drivers/comedi/comedi_pcmcia.c

   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  */
  24 struct pcmcia_device *comedi_to_pcmcia_dev(struct comedi_device *dev)
  25 {
  26         return dev->hw_dev ? to_pcmcia_dev(dev->hw_dev) : NULL;
  27 }
  28 EXPORT_SYMBOL_GPL(comedi_to_pcmcia_dev);
  29
  30 static 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  */
  70 int 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 }
  89 EXPORT_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  */
  99 void 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 }
 106 EXPORT_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  */
 121 int comedi_pcmcia_auto_config(struct pcmcia_device *link,
 122                               struct comedi_driver *driver)
 123 {
 124         return comedi_auto_config(&link->dev, driver, 0);
 125 }
 126 EXPORT_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  */
 142 void comedi_pcmcia_auto_unconfig(struct pcmcia_device *link)
 143 {
 144         comedi_auto_unconfig(&link->dev);
 145 }
 146 EXPORT_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  */
 159 int 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 }
 176 EXPORT_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  */
 187 void 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 }
 193 EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_unregister);
 194
 195 static int __init comedi_pcmcia_init(void)
 196 {
 197         return 0;
 198 }
 199 module_init(comedi_pcmcia_init);
 200
 201 static void __exit comedi_pcmcia_exit(void)
 202 {
 203 }
 204 module_exit(comedi_pcmcia_exit);
 205
 206 MODULE_AUTHOR("https://www.comedi.org");
 207 MODULE_DESCRIPTION("Comedi PCMCIA interface module");
 208 MODULE_LICENSE("GPL");