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sdtemp.c revision 1.9.2.2
      1 /*      $NetBSD: sdtemp.c,v 1.9.2.2 2010/08/17 06:46:08 uebayasi Exp $        */
      2 
      3 /*
      4  * Copyright (c) 2009 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Paul Goyette.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 __KERNEL_RCSID(0, "$NetBSD: sdtemp.c,v 1.9.2.2 2010/08/17 06:46:08 uebayasi Exp $");
     34 
     35 #include <sys/param.h>
     36 #include <sys/systm.h>
     37 #include <sys/kmem.h>
     38 #include <sys/device.h>
     39 #include <sys/kernel.h>
     40 #include <sys/endian.h>
     41 
     42 #include <dev/sysmon/sysmonvar.h>
     43 
     44 #include <dev/i2c/i2cvar.h>
     45 #include <dev/i2c/sdtemp_reg.h>
     46 
     47 struct sdtemp_softc {
     48 	device_t sc_dev;
     49 	i2c_tag_t sc_tag;
     50 	int sc_address;
     51 
     52 	struct sysmon_envsys *sc_sme;
     53 	envsys_data_t *sc_sensor;
     54 	sysmon_envsys_lim_t sc_deflims;
     55 	uint32_t sc_defprops;
     56 	int sc_resolution;
     57 	uint16_t sc_capability;
     58 };
     59 
     60 static int  sdtemp_match(device_t, cfdata_t, void *);
     61 static void sdtemp_attach(device_t, device_t, void *);
     62 
     63 CFATTACH_DECL_NEW(sdtemp, sizeof(struct sdtemp_softc),
     64 	sdtemp_match, sdtemp_attach, NULL, NULL);
     65 
     66 static void	sdtemp_refresh(struct sysmon_envsys *, envsys_data_t *);
     67 static void	sdtemp_get_limits(struct sysmon_envsys *, envsys_data_t *,
     68 				  sysmon_envsys_lim_t *, uint32_t *);
     69 static void	sdtemp_set_limits(struct sysmon_envsys *, envsys_data_t *,
     70 				  sysmon_envsys_lim_t *, uint32_t *);
     71 #ifdef NOT_YET
     72 static int	sdtemp_read_8(struct sdtemp_softc *, uint8_t, uint8_t *);
     73 static int	sdtemp_write_8(struct sdtemp_softc *, uint8_t, uint8_t);
     74 #endif /* NOT YET */
     75 static int	sdtemp_read_16(struct sdtemp_softc *, uint8_t, uint16_t *);
     76 static int	sdtemp_write_16(struct sdtemp_softc *, uint8_t, uint16_t);
     77 static uint32_t	sdtemp_decode_temp(struct sdtemp_softc *, uint16_t);
     78 static bool	sdtemp_pmf_suspend(device_t, const pmf_qual_t *);
     79 static bool	sdtemp_pmf_resume(device_t, const pmf_qual_t *);
     80 
     81 struct sdtemp_dev_entry {
     82 	const uint16_t sdtemp_mfg_id;
     83 	const uint16_t  sdtemp_devrev;
     84 	const uint16_t  sdtemp_mask;
     85 	const uint8_t  sdtemp_resolution;
     86 	const char    *sdtemp_desc;
     87 };
     88 
     89 /* Convert sysmon_envsys uKelvin value to simple degC */
     90 
     91 #define	__UK2C(uk) (((uk) - 273150000) / 1000000)
     92 
     93 /*
     94  * List of devices known to conform to JEDEC JC42.4
     95  *
     96  * NOTE: A non-negative value for resolution indicates that the sensor
     97  * resolution is fixed at that number of fractional bits;  a negative
     98  * value indicates that the sensor needs to be configured.  In either
     99  * case, trip-point registers are fixed at two-bit (0.25C) resolution.
    100  */
    101 static const struct sdtemp_dev_entry
    102 sdtemp_dev_table[] = {
    103     { MAXIM_MANUFACTURER_ID, MAX_6604_DEVICE_ID,    MAX_6604_MASK,   3,
    104 	"Maxim MAX6604" },
    105     { MCP_MANUFACTURER_ID,   MCP_9805_DEVICE_ID,    MCP_9805_MASK,   2,
    106 	"Microchip Tech MCP9805/MCP9843" },
    107     { MCP_MANUFACTURER_ID,   MCP_98243_DEVICE_ID,   MCP_98243_MASK, -4,
    108 	"Microchip Tech MCP98243" },
    109     { MCP_MANUFACTURER_ID,   MCP_98242_DEVICE_ID,   MCP_98242_MASK, -4,
    110 	"Microchip Tech MCP98242" },
    111     { ADT_MANUFACTURER_ID,   ADT_7408_DEVICE_ID,    ADT_7408_MASK,   4,
    112 	"Analog Devices ADT7408" },
    113     { NXP_MANUFACTURER_ID,   NXP_SE98_DEVICE_ID,    NXP_SE98_MASK,   3,
    114 	"NXP Semiconductors SE97B/SE98" },
    115     { NXP_MANUFACTURER_ID,   NXP_SE97_DEVICE_ID,    NXP_SE97_MASK,   3,
    116 	"NXP Semiconductors SE97" },
    117     { STTS_MANUFACTURER_ID,  STTS_424E_DEVICE_ID,   STTS_424E_MASK,  2,
    118 	"STmicroelectronics STTS424E" },
    119     { STTS_MANUFACTURER_ID,  STTS_424_DEVICE_ID,    STTS_424_MASK,   2,
    120 	"STmicroelectronics STTS424" },
    121     { CAT_MANUFACTURER_ID,   CAT_34TS02_DEVICE_ID,  CAT_34TS02_MASK, 4,
    122 	"Catalyst CAT34TS02/CAT6095" },
    123     { IDT_MANUFACTURER_ID,   IDT_TS3000B3_DEVICE_ID, IDT_TS3000B3_MASK, 4,
    124 	"Integrated Device Technology TS3000B3/TSE2002B3" },
    125     { 0, 0, 0, 2, "Unknown" }
    126 };
    127 
    128 static int
    129 sdtemp_lookup(uint16_t mfg, uint16_t devrev)
    130 {
    131 	int i;
    132 
    133 	for (i = 0; sdtemp_dev_table[i].sdtemp_mfg_id; i++) {
    134 		if (mfg != sdtemp_dev_table[i].sdtemp_mfg_id)
    135 			continue;
    136 		if ((devrev & sdtemp_dev_table[i].sdtemp_mask) ==
    137 		    sdtemp_dev_table[i].sdtemp_devrev)
    138 			break;
    139 	}
    140 
    141 	return i;
    142 }
    143 
    144 static int
    145 sdtemp_match(device_t parent, cfdata_t cf, void *aux)
    146 {
    147 	struct i2c_attach_args *ia = aux;
    148 	uint16_t mfgid, devid;
    149 	struct sdtemp_softc sc;
    150 	int i, error;
    151 
    152 	sc.sc_tag = ia->ia_tag;
    153 	sc.sc_address = ia->ia_addr;
    154 
    155 	if ((ia->ia_addr & SDTEMP_ADDRMASK) != SDTEMP_ADDR)
    156 		return 0;
    157 
    158 	/* Verify that we can read the manufacturer ID  & Device ID */
    159 	iic_acquire_bus(sc.sc_tag, 0);
    160 	error = sdtemp_read_16(&sc, SDTEMP_REG_MFG_ID,  &mfgid) |
    161 		sdtemp_read_16(&sc, SDTEMP_REG_DEV_REV, &devid);
    162 	iic_release_bus(sc.sc_tag, 0);
    163 
    164 	if (error)
    165 		return 0;
    166 
    167 	i = sdtemp_lookup(mfgid, devid);
    168 	if (sdtemp_dev_table[i].sdtemp_mfg_id == 0) {
    169 		aprint_debug("sdtemp: No match for mfg 0x%04x dev 0x%02x "
    170 		    "rev 0x%02x at address 0x%02x\n", mfgid, devid >> 8,
    171 		    devid & 0xff, sc.sc_address);
    172 		return 0;
    173 	}
    174 
    175 	return 1;
    176 }
    177 
    178 static void
    179 sdtemp_attach(device_t parent, device_t self, void *aux)
    180 {
    181 	struct sdtemp_softc *sc = device_private(self);
    182 	struct i2c_attach_args *ia = aux;
    183 	uint16_t mfgid, devid;
    184 	int i, error;
    185 
    186 	sc->sc_tag = ia->ia_tag;
    187 	sc->sc_address = ia->ia_addr;
    188 	sc->sc_dev = self;
    189 
    190 	iic_acquire_bus(sc->sc_tag, 0);
    191 	if ((error = sdtemp_read_16(sc, SDTEMP_REG_MFG_ID,  &mfgid)) != 0 ||
    192 	    (error = sdtemp_read_16(sc, SDTEMP_REG_DEV_REV, &devid)) != 0) {
    193 		iic_release_bus(sc->sc_tag, 0);
    194 		aprint_error(": attach error %d\n", error);
    195 		return;
    196 	}
    197 	i = sdtemp_lookup(mfgid, devid);
    198 	sc->sc_resolution =
    199 	    sdtemp_dev_table[i].sdtemp_resolution;
    200 
    201 	aprint_naive(": Temp Sensor\n");
    202 	aprint_normal(": %s Temp Sensor\n", sdtemp_dev_table[i].sdtemp_desc);
    203 
    204 	if (sdtemp_dev_table[i].sdtemp_mfg_id == 0)
    205 		aprint_debug_dev(self,
    206 		    "mfg 0x%04x dev 0x%02x rev 0x%02x at addr 0x%02x\n",
    207 		    mfgid, devid >> 8, devid & 0xff, ia->ia_addr);
    208 
    209 	/*
    210 	 * Alarm capability is required;  if not present, this is likely
    211 	 * not a real sdtemp device.
    212 	 */
    213 	error = sdtemp_read_16(sc, SDTEMP_REG_CAPABILITY, &sc->sc_capability);
    214 	if (error != 0 || (sc->sc_capability & SDTEMP_CAP_HAS_ALARM) == 0) {
    215 		iic_release_bus(sc->sc_tag, 0);
    216 		aprint_error_dev(self,
    217 		    "required alarm capability not present!\n");
    218 		return;
    219 	}
    220 	/* Set the configuration to defaults. */
    221 	error = sdtemp_write_16(sc, SDTEMP_REG_CONFIG, 0);
    222 	if (error != 0) {
    223 		iic_release_bus(sc->sc_tag, 0);
    224 		aprint_error_dev(self, "error %d writing config register\n",
    225 		    error);
    226 		return;
    227 	}
    228 	/* If variable resolution, set to max */
    229 	if (sc->sc_resolution < 0) {
    230 		sc->sc_resolution = ~sc->sc_resolution;
    231 		error = sdtemp_write_16(sc, SDTEMP_REG_RESOLUTION,
    232 					sc->sc_resolution & 0x3);
    233 		if (error != 0) {
    234 			iic_release_bus(sc->sc_tag, 0);
    235 			aprint_error_dev(self,
    236 			    "error %d writing resolution register\n", error);
    237 			return;
    238 		} else
    239 			sc->sc_resolution++;
    240 	}
    241 	iic_release_bus(sc->sc_tag, 0);
    242 
    243 	/* Hook us into the sysmon_envsys subsystem */
    244 	sc->sc_sme = sysmon_envsys_create();
    245 	sc->sc_sme->sme_name = device_xname(self);
    246 	sc->sc_sme->sme_cookie = sc;
    247 	sc->sc_sme->sme_refresh = sdtemp_refresh;
    248 	sc->sc_sme->sme_get_limits = sdtemp_get_limits;
    249 	sc->sc_sme->sme_set_limits = sdtemp_set_limits;
    250 
    251 	sc->sc_sensor = kmem_zalloc(sizeof(envsys_data_t), KM_NOSLEEP);
    252 	if (!sc->sc_sensor) {
    253 		aprint_error_dev(self, "unable to allocate sc_sensor\n");
    254 		goto bad2;
    255 	}
    256 
    257 	/* Initialize sensor data. */
    258 	sc->sc_sensor->units =  ENVSYS_STEMP;
    259 	sc->sc_sensor->state = ENVSYS_SINVALID;
    260 	sc->sc_sensor->flags |= ENVSYS_FMONLIMITS;
    261 	(void)strlcpy(sc->sc_sensor->desc, device_xname(self),
    262 	    sizeof(sc->sc_sensor->desc));
    263 
    264 	/* Now attach the sensor */
    265 	if (sysmon_envsys_sensor_attach(sc->sc_sme, sc->sc_sensor)) {
    266 		aprint_error_dev(self, "unable to attach sensor\n");
    267 		goto bad;
    268 	}
    269 
    270 	/* Register the device */
    271 	error = sysmon_envsys_register(sc->sc_sme);
    272 	if (error) {
    273 		aprint_error_dev(self, "error %d registering with sysmon\n",
    274 		    error);
    275 		goto bad;
    276 	}
    277 
    278 	if (!pmf_device_register(self, sdtemp_pmf_suspend, sdtemp_pmf_resume))
    279 		aprint_error_dev(self, "couldn't establish power handler\n");
    280 
    281 	/* Retrieve and display hardware monitor limits */
    282 	sdtemp_get_limits(sc->sc_sme, sc->sc_sensor, &sc->sc_deflims,
    283 	    &sc->sc_defprops);
    284 	aprint_normal_dev(self, "");
    285 	i = 0;
    286 	if (sc->sc_defprops & PROP_WARNMIN) {
    287 		aprint_normal("low limit %dC",
    288 		              __UK2C(sc->sc_deflims.sel_warnmin));
    289 		i++;
    290 	}
    291 	if (sc->sc_defprops & PROP_WARNMAX) {
    292 		aprint_normal("%shigh limit %dC ", (i)?", ":"",
    293 			      __UK2C(sc->sc_deflims.sel_warnmax));
    294 		i++;
    295 	}
    296 	if (sc->sc_defprops & PROP_CRITMAX) {
    297 		aprint_normal("%scritical limit %dC ", (i)?", ":"",
    298 			      __UK2C(sc->sc_deflims.sel_critmax));
    299 		i++;
    300 	}
    301 	if (i == 0)
    302 		aprint_normal("no hardware limits set\n");
    303 	else
    304 		aprint_normal("\n");
    305 
    306 	return;
    307 
    308 bad:
    309 	kmem_free(sc->sc_sensor, sizeof(envsys_data_t));
    310 bad2:
    311 	sysmon_envsys_destroy(sc->sc_sme);
    312 }
    313 
    314 /* Retrieve current limits from device, and encode in uKelvins */
    315 static void
    316 sdtemp_get_limits(struct sysmon_envsys *sme, envsys_data_t *edata,
    317 		  sysmon_envsys_lim_t *limits, uint32_t *props)
    318 {
    319 	struct sdtemp_softc *sc = sme->sme_cookie;
    320 	uint16_t lim;
    321 
    322 	*props = 0;
    323 	iic_acquire_bus(sc->sc_tag, 0);
    324 	if (sdtemp_read_16(sc, SDTEMP_REG_LOWER_LIM, &lim) == 0 && lim != 0) {
    325 		limits->sel_warnmin = sdtemp_decode_temp(sc, lim);
    326 		*props |= PROP_WARNMIN;
    327 	}
    328 	if (sdtemp_read_16(sc, SDTEMP_REG_UPPER_LIM, &lim) == 0 && lim != 0) {
    329 		limits->sel_warnmax = sdtemp_decode_temp(sc, lim);
    330 		*props |= PROP_WARNMAX;
    331 	}
    332 	if (sdtemp_read_16(sc, SDTEMP_REG_CRIT_LIM, &lim) == 0 && lim != 0) {
    333 		limits->sel_critmax = sdtemp_decode_temp(sc, lim);
    334 		*props |= PROP_CRITMAX;
    335 	}
    336 	iic_release_bus(sc->sc_tag, 0);
    337 	if (*props != 0)
    338 		*props |= PROP_DRIVER_LIMITS;
    339 }
    340 
    341 /* Send current limit values to the device */
    342 static void
    343 sdtemp_set_limits(struct sysmon_envsys *sme, envsys_data_t *edata,
    344 		  sysmon_envsys_lim_t *limits, uint32_t *props)
    345 {
    346 	uint16_t val;
    347 	struct sdtemp_softc *sc = sme->sme_cookie;
    348 
    349 	if (limits == NULL) {
    350 		limits = &sc->sc_deflims;
    351 		props  = &sc->sc_defprops;
    352 	}
    353 	iic_acquire_bus(sc->sc_tag, 0);
    354 	if (*props & PROP_WARNMIN) {
    355 		val = __UK2C(limits->sel_warnmin);
    356 		(void)sdtemp_write_16(sc, SDTEMP_REG_LOWER_LIM,
    357 					(val << 4) & SDTEMP_TEMP_MASK);
    358 	}
    359 	if (*props & PROP_WARNMAX) {
    360 		val = __UK2C(limits->sel_warnmax);
    361 		(void)sdtemp_write_16(sc, SDTEMP_REG_UPPER_LIM,
    362 					(val << 4) & SDTEMP_TEMP_MASK);
    363 	}
    364 	if (*props & PROP_CRITMAX) {
    365 		val = __UK2C(limits->sel_critmax);
    366 		(void)sdtemp_write_16(sc, SDTEMP_REG_CRIT_LIM,
    367 					(val << 4) & SDTEMP_TEMP_MASK);
    368 	}
    369 	iic_release_bus(sc->sc_tag, 0);
    370 
    371 	/*
    372 	 * If at least one limit is set that we can handle, and no
    373 	 * limits are set that we cannot handle, tell sysmon that
    374 	 * the driver will take care of monitoring the limits!
    375 	 */
    376 	if (*props & (PROP_CRITMIN | PROP_BATTCAP | PROP_BATTWARN))
    377 		*props &= ~PROP_DRIVER_LIMITS;
    378 	else if (*props & PROP_LIMITS)
    379 		*props |= PROP_DRIVER_LIMITS;
    380 	else
    381 		*props &= ~PROP_DRIVER_LIMITS;
    382 }
    383 
    384 #ifdef NOT_YET	/* All registers on these sensors are 16-bits */
    385 
    386 /* Read a 8-bit value from a register */
    387 static int
    388 sdtemp_read_8(struct sdtemp_softc *sc, uint8_t reg, uint8_t *valp)
    389 {
    390 	int error;
    391 
    392 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
    393 	    sc->sc_address, &reg, 1, valp, sizeof(*valp), 0);
    394 
    395 	return error;
    396 }
    397 
    398 static int
    399 sdtemp_write_8(struct sdtemp_softc *sc, uint8_t reg, uint8_t val)
    400 {
    401 	return iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
    402 	    sc->sc_address, &reg, 1, &val, sizeof(val), 0);
    403 }
    404 #endif /* NOT_YET */
    405 
    406 /* Read a 16-bit value from a register */
    407 static int
    408 sdtemp_read_16(struct sdtemp_softc *sc, uint8_t reg, uint16_t *valp)
    409 {
    410 	int error;
    411 
    412 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
    413 	    sc->sc_address, &reg, 1, valp, sizeof(*valp), 0);
    414 	if (error)
    415 		return error;
    416 
    417 	*valp = be16toh(*valp);
    418 
    419 	return 0;
    420 }
    421 
    422 static int
    423 sdtemp_write_16(struct sdtemp_softc *sc, uint8_t reg, uint16_t val)
    424 {
    425 	uint16_t temp;
    426 
    427 	temp = htobe16(val);
    428 	return iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
    429 	    sc->sc_address, &reg, 1, &temp, sizeof(temp), 0);
    430 }
    431 
    432 static uint32_t
    433 sdtemp_decode_temp(struct sdtemp_softc *sc, uint16_t temp)
    434 {
    435 	uint32_t val;
    436 	int32_t stemp;
    437 
    438 	/* Get only the temperature bits */
    439 	temp &= SDTEMP_TEMP_MASK;
    440 
    441 	/* If necessary, extend the sign bit */
    442 	if ((sc->sc_capability & SDTEMP_CAP_WIDER_RANGE) &&
    443 	    (temp & SDTEMP_TEMP_NEGATIVE))
    444 		temp |= SDTEMP_TEMP_SIGN_EXT;
    445 
    446 	/* Mask off only bits valid within current resolution */
    447 	temp &= ~(0xf >> sc->sc_resolution);
    448 
    449 	/* Treat as signed and extend to 32-bits */
    450 	stemp = (int16_t)temp;
    451 
    452 	/* Now convert from 0.0625 (1/16) deg C increments to microKelvins */
    453 	val = (stemp * 62500) + 273150000;
    454 
    455 	return val;
    456 }
    457 
    458 static void
    459 sdtemp_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
    460 {
    461 	struct sdtemp_softc *sc = sme->sme_cookie;
    462 	uint16_t val;
    463 	int error;
    464 
    465 	iic_acquire_bus(sc->sc_tag, 0);
    466 	error = sdtemp_read_16(sc, SDTEMP_REG_AMBIENT_TEMP, &val);
    467 	iic_release_bus(sc->sc_tag, 0);
    468 
    469 	if (error) {
    470 		edata->state = ENVSYS_SINVALID;
    471 		return;
    472 	}
    473 
    474 	edata->value_cur = sdtemp_decode_temp(sc, val);
    475 
    476 	/* Now check for limits */
    477 	if ((edata->upropset & PROP_DRIVER_LIMITS) == 0)
    478 		edata->state = ENVSYS_SVALID;
    479 	else if ((val & SDTEMP_ABOVE_CRIT) &&
    480 		    (edata->upropset & PROP_CRITMAX))
    481 		edata->state = ENVSYS_SCRITOVER;
    482 	else if ((val & SDTEMP_ABOVE_UPPER) &&
    483 		    (edata->upropset & PROP_WARNMAX))
    484 		edata->state = ENVSYS_SWARNOVER;
    485 	else if ((val & SDTEMP_BELOW_LOWER) &&
    486 		    (edata->upropset & PROP_WARNMIN))
    487 		edata->state = ENVSYS_SWARNUNDER;
    488 	else
    489 		edata->state = ENVSYS_SVALID;
    490 }
    491 
    492 /*
    493  * power management functions
    494  *
    495  * We go into "shutdown" mode at suspend time, and return to normal
    496  * mode upon resume.  This reduces power consumption by disabling
    497  * the A/D converter.
    498  */
    499 
    500 static bool
    501 sdtemp_pmf_suspend(device_t dev, const pmf_qual_t *qual)
    502 {
    503 	struct sdtemp_softc *sc = device_private(dev);
    504 	int error;
    505 	uint16_t config;
    506 
    507 	iic_acquire_bus(sc->sc_tag, 0);
    508 	error = sdtemp_read_16(sc, SDTEMP_REG_CONFIG, &config);
    509 	if (error == 0) {
    510 		config |= SDTEMP_CONFIG_SHUTDOWN_MODE;
    511 		error = sdtemp_write_16(sc, SDTEMP_REG_CONFIG, config);
    512 	}
    513 	iic_release_bus(sc->sc_tag, 0);
    514 	return (error == 0);
    515 }
    516 
    517 static bool
    518 sdtemp_pmf_resume(device_t dev, const pmf_qual_t *qual)
    519 {
    520 	struct sdtemp_softc *sc = device_private(dev);
    521 	int error;
    522 	uint16_t config;
    523 
    524 	iic_acquire_bus(sc->sc_tag, 0);
    525 	error = sdtemp_read_16(sc, SDTEMP_REG_CONFIG, &config);
    526 	if (error == 0) {
    527 		config &= ~SDTEMP_CONFIG_SHUTDOWN_MODE;
    528 		error = sdtemp_write_16(sc, SDTEMP_REG_CONFIG, config);
    529 	}
    530 	iic_release_bus(sc->sc_tag, 0);
    531 	return (error == 0);
    532 }
    533