linuxdebug/drivers/comedi/comedi_pci.c

228 lines
6.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* comedi_pci.c
* Comedi PCI driver specific functions.
*
* COMEDI - Linux Control and Measurement Device Interface
* Copyright (C) 1997-2000 David A. Schleef <ds@schleef.org>
*/
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/comedi/comedi_pci.h>
/**
* comedi_to_pci_dev() - Return PCI device attached to COMEDI device
* @dev: COMEDI device.
*
* Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
* a &struct device embedded in a &struct pci_dev.
*
* Return: Attached PCI device if @dev->hw_dev is non-%NULL.
* Return %NULL if @dev->hw_dev is %NULL.
*/
struct pci_dev *comedi_to_pci_dev(struct comedi_device *dev)
{
return dev->hw_dev ? to_pci_dev(dev->hw_dev) : NULL;
}
EXPORT_SYMBOL_GPL(comedi_to_pci_dev);
/**
* comedi_pci_enable() - Enable the PCI device and request the regions
* @dev: COMEDI device.
*
* Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
* a &struct device embedded in a &struct pci_dev. Enable the PCI device
* and request its regions. Set @dev->ioenabled to %true if successful,
* otherwise undo what was done.
*
* Calls to comedi_pci_enable() and comedi_pci_disable() cannot be nested.
*
* Return:
* 0 on success,
* -%ENODEV if @dev->hw_dev is %NULL,
* -%EBUSY if regions busy,
* or some negative error number if failed to enable PCI device.
*
*/
int comedi_pci_enable(struct comedi_device *dev)
{
struct pci_dev *pcidev = comedi_to_pci_dev(dev);
int rc;
if (!pcidev)
return -ENODEV;
rc = pci_enable_device(pcidev);
if (rc < 0)
return rc;
rc = pci_request_regions(pcidev, dev->board_name);
if (rc < 0)
pci_disable_device(pcidev);
else
dev->ioenabled = true;
return rc;
}
EXPORT_SYMBOL_GPL(comedi_pci_enable);
/**
* comedi_pci_disable() - Release the regions and disable the PCI device
* @dev: COMEDI device.
*
* Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
* a &struct device embedded in a &struct pci_dev. If the earlier call
* to comedi_pci_enable() was successful, release the PCI device's regions
* and disable it. Reset @dev->ioenabled back to %false.
*/
void comedi_pci_disable(struct comedi_device *dev)
{
struct pci_dev *pcidev = comedi_to_pci_dev(dev);
if (pcidev && dev->ioenabled) {
pci_release_regions(pcidev);
pci_disable_device(pcidev);
}
dev->ioenabled = false;
}
EXPORT_SYMBOL_GPL(comedi_pci_disable);
/**
* comedi_pci_detach() - A generic "detach" handler for PCI COMEDI drivers
* @dev: COMEDI device.
*
* COMEDI drivers for PCI devices that need no special clean-up of private data
* and have no ioremapped regions other than that pointed to by @dev->mmio may
* use this function as its "detach" handler called by the COMEDI core when a
* COMEDI device is being detached from the low-level driver. It may be also
* called from a more specific "detach" handler that does additional clean-up.
*
* Free the IRQ if @dev->irq is non-zero, iounmap @dev->mmio if it is
* non-%NULL, and call comedi_pci_disable() to release the PCI device's regions
* and disable it.
*/
void comedi_pci_detach(struct comedi_device *dev)
{
struct pci_dev *pcidev = comedi_to_pci_dev(dev);
if (!pcidev || !dev->ioenabled)
return;
if (dev->irq) {
free_irq(dev->irq, dev);
dev->irq = 0;
}
if (dev->mmio) {
iounmap(dev->mmio);
dev->mmio = NULL;
}
comedi_pci_disable(dev);
}
EXPORT_SYMBOL_GPL(comedi_pci_detach);
/**
* comedi_pci_auto_config() - Configure/probe a PCI COMEDI device
* @pcidev: PCI device.
* @driver: Registered COMEDI driver.
* @context: Driver specific data, passed to comedi_auto_config().
*
* Typically called from the pci_driver (*probe) function. Auto-configure
* a COMEDI device, using the &struct device embedded in *@pcidev as the
* hardware device. The @context value gets passed through to @driver's
* "auto_attach" handler. The "auto_attach" handler may call
* comedi_to_pci_dev() on the passed in COMEDI device to recover @pcidev.
*
* Return: The result of calling comedi_auto_config() (0 on success, or
* a negative error number on failure).
*/
int comedi_pci_auto_config(struct pci_dev *pcidev,
struct comedi_driver *driver,
unsigned long context)
{
return comedi_auto_config(&pcidev->dev, driver, context);
}
EXPORT_SYMBOL_GPL(comedi_pci_auto_config);
/**
* comedi_pci_auto_unconfig() - Unconfigure/remove a PCI COMEDI device
* @pcidev: PCI device.
*
* Typically called from the pci_driver (*remove) function. Auto-unconfigure
* a COMEDI device attached to this PCI device, using a pointer to the
* &struct device embedded in *@pcidev as the hardware device. The COMEDI
* driver's "detach" handler will be called during unconfiguration of the
* COMEDI device.
*
* Note that the COMEDI device may have already been unconfigured using the
* %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it
* again should be ignored.
*/
void comedi_pci_auto_unconfig(struct pci_dev *pcidev)
{
comedi_auto_unconfig(&pcidev->dev);
}
EXPORT_SYMBOL_GPL(comedi_pci_auto_unconfig);
/**
* comedi_pci_driver_register() - Register a PCI COMEDI driver
* @comedi_driver: COMEDI driver to be registered.
* @pci_driver: PCI driver to be registered.
*
* This function is called from the module_init() of PCI COMEDI driver modules
* to register the COMEDI driver and the PCI driver. Do not call it directly,
* use the module_comedi_pci_driver() helper macro instead.
*
* Return: 0 on success, or a negative error number on failure.
*/
int comedi_pci_driver_register(struct comedi_driver *comedi_driver,
struct pci_driver *pci_driver)
{
int ret;
ret = comedi_driver_register(comedi_driver);
if (ret < 0)
return ret;
ret = pci_register_driver(pci_driver);
if (ret < 0) {
comedi_driver_unregister(comedi_driver);
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(comedi_pci_driver_register);
/**
* comedi_pci_driver_unregister() - Unregister a PCI COMEDI driver
* @comedi_driver: COMEDI driver to be unregistered.
* @pci_driver: PCI driver to be unregistered.
*
* This function is called from the module_exit() of PCI COMEDI driver modules
* to unregister the PCI driver and the COMEDI driver. Do not call it
* directly, use the module_comedi_pci_driver() helper macro instead.
*/
void comedi_pci_driver_unregister(struct comedi_driver *comedi_driver,
struct pci_driver *pci_driver)
{
pci_unregister_driver(pci_driver);
comedi_driver_unregister(comedi_driver);
}
EXPORT_SYMBOL_GPL(comedi_pci_driver_unregister);
static int __init comedi_pci_init(void)
{
return 0;
}
module_init(comedi_pci_init);
static void __exit comedi_pci_exit(void)
{
}
module_exit(comedi_pci_exit);
MODULE_AUTHOR("https://www.comedi.org");
MODULE_DESCRIPTION("Comedi PCI interface module");
MODULE_LICENSE("GPL");