From 127a0cf9b091fe85b6624a4ac8164d6b2cf76143 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Wed, 30 Sep 2015 17:10:57 +0100 Subject: [PATCH] staging: comedi: comedi_pcmcia.c: improve function documentation Expand the descriptions of the functions and document the return values. Signed-off-by: Ian Abbott Reviewed-by: H Hartley Sweeten Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/comedi_pcmcia.c | 104 ++++++++++++++++++------- 1 file changed, 76 insertions(+), 28 deletions(-) diff --git a/drivers/staging/comedi/comedi_pcmcia.c b/drivers/staging/comedi/comedi_pcmcia.c index 7e784399a16f..d7072a5c1647 100644 --- a/drivers/staging/comedi/comedi_pcmcia.c +++ b/drivers/staging/comedi/comedi_pcmcia.c @@ -22,8 +22,14 @@ #include "comedi_pcmcia.h" /** - * comedi_to_pcmcia_dev() - comedi_device pointer to pcmcia_device pointer. - * @dev: comedi_device struct + * 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) { @@ -41,13 +47,35 @@ static int comedi_pcmcia_conf_check(struct pcmcia_device *link, } /** - * comedi_pcmcia_enable() - Request the regions and enable the PCMCIA device. - * @dev: comedi_device struct - * @conf_check: optional callback to check the pcmcia_device configuration + * 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. * - * The comedi PCMCIA driver needs to set the link->config_flags, as - * appropriate for that driver, before calling this function in order - * to allow pcmcia_loop_config() to do its internal autoconfiguration. + * 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 *, void *)) @@ -70,8 +98,12 @@ int comedi_pcmcia_enable(struct comedi_device *dev, EXPORT_SYMBOL_GPL(comedi_pcmcia_enable); /** - * comedi_pcmcia_disable() - Disable the PCMCIA device and release the regions. - * @dev: comedi_device struct + * 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) { @@ -83,11 +115,17 @@ void comedi_pcmcia_disable(struct comedi_device *dev) EXPORT_SYMBOL_GPL(comedi_pcmcia_disable); /** - * comedi_pcmcia_auto_config() - Configure/probe a comedi PCMCIA driver. - * @link: pcmcia_device struct - * @driver: comedi_driver struct + * 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. * - * Typically called from the pcmcia_driver (*probe) function. + * 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) @@ -97,10 +135,18 @@ int comedi_pcmcia_auto_config(struct pcmcia_device *link, EXPORT_SYMBOL_GPL(comedi_pcmcia_auto_config); /** - * comedi_pcmcia_auto_unconfig() - Unconfigure/remove a comedi PCMCIA driver. - * @link: pcmcia_device struct + * 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) { @@ -109,13 +155,15 @@ void comedi_pcmcia_auto_unconfig(struct pcmcia_device *link) EXPORT_SYMBOL_GPL(comedi_pcmcia_auto_unconfig); /** - * comedi_pcmcia_driver_register() - Register a comedi PCMCIA driver. - * @comedi_driver: comedi_driver struct - * @pcmcia_driver: pcmcia_driver struct + * 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. * - * This function is used for the module_init() of comedi USB drivers. - * 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) @@ -137,13 +185,13 @@ int comedi_pcmcia_driver_register(struct comedi_driver *comedi_driver, EXPORT_SYMBOL_GPL(comedi_pcmcia_driver_register); /** - * comedi_pcmcia_driver_unregister() - Unregister a comedi PCMCIA driver. - * @comedi_driver: comedi_driver struct - * @pcmcia_driver: pcmcia_driver struct + * 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 used for the module_exit() of comedi PCMCIA drivers. - * Do not call it directly, use the module_comedi_pcmcia_driver() helper - * macro instead. + * 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) -- 2.39.2