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
 13#include "comedi_pci.h"
 14
 15/**
 16 * comedi_to_pci_dev() - Return PCI device attached to COMEDI device
 17 * @dev: COMEDI device.
 18 *
 19 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 20 * a &struct device embedded in a &struct pci_dev.
 21 *
 22 * Return: Attached PCI device if @dev->hw_dev is non-%NULL.
 23 * Return %NULL if @dev->hw_dev is %NULL.
 24 */
 25struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev)
 26{
 27	return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL;
 28}
 29EXPORT_SYMBOL_GPL(comedi_to_pci_dev);
 30
 31/**
 32 * comedi_pci_enable() - Enable the PCI device and request the regions
 33 * @dev: COMEDI device.
 34 *
 35 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 36 * a &struct device embedded in a &struct pci_dev.  Enable the PCI device
 37 * and request its regions.  Set @dev->ioenabled to %true if successful,
 38 * otherwise undo what was done.
 39 *
 40 * Calls to comedi_pci_enable() and comedi_pci_disable() cannot be nested.
 41 *
 42 * Return:
 43 *	0 on success,
 44 *	-%ENODEV if @dev->hw_dev is %NULL,
 45 *	-%EBUSY if regions busy,
 46 *	or some negative error number if failed to enable PCI device.
 47 *
 48 */
 49int comedi_pci_enable(struct comedi_device *dev)
 50{
 51	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 52	int rc;
 53
 54	if (!pcidev)
 55		return -ENODEV;
 56
 57	rc = pci_enable_device(pcidev);
 58	if (rc < 0)
 59		return rc;
 60
 61	rc = pci_request_regions(pcidev, dev->board_name);
 62	if (rc < 0)
 63		pci_disable_device(pcidev);
 64	else
 65		dev->ioenabled = true;
 66
 67	return rc;
 68}
 69EXPORT_SYMBOL_GPL(comedi_pci_enable);
 70
 71/**
 72 * comedi_pci_disable() - Release the regions and disable the PCI device
 73 * @dev: COMEDI device.
 74 *
 75 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 76 * a &struct device embedded in a &struct pci_dev.  If the earlier call
 77 * to comedi_pci_enable() was successful, release the PCI device's regions
 78 * and disable it.  Reset @dev->ioenabled back to %false.
 79 */
 80void comedi_pci_disable(struct comedi_device *dev)
 81{
 82	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 83
 84	if (pcidev && dev->ioenabled) {
 85		pci_release_regions(pcidev);
 86		pci_disable_device(pcidev);
 87	}
 88	dev->ioenabled = false;
 89}
 90EXPORT_SYMBOL_GPL(comedi_pci_disable);
 91
 92/**
 93 * comedi_pci_detach() - A generic "detach" handler for PCI COMEDI drivers
 94 * @dev: COMEDI device.
 95 *
 96 * COMEDI drivers for PCI devices that need no special clean-up of private data
 97 * and have no ioremapped regions other than that pointed to by @dev->mmio may
 98 * use this function as its "detach" handler called by the COMEDI core when a
 99 * COMEDI device is being detached from the low-level driver.  It may be also
100 * called from a more specific "detach" handler that does additional clean-up.
101 *
102 * Free the IRQ if @dev->irq is non-zero, iounmap @dev->mmio if it is
103 * non-%NULL, and call comedi_pci_disable() to release the PCI device's regions
104 * and disable it.
105 */
106void comedi_pci_detach(struct comedi_device *dev)
107{
108	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
109
110	if (!pcidev || !dev->ioenabled)
111		return;
112
113	if (dev->irq) {
114		free_irq(dev->irq, dev);
115		dev->irq = 0;
116	}
117	if (dev->mmio) {
118		iounmap(dev->mmio);
119		dev->mmio = NULL;
120	}
121	comedi_pci_disable(dev);
122}
123EXPORT_SYMBOL_GPL(comedi_pci_detach);
124
125/**
126 * comedi_pci_auto_config() - Configure/probe a PCI COMEDI device
127 * @pcidev: PCI device.
128 * @driver: Registered COMEDI driver.
129 * @context: Driver specific data, passed to comedi_auto_config().
130 *
131 * Typically called from the pci_driver (*probe) function.  Auto-configure
132 * a COMEDI device, using the &struct device embedded in *@pcidev as the
133 * hardware device.  The @context value gets passed through to @driver's
134 * "auto_attach" handler.  The "auto_attach" handler may call
135 * comedi_to_pci_dev() on the passed in COMEDI device to recover @pcidev.
136 *
137 * Return: The result of calling comedi_auto_config() (0 on success, or
138 * a negative error number on failure).
139 */
140int comedi_pci_auto_config(struct pci_dev *pcidev,
141			   struct comedi_driver *driver,
142			   unsigned long context)
143{
144	return comedi_auto_config(&pcidev->dev, driver, context);
145}
146EXPORT_SYMBOL_GPL(comedi_pci_auto_config);
147
148/**
149 * comedi_pci_auto_unconfig() - Unconfigure/remove a PCI COMEDI device
150 * @pcidev: PCI device.
151 *
152 * Typically called from the pci_driver (*remove) function.  Auto-unconfigure
153 * a COMEDI device attached to this PCI device, using a pointer to the
154 * &struct device embedded in *@pcidev as the hardware device.  The COMEDI
155 * driver's "detach" handler will be called during unconfiguration of the
156 * COMEDI device.
157 *
158 * Note that the COMEDI device may have already been unconfigured using the
159 * %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it
160 * again should be ignored.
161 */
162void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
163{
164	comedi_auto_unconfig(&pcidev->dev);
165}
166EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig);
167
168/**
169 * comedi_pci_driver_register() - Register a PCI COMEDI driver
170 * @comedi_driver: COMEDI driver to be registered.
171 * @pci_driver: PCI driver to be registered.
172 *
173 * This function is called from the module_init() of PCI COMEDI driver modules
174 * to register the COMEDI driver and the PCI driver.  Do not call it directly,
175 * use the module_comedi_pci_driver() helper macro instead.
176 *
177 * Return: 0 on success, or a negative error number on failure.
178 */
179int comedi_pci_driver_register(struct comedi_driver *comedi_driver,
180			       struct pci_driver *pci_driver)
181{
182	int ret;
183
184	ret = comedi_driver_register(comedi_driver);
185	if (ret < 0)
186		return ret;
187
188	ret = pci_register_driver(pci_driver);
189	if (ret < 0) {
190		comedi_driver_unregister(comedi_driver);
191		return ret;
192	}
193
194	return 0;
195}
196EXPORT_SYMBOL_GPL(comedi_pci_driver_register);
197
198/**
199 * comedi_pci_driver_unregister() - Unregister a PCI COMEDI driver
200 * @comedi_driver: COMEDI driver to be unregistered.
201 * @pci_driver: PCI driver to be unregistered.
202 *
203 * This function is called from the module_exit() of PCI COMEDI driver modules
204 * to unregister the PCI driver and the COMEDI driver.  Do not call it
205 * directly, use the module_comedi_pci_driver() helper macro instead.
206 */
207void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver,
208				  struct pci_driver *pci_driver)
209{
210	pci_unregister_driver(pci_driver);
211	comedi_driver_unregister(comedi_driver);
212}
213EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister);
214
215static int __init comedi_pci_init(void)
216{
217	return 0;
218}
219module_init(comedi_pci_init);
220
221static void __exit comedi_pci_exit(void)
222{
223}
224module_exit(comedi_pci_exit);
225
226MODULE_AUTHOR("https://www.comedi.org");
227MODULE_DESCRIPTION("Comedi PCI interface module");
228MODULE_LICENSE("GPL");