMEDI * driver's "detach" handler will be called during unconfiguration of the * COMEDI device. * * Note that the COMEDI device may have already been unconfigured using the * %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it * again should be ignored. */ void comedi_pci_auto_unconfig(struct pci_dev *pcidev) { comedi_auto_unconfig(&pcidev->dev); } EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig); /** * comedi_pci_driver_register() - Register a PCI COMEDI driver * @comedi_driver: COMEDI driver to be registered. * @pci_driver: PCI driver to be registered. * * This function is called from the module_init() of PCI COMEDI driver modules * to register the COMEDI driver and the PCI driver. Do not call it directly, * use the module_comedi_pci_driver() helper macro instead. * * Return: 0 on success, or a negative error number on failure. */ int comedi_pci_driver_register(struct comedi_driver *comedi_driver, struct pci_driver *pci_driver) { int ret; ret = comedi_driver_register(comedi_driver); if (ret < 0) return ret; ret = pci_register_driver(pci_driver); if (ret < 0) { comedi_driver_unregister(comedi_driver); return ret; } return 0; } EXPORT_SYMBOL_GPL(comedi_pci_driver_register); /** * comedi_pci_driver_unregister() - Unregister a PCI COMEDI driver * @comedi_driver: COMEDI driver to be unregistered. * @pci_driver: PCI driver to be unregistered. * * This function is called from the module_exit() of PCI COMEDI driver modules * to unregister the PCI driver and the COMEDI driver. Do not call it * directly, use the module_comedi_pci_driver() helper macro instead. */ void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver, struct pci_driver *pci_driver) { pci_unregister_driver(pci_driver); comedi_driver_unregister(comedi_driver); } EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister); static int __init comedi_pci_init(void) { return 0; } module_init(comedi_pci_init); static void __exit comedi_pci_exit(void) { } module_exit(comedi_pci_exit); MODULE_AUTHOR("https://www.comedi.org"); MODULE_DESCRIPTION("Comedi PCI interface module"); MODULE_LICENSE("GPL"