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Diffstat (limited to 'drivers/staging/comedi/drivers/skel.c')
| -rw-r--r-- | drivers/staging/comedi/drivers/skel.c | 624 |
1 files changed, 624 insertions, 0 deletions
diff --git a/drivers/staging/comedi/drivers/skel.c b/drivers/staging/comedi/drivers/skel.c new file mode 100644 index 000000000000..c7700d134cc1 --- /dev/null +++ b/drivers/staging/comedi/drivers/skel.c @@ -0,0 +1,624 @@ +/* + comedi/drivers/skel.c + Skeleton code for a Comedi driver + + COMEDI - Linux Control and Measurement Device Interface + Copyright (C) 2000 David A. Schleef <ds@schleef.org> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +*/ +/* +Driver: skel +Description: Skeleton driver, an example for driver writers +Devices: +Author: ds +Updated: Mon, 18 Mar 2002 15:34:01 -0800 +Status: works + +This driver is a documented example on how Comedi drivers are +written. + +Configuration Options: + none +*/ + +/* + * The previous block comment is used to automatically generate + * documentation in Comedi and Comedilib. The fields: + * + * Driver: the name of the driver + * Description: a short phrase describing the driver. Don't list boards. + * Devices: a full list of the boards that attempt to be supported by + * the driver. Format is "(manufacturer) board name [comedi name]", + * where comedi_name is the name that is used to configure the board. + * See the comment near board_name: in the struct comedi_driver structure + * below. If (manufacturer) or [comedi name] is missing, the previous + * value is used. + * Author: you + * Updated: date when the _documentation_ was last updated. Use 'date -R' + * to get a value for this. + * Status: a one-word description of the status. Valid values are: + * works - driver works correctly on most boards supported, and + * passes comedi_test. + * unknown - unknown. Usually put there by ds. + * experimental - may not work in any particular release. Author + * probably wants assistance testing it. + * bitrotten - driver has not been update in a long time, probably + * doesn't work, and probably is missing support for significant + * Comedi interface features. + * untested - author probably wrote it "blind", and is believed to + * work, but no confirmation. + * + * These headers should be followed by a blank line, and any comments + * you wish to say about the driver. The comment area is the place + * to put any known bugs, limitations, unsupported features, supported + * command triggers, whether or not commands are supported on particular + * subdevices, etc. + * + * Somewhere in the comment should be information about configuration + * options that are used with comedi_config. + */ + +#include "../comedidev.h" + +#include <linux/pci.h> /* for PCI devices */ + +/* Imaginary registers for the imaginary board */ + +#define SKEL_SIZE 0 + +#define SKEL_START_AI_CONV 0 +#define SKEL_AI_READ 0 + +/* + * Board descriptions for two imaginary boards. Describing the + * boards in this way is optional, and completely driver-dependent. + * Some drivers use arrays such as this, other do not. + */ +struct skel_board { + const char *name; + int ai_chans; + int ai_bits; + int have_dio; +}; + +static const struct skel_board skel_boards[] = { + { + name: "skel-100", + ai_chans:16, + ai_bits: 12, + have_dio:1, + }, + { + name: "skel-200", + ai_chans:8, + ai_bits: 16, + have_dio:0, + }, +}; + +/* This is used by modprobe to translate PCI IDs to drivers. Should + * only be used for PCI and ISA-PnP devices */ +/* Please add your PCI vendor ID to comedidev.h, and it will be forwarded + * upstream. */ +#define PCI_VENDOR_ID_SKEL 0xdafe +static DEFINE_PCI_DEVICE_TABLE(skel_pci_table) = { + {PCI_VENDOR_ID_SKEL, 0x0100, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0}, + {PCI_VENDOR_ID_SKEL, 0x0200, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0}, + {0} +}; + +MODULE_DEVICE_TABLE(pci, skel_pci_table); + +/* + * Useful for shorthand access to the particular board structure + */ +#define thisboard ((const struct skel_board *)dev->board_ptr) + +/* this structure is for data unique to this hardware driver. If + several hardware drivers keep similar information in this structure, + feel free to suggest moving the variable to the struct comedi_device struct. */ +struct skel_private { + + int data; + + /* would be useful for a PCI device */ + struct pci_dev *pci_dev; + + /* Used for AO readback */ + unsigned int ao_readback[2]; +}; + +/* + * most drivers define the following macro to make it easy to + * access the private structure. + */ +#define devpriv ((struct skel_private *)dev->private) + +/* + * The struct comedi_driver structure tells the Comedi core module + * which functions to call to configure/deconfigure (attach/detach) + * the board, and also about the kernel module that contains + * the device code. + */ +static int skel_attach(struct comedi_device * dev, struct comedi_devconfig * it); +static int skel_detach(struct comedi_device * dev); +static struct comedi_driver driver_skel = { + driver_name:"dummy", + module:THIS_MODULE, + attach:skel_attach, + detach:skel_detach, +/* It is not necessary to implement the following members if you are + * writing a driver for a ISA PnP or PCI card */ + /* Most drivers will support multiple types of boards by + * having an array of board structures. These were defined + * in skel_boards[] above. Note that the element 'name' + * was first in the structure -- Comedi uses this fact to + * extract the name of the board without knowing any details + * about the structure except for its length. + * When a device is attached (by comedi_config), the name + * of the device is given to Comedi, and Comedi tries to + * match it by going through the list of board names. If + * there is a match, the address of the pointer is put + * into dev->board_ptr and driver->attach() is called. + * + * Note that these are not necessary if you can determine + * the type of board in software. ISA PnP, PCI, and PCMCIA + * devices are such boards. + */ + board_name:&skel_boards[0].name, + offset:sizeof(struct skel_board), + num_names:sizeof(skel_boards) / sizeof(struct skel_board), +}; + +static int skel_ai_rinsn(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data); +static int skel_ao_winsn(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data); +static int skel_ao_rinsn(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data); +static int skel_dio_insn_bits(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data); +static int skel_dio_insn_config(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data); +static int skel_ai_cmdtest(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_cmd * cmd); +static int skel_ns_to_timer(unsigned int *ns, int round); + +/* + * Attach is called by the Comedi core to configure the driver + * for a particular board. If you specified a board_name array + * in the driver structure, dev->board_ptr contains that + * address. + */ +static int skel_attach(struct comedi_device * dev, struct comedi_devconfig * it) +{ + struct comedi_subdevice *s; + + printk("comedi%d: skel: ", dev->minor); + +/* + * If you can probe the device to determine what device in a series + * it is, this is the place to do it. Otherwise, dev->board_ptr + * should already be initialized. + */ + /* dev->board_ptr = skel_probe(dev, it); */ + +/* + * Initialize dev->board_name. Note that we can use the "thisboard" + * macro now, since we just initialized it in the last line. + */ + dev->board_name = thisboard->name; + +/* + * Allocate the private structure area. alloc_private() is a + * convenient macro defined in comedidev.h. + */ + if (alloc_private(dev, sizeof(struct skel_private)) < 0) + return -ENOMEM; + +/* + * Allocate the subdevice structures. alloc_subdevice() is a + * convenient macro defined in comedidev.h. + */ + if (alloc_subdevices(dev, 3) < 0) + return -ENOMEM; + + s = dev->subdevices + 0; + /* dev->read_subdev=s; */ + /* analog input subdevice */ + s->type = COMEDI_SUBD_AI; + /* we support single-ended (ground) and differential */ + s->subdev_flags = SDF_READABLE | SDF_GROUND | SDF_DIFF; + s->n_chan = thisboard->ai_chans; + s->maxdata = (1 << thisboard->ai_bits) - 1; + s->range_table = &range_bipolar10; + s->len_chanlist = 16; /* This is the maximum chanlist length that + the board can handle */ + s->insn_read = skel_ai_rinsn; +/* +* s->subdev_flags |= SDF_CMD_READ; +* s->do_cmd = skel_ai_cmd; +*/ + s->do_cmdtest = skel_ai_cmdtest; + + s = dev->subdevices + 1; + /* analog output subdevice */ + s->type = COMEDI_SUBD_AO; + s->subdev_flags = SDF_WRITABLE; + s->n_chan = 1; + s->maxdata = 0xffff; + s->range_table = &range_bipolar5; + s->insn_write = skel_ao_winsn; + s->insn_read = skel_ao_rinsn; + + s = dev->subdevices + 2; + /* digital i/o subdevice */ + if (thisboard->have_dio) { + s->type = COMEDI_SUBD_DIO; + s->subdev_flags = SDF_READABLE | SDF_WRITABLE; + s->n_chan = 16; + s->maxdata = 1; + s->range_table = &range_digital; + s->insn_bits = skel_dio_insn_bits; + s->insn_config = skel_dio_insn_config; + } else { + s->type = COMEDI_SUBD_UNUSED; + } + + printk("attached\n"); + + return 0; +} + +/* + * _detach is called to deconfigure a device. It should deallocate + * resources. + * This function is also called when _attach() fails, so it should be + * careful not to release resources that were not necessarily + * allocated by _attach(). dev->private and dev->subdevices are + * deallocated automatically by the core. + */ +static int skel_detach(struct comedi_device * dev) +{ + printk("comedi%d: skel: remove\n", dev->minor); + + return 0; +} + +/* + * "instructions" read/write data in "one-shot" or "software-triggered" + * mode. + */ +static int skel_ai_rinsn(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data) +{ + int n, i; + unsigned int d; + unsigned int status; + + /* a typical programming sequence */ + + /* write channel to multiplexer */ + /* outw(chan,dev->iobase + SKEL_MUX); */ + + /* don't wait for mux to settle */ + + /* convert n samples */ + for (n = 0; n < insn->n; n++) { + /* trigger conversion */ + /* outw(0,dev->iobase + SKEL_CONVERT); */ + +#define TIMEOUT 100 + /* wait for conversion to end */ + for (i = 0; i < TIMEOUT; i++) { + status = 1; + /* status = inb(dev->iobase + SKEL_STATUS); */ + if (status) + break; + } + if (i == TIMEOUT) { + /* rt_printk() should be used instead of printk() + * whenever the code can be called from real-time. */ + rt_printk("timeout\n"); + return -ETIMEDOUT; + } + + /* read data */ + /* d = inw(dev->iobase + SKEL_AI_DATA); */ + d = 0; + + /* mangle the data as necessary */ + d ^= 1 << (thisboard->ai_bits - 1); + + data[n] = d; + } + + /* return the number of samples read/written */ + return n; +} + +static int skel_ai_cmdtest(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_cmd * cmd) +{ + int err = 0; + int tmp; + + /* cmdtest tests a particular command to see if it is valid. + * Using the cmdtest ioctl, a user can create a valid cmd + * and then have it executes by the cmd ioctl. + * + * cmdtest returns 1,2,3,4 or 0, depending on which tests + * the command passes. */ + + /* step 1: make sure trigger sources are trivially valid */ + + tmp = cmd->start_src; + cmd->start_src &= TRIG_NOW; + if (!cmd->start_src || tmp != cmd->start_src) + err++; + + tmp = cmd->scan_begin_src; + cmd->scan_begin_src &= TRIG_TIMER | TRIG_EXT; + if (!cmd->scan_begin_src || tmp != cmd->scan_begin_src) + err++; + + tmp = cmd->convert_src; + cmd->convert_src &= TRIG_TIMER | TRIG_EXT; + if (!cmd->convert_src || tmp != cmd->convert_src) + err++; + + tmp = cmd->scan_end_src; + cmd->scan_end_src &= TRIG_COUNT; + if (!cmd->scan_end_src || tmp != cmd->scan_end_src) + err++; + + tmp = cmd->stop_src; + cmd->stop_src &= TRIG_COUNT | TRIG_NONE; + if (!cmd->stop_src || tmp != cmd->stop_src) + err++; + + if (err) + return 1; + + /* step 2: make sure trigger sources are unique and mutually compatible */ + + /* note that mutual compatiblity is not an issue here */ + if (cmd->scan_begin_src != TRIG_TIMER && + cmd->scan_begin_src != TRIG_EXT) + err++; + if (cmd->convert_src != TRIG_TIMER && cmd->convert_src != TRIG_EXT) + err++; + if (cmd->stop_src != TRIG_COUNT && cmd->stop_src != TRIG_NONE) + err++; + + if (err) + return 2; + + /* step 3: make sure arguments are trivially compatible */ + + if (cmd->start_arg != 0) { + cmd->start_arg = 0; + err++; + } +#define MAX_SPEED 10000 /* in nanoseconds */ +#define MIN_SPEED 1000000000 /* in nanoseconds */ + + if (cmd->scan_begin_src == TRIG_TIMER) { + if (cmd->scan_begin_arg < MAX_SPEED) { + cmd->scan_begin_arg = MAX_SPEED; + err++; + } + if (cmd->scan_begin_arg > MIN_SPEED) { + cmd->scan_begin_arg = MIN_SPEED; + err++; + } + } else { + /* external trigger */ + /* should be level/edge, hi/lo specification here */ + /* should specify multiple external triggers */ + if (cmd->scan_begin_arg > 9) { + cmd->scan_begin_arg = 9; + err++; + } + } + if (cmd->convert_src == TRIG_TIMER) { + if (cmd->convert_arg < MAX_SPEED) { + cmd->convert_arg = MAX_SPEED; + err++; + } + if (cmd->convert_arg > MIN_SPEED) { + cmd->convert_arg = MIN_SPEED; + err++; + } + } else { + /* external trigger */ + /* see above */ + if (cmd->convert_arg > 9) { + cmd->convert_arg = 9; + err++; + } + } + + if (cmd->scan_end_arg != cmd->chanlist_len) { + cmd->scan_end_arg = cmd->chanlist_len; + err++; + } + if (cmd->stop_src == TRIG_COUNT) { + if (cmd->stop_arg > 0x00ffffff) { + cmd->stop_arg = 0x00ffffff; + err++; + } + } else { + /* TRIG_NONE */ + if (cmd->stop_arg != 0) { + cmd->stop_arg = 0; + err++; + } + } + + if (err) + return 3; + + /* step 4: fix up any arguments */ + + if (cmd->scan_begin_src == TRIG_TIMER) { + tmp = cmd->scan_begin_arg; + skel_ns_to_timer(&cmd->scan_begin_arg, + cmd->flags & TRIG_ROUND_MASK); + if (tmp != cmd->scan_begin_arg) + err++; + } + if (cmd->convert_src == TRIG_TIMER) { + tmp = cmd->convert_arg; + skel_ns_to_timer(&cmd->convert_arg, + cmd->flags & TRIG_ROUND_MASK); + if (tmp != cmd->convert_arg) + err++; + if (cmd->scan_begin_src == TRIG_TIMER && + cmd->scan_begin_arg < + cmd->convert_arg * cmd->scan_end_arg) { + cmd->scan_begin_arg = + cmd->convert_arg * cmd->scan_end_arg; + err++; + } + } + + if (err) + return 4; + + return 0; +} + +/* This function doesn't require a particular form, this is just + * what happens to be used in some of the drivers. It should + * convert ns nanoseconds to a counter value suitable for programming + * the device. Also, it should adjust ns so that it cooresponds to + * the actual time that the device will use. */ +static int skel_ns_to_timer(unsigned int *ns, int round) +{ + /* trivial timer */ + /* if your timing is done through two cascaded timers, the + * i8253_cascade_ns_to_timer() function in 8253.h can be + * very helpful. There are also i8254_load() and i8254_mm_load() + * which can be used to load values into the ubiquitous 8254 counters + */ + + return *ns; +} + +static int skel_ao_winsn(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data) +{ + int i; + int chan = CR_CHAN(insn->chanspec); + + printk("skel_ao_winsn\n"); + /* Writing a list of values to an AO channel is probably not + * very useful, but that's how the interface is defined. */ + for (i = 0; i < insn->n; i++) { + /* a typical programming sequence */ + /* outw(data[i],dev->iobase + SKEL_DA0 + chan); */ + devpriv->ao_readback[chan] = data[i]; + } + + /* return the number of samples read/written */ + return i; +} + +/* AO subdevices should have a read insn as well as a write insn. + * Usually this means copying a value stored in devpriv. */ +static int skel_ao_rinsn(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data) +{ + int i; + int chan = CR_CHAN(insn->chanspec); + + for (i = 0; i < insn->n; i++) + data[i] = devpriv->ao_readback[chan]; + + return i; +} + +/* DIO devices are slightly special. Although it is possible to + * implement the insn_read/insn_write interface, it is much more + * useful to applications if you implement the insn_bits interface. + * This allows packed reading/writing of the DIO channels. The + * comedi core can convert between insn_bits and insn_read/write */ +static int skel_dio_insn_bits(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data) +{ + if (insn->n != 2) + return -EINVAL; + + /* The insn data is a mask in data[0] and the new data + * in data[1], each channel cooresponding to a bit. */ + if (data[0]) { + s->state &= ~data[0]; + s->state |= data[0] & data[1]; + /* Write out the new digital output lines */ + /* outw(s->state,dev->iobase + SKEL_DIO); */ + } + + /* on return, data[1] contains the value of the digital + * input and output lines. */ + /* data[1]=inw(dev->iobase + SKEL_DIO); */ + /* or we could just return the software copy of the output values if + * it was a purely digital output subdevice */ + /* data[1]=s->state; */ + + return 2; +} + +static int skel_dio_insn_config(struct comedi_device * dev, struct comedi_subdevice * s, + struct comedi_insn * insn, unsigned int * data) +{ + int chan = CR_CHAN(insn->chanspec); + + /* The input or output configuration of each digital line is + * configured by a special insn_config instruction. chanspec + * contains the channel to be changed, and data[0] contains the + * value COMEDI_INPUT or COMEDI_OUTPUT. */ + switch (data[0]) { + case INSN_CONFIG_DIO_OUTPUT: + s->io_bits |= 1 << chan; + break; + case INSN_CONFIG_DIO_INPUT: + s->io_bits &= ~(1 << chan); + break; + case INSN_CONFIG_DIO_QUERY: + data[1] = + (s-> + io_bits & (1 << chan)) ? COMEDI_OUTPUT : COMEDI_INPUT; + return insn->n; + break; + default: + return -EINVAL; + break; + } + /* outw(s->io_bits,dev->iobase + SKEL_DIO_CONFIG); */ + + return insn->n; +} + +/* + * A convenient macro that defines init_module() and cleanup_module(), + * as necessary. + */ +COMEDI_INITCLEANUP(driver_skel); +/* If you are writing a PCI driver you should use COMEDI_PCI_INITCLEANUP instead. +*/ +/* COMEDI_PCI_INITCLEANUP(driver_skel, skel_pci_table) */ |