1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * comedi_pcmcia.c
  4 * Comedi PCMCIA 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/kernel.h>
 12#include <linux/comedi/comedi_pcmcia.h>
 13
 14/**
 15 * comedi_to_pcmcia_dev() - Return PCMCIA 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 pcmcia_device.
 20 *
 21 * Return: Attached PCMCIA device if @dev->hw_dev is non-%NULL.
 22 * Return %NULL if @dev->hw_dev is %NULL.
 23 */
 24struct pcmcia_device *comedi_to_pcmcia_dev(struct comedi_device *dev)
 25{
 26	return dev->hw_dev ? to_pcmcia_dev(dev->hw_dev) : NULL;
 27}
 28EXPORT_SYMBOL_GPL(comedi_to_pcmcia_dev);
 29
 30static int comedi_pcmcia_conf_check(struct pcmcia_device *link,
 31				    void *priv_data)
 32{
 33	if (link->config_index == 0)
 34		return -EINVAL;
 35
 36	return pcmcia_request_io(link);
 37}
 38
 39/**
 40 * comedi_pcmcia_enable() - Request the regions and enable the PCMCIA device
 41 * @dev: COMEDI device.
 42 * @conf_check: Optional callback to check each configuration option of the
 43 *	PCMCIA device and request I/O regions.
 44 *
 45 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a a
 46 * &struct device embedded in a &struct pcmcia_device.  The comedi PCMCIA
 47 * driver needs to set the 'config_flags' member in the &struct pcmcia_device,
 48 * as appropriate for that driver, before calling this function in order to
 49 * allow pcmcia_loop_config() to do its internal autoconfiguration.
 50 *
 51 * If @conf_check is %NULL it is set to a default function.  If is
 52 * passed to pcmcia_loop_config() and should return %0 if the configuration
 53 * is valid and I/O regions requested successfully, otherwise it should return
 54 * a negative error value.  The default function returns -%EINVAL if the
 55 * 'config_index' member is %0, otherwise it calls pcmcia_request_io() and
 56 * returns the result.
 57 *
 58 * If the above configuration check passes, pcmcia_enable_device() is called
 59 * to set up and activate the PCMCIA device.
 60 *
 61 * If this function returns an error, comedi_pcmcia_disable() should be called
 62 * to release requested resources.
 63 *
 64 * Return:
 65 *	0 on success,
 66 *	-%ENODEV id @dev->hw_dev is %NULL,
 67 *	a negative error number from pcmcia_loop_config() if it fails,
 68 *	or a negative error number from pcmcia_enable_device() if it fails.
 69 */
 70int comedi_pcmcia_enable(struct comedi_device *dev,
 71			 int (*conf_check)(struct pcmcia_device *p_dev,
 72					   void *priv_data))
 73{
 74	struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
 75	int ret;
 76
 77	if (!link)
 78		return -ENODEV;
 79
 80	if (!conf_check)
 81		conf_check = comedi_pcmcia_conf_check;
 82
 83	ret = pcmcia_loop_config(link, conf_check, NULL);
 84	if (ret)
 85		return ret;
 86
 87	return pcmcia_enable_device(link);
 88}
 89EXPORT_SYMBOL_GPL(comedi_pcmcia_enable);
 90
 91/**
 92 * comedi_pcmcia_disable() - Disable the PCMCIA device and release the regions
 93 * @dev: COMEDI device.
 94 *
 95 * Assuming @dev->hw_dev is non-%NULL, it is assumed to be pointing to a
 96 * a &struct device embedded in a &struct pcmcia_device.  Call
 97 * pcmcia_disable_device() to disable and clean up the PCMCIA device.
 98 */
 99void comedi_pcmcia_disable(struct comedi_device *dev)
100{
101	struct pcmcia_device *link = comedi_to_pcmcia_dev(dev);
102
103	if (link)
104		pcmcia_disable_device(link);
105}
106EXPORT_SYMBOL_GPL(comedi_pcmcia_disable);
107
108/**
109 * comedi_pcmcia_auto_config() - Configure/probe a PCMCIA COMEDI device
110 * @link: PCMCIA device.
111 * @driver: Registered COMEDI driver.
112 *
113 * Typically called from the pcmcia_driver (*probe) function.  Auto-configure
114 * a COMEDI device, using a pointer to the &struct device embedded in *@link
115 * as the hardware device.  The @driver's "auto_attach" handler may call
116 * comedi_to_pcmcia_dev() on the passed in COMEDI device to recover @link.
117 *
118 * Return: The result of calling comedi_auto_config() (0 on success, or a
119 * negative error number on failure).
120 */
121int comedi_pcmcia_auto_config(struct pcmcia_device *link,
122			      struct comedi_driver *driver)
123{
124	return comedi_auto_config(&link->dev, driver, 0);
125}
126EXPORT_SYMBOL_GPL(comedi_pcmcia_auto_config);
127
128/**
129 * comedi_pcmcia_auto_unconfig() - Unconfigure/remove a PCMCIA COMEDI device
130 * @link: PCMCIA device.
131 *
132 * Typically called from the pcmcia_driver (*remove) function.
133 * Auto-unconfigure a COMEDI device attached to this PCMCIA device, using a
134 * pointer to the &struct device embedded in *@link as the hardware device.
135 * The COMEDI driver's "detach" handler will be called during unconfiguration
136 * of the COMEDI device.
137 *
138 * Note that the COMEDI device may have already been unconfigured using the
139 * %COMEDI_DEVCONFIG ioctl, in which case this attempt to unconfigure it
140 * again should be ignored.
141 */
142void comedi_pcmcia_auto_unconfig(struct pcmcia_device *link)
143{
144	comedi_auto_unconfig(&link->dev);
145}
146EXPORT_SYMBOL_GPL(comedi_pcmcia_auto_unconfig);
147
148/**
149 * comedi_pcmcia_driver_register() - Register a PCMCIA COMEDI driver
150 * @comedi_driver: COMEDI driver to be registered.
151 * @pcmcia_driver: PCMCIA driver to be registered.
152 *
153 * This function is used for the module_init() of PCMCIA COMEDI driver modules
154 * to register the COMEDI driver and the PCMCIA driver.  Do not call it
155 * directly, use the module_comedi_pcmcia_driver() helper macro instead.
156 *
157 * Return: 0 on success, or a negative error number on failure.
158 */
159int comedi_pcmcia_driver_register(struct comedi_driver *comedi_driver,
160				  struct pcmcia_driver *pcmcia_driver)
161{
162	int ret;
163
164	ret = comedi_driver_register(comedi_driver);
165	if (ret < 0)
166		return ret;
167
168	ret = pcmcia_register_driver(pcmcia_driver);
169	if (ret < 0) {
170		comedi_driver_unregister(comedi_driver);
171		return ret;
172	}
173
174	return 0;
175}
176EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_register);
177
178/**
179 * comedi_pcmcia_driver_unregister() - Unregister a PCMCIA COMEDI driver
180 * @comedi_driver: COMEDI driver to be registered.
181 * @pcmcia_driver: PCMCIA driver to be registered.
182 *
183 * This function is called from the module_exit() of PCMCIA COMEDI driver
184 * modules to unregister the PCMCIA driver and the COMEDI driver.  Do not call
185 * it directly, use the module_comedi_pcmcia_driver() helper macro instead.
186 */
187void comedi_pcmcia_driver_unregister(struct comedi_driver *comedi_driver,
188				     struct pcmcia_driver *pcmcia_driver)
189{
190	pcmcia_unregister_driver(pcmcia_driver);
191	comedi_driver_unregister(comedi_driver);
192}
193EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_unregister);
194
195static int __init comedi_pcmcia_init(void)
196{
197	return 0;
198}
199module_init(comedi_pcmcia_init);
200
201static void __exit comedi_pcmcia_exit(void)
202{
203}
204module_exit(comedi_pcmcia_exit);
205
206MODULE_AUTHOR("https://www.comedi.org");
207MODULE_DESCRIPTION("Comedi PCMCIA interface module");
208MODULE_LICENSE("GPL");