xref: /freebsd/sys/arm/ti/ti_adc.c (revision eaa797943eeac5614edfdc8f6309f332343c3dd2)
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 __FBSDID("$FreeBSD$");
29 
30 #include "opt_evdev.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 
36 #include <sys/conf.h>
37 #include <sys/kernel.h>
38 #include <sys/limits.h>
39 #include <sys/lock.h>
40 #include <sys/module.h>
41 #include <sys/mutex.h>
42 #include <sys/condvar.h>
43 #include <sys/resource.h>
44 #include <sys/rman.h>
45 #include <sys/sysctl.h>
46 #include <sys/selinfo.h>
47 #include <sys/poll.h>
48 #include <sys/uio.h>
49 
50 #include <machine/bus.h>
51 
52 #include <dev/fdt/fdt_common.h>
53 #include <dev/ofw/openfirm.h>
54 #include <dev/ofw/ofw_bus.h>
55 #include <dev/ofw/ofw_bus_subr.h>
56 
57 #ifdef EVDEV
58 #include <dev/evdev/input.h>
59 #include <dev/evdev/evdev.h>
60 #endif
61 
62 #include <arm/ti/ti_prcm.h>
63 #include <arm/ti/ti_adcreg.h>
64 #include <arm/ti/ti_adcvar.h>
65 
66 #undef	DEBUG_TSC
67 
68 #define	DEFAULT_CHARGE_DELAY	0x400
69 #define	STEPDLY_OPEN		0x98
70 
71 #define	ORDER_XP	0
72 #define	ORDER_XN	1
73 #define	ORDER_YP	2
74 #define	ORDER_YN	3
75 
76 /* Define our 8 steps, one for each input channel. */
77 static struct ti_adc_input ti_adc_inputs[TI_ADC_NPINS] = {
78 	{ .stepconfig = ADC_STEPCFG(1), .stepdelay = ADC_STEPDLY(1) },
79 	{ .stepconfig = ADC_STEPCFG(2), .stepdelay = ADC_STEPDLY(2) },
80 	{ .stepconfig = ADC_STEPCFG(3), .stepdelay = ADC_STEPDLY(3) },
81 	{ .stepconfig = ADC_STEPCFG(4), .stepdelay = ADC_STEPDLY(4) },
82 	{ .stepconfig = ADC_STEPCFG(5), .stepdelay = ADC_STEPDLY(5) },
83 	{ .stepconfig = ADC_STEPCFG(6), .stepdelay = ADC_STEPDLY(6) },
84 	{ .stepconfig = ADC_STEPCFG(7), .stepdelay = ADC_STEPDLY(7) },
85 	{ .stepconfig = ADC_STEPCFG(8), .stepdelay = ADC_STEPDLY(8) },
86 };
87 
88 static int ti_adc_samples[5] = { 0, 2, 4, 8, 16 };
89 
90 static int ti_adc_detach(device_t dev);
91 
92 #ifdef EVDEV
93 static void
94 ti_adc_ev_report(struct ti_adc_softc *sc)
95 {
96 
97 	evdev_push_event(sc->sc_evdev, EV_ABS, ABS_X, sc->sc_x);
98 	evdev_push_event(sc->sc_evdev, EV_ABS, ABS_Y, sc->sc_y);
99 	evdev_push_event(sc->sc_evdev, EV_KEY, BTN_TOUCH, sc->sc_pen_down);
100 	evdev_sync(sc->sc_evdev);
101 }
102 #endif /* EVDEV */
103 
104 static void
105 ti_adc_enable(struct ti_adc_softc *sc)
106 {
107 	uint32_t reg;
108 
109 	TI_ADC_LOCK_ASSERT(sc);
110 
111 	if (sc->sc_last_state == 1)
112 		return;
113 
114 	/* Enable the FIFO0 threshold and the end of sequence interrupt. */
115 	ADC_WRITE4(sc, ADC_IRQENABLE_SET,
116 	    ADC_IRQ_FIFO0_THRES | ADC_IRQ_FIFO1_THRES | ADC_IRQ_END_OF_SEQ);
117 
118 	reg = ADC_CTRL_STEP_WP | ADC_CTRL_STEP_ID;
119 	if (sc->sc_tsc_wires > 0) {
120 		reg |= ADC_CTRL_TSC_ENABLE;
121 		switch (sc->sc_tsc_wires) {
122 		case 4:
123 			reg |= ADC_CTRL_TSC_4WIRE;
124 			break;
125 		case 5:
126 			reg |= ADC_CTRL_TSC_5WIRE;
127 			break;
128 		case 8:
129 			reg |= ADC_CTRL_TSC_8WIRE;
130 			break;
131 		default:
132 			break;
133 		}
134 	}
135 	reg |= ADC_CTRL_ENABLE;
136 	/* Enable the ADC.  Run thru enabled steps, start the conversions. */
137 	ADC_WRITE4(sc, ADC_CTRL, reg);
138 
139 	sc->sc_last_state = 1;
140 }
141 
142 static void
143 ti_adc_disable(struct ti_adc_softc *sc)
144 {
145 	int count;
146 	uint32_t data;
147 
148 	TI_ADC_LOCK_ASSERT(sc);
149 
150 	if (sc->sc_last_state == 0)
151 		return;
152 
153 	/* Disable all the enabled steps. */
154 	ADC_WRITE4(sc, ADC_STEPENABLE, 0);
155 
156 	/* Disable the ADC. */
157 	ADC_WRITE4(sc, ADC_CTRL, ADC_READ4(sc, ADC_CTRL) & ~ADC_CTRL_ENABLE);
158 
159 	/* Disable the FIFO0 threshold and the end of sequence interrupt. */
160 	ADC_WRITE4(sc, ADC_IRQENABLE_CLR,
161 	    ADC_IRQ_FIFO0_THRES | ADC_IRQ_FIFO1_THRES | ADC_IRQ_END_OF_SEQ);
162 
163 	/* ACK any pending interrupt. */
164 	ADC_WRITE4(sc, ADC_IRQSTATUS, ADC_READ4(sc, ADC_IRQSTATUS));
165 
166 	/* Drain the FIFO data. */
167 	count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
168 	while (count > 0) {
169 		data = ADC_READ4(sc, ADC_FIFO0DATA);
170 		count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
171 	}
172 
173 	count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
174 	while (count > 0) {
175 		data = ADC_READ4(sc, ADC_FIFO1DATA);
176 		count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
177 	}
178 
179 	sc->sc_last_state = 0;
180 }
181 
182 static int
183 ti_adc_setup(struct ti_adc_softc *sc)
184 {
185 	int ain, i;
186 	uint32_t enabled;
187 
188 	TI_ADC_LOCK_ASSERT(sc);
189 
190 	/* Check for enabled inputs. */
191 	enabled = sc->sc_tsc_enabled;
192 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
193 		ain = sc->sc_adc_channels[i];
194 		if (ti_adc_inputs[ain].enable)
195 			enabled |= (1U << (ain + 1));
196 	}
197 
198 	/* Set the ADC global status. */
199 	if (enabled != 0) {
200 		ti_adc_enable(sc);
201 		/* Update the enabled steps. */
202 		if (enabled != ADC_READ4(sc, ADC_STEPENABLE))
203 			ADC_WRITE4(sc, ADC_STEPENABLE, enabled);
204 	} else
205 		ti_adc_disable(sc);
206 
207 	return (0);
208 }
209 
210 static void
211 ti_adc_input_setup(struct ti_adc_softc *sc, int32_t ain)
212 {
213 	struct ti_adc_input *input;
214 	uint32_t reg, val;
215 
216 	TI_ADC_LOCK_ASSERT(sc);
217 
218 	input = &ti_adc_inputs[ain];
219 	reg = input->stepconfig;
220 	val = ADC_READ4(sc, reg);
221 
222 	/* Set single ended operation. */
223 	val &= ~ADC_STEP_DIFF_CNTRL;
224 
225 	/* Set the negative voltage reference. */
226 	val &= ~ADC_STEP_RFM_MSK;
227 
228 	/* Set the positive voltage reference. */
229 	val &= ~ADC_STEP_RFP_MSK;
230 
231 	/* Set the samples average. */
232 	val &= ~ADC_STEP_AVG_MSK;
233 	val |= input->samples << ADC_STEP_AVG_SHIFT;
234 
235 	/* Select the desired input. */
236 	val &= ~ADC_STEP_INP_MSK;
237 	val |= ain << ADC_STEP_INP_SHIFT;
238 
239 	/* Set the ADC to one-shot mode. */
240 	val &= ~ADC_STEP_MODE_MSK;
241 
242 	ADC_WRITE4(sc, reg, val);
243 }
244 
245 static void
246 ti_adc_reset(struct ti_adc_softc *sc)
247 {
248 	int ain, i;
249 
250 	TI_ADC_LOCK_ASSERT(sc);
251 
252 	/* Disable all the inputs. */
253 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
254 		ain = sc->sc_adc_channels[i];
255 		ti_adc_inputs[ain].enable = 0;
256 	}
257 }
258 
259 static int
260 ti_adc_clockdiv_proc(SYSCTL_HANDLER_ARGS)
261 {
262 	int error, reg;
263 	struct ti_adc_softc *sc;
264 
265 	sc = (struct ti_adc_softc *)arg1;
266 
267 	TI_ADC_LOCK(sc);
268 	reg = (int)ADC_READ4(sc, ADC_CLKDIV) + 1;
269 	TI_ADC_UNLOCK(sc);
270 
271 	error = sysctl_handle_int(oidp, &reg, sizeof(reg), req);
272 	if (error != 0 || req->newptr == NULL)
273 		return (error);
274 
275 	/*
276 	 * The actual written value is the prescaler setting - 1.
277 	 * Enforce a minimum value of 10 (i.e. 9) which limits the maximum
278 	 * ADC clock to ~2.4Mhz (CLK_M_OSC / 10).
279 	 */
280 	reg--;
281 	if (reg < 9)
282 		reg = 9;
283 	if (reg > USHRT_MAX)
284 		reg = USHRT_MAX;
285 
286 	TI_ADC_LOCK(sc);
287 	/* Disable the ADC. */
288 	ti_adc_disable(sc);
289 	/* Update the ADC prescaler setting. */
290 	ADC_WRITE4(sc, ADC_CLKDIV, reg);
291 	/* Enable the ADC again. */
292 	ti_adc_setup(sc);
293 	TI_ADC_UNLOCK(sc);
294 
295 	return (0);
296 }
297 
298 static int
299 ti_adc_enable_proc(SYSCTL_HANDLER_ARGS)
300 {
301 	int error;
302 	int32_t enable;
303 	struct ti_adc_softc *sc;
304 	struct ti_adc_input *input;
305 
306 	input = (struct ti_adc_input *)arg1;
307 	sc = input->sc;
308 
309 	enable = input->enable;
310 	error = sysctl_handle_int(oidp, &enable, sizeof(enable),
311 	    req);
312 	if (error != 0 || req->newptr == NULL)
313 		return (error);
314 
315 	if (enable)
316 		enable = 1;
317 
318 	TI_ADC_LOCK(sc);
319 	/* Setup the ADC as needed. */
320 	if (input->enable != enable) {
321 		input->enable = enable;
322 		ti_adc_setup(sc);
323 		if (input->enable == 0)
324 			input->value = 0;
325 	}
326 	TI_ADC_UNLOCK(sc);
327 
328 	return (0);
329 }
330 
331 static int
332 ti_adc_open_delay_proc(SYSCTL_HANDLER_ARGS)
333 {
334 	int error, reg;
335 	struct ti_adc_softc *sc;
336 	struct ti_adc_input *input;
337 
338 	input = (struct ti_adc_input *)arg1;
339 	sc = input->sc;
340 
341 	TI_ADC_LOCK(sc);
342 	reg = (int)ADC_READ4(sc, input->stepdelay) & ADC_STEP_OPEN_DELAY;
343 	TI_ADC_UNLOCK(sc);
344 
345 	error = sysctl_handle_int(oidp, &reg, sizeof(reg), req);
346 	if (error != 0 || req->newptr == NULL)
347 		return (error);
348 
349 	if (reg < 0)
350 		reg = 0;
351 
352 	TI_ADC_LOCK(sc);
353 	ADC_WRITE4(sc, input->stepdelay, reg & ADC_STEP_OPEN_DELAY);
354 	TI_ADC_UNLOCK(sc);
355 
356 	return (0);
357 }
358 
359 static int
360 ti_adc_samples_avg_proc(SYSCTL_HANDLER_ARGS)
361 {
362 	int error, samples, i;
363 	struct ti_adc_softc *sc;
364 	struct ti_adc_input *input;
365 
366 	input = (struct ti_adc_input *)arg1;
367 	sc = input->sc;
368 
369 	if (input->samples > nitems(ti_adc_samples))
370 		input->samples = nitems(ti_adc_samples);
371 	samples = ti_adc_samples[input->samples];
372 
373 	error = sysctl_handle_int(oidp, &samples, 0, req);
374 	if (error != 0 || req->newptr == NULL)
375 		return (error);
376 
377 	TI_ADC_LOCK(sc);
378 	if (samples != ti_adc_samples[input->samples]) {
379 		input->samples = 0;
380 		for (i = 0; i < nitems(ti_adc_samples); i++)
381 			if (samples >= ti_adc_samples[i])
382 				input->samples = i;
383 		ti_adc_input_setup(sc, input->input);
384 	}
385 	TI_ADC_UNLOCK(sc);
386 
387 	return (error);
388 }
389 
390 static void
391 ti_adc_read_data(struct ti_adc_softc *sc)
392 {
393 	int count, ain;
394 	struct ti_adc_input *input;
395 	uint32_t data;
396 
397 	TI_ADC_LOCK_ASSERT(sc);
398 
399 	/* Read the available data. */
400 	count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
401 	while (count > 0) {
402 		data = ADC_READ4(sc, ADC_FIFO0DATA);
403 		ain = (data & ADC_FIFO_STEP_ID_MSK) >> ADC_FIFO_STEP_ID_SHIFT;
404 		input = &ti_adc_inputs[ain];
405 		if (input->enable == 0)
406 			input->value = 0;
407 		else
408 			input->value = (int32_t)(data & ADC_FIFO_DATA_MSK);
409 		count = ADC_READ4(sc, ADC_FIFO0COUNT) & ADC_FIFO_COUNT_MSK;
410 	}
411 }
412 
413 static int
414 cmp_values(const void *a, const void *b)
415 {
416 	const uint32_t *v1, *v2;
417 	v1 = a;
418 	v2 = b;
419 	if (*v1 < *v2)
420 		return -1;
421 	if (*v1 > *v2)
422 		return 1;
423 
424 	return (0);
425 }
426 
427 static void
428 ti_adc_tsc_read_data(struct ti_adc_softc *sc)
429 {
430 	int count;
431 	uint32_t data[16];
432 	uint32_t x, y;
433 	int i, start, end;
434 
435 	TI_ADC_LOCK_ASSERT(sc);
436 
437 	/* Read the available data. */
438 	count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
439 	if (count == 0)
440 		return;
441 
442 	i = 0;
443 	while (count > 0) {
444 		data[i++] = ADC_READ4(sc, ADC_FIFO1DATA) & ADC_FIFO_DATA_MSK;
445 		count = ADC_READ4(sc, ADC_FIFO1COUNT) & ADC_FIFO_COUNT_MSK;
446 	}
447 
448 	if (sc->sc_coord_readouts > 3) {
449 		start = 1;
450 		end = sc->sc_coord_readouts - 1;
451 		qsort(data, sc->sc_coord_readouts,
452 			sizeof(data[0]), &cmp_values);
453 		qsort(&data[sc->sc_coord_readouts + 2],
454 			sc->sc_coord_readouts,
455 			sizeof(data[0]), &cmp_values);
456 	}
457 	else {
458 		start = 0;
459 		end = sc->sc_coord_readouts;
460 	}
461 
462 	x = y = 0;
463 	for (i = start; i < end; i++)
464 		y += data[i];
465 	y /= (end - start);
466 
467 	for (i = sc->sc_coord_readouts + 2 + start; i < sc->sc_coord_readouts + 2 + end; i++)
468 		x += data[i];
469 	x /= (end - start);
470 
471 #ifdef DEBUG_TSC
472 	device_printf(sc->sc_dev, "touchscreen x: %d, y: %d\n", x, y);
473 #endif
474 
475 #ifdef EVDEV
476 	if ((sc->sc_x != x) || (sc->sc_y != y)) {
477 		sc->sc_x = x;
478 		sc->sc_y = y;
479 		ti_adc_ev_report(sc);
480 	}
481 #endif
482 }
483 
484 static void
485 ti_adc_intr_locked(struct ti_adc_softc *sc, uint32_t status)
486 {
487 	/* Read the available data. */
488 	if (status & ADC_IRQ_FIFO0_THRES)
489 		ti_adc_read_data(sc);
490 }
491 
492 static void
493 ti_adc_tsc_intr_locked(struct ti_adc_softc *sc, uint32_t status)
494 {
495 	/* Read the available data. */
496 	if (status & ADC_IRQ_FIFO1_THRES)
497 		ti_adc_tsc_read_data(sc);
498 
499 }
500 
501 static void
502 ti_adc_intr(void *arg)
503 {
504 	struct ti_adc_softc *sc;
505 	uint32_t status, rawstatus;
506 
507 	sc = (struct ti_adc_softc *)arg;
508 
509 	TI_ADC_LOCK(sc);
510 
511 	rawstatus = ADC_READ4(sc, ADC_IRQSTATUS_RAW);
512 	status = ADC_READ4(sc, ADC_IRQSTATUS);
513 
514 	if (rawstatus & ADC_IRQ_HW_PEN_ASYNC) {
515 		sc->sc_pen_down = 1;
516 		status |= ADC_IRQ_HW_PEN_ASYNC;
517 		ADC_WRITE4(sc, ADC_IRQENABLE_CLR,
518 			ADC_IRQ_HW_PEN_ASYNC);
519 #ifdef EVDEV
520 		ti_adc_ev_report(sc);
521 #endif
522 	}
523 
524 	if (rawstatus & ADC_IRQ_PEN_UP) {
525 		sc->sc_pen_down = 0;
526 		status |= ADC_IRQ_PEN_UP;
527 #ifdef EVDEV
528 		ti_adc_ev_report(sc);
529 #endif
530 	}
531 
532 	if (status & ADC_IRQ_FIFO0_THRES)
533 		ti_adc_intr_locked(sc, status);
534 
535 	if (status & ADC_IRQ_FIFO1_THRES)
536 		ti_adc_tsc_intr_locked(sc, status);
537 
538 	if (status) {
539 		/* ACK the interrupt. */
540 		ADC_WRITE4(sc, ADC_IRQSTATUS, status);
541 	}
542 
543 	/* Start the next conversion ? */
544 	if (status & ADC_IRQ_END_OF_SEQ)
545 		ti_adc_setup(sc);
546 
547 	TI_ADC_UNLOCK(sc);
548 }
549 
550 static void
551 ti_adc_sysctl_init(struct ti_adc_softc *sc)
552 {
553 	char pinbuf[3];
554 	struct sysctl_ctx_list *ctx;
555 	struct sysctl_oid *tree_node, *inp_node, *inpN_node;
556 	struct sysctl_oid_list *tree, *inp_tree, *inpN_tree;
557 	int ain, i;
558 
559 	/*
560 	 * Add per-pin sysctl tree/handlers.
561 	 */
562 	ctx = device_get_sysctl_ctx(sc->sc_dev);
563 	tree_node = device_get_sysctl_tree(sc->sc_dev);
564 	tree = SYSCTL_CHILDREN(tree_node);
565 	SYSCTL_ADD_PROC(ctx, tree, OID_AUTO, "clockdiv",
566 	    CTLFLAG_RW | CTLTYPE_UINT,  sc, 0,
567 	    ti_adc_clockdiv_proc, "IU", "ADC clock prescaler");
568 	inp_node = SYSCTL_ADD_NODE(ctx, tree, OID_AUTO, "ain",
569 	    CTLFLAG_RD, NULL, "ADC inputs");
570 	inp_tree = SYSCTL_CHILDREN(inp_node);
571 
572 	for (i = 0; i < sc->sc_adc_nchannels; i++) {
573 		ain = sc->sc_adc_channels[i];
574 
575 		snprintf(pinbuf, sizeof(pinbuf), "%d", ain);
576 		inpN_node = SYSCTL_ADD_NODE(ctx, inp_tree, OID_AUTO, pinbuf,
577 		    CTLFLAG_RD, NULL, "ADC input");
578 		inpN_tree = SYSCTL_CHILDREN(inpN_node);
579 
580 		SYSCTL_ADD_PROC(ctx, inpN_tree, OID_AUTO, "enable",
581 		    CTLFLAG_RW | CTLTYPE_UINT, &ti_adc_inputs[ain], 0,
582 		    ti_adc_enable_proc, "IU", "Enable ADC input");
583 		SYSCTL_ADD_PROC(ctx, inpN_tree, OID_AUTO, "open_delay",
584 		    CTLFLAG_RW | CTLTYPE_UINT,  &ti_adc_inputs[ain], 0,
585 		    ti_adc_open_delay_proc, "IU", "ADC open delay");
586 		SYSCTL_ADD_PROC(ctx, inpN_tree, OID_AUTO, "samples_avg",
587 		    CTLFLAG_RW | CTLTYPE_UINT,  &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
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
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 
688 	TI_ADC_UNLOCK(sc);
689 }
690 
691 static void
692 ti_adc_idlestep_init(struct ti_adc_softc *sc)
693 {
694 	uint32_t val;
695 
696 	val = ADC_STEP_YNN_SW | ADC_STEP_INM(8) | ADC_STEP_INP(8) | ADC_STEP_YPN_SW;
697 
698 	ADC_WRITE4(sc, ADC_IDLECONFIG, val);
699 }
700 
701 static int
702 ti_adc_config_wires(struct ti_adc_softc *sc, int *wire_configs, int nwire_configs)
703 {
704 	int i;
705 	int wire, ai;
706 
707 	for (i = 0; i < nwire_configs; i++) {
708 		wire = wire_configs[i] & 0xf;
709 		ai = (wire_configs[i] >> 4) & 0xf;
710 		switch (wire) {
711 		case ORDER_XP:
712 			sc->sc_xp_bit = ADC_STEP_XPP_SW;
713 			sc->sc_xp_inp = ai;
714 			break;
715 		case ORDER_XN:
716 			sc->sc_xn_bit = ADC_STEP_XNN_SW;
717 			sc->sc_xn_inp = ai;
718 			break;
719 		case ORDER_YP:
720 			sc->sc_yp_bit = ADC_STEP_YPP_SW;
721 			sc->sc_yp_inp = ai;
722 			break;
723 		case ORDER_YN:
724 			sc->sc_yn_bit = ADC_STEP_YNN_SW;
725 			sc->sc_yn_inp = ai;
726 			break;
727 		default:
728 			device_printf(sc->sc_dev, "Invalid wire config\n");
729 			return (-1);
730 		}
731 	}
732 	return (0);
733 }
734 
735 static int
736 ti_adc_probe(device_t dev)
737 {
738 
739 	if (!ofw_bus_is_compatible(dev, "ti,am3359-tscadc"))
740 		return (ENXIO);
741 	device_set_desc(dev, "TI ADC controller");
742 
743 	return (BUS_PROBE_DEFAULT);
744 }
745 
746 static int
747 ti_adc_attach(device_t dev)
748 {
749 	int err, rid, i;
750 	struct ti_adc_softc *sc;
751 	uint32_t rev, reg;
752 	phandle_t node, child;
753 	pcell_t cell;
754 	int *channels;
755 	int nwire_configs;
756 	int *wire_configs;
757 
758 	sc = device_get_softc(dev);
759 	sc->sc_dev = dev;
760 
761 	node = ofw_bus_get_node(dev);
762 
763 	sc->sc_tsc_wires = 0;
764 	sc->sc_coord_readouts = 1;
765 	sc->sc_x_plate_resistance = 0;
766 	sc->sc_charge_delay = DEFAULT_CHARGE_DELAY;
767 	/* Read "tsc" node properties */
768 	child = ofw_bus_find_child(node, "tsc");
769 	if (child != 0 && OF_hasprop(child, "ti,wires")) {
770 		if ((OF_getprop(child, "ti,wires", &cell, sizeof(cell))) > 0)
771 			sc->sc_tsc_wires = fdt32_to_cpu(cell);
772 		if ((OF_getprop(child, "ti,coordinate-readouts", &cell, sizeof(cell))) > 0)
773 			sc->sc_coord_readouts = fdt32_to_cpu(cell);
774 		if ((OF_getprop(child, "ti,x-plate-resistance", &cell, sizeof(cell))) > 0)
775 			sc->sc_x_plate_resistance = fdt32_to_cpu(cell);
776 		if ((OF_getprop(child, "ti,charge-delay", &cell, sizeof(cell))) > 0)
777 			sc->sc_charge_delay = fdt32_to_cpu(cell);
778 		nwire_configs = OF_getencprop_alloc(child, "ti,wire-config",
779 		    sizeof(*wire_configs), (void **)&wire_configs);
780 		if (nwire_configs != sc->sc_tsc_wires) {
781 			device_printf(sc->sc_dev,
782 			    "invalid number of ti,wire-config: %d (should be %d)\n",
783 			    nwire_configs, sc->sc_tsc_wires);
784 			OF_prop_free(wire_configs);
785 			return (EINVAL);
786 		}
787 		err = ti_adc_config_wires(sc, wire_configs, nwire_configs);
788 		OF_prop_free(wire_configs);
789 		if (err)
790 			return (EINVAL);
791 	}
792 
793 	/* Read "adc" node properties */
794 	child = ofw_bus_find_child(node, "adc");
795 	if (child != 0) {
796 		sc->sc_adc_nchannels = OF_getencprop_alloc(child, "ti,adc-channels",
797 		    sizeof(*channels), (void **)&channels);
798 		if (sc->sc_adc_nchannels > 0) {
799 			for (i = 0; i < sc->sc_adc_nchannels; i++)
800 				sc->sc_adc_channels[i] = channels[i];
801 			OF_prop_free(channels);
802 		}
803 	}
804 
805 	/* Sanity check FDT data */
806 	if (sc->sc_tsc_wires + sc->sc_adc_nchannels > TI_ADC_NPINS) {
807 		device_printf(dev, "total number of chanels (%d) is larger than %d\n",
808 		    sc->sc_tsc_wires + sc->sc_adc_nchannels, TI_ADC_NPINS);
809 		return (ENXIO);
810 	}
811 
812 	rid = 0;
813 	sc->sc_mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
814 	    RF_ACTIVE);
815 	if (!sc->sc_mem_res) {
816 		device_printf(dev, "cannot allocate memory window\n");
817 		return (ENXIO);
818 	}
819 
820 	/* Activate the ADC_TSC module. */
821 	err = ti_prcm_clk_enable(TSC_ADC_CLK);
822 	if (err)
823 		return (err);
824 
825 	rid = 0;
826 	sc->sc_irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
827 	    RF_ACTIVE);
828 	if (!sc->sc_irq_res) {
829 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
830 		device_printf(dev, "cannot allocate interrupt\n");
831 		return (ENXIO);
832 	}
833 
834 	if (bus_setup_intr(dev, sc->sc_irq_res, INTR_TYPE_MISC | INTR_MPSAFE,
835 	    NULL, ti_adc_intr, sc, &sc->sc_intrhand) != 0) {
836 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res);
837 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
838 		device_printf(dev, "Unable to setup the irq handler.\n");
839 		return (ENXIO);
840 	}
841 
842 	/* Check the ADC revision. */
843 	rev = ADC_READ4(sc, ADC_REVISION);
844 	device_printf(dev,
845 	    "scheme: %#x func: %#x rtl: %d rev: %d.%d custom rev: %d\n",
846 	    (rev & ADC_REV_SCHEME_MSK) >> ADC_REV_SCHEME_SHIFT,
847 	    (rev & ADC_REV_FUNC_MSK) >> ADC_REV_FUNC_SHIFT,
848 	    (rev & ADC_REV_RTL_MSK) >> ADC_REV_RTL_SHIFT,
849 	    (rev & ADC_REV_MAJOR_MSK) >> ADC_REV_MAJOR_SHIFT,
850 	    rev & ADC_REV_MINOR_MSK,
851 	    (rev & ADC_REV_CUSTOM_MSK) >> ADC_REV_CUSTOM_SHIFT);
852 
853 	reg = ADC_READ4(sc, ADC_CTRL);
854 	ADC_WRITE4(sc, ADC_CTRL, reg | ADC_CTRL_STEP_WP | ADC_CTRL_STEP_ID);
855 
856 	/*
857 	 * Set the ADC prescaler to 2400 if touchscreen is not enabled
858 	 * and to 24 if it is.  This sets the ADC clock to ~10Khz and
859 	 * ~1Mhz respectively (CLK_M_OSC / prescaler).
860 	 */
861 	if (sc->sc_tsc_wires)
862 		ADC_WRITE4(sc, ADC_CLKDIV, 24 - 1);
863 	else
864 		ADC_WRITE4(sc, ADC_CLKDIV, 2400 - 1);
865 
866 	TI_ADC_LOCK_INIT(sc);
867 
868 	ti_adc_idlestep_init(sc);
869 	ti_adc_inputs_init(sc);
870 	ti_adc_sysctl_init(sc);
871 	ti_adc_tsc_init(sc);
872 
873 	TI_ADC_LOCK(sc);
874 	ti_adc_setup(sc);
875 	TI_ADC_UNLOCK(sc);
876 
877 #ifdef EVDEV
878 	if (sc->sc_tsc_wires > 0) {
879 		sc->sc_evdev = evdev_alloc();
880 		evdev_set_name(sc->sc_evdev, device_get_desc(dev));
881 		evdev_set_phys(sc->sc_evdev, device_get_nameunit(dev));
882 		evdev_set_id(sc->sc_evdev, BUS_VIRTUAL, 0, 0, 0);
883 		evdev_support_prop(sc->sc_evdev, INPUT_PROP_DIRECT);
884 		evdev_support_event(sc->sc_evdev, EV_SYN);
885 		evdev_support_event(sc->sc_evdev, EV_ABS);
886 		evdev_support_event(sc->sc_evdev, EV_KEY);
887 
888 		evdev_support_abs(sc->sc_evdev, ABS_X, 0, 0,
889 		    ADC_MAX_VALUE, 0, 0, 0);
890 		evdev_support_abs(sc->sc_evdev, ABS_Y, 0, 0,
891 		    ADC_MAX_VALUE, 0, 0, 0);
892 
893 		evdev_support_key(sc->sc_evdev, BTN_TOUCH);
894 
895 		err = evdev_register(sc->sc_evdev);
896 		if (err) {
897 			device_printf(dev,
898 			    "failed to register evdev: error=%d\n", err);
899 			ti_adc_detach(dev);
900 			return (err);
901 		}
902 
903 		sc->sc_pen_down = 0;
904 		sc->sc_x = -1;
905 		sc->sc_y = -1;
906 	}
907 #endif /* EVDEV */
908 
909 	return (0);
910 }
911 
912 static int
913 ti_adc_detach(device_t dev)
914 {
915 	struct ti_adc_softc *sc;
916 
917 	sc = device_get_softc(dev);
918 
919 	/* Turn off the ADC. */
920 	TI_ADC_LOCK(sc);
921 	ti_adc_reset(sc);
922 	ti_adc_setup(sc);
923 
924 #ifdef EVDEV
925 	evdev_free(sc->sc_evdev);
926 #endif
927 
928 	TI_ADC_UNLOCK(sc);
929 
930 	TI_ADC_LOCK_DESTROY(sc);
931 
932 	if (sc->sc_intrhand)
933 		bus_teardown_intr(dev, sc->sc_irq_res, sc->sc_intrhand);
934 	if (sc->sc_irq_res)
935 		bus_release_resource(dev, SYS_RES_IRQ, 0, sc->sc_irq_res);
936 	if (sc->sc_mem_res)
937 		bus_release_resource(dev, SYS_RES_MEMORY, 0, sc->sc_mem_res);
938 
939 	return (bus_generic_detach(dev));
940 }
941 
942 static device_method_t ti_adc_methods[] = {
943 	DEVMETHOD(device_probe,		ti_adc_probe),
944 	DEVMETHOD(device_attach,	ti_adc_attach),
945 	DEVMETHOD(device_detach,	ti_adc_detach),
946 
947 	DEVMETHOD_END
948 };
949 
950 static driver_t ti_adc_driver = {
951 	"ti_adc",
952 	ti_adc_methods,
953 	sizeof(struct ti_adc_softc),
954 };
955 
956 static devclass_t ti_adc_devclass;
957 
958 DRIVER_MODULE(ti_adc, simplebus, ti_adc_driver, ti_adc_devclass, 0, 0);
959 MODULE_VERSION(ti_adc, 1);
960 MODULE_DEPEND(ti_adc, simplebus, 1, 1, 1);
961