drivers/staging/comedi/comedi_pci.c

   1 /*
   2  * comedi_pci.c
   3  * Comedi PCI driver specific functions.
   4  *
   5  * COMEDI - Linux Control and Measurement Device Interface
   6  * Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/interrupt.h>
  21
  22 #include "comedi_pci.h"
  23
  24 /**
  25  * comedi_to_pci_dev() - Return PCI device attached to COMEDI device
  26  * @dev: COMEDI device.
  27  *
  28  * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
  29  * a &struct device embedded in a &struct pci_dev.
  30  *
  31  * Return: Attached PCI device if @dev->hw_dev is non-%NULL.
  32  * Return %NULL if @dev->hw_dev is %NULL.
  33  */
  34 struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev)
  35 {
  36         return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL;
  37 }
  38 EXPORT_SYMBOL_GPL(comedi_to_pci_dev);
  39
  40 /**
  41  * comedi_pci_enable() - Enable the PCI device and request the regions
  42  * @dev: COMEDI device.
  43  *
  44  * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
  45  * a &struct device embedded in a &struct pci_dev.  Enable the PCI device
  46  * and request its regions.  Set @dev->ioenabled to %true if successful,
  47  * otherwise undo what was done.
  48  *
  49  * Calls to comedi_pci_enable() and comedi_pci_disable() cannot be nested.
  50  *
  51  * Return:
  52  *      0 on success,
  53  *      -%ENODEV if @dev->hw_dev is %NULL,
  54  *      -%EBUSY if regions busy,
  55  *      or some negative error number if failed to enable PCI device.
  56  *
  57  */
  58 int comedi_pci_enable(struct comedi_device *dev)
  59 {
  60         struct pci_dev *pcidev = comedi_to_pci_dev(dev);
  61         int rc;
  62
  63         if (!pcidev)
  64                 return -ENODEV;
  65
  66         rc = pci_enable_device(pcidev);
  67         if (rc < 0)
  68                 return rc;
  69
  70         rc = pci_request_regions(pcidev, dev->board_name);
  71         if (rc < 0)
  72                 pci_disable_device(pcidev);
  73         else
  74                 dev->ioenabled = true;
  75
  76         return rc;
  77 }
  78 EXPORT_SYMBOL_GPL(comedi_pci_enable);
  79
  80 /**
  81  * comedi_pci_disable() - Release the regions and disable the PCI device
  82  * @dev: COMEDI device.
  83  *
  84  * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
  85  * a &struct device embedded in a &struct pci_dev.  If the earlier call
  86  * to comedi_pci_enable() was successful, release the PCI device's regions
  87  * and disable it.  Reset @dev->ioenabled back to %false.
  88  */
  89 void comedi_pci_disable(struct comedi_device *dev)
  90 {
  91         struct pci_dev *pcidev = comedi_to_pci_dev(dev);
  92
  93         if (pcidev && dev->ioenabled) {
  94                 pci_release_regions(pcidev);
  95                 pci_disable_device(pcidev);
  96         }
  97         dev->ioenabled = false;
  98 }
  99 EXPORT_SYMBOL_GPL(comedi_pci_disable);
 100
 101 /**
 102  * comedi_pci_detach() - A generic "detach" handler for PCI COMEDI drivers
 103  * @dev: COMEDI device.
 104  *
 105  * COMEDI drivers for PCI devices that need no special clean-up of private data
 106  * and have no ioremapped regions other than that pointed to by @dev->mmio may
 107  * use this function as its "detach" handler called by the COMEDI core when a
 108  * COMEDI device is being detached from the low-level driver.  It may be also
 109  * called from a more specific "detach" handler that does additional clean-up.
 110  *
 111  * Free the IRQ if @dev->irq is non-zero, iounmap @dev->mmio if it is
 112  * non-%NULL, and call comedi_pci_disable() to release the PCI device's regions
 113  * and disable it.
 114  */
 115 void comedi_pci_detach(struct comedi_device *dev)
 116 {
 117         struct pci_dev *pcidev = comedi_to_pci_dev(dev);
 118
 119         if (!pcidev || !dev->ioenabled)
 120                 return;
 121
 122         if (dev->irq) {
 123                 free_irq(dev->irq, dev);
 124                 dev->irq = 0;
 125         }
 126         if (dev->mmio) {
 127                 iounmap(dev->mmio);
 128                 dev->mmio = NULL;
 129         }
 130         comedi_pci_disable(dev);
 131 }
 132 EXPORT_SYMBOL_GPL(comedi_pci_detach);
 133
 134 /**
 135  * comedi_pci_auto_config() - Configure/probe a PCI COMEDI device
 136  * @pcidev: PCI device.
 137  * @driver: Registered COMEDI driver.
 138  * @context: Driver specific data, passed to comedi_auto_config().
 139  *
 140  * Typically called from the pci_driver (*probe) function.  Auto-configure
 141  * a COMEDI device, using the &struct device embedded in *@pcidev as the
 142  * hardware device.  The @context value gets passed through to @driver's
 143  * "auto_attach" handler.  The "auto_attach" handler may call
 144  * comedi_to_pci_dev() on the passed in COMEDI device to recover @pcidev.
 145  *
 146  * Return: The result of calling comedi_auto_config() (0 on success, or
 147  * a negative error number on failure).
 148  */
 149 int comedi_pci_auto_config(struct pci_dev *pcidev,
 150                            struct comedi_driver *driver,
 151                            unsigned long context)
 152 {
 153         return comedi_auto_config(&pcidev->dev, driver, context);
 154 }
 155 EXPORT_SYMBOL_GPL(comedi_pci_auto_config);
 156
 157 /**
 158  * comedi_pci_auto_unconfig() - Unconfigure/remove a PCI COMEDI device
 159  * @pcidev: PCI device.
 160  *
 161  * Typically called from the pci_driver (*remove) function.  Auto-unconfigure
 162  * a COMEDI device attached to this PCI device, using a pointer to the
 163  * &struct device embedded in *@pcidev as the hardware device.  The COMEDI
 164  * driver's "detach" handler will be called during unconfiguration of the
 165  * COMEDI device.
 166  *
 167  * Note that the COMEDI device may have already been unconfigured using the
 168  * %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it
 169  * again should be ignored.
 170  */
 171 void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
 172 {
 173         comedi_auto_unconfig(&pcidev->dev);
 174 }
 175 EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig);
 176
 177 /**
 178  * comedi_pci_driver_register() - Register a PCI COMEDI driver
 179  * @comedi_driver: COMEDI driver to be registered.
 180  * @pci_driver: PCI driver to be registered.
 181  *
 182  * This function is called from the module_init() of PCI COMEDI driver modules
 183  * to register the COMEDI driver and the PCI driver.  Do not call it directly,
 184  * use the module_comedi_pci_driver() helper macro instead.
 185  *
 186  * Return: 0 on success, or a negative error number on failure.
 187  */
 188 int comedi_pci_driver_register(struct comedi_driver *comedi_driver,
 189                                struct pci_driver *pci_driver)
 190 {
 191         int ret;
 192
 193         ret = comedi_driver_register(comedi_driver);
 194         if (ret < 0)
 195                 return ret;
 196
 197         ret = pci_register_driver(pci_driver);
 198         if (ret < 0) {
 199                 comedi_driver_unregister(comedi_driver);
 200                 return ret;
 201         }
 202
 203         return 0;
 204 }
 205 EXPORT_SYMBOL_GPL(comedi_pci_driver_register);
 206
 207 /**
 208  * comedi_pci_driver_unregister() - Unregister a PCI COMEDI driver
 209  * @comedi_driver: COMEDI driver to be unregistered.
 210  * @pci_driver: PCI driver to be unregistered.
 211  *
 212  * This function is called from the module_exit() of PCI COMEDI driver modules
 213  * to unregister the PCI driver and the COMEDI driver.  Do not call it
 214  * directly, use the module_comedi_pci_driver() helper macro instead.
 215  */
 216 void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver,
 217                                   struct pci_driver *pci_driver)
 218 {
 219         pci_unregister_driver(pci_driver);
 220         comedi_driver_unregister(comedi_driver);
 221 }
 222 EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister);
 223
 224 static int __init comedi_pci_init(void)
 225 {
 226         return 0;
 227 }
 228 module_init(comedi_pci_init);
 229
 230 static void __exit comedi_pci_exit(void)
 231 {
 232 }
 233 module_exit(comedi_pci_exit);
 234
 235 MODULE_AUTHOR("http://www.comedi.org");
 236 MODULE_DESCRIPTION("Comedi PCI interface module");
 237 MODULE_LICENSE("GPL");