comedi_pci.h revision 7b1f281350ca1ba1f740ced203136d27390b22c1 
1/*
2    comedi/drivers/comedi_pci.h
3    Various PCI functions for drivers.
4
5    Copyright (C) 2007 MEV Ltd. <http://www.mev.co.uk/>
6
7    COMEDI - Linux Control and Measurement Device Interface
8    Copyright (C) 2000 David A. Schleef <ds@schleef.org>
9
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License as published by
12    the Free Software Foundation; either version 2 of the License, or
13    (at your option) any later version.
14
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License for more details.
19
20    You should have received a copy of the GNU General Public License
21    along with this program; if not, write to the Free Software
22    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23
24*/
25
26#ifndef _COMEDI_PCI_H_
27#define _COMEDI_PCI_H_
28
29#include <linux/pci.h>
30
31/*
32 * Called to disable PCI device if PCI device has been enabled, but
33 * PCI regions have not been reserved.
34 *
35 * It only disables the PCI device if the kernel supports reference
36 * counting of PCI enables, otherwise it might stop the device working
37 * in another driver instance.
38 */
39static inline void comedi_pci_disable_no_regions(struct pci_dev *pdev)
40{
41	pci_disable_device(pdev);
42}
43
44/*
45 * Enable the PCI device and request the regions.
46 */
47static inline int comedi_pci_enable(struct pci_dev *pdev, const char *res_name)
48{
49	int rc;
50
51	rc = pci_enable_device(pdev);
52	if (rc < 0)
53		return rc;
54
55	rc = pci_request_regions(pdev, res_name);
56	if (rc < 0)
57		pci_disable_device(pdev);
58
59	return rc;
60}
61
62/*
63 * Release the regions and disable the PCI device.
64 *
65 * This must be matched with a previous successful call to comedi_pci_enable().
66 */
67static inline void comedi_pci_disable(struct pci_dev *pdev)
68{
69	pci_release_regions(pdev);
70	pci_disable_device(pdev);
71}
72
73#endif
74