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x1226.c revision 1.13
      1 /*	$NetBSD: x1226.c,v 1.13 2008/06/08 03:49:26 tsutsui Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2003 Shigeyuki Fukushima.
      5  * All rights reserved.
      6  *
      7  * Written by Shigeyuki Fukushima for the NetBSD Project.
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  * 3. All advertising materials mentioning features or use of this software
     18  *    must display the following acknowledgement:
     19  *      This product includes software developed for the NetBSD Project by
     20  *      Shigeyuki Fukushima.
     21  * 4. The name of Shigeyuki Fukushima may not be used to endorse
     22  *    or promote products derived from this software without specific prior
     23  *    written permission.
     24  *
     25  * THIS SOFTWARE IS PROVIDED BY SHIGEYUKI FUKUSHIMA ``AS IS'' AND
     26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     27  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     28  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL SHIGEYUKI FUKUSHIMA
     29  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     35  * POSSIBILITY OF SUCH DAMAGE.
     36  */
     37 
     38 #include <sys/cdefs.h>
     39 __KERNEL_RCSID(0, "$NetBSD: x1226.c,v 1.13 2008/06/08 03:49:26 tsutsui Exp $");
     40 
     41 #include <sys/param.h>
     42 #include <sys/systm.h>
     43 #include <sys/device.h>
     44 #include <sys/kernel.h>
     45 #include <sys/fcntl.h>
     46 #include <sys/uio.h>
     47 #include <sys/conf.h>
     48 #include <sys/event.h>
     49 
     50 #include <dev/clock_subr.h>
     51 
     52 #include <dev/i2c/i2cvar.h>
     53 #include <dev/i2c/x1226reg.h>
     54 
     55 struct xrtc_softc {
     56 	device_t		sc_dev;
     57 	i2c_tag_t		sc_tag;
     58 	int			sc_address;
     59 	int			sc_open;
     60 	struct todr_chip_handle	sc_todr;
     61 };
     62 
     63 static void	xrtc_attach(device_t, device_t, void *);
     64 static int	xrtc_match(device_t, cfdata_t, void *);
     65 
     66 CFATTACH_DECL_NEW(xrtc, sizeof(struct xrtc_softc),
     67     xrtc_match, xrtc_attach, NULL, NULL);
     68 extern struct cfdriver xrtc_cd;
     69 
     70 dev_type_open(xrtc_open);
     71 dev_type_close(xrtc_close);
     72 dev_type_read(xrtc_read);
     73 dev_type_write(xrtc_write);
     74 
     75 const struct cdevsw xrtc_cdevsw = {
     76 	xrtc_open, xrtc_close, xrtc_read, xrtc_write,
     77 	noioctl, nostop, notty, nopoll, nommap, nokqfilter, D_OTHER
     78 };
     79 
     80 static int xrtc_clock_read(struct xrtc_softc *, struct clock_ymdhms *);
     81 static int xrtc_clock_write(struct xrtc_softc *, struct clock_ymdhms *);
     82 static int xrtc_gettime(struct todr_chip_handle *, volatile struct timeval *);
     83 static int xrtc_settime(struct todr_chip_handle *, volatile struct timeval *);
     84 
     85 /*
     86  * xrtc_match()
     87  */
     88 static int
     89 xrtc_match(device_t parent, cfdata_t cf, void *arg)
     90 {
     91 	struct i2c_attach_args *ia = arg;
     92 
     93 	/* match only this RTC devices */
     94 	if (ia->ia_addr == X1226_ADDR)
     95 		return (1);
     96 
     97 	return (0);
     98 }
     99 
    100 /*
    101  * xrtc_attach()
    102  */
    103 static void
    104 xrtc_attach(device_t parent, device_t self, void *arg)
    105 {
    106 	struct xrtc_softc *sc = device_private(self);
    107 	struct i2c_attach_args *ia = arg;
    108 
    109 	aprint_naive(": Real-time Clock/NVRAM\n");
    110 	aprint_normal(": Xicor X1226 Real-time Clock/NVRAM\n");
    111 
    112 	sc->sc_tag = ia->ia_tag;
    113 	sc->sc_address = ia->ia_addr;
    114 	sc->sc_dev = self;
    115 	sc->sc_open = 0;
    116 	sc->sc_todr.cookie = sc;
    117 	sc->sc_todr.todr_gettime = xrtc_gettime;
    118 	sc->sc_todr.todr_settime = xrtc_settime;
    119 	sc->sc_todr.todr_setwen = NULL;
    120 
    121 	todr_attach(&sc->sc_todr);
    122 }
    123 
    124 
    125 /*ARGSUSED*/
    126 int
    127 xrtc_open(dev_t dev, int flag, int fmt, struct lwp *l)
    128 {
    129 	struct xrtc_softc *sc;
    130 
    131 	if ((sc = device_lookup_private(&xrtc_cd, minor(dev))) == NULL)
    132 		return (ENXIO);
    133 
    134 	/* XXX: Locking */
    135 
    136 	if (sc->sc_open)
    137 		return (EBUSY);
    138 
    139 	sc->sc_open = 1;
    140 	return (0);
    141 }
    142 
    143 /*ARGSUSED*/
    144 int
    145 xrtc_close(dev_t dev, int flag, int fmt, struct lwp *l)
    146 {
    147 	struct xrtc_softc *sc;
    148 
    149 	if ((sc = device_lookup_private(&xrtc_cd, minor(dev))) == NULL)
    150 		return (ENXIO);
    151 
    152 	sc->sc_open = 0;
    153 	return (0);
    154 }
    155 
    156 /*ARGSUSED*/
    157 int
    158 xrtc_read(dev_t dev, struct uio *uio, int flags)
    159 {
    160 	struct xrtc_softc *sc;
    161 	u_int8_t ch, cmdbuf[2];
    162 	int addr, error;
    163 
    164 	if ((sc = device_lookup_private(&xrtc_cd, minor(dev))) == NULL)
    165 		return (ENXIO);
    166 
    167 	if (uio->uio_offset >= X1226_NVRAM_SIZE)
    168 		return (EINVAL);
    169 
    170 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0)
    171 		return (error);
    172 
    173 	while (uio->uio_resid && uio->uio_offset < X1226_NVRAM_SIZE) {
    174 		addr = (int)uio->uio_offset + X1226_NVRAM_START;
    175 		cmdbuf[0] = (addr >> 8) && 0xff;
    176 		cmdbuf[1] = addr && 0xff;
    177 		if ((error = iic_exec(sc->sc_tag,
    178 			I2C_OP_READ_WITH_STOP,
    179 			sc->sc_address, cmdbuf, 2, &ch, 1, 0)) != 0) {
    180 			iic_release_bus(sc->sc_tag, 0);
    181 			aprint_error_dev(sc->sc_dev,
    182 			    "xrtc_read: read failed at 0x%x\n",
    183 				(int)uio->uio_offset);
    184 			return (error);
    185 		}
    186 		if ((error = uiomove(&ch, 1, uio)) != 0) {
    187 			iic_release_bus(sc->sc_tag, 0);
    188 			return (error);
    189 		}
    190 	}
    191 
    192 	iic_release_bus(sc->sc_tag, 0);
    193 
    194 	return (0);
    195 }
    196 
    197 /*ARGSUSED*/
    198 int
    199 xrtc_write(dev_t dev, struct uio *uio, int flags)
    200 {
    201 	struct xrtc_softc *sc;
    202 	u_int8_t cmdbuf[3];
    203 	int addr, error;
    204 
    205 	if ((sc = device_lookup_private(&xrtc_cd, minor(dev))) == NULL)
    206 		return (ENXIO);
    207 
    208 	if (uio->uio_offset >= X1226_NVRAM_SIZE)
    209 		return (EINVAL);
    210 
    211 	if ((error = iic_acquire_bus(sc->sc_tag, 0)) != 0)
    212 		return (error);
    213 
    214 	while (uio->uio_resid && uio->uio_offset < X1226_NVRAM_SIZE) {
    215 		addr = (int)uio->uio_offset + X1226_NVRAM_START;
    216 		cmdbuf[0] = (addr >> 8) && 0xff;
    217 		cmdbuf[1] = addr && 0xff;
    218 		if ((error = uiomove(&cmdbuf[2], 1, uio)) != 0) {
    219 			break;
    220 		}
    221 		if ((error = iic_exec(sc->sc_tag,
    222 			uio->uio_resid ? I2C_OP_WRITE : I2C_OP_WRITE_WITH_STOP,
    223 			sc->sc_address, cmdbuf, 2, &cmdbuf[2], 1, 0)) != 0) {
    224 			iic_release_bus(sc->sc_tag, 0);
    225 			aprint_error_dev(sc->sc_dev,
    226 			    "xrtc_write: write failed at 0x%x\n",
    227 				(int)uio->uio_offset);
    228 			return (error);
    229 		}
    230 	}
    231 
    232 	iic_release_bus(sc->sc_tag, 0);
    233 
    234 	return (0);
    235 }
    236 
    237 
    238 static int
    239 xrtc_gettime(struct todr_chip_handle *ch, volatile struct timeval *tv)
    240 {
    241 	struct xrtc_softc *sc = ch->cookie;
    242 	struct clock_ymdhms dt, check;
    243 	int retries;
    244 
    245 	memset(&dt, 0, sizeof(dt));
    246 	memset(&check, 0, sizeof(check));
    247 
    248 	retries = 5;
    249 	do {
    250 		xrtc_clock_read(sc, &dt);
    251 		xrtc_clock_read(sc, &check);
    252 	} while (memcmp(&dt, &check, sizeof(check)) != 0 && --retries);
    253 
    254 	tv->tv_sec = clock_ymdhms_to_secs(&dt);
    255 	tv->tv_usec = 0;
    256 
    257 	return (0);
    258 }
    259 
    260 static int
    261 xrtc_settime(struct todr_chip_handle *ch, volatile struct timeval *tv)
    262 {
    263 	struct xrtc_softc *sc = ch->cookie;
    264 	struct clock_ymdhms dt;
    265 
    266 	clock_secs_to_ymdhms(tv->tv_sec, &dt);
    267 
    268 	if (xrtc_clock_write(sc, &dt) == 0)
    269 		return (-1);
    270 
    271 	return (0);
    272 }
    273 
    274 static int
    275 xrtc_clock_read(struct xrtc_softc *sc, struct clock_ymdhms *dt)
    276 {
    277 	int i = 0;
    278 	u_int8_t bcd[X1226_REG_RTC_SIZE], cmdbuf[2];
    279 
    280 	if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL)) {
    281 		aprint_error_dev(sc->sc_dev,
    282 		    "xrtc_clock_read: failed to acquire I2C bus\n");
    283 		return (0);
    284 	}
    285 
    286 	/* Read each RTC register in order */
    287 	for (i = 0 ; i < X1226_REG_RTC_SIZE ; i++) {
    288 		int addr = i + X1226_REG_RTC_BASE;
    289 		cmdbuf[0] = (addr >> 8) & 0xff;
    290 		cmdbuf[1] = addr & 0xff;
    291 
    292 		if (iic_exec(sc->sc_tag,
    293 			I2C_OP_READ_WITH_STOP,
    294 			sc->sc_address, cmdbuf, 2,
    295 			&bcd[i], 1, I2C_F_POLL)) {
    296 			iic_release_bus(sc->sc_tag, I2C_F_POLL);
    297 			aprint_error_dev(sc->sc_dev,
    298 			    "xrtc_clock_read: failed to read rtc "
    299 				"at 0x%x\n", i);
    300 			return (0);
    301 		}
    302 	}
    303 
    304 	/* Done with I2C */
    305 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
    306 
    307 	/*
    308 	 * Convert the X1226's register bcd values
    309 	 */
    310 	dt->dt_sec = FROMBCD(bcd[X1226_REG_SC - X1226_REG_RTC_BASE]
    311 			& X1226_REG_SC_MASK);
    312 	dt->dt_min = FROMBCD(bcd[X1226_REG_MN - X1226_REG_RTC_BASE]
    313 			& X1226_REG_MN_MASK);
    314 	if (!(bcd[X1226_REG_HR - X1226_REG_RTC_BASE] & X1226_FLAG_HR_24H)) {
    315 		dt->dt_hour = FROMBCD(bcd[X1226_REG_HR - X1226_REG_RTC_BASE]
    316 				& X1226_REG_HR12_MASK);
    317 		if (bcd[X1226_REG_HR - X1226_REG_RTC_BASE] & X1226_FLAG_HR_12HPM) {
    318 			dt->dt_hour += 12;
    319 		}
    320 	} else {
    321 		dt->dt_hour = FROMBCD(bcd[X1226_REG_HR - X1226_REG_RTC_BASE]
    322 			& X1226_REG_HR24_MASK);
    323 	}
    324 	dt->dt_wday = FROMBCD(bcd[X1226_REG_DW - X1226_REG_RTC_BASE]
    325 			& X1226_REG_DT_MASK);
    326 	dt->dt_day = FROMBCD(bcd[X1226_REG_DT - X1226_REG_RTC_BASE]
    327 			& X1226_REG_DT_MASK);
    328 	dt->dt_mon = FROMBCD(bcd[X1226_REG_MO - X1226_REG_RTC_BASE]
    329 			& X1226_REG_MO_MASK);
    330 	dt->dt_year = FROMBCD(bcd[X1226_REG_YR - X1226_REG_RTC_BASE]
    331 			& X1226_REG_YR_MASK);
    332 	dt->dt_year += FROMBCD(bcd[X1226_REG_Y2K - X1226_REG_RTC_BASE]
    333 			& X1226_REG_Y2K_MASK) * 100;
    334 
    335 	return (1);
    336 }
    337 
    338 static int
    339 xrtc_clock_write(struct xrtc_softc *sc, struct clock_ymdhms *dt)
    340 {
    341 	int i = 0, addr;
    342 	u_int8_t bcd[X1226_REG_RTC_SIZE], cmdbuf[3];
    343 
    344 	/*
    345 	 * Convert our time to bcd values
    346 	 */
    347 	bcd[X1226_REG_SC - X1226_REG_RTC_BASE] = TOBCD(dt->dt_sec);
    348 	bcd[X1226_REG_MN - X1226_REG_RTC_BASE] = TOBCD(dt->dt_min);
    349 	bcd[X1226_REG_HR - X1226_REG_RTC_BASE] = TOBCD(dt->dt_hour)
    350 						| X1226_FLAG_HR_24H;
    351 	bcd[X1226_REG_DW - X1226_REG_RTC_BASE] = TOBCD(dt->dt_wday);
    352 	bcd[X1226_REG_DT - X1226_REG_RTC_BASE] = TOBCD(dt->dt_day);
    353 	bcd[X1226_REG_MO - X1226_REG_RTC_BASE] = TOBCD(dt->dt_mon);
    354 	bcd[X1226_REG_YR - X1226_REG_RTC_BASE] = TOBCD(dt->dt_year % 100);
    355 	bcd[X1226_REG_Y2K - X1226_REG_RTC_BASE] = TOBCD(dt->dt_year / 100);
    356 
    357 	if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL)) {
    358 		aprint_error_dev(sc->sc_dev,
    359 		    "xrtc_clock_write: failed to acquire I2C bus\n");
    360 		return (0);
    361 	}
    362 
    363 	/* Unlock register: Write Enable Latch */
    364 	addr = X1226_REG_SR;
    365 	cmdbuf[0] = ((addr >> 8) & 0xff);
    366 	cmdbuf[1] = (addr & 0xff);
    367 	cmdbuf[2] = X1226_FLAG_SR_WEL;
    368 	if (iic_exec(sc->sc_tag,
    369 		I2C_OP_WRITE_WITH_STOP,
    370 		sc->sc_address, cmdbuf, 2, &cmdbuf[2], 1, 0) != 0) {
    371 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
    372 		aprint_error_dev(sc->sc_dev, "xrtc_clock_write: "
    373 			"failed to write-unlock status register(WEL=1)\n");
    374 		return (0);
    375 	}
    376 
    377 	/* Unlock register: Register Write Enable Latch */
    378 	addr = X1226_REG_SR;
    379 	cmdbuf[0] = ((addr >> 8) & 0xff);
    380 	cmdbuf[1] = (addr & 0xff);
    381 	cmdbuf[2] = X1226_FLAG_SR_WEL | X1226_FLAG_SR_RWEL;
    382 	if (iic_exec(sc->sc_tag,
    383 		I2C_OP_WRITE_WITH_STOP,
    384 		sc->sc_address, cmdbuf, 2, &cmdbuf[2], 1, 0) != 0) {
    385 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
    386 		aprint_error_dev(sc->sc_dev, "xrtc_clock_write: "
    387 			"failed to write-unlock status register(RWEL=1)\n");
    388 		return (0);
    389 	}
    390 
    391 	/* Write each RTC register in reverse order */
    392 	for (i = (X1226_REG_RTC_SIZE - 1) ; i >= 0; i--) {
    393 		addr = i + X1226_REG_RTC_BASE;
    394 		cmdbuf[0] = ((addr >> 8) & 0xff);
    395 		cmdbuf[1] = (addr & 0xff);
    396 		if (iic_exec(sc->sc_tag,
    397 			I2C_OP_WRITE_WITH_STOP,
    398 			sc->sc_address, cmdbuf, 2,
    399 			&bcd[i], 1, I2C_F_POLL)) {
    400 
    401 			/* Lock register: WEL/RWEL off */
    402 			addr = X1226_REG_SR;
    403 			cmdbuf[0] = ((addr >> 8) & 0xff);
    404 			cmdbuf[1] = (addr & 0xff);
    405 			cmdbuf[2] = 0;
    406 			iic_exec(sc->sc_tag,
    407 				I2C_OP_WRITE_WITH_STOP,
    408 				sc->sc_address, cmdbuf, 2,
    409 				&cmdbuf[2], 1, 0);
    410 
    411 			iic_release_bus(sc->sc_tag, I2C_F_POLL);
    412 			aprint_error_dev(sc->sc_dev, "xrtc_clock_write: failed to write rtc "
    413 				"at 0x%x\n", i);
    414 			return (0);
    415 		}
    416 	}
    417 
    418 	/* Lock register: WEL/RWEL off */
    419 	addr = X1226_REG_SR;
    420 	cmdbuf[0] = ((addr >> 8) & 0xff);
    421 	cmdbuf[1] = (addr & 0xff);
    422 	cmdbuf[2] = 0;
    423 	if (iic_exec(sc->sc_tag,
    424 		I2C_OP_WRITE_WITH_STOP,
    425 		sc->sc_address, cmdbuf, 2, &cmdbuf[2], 1, 0) != 0) {
    426 		iic_release_bus(sc->sc_tag, I2C_F_POLL);
    427 		aprint_error_dev(sc->sc_dev, "xrtc_clock_write: "
    428 			"failed to write-lock status register\n");
    429 		return (0);
    430 	}
    431 
    432 	iic_release_bus(sc->sc_tag, I2C_F_POLL);
    433 	return (1);
    434 }
    435