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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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 */ 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); 213 214 static int __init comedi_pci_init(void) 215 { 216 return 0; 217 } 218 module_init(comedi_pci_init); 219 220 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