1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Command support for NI general purpose counters
4 *
5 * Copyright (C) 2006 Frank Mori Hess <fmhess@users.sourceforge.net>
6 */
7
8/*
9 * Module: ni_tiocmd
10 * Description: National Instruments general purpose counters command support
11 * Author: J.P. Mellor <jpmellor@rose-hulman.edu>,
12 *         Herman.Bruyninckx@mech.kuleuven.ac.be,
13 *         Wim.Meeussen@mech.kuleuven.ac.be,
14 *         Klaas.Gadeyne@mech.kuleuven.ac.be,
15 *         Frank Mori Hess <fmhess@users.sourceforge.net>
16 * Updated: Fri, 11 Apr 2008 12:32:35 +0100
17 * Status: works
18 *
19 * This module is not used directly by end-users.  Rather, it
20 * is used by other drivers (for example ni_660x and ni_pcimio)
21 * to provide command support for NI's general purpose counters.
22 * It was originally split out of ni_tio.c to stop the 'ni_tio'
23 * module depending on the 'mite' module.
24 *
25 * References:
26 * DAQ 660x Register-Level Programmer Manual  (NI 370505A-01)
27 * DAQ 6601/6602 User Manual (NI 322137B-01)
28 * 340934b.pdf  DAQ-STC reference manual
29 *
30 * TODO: Support use of both banks X and Y
31 */
32
33#include <linux/module.h>
34#include "ni_tio_internal.h"
35#include "mite.h"
36#include "ni_routes.h"
37
38static void ni_tio_configure_dma(struct ni_gpct *counter,
39				 bool enable, bool read)
40{
41	struct ni_gpct_device *counter_dev = counter->counter_dev;
42	unsigned int cidx = counter->counter_index;
43	unsigned int mask;
44	unsigned int bits;
45
46	mask = GI_READ_ACKS_IRQ | GI_WRITE_ACKS_IRQ;
47	bits = 0;
48
49	if (enable) {
50		if (read)
51			bits |= GI_READ_ACKS_IRQ;
52		else
53			bits |= GI_WRITE_ACKS_IRQ;
54	}
55	ni_tio_set_bits(counter, NITIO_INPUT_SEL_REG(cidx), mask, bits);
56
57	switch (counter_dev->variant) {
58	case ni_gpct_variant_e_series:
59		break;
60	case ni_gpct_variant_m_series:
61	case ni_gpct_variant_660x:
62		mask = GI_DMA_ENABLE | GI_DMA_INT_ENA | GI_DMA_WRITE;
63		bits = 0;
64
65		if (enable)
66			bits |= GI_DMA_ENABLE | GI_DMA_INT_ENA;
67		if (!read)
68			bits |= GI_DMA_WRITE;
69		ni_tio_set_bits(counter, NITIO_DMA_CFG_REG(cidx), mask, bits);
70		break;
71	}
72}
73
74static int ni_tio_input_inttrig(struct comedi_device *dev,
75				struct comedi_subdevice *s,
76				unsigned int trig_num)
77{
78	struct ni_gpct *counter = s->private;
79	struct comedi_cmd *cmd = &s->async->cmd;
80	unsigned long flags;
81	int ret = 0;
82
83	if (trig_num != cmd->start_arg)
84		return -EINVAL;
85
86	spin_lock_irqsave(&counter->lock, flags);
87	if (counter->mite_chan)
88		mite_dma_arm(counter->mite_chan);
89	else
90		ret = -EIO;
91	spin_unlock_irqrestore(&counter->lock, flags);
92	if (ret < 0)
93		return ret;
94	ret = ni_tio_arm(counter, true, NI_GPCT_ARM_IMMEDIATE);
95	s->async->inttrig = NULL;
96
97	return ret;
98}
99
100static int ni_tio_input_cmd(struct comedi_subdevice *s)
101{
102	struct ni_gpct *counter = s->private;
103	struct ni_gpct_device *counter_dev = counter->counter_dev;
104	const struct ni_route_tables *routing_tables =
105		counter_dev->routing_tables;
106	unsigned int cidx = counter->counter_index;
107	struct comedi_async *async = s->async;
108	struct comedi_cmd *cmd = &async->cmd;
109	int ret = 0;
110
111	/* write alloc the entire buffer */
112	comedi_buf_write_alloc(s, async->prealloc_bufsz);
113	counter->mite_chan->dir = COMEDI_INPUT;
114	switch (counter_dev->variant) {
115	case ni_gpct_variant_m_series:
116	case ni_gpct_variant_660x:
117		mite_prep_dma(counter->mite_chan, 32, 32);
118		break;
119	case ni_gpct_variant_e_series:
120		mite_prep_dma(counter->mite_chan, 16, 32);
121		break;
122	}
123	ni_tio_set_bits(counter, NITIO_CMD_REG(cidx), GI_SAVE_TRACE, 0);
124	ni_tio_configure_dma(counter, true, true);
125
126	if (cmd->start_src == TRIG_INT) {
127		async->inttrig = &ni_tio_input_inttrig;
128	} else {	/* TRIG_NOW || TRIG_EXT || TRIG_OTHER */
129		async->inttrig = NULL;
130		mite_dma_arm(counter->mite_chan);
131
132		if (cmd->start_src == TRIG_NOW)
133			ret = ni_tio_arm(counter, true, NI_GPCT_ARM_IMMEDIATE);
134		else if (cmd->start_src == TRIG_EXT) {
135			int reg = CR_CHAN(cmd->start_arg);
136
137			if (reg >= NI_NAMES_BASE) {
138				/* using a device-global name. lookup reg */
139				reg = ni_get_reg_value(reg,
140						       NI_CtrArmStartTrigger(cidx),
141						       routing_tables);
142				/* mark this as a raw register value */
143				reg |= NI_GPCT_HW_ARM;
144			}
145			ret = ni_tio_arm(counter, true, reg);
146		}
147	}
148	return ret;
149}
150
151static int ni_tio_output_cmd(struct comedi_subdevice *s)
152{
153	struct ni_gpct *counter = s->private;
154
155	dev_err(counter->counter_dev->dev->class_dev,
156		"output commands not yet implemented.\n");
157	return -ENOTSUPP;
158}
159
160static int ni_tio_cmd_setup(struct comedi_subdevice *s)
161{
162	struct comedi_cmd *cmd = &s->async->cmd;
163	struct ni_gpct *counter = s->private;
164	unsigned int cidx = counter->counter_index;
165	const struct ni_route_tables *routing_tables =
166		counter->counter_dev->routing_tables;
167	int set_gate_source = 0;
168	unsigned int gate_source;
169	int retval = 0;
170
171	if (cmd->scan_begin_src == TRIG_EXT) {
172		set_gate_source = 1;
173		gate_source = cmd->scan_begin_arg;
174	} else if (cmd->convert_src == TRIG_EXT) {
175		set_gate_source = 1;
176		gate_source = cmd->convert_arg;
177	}
178	if (set_gate_source) {
179		if (CR_CHAN(gate_source) >= NI_NAMES_BASE) {
180			/* Lookup and use the real register values */
181			int reg = ni_get_reg_value(CR_CHAN(gate_source),
182						   NI_CtrGate(cidx),
183						   routing_tables);
184			if (reg < 0)
185				return -EINVAL;
186			retval = ni_tio_set_gate_src_raw(counter, 0, reg);
187		} else {
188			/*
189			 * This function must be used separately since it does
190			 * not expect real register values and attempts to
191			 * convert these to real register values.
192			 */
193			retval = ni_tio_set_gate_src(counter, 0, gate_source);
194		}
195	}
196	if (cmd->flags & CMDF_WAKE_EOS) {
197		ni_tio_set_bits(counter, NITIO_INT_ENA_REG(cidx),
198				GI_GATE_INTERRUPT_ENABLE(cidx),
199				GI_GATE_INTERRUPT_ENABLE(cidx));
200	}
201	return retval;
202}
203
204int ni_tio_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
205{
206	struct ni_gpct *counter = s->private;
207	struct comedi_async *async = s->async;
208	struct comedi_cmd *cmd = &async->cmd;
209	int retval = 0;
210	unsigned long flags;
211
212	spin_lock_irqsave(&counter->lock, flags);
213	if (!counter->mite_chan) {
214		dev_err(counter->counter_dev->dev->class_dev,
215			"commands only supported with DMA.  ");
216		dev_err(counter->counter_dev->dev->class_dev,
217			"Interrupt-driven commands not yet implemented.\n");
218		retval = -EIO;
219	} else {
220		retval = ni_tio_cmd_setup(s);
221		if (retval == 0) {
222			if (cmd->flags & CMDF_WRITE)
223				retval = ni_tio_output_cmd(s);
224			else
225				retval = ni_tio_input_cmd(s);
226		}
227	}
228	spin_unlock_irqrestore(&counter->lock, flags);
229	return retval;
230}
231EXPORT_SYMBOL_GPL(ni_tio_cmd);
232
233int ni_tio_cmdtest(struct comedi_device *dev,
234		   struct comedi_subdevice *s,
235		   struct comedi_cmd *cmd)
236{
237	struct ni_gpct *counter = s->private;
238	unsigned int cidx = counter->counter_index;
239	const struct ni_route_tables *routing_tables =
240		counter->counter_dev->routing_tables;
241	int err = 0;
242	unsigned int sources;
243
244	/* Step 1 : check if triggers are trivially valid */
245
246	sources = TRIG_NOW | TRIG_INT | TRIG_OTHER;
247	if (ni_tio_counting_mode_registers_present(counter->counter_dev))
248		sources |= TRIG_EXT;
249	err |= comedi_check_trigger_src(&cmd->start_src, sources);
250
251	err |= comedi_check_trigger_src(&cmd->scan_begin_src,
252					TRIG_FOLLOW | TRIG_EXT | TRIG_OTHER);
253	err |= comedi_check_trigger_src(&cmd->convert_src,
254					TRIG_NOW | TRIG_EXT | TRIG_OTHER);
255	err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
256	err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_NONE);
257
258	if (err)
259		return 1;
260
261	/* Step 2a : make sure trigger sources are unique */
262
263	err |= comedi_check_trigger_is_unique(cmd->start_src);
264	err |= comedi_check_trigger_is_unique(cmd->scan_begin_src);
265	err |= comedi_check_trigger_is_unique(cmd->convert_src);
266
267	/* Step 2b : and mutually compatible */
268
269	if (cmd->convert_src != TRIG_NOW && cmd->scan_begin_src != TRIG_FOLLOW)
270		err |= -EINVAL;
271
272	if (err)
273		return 2;
274
275	/* Step 3: check if arguments are trivially valid */
276
277	switch (cmd->start_src) {
278	case TRIG_NOW:
279	case TRIG_INT:
280	case TRIG_OTHER:
281		err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
282		break;
283	case TRIG_EXT:
284		/* start_arg is the start_trigger passed to ni_tio_arm() */
285		/*
286		 * This should be done, but we don't yet know the actual
287		 * register values.  These should be tested and then documented
288		 * in the ni_route_values/ni_*.csv files, with indication of
289		 * who/when/which/how these were tested.
290		 * When at least a e/m/660x series have been tested, this code
291		 * should be uncommented:
292		 *
293		 * err |= ni_check_trigger_arg(CR_CHAN(cmd->start_arg),
294		 *			    NI_CtrArmStartTrigger(cidx),
295		 *			    routing_tables);
296		 */
297		break;
298	}
299
300	/*
301	 * It seems that convention is to allow either scan_begin_arg or
302	 * convert_arg to specify the Gate source, with scan_begin_arg taking
303	 * precedence.
304	 */
305	if (cmd->scan_begin_src != TRIG_EXT)
306		err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
307	else
308		err |= ni_check_trigger_arg(CR_CHAN(cmd->scan_begin_arg),
309					    NI_CtrGate(cidx), routing_tables);
310
311	if (cmd->convert_src != TRIG_EXT)
312		err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
313	else
314		err |= ni_check_trigger_arg(CR_CHAN(cmd->convert_arg),
315					    NI_CtrGate(cidx), routing_tables);
316
317	err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
318					   cmd->chanlist_len);
319	err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
320
321	if (err)
322		return 3;
323
324	/* Step 4: fix up any arguments */
325
326	/* Step 5: check channel list if it exists */
327
328	return 0;
329}
330EXPORT_SYMBOL_GPL(ni_tio_cmdtest);
331
332int ni_tio_cancel(struct ni_gpct *counter)
333{
334	unsigned int cidx = counter->counter_index;
335	unsigned long flags;
336
337	ni_tio_arm(counter, false, 0);
338	spin_lock_irqsave(&counter->lock, flags);
339	if (counter->mite_chan)
340		mite_dma_disarm(counter->mite_chan);
341	spin_unlock_irqrestore(&counter->lock, flags);
342	ni_tio_configure_dma(counter, false, false);
343
344	ni_tio_set_bits(counter, NITIO_INT_ENA_REG(cidx),
345			GI_GATE_INTERRUPT_ENABLE(cidx), 0x0);
346	return 0;
347}
348EXPORT_SYMBOL_GPL(ni_tio_cancel);
349
350static int should_ack_gate(struct ni_gpct *counter)
351{
352	unsigned long flags;
353	int retval = 0;
354
355	switch (counter->counter_dev->variant) {
356	case ni_gpct_variant_m_series:
357	case ni_gpct_variant_660x:
358		/*
359		 * not sure if 660x really supports gate interrupts
360		 * (the bits are not listed in register-level manual)
361		 */
362		return 1;
363	case ni_gpct_variant_e_series:
364		/*
365		 * During buffered input counter operation for e-series,
366		 * the gate interrupt is acked automatically by the dma
367		 * controller, due to the Gi_Read/Write_Acknowledges_IRQ
368		 * bits in the input select register.
369		 */
370		spin_lock_irqsave(&counter->lock, flags);
371		{
372			if (!counter->mite_chan ||
373			    counter->mite_chan->dir != COMEDI_INPUT ||
374			    (mite_done(counter->mite_chan))) {
375				retval = 1;
376			}
377		}
378		spin_unlock_irqrestore(&counter->lock, flags);
379		break;
380	}
381	return retval;
382}
383
384static void ni_tio_acknowledge_and_confirm(struct ni_gpct *counter,
385					   int *gate_error,
386					   int *tc_error,
387					   int *perm_stale_data)
388{
389	unsigned int cidx = counter->counter_index;
390	const unsigned short gxx_status = ni_tio_read(counter,
391						NITIO_SHARED_STATUS_REG(cidx));
392	const unsigned short gi_status = ni_tio_read(counter,
393						NITIO_STATUS_REG(cidx));
394	unsigned int ack = 0;
395
396	if (gate_error)
397		*gate_error = 0;
398	if (tc_error)
399		*tc_error = 0;
400	if (perm_stale_data)
401		*perm_stale_data = 0;
402
403	if (gxx_status & GI_GATE_ERROR(cidx)) {
404		ack |= GI_GATE_ERROR_CONFIRM(cidx);
405		if (gate_error) {
406			/*
407			 * 660x don't support automatic acknowledgment
408			 * of gate interrupt via dma read/write
409			 * and report bogus gate errors
410			 */
411			if (counter->counter_dev->variant !=
412			    ni_gpct_variant_660x)
413				*gate_error = 1;
414		}
415	}
416	if (gxx_status & GI_TC_ERROR(cidx)) {
417		ack |= GI_TC_ERROR_CONFIRM(cidx);
418		if (tc_error)
419			*tc_error = 1;
420	}
421	if (gi_status & GI_TC)
422		ack |= GI_TC_INTERRUPT_ACK;
423	if (gi_status & GI_GATE_INTERRUPT) {
424		if (should_ack_gate(counter))
425			ack |= GI_GATE_INTERRUPT_ACK;
426	}
427	if (ack)
428		ni_tio_write(counter, ack, NITIO_INT_ACK_REG(cidx));
429	if (ni_tio_get_soft_copy(counter, NITIO_MODE_REG(cidx)) &
430	    GI_LOADING_ON_GATE) {
431		if (ni_tio_read(counter, NITIO_STATUS2_REG(cidx)) &
432		    GI_PERMANENT_STALE(cidx)) {
433			dev_info(counter->counter_dev->dev->class_dev,
434				 "%s: Gi_Permanent_Stale_Data detected.\n",
435				 __func__);
436			if (perm_stale_data)
437				*perm_stale_data = 1;
438		}
439	}
440}
441
442void ni_tio_acknowledge(struct ni_gpct *counter)
443{
444	ni_tio_acknowledge_and_confirm(counter, NULL, NULL, NULL);
445}
446EXPORT_SYMBOL_GPL(ni_tio_acknowledge);
447
448void ni_tio_handle_interrupt(struct ni_gpct *counter,
449			     struct comedi_subdevice *s)
450{
451	unsigned int cidx = counter->counter_index;
452	unsigned long flags;
453	int gate_error;
454	int tc_error;
455	int perm_stale_data;
456
457	ni_tio_acknowledge_and_confirm(counter, &gate_error, &tc_error,
458				       &perm_stale_data);
459	if (gate_error) {
460		dev_notice(counter->counter_dev->dev->class_dev,
461			   "%s: Gi_Gate_Error detected.\n", __func__);
462		s->async->events |= COMEDI_CB_OVERFLOW;
463	}
464	if (perm_stale_data)
465		s->async->events |= COMEDI_CB_ERROR;
466	switch (counter->counter_dev->variant) {
467	case ni_gpct_variant_m_series:
468	case ni_gpct_variant_660x:
469		if (ni_tio_read(counter, NITIO_DMA_STATUS_REG(cidx)) &
470		    GI_DRQ_ERROR) {
471			dev_notice(counter->counter_dev->dev->class_dev,
472				   "%s: Gi_DRQ_Error detected.\n", __func__);
473			s->async->events |= COMEDI_CB_OVERFLOW;
474		}
475		break;
476	case ni_gpct_variant_e_series:
477		break;
478	}
479	spin_lock_irqsave(&counter->lock, flags);
480	if (counter->mite_chan)
481		mite_ack_linkc(counter->mite_chan, s, true);
482	spin_unlock_irqrestore(&counter->lock, flags);
483}
484EXPORT_SYMBOL_GPL(ni_tio_handle_interrupt);
485
486void ni_tio_set_mite_channel(struct ni_gpct *counter,
487			     struct mite_channel *mite_chan)
488{
489	unsigned long flags;
490
491	spin_lock_irqsave(&counter->lock, flags);
492	counter->mite_chan = mite_chan;
493	spin_unlock_irqrestore(&counter->lock, flags);
494}
495EXPORT_SYMBOL_GPL(ni_tio_set_mite_channel);
496
497static int __init ni_tiocmd_init_module(void)
498{
499	return 0;
500}
501module_init(ni_tiocmd_init_module);
502
503static void __exit ni_tiocmd_cleanup_module(void)
504{
505}
506module_exit(ni_tiocmd_cleanup_module);
507
508MODULE_AUTHOR("Comedi <comedi@comedi.org>");
509MODULE_DESCRIPTION("Comedi command support for NI general-purpose counters");
510MODULE_LICENSE("GPL");
511