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      1 /* $NetBSD: pcagpio.c,v 1.13 2025/07/09 08:32:48 macallan Exp $ */
      2 
      3 /*-
      4  * Copyright (c) 2020 Michael Lorenz
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     26  * POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 /*
     30  * a driver for Philips Semiconductor PCA9555 GPIO controllers
     31  */
     32 
     33 #include <sys/cdefs.h>
     34 __KERNEL_RCSID(0, "$NetBSD: pcagpio.c,v 1.13 2025/07/09 08:32:48 macallan Exp $");
     35 
     36 #include <sys/param.h>
     37 #include <sys/systm.h>
     38 #include <sys/device.h>
     39 #include <sys/conf.h>
     40 #include <sys/bus.h>
     41 
     42 #include <dev/i2c/i2cvar.h>
     43 #include <dev/led.h>
     44 
     45 #ifdef PCAGPIO_DEBUG
     46 #define DPRINTF printf
     47 #else
     48 #define DPRINTF if (0) printf
     49 #endif
     50 
     51 /* commands */
     52 #define PCAGPIO_INPUT	0x00	/* line status */
     53 #define PCAGPIO_OUTPUT	0x01	/* output status */
     54 #define PCAGPIO_REVERT	0x02	/* revert input if set */
     55 #define PCAGPIO_CONFIG	0x03	/* input if set, output if not */
     56 
     57 static int	pcagpio_match(device_t, cfdata_t, void *);
     58 static void	pcagpio_attach(device_t, device_t, void *);
     59 static int	pcagpio_detach(device_t, int);
     60 
     61 /* we can only pass one cookie to led_attach() but we need several values... */
     62 struct pcagpio_led {
     63 	void *cookie;
     64 	struct led_device *led;
     65 	uint32_t mask, v_on, v_off;
     66 };
     67 
     68 struct pcagpio_softc {
     69 	device_t	sc_dev;
     70 	i2c_tag_t	sc_i2c;
     71 	i2c_addr_t	sc_addr;
     72 
     73 	int		sc_is_16bit;
     74 	uint32_t	sc_state;
     75 	struct pcagpio_led sc_leds[16];
     76 	int		sc_nleds;
     77 
     78 #ifdef PCAGPIO_DEBUG
     79 	uint32_t	sc_dir, sc_in;
     80 #endif
     81 };
     82 
     83 
     84 static void 	pcagpio_writereg(struct pcagpio_softc *, int, uint32_t);
     85 static uint32_t pcagpio_readreg(struct pcagpio_softc *, int);
     86 static void	pcagpio_attach_led(
     87 			struct pcagpio_softc *, char *, int, int, int);
     88 static int	pcagpio_get(void *);
     89 static void	pcagpio_set(void *, int);
     90 
     91 CFATTACH_DECL_NEW(pcagpio, sizeof(struct pcagpio_softc),
     92     pcagpio_match, pcagpio_attach, pcagpio_detach, NULL);
     93 
     94 static const struct device_compatible_entry compat_data[] = {
     95 	{ .compat = "i2c-pca9555",	.value = 1 },
     96 	{ .compat = "pca9555",		.value = 1 },
     97 	{ .compat = "i2c-pca9556",	.value = 0 },
     98 	{ .compat = "pca9556",		.value = 0 },
     99 	DEVICE_COMPAT_EOL
    100 };
    101 
    102 static int
    103 pcagpio_match(device_t parent, cfdata_t match, void *aux)
    104 {
    105 	struct i2c_attach_args *ia = aux;
    106 	int match_result;
    107 
    108 	if (iic_use_direct_match(ia, match, compat_data, &match_result))
    109 		return match_result;
    110 
    111 	return 0;
    112 }
    113 
    114 #ifdef PCAGPIO_DEBUG
    115 static void
    116 printdir(const char* name, uint32_t val, uint32_t mask, char letter)
    117 {
    118 	char flags[17], bits[17];
    119 	uint32_t bit = 0x8000;
    120 	int i;
    121 
    122 	val &= mask;
    123 	for (i = 0; i < 16; i++) {
    124 		flags[i] = (mask & bit) ? letter : '-';
    125 		bits[i] = (val & bit) ? 'X' : ' ';
    126 		bit = bit >> 1;
    127 	}
    128 	flags[16] = 0;
    129 	bits[16] = 0;
    130 	printf("%s: dir: %s\n", name, flags);
    131 	printf("%s: lvl: %s\n", name, bits);
    132 }
    133 #endif
    134 
    135 static void
    136 pcagpio_attach(device_t parent, device_t self, void *aux)
    137 {
    138 	struct pcagpio_softc *sc = device_private(self);
    139 	struct i2c_attach_args *ia = aux;
    140 	const struct device_compatible_entry *dce;
    141 	prop_dictionary_t dict = device_properties(self);
    142 	prop_array_t pins;
    143 	prop_dictionary_t pin;
    144 
    145 	sc->sc_dev = self;
    146 	sc->sc_i2c = ia->ia_tag;
    147 	sc->sc_addr = ia->ia_addr;
    148 	sc->sc_nleds = 0;
    149 
    150 	aprint_naive("\n");
    151 	sc->sc_is_16bit = 0;
    152 	if ((dce = iic_compatible_lookup(ia, compat_data)) != NULL)
    153 		sc->sc_is_16bit = dce->value;
    154 
    155 	aprint_normal(": %s\n", sc->sc_is_16bit ? "PCA9555" : "PCA9556");
    156 
    157 	sc->sc_state = pcagpio_readreg(sc, PCAGPIO_OUTPUT);
    158 
    159 #ifdef PCAGPIO_DEBUG
    160 	uint32_t in, out;
    161 	sc->sc_dir = pcagpio_readreg(sc, PCAGPIO_CONFIG);
    162 	sc->sc_in = pcagpio_readreg(sc, PCAGPIO_INPUT);
    163 	in = sc-> sc_in;
    164 	out = sc->sc_state;
    165 
    166 	out &= ~sc->sc_dir;
    167 	in &= sc->sc_dir;
    168 
    169 	printdir(device_xname(sc->sc_dev), in, sc->sc_dir, 'I');
    170 	printdir(device_xname(sc->sc_dev), out, ~sc->sc_dir, 'O');
    171 
    172 #endif
    173 
    174 	pins = prop_dictionary_get(dict, "pins");
    175 	if (pins != NULL) {
    176 		int i, num, def;
    177 		char name[32];
    178 		const char *spptr, *nptr;
    179 		bool ok = TRUE, act;
    180 
    181 		for (i = 0; i < prop_array_count(pins); i++) {
    182 			nptr = NULL;
    183 			pin = prop_array_get(pins, i);
    184 			ok &= prop_dictionary_get_string(pin, "name",
    185 			    &nptr);
    186 			ok &= prop_dictionary_get_uint32(pin, "pin", &num);
    187 			ok &= prop_dictionary_get_bool( pin, "active_high",
    188 			    &act);
    189 			/* optional default state */
    190 			def = -1;
    191 			prop_dictionary_get_int32(pin, "default_state", &def);
    192 			if (!ok)
    193 				continue;
    194 			/* Extract pin type from the name */
    195 			spptr = strstr(nptr, " ");
    196 			if (spptr == NULL)
    197 				continue;
    198 			spptr += 1;
    199 			strncpy(name, spptr, 31);
    200 			if (!strncmp(nptr, "LED ", 4))
    201 				pcagpio_attach_led(sc, name, num, act, def);
    202 		}
    203 	}
    204 }
    205 
    206 static int
    207 pcagpio_detach(device_t self, int flags)
    208 {
    209 	struct pcagpio_softc *sc = device_private(self);
    210 	int i;
    211 
    212 	for (i = 0; i < sc->sc_nleds; i++)
    213 		led_detach(sc->sc_leds[i].led);
    214 
    215 	return 0;
    216 }
    217 
    218 static void
    219 pcagpio_writereg(struct pcagpio_softc *sc, int reg, uint32_t val)
    220 {
    221 	uint8_t cmd;
    222 
    223 	iic_acquire_bus(sc->sc_i2c, 0);
    224 	if (sc->sc_is_16bit) {
    225 		uint16_t creg;
    226 		cmd = reg << 1;
    227 		creg = htole16(val);
    228 		iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
    229 		    sc->sc_addr, &cmd, 1, &creg, 2, 0);
    230 	} else {
    231 		uint8_t creg;
    232 		cmd = reg;
    233 		creg = (uint8_t)val;
    234 		iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
    235 		    sc->sc_addr, &cmd, 1, &creg, 1, 0);
    236 	}
    237 	if (reg == PCAGPIO_OUTPUT) sc->sc_state = val;
    238 	iic_release_bus(sc->sc_i2c, 0);
    239 }
    240 
    241 static uint32_t pcagpio_readreg(struct pcagpio_softc *sc, int reg)
    242 {
    243 	uint8_t cmd;
    244 	uint32_t ret;
    245 
    246 	iic_acquire_bus(sc->sc_i2c, 0);
    247 	if (sc->sc_is_16bit) {
    248 		uint16_t creg;
    249 		cmd = reg << 1;
    250 		iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
    251 		    sc->sc_addr, &cmd, 1, &creg, 2, 0);
    252 		ret = le16toh(creg);
    253 	} else {
    254 		uint8_t creg;
    255 		cmd = reg;
    256 		iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
    257 		    sc->sc_addr, &cmd, 1, &creg, 1, 0);
    258 		ret = creg;
    259 	}
    260 	iic_release_bus(sc->sc_i2c, 0);
    261 	return ret;
    262 }
    263 
    264 static void
    265 pcagpio_attach_led(struct pcagpio_softc *sc, char *n, int pin, int act, int def)
    266 {
    267 	struct pcagpio_led *l;
    268 
    269 	l = &sc->sc_leds[sc->sc_nleds];
    270 	l->cookie = sc;
    271 	l->mask = 1 << pin;
    272 	l->v_on = act ? l->mask : 0;
    273 	l->v_off = act ? 0 : l->mask;
    274 	l->led = led_attach(n, l, pcagpio_get, pcagpio_set);
    275 	if (def != -1) pcagpio_set(l, def);
    276 	DPRINTF("%s: %04x %04x %04x def %d\n",
    277 	    __func__, l->mask, l->v_on, l->v_off, def);
    278 	sc->sc_nleds++;
    279 }
    280 
    281 static int
    282 pcagpio_get(void *cookie)
    283 {
    284 	struct pcagpio_led *l = cookie;
    285 	struct pcagpio_softc *sc = l->cookie;
    286 
    287 	return ((sc->sc_state & l->mask) == l->v_on);
    288 }
    289 
    290 static void
    291 pcagpio_set(void *cookie, int val)
    292 {
    293 	struct pcagpio_led *l = cookie;
    294 	struct pcagpio_softc *sc = l->cookie;
    295 	uint32_t newstate;
    296 
    297 	newstate = sc->sc_state & ~l->mask;
    298 	newstate |= val ? l->v_on : l->v_off;
    299 	DPRINTF("%s: %04x -> %04x, %04x %04x %04x\n", __func__,
    300 	    sc->sc_state, newstate, l->mask, l->v_on, l->v_off);
    301 	if (newstate != sc->sc_state)
    302 		pcagpio_writereg(sc, PCAGPIO_OUTPUT, newstate);
    303 }
    304