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      1 /* $Id: imx23_pinctrl.c,v 1.6 2021/08/07 16:18:44 thorpej Exp $ */
      2 
      3 /*
      4 * Copyright (c) 2013 The NetBSD Foundation, Inc.
      5 * All rights reserved.
      6 *
      7 * This code is derived from software contributed to The NetBSD Foundation
      8 * by Petri Laakso.
      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 #include <sys/param.h>
     33 #include <sys/types.h>
     34 #include <sys/bus.h>
     35 #include <sys/cdefs.h>
     36 #include <sys/device.h>
     37 #include <sys/errno.h>
     38 #include <sys/gpio.h>
     39 
     40 #include <dev/gpio/gpiovar.h>
     41 
     42 #include <arm/imx/imx23_pinctrlreg.h>
     43 #include <arm/imx/imx23_pinctrlvar.h>
     44 #include <arm/imx/imx23var.h>
     45 
     46 #define GPIO_PINS 96
     47 
     48 typedef struct imx23_pinctrl_softc {
     49 	device_t sc_dev;
     50 	bus_space_tag_t sc_iot;
     51 	bus_space_handle_t sc_hdl;
     52 	struct gpio_chipset_tag gc;
     53 	gpio_pin_t pins[GPIO_PINS];
     54 } *imx23_pinctrl_softc_t;
     55 
     56 static int	imx23_pinctrl_match(device_t, cfdata_t, void *);
     57 static void	imx23_pinctrl_attach(device_t, device_t, void *);
     58 static int	imx23_pinctrl_activate(device_t, enum devact);
     59 
     60 #if notyet
     61 static void     imx23_pinctrl_reset(struct imx23_pinctrl_softc *);
     62 #endif
     63 static void     imx23_pinctrl_init(struct imx23_pinctrl_softc *);
     64 
     65 static	int	imx23_pinctrl_gp_gc_open(void *, device_t);
     66 static	void	imx23_pinctrl_gp_gc_close(void *, device_t);
     67 static	int	imx23_pinctrl_gp_pin_read(void *, int);
     68 static	void	imx23_pinctrl_gp_pin_write(void *, int, int);
     69 static	void	imx23_pinctrl_gp_pin_ctl(void *, int, int);
     70 
     71 static imx23_pinctrl_softc_t _sc = NULL;
     72 
     73 CFATTACH_DECL3_NEW(imx23_pinctrl,
     74         sizeof(struct imx23_pinctrl_softc),
     75         imx23_pinctrl_match,
     76         imx23_pinctrl_attach,
     77         NULL,
     78         imx23_pinctrl_activate,
     79         NULL,
     80         NULL,
     81         0
     82 );
     83 
     84 #define GPIO_PIN_CAP (GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_INOUT | \
     85 		GPIO_PIN_PULLUP | GPIO_PIN_SET)
     86 
     87 /*
     88  * Supported capabilities for each GPIO pin.
     89  */
     90 const static int pin_caps[GPIO_PINS] = {
     91 	/*
     92 	 * HW_PINCTRL_MUXSEL0
     93 	 */
     94 	/* PIN 0 */
     95 	GPIO_PIN_CAP,
     96 	/* PIN 1 */
     97 	GPIO_PIN_CAP,
     98 	/* PIN 2 */
     99 	GPIO_PIN_CAP,
    100 	/* PIN 3 */
    101 	GPIO_PIN_CAP,
    102 	/* PIN 4 */
    103 	GPIO_PIN_CAP,
    104 	/* PIN 5 */
    105 	GPIO_PIN_CAP,
    106 	/* PIN 6 */
    107 	GPIO_PIN_CAP,
    108 	/* PIN 7 */
    109 	GPIO_PIN_CAP,
    110 	/* PIN 8 */
    111 	GPIO_PIN_CAP,
    112 	/* PIN 9 */
    113 	GPIO_PIN_CAP,
    114 	/* PIN 10 */
    115 	GPIO_PIN_CAP,
    116 	/* PIN 11 */
    117 	GPIO_PIN_CAP,
    118 	/* PIN 12 */
    119 	GPIO_PIN_CAP,
    120 	/* PIN 13 */
    121 	GPIO_PIN_CAP,
    122 	/* PIN 14 */
    123 	GPIO_PIN_CAP,
    124 	/* PIN 15 */
    125 	GPIO_PIN_CAP,
    126 	/*
    127 	 * HW_PINCTRL_MUXSEL1
    128 	 */
    129 	/* PIN 16 */
    130 	GPIO_PIN_CAP,
    131 	/* PIN 17 */
    132 	0,		/* Reserved for powering OLinuXino MAXI/MINI USB hub. */
    133 	/* PIN 18 */
    134 	GPIO_PIN_CAP,
    135 	/* PIN 19 */
    136 	GPIO_PIN_CAP,
    137 	/* PIN 20 */
    138 	GPIO_PIN_CAP,
    139 	/* PIN 21 */
    140 	GPIO_PIN_CAP,
    141 	/* PIN 22 */
    142 	GPIO_PIN_CAP,
    143 	/* PIN 23 */
    144 	GPIO_PIN_CAP,
    145 	/* PIN 24 */
    146 	GPIO_PIN_CAP,
    147 	/* PIN 25 */
    148 	GPIO_PIN_CAP,
    149 	/* PIN 26 */
    150 	GPIO_PIN_CAP,
    151 	/* PIN 27 */
    152 	GPIO_PIN_CAP,
    153 	/* PIN 28 */
    154 	GPIO_PIN_CAP,
    155 	/* PIN 29 */
    156 	GPIO_PIN_CAP,
    157 	/* PIN 30 */
    158 	GPIO_PIN_CAP,
    159 	/* PIN 31 */
    160 	GPIO_PIN_CAP,
    161 	/*
    162 	 * HW_PINCTRL_MUXSEL2
    163 	 */
    164 	/* PIN 32 */
    165 	GPIO_PIN_CAP,
    166 	/* PIN 33 */
    167 	GPIO_PIN_CAP,
    168 	/* PIN 34 */
    169 	GPIO_PIN_CAP,
    170 	/* PIN 35 */
    171 	GPIO_PIN_CAP,
    172 	/* PIN 36 */
    173 	GPIO_PIN_CAP,
    174 	/* PIN 37 */
    175 	GPIO_PIN_CAP,
    176 	/* PIN 38 */
    177 	GPIO_PIN_CAP,
    178 	/* PIN 39 */
    179 	GPIO_PIN_CAP,
    180 	/* PIN 40 */
    181 	GPIO_PIN_CAP,
    182 	/* PIN 41 */
    183 	GPIO_PIN_CAP,
    184 	/* PIN 42 */
    185 	GPIO_PIN_CAP,
    186 	/* PIN 43 */
    187 	GPIO_PIN_CAP,
    188 	/* PIN 44 */
    189 	GPIO_PIN_CAP,
    190 	/* PIN 45 */
    191 	GPIO_PIN_CAP,
    192 	/* PIN 46 */
    193 	GPIO_PIN_CAP,
    194 	/* PIN 47 */
    195 	GPIO_PIN_CAP,
    196 	/*
    197 	 * HW_PINCTRL_MUXSEL3
    198 	 */
    199 	/* PIN 48 */
    200 	GPIO_PIN_CAP,
    201 	/* PIN 49 */
    202 	GPIO_PIN_CAP,
    203 	/* PIN 50 */
    204 	GPIO_PIN_CAP,
    205 	/* PIN 51 */
    206 	GPIO_PIN_CAP,
    207 	/* PIN 52 */
    208 	GPIO_PIN_CAP,
    209 	/* PIN 53 */
    210 	GPIO_PIN_CAP,
    211 	/* PIN 54 */
    212 	GPIO_PIN_CAP,
    213 	/* PIN 55 */
    214 	GPIO_PIN_CAP,
    215 	/* PIN 56 */
    216 	GPIO_PIN_CAP,
    217 	/* PIN 57 */
    218 	GPIO_PIN_CAP,
    219 	/* PIN 58 */
    220 	GPIO_PIN_CAP,
    221 	/* PIN 59 */
    222 	GPIO_PIN_CAP,
    223 	/* PIN 60 */
    224 	GPIO_PIN_CAP,
    225 	/* PIN 61 */
    226 	GPIO_PIN_CAP,
    227 	/* PIN 62 */
    228 	GPIO_PIN_CAP,
    229 	/* PIN 63 */
    230 	0,		/* Reserved. */
    231 	/*
    232 	 * HW_PINCTRL_MUXSEL4
    233 	 */
    234 	/* PIN 64 */
    235 	GPIO_PIN_CAP,
    236 	/* PIN 65 */
    237 	GPIO_PIN_CAP,
    238 	/* PIN 66 */
    239 	GPIO_PIN_CAP,
    240 	/* PIN 67 */
    241 	GPIO_PIN_CAP,
    242 	/* PIN 68 */
    243 	GPIO_PIN_CAP,
    244 	/* PIN 69 */
    245 	GPIO_PIN_CAP,
    246 	/* PIN 70 */
    247 	GPIO_PIN_CAP,
    248 	/* PIN 71 */
    249 	GPIO_PIN_CAP,
    250 	/* PIN 72 */
    251 	GPIO_PIN_CAP,
    252 	/* PIN 73 */
    253 	0,		/* From this on reserved for EMI (DRAM) pins. */
    254 	/* PIN 74 */
    255 	0,
    256 	/* PIN 75 */
    257 	0,
    258 	/* PIN 76 */
    259 	0,
    260 	/* PIN 77 */
    261 	0,
    262 	/* PIN 78 */
    263 	0,
    264 	/* PIN 79 */
    265 	0,
    266 	/*
    267 	 * HW_PINCTRL_MUXSEL5
    268 	 */
    269 	/* PIN 80 */
    270 	0,
    271 	/* PIN 81 */
    272 	0,
    273 	/* PIN 82 */
    274 	0,
    275 	/* PIN 83 */
    276 	0,
    277 	/* PIN 84 */
    278 	0,
    279 	/* PIN 85 */
    280 	0,
    281 	/* PIN 86 */
    282 	0,
    283 	/* PIN 87 */
    284 	0,
    285 	/* PIN 88 */
    286 	0,
    287 	/* PIN 89 */
    288 	0,
    289 	/* PIN 90 */
    290 	0,
    291 	/* PIN 91 */
    292 	0,
    293 	/* PIN 92 */
    294 	0,
    295 	/* PIN 93 */
    296 	0,
    297 	/* PIN 94 */
    298 	0,
    299 	/* PIN 95 */
    300 	0
    301 };
    302 
    303 #define PINCTRL_RD(sc, reg)						\
    304 	bus_space_read_4(sc->sc_iot, sc->sc_hdl, (reg))
    305 #define PINCTRL_WR(sc, reg, val)					\
    306 	bus_space_write_4(sc->sc_iot, sc->sc_hdl, (reg), (val))
    307 
    308 /*
    309  * Macros to map pin numbers to registers and bit fields.
    310  */
    311 #define MUXSEL_REG_SIZE	0x10
    312 #define PIN2MUXSEL_REG(pin)						\
    313 	((pin / 16) * MUXSEL_REG_SIZE + HW_PINCTRL_MUXSEL0)
    314 #define PIN2MUXSEL_SET_REG(pin)						\
    315 	((pin / 16) * MUXSEL_REG_SIZE + HW_PINCTRL_MUXSEL0_SET)
    316 #define PIN2MUXSEL_CLR_REG(pin)						\
    317 	((pin / 16) * MUXSEL_REG_SIZE + HW_PINCTRL_MUXSEL0_CLR)
    318 #define PIN2MUXSEL_MASK(pin)	(3<<(pin % 16 * 2))
    319 
    320 #define DRIVE_REG_SIZE	0x10
    321 #define PIN2DRIVE_REG(pin)						\
    322 	((pin / 8) * DRIVE_REG_SIZE + HW_PINCTRL_DRIVE0)
    323 #define PIN2DRIVE_SET_REG(pin)						\
    324 	((pin / 8) * DRIVE_REG_SIZE + HW_PINCTRL_DRIVE0_SET)
    325 #define PIN2DRIVE_CLR_REG(pin)						\
    326 	((pin / 8) * DRIVE_REG_SIZE + HW_PINCTRL_DRIVE0_CLR)
    327 #define PIN2DRIVE_MASK(pin)	(3<<(pin % 8 * 4))
    328 
    329 #define PULL_REG_SIZE	0x10
    330 #define PIN2PULL_REG(pin)						\
    331 	((pin / 32) * PULL_REG_SIZE + HW_PINCTRL_PULL0)
    332 #define PIN2PULL_SET_REG(pin)						\
    333 	((pin / 32) * PULL_REG_SIZE + HW_PINCTRL_PULL0_SET)
    334 #define PIN2PULL_CLR_REG(pin)						\
    335 	((pin / 32) * PULL_REG_SIZE + HW_PINCTRL_PULL0_CLR)
    336 #define PIN2PULL_MASK(pin)	(1<<(pin % 32))
    337 
    338 #define DOUT_REG_SIZE	0x10
    339 #define PIN2DOUT_REG(pin)						\
    340 	((pin / 32) * DOUT_REG_SIZE + HW_PINCTRL_DOUT0)
    341 #define PIN2DOUT_SET_REG(pin)						\
    342 	((pin / 32) * DOUT_REG_SIZE + HW_PINCTRL_DOUT0_SET)
    343 #define PIN2DOUT_CLR_REG(pin)						\
    344 	((pin / 32) * DOUT_REG_SIZE + HW_PINCTRL_DOUT0_CLR)
    345 #define PIN2DOUT_MASK(pin)	(1<<(pin % 32))
    346 
    347 #define DIN_REG_SIZE	0x10
    348 #define PIN2DIN_REG(pin)	((pin / 32) * DIN_REG_SIZE + HW_PINCTRL_DIN0)
    349 #define PIN2DIN_MASK(pin)	(1<<(pin % 32))
    350 
    351 #define DOE_REG_SIZE	0x10
    352 #define PIN2DOE_REG(pin)						\
    353 	((pin / 32) * DOE_REG_SIZE + HW_PINCTRL_DOE0)
    354 #define PIN2DOE_SET_REG(pin)						\
    355 	((pin / 32) * DOE_REG_SIZE + HW_PINCTRL_DOE0_SET)
    356 #define PIN2DOE_CLR_REG(pin)						\
    357 	((pin / 32) * DOE_REG_SIZE + HW_PINCTRL_DOE0_CLR)
    358 #define PIN2DOE_MASK(pin)	(1<<(pin % 32))
    359 
    360 #define DRIVE_STRENGTH_4MA	0
    361 #define DRIVE_STRENGTH_8MA	1
    362 #define DRIVE_STRENGTH_12MA	2
    363 
    364 #define MUXEL_GPIO_MODE	3
    365 
    366 #define PINCTRL_SOFT_RST_LOOP 455 /* At least 1 us ... */
    367 
    368 static int
    369 imx23_pinctrl_match(device_t parent, cfdata_t match, void *aux)
    370 {
    371 	struct apb_attach_args *aa = aux;
    372 
    373 	if ((aa->aa_addr == HW_PINCTRL_BASE) &&
    374 	    (aa->aa_size == HW_PINCTRL_SIZE))
    375 		return 1;
    376 
    377 	return 0;
    378 }
    379 
    380 static void
    381 imx23_pinctrl_attach(device_t parent, device_t self, void *aux)
    382 {
    383 	struct imx23_pinctrl_softc *sc = device_private(self);
    384 	struct apb_attach_args *aa = aux;
    385 	static int imx23_pinctrl_attached = 0;
    386 
    387 	sc->sc_dev = self;
    388 	sc->sc_iot = aa->aa_iot;
    389 
    390 	if (imx23_pinctrl_attached) {
    391 		aprint_error_dev(sc->sc_dev, "already attached\n");
    392 		return;
    393 	}
    394 
    395 	if (bus_space_map(sc->sc_iot, aa->aa_addr, aa->aa_size, 0,
    396 	    &sc->sc_hdl)) {
    397 		aprint_error_dev(sc->sc_dev, "Unable to map bus space\n");
    398 		return;
    399 	}
    400 
    401 #if notyet
    402 	imx23_pinctrl_reset(sc);
    403 #endif
    404 
    405 	imx23_pinctrl_init(sc);
    406 
    407 	aprint_normal(": PIN MUX & GPIO\n");
    408 
    409 	/* Set pin capabilities. */
    410 	int i;
    411 	for(i = 0; i < GPIO_PINS; i++) {
    412 		sc->pins[i].pin_caps = pin_caps[i];
    413 	}
    414 
    415 	imx23_pinctrl_attached = 1;
    416 
    417 	sc->gc.gp_cookie = sc;
    418 	sc->gc.gp_gc_open = imx23_pinctrl_gp_gc_open;
    419 	sc->gc.gp_gc_close = imx23_pinctrl_gp_gc_close;
    420 	sc->gc.gp_pin_read = imx23_pinctrl_gp_pin_read;
    421 	sc->gc.gp_pin_write = imx23_pinctrl_gp_pin_write;
    422 	sc->gc.gp_pin_ctl = imx23_pinctrl_gp_pin_ctl;
    423 
    424 	struct gpiobus_attach_args gpiobus_aa;
    425 	gpiobus_aa.gba_gc = &sc->gc;
    426 	gpiobus_aa.gba_npins = GPIO_PINS;
    427 	gpiobus_aa.gba_pins = sc->pins;
    428 
    429 	config_found(self, &gpiobus_aa, gpiobus_print, CFARGS_NONE);
    430 
    431 	return;
    432 }
    433 
    434 static int
    435 imx23_pinctrl_activate(device_t self, enum devact act)
    436 {
    437 
    438 	return EOPNOTSUPP;
    439 }
    440 
    441 static void
    442 imx23_pinctrl_init(struct imx23_pinctrl_softc *sc)
    443 {
    444 	_sc = sc;
    445 	return;
    446 }
    447 
    448 #if notyet
    449 /*
    450  * Inspired by i.MX23 RM "39.3.10 Correct Way to Soft Reset a Block"
    451  */
    452 static void
    453 imx23_pinctrl_reset(struct imx23_pinctrl_softc *sc)
    454 {
    455         unsigned int loop;
    456 
    457         /* Prepare for soft-reset by making sure that SFTRST is not currently
    458          * asserted. Also clear CLKGATE so we can wait for its assertion below.
    459          */
    460         PINCTRL_WR(sc, HW_PINCTRL_CTRL_CLR, HW_PINCTRL_CTRL_SFTRST);
    461 
    462         /* Wait at least a microsecond for SFTRST to deassert. */
    463         loop = 0;
    464         while ((PINCTRL_RD(sc, HW_PINCTRL_CTRL) & HW_PINCTRL_CTRL_SFTRST) ||
    465             (loop < PINCTRL_SOFT_RST_LOOP))
    466                 loop++;
    467 
    468         /* Clear CLKGATE so we can wait for its assertion below. */
    469         PINCTRL_WR(sc, HW_PINCTRL_CTRL_CLR, HW_PINCTRL_CTRL_CLKGATE);
    470 
    471         /* Soft-reset the block. */
    472         PINCTRL_WR(sc, HW_PINCTRL_CTRL_SET, HW_PINCTRL_CTRL_SFTRST);
    473 
    474         /* Wait until clock is in the gated state. */
    475         while (!(PINCTRL_RD(sc, HW_PINCTRL_CTRL) & HW_PINCTRL_CTRL_CLKGATE));
    476 
    477         /* Bring block out of reset. */
    478         PINCTRL_WR(sc, HW_PINCTRL_CTRL_CLR, HW_PINCTRL_CTRL_SFTRST);
    479 
    480         loop = 0;
    481         while ((PINCTRL_RD(sc, HW_PINCTRL_CTRL) & HW_PINCTRL_CTRL_SFTRST) ||
    482             (loop < PINCTRL_SOFT_RST_LOOP))
    483                 loop++;
    484 
    485         PINCTRL_WR(sc, HW_PINCTRL_CTRL_CLR, HW_PINCTRL_CTRL_CLKGATE);
    486 
    487         /* Wait until clock is in the NON-gated state. */
    488         while (PINCTRL_RD(sc, HW_PINCTRL_CTRL) & HW_PINCTRL_CTRL_CLKGATE);
    489 
    490         return;
    491 }
    492 #endif
    493 
    494 /*
    495  * Enable external USB transceiver/HUB.
    496  *
    497  * PIN18/LCD_D17/USB_EN controls reset line of external USB chip on MINI and
    498  * MAXI boards. We configure this pin to logic 1.
    499  */
    500 void
    501 imx23_pinctrl_en_usb(void)
    502 {
    503 	struct imx23_pinctrl_softc *sc = _sc;
    504 
    505         if (sc == NULL) {
    506                 aprint_error("imx23_pinctrl is not initialized");
    507                 return;
    508         }
    509 
    510 	imx23_pinctrl_gp_pin_ctl(sc, 17, GPIO_PIN_OUTPUT);
    511 	delay(1000);
    512 	imx23_pinctrl_gp_pin_write(sc, 17, 1);
    513 
    514 	return;
    515 }
    516 
    517 static	int
    518 imx23_pinctrl_gp_gc_open(void *cookie, device_t dev)
    519 {
    520 	return 0;
    521 }
    522 
    523 static	void
    524 imx23_pinctrl_gp_gc_close(void *cookie, device_t dev)
    525 {
    526 	return;
    527 }
    528 
    529 static	int
    530 imx23_pinctrl_gp_pin_read(void *cookie, int pin)
    531 {
    532 	int value;
    533 	imx23_pinctrl_softc_t sc = (imx23_pinctrl_softc_t) cookie;
    534 
    535 	if (PINCTRL_RD(sc, PIN2DIN_REG(pin)) & PIN2DIN_MASK(pin))
    536 		value = 1;
    537 	else
    538 		value = 0;
    539 
    540 	return value;
    541 }
    542 
    543 static	void
    544 imx23_pinctrl_gp_pin_write(void *cookie, int pin, int value)
    545 {
    546 	imx23_pinctrl_softc_t sc = (imx23_pinctrl_softc_t) cookie;
    547 
    548 	if (value)
    549 		PINCTRL_WR(sc, PIN2DOUT_SET_REG(pin), PIN2DOUT_MASK(pin));
    550 	else
    551 		PINCTRL_WR(sc, PIN2DOUT_CLR_REG(pin), PIN2DOUT_MASK(pin));
    552 
    553 	return;
    554 }
    555 
    556 /*
    557  * Configure pin as requested in flags.
    558  */
    559 static	void
    560 imx23_pinctrl_gp_pin_ctl(void *cookie, int pin, int flags)
    561 {
    562 	imx23_pinctrl_softc_t sc = (imx23_pinctrl_softc_t) cookie;
    563 	uint32_t tmpr;
    564 
    565 	/* Enable GPIO pin. */
    566 	tmpr = PINCTRL_RD(sc, PIN2MUXSEL_REG(pin));
    567 	tmpr &= ~PIN2MUXSEL_MASK(pin);
    568 	tmpr |= __SHIFTIN(MUXEL_GPIO_MODE, PIN2MUXSEL_MASK(pin));
    569 	PINCTRL_WR(sc, PIN2MUXSEL_REG(pin), tmpr);
    570 
    571 	/* Configure pin drive strength. */
    572 	tmpr = PINCTRL_RD(sc, PIN2DRIVE_REG(pin));
    573 	tmpr &= ~PIN2DRIVE_MASK(pin);
    574 	tmpr |= __SHIFTIN(DRIVE_STRENGTH_4MA, PIN2DRIVE_MASK(pin));
    575 	PINCTRL_WR(sc, PIN2DRIVE_REG(pin), tmpr);
    576 
    577 	if ((flags & (GPIO_PIN_OUTPUT | GPIO_PIN_INOUT))) {
    578 		/* Configure pullup resistor or gate keeper. */
    579 		if (flags & GPIO_PIN_PULLUP)
    580 			PINCTRL_WR(sc, PIN2PULL_SET_REG(pin),
    581 				PIN2PULL_MASK(pin));
    582 		else
    583 			PINCTRL_WR(sc, PIN2PULL_CLR_REG(pin),
    584 				PIN2PULL_MASK(pin));
    585 
    586 		/* Set initial pin value to logic zero. */
    587 		PINCTRL_WR(sc, PIN2DOUT_CLR_REG(pin), PIN2DOUT_MASK(pin));
    588 
    589 		/* Enable pin output. */
    590 		PINCTRL_WR(sc, PIN2DOE_SET_REG(pin), PIN2DOE_MASK(pin));
    591 	}
    592 
    593 	if (flags & GPIO_PIN_INPUT) {
    594 		/* Disable pin output. */
    595 		PINCTRL_WR(sc, PIN2DOE_CLR_REG(pin), PIN2DOE_MASK(pin));
    596 
    597 		/* Configure pullup resistor or gate keeper. */
    598 		if (flags & GPIO_PIN_PULLUP)
    599 			PINCTRL_WR(sc, PIN2PULL_SET_REG(pin),
    600 				PIN2PULL_MASK(pin));
    601 		else
    602 			PINCTRL_WR(sc, PIN2PULL_CLR_REG(pin),
    603 				PIN2PULL_MASK(pin));
    604 	}
    605 
    606 	return;
    607 }
    608