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Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  1 /*
  2     comedi/drivers/cb_pcimdda.c
  3     Computer Boards PCIM-DDA06-16 Comedi driver
  4     Author: Calin Culianu <calin@ajvar.org>
  5 
  6     COMEDI - Linux Control and Measurement Device Interface
  7     Copyright (C) 2000 David A. Schleef <ds@schleef.org>
  8 
  9     This program is free software; you can redistribute it and/or modify
 10     it under the terms of the GNU General Public License as published by
 11     the Free Software Foundation; either version 2 of the License, or
 12     (at your option) any later version.
 13 
 14     This program is distributed in the hope that it will be useful,
 15     but WITHOUT ANY WARRANTY; without even the implied warranty of
 16     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17     GNU General Public License for more details.
 18 
 19     You should have received a copy of the GNU General Public License
 20     along with this program; if not, write to the Free Software
 21     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 22 
 23 */
 24 /*
 25 Driver: cb_pcimdda
 26 Description: Measurement Computing PCIM-DDA06-16
 27 Devices: [Measurement Computing] PCIM-DDA06-16 (cb_pcimdda)
 28 Author: Calin Culianu <calin@ajvar.org>
 29 Updated: Mon, 14 Apr 2008 15:15:51 +0100
 30 Status: works
 31 
 32 All features of the PCIM-DDA06-16 board are supported.  This board
 33 has 6 16-bit AO channels, and the usual 8255 DIO setup.  (24 channels,
 34 configurable in banks of 8 and 4, etc.).  This board does not support commands.
 35 
 36 The board has a peculiar way of specifying AO gain/range settings -- You have
 37 1 jumper bank on the card, which either makes all 6 AO channels either
 38 5 Volt unipolar, 5V bipolar, 10 Volt unipolar or 10V bipolar.
 39 
 40 Since there is absolutely _no_ way to tell in software how this jumper is set
 41 (well, at least according  to the rather thin spec. from Measurement Computing
 42  that comes with the board), the driver assumes the jumper is at its factory
 43 default setting of +/-5V.
 44 
 45 Also of note is the fact that this board features another jumper, whose
 46 state is also completely invisible to software.  It toggles two possible AO
 47 output modes on the board:
 48 
 49   - Update Mode: Writing to an AO channel instantaneously updates the actual
 50     signal output by the DAC on the board (this is the factory default).
 51   - Simultaneous XFER Mode: Writing to an AO channel has no effect until
 52     you read from any one of the AO channels.  This is useful for loading
 53     all 6 AO values, and then reading from any one of the AO channels on the
 54     device to instantly update all 6 AO values in unison.  Useful for some
 55     control apps, I would assume?  If your jumper is in this setting, then you
 56     need to issue your comedi_data_write()s to load all the values you want,
 57     then issue one comedi_data_read() on any channel on the AO subdevice
 58     to initiate the simultaneous XFER.
 59 
 60 Configuration Options:
 61   [0] PCI bus (optional)
 62   [1] PCI slot (optional)
 63   [2] analog output range jumper setting
 64       0 == +/- 5 V
 65       1 == +/- 10 V
 66 */
 67 
 68 /*
 69     This is a driver for the Computer Boards PCIM-DDA06-16 Analog Output
 70     card.  This board has a unique register layout and as such probably
 71     deserves its own driver file.
 72 
 73     It is theoretically possible to integrate this board into the cb_pcidda
 74     file, but since that isn't my code, I didn't want to significantly
 75     modify that file to support this board (I thought it impolite to do so).
 76 
 77     At any rate, if you feel ambitious, please feel free to take
 78     the code out of this file and combine it with a more unified driver
 79     file.
 80 
 81     I would like to thank Timothy Curry <Timothy.Curry@rdec.redstone.army.mil>
 82     for lending me a board so that I could write this driver.
 83 
 84     -Calin Culianu <calin@ajvar.org>
 85  */
 86 
 87 #include "../comedidev.h"
 88 
 89 #include "comedi_pci.h"
 90 
 91 #include "8255.h"
 92 
 93 /* device ids of the cards we support -- currently only 1 card supported */
 94 #define PCI_ID_PCIM_DDA06_16 0x0053
 95 
 96 /*
 97  * This is straight from skel.c -- I did this in case this source file
 98  * will someday support more than 1 board...
 99  */
100 struct board_struct {
101         const char *name;
102         unsigned short device_id;
103         int ao_chans;
104         int ao_bits;
105         int dio_chans;
106         int dio_method;
107         int dio_offset;         /* how many bytes into the BADR are the DIO ports */
108         int regs_badrindex;     /* IO Region for the control, analog output,
109                                    and DIO registers */
110         int reg_sz;             /* number of bytes of registers in io region */
111 };
112 
113 enum DIO_METHODS {
114         DIO_NONE = 0,
115         DIO_8255,
116         DIO_INTERNAL            /* unimplemented */
117 };
118 
119 static const struct board_struct boards[] = {
120         {
121         .name = "cb_pcimdda06-16",
122         .device_id = PCI_ID_PCIM_DDA06_16,
123         .ao_chans = 6,
124         .ao_bits = 16,
125         .dio_chans = 24,
126         .dio_method = DIO_8255,
127         .dio_offset = 12,
128         .regs_badrindex = 3,
129         .reg_sz = 16,
130                 }
131 };
132 
133 /*
134  * Useful for shorthand access to the particular board structure
135  */
136 #define thisboard    ((const struct board_struct *)dev->board_ptr)
137 
138 #define REG_SZ (thisboard->reg_sz)
139 #define REGS_BADRINDEX (thisboard->regs_badrindex)
140 
141 /* This is used by modprobe to translate PCI IDs to drivers.  Should
142  * only be used for PCI and ISA-PnP devices */
143 /* Please add your PCI vendor ID to comedidev.h, and it will be forwarded
144  * upstream. */
145 static DEFINE_PCI_DEVICE_TABLE(pci_table) = {
146         {PCI_VENDOR_ID_COMPUTERBOARDS, PCI_ID_PCIM_DDA06_16, PCI_ANY_ID,
147                 PCI_ANY_ID, 0, 0, 0},
148         {0}
149 };
150 
151 MODULE_DEVICE_TABLE(pci, pci_table);
152 
153 /* this structure is for data unique to this hardware driver.  If
154    several hardware drivers keep similar information in this structure,
155    feel free to suggest moving the variable to the struct comedi_device struct.  */
156 struct board_private_struct {
157         unsigned long registers;        /* set by probe */
158         unsigned long dio_registers;
159         char attached_to_8255;  /* boolean */
160         char attached_successfully;     /* boolean */
161         /* would be useful for a PCI device */
162         struct pci_dev *pci_dev;
163 
164 #define MAX_AO_READBACK_CHANNELS 6
165         /* Used for AO readback */
166         unsigned int ao_readback[MAX_AO_READBACK_CHANNELS];
167 
168 };
169 
170 /*
171  * most drivers define the following macro to make it easy to
172  * access the private structure.
173  */
174 #define devpriv ((struct board_private_struct *)dev->private)
175 
176 /*
177  * The struct comedi_driver structure tells the Comedi core module
178  * which functions to call to configure/deconfigure (attach/detach)
179  * the board, and also about the kernel module that contains
180  * the device code.
181  */
182 static int attach(struct comedi_device *dev, struct comedi_devconfig *it);
183 static int detach(struct comedi_device *dev);
184 static struct comedi_driver cb_pcimdda_driver = {
185         .driver_name = "cb_pcimdda",
186         .module = THIS_MODULE,
187         .attach = attach,
188         .detach = detach,
189 };
190 
191 MODULE_AUTHOR("Calin A. Culianu <calin@rtlab.org>");
192 MODULE_DESCRIPTION("Comedi low-level driver for the Computerboards PCIM-DDA "
193         "series.  Currently only supports PCIM-DDA06-16 (which "
194         "also happens to be the only board in this series. :) ) ");
195 MODULE_LICENSE("GPL");
196 COMEDI_PCI_INITCLEANUP_NOMODULE(cb_pcimdda_driver, pci_table);
197 
198 static int ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
199         struct comedi_insn *insn, unsigned int *data);
200 static int ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
201         struct comedi_insn *insn, unsigned int *data);
202 
203 /*---------------------------------------------------------------------------
204   HELPER FUNCTION DECLARATIONS
205 -----------------------------------------------------------------------------*/
206 
207 /* returns a maxdata value for a given n_bits */
208 static inline unsigned int figure_out_maxdata(int bits)
209 {
210         return ((unsigned int) 1 << bits) - 1;
211 }
212 
213 /*
214  *  Probes for a supported device.
215  *
216  *  Prerequisite: private be allocated already inside dev
217  *
218  *  If the device is found, it returns 0 and has the following side effects:
219  *
220  *  o  assigns a struct pci_dev * to dev->private->pci_dev
221  *  o  assigns a struct board * to dev->board_ptr
222  *  o  sets dev->private->registers
223  *  o  sets dev->private->dio_registers
224  *
225  *  Otherwise, returns a -errno on error
226  */
227 static int probe(struct comedi_device *dev, const struct comedi_devconfig *it);
228 
229 /*---------------------------------------------------------------------------
230   FUNCTION DEFINITIONS
231 -----------------------------------------------------------------------------*/
232 
233 /*
234  * Attach is called by the Comedi core to configure the driver
235  * for a particular board.  If you specified a board_name array
236  * in the driver structure, dev->board_ptr contains that
237  * address.
238  */
239 static int attach(struct comedi_device *dev, struct comedi_devconfig *it)
240 {
241         struct comedi_subdevice *s;
242         int err;
243 
244 /*
245  * Allocate the private structure area.  alloc_private() is a
246  * convenient macro defined in comedidev.h.
247  * if this function fails (returns negative) then the private area is
248  * kfree'd by comedi
249  */
250         if (alloc_private(dev, sizeof(struct board_private_struct)) < 0)
251                 return -ENOMEM;
252 
253 /*
254  * If you can probe the device to determine what device in a series
255  * it is, this is the place to do it.  Otherwise, dev->board_ptr
256  * should already be initialized.
257  */
258         err = probe(dev, it);
259         if (err)
260                 return err;
261 
262 /* Output some info */
263         printk("comedi%d: %s: ", dev->minor, thisboard->name);
264 
265 /*
266  * Initialize dev->board_name.  Note that we can use the "thisboard"
267  * macro now, since we just initialized it in the last line.
268  */
269         dev->board_name = thisboard->name;
270 
271 /*
272  * Allocate the subdevice structures.  alloc_subdevice() is a
273  * convenient macro defined in comedidev.h.
274  */
275         if (alloc_subdevices(dev, 2) < 0)
276                 return -ENOMEM;
277 
278         s = dev->subdevices + 0;
279 
280         /* analog output subdevice */
281         s->type = COMEDI_SUBD_AO;
282         s->subdev_flags = SDF_WRITABLE | SDF_READABLE;
283         s->n_chan = thisboard->ao_chans;
284         s->maxdata = figure_out_maxdata(thisboard->ao_bits);
285         /* this is hard-coded here */
286         if (it->options[2]) {
287                 s->range_table = &range_bipolar10;
288         } else {
289                 s->range_table = &range_bipolar5;
290         }
291         s->insn_write = &ao_winsn;
292         s->insn_read = &ao_rinsn;
293 
294         s = dev->subdevices + 1;
295         /* digital i/o subdevice */
296         if (thisboard->dio_chans) {
297                 switch (thisboard->dio_method) {
298                 case DIO_8255:
299                         /* this is a straight 8255, so register us with the 8255 driver */
300                         subdev_8255_init(dev, s, NULL, devpriv->dio_registers);
301                         devpriv->attached_to_8255 = 1;
302                         break;
303                 case DIO_INTERNAL:
304                 default:
305                         printk("DIO_INTERNAL not implemented yet!\n");
306                         return -ENXIO;
307                         break;
308                 }
309         } else {
310                 s->type = COMEDI_SUBD_UNUSED;
311         }
312 
313         devpriv->attached_successfully = 1;
314 
315         printk("attached\n");
316 
317         return 1;
318 }
319 
320 /*
321  * _detach is called to deconfigure a device.  It should deallocate
322  * resources.
323  * This function is also called when _attach() fails, so it should be
324  * careful not to release resources that were not necessarily
325  * allocated by _attach().  dev->private and dev->subdevices are
326  * deallocated automatically by the core.
327  */
328 static int detach(struct comedi_device *dev)
329 {
330         if (devpriv) {
331 
332                 if (dev->subdevices && devpriv->attached_to_8255) {
333                         /* de-register us from the 8255 driver */
334                         subdev_8255_cleanup(dev, dev->subdevices + 2);
335                         devpriv->attached_to_8255 = 0;
336                 }
337 
338                 if (devpriv->pci_dev) {
339                         if (devpriv->registers) {
340                                 comedi_pci_disable(devpriv->pci_dev);
341                         }
342                         pci_dev_put(devpriv->pci_dev);
343                 }
344 
345                 if (devpriv->attached_successfully && thisboard)
346                         printk("comedi%d: %s: detached\n", dev->minor,
347                                 thisboard->name);
348 
349         }
350 
351         return 0;
352 }
353 
354 static int ao_winsn(struct comedi_device *dev, struct comedi_subdevice *s,
355         struct comedi_insn *insn, unsigned int *data)
356 {
357         int i;
358         int chan = CR_CHAN(insn->chanspec);
359         unsigned long offset = devpriv->registers + chan * 2;
360 
361         /* Writing a list of values to an AO channel is probably not
362          * very useful, but that's how the interface is defined. */
363         for (i = 0; i < insn->n; i++) {
364                 /*  first, load the low byte */
365                 outb((char)(data[i] & 0x00ff), offset);
366                 /*  next, write the high byte -- only after this is written is
367                    the channel voltage updated in the DAC, unless
368                    we're in simultaneous xfer mode (jumper on card)
369                    then a rinsn is necessary to actually update the DAC --
370                    see ao_rinsn() below... */
371                 outb((char)(data[i] >> 8 & 0x00ff), offset + 1);
372 
373                 /* for testing only.. the actual rinsn SHOULD do an inw!
374                    (see the stuff about simultaneous XFER mode on this board) */
375                 devpriv->ao_readback[chan] = data[i];
376         }
377 
378         /* return the number of samples read/written */
379         return i;
380 }
381 
382 /* AO subdevices should have a read insn as well as a write insn.
383 
384    Usually this means copying a value stored in devpriv->ao_readback.
385    However, since this board has this jumper setting called "Simultaneous
386    Xfer mode" (off by default), we will support it.  Simultaneaous xfer
387    mode is accomplished by loading ALL the values you want for AO in all the
388    channels, then READing off one of the AO registers to initiate the
389    instantaneous simultaneous update of all DAC outputs, which makes
390    all AO channels update simultaneously.  This is useful for some control
391    applications, I would imagine.
392 */
393 static int ao_rinsn(struct comedi_device *dev, struct comedi_subdevice *s,
394         struct comedi_insn *insn, unsigned int *data)
395 {
396         int i;
397         int chan = CR_CHAN(insn->chanspec);
398 
399         for (i = 0; i < insn->n; i++) {
400                 inw(devpriv->registers + chan * 2);
401                 /* should I set data[i] to the result of the actual read on the register
402                    or the cached unsigned int in devpriv->ao_readback[]? */
403                 data[i] = devpriv->ao_readback[chan];
404         }
405 
406         return i;
407 }
408 
409 /*---------------------------------------------------------------------------
410   HELPER FUNCTION DEFINITIONS
411 -----------------------------------------------------------------------------*/
412 
413 /*
414  *  Probes for a supported device.
415  *
416  *  Prerequisite: private be allocated already inside dev
417  *
418  *  If the device is found, it returns 0 and has the following side effects:
419  *
420  *  o  assigns a struct pci_dev * to dev->private->pci_dev
421  *  o  assigns a struct board * to dev->board_ptr
422  *  o  sets dev->private->registers
423  *  o  sets dev->private->dio_registers
424  *
425  *  Otherwise, returns a -errno on error
426  */
427 static int probe(struct comedi_device *dev, const struct comedi_devconfig *it)
428 {
429         struct pci_dev *pcidev;
430         int index;
431         unsigned long registers;
432 
433         for (pcidev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, NULL);
434                 pcidev != NULL;
435                 pcidev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, pcidev)) {
436                 /*  is it not a computer boards card? */
437                 if (pcidev->vendor != PCI_VENDOR_ID_COMPUTERBOARDS)
438                         continue;
439                 /*  loop through cards supported by this driver */
440                 for (index = 0; index < ARRAY_SIZE(boards); index++) {
441                         if (boards[index].device_id != pcidev->device)
442                                 continue;
443                         /*  was a particular bus/slot requested? */
444                         if (it->options[0] || it->options[1]) {
445                                 /*  are we on the wrong bus/slot? */
446                                 if (pcidev->bus->number != it->options[0] ||
447                                         PCI_SLOT(pcidev->devfn) !=
448                                         it->options[1]) {
449                                         continue;
450                                 }
451                         }
452                         /* found ! */
453 
454                         devpriv->pci_dev = pcidev;
455                         dev->board_ptr = boards + index;
456                         if (comedi_pci_enable(pcidev, thisboard->name)) {
457                                 printk("cb_pcimdda: Failed to enable PCI device and request regions\n");
458                                 return -EIO;
459                         }
460                         registers =
461                                 pci_resource_start(devpriv->pci_dev,
462                                 REGS_BADRINDEX);
463                         devpriv->registers = registers;
464                         devpriv->dio_registers
465                                 = devpriv->registers + thisboard->dio_offset;
466                         return 0;
467                 }
468         }
469 
470         printk("cb_pcimdda: No supported ComputerBoards/MeasurementComputing "
471                 "card found at the requested position\n");
472         return -ENODEV;
473 }
474 
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