3 functions for setting calibration
5 Copyright (C) 2003 Frank Mori Hess <fmhess@users.sourceforge.net
7 This library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation, version 2.1
12 This library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with this library; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
31 #include "libinternal.h"
33 static int set_calibration( comedi_t *dev, const comedi_calibration_t *parsed_file,
34 unsigned int cal_index );
36 static int check_cal_file( comedi_t *dev, const comedi_calibration_t *parsed_file )
38 if( strcmp( comedi_get_driver_name( dev ), parsed_file->driver_name ) )
40 COMEDILIB_DEBUG( 3, "driver name does not match '%s' from calibration file\n",
41 parsed_file->driver_name );
45 if( strcmp( comedi_get_board_name( dev ), parsed_file->board_name ) )
47 COMEDILIB_DEBUG( 3, "board name does not match '%s' from calibration file\n",
48 parsed_file->board_name );
55 static inline int valid_channel( const comedi_calibration_t *parsed_file,
56 unsigned int cal_index, unsigned int channel )
60 num_channels = parsed_file->settings[ cal_index ].num_channels;
61 if( num_channels == 0 ) return 1;
62 for( i = 0; i < num_channels; i++ )
64 if( parsed_file->settings[ cal_index ].channels[ i ] == channel )
71 static inline int valid_range( const comedi_calibration_t *parsed_file,
72 unsigned int cal_index, unsigned int range )
76 num_ranges = parsed_file->settings[ cal_index ].num_ranges;
77 if( num_ranges == 0 ) return 1;
78 for( i = 0; i < num_ranges; i++ )
80 if( parsed_file->settings[ cal_index ].ranges[ i ] == range )
87 static inline int valid_aref( const comedi_calibration_t *parsed_file,
88 unsigned int cal_index, unsigned int aref )
92 num_arefs = parsed_file->settings[ cal_index ].num_arefs;
93 if( num_arefs == 0 ) return 1;
94 for( i = 0; i < num_arefs; i++ )
96 if( parsed_file->settings[ cal_index ].arefs[ i ] == aref )
103 static int apply_calibration( comedi_t *dev, const comedi_calibration_t *parsed_file,
104 unsigned int subdev, unsigned int channel, unsigned int range, unsigned int aref )
106 int num_cals, i, retval;
109 num_cals = parsed_file->num_settings;
111 for( i = 0; i < num_cals; i++ )
113 if( parsed_file->settings[ i ].subdevice != subdev ) continue;
114 if( valid_range( parsed_file, i, range ) == 0 ) continue;
115 if( valid_channel( parsed_file, i, channel ) == 0 ) continue;
116 if( valid_aref( parsed_file, i, aref ) == 0 ) continue;
118 retval = set_calibration( dev, parsed_file, i );
119 if( retval < 0 ) return retval;
124 COMEDILIB_DEBUG( 3, "failed to find matching calibration\n" );
131 static int set_calibration( comedi_t *dev, const comedi_calibration_t *parsed_file,
132 unsigned int cal_index )
134 int i, retval, num_caldacs;
136 num_caldacs = parsed_file->settings[ cal_index ].num_caldacs;
137 COMEDILIB_DEBUG( 4, "num_caldacs %i\n", num_caldacs );
139 for( i = 0; i < num_caldacs; i++ )
141 comedi_caldac_t caldac;
143 caldac = parsed_file->settings[ cal_index ].caldacs[ i ];
144 COMEDILIB_DEBUG( 4, "subdev %i, ch %i, val %i\n", caldac.subdevice,
145 caldac.channel,caldac.value);
146 retval = comedi_data_write( dev, caldac.subdevice, caldac.channel,
147 0, 0, caldac.value );
148 if( retval < 0 ) return retval;
154 EXPORT_ALIAS_DEFAULT(_comedi_apply_parsed_calibration,comedi_apply_parsed_calibration,0.7.20);
155 int _comedi_apply_parsed_calibration( comedi_t *dev, unsigned int subdev, unsigned int channel,
156 unsigned int range, unsigned int aref, const comedi_calibration_t *calibration )
160 if(!valid_dev(dev)) return -1;
161 retval = check_cal_file( dev, calibration );
162 if( retval < 0 ) return retval;
164 retval = apply_calibration( dev, calibration, subdev, channel, range, aref );
168 /* munge characters in board name that will cause problems with file paths */
169 static void fixup_board_name( char *name )
171 while( ( name = strchr( name, '/' ) ) )
181 EXPORT_ALIAS_DEFAULT(_comedi_get_default_calibration_path,comedi_get_default_calibration_path,0.7.20);
182 char* _comedi_get_default_calibration_path( comedi_t *dev )
184 struct stat file_stats;
188 const char *driver_name;
191 if(!valid_dev(dev)) return NULL;
192 if( fstat( comedi_fileno( dev ), &file_stats ) < 0 )
194 COMEDILIB_DEBUG( 3, "failed to get file stats of comedi device file\n" );
198 driver_name = comedi_get_driver_name( dev );
199 if( driver_name == NULL )
203 temp = comedi_get_board_name( dev );
208 board_name = strdup( temp );
210 fixup_board_name( board_name );
211 err = asprintf( &file_path, LOCALSTATEDIR "/lib/comedi/calibrations/%s_%s_comedi%li",
212 driver_name, board_name, ( unsigned long ) minor( file_stats.st_rdev ) );
222 EXPORT_ALIAS_DEFAULT(_comedi_apply_calibration,comedi_apply_calibration,0.7.20);
223 int _comedi_apply_calibration( comedi_t *dev, unsigned int subdev, unsigned int channel,
224 unsigned int range, unsigned int aref, const char *cal_file_path )
226 char file_path[ 1024 ];
228 comedi_calibration_t *parsed_file;
232 strncpy( file_path, cal_file_path, sizeof( file_path ) );
237 temp = comedi_get_default_calibration_path( dev );
238 if( temp == NULL ) return -1;
239 strncpy( file_path, temp, sizeof( file_path ) );
243 parsed_file = comedi_parse_calibration_file( file_path );
244 if( parsed_file == NULL )
246 COMEDILIB_DEBUG( 3, "failed to parse calibration file\n" );
250 retval = comedi_apply_parsed_calibration( dev, subdev, channel, range, aref, parsed_file );
252 comedi_cleanup_calibration( parsed_file );
257 EXPORT_ALIAS_DEFAULT(_comedi_get_hardcal_converter, comedi_get_hardcal_converter, 0.8.0);
258 int _comedi_get_hardcal_converter(
259 comedi_t *dev, unsigned subdevice, unsigned channel, unsigned range,
260 enum comedi_conversion_direction direction,
261 comedi_polynomial_t* polynomial)
263 comedi_range *range_ptr = comedi_get_range(dev, subdevice, channel, range);
266 if(range_ptr == NULL)
270 maxdata = comedi_get_maxdata(dev, subdevice, channel);
275 polynomial->order = 1;
278 case COMEDI_TO_PHYSICAL:
279 polynomial->expansion_origin = 0.;
280 polynomial->coefficients[0] = range_ptr->min;
281 polynomial->coefficients[1] = (range_ptr->max - range_ptr->min) / maxdata;
283 case COMEDI_FROM_PHYSICAL:
284 polynomial->expansion_origin = range_ptr->min;
285 polynomial->coefficients[0] = 0.;
286 polynomial->coefficients[1] = maxdata / (range_ptr->max - range_ptr->min);
292 EXPORT_ALIAS_DEFAULT(_comedi_get_softcal_converter, comedi_get_softcal_converter, 0.8.0);
293 int _comedi_get_softcal_converter(
294 unsigned subdevice, unsigned channel, unsigned range,
295 enum comedi_conversion_direction direction,
296 const comedi_calibration_t *calibration, comedi_polynomial_t* polynomial)
300 for(i = 0; i < calibration->num_settings; ++i)
302 if(calibration->settings[i].subdevice != subdevice) continue;
303 if(valid_channel(calibration, i, channel) == 0) continue;
304 if(valid_range(calibration, i, range) == 0) continue;
307 case COMEDI_TO_PHYSICAL:
308 if(calibration->settings[i].soft_calibration.to_phys == NULL)
312 *polynomial = *calibration->settings[i].soft_calibration.to_phys;
314 case COMEDI_FROM_PHYSICAL:
315 if(calibration->settings[i].soft_calibration.from_phys == NULL)
319 *polynomial = *calibration->settings[i].soft_calibration.from_phys;
327 static double apply_polynomial(const comedi_polynomial_t *polynomial, double input)
332 assert(polynomial->order < COMEDI_MAX_NUM_POLYNOMIAL_COEFFICIENTS);
333 for(i = 0; i <= polynomial->order; ++i)
335 value += polynomial->coefficients[i] * term;
336 term *= input - polynomial->expansion_origin;
341 EXPORT_ALIAS_DEFAULT(_comedi_to_physical, comedi_to_physical, 0.8.0);
342 double _comedi_to_physical(lsampl_t data,
343 const comedi_polynomial_t *conversion_polynomial)
345 return apply_polynomial(conversion_polynomial, data);
348 EXPORT_ALIAS_DEFAULT(_comedi_from_physical, comedi_from_physical, 0.8.0);
349 lsampl_t _comedi_from_physical(double data,
350 const comedi_polynomial_t *conversion_polynomial)
352 return nearbyint(apply_polynomial(conversion_polynomial, data));