linux/linux-5.18.11/drivers/comedi/comedi_pcmcia.c

209 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* comedi_pcmcia.c
* Comedi PCMCIA 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/kernel.h>
#include <linux/comedi/comedi_pcmcia.h>
/**
* comedi_to_pcmcia_dev() - Return PCMCIA 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 pcmcia_device.
*
* Return: Attached PCMCIA device if @dev->hw_dev is non-%NULL.
* Return %NULL if @dev->hw_dev is %NULL.
*/
struct pcmcia_device *comedi_to_pcmcia_dev(struct comedi_device *dev)
{
return dev->hw_dev ? to_pcmcia_dev(dev->hw_dev) : NULL;
}
EXPORT_SYMBOL_GPL(comedi_to_pcmcia_dev);
static int comedi_pcmcia_conf_check(struct pcmcia_device *link,
void *priv_data)
{
if (link->config_index == 0)
return -EINVAL;
return pcmcia_request_io(link);
}
/**
* comedi_pcmcia_enable() - Request the regions and enable the PCMCIA device
* @dev: COMEDI device.
* @conf_check: Optional callback to check each configuration option of the
* PCMCIA device and request I/O regions.
*
* Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a a
* &struct device embedded in a &struct pcmcia_device. The comedi PCMCIA
* driver needs to set the 'config_flags' member in the &struct pcmcia_device,
* as appropriate for that driver, before calling this function in order to
* allow pcmcia_loop_config() to do its internal autoconfiguration.
*
* If @conf_check is %NULL it is set to a default function. If is
* passed to pcmcia_loop_config() and should return %0 if the configuration
* is valid and I/O regions requested successfully, otherwise it should return
* a negative error value. The default function returns -%EINVAL if the
* 'config_index' member is %0, otherwise it calls pcmcia_request_io() and
* returns the result.
*
* If the above configuration check passes, pcmcia_enable_device() is called
* to set up and activate the PCMCIA device.
*
* If this function returns an error, comedi_pcmcia_disable() should be called
* to release requested resources.
*
* Return:
* 0 on success,
* -%ENODEV id @dev->hw_dev is %NULL,
* a negative error number from pcmcia_loop_config() if it fails,
* or a negative error number from pcmcia_enable_device() if it fails.
*/
int comedi_pcmcia_enable(struct comedi_device *dev,
int (*conf_check)(struct pcmcia_device *p_dev,
void *priv_data))
{
struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
int ret;
if (!link)
return -ENODEV;
if (!conf_check)
conf_check = comedi_pcmcia_conf_check;
ret = pcmcia_loop_config(link, conf_check, NULL);
if (ret)
return ret;
return pcmcia_enable_device(link);
}
EXPORT_SYMBOL_GPL(comedi_pcmcia_enable);
/**
* comedi_pcmcia_disable() - Disable the PCMCIA device and release 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 pcmcia_device. Call
* pcmcia_disable_device() to disable and clean up the PCMCIA device.
*/
void comedi_pcmcia_disable(struct comedi_device *dev)
{
struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
if (link)
pcmcia_disable_device(link);
}
EXPORT_SYMBOL_GPL(comedi_pcmcia_disable);
/**
* comedi_pcmcia_auto_config() - Configure/probe a PCMCIA COMEDI device
* @link: PCMCIA device.
* @driver: Registered COMEDI driver.
*
* Typically called from the pcmcia_driver (*probe) function. Auto-configure
* a COMEDI device, using a pointer to the &struct device embedded in *@link
* as the hardware device. The @driver's "auto_attach" handler may call
* comedi_to_pcmcia_dev() on the passed in COMEDI device to recover @link.
*
* Return: The result of calling comedi_auto_config() (0 on success, or a
* negative error number on failure).
*/
int comedi_pcmcia_auto_config(struct pcmcia_device *link,
struct comedi_driver *driver)
{
return comedi_auto_config(&link->dev, driver, 0);
}
EXPORT_SYMBOL_GPL(comedi_pcmcia_auto_config);
/**
* comedi_pcmcia_auto_unconfig() - Unconfigure/remove a PCMCIA COMEDI device
* @link: PCMCIA device.
*
* Typically called from the pcmcia_driver (*remove) function.
* Auto-unconfigure a COMEDI device attached to this PCMCIA device, using a
* pointer to the &struct device embedded in *@link 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_pcmcia_auto_unconfig(struct pcmcia_device *link)
{
comedi_auto_unconfig(&link->dev);
}
EXPORT_SYMBOL_GPL(comedi_pcmcia_auto_unconfig);
/**
* comedi_pcmcia_driver_register() - Register a PCMCIA COMEDI driver
* @comedi_driver: COMEDI driver to be registered.
* @pcmcia_driver: PCMCIA driver to be registered.
*
* This function is used for the module_init() of PCMCIA COMEDI driver modules
* to register the COMEDI driver and the PCMCIA driver. Do not call it
* directly, use the module_comedi_pcmcia_driver() helper macro instead.
*
* Return: 0 on success, or a negative error number on failure.
*/
int comedi_pcmcia_driver_register(struct comedi_driver *comedi_driver,
struct pcmcia_driver *pcmcia_driver)
{
int ret;
ret = comedi_driver_register(comedi_driver);
if (ret < 0)
return ret;
ret = pcmcia_register_driver(pcmcia_driver);
if (ret < 0) {
comedi_driver_unregister(comedi_driver);
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_register);
/**
* comedi_pcmcia_driver_unregister() - Unregister a PCMCIA COMEDI driver
* @comedi_driver: COMEDI driver to be registered.
* @pcmcia_driver: PCMCIA driver to be registered.
*
* This function is called from the module_exit() of PCMCIA COMEDI driver
* modules to unregister the PCMCIA driver and the COMEDI driver. Do not call
* it directly, use the module_comedi_pcmcia_driver() helper macro instead.
*/
void comedi_pcmcia_driver_unregister(struct comedi_driver *comedi_driver,
struct pcmcia_driver *pcmcia_driver)
{
pcmcia_unregister_driver(pcmcia_driver);
comedi_driver_unregister(comedi_driver);
}
EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_unregister);
static int __init comedi_pcmcia_init(void)
{
return 0;
}
module_init(comedi_pcmcia_init);
static void __exit comedi_pcmcia_exit(void)
{
}
module_exit(comedi_pcmcia_exit);
MODULE_AUTHOR("https://www.comedi.org");
MODULE_DESCRIPTION("Comedi PCMCIA interface module");
MODULE_LICENSE("GPL");