From ace7aa7f6442444848a731fcb3a445039cda32dd Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Tue, 9 Feb 2016 15:17:22 +0000 Subject: [PATCH] staging: comedi: comedi.h: add kernel-doc comments to struct types Add "kernel-doc"-formatted comments to the COMEDI `struct` declarations used with ioctls. Don't bother documenting `struct comedi_trig` as it is obsolete and not supported. Signed-off-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/comedi.h | 332 +++++++++++++++++++++++++++++++- 1 file changed, 325 insertions(+), 7 deletions(-) diff --git a/drivers/staging/comedi/comedi.h b/drivers/staging/comedi/comedi.h index 9ef0963101da..2ab48ce5c5d0 100644 --- a/drivers/staging/comedi/comedi.h +++ b/drivers/staging/comedi/comedi.h @@ -491,6 +491,19 @@ struct comedi_trig { unsigned int unused[3]; }; +/** + * struct comedi_insn - COMEDI instruction + * @insn: COMEDI instruction type (%INSN_xxx). + * @n: Length of @data[]. + * @data: Pointer to data array operated on by the instruction. + * @subdev: Subdevice index. + * @chanspec: A packed "chanspec" value consisting of channel number, + * analog range index, analog reference type, and flags. + * @unused: Reserved for future use. + * + * This is used with the %COMEDI_INSN ioctl, and indirectly with the + * %COMEDI_INSNLIST ioctl. + */ struct comedi_insn { unsigned int insn; unsigned int n; @@ -500,11 +513,95 @@ struct comedi_insn { unsigned int unused[3]; }; +/** + * struct comedi_insnlist - list of COMEDI instructions + * @n_insns: Number of COMEDI instructions. + * @insns: Pointer to array COMEDI instructions. + * + * This is used with the %COMEDI_INSNLIST ioctl. + */ struct comedi_insnlist { unsigned int n_insns; struct comedi_insn __user *insns; }; +/** + * struct comedi_cmd - COMEDI asynchronous acquisition command details + * @subdev: Subdevice index. + * @flags: Command flags (%CMDF_xxx). + * @start_src: "Start acquisition" trigger source (%TRIG_xxx). + * @start_arg: "Start acquisition" trigger argument. + * @scan_begin_src: "Scan begin" trigger source. + * @scan_begin_arg: "Scan begin" trigger argument. + * @convert_src: "Convert" trigger source. + * @convert_arg: "Convert" trigger argument. + * @scan_end_src: "Scan end" trigger source. + * @scan_end_arg: "Scan end" trigger argument. + * @stop_src: "Stop acquisition" trigger source. + * @stop_arg: "Stop acquisition" trigger argument. + * @chanlist: Pointer to array of "chanspec" values, containing a + * sequence of channel numbers packed with analog range + * index, etc. + * @chanlist_len: Number of channels in sequence. + * @data: Pointer to miscellaneous set-up data (not used). + * @data_len: Length of miscellaneous set-up data. + * + * This is used with the %COMEDI_CMD or %COMEDI_CMDTEST ioctl to set-up + * or validate an asynchronous acquisition command. The ioctl may modify + * the &struct comedi_cmd and copy it back to the caller. + * + * Optional command @flags values that can be ORed together... + * + * %CMDF_BOGUS - makes %COMEDI_CMD ioctl return error %EAGAIN instead of + * starting the command. + * + * %CMDF_PRIORITY - requests "hard real-time" processing (which is not + * supported in this version of COMEDI). + * + * %CMDF_WAKE_EOS - requests the command makes data available for reading + * after every "scan" period. + * + * %CMDF_WRITE - marks the command as being in the "write" (to device) + * direction. This does not need to be specified by the caller unless the + * subdevice supports commands in either direction. + * + * %CMDF_RAWDATA - prevents the command from "munging" the data between the + * COMEDI sample format and the raw hardware sample format. + * + * %CMDF_ROUND_NEAREST - requests timing periods to be rounded to nearest + * supported values. + * + * %CMDF_ROUND_DOWN - requests timing periods to be rounded down to supported + * values (frequencies rounded up). + * + * %CMDF_ROUND_UP - requests timing periods to be rounded up to supported + * values (frequencies rounded down). + * + * Trigger source values for @start_src, @scan_begin_src, @convert_src, + * @scan_end_src, and @stop_src... + * + * %TRIG_ANY - "all ones" value used to test which trigger sources are + * supported. + * + * %TRIG_INVALID - "all zeroes" value used to indicate that all requested + * trigger sources are invalid. + * + * %TRIG_NONE - never trigger (often used as a @stop_src value). + * + * %TRIG_NOW - trigger after '_arg' nanoseconds. + * + * %TRIG_FOLLOW - trigger follows another event. + * + * %TRIG_TIMER - trigger every '_arg' nanoseconds. + * + * %TRIG_COUNT - trigger when count '_arg' is reached. + * + * %TRIG_EXT - trigger on external signal specified by '_arg'. + * + * %TRIG_INT - trigger on internal, software trigger specified by '_arg'. + * + * %TRIG_OTHER - trigger on other, driver-defined signal specified by '_arg'. + */ struct comedi_cmd { unsigned int subdev; unsigned int flags; @@ -524,13 +621,31 @@ struct comedi_cmd { unsigned int stop_src; unsigned int stop_arg; - unsigned int *chanlist; /* channel/range list */ + unsigned int *chanlist; unsigned int chanlist_len; - short __user *data; /* data list, size depends on subd flags */ + short __user *data; unsigned int data_len; }; +/** + * struct comedi_chaninfo - used to retrieve per-channel information + * @subdev: Subdevice index. + * @maxdata_list: Optional pointer to per-channel maximum data values. + * @flaglist: Optional pointer to per-channel flags. + * @rangelist: Optional pointer to per-channel range types. + * @unused: Reserved for future use. + * + * This is used with the %COMEDI_CHANINFO ioctl to get per-channel information + * for the subdevice. Use of this requires knowledge of the number of channels + * and subdevice flags obtained using the %COMEDI_SUBDINFO ioctl. + * + * The @maxdata_list member must be %NULL unless the %SDF_MAXDATA subdevice + * flag is set. The @flaglist member must be %NULL unless the %SDF_FLAGS + * subdevice flag is set. The @rangelist member must be %NULL unless the + * %SDF_RANGETYPE subdevice flag is set. Otherwise, the arrays they point to + * must be at least as long as the number of channels. + */ struct comedi_chaninfo { unsigned int subdev; unsigned int __user *maxdata_list; @@ -539,17 +654,157 @@ struct comedi_chaninfo { unsigned int unused[4]; }; +/** + * struct comedi_rangeinfo - used to retrieve the range table for a channel + * @range_type: Encodes subdevice index (bits 27:24), channel index + * (bits 23:16) and range table length (bits 15:0). + * @range_ptr: Pointer to array of @struct comedi_krange to be filled + * in with the range table for the channel or subdevice. + * + * This is used with the %COMEDI_RANGEINFO ioctl to retrieve the range table + * for a specific channel (if the subdevice has the %SDF_RANGETYPE flag set to + * indicate that the range table depends on the channel), or for the subdevice + * as a whole (if the %SDF_RANGETYPE flag is clear, indicating the range table + * is shared by all channels). + * + * The @range_type value is an input to the ioctl and comes from a previous + * use of the %COMEDI_SUBDINFO ioctl (if the %SDF_RANGETYPE flag is clear), + * or the %COMEDI_CHANINFO ioctl (if the %SDF_RANGETYPE flag is set). + */ struct comedi_rangeinfo { unsigned int range_type; void __user *range_ptr; }; +/** + * struct comedi_krange - describes a range in a range table + * @min: Minimum value in millionths (1e-6) of a unit. + * @max: Maximum value in millionths (1e-6) of a unit. + * @flags: Indicates the units (in bits 7:0) OR'ed with optional flags. + * + * A range table is associated with a single channel, or with all channels in a + * subdevice, and a list of one or more ranges. A %struct comedi_krange + * describes the physical range of units for one of those ranges. Sample + * values in COMEDI are unsigned from %0 up to some 'maxdata' value. The + * mapping from sample values to physical units is assumed to be nomimally + * linear (for the purpose of describing the range), with sample value %0 + * mapping to @min, and the 'maxdata' sample value mapping to @max. + * + * The currently defined units are %UNIT_volt (%0), %UNIT_mA (%1), and + * %UNIT_none (%2). The @min and @max values are the physical range multiplied + * by 1e6, so a @max value of %1000000 (with %UNIT_volt) represents a maximal + * value of 1 volt. + * + * The only defined flag value is %RF_external (%1 << %8), indicating that the + * the range needs to be multiplied by an external reference. + */ struct comedi_krange { - int min; /* fixed point, multiply by 1e-6 */ - int max; /* fixed point, multiply by 1e-6 */ + int min; + int max; unsigned int flags; }; +/** + * struct comedi_subdinfo - used to retrieve information about a subdevice + * @type: Type of subdevice from &enum comedi_subdevice_type. + * @n_chan: Number of channels the subdevice supports. + * @subd_flags: A mixture of static and dynamic flags describing + * aspects of the subdevice and its current state. + * @timer_type: Timer type. Always set to %5 ("nanosecond timer"). + * @len_chanlist: Maximum length of a channel list if the subdevice + * supports asynchronous acquisition commands. + * @maxdata: Maximum sample value for all channels if the + * %SDF_MAXDATA subdevice flag is clear. + * @flags: Channel flags for all channels if the %SDF_FLAGS + * subdevice flag is clear. + * @range_type: The range type for all channels if the %SDF_RANGETYPE + * subdevice flag is clear. Encodes the subdevice index + * (bits 27:24), a dummy channel index %0 (bits 23:16), + * and the range table length (bits 15:0). + * @settling_time_0: Not used. + * @insn_bits_support: Set to %COMEDI_SUPPORTED if the subdevice supports the + * %INSN_BITS instruction, or to %COMEDI_UNSUPPORTED if it + * does not. + * @unused: Reserved for future use. + * + * This is used with the %COMEDI_SUBDINFO ioctl which copies an array of + * &struct comedi_subdinfo back to user space, with one element per subdevice. + * Use of this requires knowledge of the number of subdevices obtained from + * the %COMEDI_DEVINFO ioctl. + * + * These are the @subd_flags values that may be ORed together... + * + * %SDF_BUSY - the subdevice is busy processing an asynchronous command or a + * synchronous instruction. + * + * %SDF_BUSY_OWNER - the subdevice is busy processing an asynchronous + * acquisition command started on the current file object (the file object + * issuing the %COMEDI_SUBDINFO ioctl). + * + * %SDF_LOCKED - the subdevice is locked by a %COMEDI_LOCK ioctl. + * + * %SDF_LOCK_OWNER - the subdevice is locked by a %COMEDI_LOCK ioctl from the + * current file object. + * + * %SDF_MAXDATA - maximum sample values are channel-specific. + * + * %SDF_FLAGS - channel flags are channel-specific. + * + * %SDF_RANGETYPE - range types are channel-specific. + * + * %SDF_MODE0 (aliased as %SDF_PWM_COUNTER) - the subdevice can do mode 0 (?) + * or PWM can switch off automatically. + * + * %SDF_MODE1 (aliased as %SDF_PWM_HBRIDGE) - the subdevice can do mode 1 (?) + * or PWM is signed (H-bridge). + * + * %SDF_MODE2 - the subdevice can do mode 2 (?). + * + * %SDF_MODE3 - the subdevice can do mode 3 (?). + * + * %SDF_MODE4 - the subdevice can do mode 4 (?). + * + * %SDF_CMD - the subdevice supports asynchronous commands. + * + * %SDF_SOFT_CALIBRATED - the subdevice uses software calibration. + * + * %SDF_CMD_WRITE - the subdevice supports asynchronous commands in the output + * ("write") direction. + * + * %SDF_CMD_READ - the subdevice supports asynchronous commands in the input + * ("read") direction. + * + * %SDF_READABLE - the subdevice is readable (e.g. analog input). + * + * %SDF_WRITABLE (aliased as %SDF_WRITEABLE) - the subdevice is writable (e.g. + * analog output). + * + * %SDF_INTERNAL - the subdevice has no externally visible lines. + * + * %SDF_GROUND - the subdevice can use ground as an analog reference. + * + * %SDF_COMMON - the subdevice can use a common analog reference. + * + * %SDF_DIFF - the subdevice can use differential inputs (or outputs). + * + * %SDF_OTHER - the subdevice can use some other analog reference. + * + * %SDF_DITHER - the subdevice can do dithering. + * + * %SDF_DEGLITCH - the subdevice can do deglitching. + * + * %SDF_MMAP - this is never set. + * + * %SDF_RUNNING - an asynchronous command is still running. + * + * %SDF_LSAMPL - the subdevice uses "long" (32-bit) samples (for asynchronous + * command data). + * + * %SDF_PACKED - the subdevice packs several DIO samples into a single sample + * (for asynchronous command data). + * + * No "channel flags" (@flags) values are currently defined. + */ struct comedi_subdinfo { unsigned int type; unsigned int n_chan; @@ -557,14 +812,26 @@ struct comedi_subdinfo { unsigned int timer_type; unsigned int len_chanlist; unsigned int maxdata; - unsigned int flags; /* channel flags */ - unsigned int range_type; /* lookup in kernel */ + unsigned int flags; + unsigned int range_type; unsigned int settling_time_0; - /* see support_level enum for values */ unsigned insn_bits_support; unsigned int unused[8]; }; +/** + * struct comedi_devinfo - used to retrieve information about a COMEDI device + * @version_code: COMEDI version code. + * @n_subdevs: Number of subdevices the device has. + * @driver_name: Null-terminated COMEDI driver name. + * @board_name: Null-terminated COMEDI board name. + * @read_subdevice: Index of the current "read" subdevice (%-1 if none). + * @write_subdevice: Index of the current "write" subdevice (%-1 if none). + * @unused: Reserved for future use. + * + * This is used with the %COMEDI_DEVINFO ioctl to get basic information about + * the device. + */ struct comedi_devinfo { unsigned int version_code; unsigned int n_subdevs; @@ -575,11 +842,45 @@ struct comedi_devinfo { int unused[30]; }; +/** + * struct comedi_devconfig - used to configure a legacy COMEDI device + * @board_name: Null-terminated string specifying the type of board + * to configure. + * @options: An array of integer configuration options. + * + * This is used with the %COMEDI_DEVCONFIG ioctl to configure a "legacy" COMEDI + * device, such as an ISA card. Not all COMEDI drivers support this. Those + * that do either expect the specified board name to match one of a list of + * names registered with the COMEDI core, or expect the specified board name + * to match the COMEDI driver name itself. The configuration options are + * handled in a driver-specific manner. + */ struct comedi_devconfig { char board_name[COMEDI_NAMELEN]; int options[COMEDI_NDEVCONFOPTS]; }; +/** + * struct comedi_bufconfig - used to set or get buffer size for a subdevice + * @subdevice: Subdevice index. + * @flags: Not used. + * @maximum_size: Maximum allowed buffer size. + * @size: Buffer size. + * @unused: Reserved for future use. + * + * This is used with the %COMEDI_BUFCONFIG ioctl to get or configure the + * maximum buffer size and current buffer size for a COMEDI subdevice that + * supports asynchronous commands. If the subdevice does not support + * asynchronous commands, @maximum_size and @size are ignored and set to 0. + * + * On ioctl input, non-zero values of @maximum_size and @size specify a + * new maximum size and new current size (in bytes), respectively. These + * will by rounded up to a multiple of %PAGE_SIZE. Specifying a new maximum + * size requires admin capabilities. + * + * On ioctl output, @maximum_size and @size and set to the current maximum + * buffer size and current buffer size, respectively. + */ struct comedi_bufconfig { unsigned int subdevice; unsigned int flags; @@ -590,6 +891,23 @@ struct comedi_bufconfig { unsigned int unused[4]; }; +/** + * struct comedi_bufinfo - used to manipulate buffer position for a subdevice + * @subdevice: Subdevice index. + * @bytes_read: Specify amount to advance read position for an + * asynchronous command in the input ("read") direction. + * @buf_write_ptr: Current write position (index) within the buffer. + * @buf_read_ptr: Current read position (index) within the buffer. + * @buf_write_count: Total amount written, modulo 2^32. + * @buf_read_count: Total amount read, modulo 2^32. + * @bytes_written: Specify amount to advance write position for an + * asynchronous command in the output ("write") direction. + * @unused: Reserved for future use. + * + * This is used with the %COMEDI_BUFINFO ioctl to optionally advance the + * current read or write position in an asynchronous acquisition data buffer, + * and to get the current read and write positions in the buffer. + */ struct comedi_bufinfo { unsigned int subdevice; unsigned int bytes_read; -- 2.20.1