xref: /openbsd-src/sys/dev/i2c/isl1208.c (revision c90a81c56dcebd6a1b73fe4aff9b03385b8e63b3)
1 /*	$OpenBSD: isl1208.c,v 1.1 2018/04/07 18:16:35 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 #include <sys/malloc.h>
22 
23 #include <dev/i2c/i2cvar.h>
24 
25 #include <dev/clock_subr.h>
26 
27 extern todr_chip_handle_t todr_handle;
28 
29 #define ISL1208_SC		0x00
30 #define ISL1208_MN		0x01
31 #define ISL1208_HR		0x02
32 #define  ISL1208_HR_HR21	(1 << 5)
33 #define  ISL1208_HR_MIL		(1 << 7)
34 #define ISL1208_DT		0x03
35 #define ISL1208_MO		0x04
36 #define ISL1208_YR		0x05
37 #define ISL1208_DW		0x06
38 #define ISL1208_SR		0x07
39 #define  ISL1208_SR_RTCF	(1 << 0)
40 #define  ISL1208_SR_WRTC	(1 << 4)
41 
42 #define ISL1208_NRTC_REGS	7
43 
44 struct islrtc_regdata {
45 	const char *name;
46 	uint8_t reg, mask;
47 	uint32_t base, delta;
48 };
49 
50 struct islrtc_softc {
51 	struct device sc_dev;
52 	i2c_tag_t sc_tag;
53 	i2c_addr_t sc_addr;
54 
55 	struct todr_chip_handle sc_todr;
56 };
57 
58 int	islrtc_match(struct device *, void *, void *);
59 void	islrtc_attach(struct device *, struct device *, void *);
60 
61 struct cfattach islrtc_ca = {
62 	sizeof(struct islrtc_softc), islrtc_match, islrtc_attach
63 };
64 
65 struct cfdriver islrtc_cd = {
66 	NULL, "islrtc", DV_DULL
67 };
68 
69 uint8_t	islrtc_reg_read(struct islrtc_softc *, int);
70 void	islrtc_reg_write(struct islrtc_softc *, int, uint8_t);
71 int	islrtc_clock_read(struct islrtc_softc *, struct clock_ymdhms *);
72 int	islrtc_clock_write(struct islrtc_softc *, struct clock_ymdhms *);
73 int	islrtc_gettime(struct todr_chip_handle *, struct timeval *);
74 int	islrtc_settime(struct todr_chip_handle *, struct timeval *);
75 
76 int
77 islrtc_match(struct device *parent, void *match, void *aux)
78 {
79 	struct i2c_attach_args *ia = aux;
80 
81 	if (strcmp(ia->ia_name, "isil,isl1208") == 0 ||
82 	    strcmp(ia->ia_name, "isil,isl1218") == 0)
83 		return 1;
84 
85 	return 0;
86 }
87 
88 void
89 islrtc_attach(struct device *parent, struct device *self, void *aux)
90 {
91 	struct islrtc_softc *sc = (struct islrtc_softc *)self;
92 	struct i2c_attach_args *ia = aux;
93 
94 	sc->sc_tag = ia->ia_tag;
95 	sc->sc_addr = ia->ia_addr;
96 
97 	sc->sc_todr.cookie = sc;
98 	sc->sc_todr.todr_gettime = islrtc_gettime;
99 	sc->sc_todr.todr_settime = islrtc_settime;
100 	todr_handle = &sc->sc_todr;
101 
102 	printf("\n");
103 }
104 
105 int
106 islrtc_gettime(struct todr_chip_handle *handle, struct timeval *tv)
107 {
108 	struct islrtc_softc *sc = handle->cookie;
109 	struct clock_ymdhms dt;
110 	int error;
111 
112 	error = islrtc_clock_read(sc, &dt);
113 	if (error)
114 		return error;
115 
116 	if (dt.dt_sec > 59 || dt.dt_min > 59 || dt.dt_hour > 23 ||
117 	    dt.dt_day > 31 || dt.dt_day == 0 ||
118 	    dt.dt_mon > 12 || dt.dt_mon == 0 ||
119 	    dt.dt_year < POSIX_BASE_YEAR)
120 		return EINVAL;
121 
122 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
123 	tv->tv_usec = 0;
124 	return 0;
125 }
126 
127 int
128 islrtc_settime(struct todr_chip_handle *handle, struct timeval *tv)
129 {
130 	struct islrtc_softc *sc = handle->cookie;
131 	struct clock_ymdhms dt;
132 
133 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
134 
135 	return islrtc_clock_write(sc, &dt);
136 }
137 
138 uint8_t
139 islrtc_reg_read(struct islrtc_softc *sc, int reg)
140 {
141 	uint8_t cmd = reg;
142 	uint8_t val;
143 	int error;
144 
145 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
146 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
147 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL);
148 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
149 
150 	if (error) {
151 		printf("%s: can't read register 0x%02x\n",
152 		    sc->sc_dev.dv_xname, reg);
153 		val = 0xff;
154 	}
155 
156 	return val;
157 }
158 
159 void
160 islrtc_reg_write(struct islrtc_softc *sc, int reg, uint8_t val)
161 {
162 	uint8_t cmd = reg;
163 	int error;
164 
165 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
166 	error = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
167 	    &cmd, sizeof cmd, &val, sizeof val, I2C_F_POLL);
168 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
169 
170 	if (error) {
171 		printf("%s: can't write register 0x%02x\n",
172 		    sc->sc_dev.dv_xname, reg);
173 	}
174 }
175 
176 int
177 islrtc_clock_read(struct islrtc_softc *sc, struct clock_ymdhms *dt)
178 {
179 	uint8_t regs[ISL1208_NRTC_REGS];
180 	uint8_t cmd = ISL1208_SC;
181 	uint8_t status;
182 	int error;
183 
184 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
185 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr,
186 	    &cmd, sizeof(cmd), regs, ISL1208_NRTC_REGS, I2C_F_POLL);
187 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
188 
189 	if (error) {
190 		printf("%s: can't read RTC\n", sc->sc_dev.dv_xname);
191 		return error;
192 	}
193 
194 	/*
195 	 * Convert the ISL1208's register values into something useable.
196 	 */
197 	dt->dt_sec = FROMBCD(regs[0]);
198 	dt->dt_min = FROMBCD(regs[1]);
199 	if (regs[2] & ISL1208_HR_MIL) {
200 		dt->dt_hour = FROMBCD(regs[2] & ~ISL1208_HR_MIL);
201 	} else {
202 		dt->dt_hour = FROMBCD(regs[2] & ~ISL1208_HR_HR21);
203 		if (regs[2] & ISL1208_HR_HR21)
204 			dt->dt_hour += 12;
205 	}
206 	dt->dt_day = FROMBCD(regs[3]);
207 	dt->dt_mon = FROMBCD(regs[4]);
208 	dt->dt_year = FROMBCD(regs[5]) + 2000;
209 
210 	/* Consider the time to be invalid if we lost power. */
211 	status = islrtc_reg_read(sc, ISL1208_SR);
212 	if (status & ISL1208_SR_RTCF)
213 		return EINVAL;
214 
215 	return 0;
216 }
217 
218 int
219 islrtc_clock_write(struct islrtc_softc *sc, struct clock_ymdhms *dt)
220 {
221 	uint8_t regs[ISL1208_NRTC_REGS];
222 	uint8_t cmd = ISL1208_SC;
223 	uint8_t reg;
224 	int error;
225 
226 	/*
227 	 * Convert our time representation into something the ISL1208
228 	 * can understand.
229 	 */
230 	regs[0] = TOBCD(dt->dt_sec);
231 	regs[1] = TOBCD(dt->dt_min);
232 	regs[2] = TOBCD(dt->dt_hour) | ISL1208_HR_MIL;
233 	regs[3] = TOBCD(dt->dt_day);
234 	regs[4] = TOBCD(dt->dt_mon);
235 	regs[5] = TOBCD(dt->dt_year - 2000);
236 	regs[6] = TOBCD(dt->dt_wday);
237 
238 	/* Stop RTC such that we can write to it. */
239 	reg = islrtc_reg_read(sc, ISL1208_SR);
240 	if (reg == 0xff) {
241 		error = EIO;
242 		goto fail;
243 	}
244 	islrtc_reg_write(sc, ISL1208_SR, reg | ISL1208_SR_WRTC);
245 
246 	iic_acquire_bus(sc->sc_tag, I2C_F_POLL);
247 	error = iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr,
248 	    &cmd, sizeof(cmd), regs, ISL1208_NRTC_REGS, I2C_F_POLL);
249 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
250 
251 	/* Restart RTC. */
252 	islrtc_reg_write(sc, ISL1208_SR, reg & ~ISL1208_SR_WRTC);
253 
254 fail:
255 	if (error) {
256 		printf("%s: can't write RTC\n", sc->sc_dev.dv_xname);
257 		return error;
258 	}
259 
260 	return 0;
261 }
262