/* $NetBSD: mcp980x.c,v 1.6 2018/06/16 21:22:13 thorpej Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Radoslaw Kujawa.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Microchip MCP9800/1/2/3 2-Wire High-Accuracy Temperature Sensor driver.
*
* TODO: better error checking, particurarly in user settable limits.
*
* Note: MCP9805 is different and is supported by the sdtemp(4) driver.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: mcp980x.c,v 1.6 2018/06/16 21:22:13 thorpej Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/mutex.h>
#include <sys/endian.h>
#include <sys/sysctl.h>
#include <sys/bus.h>
#include <dev/i2c/i2cvar.h>
#include <dev/sysmon/sysmonvar.h>
#include <dev/i2c/mcp980xreg.h>
struct mcp980x_softc {
device_t sc_dev;
i2c_tag_t sc_tag;
i2c_addr_t sc_addr;
int sc_res;
int sc_hyst;
int sc_limit;
/* envsys(4) stuff */
struct sysmon_envsys *sc_sme;
envsys_data_t sc_sensor;
kmutex_t sc_lock;
};
static int mcp980x_match(device_t, cfdata_t, void *);
static void mcp980x_attach(device_t, device_t, void *);
static uint8_t mcp980x_reg_read_1(struct mcp980x_softc *, uint8_t);
static uint16_t mcp980x_reg_read_2(struct mcp980x_softc *, uint8_t);
static void mcp980x_reg_write_1(struct mcp980x_softc *, uint8_t, uint8_t);
static uint8_t mcp980x_resolution_get(struct mcp980x_softc *);
static void mcp980x_resolution_set(struct mcp980x_softc *, uint8_t);
static int8_t mcp980x_hysteresis_get(struct mcp980x_softc *);
static void mcp980x_hysteresis_set(struct mcp980x_softc *, int8_t);
static int8_t mcp980x_templimit_get(struct mcp980x_softc *);
static void mcp980x_templimit_set(struct mcp980x_softc *, int8_t);
static int8_t mcp980x_s8b_get(struct mcp980x_softc *, uint8_t);
static void mcp980x_s8b_set(struct mcp980x_softc *, uint8_t, int8_t);
static uint32_t mcp980x_temperature(struct mcp980x_softc *);
static void mcp980x_envsys_register(struct mcp980x_softc *);
static void mcp980x_envsys_refresh(struct sysmon_envsys *, envsys_data_t *);
static void mcp980x_setup_sysctl(struct mcp980x_softc *);
static int sysctl_mcp980x_res(SYSCTLFN_ARGS);
static int sysctl_mcp980x_hysteresis(SYSCTLFN_ARGS);
static int sysctl_mcp980x_templimit(SYSCTLFN_ARGS);
CFATTACH_DECL_NEW(mcp980x, sizeof (struct mcp980x_softc),
mcp980x_match, mcp980x_attach, NULL, NULL);
static int
mcp980x_match(device_t parent, cfdata_t cf, void *aux)
{
if (ia->ia_addr >= MCP980X_ADDR_CONST &&
ia->ia_addr <= (MCP980X_ADDR_CONST + MCP980X_ADDR_VAR))
return I2C_MATCH_ADDRESS_ONLY;
return 0;
}
static void
mcp980x_attach(device_t parent, device_t self, void *aux)
{
struct mcp980x_softc *sc = device_private(self);
struct i2c_attach_args *ia = aux;
sc->sc_dev = self;
sc->sc_addr = ia->ia_addr;
sc->sc_tag = ia->ia_tag;
aprint_normal(": Microchip MCP980x Temperature Sensor\n");
sc->sc_res = MCP980X_CONFIG_ADC_RES_12BIT;
mcp980x_resolution_set(sc, sc->sc_res);
sc->sc_hyst = mcp980x_hysteresis_get(sc);
sc->sc_limit = mcp980x_templimit_get(sc);
mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
mcp980x_setup_sysctl(sc);
mcp980x_envsys_register(sc);
}
static uint16_t
mcp980x_reg_read_2(struct mcp980x_softc *sc, uint8_t reg)
{
uint16_t rv;
if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
aprint_error_dev(sc->sc_dev, "cannot acquire bus for read\n");
return 0;
}
if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, ®,
1, &rv, 2, I2C_F_POLL)) {
aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return 0;
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return be16toh(rv);
}
static uint8_t
mcp980x_reg_read_1(struct mcp980x_softc *sc, uint8_t reg)
{
uint8_t rv;
if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
aprint_error_dev(sc->sc_dev, "cannot acquire bus for read\n");
return 0;
}
if (iic_exec(sc->sc_tag, I2C_OP_READ_WITH_STOP, sc->sc_addr, ®,
1, &rv, 1, I2C_F_POLL)) {
aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return 0;
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
return rv;
}
static void
mcp980x_reg_write_2(struct mcp980x_softc *sc, uint8_t reg, uint16_t val)
{
uint16_t beval;
beval = htobe16(val);
if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
aprint_error_dev(sc->sc_dev, "cannot acquire bus for write\n");
return;
}
if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, ®,
1, &beval, 2, I2C_F_POLL)) {
aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
}
static void
mcp980x_reg_write_1(struct mcp980x_softc *sc, uint8_t reg, uint8_t val)
{
if (iic_acquire_bus(sc->sc_tag, I2C_F_POLL) != 0) {
aprint_error_dev(sc->sc_dev, "cannot acquire bus for write\n");
return;
}
if (iic_exec(sc->sc_tag, I2C_OP_WRITE_WITH_STOP, sc->sc_addr, ®,
1, &val, 1, I2C_F_POLL)) {
aprint_error_dev(sc->sc_dev, "cannot execute operation\n");
}
iic_release_bus(sc->sc_tag, I2C_F_POLL);
}
static int8_t
mcp980x_templimit_get(struct mcp980x_softc *sc)
{
return mcp980x_s8b_get(sc, MCP980X_TEMP_LIMIT);
}
static void
mcp980x_templimit_set(struct mcp980x_softc *sc, int8_t val)
{
mcp980x_s8b_set(sc, MCP980X_TEMP_LIMIT, val);
}
static int8_t
mcp980x_hysteresis_get(struct mcp980x_softc *sc)
{
return mcp980x_s8b_get(sc, MCP980X_TEMP_HYSTERESIS);
}
static void
mcp980x_hysteresis_set(struct mcp980x_softc *sc, int8_t val)
{
mcp980x_s8b_set(sc, MCP980X_TEMP_HYSTERESIS, val);
}
static int8_t
mcp980x_s8b_get(struct mcp980x_softc *sc, uint8_t reg)
{
return mcp980x_reg_read_2(sc, reg) >> MCP980X_TEMP_HYSTLIMIT_INT_SHIFT;
}
static void
mcp980x_s8b_set(struct mcp980x_softc *sc, uint8_t reg, int8_t val)
{
mcp980x_reg_write_2(sc, reg, val << MCP980X_TEMP_HYSTLIMIT_INT_SHIFT);
}
static uint8_t
mcp980x_resolution_get(struct mcp980x_softc *sc)
{
uint8_t cfg, res;
cfg = mcp980x_reg_read_1(sc, MCP980X_CONFIG);
res = (cfg & MCP980X_CONFIG_ADC_RES) >>
MCP980X_CONFIG_ADC_RES_SHIFT;
return res;
}
static void
mcp980x_resolution_set(struct mcp980x_softc *sc, uint8_t res)
{
uint8_t cfg;
/* read config register but discard resolution bits */
cfg = mcp980x_reg_read_1(sc, MCP980X_CONFIG) & ~MCP980X_CONFIG_ADC_RES;
/* set resolution bits to new value */
cfg |= res << MCP980X_CONFIG_ADC_RES_SHIFT;
mcp980x_reg_write_1(sc, MCP980X_CONFIG, cfg);
}
/* Get temperature in microKelvins. */
static uint32_t
mcp980x_temperature(struct mcp980x_softc *sc)
{
uint16_t raw;
uint32_t rv, uk, basedegc;
raw = mcp980x_reg_read_2(sc, MCP980X_AMBIENT_TEMP);
basedegc = (raw & MCP980X_AMBIENT_TEMP_DEGREES) >>
MCP980X_AMBIENT_TEMP_DEGREES_SHIFT;
uk = 1000000 * basedegc;
if (raw & MCP980X_AMBIENT_TEMP_05DEGREE)
uk += 500000;
if (raw & MCP980X_AMBIENT_TEMP_025DEGREE)
uk += 250000;
if (raw & MCP980X_AMBIENT_TEMP_0125DEGREE)
uk += 125000;
if (raw & MCP980X_AMBIENT_TEMP_00625DEGREE)
uk += 62500;
if (raw & MCP980X_AMBIENT_TEMP_SIGN)
rv = 273150000U - uk;
else
rv = 273150000U + uk;
return rv;
}
static void
mcp980x_envsys_register(struct mcp980x_softc *sc)
{
sc->sc_sme = sysmon_envsys_create();
strlcpy(sc->sc_sensor.desc, "Ambient temp",
sizeof(sc->sc_sensor.desc));
sc->sc_sensor.units = ENVSYS_STEMP;
sc->sc_sensor.state = ENVSYS_SINVALID;
if (sysmon_envsys_sensor_attach(sc->sc_sme, &sc->sc_sensor)) {
aprint_error_dev(sc->sc_dev,
"error attaching sensor\n");
return;
}
sc->sc_sme->sme_name = device_xname(sc->sc_dev);
sc->sc_sme->sme_cookie = sc;
sc->sc_sme->sme_refresh = mcp980x_envsys_refresh;
if (sysmon_envsys_register(sc->sc_sme)) {
aprint_error_dev(sc->sc_dev, "unable to register in sysmon\n");
sysmon_envsys_destroy(sc->sc_sme);
}
}
static void
mcp980x_envsys_refresh(struct sysmon_envsys *sme, envsys_data_t *edata)
{
struct mcp980x_softc *sc = sme->sme_cookie;
mutex_enter(&sc->sc_lock);
edata->value_cur = mcp980x_temperature(sc);
edata->state = ENVSYS_SVALID;
mutex_exit(&sc->sc_lock);
}
static void
mcp980x_setup_sysctl(struct mcp980x_softc *sc)
{
const struct sysctlnode *me = NULL, *node = NULL;
sysctl_createv(NULL, 0, NULL, &me,
CTLFLAG_READWRITE,
CTLTYPE_NODE, device_xname(sc->sc_dev), NULL,
NULL, 0, NULL, 0,
CTL_MACHDEP, CTL_CREATE, CTL_EOL);
sysctl_createv(NULL, 0, NULL, &node,
CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
CTLTYPE_INT, "res", "Resolution",
sysctl_mcp980x_res, 1, (void *)sc, 0,
CTL_MACHDEP, me->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(NULL, 0, NULL, &node,
CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
CTLTYPE_INT, "hysteresis", "Temperature hysteresis",
sysctl_mcp980x_hysteresis, 1, (void *)sc, 0,
CTL_MACHDEP, me->sysctl_num, CTL_CREATE, CTL_EOL);
sysctl_createv(NULL, 0, NULL, &node,
CTLFLAG_READWRITE | CTLFLAG_OWNDESC,
CTLTYPE_INT, "templimit", "Temperature limit",
sysctl_mcp980x_templimit, 1, (void *)sc, 0,
CTL_MACHDEP, me->sysctl_num, CTL_CREATE, CTL_EOL);
}
SYSCTL_SETUP(sysctl_mcp980x_setup, "sysctl mcp980x subtree setup")
{
sysctl_createv(NULL, 0, NULL, NULL, CTLFLAG_PERMANENT,
CTLTYPE_NODE, "machdep", NULL, NULL, 0, NULL, 0,
CTL_MACHDEP, CTL_EOL);
}
static int
sysctl_mcp980x_res(SYSCTLFN_ARGS)
{
struct sysctlnode node = *rnode;
struct mcp980x_softc *sc = node.sysctl_data;
int newres, err;
node.sysctl_data = &sc->sc_res;
if ((err = (sysctl_lookup(SYSCTLFN_CALL(&node)))) != 0)
return err;
if (newp) {
newres = *(int *)node.sysctl_data;
if (newres > MCP980X_CONFIG_ADC_RES_12BIT)
return EINVAL;
sc->sc_res = (uint8_t) newres;
mcp980x_resolution_set(sc, sc->sc_res);
return 0;
} else {
sc->sc_res = mcp980x_resolution_get(sc);
node.sysctl_size = 4;
}
return err;
}
static int
sysctl_mcp980x_hysteresis(SYSCTLFN_ARGS)
{
struct sysctlnode node = *rnode;
struct mcp980x_softc *sc = node.sysctl_data;
int newhyst, err;
node.sysctl_data = &sc->sc_hyst;
if ((err = (sysctl_lookup(SYSCTLFN_CALL(&node)))) != 0)
return err;
if (newp) {
newhyst = *(int *)node.sysctl_data;
sc->sc_hyst = newhyst;
mcp980x_hysteresis_set(sc, sc->sc_hyst);
return 0;
} else {
sc->sc_hyst = mcp980x_hysteresis_get(sc);
node.sysctl_size = 4;
}
return err;
}
static int
sysctl_mcp980x_templimit(SYSCTLFN_ARGS)
{
struct sysctlnode node = *rnode;
struct mcp980x_softc *sc = node.sysctl_data;
int newlimit, err;
node.sysctl_data = &sc->sc_limit;
if ((err = (sysctl_lookup(SYSCTLFN_CALL(&node)))) != 0)
return err;
if (newp) {
newlimit = *(int *)node.sysctl_data;
sc->sc_limit = newlimit;
mcp980x_templimit_set(sc, sc->sc_limit);
return 0;
} else {
sc->sc_limit = mcp980x_templimit_get(sc);
node.sysctl_size = 4;
}
return err;
}