xref: /netbsd-src/sys/dev/i2c/sdtemp.c (revision 181254a7b1bdde6873432bffef2d2decc4b5c22f)
1 /*      $NetBSD: sdtemp.c,v 1.39 2020/06/30 19:02:42 msaitoh 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 1.39 2020/06/30 19:02:42 msaitoh 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 #include <sys/module.h>
42 
43 #include <dev/sysmon/sysmonvar.h>
44 
45 #include <dev/i2c/i2cvar.h>
46 #include <dev/i2c/sdtemp_reg.h>
47 
48 struct sdtemp_softc {
49 	device_t sc_dev;
50 	i2c_tag_t sc_tag;
51 	int sc_address;
52 
53 	struct sysmon_envsys *sc_sme;
54 	envsys_data_t *sc_sensor;
55 	sysmon_envsys_lim_t sc_deflims;
56 	uint32_t sc_defprops;
57 	int sc_resolution;
58 	uint16_t sc_mfgid;
59 	uint16_t sc_devid;
60 	uint16_t sc_devid_masked;
61 	uint16_t sc_capability;
62 };
63 
64 static int  sdtemp_match(device_t, cfdata_t, void *);
65 static void sdtemp_attach(device_t, device_t, void *);
66 static int  sdtemp_detach(device_t, int);
67 
68 CFATTACH_DECL_NEW(sdtemp, sizeof(struct sdtemp_softc),
69 	sdtemp_match, sdtemp_attach, sdtemp_detach, NULL);
70 
71 static void	sdtemp_refresh(struct sysmon_envsys *, envsys_data_t *);
72 static void	sdtemp_get_limits(struct sysmon_envsys *, envsys_data_t *,
73 				  sysmon_envsys_lim_t *, uint32_t *);
74 static void	sdtemp_set_limits(struct sysmon_envsys *, envsys_data_t *,
75 				  sysmon_envsys_lim_t *, uint32_t *);
76 #ifdef NOT_YET
77 static int	sdtemp_read_8(struct sdtemp_softc *, uint8_t, uint8_t *);
78 static int	sdtemp_write_8(struct sdtemp_softc *, uint8_t, uint8_t);
79 #endif /* NOT YET */
80 static int	sdtemp_read_16(struct sdtemp_softc *, uint8_t, uint16_t *);
81 static int	sdtemp_write_16(struct sdtemp_softc *, uint8_t, uint16_t);
82 static uint32_t	sdtemp_decode_temp(struct sdtemp_softc *, uint16_t);
83 static bool	sdtemp_pmf_suspend(device_t, const pmf_qual_t *);
84 static bool	sdtemp_pmf_resume(device_t, const pmf_qual_t *);
85 /* Device dependent config functions */
86 static void	sdtemp_config_mcp(struct sdtemp_softc *);
87 static void	sdtemp_config_idt(struct sdtemp_softc *);
88 
89 struct sdtemp_dev_entry {
90 	const uint16_t sdtemp_mfg_id;
91 	const uint16_t sdtemp_devrev;
92 	const uint16_t sdtemp_mask;
93 	void         (*sdtemp_config)(struct sdtemp_softc *);
94 	const char    *sdtemp_desc;
95 };
96 
97 /* Convert sysmon_envsys uKelvin value to simple degC */
98 
99 #define	__UK2C(uk) (((uk) - 273150000) / 1000000)
100 
101 /* List of devices known to conform to JEDEC JC42.4 */
102 
103 #define	CMCP sdtemp_config_mcp
104 #define	CIDT sdtemp_config_idt
105 
106 static const struct sdtemp_dev_entry
107 sdtemp_dev_table[] = {
108     { AT_MANUFACTURER_ID,   AT_30TS00_DEVICE_ID,     AT_30TS00_MASK,	  NULL,
109 	"Atmel AT30TS00" },
110     { AT2_MANUFACTURER_ID,  AT2_30TSE004_DEVICE_ID,  AT2_30TSE004_MASK,	  NULL,
111 	"Atmel AT30TSE004" },
112     { GT_MANUFACTURER_ID,   GT_30TS00_DEVICE_ID,     GT_30TS00_MASK,	  NULL,
113 	"Giantec GT30TS00" },
114     { GT2_MANUFACTURER_ID,  GT2_34TS02_DEVICE_ID,    GT2_34TS02_MASK,	  NULL,
115 	"Giantec GT34TS02" },
116     { MAXIM_MANUFACTURER_ID, MAX_6604_DEVICE_ID,     MAX_6604_MASK,	  NULL,
117 	"Maxim MAX6604" },
118     { MAXIM_MANUFACTURER_ID, MAX_6604_2_DEVICE_ID,   MAX_6604_MASK,	  NULL,
119 	"Maxim MAX6604" },
120     { MCP_MANUFACTURER_ID,  MCP_9804_DEVICE_ID,	     MCP_9804_MASK,	  CMCP,
121 	"Microchip Tech MCP9804" },
122     { MCP_MANUFACTURER_ID,  MCP_9805_DEVICE_ID,	     MCP_9805_MASK,	  NULL,
123 	"Microchip Tech MCP9805/MCP9843" },
124     { MCP_MANUFACTURER_ID,  MCP_98242_DEVICE_ID,     MCP_98242_MASK,	  CMCP,
125 	"Microchip Tech MCP98242" },
126     { MCP_MANUFACTURER_ID,  MCP_98243_DEVICE_ID,     MCP_98243_MASK,	  CMCP,
127 	"Microchip Tech MCP98243" },
128     { MCP_MANUFACTURER_ID,  MCP_98244_DEVICE_ID,     MCP_98244_MASK,	  CMCP,
129 	"Microchip Tech MCP98244" },
130     { MCP2_MANUFACTURER_ID, MCP2_EMC1501_DEVICE_ID,  MCP2_EMC1501_MASK,	  NULL,
131 	"Microchip Tech EMC1501" },
132     { ADT_MANUFACTURER_ID,  ADT_7408_DEVICE_ID,	     ADT_7408_MASK,	  NULL,
133 	"Analog Devices ADT7408" },
134     { NXP_MANUFACTURER_ID,  NXP_SE98_DEVICE_ID,	     NXP_SE98_MASK,	  NULL,
135 	"NXP Semiconductors SE97B/SE98" },
136     { NXP_MANUFACTURER_ID,  NXP_SE97_DEVICE_ID,	     NXP_SE97_MASK,	  NULL,
137 	"NXP Semiconductors SE97" },
138     { STTS_MANUFACTURER_ID, STTS_424E_DEVICE_ID,     STTS_424E_MASK,	  NULL,
139 	"STmicroelectronics STTS424E" },
140     { STTS_MANUFACTURER_ID, STTS_424_DEVICE_ID,	     STTS_424_MASK,	  NULL,
141 	"STmicroelectronics STTS424" },
142     { STTS_MANUFACTURER_ID, STTS_2002_DEVICE_ID,     STTS_2002_MASK,	  NULL,
143 	"STmicroelectronics STTS2002" },
144     { STTS_MANUFACTURER_ID, STTS_2004_DEVICE_ID,     STTS_2004_MASK,	  NULL,
145 	"STmicroelectronics STTS2004" },
146     { STTS_MANUFACTURER_ID, STTS_3000_DEVICE_ID,     STTS_3000_MASK,	  NULL,
147 	"STmicroelectronics STTS3000" },
148     { CAT_MANUFACTURER_ID,  CAT_34TS02_DEVICE_ID,    CAT_34TS02_MASK,	  NULL,
149 	"Catalyst CAT34TS02/CAT6095" },
150     { CAT_MANUFACTURER_ID,  CAT_34TS02C_DEVICE_ID,   CAT_34TS02C_MASK,	  NULL,
151 	"Catalyst CAT34TS02C" },
152     { CAT_MANUFACTURER_ID,  CAT_34TS04_DEVICE_ID,    CAT_34TS04_MASK,	  NULL,
153 	"Catalyst CAT34TS04" },
154     { IDT_MANUFACTURER_ID,  IDT_TSE2004GB2_DEVICE_ID,IDT_TSE2004GB2_MASK, NULL,
155 	"Integrated Device Technology TSE2004GB2" },
156     { IDT_MANUFACTURER_ID,  IDT_TS3000B3_DEVICE_ID,  IDT_TS3000B3_MASK,	  CIDT,
157 	"Integrated Device Technology TS3000B3/TSE2002B3" },
158     { IDT_MANUFACTURER_ID,  IDT_TS3000GB0_DEVICE_ID, IDT_TS3000GB0_MASK,  CIDT,
159 	"Integrated Device Technology TS3000GB0" },
160     { IDT_MANUFACTURER_ID,  IDT_TS3000GB2_DEVICE_ID, IDT_TS3000GB2_MASK,  CIDT,
161 	"Integrated Device Technology TS3000GB2" },
162     { IDT_MANUFACTURER_ID,  IDT_TS3001GB2_DEVICE_ID, IDT_TS3001GB2_MASK,  CIDT,
163 	"Integrated Device Technology TS3001GB2" },
164     /*
165      * Don't change the location of the following two entries. Device specific
166      * entry must be located at above.
167      */
168     { 0,		    TSE2004AV_ID,	     TSE2004AV_MASK,	  NULL,
169 	"TSE2004av compliant device (generic driver)" },
170     { 0, 0, 0, NULL, "Unknown" }
171 };
172 
173 #undef CMCP
174 #undef CIDT
175 
176 static const char *temp_resl[] = {
177 	"0.5C",
178 	"0.25C",
179 	"0.125C",
180 	"0.0625C"
181 };
182 
183 static int
184 sdtemp_lookup(uint16_t mfg, uint16_t devrev)
185 {
186 	int i;
187 
188 	for (i = 0; sdtemp_dev_table[i].sdtemp_mfg_id; i++) {
189 		if (mfg != sdtemp_dev_table[i].sdtemp_mfg_id)
190 			continue;
191 		if ((devrev & sdtemp_dev_table[i].sdtemp_mask) ==
192 		    sdtemp_dev_table[i].sdtemp_devrev)
193 			break;
194 	}
195 	/* Check TSE2004av */
196 	if ((sdtemp_dev_table[i].sdtemp_mfg_id == 0)
197 	    && (SDTEMP_IS_TSE2004AV(devrev) == 0))
198 			i++; /* Unknown */
199 
200 	return i;
201 }
202 
203 static int
204 sdtemp_match(device_t parent, cfdata_t cf, void *aux)
205 {
206 	struct i2c_attach_args *ia = aux;
207 	uint16_t mfgid, devid, cap;
208 	struct sdtemp_softc sc;
209 	int i, error;
210 
211 	sc.sc_tag = ia->ia_tag;
212 	sc.sc_address = ia->ia_addr;
213 
214 	if ((ia->ia_addr & SDTEMP_ADDRMASK) != SDTEMP_ADDR)
215 		return 0;
216 
217 	/*
218 	 * Verify that we can read the manufacturer ID, Device ID and the
219 	 * capability
220 	 */
221 	error = iic_acquire_bus(sc.sc_tag, 0);
222 	if (error)
223 		return 0;
224 	error = sdtemp_read_16(&sc, SDTEMP_REG_MFG_ID,  &mfgid) |
225 		sdtemp_read_16(&sc, SDTEMP_REG_DEV_REV, &devid) |
226 		sdtemp_read_16(&sc, SDTEMP_REG_CAPABILITY, &cap);
227 	iic_release_bus(sc.sc_tag, 0);
228 
229 	if (error)
230 		return 0;
231 
232 	i = sdtemp_lookup(mfgid, devid);
233 	if ((sdtemp_dev_table[i].sdtemp_mfg_id == 0) &&
234 	    (sdtemp_dev_table[i].sdtemp_devrev == 0)) {
235 		aprint_debug("sdtemp: No match for mfg 0x%04x dev 0x%02x "
236 		    "rev 0x%02x at address 0x%02x\n", mfgid, devid >> 8,
237 		    devid & 0xff, sc.sc_address);
238 		return 0;
239 	}
240 
241 	/*
242 	 * Check by SDTEMP_IS_TSE2004AV() might not be enough, so check the
243 	 * alarm capability, too.
244 	 */
245 	if ((cap & SDTEMP_CAP_HAS_ALARM) == 0)
246 		return 0;
247 
248 	return I2C_MATCH_ADDRESS_AND_PROBE;
249 }
250 
251 static void
252 sdtemp_attach(device_t parent, device_t self, void *aux)
253 {
254 	struct sdtemp_softc *sc = device_private(self);
255 	struct i2c_attach_args *ia = aux;
256 	uint16_t mfgid, devid;
257 	int i, error;
258 
259 	sc->sc_tag = ia->ia_tag;
260 	sc->sc_address = ia->ia_addr;
261 	sc->sc_dev = self;
262 
263 	error = iic_acquire_bus(sc->sc_tag, 0);
264 	if (error)
265 		return;
266 
267 	if ((error = sdtemp_read_16(sc, SDTEMP_REG_MFG_ID,  &mfgid)) != 0 ||
268 	    (error = sdtemp_read_16(sc, SDTEMP_REG_DEV_REV, &devid)) != 0) {
269 		iic_release_bus(sc->sc_tag, 0);
270 		aprint_error(": attach error %d\n", error);
271 		return;
272 	}
273 	sc->sc_mfgid = mfgid;
274 	sc->sc_devid = devid;
275 	i = sdtemp_lookup(mfgid, devid);
276 	sc->sc_devid_masked = devid & sdtemp_dev_table[i].sdtemp_mask;
277 
278 	aprint_naive(": Temp Sensor\n");
279 	aprint_normal(": %s Temp Sensor\n", sdtemp_dev_table[i].sdtemp_desc);
280 
281 	if (sdtemp_dev_table[i].sdtemp_mfg_id == 0) {
282 		if (SDTEMP_IS_TSE2004AV(devid))
283 			aprint_normal_dev(self, "TSE2004av compliant. "
284 			    "Manufacturer ID 0x%04hx, Device revision 0x%02x\n",
285 			    mfgid, devid & TSE2004AV_REV);
286 		else {
287 			aprint_error_dev(self,
288 			    "mfg 0x%04x dev 0x%02x rev 0x%02x at addr 0x%02x\n",
289 			    mfgid, devid >> 8, devid & 0xff, ia->ia_addr);
290 			iic_release_bus(sc->sc_tag, 0);
291 			aprint_error_dev(self, "It should no happen. "
292 			    "Why attach() found me?\n");
293 			return;
294 		}
295 	}
296 
297 	error = sdtemp_read_16(sc, SDTEMP_REG_CAPABILITY, &sc->sc_capability);
298 	aprint_debug_dev(self, "capability reg = %04x\n", sc->sc_capability);
299 	sc->sc_resolution
300 	    = __SHIFTOUT(sc->sc_capability, SDTEMP_CAP_RESOLUTION);
301 	/*
302 	 * Call device dependent function here. Currently, it's used for
303 	 * the resolution.
304 	 *
305 	 * IDT's devices and some Microchip's devices have the resolution
306 	 * register in the vendor specific registers area. The devices'
307 	 * resolution bits in the capability register are not the maximum
308 	 * resolution but the current value of the setting.
309 	 */
310 	if (sdtemp_dev_table[i].sdtemp_config != NULL)
311 		sdtemp_dev_table[i].sdtemp_config(sc);
312 
313 	aprint_normal_dev(self, "%s accuracy",
314 	    (sc->sc_capability & SDTEMP_CAP_ACCURACY_1C) ? "high" : "default");
315 	if ((sc->sc_capability & SDTEMP_CAP_WIDER_RANGE) != 0)
316 		aprint_normal(", wider range");
317 	aprint_normal(", %s resolution", temp_resl[sc->sc_resolution]);
318 	if ((sc->sc_capability & SDTEMP_CAP_VHV) != 0)
319 		aprint_debug(", high voltage standoff");
320 	aprint_debug(", %s timeout",
321 	    (sc->sc_capability & SDTEMP_CAP_TMOUT) ? "25-35ms" : "10-60ms");
322 	if ((sc->sc_capability & SDTEMP_CAP_EVSD) != 0)
323 		aprint_normal(", event with shutdown");
324 	aprint_normal("\n");
325 	/*
326 	 * Alarm capability is required;  if not present, this is likely
327 	 * not a real sdtemp device.
328 	 */
329 	if (error != 0 || (sc->sc_capability & SDTEMP_CAP_HAS_ALARM) == 0) {
330 		iic_release_bus(sc->sc_tag, 0);
331 		aprint_error_dev(self,
332 		    "required alarm capability not present!\n");
333 		return;
334 	}
335 	/* Set the configuration to defaults. */
336 	error = sdtemp_write_16(sc, SDTEMP_REG_CONFIG, 0);
337 	if (error != 0) {
338 		iic_release_bus(sc->sc_tag, 0);
339 		aprint_error_dev(self, "error %d writing config register\n",
340 		    error);
341 		return;
342 	}
343 	iic_release_bus(sc->sc_tag, 0);
344 
345 	/* Hook us into the sysmon_envsys subsystem */
346 	sc->sc_sme = sysmon_envsys_create();
347 	sc->sc_sme->sme_name = device_xname(self);
348 	sc->sc_sme->sme_cookie = sc;
349 	sc->sc_sme->sme_refresh = sdtemp_refresh;
350 	sc->sc_sme->sme_get_limits = sdtemp_get_limits;
351 	sc->sc_sme->sme_set_limits = sdtemp_set_limits;
352 
353 	sc->sc_sensor = kmem_zalloc(sizeof(envsys_data_t), KM_SLEEP);
354 
355 	/* Initialize sensor data. */
356 	sc->sc_sensor->units =  ENVSYS_STEMP;
357 	sc->sc_sensor->state = ENVSYS_SINVALID;
358 	sc->sc_sensor->flags |= ENVSYS_FMONLIMITS;
359 	(void)strlcpy(sc->sc_sensor->desc, device_xname(self),
360 	    sizeof(sc->sc_sensor->desc));
361 	snprintf(sc->sc_sensor->desc, sizeof(sc->sc_sensor->desc),
362 	    "DIMM %d temperature", sc->sc_address - SDTEMP_ADDR);
363 
364 	/* Now attach the sensor */
365 	if (sysmon_envsys_sensor_attach(sc->sc_sme, sc->sc_sensor)) {
366 		aprint_error_dev(self, "unable to attach sensor\n");
367 		goto bad;
368 	}
369 
370 	/* Register the device */
371 	error = sysmon_envsys_register(sc->sc_sme);
372 	if (error) {
373 		aprint_error_dev(self, "error %d registering with sysmon\n",
374 		    error);
375 		goto bad;
376 	}
377 
378 	if (!pmf_device_register(self, sdtemp_pmf_suspend, sdtemp_pmf_resume))
379 		aprint_error_dev(self, "couldn't establish power handler\n");
380 
381 	/* Retrieve and display hardware monitor limits */
382 	sdtemp_get_limits(sc->sc_sme, sc->sc_sensor, &sc->sc_deflims,
383 	    &sc->sc_defprops);
384 	aprint_normal_dev(self, "Hardware limits: ");
385 	i = 0;
386 	if (sc->sc_defprops & PROP_WARNMIN) {
387 		aprint_normal("low %dC",
388 		              __UK2C(sc->sc_deflims.sel_warnmin));
389 		i++;
390 	}
391 	if (sc->sc_defprops & PROP_WARNMAX) {
392 		aprint_normal("%shigh %dC ", (i)?", ":"",
393 			      __UK2C(sc->sc_deflims.sel_warnmax));
394 		i++;
395 	}
396 	if (sc->sc_defprops & PROP_CRITMAX) {
397 		aprint_normal("%scritical %dC ", (i)?", ":"",
398 			      __UK2C(sc->sc_deflims.sel_critmax));
399 		i++;
400 	}
401 	aprint_normal("%s\n", (i)?"":"none set");
402 
403 	return;
404 
405 bad:
406 	kmem_free(sc->sc_sensor, sizeof(envsys_data_t));
407 	sysmon_envsys_destroy(sc->sc_sme);
408 }
409 
410 static int
411 sdtemp_detach(device_t self, int flags)
412 {
413 	struct sdtemp_softc *sc = device_private(self);
414 
415 	pmf_device_deregister(self);
416 
417 	if (sc->sc_sme)
418 		sysmon_envsys_unregister(sc->sc_sme);
419 	if (sc->sc_sensor)
420 		kmem_free(sc->sc_sensor, sizeof(envsys_data_t));
421 
422 	return 0;
423 }
424 
425 /* Retrieve current limits from device, and encode in uKelvins */
426 static void
427 sdtemp_get_limits(struct sysmon_envsys *sme, envsys_data_t *edata,
428 		  sysmon_envsys_lim_t *limits, uint32_t *props)
429 {
430 	struct sdtemp_softc *sc = sme->sme_cookie;
431 	uint16_t lim;
432 
433 	*props = 0;
434 	if (iic_acquire_bus(sc->sc_tag, 0) != 0)
435 		return;
436 
437 	if (sdtemp_read_16(sc, SDTEMP_REG_LOWER_LIM, &lim) == 0 && lim != 0) {
438 		limits->sel_warnmin = sdtemp_decode_temp(sc, lim);
439 		*props |= PROP_WARNMIN;
440 	}
441 	if (sdtemp_read_16(sc, SDTEMP_REG_UPPER_LIM, &lim) == 0 && lim != 0) {
442 		limits->sel_warnmax = sdtemp_decode_temp(sc, lim);
443 		*props |= PROP_WARNMAX;
444 	}
445 	if (sdtemp_read_16(sc, SDTEMP_REG_CRIT_LIM, &lim) == 0 && lim != 0) {
446 		limits->sel_critmax = sdtemp_decode_temp(sc, lim);
447 		*props |= PROP_CRITMAX;
448 	}
449 	iic_release_bus(sc->sc_tag, 0);
450 	if (*props != 0)
451 		*props |= PROP_DRIVER_LIMITS;
452 }
453 
454 /* Send current limit values to the device */
455 static void
456 sdtemp_set_limits(struct sysmon_envsys *sme, envsys_data_t *edata,
457 		  sysmon_envsys_lim_t *limits, uint32_t *props)
458 {
459 	uint16_t val;
460 	struct sdtemp_softc *sc = sme->sme_cookie;
461 
462 	if (limits == NULL) {
463 		limits = &sc->sc_deflims;
464 		props  = &sc->sc_defprops;
465 	}
466 	if (iic_acquire_bus(sc->sc_tag, 0) != 0)
467 		return;
468 
469 	if (*props & PROP_WARNMIN) {
470 		val = __UK2C(limits->sel_warnmin);
471 		(void)sdtemp_write_16(sc, SDTEMP_REG_LOWER_LIM,
472 					(val << 4) & SDTEMP_TEMP_MASK);
473 	}
474 	if (*props & PROP_WARNMAX) {
475 		val = __UK2C(limits->sel_warnmax);
476 		(void)sdtemp_write_16(sc, SDTEMP_REG_UPPER_LIM,
477 					(val << 4) & SDTEMP_TEMP_MASK);
478 	}
479 	if (*props & PROP_CRITMAX) {
480 		val = __UK2C(limits->sel_critmax);
481 		(void)sdtemp_write_16(sc, SDTEMP_REG_CRIT_LIM,
482 					(val << 4) & SDTEMP_TEMP_MASK);
483 	}
484 	iic_release_bus(sc->sc_tag, 0);
485 
486 	/*
487 	 * If at least one limit is set that we can handle, and no
488 	 * limits are set that we cannot handle, tell sysmon that
489 	 * the driver will take care of monitoring the limits!
490 	 */
491 	if (*props & (PROP_CRITMIN | PROP_BATTCAP | PROP_BATTWARN))
492 		*props &= ~PROP_DRIVER_LIMITS;
493 	else if (*props & PROP_LIMITS)
494 		*props |= PROP_DRIVER_LIMITS;
495 	else
496 		*props &= ~PROP_DRIVER_LIMITS;
497 }
498 
499 #ifdef NOT_YET	/* All registers on these sensors are 16-bits */
500 
501 /* Read a 8-bit value from a register */
502 static int
503 sdtemp_read_8(struct sdtemp_softc *sc, uint8_t reg, uint8_t *valp)
504 {
505 	int error;
506 
507 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
508 	    sc->sc_address, &reg, 1, valp, sizeof(*valp), 0);
509 
510 	return error;
511 }
512 
513 static int
514 sdtemp_write_8(struct sdtemp_softc *sc, uint8_t reg, uint8_t val)
515 {
516 	return iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
517 	    sc->sc_address, &reg, 1, &val, sizeof(val), 0);
518 }
519 #endif /* NOT_YET */
520 
521 /* Read a 16-bit value from a register */
522 static int
523 sdtemp_read_16(struct sdtemp_softc *sc, uint8_t reg, uint16_t *valp)
524 {
525 	int error;
526 
527 	error = iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP,
528 	    sc->sc_address, &reg, 1, valp, sizeof(*valp), 0);
529 	if (error)
530 		return error;
531 
532 	*valp = be16toh(*valp);
533 
534 	return 0;
535 }
536 
537 static int
538 sdtemp_write_16(struct sdtemp_softc *sc, uint8_t reg, uint16_t val)
539 {
540 	uint16_t temp;
541 
542 	temp = htobe16(val);
543 	return iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP,
544 	    sc->sc_address, &reg, 1, &temp, sizeof(temp), 0);
545 }
546 
547 static uint32_t
548 sdtemp_decode_temp(struct sdtemp_softc *sc, uint16_t temp)
549 {
550 	uint32_t val;
551 	int32_t stemp;
552 
553 	/* Get only the temperature bits */
554 	temp &= SDTEMP_TEMP_MASK;
555 
556 	/* If necessary, extend the sign bit */
557 	if ((sc->sc_capability & SDTEMP_CAP_WIDER_RANGE) &&
558 	    (temp & SDTEMP_TEMP_NEGATIVE))
559 		temp |= SDTEMP_TEMP_SIGN_EXT;
560 
561 	/* Mask off only bits valid within current resolution */
562 	temp &= ~(0x7 >> sc->sc_resolution);
563 
564 	/* Treat as signed and extend to 32-bits */
565 	stemp = (int16_t)temp;
566 
567 	/* Now convert from 0.0625 (1/16) deg C increments to microKelvins */
568 	val = (stemp * 62500) + 273150000;
569 
570 	return val;
571 }
572 
573 static void
574 sdtemp_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
575 {
576 	struct sdtemp_softc *sc = sme->sme_cookie;
577 	uint16_t val;
578 	int error;
579 
580 	error = iic_acquire_bus(sc->sc_tag, 0);
581 	if (error) {
582 		edata->state = ENVSYS_SINVALID;
583 		return;
584 	}
585 
586 	error = sdtemp_read_16(sc, SDTEMP_REG_AMBIENT_TEMP, &val);
587 	iic_release_bus(sc->sc_tag, 0);
588 
589 	if (error) {
590 		edata->state = ENVSYS_SINVALID;
591 		return;
592 	}
593 
594 	edata->value_cur = sdtemp_decode_temp(sc, val);
595 
596 	/* Now check for limits */
597 	if ((edata->upropset & PROP_DRIVER_LIMITS) == 0)
598 		edata->state = ENVSYS_SVALID;
599 	else if ((val & SDTEMP_ABOVE_CRIT) &&
600 		    (edata->upropset & PROP_CRITMAX))
601 		edata->state = ENVSYS_SCRITOVER;
602 	else if ((val & SDTEMP_ABOVE_UPPER) &&
603 		    (edata->upropset & PROP_WARNMAX))
604 		edata->state = ENVSYS_SWARNOVER;
605 	else if ((val & SDTEMP_BELOW_LOWER) &&
606 		    (edata->upropset & PROP_WARNMIN))
607 		edata->state = ENVSYS_SWARNUNDER;
608 	else
609 		edata->state = ENVSYS_SVALID;
610 }
611 
612 /*
613  * Power management functions
614  *
615  * We go into "shutdown" mode at suspend time, and return to normal
616  * mode upon resume.  This reduces power consumption by disabling
617  * the A/D converter.
618  */
619 
620 static bool
621 sdtemp_pmf_suspend(device_t dev, const pmf_qual_t *qual)
622 {
623 	struct sdtemp_softc *sc = device_private(dev);
624 	int error;
625 	uint16_t config;
626 
627 	error = iic_acquire_bus(sc->sc_tag, 0);
628 	if (error != 0)
629 		return false;
630 
631 	error = sdtemp_read_16(sc, SDTEMP_REG_CONFIG, &config);
632 	if (error == 0) {
633 		config |= SDTEMP_CONFIG_SHUTDOWN_MODE;
634 		error = sdtemp_write_16(sc, SDTEMP_REG_CONFIG, config);
635 	}
636 	iic_release_bus(sc->sc_tag, 0);
637 	return (error == 0);
638 }
639 
640 static bool
641 sdtemp_pmf_resume(device_t dev, const pmf_qual_t *qual)
642 {
643 	struct sdtemp_softc *sc = device_private(dev);
644 	int error;
645 	uint16_t config;
646 
647 	error = iic_acquire_bus(sc->sc_tag, 0);
648 	if (error != 0)
649 		return false;
650 
651 	error = sdtemp_read_16(sc, SDTEMP_REG_CONFIG, &config);
652 	if (error == 0) {
653 		config &= ~SDTEMP_CONFIG_SHUTDOWN_MODE;
654 		error = sdtemp_write_16(sc, SDTEMP_REG_CONFIG, config);
655 	}
656 	iic_release_bus(sc->sc_tag, 0);
657 	return (error == 0);
658 }
659 
660 /* Device dependent config functions */
661 
662 static void
663 sdtemp_config_mcp(struct sdtemp_softc *sc)
664 {
665 	int rv;
666 	uint8_t resolreg;
667 
668 	/* Note that MCP9805 has no resolution register */
669 	switch (sc->sc_devid_masked) {
670 	case MCP_9804_DEVICE_ID:
671 	case MCP_98242_DEVICE_ID:
672 	case MCP_98243_DEVICE_ID:
673 		resolreg = SDTEMP_REG_MCP_RESOLUTION_9804;
674 		break;
675 	case MCP_98244_DEVICE_ID:
676 		resolreg = SDTEMP_REG_MCP_RESOLUTION_98244;
677 		break;
678 	default:
679 		aprint_error("%s: %s: unknown device ID (%04hx)\n",
680 		    device_xname(sc->sc_dev), __func__, sc->sc_devid_masked);
681 		return;
682 	}
683 
684 	/*
685 	 * Set resolution to the max.
686 	 *
687 	 * Even if it fails, the resolution will be the default. It's not a
688 	 * fatal error.
689 	 */
690 	rv = sdtemp_write_16(sc, resolreg, SDTEMP_CAP_RESOLUTION_MAX);
691 	if (rv == 0)
692 		sc->sc_resolution = SDTEMP_CAP_RESOLUTION_MAX;
693 	else
694 		aprint_error("%s: error %d writing resolution register\n",
695 		    device_xname(sc->sc_dev), rv);
696 }
697 
698 static void
699 sdtemp_config_idt(struct sdtemp_softc *sc)
700 {
701 	int rv;
702 
703 	/*
704 	 * Set resolution to the max.
705 	 *
706 	 * Even if it fails, the resolution will be the default. It's not a
707 	 * fatal error.
708 	 */
709 	rv = sdtemp_write_16(sc, SDTEMP_REG_IDT_RESOLUTION,
710 	    __SHIFTIN(SDTEMP_CAP_RESOLUTION_MAX, SDTEMP_CAP_RESOLUTION));
711 	if (rv == 0)
712 		sc->sc_resolution = SDTEMP_CAP_RESOLUTION_MAX;
713 	else
714 		aprint_error("%s: error %d writing resolution register\n",
715 		    device_xname(sc->sc_dev), rv);
716 }
717 
718 MODULE(MODULE_CLASS_DRIVER, sdtemp, "i2cexec,sysmon_envsys");
719 
720 #ifdef _MODULE
721 #include "ioconf.c"
722 #endif
723 
724 static int
725 sdtemp_modcmd(modcmd_t cmd, void *opaque)
726 {
727 	int error = 0;
728 
729 	switch (cmd) {
730 	case MODULE_CMD_INIT:
731 #ifdef _MODULE
732 		error = config_init_component(cfdriver_ioconf_sdtemp,
733 		    cfattach_ioconf_sdtemp, cfdata_ioconf_sdtemp);
734 #endif
735 		return error;
736 	case MODULE_CMD_FINI:
737 #ifdef _MODULE
738 		error = config_fini_component(cfdriver_ioconf_sdtemp,
739 		    cfattach_ioconf_sdtemp, cfdata_ioconf_sdtemp);
740 #endif
741 		return error;
742 	default:
743 		return ENOTTY;
744 	}
745 }
746