https://github.com/torvalds/linux
Tip revision: 1e4b044d22517cae7047c99038abb444423243ca authored by Linus Torvalds on 08 July 2018, 23:34:02 UTC
Linux 4.18-rc4
Linux 4.18-rc4
Tip revision: 1e4b044
comedidev.h
/* 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 <ds@schleef.org>
*/
#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 "comedi.h"
#define COMEDI_VERSION(a, b, c) (((a) << 16) + ((b) << 8) + (c))
#define COMEDI_VERSION_CODE COMEDI_VERSION(COMEDI_MAJORVERSION, \
COMEDI_MINORVERSION, COMEDI_MICROVERSION)
#define COMEDI_RELEASE VERSION
#define COMEDI_NUM_BOARD_MINORS 0x30
/**
* 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_device *device;
int index;
int type;
int n_chan;
int subdev_flags;
int len_chanlist; /* maximum length of channel/gain list */
void *private;
struct comedi_async *async;
void *lock;
void *busy;
unsigned int runflags;
spinlock_t spin_lock; /* generic spin-lock for COMEDI and drivers */
unsigned int io_bits;
unsigned int maxdata; /* if maxdata==0, use list */
const unsigned int *maxdata_list; /* list is channel specific */
const struct comedi_lrange *range_table;
const struct comedi_lrange *const *range_table_list;
unsigned int *chanlist; /* driver-owned chanlist (not used) */
int (*insn_read)(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data);
int (*insn_write)(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data);
int (*insn_bits)(struct comedi_device *dev, struct comedi_subdevice *s,
struct comedi_insn *insn, unsigned int *data);
int (*insn_config)(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_insn *insn,
unsigned int *data);
int (*do_cmd)(struct comedi_device *dev, struct comedi_subdevice *s);
int (*do_cmdtest)(struct comedi_device *dev,
struct comedi_subdevice *s,
struct comedi_cmd *cmd);
int (*poll)(struct comedi_device *dev, struct comedi_subdevice *s);
int (*cancel)(struct comedi_device *dev, struct comedi_subdevice *s);
/* called when the buffer changes */
int (*buf_change)(struct comedi_device *dev,
struct comedi_subdevice *s);
void (*munge)(struct comedi_device *dev, struct comedi_subdevice *s,
void *data, unsigned int num_bytes,
unsigned int start_chan_index);
enum dma_data_direction async_dma_dir;
unsigned int state;
struct device *class_dev;
int minor;
unsigned int *readback;
};
/**
* 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 {
void *virt_addr;
dma_addr_t dma_addr;
};
/**
* 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 device *dma_hw_dev;
struct comedi_buf_page *page_list;
unsigned int n_pages;
enum dma_data_direction dma_dir;
struct kref refcount;
};
/**
* 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 {
void *prealloc_buf;
unsigned int prealloc_bufsz;
struct comedi_buf_map *buf_map;
unsigned int max_bufsize;
unsigned int buf_write_count;
unsigned int buf_write_alloc_count;
unsigned int buf_read_count;
unsigned int buf_read_alloc_count;
unsigned int buf_write_ptr;
unsigned int buf_read_ptr;
unsigned int cur_chan;
unsigned int scans_done;
unsigned int scan_progress;
unsigned int munge_chan;
unsigned int munge_count;
unsigned int munge_ptr;
unsigned int events;
struct comedi_cmd cmd;
wait_queue_head_t wait_head;
unsigned int cb_mask;
int (*inttrig)(struct comedi_device *dev, struct comedi_subdevice *s,
unsigned int x);
};
/**
* 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 {
COMEDI_CB_EOS = BIT(0),
COMEDI_CB_EOA = BIT(1),
COMEDI_CB_BLOCK = BIT(2),
COMEDI_CB_EOBUF = BIT(3),
COMEDI_CB_ERROR = BIT(4),
COMEDI_CB_OVERFLOW = BIT(5),
/* masks */
COMEDI_CB_ERROR_MASK = (COMEDI_CB_ERROR | COMEDI_CB_OVERFLOW),
COMEDI_CB_CANCEL_MASK = (COMEDI_CB_EOA | COMEDI_CB_ERROR_MASK)
};
/**
* 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 {
/* private: */
struct comedi_driver *next; /* Next in list of COMEDI drivers. */
/* public: */
const char *driver_name;
struct module *module;
int (*attach)(struct comedi_device *dev, struct comedi_devconfig *it);
void (*detach)(struct comedi_device *dev);
int (*auto_attach)(struct comedi_device *dev, unsigned long context);
unsigned int num_names;
const char *const *board_name;
int offset;
};
/**
* 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.
*
* 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 {
int use_count;
struct comedi_driver *driver;
struct comedi_8254 *pacer;
void *private;
struct device *class_dev;
int minor;
unsigned int detach_count;
struct device *hw_dev;
const char *board_name;
const void *board_ptr;
bool attached:1;
bool ioenabled:1;
spinlock_t spinlock; /* generic spin-lock for low-level driver */
struct mutex mutex; /* generic mutex for COMEDI core */
struct rw_semaphore attach_lock;
struct kref refcount;
int n_subdevices;
struct comedi_subdevice *subdevices;
/* dumb */
void __iomem *mmio;
unsigned long iobase;
unsigned long iolen;
unsigned int irq;
struct comedi_subdevice *read_subdev;
struct comedi_subdevice *write_subdev;
struct fasync_struct *async_queue;
int (*open)(struct comedi_device *dev);
void (*close)(struct comedi_device *dev);
};
/*
* 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) {(a) * 1e6, (b) * 1e6, 0}
#define RANGE_ext(a, b) {(a) * 1e6, (b) * 1e6, RF_EXTERNAL}
#define RANGE_mA(a, b) {(a) * 1e6, (b) * 1e6, UNIT_mA}
#define RANGE_unitless(a, b) {(a) * 1e6, (b) * 1e6, 0}
#define BIP_RANGE(a) {-(a) * 1e6, (a) * 1e6, 0}
#define UNI_RANGE(a) {0, (a) * 1e6, 0}
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 range_unipolar5
/**
* 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
* 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 {
int length;
struct comedi_krange range[];
};
/**
* 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)
{
return s->range_table->range[range].min < 0;
}
/**
* 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)
{
return s->range_table->range[range].min >= 0;
}
/**
* 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)
{
return !!(s->range_table->range[range].flags & RF_EXTERNAL);
}
/**
* 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)
{
return s->range_table_list[chan]->range[range].min < 0;
}
/**
* 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)
{
return s->range_table_list[chan]->range[range].min >= 0;
}
/**
* 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)
{
return !!(s->range_table_list[chan]->range[range].flags & RF_EXTERNAL);
}
/**
* 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)
{
return val ^ s->maxdata ^ (s->maxdata >> 1);
}
/**
* 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)
{
return s->subdev_flags & SDF_LSAMPL ? sizeof(int) : sizeof(short);
}
/**
* 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)
{
return s->subdev_flags & SDF_LSAMPL ? 2 : 1;
}
/**
* 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)
{
return nbytes >> comedi_sample_shift(s);
}
/**
* 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)
{
return nsamples << comedi_sample_shift(s);
}
/**
* 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)
{
unsigned int orig_src = *src;
*src = orig_src & flags;
if (*src == TRIG_INVALID || *src != orig_src)
return -EINVAL;
return 0;
}
/**
* 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)
{
/* this test is true if more than one _src bit is set */
if ((src & (src - 1)) != 0)
return -EINVAL;
return 0;
}
/**
* 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)
{
if (*arg != val) {
*arg = val;
return -EINVAL;
}
return 0;
}
/**
* 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)
{
if (*arg < val) {
*arg = val;
return -EINVAL;
}
return 0;
}
/**
* 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)
{
if (*arg > val) {
*arg = val;
return -EINVAL;
}
return 0;
}
/*
* 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)
{
return s->async->buf_write_count - s->async->buf_read_count;
}
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 1000
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(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) \
module_driver(__comedi_driver, comedi_driver_register, \
comedi_driver_unregister)
#endif /* _COMEDIDEV_H */