xref: /openbsd/sys/dev/i2c/isl1208.c (revision 23c413af)
1 /*	$OpenBSD: isl1208.c,v 1.5 2022/10/15 18:22:53 kettenis Exp $	*/
2 /*
3  * Copyright (c) 2018 Mark Kettenis <kettenis@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/param.h>
19 #include <sys/systm.h>
20 #include <sys/device.h>
21 
22 #include <dev/i2c/i2cvar.h>
23 
24 #include <dev/clock_subr.h>
25 
26 #define ISL1208_SC		0x00
27 #define ISL1208_MN		0x01
28 #define ISL1208_HR		0x02
29 #define  ISL1208_HR_HR21	(1 << 5)
30 #define  ISL1208_HR_MIL		(1 << 7)
31 #define ISL1208_DT		0x03
32 #define ISL1208_MO		0x04
33 #define ISL1208_YR		0x05
34 #define ISL1208_DW		0x06
35 #define ISL1208_SR		0x07
36 #define  ISL1208_SR_RTCF	(1 << 0)
37 #define  ISL1208_SR_WRTC	(1 << 4)
38 
39 #define ISL1208_NRTC_REGS	7
40 
41 struct islrtc_softc {
42 	struct device sc_dev;
43 	i2c_tag_t sc_tag;
44 	i2c_addr_t sc_addr;
45 
46 	struct todr_chip_handle sc_todr;
47 };
48 
49 int	islrtc_match(struct device *, void *, void *);
50 void	islrtc_attach(struct device *, struct device *, void *);
51 
52 const struct cfattach islrtc_ca = {
53 	sizeof(struct islrtc_softc), islrtc_match, islrtc_attach
54 };
55 
56 struct cfdriver islrtc_cd = {
57 	NULL, "islrtc", DV_DULL
58 };
59 
60 uint8_t	islrtc_reg_read(struct islrtc_softc *, int);
61 void	islrtc_reg_write(struct islrtc_softc *, int, uint8_t);
62 int	islrtc_clock_read(struct islrtc_softc *, struct clock_ymdhms *);
63 int	islrtc_clock_write(struct islrtc_softc *, struct clock_ymdhms *);
64 int	islrtc_gettime(struct todr_chip_handle *, struct timeval *);
65 int	islrtc_settime(struct todr_chip_handle *, struct timeval *);
66 
67 int
islrtc_match(struct device * parent,void * match,void * aux)68 islrtc_match(struct device *parent, void *match, void *aux)
69 {
70 	struct i2c_attach_args *ia = aux;
71 
72 	if (strcmp(ia->ia_name, "isil,isl1208") == 0 ||
73 	    strcmp(ia->ia_name, "isil,isl1218") == 0)
74 		return 1;
75 
76 	return 0;
77 }
78 
79 void
islrtc_attach(struct device * parent,struct device * self,void * aux)80 islrtc_attach(struct device *parent, struct device *self, void *aux)
81 {
82 	struct islrtc_softc *sc = (struct islrtc_softc *)self;
83 	struct i2c_attach_args *ia = aux;
84 
85 	sc->sc_tag = ia->ia_tag;
86 	sc->sc_addr = ia->ia_addr;
87 
88 	sc->sc_todr.cookie = sc;
89 	sc->sc_todr.todr_gettime = islrtc_gettime;
90 	sc->sc_todr.todr_settime = islrtc_settime;
91 	sc->sc_todr.todr_quality = 1000;
92 	todr_attach(&sc->sc_todr);
93 
94 	printf("\n");
95 }
96 
97 int
islrtc_gettime(struct todr_chip_handle * handle,struct timeval * tv)98 islrtc_gettime(struct todr_chip_handle *handle, struct timeval *tv)
99 {
100 	struct islrtc_softc *sc = handle->cookie;
101 	struct clock_ymdhms dt;
102 	int error;
103 
104 	error = islrtc_clock_read(sc, &dt);
105 	if (error)
106 		return error;
107 
108 	if (dt.dt_sec > 59 || dt.dt_min > 59 || dt.dt_hour > 23 ||
109 	    dt.dt_day > 31 || dt.dt_day == 0 ||
110 	    dt.dt_mon > 12 || dt.dt_mon == 0 ||
111 	    dt.dt_year < POSIX_BASE_YEAR)
112 		return EINVAL;
113 
114 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
115 	tv->tv_usec = 0;
116 	return 0;
117 }
118 
119 int
islrtc_settime(struct todr_chip_handle * handle,struct timeval * tv)120 islrtc_settime(struct todr_chip_handle *handle, struct timeval *tv)
121 {
122 	struct islrtc_softc *sc = handle->cookie;
123 	struct clock_ymdhms dt;
124 
125 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
126 
127 	return islrtc_clock_write(sc, &dt);
128 }
129 
130 uint8_t
islrtc_reg_read(struct islrtc_softc * sc,int reg)131 islrtc_reg_read(struct islrtc_softc *sc, int reg)
132 {
133 	uint8_t cmd = reg;
134 	uint8_t val;
135 	int error;
136 
137 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
138 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
139 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL);
140 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
141 
142 	if (error) {
143 		printf("%s: can't read register 0x%02x\n",
144 		    sc->sc_dev.dv_xname, reg);
145 		val = 0xff;
146 	}
147 
148 	return val;
149 }
150 
151 void
islrtc_reg_write(struct islrtc_softc * sc,int reg,uint8_t val)152 islrtc_reg_write(struct islrtc_softc *sc, int reg, uint8_t val)
153 {
154 	uint8_t cmd = reg;
155 	int error;
156 
157 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
158 	error = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
159 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL);
160 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
161 
162 	if (error) {
163 		printf("%s: can't write register 0x%02x\n",
164 		    sc->sc_dev.dv_xname, reg);
165 	}
166 }
167 
168 int
islrtc_clock_read(struct islrtc_softc * sc,struct clock_ymdhms * dt)169 islrtc_clock_read(struct islrtc_softc *sc, struct clock_ymdhms *dt)
170 {
171 	uint8_t regs[ISL1208_NRTC_REGS];
172 	uint8_t cmd = ISL1208_SC;
173 	uint8_t status;
174 	int error;
175 
176 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
177 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
178 	    &cmd, sizeof(cmd), regs, ISL1208_NRTC_REGS, I2C_F_POLL);
179 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
180 
181 	if (error) {
182 		printf("%s: can't read RTC\n", sc->sc_dev.dv_xname);
183 		return error;
184 	}
185 
186 	/*
187 	 * Convert the ISL1208's register values into something useable.
188 	 */
189 	dt->dt_sec = FROMBCD(regs[0]);
190 	dt->dt_min = FROMBCD(regs[1]);
191 	if (regs[2] & ISL1208_HR_MIL) {
192 		dt->dt_hour = FROMBCD(regs[2] & ~ISL1208_HR_MIL);
193 	} else {
194 		dt->dt_hour = FROMBCD(regs[2] & ~ISL1208_HR_HR21);
195 		if (regs[2] & ISL1208_HR_HR21)
196 			dt->dt_hour += 12;
197 	}
198 	dt->dt_day = FROMBCD(regs[3]);
199 	dt->dt_mon = FROMBCD(regs[4]);
200 	dt->dt_year = FROMBCD(regs[5]) + 2000;
201 
202 	/* Consider the time to be invalid if we lost power. */
203 	status = islrtc_reg_read(sc, ISL1208_SR);
204 	if (status & ISL1208_SR_RTCF)
205 		return EINVAL;
206 
207 	return 0;
208 }
209 
210 int
islrtc_clock_write(struct islrtc_softc * sc,struct clock_ymdhms * dt)211 islrtc_clock_write(struct islrtc_softc *sc, struct clock_ymdhms *dt)
212 {
213 	uint8_t regs[ISL1208_NRTC_REGS];
214 	uint8_t cmd = ISL1208_SC;
215 	uint8_t reg;
216 	int error;
217 
218 	/*
219 	 * Convert our time representation into something the ISL1208
220 	 * can understand.
221 	 */
222 	regs[0] = TOBCD(dt->dt_sec);
223 	regs[1] = TOBCD(dt->dt_min);
224 	regs[2] = TOBCD(dt->dt_hour) | ISL1208_HR_MIL;
225 	regs[3] = TOBCD(dt->dt_day);
226 	regs[4] = TOBCD(dt->dt_mon);
227 	regs[5] = TOBCD(dt->dt_year - 2000);
228 	regs[6] = TOBCD(dt->dt_wday);
229 
230 	/* Stop RTC such that we can write to it. */
231 	reg = islrtc_reg_read(sc, ISL1208_SR);
232 	if (reg == 0xff) {
233 		error = EIO;
234 		goto fail;
235 	}
236 	islrtc_reg_write(sc, ISL1208_SR, reg | ISL1208_SR_WRTC);
237 
238 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
239 	error = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
240 	    &cmd, sizeof(cmd), regs, ISL1208_NRTC_REGS, I2C_F_POLL);
241 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
242 
243 	/* Restart RTC. */
244 	islrtc_reg_write(sc, ISL1208_SR, reg & ~ISL1208_SR_WRTC);
245 
246 fail:
247 	if (error) {
248 		printf("%s: can't write RTC\n", sc->sc_dev.dv_xname);
249 		return error;
250 	}
251 
252 	return 0;
253 }
254