xref: /netbsd-src/sys/dev/i2c/pcagpio.c (revision 3aa5a3ae30f092daa39cb540c574af3082fdc595)
1 /* $NetBSD: pcagpio.c,v 1.12 2022/02/12 03:24:35 riastradh 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 1.12 2022/02/12 03:24:35 riastradh Exp $");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/device.h>
39 #ifdef PCAGPIO_DEBUG
40 #include <sys/kernel.h>
41 #endif
42 #include <sys/conf.h>
43 #include <sys/bus.h>
44 
45 #include <dev/i2c/i2cvar.h>
46 #include <dev/led.h>
47 
48 #ifdef PCAGPIO_DEBUG
49 #define DPRINTF printf
50 #else
51 #define DPRINTF if (0) printf
52 #endif
53 
54 /* commands */
55 #define PCAGPIO_INPUT	0x00	/* line status */
56 #define PCAGPIO_OUTPUT	0x01	/* output status */
57 #define PCAGPIO_REVERT	0x02	/* revert input if set */
58 #define PCAGPIO_CONFIG	0x03	/* input if set, output if not */
59 
60 static int	pcagpio_match(device_t, cfdata_t, void *);
61 static void	pcagpio_attach(device_t, device_t, void *);
62 static int	pcagpio_detach(device_t, int);
63 #ifdef PCAGPIO_DEBUG
64 static void	pcagpio_timeout(void *);
65 #endif
66 
67 /* we can only pass one cookie to led_attach() but we need several values... */
68 struct pcagpio_led {
69 	void *cookie;
70 	struct led_device *led;
71 	uint32_t mask, v_on, v_off;
72 };
73 
74 struct pcagpio_softc {
75 	device_t	sc_dev;
76 	i2c_tag_t	sc_i2c;
77 	i2c_addr_t	sc_addr;
78 
79 	int		sc_is_16bit;
80 	uint32_t	sc_state;
81 	struct pcagpio_led sc_leds[16];
82 	int		sc_nleds;
83 
84 #ifdef PCAGPIO_DEBUG
85 	uint32_t	sc_dir, sc_in;
86 	callout_t	sc_timer;
87 #endif
88 };
89 
90 
91 static void 	pcagpio_writereg(struct pcagpio_softc *, int, uint32_t);
92 static uint32_t pcagpio_readreg(struct pcagpio_softc *, int);
93 static void	pcagpio_attach_led(
94 			struct pcagpio_softc *, char *, int, int, int);
95 static int	pcagpio_get(void *);
96 static void	pcagpio_set(void *, int);
97 
98 CFATTACH_DECL_NEW(pcagpio, sizeof(struct pcagpio_softc),
99     pcagpio_match, pcagpio_attach, pcagpio_detach, NULL);
100 
101 static const struct device_compatible_entry compat_data[] = {
102 	{ .compat = "i2c-pca9555",	.value = 1 },
103 	{ .compat = "pca9555",		.value = 1 },
104 	{ .compat = "i2c-pca9556",	.value = 0 },
105 	{ .compat = "pca9556",		.value = 0 },
106 	DEVICE_COMPAT_EOL
107 };
108 
109 static int
pcagpio_match(device_t parent,cfdata_t match,void * aux)110 pcagpio_match(device_t parent, cfdata_t match, void *aux)
111 {
112 	struct i2c_attach_args *ia = aux;
113 	int match_result;
114 
115 	if (iic_use_direct_match(ia, match, compat_data, &match_result))
116 		return match_result;
117 
118 	return 0;
119 }
120 
121 #ifdef PCAGPIO_DEBUG
122 static void
printdir(char * name,uint32_t val,uint32_t mask,char letter)123 printdir(char* name, uint32_t val, uint32_t mask, char letter)
124 {
125 	char flags[17], bits[17];
126 	uint32_t bit = 0x8000;
127 	int i;
128 
129 	val &= mask;
130 	for (i = 0; i < 16; i++) {
131 		flags[i] = (mask & bit) ? letter : '-';
132 		bits[i] = (val & bit) ? 'X' : ' ';
133 		bit = bit >> 1;
134 	}
135 	flags[16] = 0;
136 	bits[16] = 0;
137 	printf("%s: dir: %s\n", name, flags);
138 	printf("%s: lvl: %s\n", name, bits);
139 }
140 #endif
141 
142 static void
pcagpio_attach(device_t parent,device_t self,void * aux)143 pcagpio_attach(device_t parent, device_t self, void *aux)
144 {
145 	struct pcagpio_softc *sc = device_private(self);
146 	struct i2c_attach_args *ia = aux;
147 	const struct device_compatible_entry *dce;
148 	prop_dictionary_t dict = device_properties(self);
149 	prop_array_t pins;
150 	prop_dictionary_t pin;
151 
152 	sc->sc_dev = self;
153 	sc->sc_i2c = ia->ia_tag;
154 	sc->sc_addr = ia->ia_addr;
155 	sc->sc_nleds = 0;
156 
157 	aprint_naive("\n");
158 	sc->sc_is_16bit = 0;
159 	if ((dce = iic_compatible_lookup(ia, compat_data)) != NULL)
160 		sc->sc_is_16bit = dce->value;
161 
162 	aprint_normal(": %s\n", sc->sc_is_16bit ? "PCA9555" : "PCA9556");
163 
164 	sc->sc_state = pcagpio_readreg(sc, PCAGPIO_OUTPUT);
165 
166 #ifdef PCAGPIO_DEBUG
167 	uint32_t in, out;
168 	sc->sc_dir = pcagpio_readreg(sc, PCAGPIO_CONFIG);
169 	sc->sc_in = pcagpio_readreg(sc, PCAGPIO_INPUT);
170 	in = sc-> sc_in;
171 	out = sc->sc_state;
172 
173 	out &= ~sc->sc_dir;
174 	in &= sc->sc_dir;
175 
176 	printdir(device_xname(sc->sc_dev), in, sc->sc_dir, 'I');
177 	printdir(device_xname(sc->sc_dev), out, ~sc->sc_dir, 'O');
178 
179 	callout_init(&sc->sc_timer, CALLOUT_MPSAFE);
180 	callout_reset(&sc->sc_timer, hz*20, pcagpio_timeout, sc);
181 
182 #endif
183 
184 	pins = prop_dictionary_get(dict, "pins");
185 	if (pins != NULL) {
186 		int i, num, def;
187 		char name[32];
188 		const char *spptr, *nptr;
189 		bool ok = TRUE, act;
190 
191 		for (i = 0; i < prop_array_count(pins); i++) {
192 			nptr = NULL;
193 			pin = prop_array_get(pins, i);
194 			ok &= prop_dictionary_get_string(pin, "name",
195 			    &nptr);
196 			ok &= prop_dictionary_get_uint32(pin, "pin", &num);
197 			ok &= prop_dictionary_get_bool( pin, "active_high",
198 			    &act);
199 			/* optional default state */
200 			def = -1;
201 			prop_dictionary_get_int32(pin, "default_state", &def);
202 			if (!ok)
203 				continue;
204 			/* Extract pin type from the name */
205 			spptr = strstr(nptr, " ");
206 			if (spptr == NULL)
207 				continue;
208 			spptr += 1;
209 			strncpy(name, spptr, 31);
210 			if (!strncmp(nptr, "LED ", 4))
211 				pcagpio_attach_led(sc, name, num, act, def);
212 		}
213 	}
214 }
215 
216 static int
pcagpio_detach(device_t self,int flags)217 pcagpio_detach(device_t self, int flags)
218 {
219 	struct pcagpio_softc *sc = device_private(self);
220 	int i;
221 
222 	for (i = 0; i < sc->sc_nleds; i++)
223 		led_detach(sc->sc_leds[i].led);
224 
225 #ifdef PCAGPIO_DEBUG
226 	callout_halt(&sc->sc_timer, NULL);
227 	callout_destroy(&sc->sc_timer);
228 #endif
229 
230 	return 0;
231 }
232 
233 #ifdef PCAGPIO_DEBUG
234 static void
pcagpio_timeout(void * v)235 pcagpio_timeout(void *v)
236 {
237 	struct pcagpio_softc *sc = v;
238 	uint32_t out, dir, in, o_out, o_in;
239 
240 	out = pcagpio_readreg(sc, PCAGPIO_OUTPUT);
241 	dir = pcagpio_readreg(sc, PCAGPIO_CONFIG);
242 	in = pcagpio_readreg(sc, PCAGPIO_INPUT);
243 	if (out != sc->sc_state || dir != sc->sc_dir || in != sc->sc_in) {
244 		aprint_normal_dev(sc->sc_dev, "status change\n");
245 		o_out = sc->sc_state;
246 		o_in = sc->sc_in;
247 		o_out &= ~sc->sc_dir;
248 		o_in &= sc->sc_dir;
249 		printdir(device_xname(sc->sc_dev), o_in, sc->sc_dir, 'I');
250 		printdir(device_xname(sc->sc_dev), o_out, ~sc->sc_dir, 'O');
251 		sc->sc_state = out;
252 		sc->sc_dir = dir;
253 		sc->sc_in = in;
254 		out &= ~sc->sc_dir;
255 		in &= sc->sc_dir;
256 		printdir(device_xname(sc->sc_dev), in, sc->sc_dir, 'I');
257 		printdir(device_xname(sc->sc_dev), out, ~sc->sc_dir, 'O');
258 	}
259 	callout_reset(&sc->sc_timer, hz*60, pcagpio_timeout, sc);
260 }
261 #endif
262 
263 static void
pcagpio_writereg(struct pcagpio_softc * sc,int reg,uint32_t val)264 pcagpio_writereg(struct pcagpio_softc *sc, int reg, uint32_t val)
265 {
266 	uint8_t cmd;
267 
268 	iic_acquire_bus(sc->sc_i2c, 0);
269 	if (sc->sc_is_16bit) {
270 		uint16_t creg;
271 		cmd = reg << 1;
272 		creg = htole16(val);
273 		iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
274 		    sc->sc_addr, &cmd, 1, &creg, 2, 0);
275 	} else {
276 		uint8_t creg;
277 		cmd = reg;
278 		creg = (uint8_t)val;
279 		iic_exec(sc->sc_i2c, I2C_OP_WRITE_WITH_STOP,
280 		    sc->sc_addr, &cmd, 1, &creg, 1, 0);
281 	}
282 	if (reg == PCAGPIO_OUTPUT) sc->sc_state = val;
283 	iic_release_bus(sc->sc_i2c, 0);
284 }
285 
pcagpio_readreg(struct pcagpio_softc * sc,int reg)286 static uint32_t pcagpio_readreg(struct pcagpio_softc *sc, int reg)
287 {
288 	uint8_t cmd;
289 	uint32_t ret;
290 
291 	iic_acquire_bus(sc->sc_i2c, 0);
292 	if (sc->sc_is_16bit) {
293 		uint16_t creg;
294 		cmd = reg << 1;
295 		iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
296 		    sc->sc_addr, &cmd, 1, &creg, 2, 0);
297 		ret = le16toh(creg);
298 	} else {
299 		uint8_t creg;
300 		cmd = reg;
301 		iic_exec(sc->sc_i2c, I2C_OP_READ_WITH_STOP,
302 		    sc->sc_addr, &cmd, 1, &creg, 1, 0);
303 		ret = creg;
304 	}
305 	iic_release_bus(sc->sc_i2c, 0);
306 	return ret;
307 }
308 
309 static void
pcagpio_attach_led(struct pcagpio_softc * sc,char * n,int pin,int act,int def)310 pcagpio_attach_led(struct pcagpio_softc *sc, char *n, int pin, int act, int def)
311 {
312 	struct pcagpio_led *l;
313 
314 	l = &sc->sc_leds[sc->sc_nleds];
315 	l->cookie = sc;
316 	l->mask = 1 << pin;
317 	l->v_on = act ? l->mask : 0;
318 	l->v_off = act ? 0 : l->mask;
319 	l->led = led_attach(n, l, pcagpio_get, pcagpio_set);
320 	if (def != -1) pcagpio_set(l, def);
321 	DPRINTF("%s: %04x %04x %04x def %d\n",
322 	    __func__, l->mask, l->v_on, l->v_off, def);
323 	sc->sc_nleds++;
324 }
325 
326 static int
pcagpio_get(void * cookie)327 pcagpio_get(void *cookie)
328 {
329 	struct pcagpio_led *l = cookie;
330 	struct pcagpio_softc *sc = l->cookie;
331 
332 	return ((sc->sc_state & l->mask) == l->v_on);
333 }
334 
335 static void
pcagpio_set(void * cookie,int val)336 pcagpio_set(void *cookie, int val)
337 {
338 	struct pcagpio_led *l = cookie;
339 	struct pcagpio_softc *sc = l->cookie;
340 	uint32_t newstate;
341 
342 	newstate = sc->sc_state & ~l->mask;
343 	newstate |= val ? l->v_on : l->v_off;
344 	DPRINTF("%s: %04x -> %04x, %04x %04x %04x\n", __func__,
345 	    sc->sc_state, newstate, l->mask, l->v_on, l->v_off);
346 	if (newstate != sc->sc_state)
347 		pcagpio_writereg(sc, PCAGPIO_OUTPUT, newstate);
348 }
349