1/*	$NetBSD: nct.c,v 1.5 2021/08/07 16:19:12 thorpej Exp $	*/
2
3/*-
4 * Copyright (c) 2019, 2020 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * Nuvoton NCT5104D
34 *
35 * - GPIO: full support.
36 * - Watchdog: no support.  Watchdog uses GPIO pins.
37 * - UARTS: handled by com driver.  3rd & 4th UARTs use GPIO pins.
38 *
39 * If asked to probe with a wildcard address, we'll only do so if known to
40 * be running on a PC Engines system.  Probe is invasive.
41 *
42 * Register access on Super I/O chips typically involves one or two levels
43 * of indirection, so we try hard to avoid needless register access.
44 */
45
46#include <sys/cdefs.h>
47__KERNEL_RCSID(0, "$NetBSD: nct.c,v 1.5 2021/08/07 16:19:12 thorpej Exp $");
48
49#include <sys/param.h>
50#include <sys/systm.h>
51#include <sys/types.h>
52#include <sys/device.h>
53#include <sys/module.h>
54#include <sys/bus.h>
55#include <sys/gpio.h>
56
57#include <machine/autoconf.h>
58
59#include <dev/isa/isavar.h>
60
61#include <dev/gpio/gpiovar.h>
62
63/*
64 * Hardware interface definition (enough for GPIO only).
65 */
66
67/* I/O basics */
68#define	NCT_IOBASE_A		0x2e
69#define	NCT_IOBASE_B		0x4e
70#define	NCT_IOSIZE		2
71#define	NCT_CHIP_ID_1		0x1061
72#define	NCT_CHIP_ID_2		0xc452	/* PC Engines APU */
73#define	NCT_NUM_PINS		17
74
75/* Enable/disable keys */
76#define NCT_KEY_UNLOCK		0x87
77#define NCT_KEY_LOCK		0xaa
78
79/* I/O ports */
80#define	NCT_PORT_SELECT		0
81#define	NCT_PORT_DATA		1
82
83/* Global registers */
84#define	GD_DEVSEL		0x0007	/* logical device select */
85#define	GD_MULTIFUN		0x001c	/* multi function selection */
86#define		GD_MULTIFUN_GPIO1	0x04	/* clr: gpio1 available */
87#define		GD_MULTIFUN_GPIO0	0x08	/* clr: gpio0 available */
88#define		GD_MULTIFUN_GPIO67	0x10	/* set: gpio67 available */
89#define	GD_GLOBOPT		0x0027	/* global option */
90#define 	GD_GLOBOPT_GPIO67	0x04	/* clr: gpio67 available */
91#define	GD_ID_HIGH		0x0020	/* ID high byte */
92#define	GD_ID_LOW		0x0021	/* ID low byte */
93
94/* Logical device 7 */
95#define	LD7_ENABLE		0x0730	/* GPIO function enable */
96#define		LD7_ENABLE_GPIO0	0x01
97#define		LD7_ENABLE_GPIO1	0x02
98#define		LD7_ENABLE_GPIO67	0x40
99#define	LD7_GPIO0_DIRECTION	0x07e0	/* clr for output, set for input */
100#define	LD7_GPIO0_DATA		0x07e1	/* current status */
101#define	LD7_GPIO0_INVERSION	0x07e2	/* set to invert i/o */
102#define	LD7_GPIO0_STATUS	0x07e3	/* edge detect, reading clears */
103#define	LD7_GPIO1_DIRECTION	0x07e4	/* clr for output, set for input */
104#define	LD7_GPIO1_DATA		0x07e5	/* current status */
105#define	LD7_GPIO1_INVERSION	0x07e6	/* set to invert i/o */
106#define	LD7_GPIO1_STATUS	0x07e7	/* edge detect, reading clears */
107#define	LD7_GPIO67_DIRECTION	0x07f8	/* clr for output, set for input */
108#define	LD7_GPIO67_DATA		0x07f9	/* current status */
109#define	LD7_GPIO67_INVERSION	0x07fa	/* set to invert i/o */
110#define	LD7_GPIO67_STATUS	0x07fb	/* edge detect, reading clears */
111
112/* Logical device 8 */
113#define	LD8_DEVCFG		0x0830	/* WDT/GPIO device config */
114#define	LD8_GPIO0_MULTIFUNC	0x08e0	/* clr: gpio, set: pin unusable */
115#define	LD8_GPIO1_MULTIFUNC	0x08e1	/* clr: gpio, set: pin unusable */
116#define	LD8_GPIO67_MULTIFUNC	0x08e7	/* clr: gpio, set: pin unusable */
117
118/* Logical device 10 */
119#define	LDA_UARTC_ENABLE	0x0a30	/* bit 0: UARTC active */
120
121/* Logical device 11 */
122#define	LDB_UARTD_ENABLE	0x0b30	/* bit 0: UARTD active */
123
124/* Logical device 15 */
125#define	LDF_GPIO0_OUTMODE	0x0fe0	/* clr: push/pull, set: open drain */
126#define	LDF_GPIO1_OUTMODE	0x0fe1	/* clr: push/pull, set: open drain */
127#define	LDF_GPIO67_OUTMODE	0x0fe6	/* clr: push/pull, set: open drain */
128
129/*
130 * Internal GPIO bank description, including register addresses and cached
131 * register content.
132 */
133struct nct_bank {
134	/* Pin descriptions */
135	u_int8_t	nb_firstpin;
136	u_int8_t	nb_numpins;
137	u_int8_t	nb_enabled;
138
139	/* Cached values */
140	u_int8_t	nb_val_dir;
141	u_int8_t	nb_val_inv;
142	u_int8_t	nb_val_mode;
143
144	/* Register addresses */
145	u_int16_t	nb_reg_dir;
146	u_int16_t	nb_reg_data;
147	u_int16_t	nb_reg_inv;
148	u_int16_t	nb_reg_stat;
149	u_int16_t	nb_reg_mode;
150};
151
152/*
153 * Driver instance.
154 */
155struct nct_softc {
156	device_t		sc_dev;			/* MI device */
157	bus_space_tag_t		sc_iot;			/* I/O tag */
158	bus_space_handle_t	sc_ioh;			/* I/O handle */
159	struct gpio_chipset_tag	 sc_gc;			/* GPIO tag */
160	gpio_pin_t		sc_pins[NCT_NUM_PINS];	/* GPIO pin descr. */
161
162	/* Access to the remaining members is covered by sc_lock. */
163	kmutex_t		sc_lock;		/* Serialization */
164	int			sc_curdev;		/* Cur. logical dev */
165	int			sc_curreg;		/* Cur. register */
166	struct nct_bank		sc_bank[3];		/* Bank descriptions */
167};
168
169static void	nct_attach(device_t, device_t, void *);
170static int	nct_detach(device_t, int);
171static void	nct_gpio_ctl(void *, int, int);
172static int	nct_gpio_read(void *, int);
173static void	nct_gpio_write(void *, int, int);
174static int	nct_match(device_t, cfdata_t , void *);
175static u_int8_t	nct_rd(struct nct_softc *, int);
176static struct	nct_bank *nct_sel(struct nct_softc *, int, u_int8_t *);
177static void	nct_wr(struct nct_softc *, int, u_int8_t);
178
179static inline void
180nct_outb(struct nct_softc *sc, int reg, u_int8_t data)
181{
182
183	bus_space_write_1(sc->sc_iot, sc->sc_ioh, reg, data);
184}
185
186static inline u_int8_t
187nct_inb(struct nct_softc *sc, int reg)
188{
189
190	return bus_space_read_1(sc->sc_iot, sc->sc_ioh, reg);
191}
192
193CFATTACH_DECL_NEW(nct,
194		  sizeof(struct nct_softc),
195		  nct_match,
196		  nct_attach,
197		  nct_detach,
198		  NULL);
199
200MODULE(MODULE_CLASS_DRIVER, nct, "gpio");
201
202/*
203 * Module linkage.
204 */
205#ifdef _MODULE
206#include "ioconf.c"
207#endif
208
209static int
210nct_modcmd(modcmd_t cmd, void *priv)
211{
212	int error = 0;
213
214	switch (cmd) {
215	case MODULE_CMD_INIT:
216#ifdef _MODULE
217		error = config_init_component(cfdriver_ioconf_nct,
218		    cfattach_ioconf_nct, cfdata_ioconf_nct);
219#endif
220		return error;
221	case MODULE_CMD_FINI:
222#ifdef _MODULE
223		error = config_fini_component(cfdriver_ioconf_nct,
224		    cfattach_ioconf_nct, cfdata_ioconf_nct);
225#endif
226		return error;
227	default:
228		return ENOTTY;
229	}
230}
231
232/*
233 * Probe for device.
234 */
235static int
236nct_match(device_t parent, cfdata_t match, void *aux)
237{
238	int ioaddrs[2] = { 0x2e, 0x4e };
239	struct isa_attach_args *ia = aux;
240	bus_space_handle_t ioh;
241	int nioaddr, i;
242	u_int8_t low, high;
243	u_int16_t id;
244	const char *vendor;
245
246	/*
247	 * Allow override of I/O base address.  If no I/O base address is
248	 * provided, proceed to probe if running on a PC Engines system.
249	 */
250	if (ia->ia_nio > 0 && ia->ia_io[0].ir_addr != ISA_UNKNOWN_PORT) {
251		ioaddrs[0] = ia->ia_io[0].ir_addr;
252		nioaddr = 1;
253	} else {
254		vendor = pmf_get_platform("system-vendor");
255		if (vendor != NULL && strstr(vendor, "PC Engines") != NULL) {
256			nioaddr = __arraycount(ioaddrs);
257		} else {
258			nioaddr = 0;
259		}
260	}
261
262	/*
263	 * Probe at the selected addresses, if any.
264	 */
265	for (i = 0; i < nioaddr; i++) {
266		if (bus_space_map(ia->ia_iot, ioaddrs[i], NCT_IOSIZE, 0,
267		    &ioh) != 0) {
268		    continue;
269		}
270                /* Unlock chip */
271		bus_space_write_1(ia->ia_iot, ioh, NCT_PORT_SELECT,
272		    NCT_KEY_UNLOCK);
273		bus_space_write_1(ia->ia_iot, ioh, NCT_PORT_SELECT,
274		    NCT_KEY_UNLOCK);
275		/* Read ID */
276		bus_space_write_1(ia->ia_iot, ioh, NCT_PORT_SELECT, GD_ID_LOW);
277		low = bus_space_read_1(ia->ia_iot, ioh, NCT_PORT_DATA);
278		bus_space_write_1(ia->ia_iot, ioh, NCT_PORT_SELECT, GD_ID_HIGH);
279		high = bus_space_read_1(ia->ia_iot, ioh, NCT_PORT_DATA);
280		id = (u_int16_t)low | ((u_int16_t)high << 8);
281		bus_space_unmap(ia->ia_iot, ioh, NCT_IOSIZE);
282		if (id == NCT_CHIP_ID_1 || id == NCT_CHIP_ID_2) {
283			ia->ia_nirq = 0;
284			ia->ia_ndrq = 0;
285			ia->ia_niomem = 0;
286			ia->ia_nio = 1;
287			ia->ia_io[0].ir_size = NCT_IOSIZE;
288			ia->ia_io[0].ir_addr = ioaddrs[i];
289			return 1;
290		}
291	}
292	return 0;
293}
294
295/*
296 * Attach device instance.
297 */
298static void
299nct_attach(device_t parent, device_t self, void *aux)
300{
301	struct nct_softc *sc = device_private(self);
302	struct isa_attach_args *ia = aux;
303	struct gpiobus_attach_args gba;
304	struct nct_bank *nb;
305	u_int8_t multifun, enable;
306	int i, j;
307
308	/*
309	 * Set up register space and basics of our state.
310	 */
311	if (bus_space_map(ia->ia_iot, ia->ia_io[0].ir_addr,
312	    ia->ia_io[0].ir_size, 0, &sc->sc_ioh) != 0) {
313		aprint_normal(": can't map i/o space\n");
314		return;
315	}
316	aprint_normal(": Nuvoton NCT5104D GPIO\n");
317	sc->sc_dev = self;
318	sc->sc_iot = ia->ia_iot;
319	sc->sc_curdev = -1;
320	sc->sc_curreg = -1;
321
322        /*
323         * All pin access is funneled through a common, indirect register
324         * interface.  The gpio framework doesn't serialize calls to our
325         * access methods, so do it internally.  This is likely such a
326         * common requirement that it should be factored out as is done for
327         * audio devices, allowing the driver to specify the appropriate
328         * locks.  Anyhow, acquire the lock immediately to pacify locking
329         * assertions.
330         */
331        mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM);
332	mutex_spin_enter(&sc->sc_lock);
333
334        /*
335         * Disable watchdog timer and GPIO alternate I/O mapping.
336         */
337        nct_wr(sc, LD8_DEVCFG, 0);
338
339	/*
340	 * The BIOS doesn't set things up the way we want.  Pfft.
341	 * Enable all GPIO0/GPIO1 pins.
342	 */
343	multifun = nct_rd(sc, GD_MULTIFUN);
344	nct_wr(sc, GD_MULTIFUN,
345	    multifun & ~(GD_MULTIFUN_GPIO0 | GD_MULTIFUN_GPIO1));
346	nct_wr(sc, LDA_UARTC_ENABLE, 0);
347	nct_wr(sc, LD8_GPIO0_MULTIFUNC, 0);
348	nct_wr(sc, LDB_UARTD_ENABLE, 0);
349	nct_wr(sc, LD8_GPIO1_MULTIFUNC, 0);
350	multifun = nct_rd(sc, GD_MULTIFUN);
351	enable = nct_rd(sc, LD7_ENABLE) | LD7_ENABLE_GPIO0 | LD7_ENABLE_GPIO1;
352
353	nb = &sc->sc_bank[0];
354	nb->nb_firstpin = 0;
355	nb->nb_numpins = 8;
356	nb->nb_enabled = 0xff;
357	nb->nb_reg_dir = LD7_GPIO0_DIRECTION;
358	nb->nb_reg_data = LD7_GPIO0_DATA;
359	nb->nb_reg_inv = LD7_GPIO0_INVERSION;
360	nb->nb_reg_stat = LD7_GPIO0_STATUS;
361	nb->nb_reg_mode = LDF_GPIO0_OUTMODE;
362
363	nb = &sc->sc_bank[1];
364	nb->nb_firstpin = 8;
365	nb->nb_numpins = 8;
366	nb->nb_enabled = 0xff;
367	nb->nb_reg_dir = LD7_GPIO1_DIRECTION;
368	nb->nb_reg_data = LD7_GPIO1_DATA;
369	nb->nb_reg_inv = LD7_GPIO1_INVERSION;
370	nb->nb_reg_stat = LD7_GPIO1_STATUS;
371	nb->nb_reg_mode = LDF_GPIO1_OUTMODE;
372
373	nb = &sc->sc_bank[2];
374	nb->nb_firstpin = 16;
375	nb->nb_numpins = 1;
376	nb->nb_reg_dir = LD7_GPIO67_DIRECTION;
377	nb->nb_reg_data = LD7_GPIO67_DATA;
378	nb->nb_reg_stat = LD7_GPIO67_STATUS;
379	nb->nb_reg_mode = LDF_GPIO67_OUTMODE;
380	if ((multifun & GD_MULTIFUN_GPIO67) != 0 &&
381	    (nct_rd(sc, GD_GLOBOPT) & GD_GLOBOPT_GPIO67) == 0) {
382		nct_wr(sc, LD8_GPIO67_MULTIFUNC, 0);
383		nb->nb_enabled = 0x01;
384		enable |= LD7_ENABLE_GPIO67;
385	} else {
386		sc->sc_bank[2].nb_enabled = 0;
387	}
388
389	/*
390	 * Display enabled pins and enable GPIO devices accordingly.
391	 */
392	nct_wr(sc, LD7_ENABLE, enable);
393	mutex_spin_exit(&sc->sc_lock);
394
395	aprint_normal_dev(self,
396	    "enabled pins: GPIO0(%02x) GPIO1(%02x) GPIO67(%01x)\n",
397	    (unsigned)sc->sc_bank[0].nb_enabled,
398	    (unsigned)sc->sc_bank[1].nb_enabled,
399	    (unsigned)sc->sc_bank[2].nb_enabled);
400
401	/*
402	 * Fill pin descriptions and initialize registers.
403	 */
404	memset(sc->sc_pins, 0, sizeof(sc->sc_pins));
405	for (i = 0; i < __arraycount(sc->sc_bank); i++) {
406		nb = &sc->sc_bank[i];
407		mutex_spin_enter(&sc->sc_lock);
408		nb->nb_val_dir = nct_rd(sc, nb->nb_reg_dir);
409		nb->nb_val_inv = nct_rd(sc, nb->nb_reg_inv);
410		nb->nb_val_mode = nct_rd(sc, nb->nb_reg_mode);
411		mutex_spin_exit(&sc->sc_lock);
412		for (j = 0; j < nb->nb_numpins; j++) {
413			gpio_pin_t *pin = &sc->sc_pins[nb->nb_firstpin + j];
414			pin->pin_num = nb->nb_firstpin + j;
415			/* Skip pin if not configured as GPIO. */
416			if ((nb->nb_enabled & (1 << j)) == 0) {
417				continue;
418			}
419			pin->pin_caps =
420			    GPIO_PIN_INPUT | GPIO_PIN_OUTPUT |
421			    GPIO_PIN_OPENDRAIN |
422			    GPIO_PIN_PUSHPULL | GPIO_PIN_TRISTATE |
423			    GPIO_PIN_INVIN | GPIO_PIN_INVOUT;
424			pin->pin_flags =
425			    GPIO_PIN_INPUT | GPIO_PIN_OPENDRAIN;
426			nct_gpio_ctl(sc, pin->pin_num, pin->pin_flags);
427			pin->pin_state = nct_gpio_read(sc, pin->pin_num);
428		}
429	}
430
431	/*
432	 * Attach to gpio framework, and attach all pins unconditionally.
433	 * If the pins are disabled, we'll ignore any access later.
434	 */
435	sc->sc_gc.gp_cookie = sc;
436	sc->sc_gc.gp_pin_read = nct_gpio_read;
437	sc->sc_gc.gp_pin_write = nct_gpio_write;
438	sc->sc_gc.gp_pin_ctl = nct_gpio_ctl;
439
440	gba.gba_gc = &sc->sc_gc;
441	gba.gba_pins = sc->sc_pins;
442	gba.gba_npins = NCT_NUM_PINS;
443
444	(void)config_found(sc->sc_dev, &gba, gpiobus_print, CFARGS_NONE);
445}
446
447/*
448 * Detach device instance.
449 */
450static int
451nct_detach(device_t self, int flags)
452{
453	struct nct_softc *sc = device_private(self);
454
455	bus_space_unmap(sc->sc_iot, sc->sc_ioh, NCT_IOSIZE);
456	mutex_destroy(&sc->sc_lock);
457	return 0;
458}
459
460/*
461 * Read byte from specified register.
462 */
463static u_int8_t
464nct_rd(struct nct_softc *sc, int reg)
465{
466	int dev;
467
468	KASSERT(mutex_owned(&sc->sc_lock));
469
470	dev = reg >> 8;
471	reg &= 0xff;
472
473	if (dev != sc->sc_curdev && dev != 0x00) {
474		sc->sc_curdev = dev;
475		sc->sc_curreg = reg;
476		nct_outb(sc, NCT_PORT_SELECT, GD_DEVSEL);
477		nct_outb(sc, NCT_PORT_DATA, dev);
478		nct_outb(sc, NCT_PORT_SELECT, reg);
479		return nct_inb(sc, NCT_PORT_DATA);
480	} else if (reg != sc->sc_curreg) {
481		sc->sc_curreg = reg;
482		nct_outb(sc, NCT_PORT_SELECT, reg);
483		return nct_inb(sc, NCT_PORT_DATA);
484	} else {
485		return nct_inb(sc, NCT_PORT_DATA);
486	}
487}
488
489/*
490 * Write byte to specified register.
491 */
492static void
493nct_wr(struct nct_softc *sc, int reg, u_int8_t data)
494{
495	int dev;
496
497	KASSERT(mutex_owned(&sc->sc_lock));
498
499	dev = reg >> 8;
500	reg &= 0xff;
501
502	if (dev != sc->sc_curdev && dev != 0x00) {
503		sc->sc_curdev = dev;
504		sc->sc_curreg = reg;
505		nct_outb(sc, NCT_PORT_SELECT, GD_DEVSEL);
506		nct_outb(sc, NCT_PORT_DATA, dev);
507		nct_outb(sc, NCT_PORT_SELECT, reg);
508		nct_outb(sc, NCT_PORT_DATA, data);
509	} else if (reg != sc->sc_curreg) {
510		sc->sc_curreg = reg;
511		nct_outb(sc, NCT_PORT_SELECT, reg);
512		nct_outb(sc, NCT_PORT_DATA, data);
513	} else {
514		nct_outb(sc, NCT_PORT_DATA, data);
515	}
516}
517
518/*
519 * Given pin number, return bank and pin mask.  This alters no state and so
520 * can safely be called without the mutex held.
521 */
522static struct nct_bank *
523nct_sel(struct nct_softc *sc, int pin, u_int8_t *mask)
524{
525	struct nct_bank *nb;
526
527	KASSERT(pin >= 0 && pin < NCT_NUM_PINS);
528	nb = &sc->sc_bank[pin >> 3];
529	KASSERT(pin >= nb->nb_firstpin);
530	KASSERT((pin & 7) < nb->nb_numpins);
531	*mask = (u_int8_t)(1 << (pin & 7)) & nb->nb_enabled;
532	return nb;
533}
534
535/*
536 * GPIO hook: read pin.
537 */
538static int
539nct_gpio_read(void *arg, int pin)
540{
541	struct nct_softc *sc = arg;
542	struct nct_bank *nb;
543	u_int8_t data, mask;
544	int rv = GPIO_PIN_LOW;
545
546	nb = nct_sel(sc, pin, &mask);
547	if (__predict_true(mask != 0)) {
548		mutex_spin_enter(&sc->sc_lock);
549		data = nct_rd(sc, nb->nb_reg_data);
550		if ((data & mask) != 0) {
551			rv = GPIO_PIN_HIGH;
552		}
553		mutex_spin_exit(&sc->sc_lock);
554	}
555	return rv;
556}
557
558/*
559 * GPIO hook: write pin.
560 */
561static void
562nct_gpio_write(void *arg, int pin, int val)
563{
564	struct nct_softc *sc = arg;
565	struct nct_bank *nb;
566	u_int8_t data, mask;
567
568	nb = nct_sel(sc, pin, &mask);
569	if (__predict_true(mask != 0)) {
570		mutex_spin_enter(&sc->sc_lock);
571		data = nct_rd(sc, nb->nb_reg_data);
572		if (val == GPIO_PIN_LOW) {
573			data &= ~mask;
574		} else if (val == GPIO_PIN_HIGH) {
575			data |= mask;
576		}
577		nct_wr(sc, nb->nb_reg_data, data);
578		mutex_spin_exit(&sc->sc_lock);
579	}
580}
581
582/*
583 * GPIO hook: change pin parameters.
584 */
585static void
586nct_gpio_ctl(void *arg, int pin, int flg)
587{
588	struct nct_softc *sc = arg;
589	struct nct_bank *nb;
590	u_int8_t data, mask;
591
592	nb = nct_sel(sc, pin, &mask);
593	if (__predict_false(mask == 0)) {
594		return;
595	}
596
597	/*
598	 * Set input direction early to avoid perturbation.
599	 */
600	mutex_spin_enter(&sc->sc_lock);
601	data = nb->nb_val_dir;
602	if ((flg & (GPIO_PIN_INPUT | GPIO_PIN_TRISTATE)) != 0) {
603		data |= mask;
604	}
605	if (data != nb->nb_val_dir) {
606		nct_wr(sc, nb->nb_reg_dir, data);
607		nb->nb_val_dir = data;
608	}
609
610	/*
611	 * Set inversion.
612	 */
613	data = nb->nb_val_inv;
614	if ((flg & (GPIO_PIN_OUTPUT | GPIO_PIN_INVOUT)) ==
615	             (GPIO_PIN_OUTPUT | GPIO_PIN_INVOUT) ||
616            (flg & (GPIO_PIN_INPUT | GPIO_PIN_INVIN)) ==
617  	             (GPIO_PIN_INPUT | GPIO_PIN_INVIN)) {
618		data |= mask;
619	} else {
620		data &= ~mask;
621	}
622	if (data != nb->nb_val_inv) {
623		nct_wr(sc, nb->nb_reg_inv, data);
624		nb->nb_val_inv = data;
625	}
626
627	/*
628	 * Set drain mode.
629	 */
630	data = nb->nb_val_mode;
631	if ((flg & GPIO_PIN_PUSHPULL) != 0) {
632		data |= mask;
633	} else /* GPIO_PIN_OPENDRAIN */ {
634		data &= ~mask;
635	}
636	if (data != nb->nb_val_mode) {
637		nct_wr(sc, nb->nb_reg_mode, data);
638		nb->nb_val_mode = data;
639	}
640
641	/*
642	 * Set output direction late to avoid perturbation.
643	 */
644	data = nb->nb_val_dir;
645	if ((flg & (GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE)) == GPIO_PIN_OUTPUT) {
646		data &= ~mask;
647	}
648	if (data != nb->nb_val_dir) {
649		nct_wr(sc, nb->nb_reg_dir, data);
650		nb->nb_val_dir = data;
651	}
652	mutex_spin_exit(&sc->sc_lock);
653}
654