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 */
comedi_to_pci_dev(struct comedi_device * dev)25 struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev)
26 {
27 return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL;
28 }
29 EXPORT_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 */
comedi_pci_enable(struct comedi_device * dev)49 int 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 }
69 EXPORT_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 */
comedi_pci_disable(struct comedi_device * dev)80 void 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 }
90 EXPORT_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 */
comedi_pci_detach(struct comedi_device * dev)106 void 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 }
123 EXPORT_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 */
comedi_pci_auto_config(struct pci_dev * pcidev,struct comedi_driver * driver,unsigned long context)140 int 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 }
146 EXPORT_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 */
comedi_pci_auto_unconfig(struct pci_dev * pcidev)162 void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
163 {
164 comedi_auto_unconfig(&pcidev->dev);
165 }
166 EXPORT_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 */
comedi_pci_driver_register(struct comedi_driver * comedi_driver,struct pci_driver * pci_driver)179 int 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 }
196 EXPORT_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 */
comedi_pci_driver_unregister(struct comedi_driver * comedi_driver,struct pci_driver * pci_driver)207 void 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 }
213 EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister);
214
comedi_pci_init(void)215 static int __init comedi_pci_init(void)
216 {
217 return 0;
218 }
219 module_init(comedi_pci_init);
220
comedi_pci_exit(void)221 static void __exit comedi_pci_exit(void)
222 {
223 }
224 module_exit(comedi_pci_exit);
225
226 MODULE_AUTHOR("https://www.comedi.org");
227 MODULE_DESCRIPTION("Comedi PCI interface module");
228 MODULE_LICENSE("GPL");
229