1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * comedi_pci.c
  4 * Comedi PCI driver specific functions.
  5 *
  6 * COMEDI - Linux Control and Measurement Device Interface
  7 * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
  8 */
  9
 10#include <linux/module.h>
 11#include <linux/interrupt.h>
 12#include <linux/comedi/comedi_pci.h>
 13
 14/**
 15 * comedi_to_pci_dev() - Return PCI device attached to COMEDI device
 16 * @dev: COMEDI device.
 17 *
 18 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 19 * a &struct device embedded in a &struct pci_dev.
 20 *
 21 * Return: Attached PCI device if @dev->hw_dev is non-%NULL.
 22 * Return %NULL if @dev->hw_dev is %NULL.
 23 */
 24struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev)
 25{
 26	return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL;
 27}
 28EXPORT_SYMBOL_GPL(comedi_to_pci_dev);
 29
 30/**
 31 * comedi_pci_enable() - Enable the PCI device and request the regions
 32 * @dev: COMEDI device.
 33 *
 34 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 35 * a &struct device embedded in a &struct pci_dev.  Enable the PCI device
 36 * and request its regions.  Set @dev->ioenabled to %true if successful,
 37 * otherwise undo what was done.
 38 *
 39 * Calls to comedi_pci_enable() and comedi_pci_disable() cannot be nested.
 40 *
 41 * Return:
 42 *	0 on success,
 43 *	-%ENODEV if @dev->hw_dev is %NULL,
 44 *	-%EBUSY if regions busy,
 45 *	or some negative error number if failed to enable PCI device.
 46 *
 47 */
 48int comedi_pci_enable(struct comedi_device *dev)
 49{
 50	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 51	int rc;
 52
 53	if (!pcidev)
 54		return -ENODEV;
 55
 56	rc = pci_enable_device(pcidev);
 57	if (rc < 0)
 58		return rc;
 59
 60	rc = pci_request_regions(pcidev, dev->board_name);
 61	if (rc < 0)
 62		pci_disable_device(pcidev);
 63	else
 64		dev->ioenabled = true;
 65
 66	return rc;
 67}
 68EXPORT_SYMBOL_GPL(comedi_pci_enable);
 69
 70/**
 71 * comedi_pci_disable() - Release the regions and disable the PCI device
 72 * @dev: COMEDI device.
 73 *
 74 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 75 * a &struct device embedded in a &struct pci_dev.  If the earlier call
 76 * to comedi_pci_enable() was successful, release the PCI device's regions
 77 * and disable it.  Reset @dev->ioenabled back to %false.
 78 */
 79void comedi_pci_disable(struct comedi_device *dev)
 80{
 81	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 82
 83	if (pcidev && dev->ioenabled) {
 84		pci_release_regions(pcidev);
 85		pci_disable_device(pcidev);
 86	}
 87	dev->ioenabled = false;
 88}
 89EXPORT_SYMBOL_GPL(comedi_pci_disable);
 90
 91/**
 92 * comedi_pci_detach() - A generic "detach" handler for PCI COMEDI drivers
 93 * @dev: COMEDI device.
 94 *
 95 * COMEDI drivers for PCI devices that need no special clean-up of private data
 96 * and have no ioremapped regions other than that pointed to by @dev->mmio may
 97 * use this function as its "detach" handler called by the COMEDI core when a
 98 * COMEDI device is being detached from the low-level driver.  It may be also
 99 * called from a more specific "detach" handler that does additional clean-up.
100 *
101 * Free the IRQ if @dev->irq is non-zero, iounmap @dev->mmio if it is
102 * non-%NULL, and call comedi_pci_disable() to release the PCI device's regions
103 * and disable it.
104 */
105void comedi_pci_detach(struct comedi_device *dev)
106{
107	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
108
109	if (!pcidev || !dev->ioenabled)
110		return;
111
112	if (dev->irq) {
113		free_irq(dev->irq, dev);
114		dev->irq = 0;
115	}
116	if (dev->mmio) {
117		iounmap(dev->mmio);
118		dev->mmio = NULL;
119	}
120	comedi_pci_disable(dev);
121}
122EXPORT_SYMBOL_GPL(comedi_pci_detach);
123
124/**
125 * comedi_pci_auto_config() - Configure/probe a PCI COMEDI device
126 * @pcidev: PCI device.
127 * @driver: Registered COMEDI driver.
128 * @context: Driver specific data, passed to comedi_auto_config().
129 *
130 * Typically called from the pci_driver (*probe) function.  Auto-configure
131 * a COMEDI device, using the &struct device embedded in *@pcidev as the
132 * hardware device.  The @context value gets passed through to @driver's
133 * "auto_attach" handler.  The "auto_attach" handler may call
134 * comedi_to_pci_dev() on the passed in COMEDI device to recover @pcidev.
135 *
136 * Return: The result of calling comedi_auto_config() (0 on success, or
137 * a negative error number on failure).
138 */
139int comedi_pci_auto_config(struct pci_dev *pcidev,
140			   struct comedi_driver *driver,
141			   unsigned long context)
142{
143	return comedi_auto_config(&pcidev->dev, driver, context);
144}
145EXPORT_SYMBOL_GPL(comedi_pci_auto_config);
146
147/**
148 * comedi_pci_auto_unconfig() - Unconfigure/remove a PCI COMEDI device
149 * @pcidev: PCI device.
150 *
151 * Typically called from the pci_driver (*remove) function.  Auto-unconfigure
152 * a COMEDI device attached to this PCI device, using a pointer to the
153 * &struct device embedded in *@pcidev as the hardware device.  The COMEDI
154 * driver's "detach" handler will be called during unconfiguration of the
155 * COMEDI device.
156 *
157 * Note that the COMEDI device may have already been unconfigured using the
158 * %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it
159 * again should be ignored.
160 */
161void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
162{
163	comedi_auto_unconfig(&pcidev->dev);
164}
165EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig);
166
167/**
168 * comedi_pci_driver_register() - Register a PCI COMEDI driver
169 * @comedi_driver: COMEDI driver to be registered.
170 * @pci_driver: PCI driver to be registered.
171 *
172 * This function is called from the module_init() of PCI COMEDI driver modules
173 * to register the COMEDI driver and the PCI driver.  Do not call it directly,
174 * use the module_comedi_pci_driver() helper macro instead.
175 *
176 * Return: 0 on success, or a negative error number on failure.
177 */
178int comedi_pci_driver_register(struct comedi_driver *comedi_driver,
179			       struct pci_driver *pci_driver)
180{
181	int ret;
182
183	ret = comedi_driver_register(comedi_driver);
184	if (ret < 0)
185		return ret;
186
187	ret = pci_register_driver(pci_driver);
188	if (ret < 0) {
189		comedi_driver_unregister(comedi_driver);
190		return ret;
191	}
192
193	return 0;
194}
195EXPORT_SYMBOL_GPL(comedi_pci_driver_register);
196
197/**
198 * comedi_pci_driver_unregister() - Unregister a PCI COMEDI driver
199 * @comedi_driver: COMEDI driver to be unregistered.
200 * @pci_driver: PCI driver to be unregistered.
201 *
202 * This function is called from the module_exit() of PCI COMEDI driver modules
203 * to unregister the PCI driver and the COMEDI driver.  Do not call it
204 * directly, use the module_comedi_pci_driver() helper macro instead.
205 */
206void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver,
207				  struct pci_driver *pci_driver)
208{
209	pci_unregister_driver(pci_driver);
210	comedi_driver_unregister(comedi_driver);
211}
212EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister);
213
214static int __init comedi_pci_init(void)
215{
216	return 0;
217}
218module_init(comedi_pci_init);
219
220static void __exit comedi_pci_exit(void)
221{
222}
223module_exit(comedi_pci_exit);
224
225MODULE_AUTHOR("https://www.comedi.org");
226MODULE_DESCRIPTION("Comedi PCI interface module");
227MODULE_LICENSE("GPL");