xref: /freebsd-13-stable/sys/arm/ti/ti_adc.c (revision 3bc80996974a61a4223eae4c1ccd47b6ee32a48a)
1 /*-
2  * Copyright 2014 Luiz Otavio O Souza <loos@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 #include "opt_evdev.h"
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/bus.h>
33 
34 #include <sys/conf.h>
35 #include <sys/kernel.h>
36 #include <sys/limits.h>
37 #include <sys/lock.h>
38 #include <sys/module.h>
39 #include <sys/mutex.h>
40 #include <sys/condvar.h>
41 #include <sys/resource.h>
42 #include <sys/rman.h>
43 #include <sys/sysctl.h>
44 #include <sys/selinfo.h>
45 #include <sys/poll.h>
46 #include <sys/uio.h>
47 
48 #include <machine/bus.h>
49 
50 #include <dev/ofw/openfirm.h>
51 #include <dev/ofw/ofw_bus.h>
52 #include <dev/ofw/ofw_bus_subr.h>
53 
54 #ifdef EVDEV_SUPPORT
55 #include <dev/evdev/input.h>
56 #include <dev/evdev/evdev.h>
57 #endif
58 
59 #include <arm/ti/ti_sysc.h>
60 #include <arm/ti/ti_adcreg.h>
61 #include <arm/ti/ti_adcvar.h>
62 
63 #undef	DEBUG_TSC
64 
65 #define	DEFAULT_CHARGE_DELAY	0x400
66 #define	STEPDLY_OPEN		0x98
67 
68 #define	ORDER_XP	0
69 #define	ORDER_XN	1
70 #define	ORDER_YP	2
71 #define	ORDER_YN	3
72 
73 /* Define our 8 steps, one for each input channel. */
74 static struct ti_adc_input ti_adc_inputs[TI_ADC_NPINS] = {
75 	{ .stepconfig = ADC_STEPCFG(1), .stepdelay = ADC_STEPDLY(1) },
76 	{ .stepconfig = ADC_STEPCFG(2), .stepdelay = ADC_STEPDLY(2) },
77 	{ .stepconfig = ADC_STEPCFG(3), .stepdelay = ADC_STEPDLY(3) },
78 	{ .stepconfig = ADC_STEPCFG(4), .stepdelay = ADC_STEPDLY(4) },
79 	{ .stepconfig = ADC_STEPCFG(5), .stepdelay = ADC_STEPDLY(5) },
80 	{ .stepconfig = ADC_STEPCFG(6), .stepdelay = ADC_STEPDLY(6) },
81 	{ .stepconfig = ADC_STEPCFG(7), .stepdelay = ADC_STEPDLY(7) },
82 	{ .stepconfig = ADC_STEPCFG(8), .stepdelay = ADC_STEPDLY(8) },
83 };
84 
85 static int ti_adc_samples[5] = { 0, 2, 4, 8, 16 };
86 
87 static int ti_adc_detach(device_t dev);
88 
89 #ifdef EVDEV_SUPPORT
90 static void
ti_adc_ev_report(struct ti_adc_softc * sc)91 ti_adc_ev_report(struct ti_adc_softc *sc)
92 {
93 
94 	evdev_push_event(sc->sc_evdev, EV_ABS, ABS_X, sc->sc_x);
95 	evdev_push_event(sc->sc_evdev, EV_ABS, ABS_Y, sc->sc_y);
96 	evdev_push_event(sc->sc_evdev, EV_KEY, BTN_TOUCH, sc->sc_pen_down);
97 	evdev_sync(sc->sc_evdev);
98 }
99 #endif /* EVDEV */
100 
101 static void
ti_adc_enable(struct ti_adc_softc * sc)102 ti_adc_enable(struct ti_adc_softc *sc)
103 {
104 	uint32_t reg;
105 
106 	TI_ADC_LOCK_ASSERT(sc);
107 
108 	if (sc->sc_last_state == 1)
109 		return;
110 
111 	/* Enable the FIFO0 threshold and the end of sequence interrupt. */
112 	ADC_WRITE4(sc, ADC_IRQENABLE_SET,
113 	    ADC_IRQ_FIFO0_THRES | ADC_IRQ_FIFO1_THRES | ADC_IRQ_END_OF_SEQ);
114 
115 	reg = ADC_CTRL_STEP_WP | ADC_CTRL_STEP_ID;
116 	if (sc->sc_tsc_wires > 0) {
117 		reg |= ADC_CTRL_TSC_ENABLE;
118 		switch (sc->sc_tsc_wires) {
119 		case 4:
120 			reg |= ADC_CTRL_TSC_4WIRE;
121 			break;
122 		case 5:
123 			reg |= ADC_CTRL_TSC_5WIRE;
124 			break;
125 		case 8:
126 			reg |= ADC_CTRL_TSC_8WIRE;
127 			break;
128 		default:
129 			break;
130 		}
131 	}
132 	reg |= ADC_CTRL_ENABLE;
133 	/* Enable the ADC.  Run thru enabled steps, start the conversions. */
134 	ADC_WRITE4(sc, ADC_CTRL, reg);
135 
136 	sc->sc_last_state = 1;
137 }
138 
139 static void
ti_adc_disable(struct ti_adc_softc * sc)140 ti_adc_disable(struct ti_adc_softc *sc)
141 {
142 	int count;
143 	uint32_t data;
144 
145 	TI_ADC_LOCK_ASSERT(sc);
146 
147 	if (sc->sc_last_state == 0)
148 		return;
149 
150 	/* Disable all the enabled steps. */
151 	ADC_WRITE4(sc, ADC_STEPENABLE, 0);
152 
153 	/* Disable the ADC. */
154 	ADC_WRITE4(sc, ADC_CTRL, ADC_READ4(sc, ADC_CTRL) & ~ADC_CTRL_ENABLE);
155 
156 	/* Disable the FIFO0 threshold and the end of sequence interrupt. */
157 	ADC_WRITE4(sc, ADC_IRQENABLE_CLR,
158 	    ADC_IRQ_FIFO0_THRES | ADC_IRQ_FIFO1_THRES | ADC_IRQ_END_OF_SEQ);
159 
160 	/* ACK any pending interrupt. */
161 	ADC_WRITE4(sc, ADC_IRQSTATUS, ADC_READ4(sc, ADC_IRQSTATUS));
162 
163 	/* Drain the FIFO data. */
164 	count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
165 	while (count > 0) {
166 		data = ADC_READ4(sc, ADC_FIFO0DATA);
167 		count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
168 	}
169 
170 	count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
171 	while (count > 0) {
172 		data = ADC_READ4(sc, ADC_FIFO1DATA);
173 		count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
174 	}
175 
176 	sc->sc_last_state = 0;
177 }
178 
179 static int
ti_adc_setup(struct ti_adc_softc * sc)180 ti_adc_setup(struct ti_adc_softc *sc)
181 {
182 	int ain, i;
183 	uint32_t enabled;
184 
185 	TI_ADC_LOCK_ASSERT(sc);
186 
187 	/* Check for enabled inputs. */
188 	enabled = sc->sc_tsc_enabled;
189 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
190 		ain = sc->sc_adc_channels[i];
191 		if (ti_adc_inputs[ain].enable)
192 			enabled |= (1U << (ain + 1));
193 	}
194 
195 	/* Set the ADC global status. */
196 	if (enabled != 0) {
197 		ti_adc_enable(sc);
198 		/* Update the enabled steps. */
199 		if (enabled != ADC_READ4(sc, ADC_STEPENABLE))
200 			ADC_WRITE4(sc, ADC_STEPENABLE, enabled);
201 	} else
202 		ti_adc_disable(sc);
203 
204 	return (0);
205 }
206 
207 static void
ti_adc_input_setup(struct ti_adc_softc * sc,int32_t ain)208 ti_adc_input_setup(struct ti_adc_softc *sc, int32_t ain)
209 {
210 	struct ti_adc_input *input;
211 	uint32_t reg, val;
212 
213 	TI_ADC_LOCK_ASSERT(sc);
214 
215 	input = &ti_adc_inputs[ain];
216 	reg = input->stepconfig;
217 	val = ADC_READ4(sc, reg);
218 
219 	/* Set single ended operation. */
220 	val &= ~ADC_STEP_DIFF_CNTRL;
221 
222 	/* Set the negative voltage reference. */
223 	val &= ~ADC_STEP_RFM_MSK;
224 
225 	/* Set the positive voltage reference. */
226 	val &= ~ADC_STEP_RFP_MSK;
227 
228 	/* Set the samples average. */
229 	val &= ~ADC_STEP_AVG_MSK;
230 	val |= input->samples << ADC_STEP_AVG_SHIFT;
231 
232 	/* Select the desired input. */
233 	val &= ~ADC_STEP_INP_MSK;
234 	val |= ain << ADC_STEP_INP_SHIFT;
235 
236 	/* Set the ADC to one-shot mode. */
237 	val &= ~ADC_STEP_MODE_MSK;
238 
239 	ADC_WRITE4(sc, reg, val);
240 }
241 
242 static void
ti_adc_reset(struct ti_adc_softc * sc)243 ti_adc_reset(struct ti_adc_softc *sc)
244 {
245 	int ain, i;
246 
247 	TI_ADC_LOCK_ASSERT(sc);
248 
249 	/* Disable all the inputs. */
250 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
251 		ain = sc->sc_adc_channels[i];
252 		ti_adc_inputs[ain].enable = 0;
253 	}
254 }
255 
256 static int
ti_adc_clockdiv_proc(SYSCTL_HANDLER_ARGS)257 ti_adc_clockdiv_proc(SYSCTL_HANDLER_ARGS)
258 {
259 	int error, reg;
260 	struct ti_adc_softc *sc;
261 
262 	sc = (struct ti_adc_softc *)arg1;
263 
264 	TI_ADC_LOCK(sc);
265 	reg = (int)ADC_READ4(sc, ADC_CLKDIV) + 1;
266 	TI_ADC_UNLOCK(sc);
267 
268 	error = sysctl_handle_int(oidp, &reg, sizeof(reg), req);
269 	if (error != 0 || req->newptr == NULL)
270 		return (error);
271 
272 	/*
273 	 * The actual written value is the prescaler setting - 1.
274 	 * Enforce a minimum value of 10 (i.e. 9) which limits the maximum
275 	 * ADC clock to ~2.4Mhz (CLK_M_OSC / 10).
276 	 */
277 	reg--;
278 	if (reg < 9)
279 		reg = 9;
280 	if (reg > USHRT_MAX)
281 		reg = USHRT_MAX;
282 
283 	TI_ADC_LOCK(sc);
284 	/* Disable the ADC. */
285 	ti_adc_disable(sc);
286 	/* Update the ADC prescaler setting. */
287 	ADC_WRITE4(sc, ADC_CLKDIV, reg);
288 	/* Enable the ADC again. */
289 	ti_adc_setup(sc);
290 	TI_ADC_UNLOCK(sc);
291 
292 	return (0);
293 }
294 
295 static int
ti_adc_enable_proc(SYSCTL_HANDLER_ARGS)296 ti_adc_enable_proc(SYSCTL_HANDLER_ARGS)
297 {
298 	int error;
299 	int32_t enable;
300 	struct ti_adc_softc *sc;
301 	struct ti_adc_input *input;
302 
303 	input = (struct ti_adc_input *)arg1;
304 	sc = input->sc;
305 
306 	enable = input->enable;
307 	error = sysctl_handle_int(oidp, &enable, sizeof(enable),
308 	    req);
309 	if (error != 0 || req->newptr == NULL)
310 		return (error);
311 
312 	if (enable)
313 		enable = 1;
314 
315 	TI_ADC_LOCK(sc);
316 	/* Setup the ADC as needed. */
317 	if (input->enable != enable) {
318 		input->enable = enable;
319 		ti_adc_setup(sc);
320 		if (input->enable == 0)
321 			input->value = 0;
322 	}
323 	TI_ADC_UNLOCK(sc);
324 
325 	return (0);
326 }
327 
328 static int
ti_adc_open_delay_proc(SYSCTL_HANDLER_ARGS)329 ti_adc_open_delay_proc(SYSCTL_HANDLER_ARGS)
330 {
331 	int error, reg;
332 	struct ti_adc_softc *sc;
333 	struct ti_adc_input *input;
334 
335 	input = (struct ti_adc_input *)arg1;
336 	sc = input->sc;
337 
338 	TI_ADC_LOCK(sc);
339 	reg = (int)ADC_READ4(sc, input->stepdelay) & ADC_STEP_OPEN_DELAY;
340 	TI_ADC_UNLOCK(sc);
341 
342 	error = sysctl_handle_int(oidp, &reg, sizeof(reg), req);
343 	if (error != 0 || req->newptr == NULL)
344 		return (error);
345 
346 	if (reg < 0)
347 		reg = 0;
348 
349 	TI_ADC_LOCK(sc);
350 	ADC_WRITE4(sc, input->stepdelay, reg & ADC_STEP_OPEN_DELAY);
351 	TI_ADC_UNLOCK(sc);
352 
353 	return (0);
354 }
355 
356 static int
ti_adc_samples_avg_proc(SYSCTL_HANDLER_ARGS)357 ti_adc_samples_avg_proc(SYSCTL_HANDLER_ARGS)
358 {
359 	int error, samples, i;
360 	struct ti_adc_softc *sc;
361 	struct ti_adc_input *input;
362 
363 	input = (struct ti_adc_input *)arg1;
364 	sc = input->sc;
365 
366 	if (input->samples > nitems(ti_adc_samples))
367 		input->samples = nitems(ti_adc_samples);
368 	samples = ti_adc_samples[input->samples];
369 
370 	error = sysctl_handle_int(oidp, &samples, 0, req);
371 	if (error != 0 || req->newptr == NULL)
372 		return (error);
373 
374 	TI_ADC_LOCK(sc);
375 	if (samples != ti_adc_samples[input->samples]) {
376 		input->samples = 0;
377 		for (i = 0; i < nitems(ti_adc_samples); i++)
378 			if (samples >= ti_adc_samples[i])
379 				input->samples = i;
380 		ti_adc_input_setup(sc, input->input);
381 	}
382 	TI_ADC_UNLOCK(sc);
383 
384 	return (error);
385 }
386 
387 static void
ti_adc_read_data(struct ti_adc_softc * sc)388 ti_adc_read_data(struct ti_adc_softc *sc)
389 {
390 	int count, ain;
391 	struct ti_adc_input *input;
392 	uint32_t data;
393 
394 	TI_ADC_LOCK_ASSERT(sc);
395 
396 	/* Read the available data. */
397 	count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
398 	while (count > 0) {
399 		data = ADC_READ4(sc, ADC_FIFO0DATA);
400 		ain = (data & ADC_FIFO_STEP_ID_MSK) >> ADC_FIFO_STEP_ID_SHIFT;
401 		input = &ti_adc_inputs[ain];
402 		if (input->enable == 0)
403 			input->value = 0;
404 		else
405 			input->value = (int32_t)(data & ADC_FIFO_DATA_MSK);
406 		count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
407 	}
408 }
409 
410 static int
cmp_values(const void * a,const void * b)411 cmp_values(const void *a, const void *b)
412 {
413 	const uint32_t *v1, *v2;
414 	v1 = a;
415 	v2 = b;
416 	if (*v1 < *v2)
417 		return -1;
418 	if (*v1 > *v2)
419 		return 1;
420 
421 	return (0);
422 }
423 
424 static void
ti_adc_tsc_read_data(struct ti_adc_softc * sc)425 ti_adc_tsc_read_data(struct ti_adc_softc *sc)
426 {
427 	int count;
428 	uint32_t data[16];
429 	uint32_t x, y;
430 	int i, start, end;
431 
432 	TI_ADC_LOCK_ASSERT(sc);
433 
434 	/* Read the available data. */
435 	count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
436 	if (count == 0)
437 		return;
438 
439 	i = 0;
440 	while (count > 0) {
441 		data[i++] = ADC_READ4(sc, ADC_FIFO1DATA) & ADC_FIFO_DATA_MSK;
442 		count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
443 	}
444 
445 	if (sc->sc_coord_readouts > 3) {
446 		start = 1;
447 		end = sc->sc_coord_readouts - 1;
448 		qsort(data, sc->sc_coord_readouts,
449 			sizeof(data[0]), &cmp_values);
450 		qsort(&data[sc->sc_coord_readouts + 2],
451 			sc->sc_coord_readouts,
452 			sizeof(data[0]), &cmp_values);
453 	}
454 	else {
455 		start = 0;
456 		end = sc->sc_coord_readouts;
457 	}
458 
459 	x = y = 0;
460 	for (i = start; i < end; i++)
461 		y += data[i];
462 	y /= (end - start);
463 
464 	for (i = sc->sc_coord_readouts + 2 + start; i < sc->sc_coord_readouts + 2 + end; i++)
465 		x += data[i];
466 	x /= (end - start);
467 
468 #ifdef DEBUG_TSC
469 	device_printf(sc->sc_dev, "touchscreen x: %d, y: %d\n", x, y);
470 #endif
471 
472 #ifdef EVDEV_SUPPORT
473 	if ((sc->sc_x != x) || (sc->sc_y != y)) {
474 		sc->sc_x = x;
475 		sc->sc_y = y;
476 		ti_adc_ev_report(sc);
477 	}
478 #endif
479 }
480 
481 static void
ti_adc_intr_locked(struct ti_adc_softc * sc,uint32_t status)482 ti_adc_intr_locked(struct ti_adc_softc *sc, uint32_t status)
483 {
484 	/* Read the available data. */
485 	if (status & ADC_IRQ_FIFO0_THRES)
486 		ti_adc_read_data(sc);
487 }
488 
489 static void
ti_adc_tsc_intr_locked(struct ti_adc_softc * sc,uint32_t status)490 ti_adc_tsc_intr_locked(struct ti_adc_softc *sc, uint32_t status)
491 {
492 	/* Read the available data. */
493 	if (status & ADC_IRQ_FIFO1_THRES)
494 		ti_adc_tsc_read_data(sc);
495 
496 }
497 
498 static void
ti_adc_intr(void * arg)499 ti_adc_intr(void *arg)
500 {
501 	struct ti_adc_softc *sc;
502 	uint32_t status, rawstatus;
503 
504 	sc = (struct ti_adc_softc *)arg;
505 
506 	TI_ADC_LOCK(sc);
507 
508 	rawstatus = ADC_READ4(sc, ADC_IRQSTATUS_RAW);
509 	status = ADC_READ4(sc, ADC_IRQSTATUS);
510 
511 	if (rawstatus & ADC_IRQ_HW_PEN_ASYNC) {
512 		sc->sc_pen_down = 1;
513 		status |= ADC_IRQ_HW_PEN_ASYNC;
514 		ADC_WRITE4(sc, ADC_IRQENABLE_CLR,
515 			ADC_IRQ_HW_PEN_ASYNC);
516 #ifdef EVDEV_SUPPORT
517 		ti_adc_ev_report(sc);
518 #endif
519 	}
520 
521 	if (rawstatus & ADC_IRQ_PEN_UP) {
522 		sc->sc_pen_down = 0;
523 		status |= ADC_IRQ_PEN_UP;
524 #ifdef EVDEV_SUPPORT
525 		ti_adc_ev_report(sc);
526 #endif
527 	}
528 
529 	if (status & ADC_IRQ_FIFO0_THRES)
530 		ti_adc_intr_locked(sc, status);
531 
532 	if (status & ADC_IRQ_FIFO1_THRES)
533 		ti_adc_tsc_intr_locked(sc, status);
534 
535 	if (status) {
536 		/* ACK the interrupt. */
537 		ADC_WRITE4(sc, ADC_IRQSTATUS, status);
538 	}
539 
540 	/* Start the next conversion ? */
541 	if (status & ADC_IRQ_END_OF_SEQ)
542 		ti_adc_setup(sc);
543 
544 	TI_ADC_UNLOCK(sc);
545 }
546 
547 static void
ti_adc_sysctl_init(struct ti_adc_softc * sc)548 ti_adc_sysctl_init(struct ti_adc_softc *sc)
549 {
550 	char pinbuf[3];
551 	struct sysctl_ctx_list *ctx;
552 	struct sysctl_oid *tree_node, *inp_node, *inpN_node;
553 	struct sysctl_oid_list *tree, *inp_tree, *inpN_tree;
554 	int ain, i;
555 
556 	/*
557 	 * Add per-pin sysctl tree/handlers.
558 	 */
559 	ctx = device_get_sysctl_ctx(sc->sc_dev);
560 	tree_node = device_get_sysctl_tree(sc->sc_dev);
561 	tree = SYSCTL_CHILDREN(tree_node);
562 	SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "clockdiv",
563 	    CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_NEEDGIANT,  sc, 0,
564 	    ti_adc_clockdiv_proc, "IU", "ADC clock prescaler");
565 	inp_node = SYSCTL_ADD_NODE(ctx, tree, OID_AUTO, "ain",
566 	    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "ADC inputs");
567 	inp_tree = SYSCTL_CHILDREN(inp_node);
568 
569 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
570 		ain = sc->sc_adc_channels[i];
571 
572 		snprintf(pinbuf, sizeof(pinbuf), "%d", ain);
573 		inpN_node = SYSCTL_ADD_NODE(ctx, inp_tree, OID_AUTO, pinbuf,
574 		    CTLFLAG_RD | CTLFLAG_MPSAFE, NULL, "ADC input");
575 		inpN_tree = SYSCTL_CHILDREN(inpN_node);
576 
577 		SYSCTL_ADD_PROC(ctx, inpN_tree, OID_AUTO, "enable",
578 		    CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_NEEDGIANT,
579 		    &ti_adc_inputs[ain], 0,
580 		    ti_adc_enable_proc, "IU", "Enable ADC input");
581 		SYSCTL_ADD_PROC(ctx, inpN_tree, OID_AUTO, "open_delay",
582 		    CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_NEEDGIANT,
583 		    &ti_adc_inputs[ain], 0,
584 		    ti_adc_open_delay_proc, "IU", "ADC open delay");
585 		SYSCTL_ADD_PROC(ctx, inpN_tree, OID_AUTO, "samples_avg",
586 		    CTLFLAG_RW | CTLTYPE_UINT | CTLFLAG_NEEDGIANT,
587 		    &ti_adc_inputs[ain], 0,
588 		    ti_adc_samples_avg_proc, "IU", "ADC samples average");
589 		SYSCTL_ADD_INT(ctx, inpN_tree, OID_AUTO, "input",
590 		    CTLFLAG_RD, &ti_adc_inputs[ain].value, 0,
591 		    "Converted raw value for the ADC input");
592 	}
593 }
594 
595 static void
ti_adc_inputs_init(struct ti_adc_softc * sc)596 ti_adc_inputs_init(struct ti_adc_softc *sc)
597 {
598 	int ain, i;
599 	struct ti_adc_input *input;
600 
601 	TI_ADC_LOCK(sc);
602 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
603 		ain = sc->sc_adc_channels[i];
604 		input = &ti_adc_inputs[ain];
605 		input->sc = sc;
606 		input->input = ain;
607 		input->value = 0;
608 		input->enable = 0;
609 		input->samples = 0;
610 		ti_adc_input_setup(sc, ain);
611 	}
612 	TI_ADC_UNLOCK(sc);
613 }
614 
615 static void
ti_adc_tsc_init(struct ti_adc_softc * sc)616 ti_adc_tsc_init(struct ti_adc_softc *sc)
617 {
618 	int i, start_step, end_step;
619 	uint32_t stepconfig, val;
620 
621 	TI_ADC_LOCK(sc);
622 
623 	/* X coordinates */
624 	stepconfig = ADC_STEP_FIFO1 | (4 << ADC_STEP_AVG_SHIFT) |
625 	    ADC_STEP_MODE_HW_ONESHOT | sc->sc_xp_bit;
626 	if (sc->sc_tsc_wires == 4)
627 		stepconfig |= ADC_STEP_INP(sc->sc_yp_inp) | sc->sc_xn_bit;
628 	else if (sc->sc_tsc_wires == 5)
629 		stepconfig |= ADC_STEP_INP(4) |
630 			sc->sc_xn_bit | sc->sc_yn_bit | sc->sc_yp_bit;
631 	else if (sc->sc_tsc_wires == 8)
632 		stepconfig |= ADC_STEP_INP(sc->sc_yp_inp) | sc->sc_xn_bit;
633 
634 	start_step = ADC_STEPS - sc->sc_coord_readouts + 1;
635 	end_step = start_step + sc->sc_coord_readouts - 1;
636 	for (i = start_step; i <= end_step; i++) {
637 		ADC_WRITE4(sc, ADC_STEPCFG(i), stepconfig);
638 		ADC_WRITE4(sc, ADC_STEPDLY(i), STEPDLY_OPEN);
639 	}
640 
641 	/* Y coordinates */
642 	stepconfig = ADC_STEP_FIFO1 | (4 << ADC_STEP_AVG_SHIFT) |
643 	    ADC_STEP_MODE_HW_ONESHOT | sc->sc_yn_bit |
644 	    ADC_STEP_INM(8);
645 	if (sc->sc_tsc_wires == 4)
646 		stepconfig |= ADC_STEP_INP(sc->sc_xp_inp) | sc->sc_yp_bit;
647 	else if (sc->sc_tsc_wires == 5)
648 		stepconfig |= ADC_STEP_INP(4) |
649 			sc->sc_xp_bit | sc->sc_xn_bit | sc->sc_yp_bit;
650 	else if (sc->sc_tsc_wires == 8)
651 		stepconfig |= ADC_STEP_INP(sc->sc_xp_inp) | sc->sc_yp_bit;
652 
653 	start_step = ADC_STEPS - (sc->sc_coord_readouts*2 + 2) + 1;
654 	end_step = start_step + sc->sc_coord_readouts - 1;
655 	for (i = start_step; i <= end_step; i++) {
656 		ADC_WRITE4(sc, ADC_STEPCFG(i), stepconfig);
657 		ADC_WRITE4(sc, ADC_STEPDLY(i), STEPDLY_OPEN);
658 	}
659 
660 	/* Charge config */
661 	val = ADC_READ4(sc, ADC_IDLECONFIG);
662 	ADC_WRITE4(sc, ADC_TC_CHARGE_STEPCONFIG, val);
663 	ADC_WRITE4(sc, ADC_TC_CHARGE_DELAY, sc->sc_charge_delay);
664 
665 	/* 2 steps for Z */
666 	start_step = ADC_STEPS - (sc->sc_coord_readouts + 2) + 1;
667 	stepconfig = ADC_STEP_FIFO1 | (4 << ADC_STEP_AVG_SHIFT) |
668 	    ADC_STEP_MODE_HW_ONESHOT | sc->sc_yp_bit |
669 	    sc->sc_xn_bit | ADC_STEP_INP(sc->sc_xp_inp) |
670 	    ADC_STEP_INM(8);
671 	ADC_WRITE4(sc, ADC_STEPCFG(start_step), stepconfig);
672 	ADC_WRITE4(sc, ADC_STEPDLY(start_step), STEPDLY_OPEN);
673 	start_step++;
674 	stepconfig |= ADC_STEP_INP(sc->sc_yn_inp);
675 	ADC_WRITE4(sc, ADC_STEPCFG(start_step), stepconfig);
676 	ADC_WRITE4(sc, ADC_STEPDLY(start_step), STEPDLY_OPEN);
677 
678 	ADC_WRITE4(sc, ADC_FIFO1THRESHOLD, (sc->sc_coord_readouts*2 + 2) - 1);
679 
680 	sc->sc_tsc_enabled = 1;
681 	start_step = ADC_STEPS - (sc->sc_coord_readouts*2 + 2) + 1;
682 	end_step = ADC_STEPS;
683 	for (i = start_step; i <= end_step; i++) {
684 		sc->sc_tsc_enabled |= (1 << i);
685 	}
686 
687 	TI_ADC_UNLOCK(sc);
688 }
689 
690 static void
ti_adc_idlestep_init(struct ti_adc_softc * sc)691 ti_adc_idlestep_init(struct ti_adc_softc *sc)
692 {
693 	uint32_t val;
694 
695 	val = ADC_STEP_YNN_SW | ADC_STEP_INM(8) | ADC_STEP_INP(8) | ADC_STEP_YPN_SW;
696 
697 	ADC_WRITE4(sc, ADC_IDLECONFIG, val);
698 }
699 
700 static int
ti_adc_config_wires(struct ti_adc_softc * sc,int * wire_configs,int nwire_configs)701 ti_adc_config_wires(struct ti_adc_softc *sc, int *wire_configs, int nwire_configs)
702 {
703 	int i;
704 	int wire, ai;
705 
706 	for (i = 0; i < nwire_configs; i++) {
707 		wire = wire_configs[i] & 0xf;
708 		ai = (wire_configs[i] >> 4) & 0xf;
709 		switch (wire) {
710 		case ORDER_XP:
711 			sc->sc_xp_bit = ADC_STEP_XPP_SW;
712 			sc->sc_xp_inp = ai;
713 			break;
714 		case ORDER_XN:
715 			sc->sc_xn_bit = ADC_STEP_XNN_SW;
716 			sc->sc_xn_inp = ai;
717 			break;
718 		case ORDER_YP:
719 			sc->sc_yp_bit = ADC_STEP_YPP_SW;
720 			sc->sc_yp_inp = ai;
721 			break;
722 		case ORDER_YN:
723 			sc->sc_yn_bit = ADC_STEP_YNN_SW;
724 			sc->sc_yn_inp = ai;
725 			break;
726 		default:
727 			device_printf(sc->sc_dev, "Invalid wire config\n");
728 			return (-1);
729 		}
730 	}
731 	return (0);
732 }
733 
734 static int
ti_adc_probe(device_t dev)735 ti_adc_probe(device_t dev)
736 {
737 
738 	if (!ofw_bus_is_compatible(dev, "ti,am3359-tscadc"))
739 		return (ENXIO);
740 	device_set_desc(dev, "TI ADC controller");
741 
742 	return (BUS_PROBE_DEFAULT);
743 }
744 
745 static int
ti_adc_attach(device_t dev)746 ti_adc_attach(device_t dev)
747 {
748 	int err, rid, i;
749 	struct ti_adc_softc *sc;
750 	uint32_t rev, reg;
751 	phandle_t node, child;
752 	pcell_t cell;
753 	int *channels;
754 	int nwire_configs;
755 	int *wire_configs;
756 
757 	sc = device_get_softc(dev);
758 	sc->sc_dev = dev;
759 
760 	node = ofw_bus_get_node(dev);
761 
762 	sc->sc_tsc_wires = 0;
763 	sc->sc_coord_readouts = 1;
764 	sc->sc_x_plate_resistance = 0;
765 	sc->sc_charge_delay = DEFAULT_CHARGE_DELAY;
766 	/* Read "tsc" node properties */
767 	child = ofw_bus_find_child(node, "tsc");
768 	if (child != 0 && OF_hasprop(child, "ti,wires")) {
769 		if ((OF_getencprop(child, "ti,wires", &cell, sizeof(cell))) > 0)
770 			sc->sc_tsc_wires = cell;
771 		if ((OF_getencprop(child, "ti,coordinate-readouts", &cell,
772 		    sizeof(cell))) > 0)
773 			sc->sc_coord_readouts = cell;
774 		if ((OF_getencprop(child, "ti,x-plate-resistance", &cell,
775 		    sizeof(cell))) > 0)
776 			sc->sc_x_plate_resistance = cell;
777 		if ((OF_getencprop(child, "ti,charge-delay", &cell,
778 		    sizeof(cell))) > 0)
779 			sc->sc_charge_delay = cell;
780 		nwire_configs = OF_getencprop_alloc_multi(child,
781 		    "ti,wire-config", sizeof(*wire_configs),
782 		    (void **)&wire_configs);
783 		if (nwire_configs != sc->sc_tsc_wires) {
784 			device_printf(sc->sc_dev,
785 			    "invalid number of ti,wire-config: %d (should be %d)\n",
786 			    nwire_configs, sc->sc_tsc_wires);
787 			OF_prop_free(wire_configs);
788 			return (EINVAL);
789 		}
790 		err = ti_adc_config_wires(sc, wire_configs, nwire_configs);
791 		OF_prop_free(wire_configs);
792 		if (err)
793 			return (EINVAL);
794 	}
795 
796 	/* Read "adc" node properties */
797 	child = ofw_bus_find_child(node, "adc");
798 	if (child != 0) {
799 		sc->sc_adc_nchannels = OF_getencprop_alloc_multi(child,
800 		    "ti,adc-channels", sizeof(*channels), (void **)&channels);
801 		if (sc->sc_adc_nchannels > 0) {
802 			for (i = 0; i < sc->sc_adc_nchannels; i++)
803 				sc->sc_adc_channels[i] = channels[i];
804 			OF_prop_free(channels);
805 		}
806 	}
807 
808 	/* Sanity check FDT data */
809 	if (sc->sc_tsc_wires + sc->sc_adc_nchannels > TI_ADC_NPINS) {
810 		device_printf(dev, "total number of channels (%d) is larger than %d\n",
811 		    sc->sc_tsc_wires + sc->sc_adc_nchannels, TI_ADC_NPINS);
812 		return (ENXIO);
813 	}
814 
815 	rid = 0;
816 	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
817 	    RF_ACTIVE);
818 	if (!sc->sc_mem_res) {
819 		device_printf(dev, "cannot allocate memory window\n");
820 		return (ENXIO);
821 	}
822 
823 	/* Activate the ADC_TSC module. */
824 	err = ti_sysc_clock_enable(device_get_parent(dev));
825 	if (err)
826 		return (err);
827 
828 	rid = 0;
829 	sc->sc_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
830 	    RF_ACTIVE);
831 	if (!sc->sc_irq_res) {
832 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
833 		device_printf(dev, "cannot allocate interrupt\n");
834 		return (ENXIO);
835 	}
836 
837 	if (bus_setup_intr(dev, sc->sc_irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
838 	    NULL, ti_adc_intr, sc, &sc->sc_intrhand) != 0) {
839 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res);
840 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
841 		device_printf(dev, "Unable to setup the irq handler.\n");
842 		return (ENXIO);
843 	}
844 
845 	/* Check the ADC revision. */
846 	rev = ADC_READ4(sc, ti_sysc_get_rev_address_offset_host(device_get_parent(dev)));
847 	device_printf(dev,
848 	    "scheme: %#x func: %#x rtl: %d rev: %d.%d custom rev: %d\n",
849 	    (rev & ADC_REV_SCHEME_MSK) >> ADC_REV_SCHEME_SHIFT,
850 	    (rev & ADC_REV_FUNC_MSK) >> ADC_REV_FUNC_SHIFT,
851 	    (rev & ADC_REV_RTL_MSK) >> ADC_REV_RTL_SHIFT,
852 	    (rev & ADC_REV_MAJOR_MSK) >> ADC_REV_MAJOR_SHIFT,
853 	    rev & ADC_REV_MINOR_MSK,
854 	    (rev & ADC_REV_CUSTOM_MSK) >> ADC_REV_CUSTOM_SHIFT);
855 
856 	reg = ADC_READ4(sc, ADC_CTRL);
857 	ADC_WRITE4(sc, ADC_CTRL, reg | ADC_CTRL_STEP_WP | ADC_CTRL_STEP_ID);
858 
859 	/*
860 	 * Set the ADC prescaler to 2400 if touchscreen is not enabled
861 	 * and to 24 if it is.  This sets the ADC clock to ~10Khz and
862 	 * ~1Mhz respectively (CLK_M_OSC / prescaler).
863 	 */
864 	if (sc->sc_tsc_wires)
865 		ADC_WRITE4(sc, ADC_CLKDIV, 24 - 1);
866 	else
867 		ADC_WRITE4(sc, ADC_CLKDIV, 2400 - 1);
868 
869 	TI_ADC_LOCK_INIT(sc);
870 
871 	ti_adc_idlestep_init(sc);
872 	ti_adc_inputs_init(sc);
873 	ti_adc_sysctl_init(sc);
874 	ti_adc_tsc_init(sc);
875 
876 	TI_ADC_LOCK(sc);
877 	ti_adc_setup(sc);
878 	TI_ADC_UNLOCK(sc);
879 
880 #ifdef EVDEV_SUPPORT
881 	if (sc->sc_tsc_wires > 0) {
882 		sc->sc_evdev = evdev_alloc();
883 		evdev_set_name(sc->sc_evdev, device_get_desc(dev));
884 		evdev_set_phys(sc->sc_evdev, device_get_nameunit(dev));
885 		evdev_set_id(sc->sc_evdev, BUS_VIRTUAL, 0, 0, 0);
886 		evdev_support_prop(sc->sc_evdev, INPUT_PROP_DIRECT);
887 		evdev_support_event(sc->sc_evdev, EV_SYN);
888 		evdev_support_event(sc->sc_evdev, EV_ABS);
889 		evdev_support_event(sc->sc_evdev, EV_KEY);
890 
891 		evdev_support_abs(sc->sc_evdev, ABS_X, 0,
892 		    ADC_MAX_VALUE, 0, 0, 0);
893 		evdev_support_abs(sc->sc_evdev, ABS_Y, 0,
894 		    ADC_MAX_VALUE, 0, 0, 0);
895 
896 		evdev_support_key(sc->sc_evdev, BTN_TOUCH);
897 
898 		err = evdev_register(sc->sc_evdev);
899 		if (err) {
900 			device_printf(dev,
901 			    "failed to register evdev: error=%d\n", err);
902 			ti_adc_detach(dev);
903 			return (err);
904 		}
905 
906 		sc->sc_pen_down = 0;
907 		sc->sc_x = -1;
908 		sc->sc_y = -1;
909 	}
910 #endif /* EVDEV */
911 
912 	return (0);
913 }
914 
915 static int
ti_adc_detach(device_t dev)916 ti_adc_detach(device_t dev)
917 {
918 	struct ti_adc_softc *sc;
919 
920 	sc = device_get_softc(dev);
921 
922 	/* Turn off the ADC. */
923 	TI_ADC_LOCK(sc);
924 	ti_adc_reset(sc);
925 	ti_adc_setup(sc);
926 
927 #ifdef EVDEV_SUPPORT
928 	evdev_free(sc->sc_evdev);
929 #endif
930 
931 	TI_ADC_UNLOCK(sc);
932 
933 	TI_ADC_LOCK_DESTROY(sc);
934 
935 	if (sc->sc_intrhand)
936 		bus_teardown_intr(dev, sc->sc_irq_res, sc->sc_intrhand);
937 	if (sc->sc_irq_res)
938 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res);
939 	if (sc->sc_mem_res)
940 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
941 
942 	return (bus_generic_detach(dev));
943 }
944 
945 static device_method_t ti_adc_methods[] = {
946 	DEVMETHOD(device_probe,		ti_adc_probe),
947 	DEVMETHOD(device_attach,	ti_adc_attach),
948 	DEVMETHOD(device_detach,	ti_adc_detach),
949 
950 	DEVMETHOD_END
951 };
952 
953 static driver_t ti_adc_driver = {
954 	"ti_adc",
955 	ti_adc_methods,
956 	sizeof(struct ti_adc_softc),
957 };
958 
959 static devclass_t ti_adc_devclass;
960 
961 DRIVER_MODULE(ti_adc, simplebus, ti_adc_driver, ti_adc_devclass, 0, 0);
962 MODULE_VERSION(ti_adc, 1);
963 MODULE_DEPEND(ti_adc, simplebus, 1, 1, 1);
964 MODULE_DEPEND(ti_adc, ti_sysc, 1, 1, 1);
965 #ifdef EVDEV_SUPPORT
966 MODULE_DEPEND(ti_adc, evdev, 1, 1, 1);
967 #endif
968