1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * comedi/drivers/cb_pcidda.c
4  * Driver for the ComputerBoards / MeasurementComputing PCI-DDA series.
5  *
6  * Copyright (C) 2001 Ivan Martinez <ivanmr@altavista.com>
7  * Copyright (C) 2001 Frank Mori Hess <fmhess@users.sourceforge.net>
8  *
9  * COMEDI - Linux Control and Measurement Device Interface
10  * Copyright (C) 1997-8 David A. Schleef <ds@schleef.org>
11  */
12 
13 /*
14  * Driver: cb_pcidda
15  * Description: MeasurementComputing PCI-DDA series
16  * Devices: [Measurement Computing] PCI-DDA08/12 (pci-dda08/12),
17  *   PCI-DDA04/12 (pci-dda04/12), PCI-DDA02/12 (pci-dda02/12),
18  *   PCI-DDA08/16 (pci-dda08/16), PCI-DDA04/16 (pci-dda04/16),
19  *   PCI-DDA02/16 (pci-dda02/16)
20  * Author: Ivan Martinez <ivanmr@altavista.com>
21  *	   Frank Mori Hess <fmhess@users.sourceforge.net>
22  * Status: works
23  *
24  * Configuration options: not applicable, uses PCI auto config
25  *
26  * Only simple analog output writing is supported.
27  */
28 
29 #include <linux/module.h>
30 #include <linux/comedi/comedi_pci.h>
31 #include <linux/comedi/comedi_8255.h>
32 
33 #define EEPROM_SIZE	128	/*  number of entries in eeprom */
34 /* maximum number of ao channels for supported boards */
35 #define MAX_AO_CHANNELS 8
36 
37 /* Digital I/O registers */
38 #define CB_DDA_DIO0_8255_BASE		0x00
39 #define CB_DDA_DIO1_8255_BASE		0x04
40 
41 /* DAC registers */
42 #define CB_DDA_DA_CTRL_REG		0x00	   /* D/A Control Register  */
43 #define CB_DDA_DA_CTRL_SU		BIT(0)   /*  Simultaneous update  */
44 #define CB_DDA_DA_CTRL_EN		BIT(1)   /*  Enable specified DAC */
45 #define CB_DDA_DA_CTRL_DAC(x)		((x) << 2) /*  Specify DAC channel  */
46 #define CB_DDA_DA_CTRL_RANGE2V5		(0 << 6)   /*  2.5V range           */
47 #define CB_DDA_DA_CTRL_RANGE5V		(2 << 6)   /*  5V range             */
48 #define CB_DDA_DA_CTRL_RANGE10V		(3 << 6)   /*  10V range            */
49 #define CB_DDA_DA_CTRL_UNIP		BIT(8)   /*  Unipolar range       */
50 
51 #define DACALIBRATION1	4	/*  D/A CALIBRATION REGISTER 1 */
52 /* write bits */
53 /* serial data input for eeprom, caldacs, reference dac */
54 #define SERIAL_IN_BIT   0x1
55 #define	CAL_CHANNEL_MASK	(0x7 << 1)
56 #define	CAL_CHANNEL_BITS(channel)	(((channel) << 1) & CAL_CHANNEL_MASK)
57 /* read bits */
58 #define	CAL_COUNTER_MASK	0x1f
59 /* calibration counter overflow status bit */
60 #define CAL_COUNTER_OVERFLOW_BIT        0x20
61 /* analog output is less than reference dac voltage */
62 #define AO_BELOW_REF_BIT        0x40
63 #define	SERIAL_OUT_BIT	0x80	/*  serial data out, for reading from eeprom */
64 
65 #define DACALIBRATION2	6	/*  D/A CALIBRATION REGISTER 2 */
66 #define	SELECT_EEPROM_BIT	0x1	/*  send serial data in to eeprom */
67 /* don't send serial data to MAX542 reference dac */
68 #define DESELECT_REF_DAC_BIT    0x2
69 /* don't send serial data to caldac n */
70 #define DESELECT_CALDAC_BIT(n)  (0x4 << (n))
71 /* manual says to set this bit with no explanation */
72 #define DUMMY_BIT       0x40
73 
74 #define CB_DDA_DA_DATA_REG(x)		(0x08 + ((x) * 2))
75 
76 /* Offsets for the caldac channels */
77 #define CB_DDA_CALDAC_FINE_GAIN		0
78 #define CB_DDA_CALDAC_COURSE_GAIN	1
79 #define CB_DDA_CALDAC_COURSE_OFFSET	2
80 #define CB_DDA_CALDAC_FINE_OFFSET	3
81 
82 static const struct comedi_lrange cb_pcidda_ranges = {
83 	6, {
84 		BIP_RANGE(10),
85 		BIP_RANGE(5),
86 		BIP_RANGE(2.5),
87 		UNI_RANGE(10),
88 		UNI_RANGE(5),
89 		UNI_RANGE(2.5)
90 	}
91 };
92 
93 enum cb_pcidda_boardid {
94 	BOARD_DDA02_12,
95 	BOARD_DDA04_12,
96 	BOARD_DDA08_12,
97 	BOARD_DDA02_16,
98 	BOARD_DDA04_16,
99 	BOARD_DDA08_16,
100 };
101 
102 struct cb_pcidda_board {
103 	const char *name;
104 	int ao_chans;
105 	int ao_bits;
106 };
107 
108 static const struct cb_pcidda_board cb_pcidda_boards[] = {
109 	[BOARD_DDA02_12] = {
110 		.name		= "pci-dda02/12",
111 		.ao_chans	= 2,
112 		.ao_bits	= 12,
113 	},
114 	[BOARD_DDA04_12] = {
115 		.name		= "pci-dda04/12",
116 		.ao_chans	= 4,
117 		.ao_bits	= 12,
118 	},
119 	[BOARD_DDA08_12] = {
120 		.name		= "pci-dda08/12",
121 		.ao_chans	= 8,
122 		.ao_bits	= 12,
123 	},
124 	[BOARD_DDA02_16] = {
125 		.name		= "pci-dda02/16",
126 		.ao_chans	= 2,
127 		.ao_bits	= 16,
128 	},
129 	[BOARD_DDA04_16] = {
130 		.name		= "pci-dda04/16",
131 		.ao_chans	= 4,
132 		.ao_bits	= 16,
133 	},
134 	[BOARD_DDA08_16] = {
135 		.name		= "pci-dda08/16",
136 		.ao_chans	= 8,
137 		.ao_bits	= 16,
138 	},
139 };
140 
141 struct cb_pcidda_private {
142 	unsigned long daqio;
143 	/* bits last written to da calibration register 1 */
144 	unsigned int dac_cal1_bits;
145 	/* current range settings for output channels */
146 	unsigned int ao_range[MAX_AO_CHANNELS];
147 	u16 eeprom_data[EEPROM_SIZE];	/*  software copy of board's eeprom */
148 };
149 
150 /* lowlevel read from eeprom */
cb_pcidda_serial_in(struct comedi_device * dev)151 static unsigned int cb_pcidda_serial_in(struct comedi_device *dev)
152 {
153 	struct cb_pcidda_private *devpriv = dev->private;
154 	unsigned int value = 0;
155 	int i;
156 	const int value_width = 16;	/*  number of bits wide values are */
157 
158 	for (i = 1; i <= value_width; i++) {
159 		/*  read bits most significant bit first */
160 		if (inw_p(devpriv->daqio + DACALIBRATION1) & SERIAL_OUT_BIT)
161 			value |= 1 << (value_width - i);
162 	}
163 
164 	return value;
165 }
166 
167 /* lowlevel write to eeprom/dac */
cb_pcidda_serial_out(struct comedi_device * dev,unsigned int value,unsigned int num_bits)168 static void cb_pcidda_serial_out(struct comedi_device *dev, unsigned int value,
169 				 unsigned int num_bits)
170 {
171 	struct cb_pcidda_private *devpriv = dev->private;
172 	int i;
173 
174 	for (i = 1; i <= num_bits; i++) {
175 		/*  send bits most significant bit first */
176 		if (value & (1 << (num_bits - i)))
177 			devpriv->dac_cal1_bits |= SERIAL_IN_BIT;
178 		else
179 			devpriv->dac_cal1_bits &= ~SERIAL_IN_BIT;
180 		outw_p(devpriv->dac_cal1_bits, devpriv->daqio + DACALIBRATION1);
181 	}
182 }
183 
184 /* reads a 16 bit value from board's eeprom */
cb_pcidda_read_eeprom(struct comedi_device * dev,unsigned int address)185 static unsigned int cb_pcidda_read_eeprom(struct comedi_device *dev,
186 					  unsigned int address)
187 {
188 	struct cb_pcidda_private *devpriv = dev->private;
189 	unsigned int i;
190 	unsigned int cal2_bits;
191 	unsigned int value;
192 	/* one caldac for every two dac channels */
193 	const int max_num_caldacs = 4;
194 	/* bits to send to tell eeprom we want to read */
195 	const int read_instruction = 0x6;
196 	const int instruction_length = 3;
197 	const int address_length = 8;
198 
199 	/*  send serial output stream to eeprom */
200 	cal2_bits = SELECT_EEPROM_BIT | DESELECT_REF_DAC_BIT | DUMMY_BIT;
201 	/*  deactivate caldacs (one caldac for every two channels) */
202 	for (i = 0; i < max_num_caldacs; i++)
203 		cal2_bits |= DESELECT_CALDAC_BIT(i);
204 	outw_p(cal2_bits, devpriv->daqio + DACALIBRATION2);
205 
206 	/*  tell eeprom we want to read */
207 	cb_pcidda_serial_out(dev, read_instruction, instruction_length);
208 	/*  send address we want to read from */
209 	cb_pcidda_serial_out(dev, address, address_length);
210 
211 	value = cb_pcidda_serial_in(dev);
212 
213 	/*  deactivate eeprom */
214 	cal2_bits &= ~SELECT_EEPROM_BIT;
215 	outw_p(cal2_bits, devpriv->daqio + DACALIBRATION2);
216 
217 	return value;
218 }
219 
220 /* writes to 8 bit calibration dacs */
cb_pcidda_write_caldac(struct comedi_device * dev,unsigned int caldac,unsigned int channel,unsigned int value)221 static void cb_pcidda_write_caldac(struct comedi_device *dev,
222 				   unsigned int caldac, unsigned int channel,
223 				   unsigned int value)
224 {
225 	struct cb_pcidda_private *devpriv = dev->private;
226 	unsigned int cal2_bits;
227 	unsigned int i;
228 	/* caldacs use 3 bit channel specification */
229 	const int num_channel_bits = 3;
230 	const int num_caldac_bits = 8;	/*  8 bit calibration dacs */
231 	/* one caldac for every two dac channels */
232 	const int max_num_caldacs = 4;
233 
234 	/* write 3 bit channel */
235 	cb_pcidda_serial_out(dev, channel, num_channel_bits);
236 	/*  write 8 bit caldac value */
237 	cb_pcidda_serial_out(dev, value, num_caldac_bits);
238 
239 /*
240  * latch stream into appropriate caldac deselect reference dac
241  */
242 	cal2_bits = DESELECT_REF_DAC_BIT | DUMMY_BIT;
243 	/*  deactivate caldacs (one caldac for every two channels) */
244 	for (i = 0; i < max_num_caldacs; i++)
245 		cal2_bits |= DESELECT_CALDAC_BIT(i);
246 	/*  activate the caldac we want */
247 	cal2_bits &= ~DESELECT_CALDAC_BIT(caldac);
248 	outw_p(cal2_bits, devpriv->daqio + DACALIBRATION2);
249 	/*  deactivate caldac */
250 	cal2_bits |= DESELECT_CALDAC_BIT(caldac);
251 	outw_p(cal2_bits, devpriv->daqio + DACALIBRATION2);
252 }
253 
254 /* set caldacs to eeprom values for given channel and range */
cb_pcidda_calibrate(struct comedi_device * dev,unsigned int channel,unsigned int range)255 static void cb_pcidda_calibrate(struct comedi_device *dev, unsigned int channel,
256 				unsigned int range)
257 {
258 	struct cb_pcidda_private *devpriv = dev->private;
259 	unsigned int caldac = channel / 2;	/* two caldacs per channel */
260 	unsigned int chan = 4 * (channel % 2);	/* caldac channel base */
261 	unsigned int index = 2 * range + 12 * channel;
262 	unsigned int offset;
263 	unsigned int gain;
264 
265 	/* save range so we can tell when we need to readjust calibration */
266 	devpriv->ao_range[channel] = range;
267 
268 	/* get values from eeprom data */
269 	offset = devpriv->eeprom_data[0x7 + index];
270 	gain = devpriv->eeprom_data[0x8 + index];
271 
272 	/* set caldacs */
273 	cb_pcidda_write_caldac(dev, caldac, chan + CB_DDA_CALDAC_COURSE_OFFSET,
274 			       (offset >> 8) & 0xff);
275 	cb_pcidda_write_caldac(dev, caldac, chan + CB_DDA_CALDAC_FINE_OFFSET,
276 			       offset & 0xff);
277 	cb_pcidda_write_caldac(dev, caldac, chan + CB_DDA_CALDAC_COURSE_GAIN,
278 			       (gain >> 8) & 0xff);
279 	cb_pcidda_write_caldac(dev, caldac, chan + CB_DDA_CALDAC_FINE_GAIN,
280 			       gain & 0xff);
281 }
282 
cb_pcidda_ao_insn_write(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)283 static int cb_pcidda_ao_insn_write(struct comedi_device *dev,
284 				   struct comedi_subdevice *s,
285 				   struct comedi_insn *insn,
286 				   unsigned int *data)
287 {
288 	struct cb_pcidda_private *devpriv = dev->private;
289 	unsigned int channel = CR_CHAN(insn->chanspec);
290 	unsigned int range = CR_RANGE(insn->chanspec);
291 	unsigned int ctrl;
292 	unsigned int i;
293 
294 	if (range != devpriv->ao_range[channel])
295 		cb_pcidda_calibrate(dev, channel, range);
296 
297 	ctrl = CB_DDA_DA_CTRL_EN | CB_DDA_DA_CTRL_DAC(channel);
298 
299 	switch (range) {
300 	case 0:
301 	case 3:
302 		ctrl |= CB_DDA_DA_CTRL_RANGE10V;
303 		break;
304 	case 1:
305 	case 4:
306 		ctrl |= CB_DDA_DA_CTRL_RANGE5V;
307 		break;
308 	case 2:
309 	case 5:
310 		ctrl |= CB_DDA_DA_CTRL_RANGE2V5;
311 		break;
312 	}
313 
314 	if (range > 2)
315 		ctrl |= CB_DDA_DA_CTRL_UNIP;
316 
317 	outw(ctrl, devpriv->daqio + CB_DDA_DA_CTRL_REG);
318 
319 	for (i = 0; i < insn->n; i++)
320 		outw(data[i], devpriv->daqio + CB_DDA_DA_DATA_REG(channel));
321 
322 	return insn->n;
323 }
324 
cb_pcidda_auto_attach(struct comedi_device * dev,unsigned long context)325 static int cb_pcidda_auto_attach(struct comedi_device *dev,
326 				 unsigned long context)
327 {
328 	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
329 	const struct cb_pcidda_board *board = NULL;
330 	struct cb_pcidda_private *devpriv;
331 	struct comedi_subdevice *s;
332 	int i;
333 	int ret;
334 
335 	if (context < ARRAY_SIZE(cb_pcidda_boards))
336 		board = &cb_pcidda_boards[context];
337 	if (!board)
338 		return -ENODEV;
339 	dev->board_ptr = board;
340 	dev->board_name = board->name;
341 
342 	devpriv = comedi_alloc_devpriv(dev, sizeof(*devpriv));
343 	if (!devpriv)
344 		return -ENOMEM;
345 
346 	ret = comedi_pci_enable(dev);
347 	if (ret)
348 		return ret;
349 	dev->iobase = pci_resource_start(pcidev, 2);
350 	devpriv->daqio = pci_resource_start(pcidev, 3);
351 
352 	ret = comedi_alloc_subdevices(dev, 3);
353 	if (ret)
354 		return ret;
355 
356 	s = &dev->subdevices[0];
357 	/* analog output subdevice */
358 	s->type = COMEDI_SUBD_AO;
359 	s->subdev_flags = SDF_WRITABLE;
360 	s->n_chan = board->ao_chans;
361 	s->maxdata = (1 << board->ao_bits) - 1;
362 	s->range_table = &cb_pcidda_ranges;
363 	s->insn_write = cb_pcidda_ao_insn_write;
364 
365 	/* two 8255 digital io subdevices */
366 	for (i = 0; i < 2; i++) {
367 		s = &dev->subdevices[1 + i];
368 		ret = subdev_8255_init(dev, s, NULL, i * I8255_SIZE);
369 		if (ret)
370 			return ret;
371 	}
372 
373 	/* Read the caldac eeprom data */
374 	for (i = 0; i < EEPROM_SIZE; i++)
375 		devpriv->eeprom_data[i] = cb_pcidda_read_eeprom(dev, i);
376 
377 	/*  set calibrations dacs */
378 	for (i = 0; i < board->ao_chans; i++)
379 		cb_pcidda_calibrate(dev, i, devpriv->ao_range[i]);
380 
381 	return 0;
382 }
383 
384 static struct comedi_driver cb_pcidda_driver = {
385 	.driver_name	= "cb_pcidda",
386 	.module		= THIS_MODULE,
387 	.auto_attach	= cb_pcidda_auto_attach,
388 	.detach		= comedi_pci_detach,
389 };
390 
cb_pcidda_pci_probe(struct pci_dev * dev,const struct pci_device_id * id)391 static int cb_pcidda_pci_probe(struct pci_dev *dev,
392 			       const struct pci_device_id *id)
393 {
394 	return comedi_pci_auto_config(dev, &cb_pcidda_driver,
395 				      id->driver_data);
396 }
397 
398 static const struct pci_device_id cb_pcidda_pci_table[] = {
399 	{ PCI_VDEVICE(CB, 0x0020), BOARD_DDA02_12 },
400 	{ PCI_VDEVICE(CB, 0x0021), BOARD_DDA04_12 },
401 	{ PCI_VDEVICE(CB, 0x0022), BOARD_DDA08_12 },
402 	{ PCI_VDEVICE(CB, 0x0023), BOARD_DDA02_16 },
403 	{ PCI_VDEVICE(CB, 0x0024), BOARD_DDA04_16 },
404 	{ PCI_VDEVICE(CB, 0x0025), BOARD_DDA08_16 },
405 	{ 0 }
406 };
407 MODULE_DEVICE_TABLE(pci, cb_pcidda_pci_table);
408 
409 static struct pci_driver cb_pcidda_pci_driver = {
410 	.name		= "cb_pcidda",
411 	.id_table	= cb_pcidda_pci_table,
412 	.probe		= cb_pcidda_pci_probe,
413 	.remove		= comedi_pci_auto_unconfig,
414 };
415 module_comedi_pci_driver(cb_pcidda_driver, cb_pcidda_pci_driver);
416 
417 MODULE_AUTHOR("Comedi https://www.comedi.org");
418 MODULE_DESCRIPTION("Comedi low-level driver");
419 MODULE_LICENSE("GPL");
420