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 */
comedi_to_pci_dev(struct comedi_device * dev)24 struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev)
25 {
26 return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL;
27 }
28 EXPORT_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 */
comedi_pci_enable(struct comedi_device * dev)48 int 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 }
68 EXPORT_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 */
comedi_pci_disable(struct comedi_device * dev)79 void 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 }
89 EXPORT_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 */
comedi_pci_detach(struct comedi_device * dev)105 void 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 }
122 EXPORT_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 */
comedi_pci_auto_config(struct pci_dev * pcidev,struct comedi_driver * driver,unsigned long context)139 int 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 }
145 EXPORT_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 */
comedi_pci_auto_unconfig(struct pci_dev * pcidev)161 void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
162 {
163 comedi_auto_unconfig(&pcidev->dev);
164 }
165 EXPORT_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 */
comedi_pci_driver_register(struct comedi_driver * comedi_driver,struct pci_driver * pci_driver)178 int 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 }
195 EXPORT_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 */
comedi_pci_driver_unregister(struct comedi_driver * comedi_driver,struct pci_driver * pci_driver)206 void 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 }
212 EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister);
213
comedi_pci_init(void)214 static int __init comedi_pci_init(void)
215 {
216 return 0;
217 }
218 module_init(comedi_pci_init);
219
comedi_pci_exit(void)220 static void __exit comedi_pci_exit(void)
221 {
222 }
223 module_exit(comedi_pci_exit);
224
225 MODULE_AUTHOR("https://www.comedi.org");
226 MODULE_DESCRIPTION("Comedi PCI interface module");
227 MODULE_LICENSE("GPL");
228