/* SPDX-License-Identifier: GPL-2.0+ */ /* * comedidev.h * header file for kernel-only structures, variables, and constants * * COMEDI - Linux Control and Measurement Device Interface * Copyright (C) 1997-2000 David A. Schleef <[email protected]> */ #ifndef _COMEDIDEV_H #define _COMEDIDEV_H #include <linux/dma-mapping.h> #include <linux/mutex.h> #include <linux/spinlock_types.h> #include <linux/rwsem.h> #include <linux/kref.h> #include <linux/comedi.h> #define COMEDI_VERSION(a, b, c) … #define COMEDI_VERSION_CODE … #define COMEDI_RELEASE … #define COMEDI_NUM_BOARD_MINORS … /** * struct comedi_subdevice - Working data for a COMEDI subdevice * @device: COMEDI device to which this subdevice belongs. (Initialized by * comedi_alloc_subdevices().) * @index: Index of this subdevice within device's array of subdevices. * (Initialized by comedi_alloc_subdevices().) * @type: Type of subdevice from &enum comedi_subdevice_type. (Initialized by * the low-level driver.) * @n_chan: Number of channels the subdevice supports. (Initialized by the * low-level driver.) * @subdev_flags: Various "SDF" flags indicating aspects of the subdevice to * the COMEDI core and user application. (Initialized by the low-level * driver.) * @len_chanlist: Maximum length of a channel list if the subdevice supports * asynchronous acquisition commands. (Optionally initialized by the * low-level driver, or changed from 0 to 1 during post-configuration.) * @private: Private data pointer which is either set by the low-level driver * itself, or by a call to comedi_alloc_spriv() which allocates storage. * In the latter case, the storage is automatically freed after the * low-level driver's "detach" handler is called for the device. * (Initialized by the low-level driver.) * @async: Pointer to &struct comedi_async id the subdevice supports * asynchronous acquisition commands. (Allocated and initialized during * post-configuration if needed.) * @lock: Pointer to a file object that performed a %COMEDI_LOCK ioctl on the * subdevice. (Initially NULL.) * @busy: Pointer to a file object that is performing an asynchronous * acquisition command on the subdevice. (Initially NULL.) * @runflags: Internal flags for use by COMEDI core, mostly indicating whether * an asynchronous acquisition command is running. * @spin_lock: Generic spin-lock for use by the COMEDI core and the low-level * driver. (Initialized by comedi_alloc_subdevices().) * @io_bits: Bit-mask indicating the channel directions for a DIO subdevice * with no more than 32 channels. A '1' at a bit position indicates the * corresponding channel is configured as an output. (Initialized by the * low-level driver for a DIO subdevice. Forced to all-outputs during * post-configuration for a digital output subdevice.) * @maxdata: If non-zero, this is the maximum raw data value of each channel. * If zero, the maximum data value is channel-specific. (Initialized by * the low-level driver.) * @maxdata_list: If the maximum data value is channel-specific, this points * to an array of maximum data values indexed by channel index. * (Initialized by the low-level driver.) * @range_table: If non-NULL, this points to a COMEDI range table for the * subdevice. If NULL, the range table is channel-specific. (Initialized * by the low-level driver, will be set to an "invalid" range table during * post-configuration if @range_table and @range_table_list are both * NULL.) * @range_table_list: If the COMEDI range table is channel-specific, this * points to an array of pointers to COMEDI range tables indexed by * channel number. (Initialized by the low-level driver.) * @chanlist: Not used. * @insn_read: Optional pointer to a handler for the %INSN_READ instruction. * (Initialized by the low-level driver, or set to a default handler * during post-configuration.) * @insn_write: Optional pointer to a handler for the %INSN_WRITE instruction. * (Initialized by the low-level driver, or set to a default handler * during post-configuration.) * @insn_bits: Optional pointer to a handler for the %INSN_BITS instruction * for a digital input, digital output or digital input/output subdevice. * (Initialized by the low-level driver, or set to a default handler * during post-configuration.) * @insn_config: Optional pointer to a handler for the %INSN_CONFIG * instruction. (Initialized by the low-level driver, or set to a default * handler during post-configuration.) * @do_cmd: If the subdevice supports asynchronous acquisition commands, this * points to a handler to set it up in hardware. (Initialized by the * low-level driver.) * @do_cmdtest: If the subdevice supports asynchronous acquisition commands, * this points to a handler used to check and possibly tweak a prospective * acquisition command without setting it up in hardware. (Initialized by * the low-level driver.) * @poll: If the subdevice supports asynchronous acquisition commands, this * is an optional pointer to a handler for the %COMEDI_POLL ioctl which * instructs the low-level driver to synchronize buffers. (Initialized by * the low-level driver if needed.) * @cancel: If the subdevice supports asynchronous acquisition commands, this * points to a handler used to terminate a running command. (Initialized * by the low-level driver.) * @buf_change: If the subdevice supports asynchronous acquisition commands, * this is an optional pointer to a handler that is called when the data * buffer for handling asynchronous commands is allocated or reallocated. * (Initialized by the low-level driver if needed.) * @munge: If the subdevice supports asynchronous acquisition commands and * uses DMA to transfer data from the hardware to the acquisition buffer, * this points to a function used to "munge" the data values from the * hardware into the format expected by COMEDI. (Initialized by the * low-level driver if needed.) * @async_dma_dir: If the subdevice supports asynchronous acquisition commands * and uses DMA to transfer data from the hardware to the acquisition * buffer, this sets the DMA direction for the buffer. (initialized to * %DMA_NONE by comedi_alloc_subdevices() and changed by the low-level * driver if necessary.) * @state: Handy bit-mask indicating the output states for a DIO or digital * output subdevice with no more than 32 channels. (Initialized by the * low-level driver.) * @class_dev: If the subdevice supports asynchronous acquisition commands, * this points to a sysfs comediX_subdY device where X is the minor device * number of the COMEDI device and Y is the subdevice number. The minor * device number for the sysfs device is allocated dynamically in the * range 48 to 255. This is used to allow the COMEDI device to be opened * with a different default read or write subdevice. (Allocated during * post-configuration if needed.) * @minor: If @class_dev is set, this is its dynamically allocated minor * device number. (Set during post-configuration if necessary.) * @readback: Optional pointer to memory allocated by * comedi_alloc_subdev_readback() used to hold the values written to * analog output channels so they can be read back. The storage is * automatically freed after the low-level driver's "detach" handler is * called for the device. (Initialized by the low-level driver.) * * This is the main control structure for a COMEDI subdevice. If the subdevice * supports asynchronous acquisition commands, additional information is stored * in the &struct comedi_async pointed to by @async. * * Most of the subdevice is initialized by the low-level driver's "attach" or * "auto_attach" handlers but parts of it are initialized by * comedi_alloc_subdevices(), and other parts are initialized during * post-configuration on return from that handler. * * A low-level driver that sets @insn_bits for a digital input, digital output, * or DIO subdevice may leave @insn_read and @insn_write uninitialized, in * which case they will be set to a default handler during post-configuration * that uses @insn_bits to emulate the %INSN_READ and %INSN_WRITE instructions. */ struct comedi_subdevice { … }; /** * struct comedi_buf_page - Describe a page of a COMEDI buffer * @virt_addr: Kernel address of page. * @dma_addr: DMA address of page if in DMA coherent memory. */ struct comedi_buf_page { … }; /** * struct comedi_buf_map - Describe pages in a COMEDI buffer * @dma_hw_dev: Low-level hardware &struct device pointer copied from the * COMEDI device's hw_dev member. * @page_list: Pointer to array of &struct comedi_buf_page, one for each * page in the buffer. * @n_pages: Number of pages in the buffer. * @dma_dir: DMA direction used to allocate pages of DMA coherent memory, * or %DMA_NONE if pages allocated from regular memory. * @refcount: &struct kref reference counter used to free the buffer. * * A COMEDI data buffer is allocated as individual pages, either in * conventional memory or DMA coherent memory, depending on the attached, * low-level hardware device. (The buffer pages also get mapped into the * kernel's contiguous virtual address space pointed to by the 'prealloc_buf' * member of &struct comedi_async.) * * The buffer is normally freed when the COMEDI device is detached from the * low-level driver (which may happen due to device removal), but if it happens * to be mmapped at the time, the pages cannot be freed until the buffer has * been munmapped. That is what the reference counter is for. (The virtual * address space pointed by 'prealloc_buf' is freed when the COMEDI device is * detached.) */ struct comedi_buf_map { … }; /** * struct comedi_async - Control data for asynchronous COMEDI commands * @prealloc_buf: Kernel virtual address of allocated acquisition buffer. * @prealloc_bufsz: Buffer size (in bytes). * @buf_map: Map of buffer pages. * @max_bufsize: Maximum allowed buffer size (in bytes). * @buf_write_count: "Write completed" count (in bytes, modulo 2**32). * @buf_write_alloc_count: "Allocated for writing" count (in bytes, * modulo 2**32). * @buf_read_count: "Read completed" count (in bytes, modulo 2**32). * @buf_read_alloc_count: "Allocated for reading" count (in bytes, * modulo 2**32). * @buf_write_ptr: Buffer position for writer. * @buf_read_ptr: Buffer position for reader. * @cur_chan: Current position in chanlist for scan (for those drivers that * use it). * @scans_done: The number of scans completed. * @scan_progress: Amount received or sent for current scan (in bytes). * @munge_chan: Current position in chanlist for "munging". * @munge_count: "Munge" count (in bytes, modulo 2**32). * @munge_ptr: Buffer position for "munging". * @events: Bit-vector of events that have occurred. * @cmd: Details of comedi command in progress. * @wait_head: Task wait queue for file reader or writer. * @cb_mask: Bit-vector of events that should wake waiting tasks. * @inttrig: Software trigger function for command, or NULL. * * Note about the ..._count and ..._ptr members: * * Think of the _Count values being integers of unlimited size, indexing * into a buffer of infinite length (though only an advancing portion * of the buffer of fixed length prealloc_bufsz is accessible at any * time). Then: * * Buf_Read_Count <= Buf_Read_Alloc_Count <= Munge_Count <= * Buf_Write_Count <= Buf_Write_Alloc_Count <= * (Buf_Read_Count + prealloc_bufsz) * * (Those aren't the actual members, apart from prealloc_bufsz.) When the * buffer is reset, those _Count values start at 0 and only increase in value, * maintaining the above inequalities until the next time the buffer is * reset. The buffer is divided into the following regions by the inequalities: * * [0, Buf_Read_Count): * old region no longer accessible * * [Buf_Read_Count, Buf_Read_Alloc_Count): * filled and munged region allocated for reading but not yet read * * [Buf_Read_Alloc_Count, Munge_Count): * filled and munged region not yet allocated for reading * * [Munge_Count, Buf_Write_Count): * filled region not yet munged * * [Buf_Write_Count, Buf_Write_Alloc_Count): * unfilled region allocated for writing but not yet written * * [Buf_Write_Alloc_Count, Buf_Read_Count + prealloc_bufsz): * unfilled region not yet allocated for writing * * [Buf_Read_Count + prealloc_bufsz, infinity): * unfilled region not yet accessible * * Data needs to be written into the buffer before it can be read out, * and may need to be converted (or "munged") between the two * operations. Extra unfilled buffer space may need to allocated for * writing (advancing Buf_Write_Alloc_Count) before new data is written. * After writing new data, the newly filled space needs to be released * (advancing Buf_Write_Count). This also results in the new data being * "munged" (advancing Munge_Count). Before data is read out of the * buffer, extra space may need to be allocated for reading (advancing * Buf_Read_Alloc_Count). After the data has been read out, the space * needs to be released (advancing Buf_Read_Count). * * The actual members, buf_read_count, buf_read_alloc_count, * munge_count, buf_write_count, and buf_write_alloc_count take the * value of the corresponding capitalized _Count values modulo 2^32 * (UINT_MAX+1). Subtracting a "higher" _count value from a "lower" * _count value gives the same answer as subtracting a "higher" _Count * value from a lower _Count value because prealloc_bufsz < UINT_MAX+1. * The modulo operation is done implicitly. * * The buf_read_ptr, munge_ptr, and buf_write_ptr members take the value * of the corresponding capitalized _Count values modulo prealloc_bufsz. * These correspond to byte indices in the physical buffer. The modulo * operation is done by subtracting prealloc_bufsz when the value * exceeds prealloc_bufsz (assuming prealloc_bufsz plus the increment is * less than or equal to UINT_MAX). */ struct comedi_async { … }; /** * enum comedi_cb - &struct comedi_async callback "events" * @COMEDI_CB_EOS: end-of-scan * @COMEDI_CB_EOA: end-of-acquisition/output * @COMEDI_CB_BLOCK: data has arrived, wakes up read() / write() * @COMEDI_CB_EOBUF: DEPRECATED: end of buffer * @COMEDI_CB_ERROR: card error during acquisition * @COMEDI_CB_OVERFLOW: buffer overflow/underflow * @COMEDI_CB_ERROR_MASK: events that indicate an error has occurred * @COMEDI_CB_CANCEL_MASK: events that will cancel an async command */ enum comedi_cb { … }; /** * struct comedi_driver - COMEDI driver registration * @driver_name: Name of driver. * @module: Owning module. * @attach: The optional "attach" handler for manually configured COMEDI * devices. * @detach: The "detach" handler for deconfiguring COMEDI devices. * @auto_attach: The optional "auto_attach" handler for automatically * configured COMEDI devices. * @num_names: Optional number of "board names" supported. * @board_name: Optional pointer to a pointer to a board name. The pointer * to a board name is embedded in an element of a driver-defined array * of static, read-only board type information. * @offset: Optional size of each element of the driver-defined array of * static, read-only board type information, i.e. the offset between each * pointer to a board name. * * This is used with comedi_driver_register() and comedi_driver_unregister() to * register and unregister a low-level COMEDI driver with the COMEDI core. * * If @num_names is non-zero, @board_name should be non-NULL, and @offset * should be at least sizeof(*board_name). These are used by the handler for * the %COMEDI_DEVCONFIG ioctl to match a hardware device and its driver by * board name. If @num_names is zero, the %COMEDI_DEVCONFIG ioctl matches a * hardware device and its driver by driver name. This is only useful if the * @attach handler is set. If @num_names is non-zero, the driver's @attach * handler will be called with the COMEDI device structure's board_ptr member * pointing to the matched pointer to a board name within the driver's private * array of static, read-only board type information. * * The @detach handler has two roles. If a COMEDI device was successfully * configured by the @attach or @auto_attach handler, it is called when the * device is being deconfigured (by the %COMEDI_DEVCONFIG ioctl, or due to * unloading of the driver, or due to device removal). It is also called when * the @attach or @auto_attach handler returns an error. Therefore, the * @attach or @auto_attach handlers can defer clean-up on error until the * @detach handler is called. If the @attach or @auto_attach handlers free * any resources themselves, they must prevent the @detach handler from * freeing the same resources. The @detach handler must not assume that all * resources requested by the @attach or @auto_attach handler were * successfully allocated. */ struct comedi_driver { … }; /** * struct comedi_device - Working data for a COMEDI device * @use_count: Number of open file objects. * @driver: Low-level COMEDI driver attached to this COMEDI device. * @pacer: Optional pointer to a dynamically allocated acquisition pacer * control. It is freed automatically after the COMEDI device is * detached from the low-level driver. * @private: Optional pointer to private data allocated by the low-level * driver. It is freed automatically after the COMEDI device is * detached from the low-level driver. * @class_dev: Sysfs comediX device. * @minor: Minor device number of COMEDI char device (0-47). * @detach_count: Counter incremented every time the COMEDI device is detached. * Used for checking a previous attachment is still valid. * @hw_dev: Optional pointer to the low-level hardware &struct device. It is * required for automatically configured COMEDI devices and optional for * COMEDI devices configured by the %COMEDI_DEVCONFIG ioctl, although * the bus-specific COMEDI functions only work if it is set correctly. * It is also passed to dma_alloc_coherent() for COMEDI subdevices that * have their 'async_dma_dir' member set to something other than * %DMA_NONE. * @board_name: Pointer to a COMEDI board name or a COMEDI driver name. When * the low-level driver's "attach" handler is called by the handler for * the %COMEDI_DEVCONFIG ioctl, it either points to a matched board name * string if the 'num_names' member of the &struct comedi_driver is * non-zero, otherwise it points to the low-level driver name string. * When the low-lever driver's "auto_attach" handler is called for an * automatically configured COMEDI device, it points to the low-level * driver name string. The low-level driver is free to change it in its * "attach" or "auto_attach" handler if it wishes. * @board_ptr: Optional pointer to private, read-only board type information in * the low-level driver. If the 'num_names' member of the &struct * comedi_driver is non-zero, the handler for the %COMEDI_DEVCONFIG ioctl * will point it to a pointer to a matched board name string within the * driver's private array of static, read-only board type information when * calling the driver's "attach" handler. The low-level driver is free to * change it. * @attached: Flag indicating that the COMEDI device is attached to a low-level * driver. * @ioenabled: Flag used to indicate that a PCI device has been enabled and * its regions requested. * @spinlock: Generic spin-lock for use by the low-level driver. * @mutex: Generic mutex for use by the COMEDI core module. * @attach_lock: &struct rw_semaphore used to guard against the COMEDI device * being detached while an operation is in progress. The down_write() * operation is only allowed while @mutex is held and is used when * changing @attached and @detach_count and calling the low-level driver's * "detach" handler. The down_read() operation is generally used without * holding @mutex. * @refcount: &struct kref reference counter for freeing COMEDI device. * @n_subdevices: Number of COMEDI subdevices allocated by the low-level * driver for this device. * @subdevices: Dynamically allocated array of COMEDI subdevices. * @mmio: Optional pointer to a remapped MMIO region set by the low-level * driver. * @iobase: Optional base of an I/O port region requested by the low-level * driver. * @iolen: Length of I/O port region requested at @iobase. * @irq: Optional IRQ number requested by the low-level driver. * @read_subdev: Optional pointer to a default COMEDI subdevice operated on by * the read() file operation. Set by the low-level driver. * @write_subdev: Optional pointer to a default COMEDI subdevice operated on by * the write() file operation. Set by the low-level driver. * @async_queue: Storage for fasync_helper(). * @open: Optional pointer to a function set by the low-level driver to be * called when @use_count changes from 0 to 1. * @close: Optional pointer to a function set by the low-level driver to be * called when @use_count changed from 1 to 0. * @insn_device_config: Optional pointer to a handler for all sub-instructions * except %INSN_DEVICE_CONFIG_GET_ROUTES of the %INSN_DEVICE_CONFIG * instruction. If this is not initialized by the low-level driver, a * default handler will be set during post-configuration. * @get_valid_routes: Optional pointer to a handler for the * %INSN_DEVICE_CONFIG_GET_ROUTES sub-instruction of the * %INSN_DEVICE_CONFIG instruction set. If this is not initialized by the * low-level driver, a default handler that copies zero routes back to the * user will be used. * * This is the main control data structure for a COMEDI device (as far as the * COMEDI core is concerned). There are two groups of COMEDI devices - * "legacy" devices that are configured by the handler for the * %COMEDI_DEVCONFIG ioctl, and automatically configured devices resulting * from a call to comedi_auto_config() as a result of a bus driver probe in * a low-level COMEDI driver. The "legacy" COMEDI devices are allocated * during module initialization if the "comedi_num_legacy_minors" module * parameter is non-zero and use minor device numbers from 0 to * comedi_num_legacy_minors minus one. The automatically configured COMEDI * devices are allocated on demand and use minor device numbers from * comedi_num_legacy_minors to 47. */ struct comedi_device { … }; /* * function prototypes */ void comedi_event(struct comedi_device *dev, struct comedi_subdevice *s); struct comedi_device *comedi_dev_get_from_minor(unsigned int minor); int comedi_dev_put(struct comedi_device *dev); bool comedi_is_subdevice_running(struct comedi_subdevice *s); void *comedi_alloc_spriv(struct comedi_subdevice *s, size_t size); void comedi_set_spriv_auto_free(struct comedi_subdevice *s); int comedi_check_chanlist(struct comedi_subdevice *s, int n, unsigned int *chanlist); /* range stuff */ #define RANGE(a, b) … #define RANGE_ext(a, b) … #define RANGE_mA(a, b) … #define RANGE_unitless(a, b) … #define BIP_RANGE(a) … #define UNI_RANGE(a) … extern const struct comedi_lrange range_bipolar10; extern const struct comedi_lrange range_bipolar5; extern const struct comedi_lrange range_bipolar2_5; extern const struct comedi_lrange range_unipolar10; extern const struct comedi_lrange range_unipolar5; extern const struct comedi_lrange range_unipolar2_5; extern const struct comedi_lrange range_0_20mA; extern const struct comedi_lrange range_4_20mA; extern const struct comedi_lrange range_0_32mA; extern const struct comedi_lrange range_unknown; #define range_digital … /** * struct comedi_lrange - Describes a COMEDI range table * @length: Number of entries in the range table. * @range: Array of &struct comedi_krange, one for each range. * * Each element of @range[] describes the minimum and maximum physical range * and the type of units. Typically, the type of unit is %UNIT_volt * (i.e. volts) and the minimum and maximum are in millionths of a volt. * There may also be a flag that indicates the minimum and maximum are merely * scale factors for an unknown, external reference. */ struct comedi_lrange { … }; /** * comedi_range_is_bipolar() - Test if subdevice range is bipolar * @s: COMEDI subdevice. * @range: Index of range within a range table. * * Tests whether a range is bipolar by checking whether its minimum value * is negative. * * Assumes @range is valid. Does not work for subdevices using a * channel-specific range table list. * * Return: * %true if the range is bipolar. * %false if the range is unipolar. */ static inline bool comedi_range_is_bipolar(struct comedi_subdevice *s, unsigned int range) { … } /** * comedi_range_is_unipolar() - Test if subdevice range is unipolar * @s: COMEDI subdevice. * @range: Index of range within a range table. * * Tests whether a range is unipolar by checking whether its minimum value * is at least 0. * * Assumes @range is valid. Does not work for subdevices using a * channel-specific range table list. * * Return: * %true if the range is unipolar. * %false if the range is bipolar. */ static inline bool comedi_range_is_unipolar(struct comedi_subdevice *s, unsigned int range) { … } /** * comedi_range_is_external() - Test if subdevice range is external * @s: COMEDI subdevice. * @range: Index of range within a range table. * * Tests whether a range is externally reference by checking whether its * %RF_EXTERNAL flag is set. * * Assumes @range is valid. Does not work for subdevices using a * channel-specific range table list. * * Return: * %true if the range is external. * %false if the range is internal. */ static inline bool comedi_range_is_external(struct comedi_subdevice *s, unsigned int range) { … } /** * comedi_chan_range_is_bipolar() - Test if channel-specific range is bipolar * @s: COMEDI subdevice. * @chan: The channel number. * @range: Index of range within a range table. * * Tests whether a range is bipolar by checking whether its minimum value * is negative. * * Assumes @chan and @range are valid. Only works for subdevices with a * channel-specific range table list. * * Return: * %true if the range is bipolar. * %false if the range is unipolar. */ static inline bool comedi_chan_range_is_bipolar(struct comedi_subdevice *s, unsigned int chan, unsigned int range) { … } /** * comedi_chan_range_is_unipolar() - Test if channel-specific range is unipolar * @s: COMEDI subdevice. * @chan: The channel number. * @range: Index of range within a range table. * * Tests whether a range is unipolar by checking whether its minimum value * is at least 0. * * Assumes @chan and @range are valid. Only works for subdevices with a * channel-specific range table list. * * Return: * %true if the range is unipolar. * %false if the range is bipolar. */ static inline bool comedi_chan_range_is_unipolar(struct comedi_subdevice *s, unsigned int chan, unsigned int range) { … } /** * comedi_chan_range_is_external() - Test if channel-specific range is external * @s: COMEDI subdevice. * @chan: The channel number. * @range: Index of range within a range table. * * Tests whether a range is externally reference by checking whether its * %RF_EXTERNAL flag is set. * * Assumes @chan and @range are valid. Only works for subdevices with a * channel-specific range table list. * * Return: * %true if the range is bipolar. * %false if the range is unipolar. */ static inline bool comedi_chan_range_is_external(struct comedi_subdevice *s, unsigned int chan, unsigned int range) { … } /** * comedi_offset_munge() - Convert between offset binary and 2's complement * @s: COMEDI subdevice. * @val: Value to be converted. * * Toggles the highest bit of a sample value to toggle between offset binary * and 2's complement. Assumes that @s->maxdata is a power of 2 minus 1. * * Return: The converted value. */ static inline unsigned int comedi_offset_munge(struct comedi_subdevice *s, unsigned int val) { … } /** * comedi_bytes_per_sample() - Determine subdevice sample size * @s: COMEDI subdevice. * * The sample size will be 4 (sizeof int) or 2 (sizeof short) depending on * whether the %SDF_LSAMPL subdevice flag is set or not. * * Return: The subdevice sample size. */ static inline unsigned int comedi_bytes_per_sample(struct comedi_subdevice *s) { … } /** * comedi_sample_shift() - Determine log2 of subdevice sample size * @s: COMEDI subdevice. * * The sample size will be 4 (sizeof int) or 2 (sizeof short) depending on * whether the %SDF_LSAMPL subdevice flag is set or not. The log2 of the * sample size will be 2 or 1 and can be used as the right operand of a * bit-shift operator to multiply or divide something by the sample size. * * Return: log2 of the subdevice sample size. */ static inline unsigned int comedi_sample_shift(struct comedi_subdevice *s) { … } /** * comedi_bytes_to_samples() - Convert a number of bytes to a number of samples * @s: COMEDI subdevice. * @nbytes: Number of bytes * * Return: The number of bytes divided by the subdevice sample size. */ static inline unsigned int comedi_bytes_to_samples(struct comedi_subdevice *s, unsigned int nbytes) { … } /** * comedi_samples_to_bytes() - Convert a number of samples to a number of bytes * @s: COMEDI subdevice. * @nsamples: Number of samples. * * Return: The number of samples multiplied by the subdevice sample size. * (Does not check for arithmetic overflow.) */ static inline unsigned int comedi_samples_to_bytes(struct comedi_subdevice *s, unsigned int nsamples) { … } /** * comedi_check_trigger_src() - Trivially validate a comedi_cmd trigger source * @src: Pointer to the trigger source to validate. * @flags: Bitmask of valid %TRIG_* for the trigger. * * This is used in "step 1" of the do_cmdtest functions of comedi drivers * to validate the comedi_cmd triggers. The mask of the @src against the * @flags allows the userspace comedilib to pass all the comedi_cmd * triggers as %TRIG_ANY and get back a bitmask of the valid trigger sources. * * Return: * 0 if trigger sources in *@src are all supported. * -EINVAL if any trigger source in *@src is unsupported. */ static inline int comedi_check_trigger_src(unsigned int *src, unsigned int flags) { … } /** * comedi_check_trigger_is_unique() - Make sure a trigger source is unique * @src: The trigger source to check. * * Return: * 0 if no more than one trigger source is set. * -EINVAL if more than one trigger source is set. */ static inline int comedi_check_trigger_is_unique(unsigned int src) { … } /** * comedi_check_trigger_arg_is() - Trivially validate a trigger argument * @arg: Pointer to the trigger arg to validate. * @val: The value the argument should be. * * Forces *@arg to be @val. * * Return: * 0 if *@arg was already @val. * -EINVAL if *@arg differed from @val. */ static inline int comedi_check_trigger_arg_is(unsigned int *arg, unsigned int val) { … } /** * comedi_check_trigger_arg_min() - Trivially validate a trigger argument min * @arg: Pointer to the trigger arg to validate. * @val: The minimum value the argument should be. * * Forces *@arg to be at least @val, setting it to @val if necessary. * * Return: * 0 if *@arg was already at least @val. * -EINVAL if *@arg was less than @val. */ static inline int comedi_check_trigger_arg_min(unsigned int *arg, unsigned int val) { … } /** * comedi_check_trigger_arg_max() - Trivially validate a trigger argument max * @arg: Pointer to the trigger arg to validate. * @val: The maximum value the argument should be. * * Forces *@arg to be no more than @val, setting it to @val if necessary. * * Return: * 0 if*@arg was already no more than @val. * -EINVAL if *@arg was greater than @val. */ static inline int comedi_check_trigger_arg_max(unsigned int *arg, unsigned int val) { … } /* * Must set dev->hw_dev if you wish to dma directly into comedi's buffer. * Also useful for retrieving a previously configured hardware device of * known bus type. Set automatically for auto-configured devices. * Automatically set to NULL when detaching hardware device. */ int comedi_set_hw_dev(struct comedi_device *dev, struct device *hw_dev); /** * comedi_buf_n_bytes_ready - Determine amount of unread data in buffer * @s: COMEDI subdevice. * * Determines the number of bytes of unread data in the asynchronous * acquisition data buffer for a subdevice. The data in question might not * have been fully "munged" yet. * * Returns: The amount of unread data in bytes. */ static inline unsigned int comedi_buf_n_bytes_ready(struct comedi_subdevice *s) { … } unsigned int comedi_buf_write_alloc(struct comedi_subdevice *s, unsigned int n); unsigned int comedi_buf_write_free(struct comedi_subdevice *s, unsigned int n); unsigned int comedi_buf_read_n_available(struct comedi_subdevice *s); unsigned int comedi_buf_read_alloc(struct comedi_subdevice *s, unsigned int n); unsigned int comedi_buf_read_free(struct comedi_subdevice *s, unsigned int n); unsigned int comedi_buf_write_samples(struct comedi_subdevice *s, const void *data, unsigned int nsamples); unsigned int comedi_buf_read_samples(struct comedi_subdevice *s, void *data, unsigned int nsamples); /* drivers.c - general comedi driver functions */ #define COMEDI_TIMEOUT_MS … int comedi_timeout(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, int (*cb)(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned long context), unsigned long context); unsigned int comedi_handle_events(struct comedi_device *dev, struct comedi_subdevice *s); int comedi_dio_insn_config(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data, unsigned int mask); unsigned int comedi_dio_update_state(struct comedi_subdevice *s, unsigned int *data); unsigned int comedi_bytes_per_scan_cmd(struct comedi_subdevice *s, struct comedi_cmd *cmd); unsigned int comedi_bytes_per_scan(struct comedi_subdevice *s); unsigned int comedi_nscans_left(struct comedi_subdevice *s, unsigned int nscans); unsigned int comedi_nsamples_left(struct comedi_subdevice *s, unsigned int nsamples); void comedi_inc_scan_progress(struct comedi_subdevice *s, unsigned int num_bytes); void *comedi_alloc_devpriv(struct comedi_device *dev, size_t size); int comedi_alloc_subdevices(struct comedi_device *dev, int num_subdevices); int comedi_alloc_subdev_readback(struct comedi_subdevice *s); int comedi_readback_insn_read(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data); int comedi_load_firmware(struct comedi_device *dev, struct device *hw_dev, const char *name, int (*cb)(struct comedi_device *dev, const u8 *data, size_t size, unsigned long context), unsigned long context); int __comedi_request_region(struct comedi_device *dev, unsigned long start, unsigned long len); int comedi_request_region(struct comedi_device *dev, unsigned long start, unsigned long len); void comedi_legacy_detach(struct comedi_device *dev); int comedi_auto_config(struct device *hardware_device, struct comedi_driver *driver, unsigned long context); void comedi_auto_unconfig(struct device *hardware_device); int comedi_driver_register(struct comedi_driver *driver); void comedi_driver_unregister(struct comedi_driver *driver); /** * module_comedi_driver() - Helper macro for registering a comedi driver * @__comedi_driver: comedi_driver struct * * Helper macro for comedi drivers which do not do anything special in module * init/exit. This eliminates a lot of boilerplate. Each module may only use * this macro once, and calling it replaces module_init() and module_exit(). */ #define module_comedi_driver(__comedi_driver) … #endif /* _COMEDIDEV_H */
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