freebsd-nq/sys/dev/iicbus/ds1775.c
Andreas Tobler aa7e99afbd - Improve error handling.
- Add a retry loop for the i2c sensor reading.
- Update the sensor handling for sensors which do not have a location
entry. [1]

Submitted by: [1] Justin Hibbits.
Approved by:	nwhitehorn (mentor)
2011-06-03 18:58:32 +00:00

273 lines
6.7 KiB
C

/*-
* Copyright (c) 2010 Andreas Tobler
* All rights reserved.
*
* 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 AUTHOR ``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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/callout.h>
#include <sys/conf.h>
#include <sys/cpu.h>
#include <sys/ctype.h>
#include <sys/kernel.h>
#include <sys/reboot.h>
#include <sys/rman.h>
#include <sys/sysctl.h>
#include <sys/limits.h>
#include <machine/bus.h>
#include <machine/md_var.h>
#include <dev/iicbus/iicbus.h>
#include <dev/iicbus/iiconf.h>
#include <dev/ofw/openfirm.h>
#include <dev/ofw/ofw_bus.h>
#include <powerpc/powermac/powermac_thermal.h>
#define FCU_ZERO_C_TO_K 2732
/* Drivebay sensor: LM75/DS1775. */
#define DS1775_TEMP 0x0
/* Regular bus attachment functions */
static int ds1775_probe(device_t);
static int ds1775_attach(device_t);
struct ds1775_softc {
struct pmac_therm sc_sensor;
device_t sc_dev;
struct intr_config_hook enum_hook;
uint32_t sc_addr;
};
/* Utility functions */
static int ds1775_sensor_read(struct ds1775_softc *sc);
static int ds1775_sensor_sysctl(SYSCTL_HANDLER_ARGS);
static void ds1775_start(void *xdev);
static int ds1775_read_2(device_t dev, uint32_t addr, uint8_t reg,
uint16_t *data);
static device_method_t ds1775_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, ds1775_probe),
DEVMETHOD(device_attach, ds1775_attach),
{ 0, 0 },
};
static driver_t ds1775_driver = {
"ds1775",
ds1775_methods,
sizeof(struct ds1775_softc)
};
static devclass_t ds1775_devclass;
DRIVER_MODULE(ds1755, iicbus, ds1775_driver, ds1775_devclass, 0, 0);
static int
ds1775_read_2(device_t dev, uint32_t addr, uint8_t reg, uint16_t *data)
{
uint8_t buf[4];
int err, try = 0;
struct iic_msg msg[2] = {
{ addr, IIC_M_WR | IIC_M_NOSTOP, 1, &reg },
{ addr, IIC_M_RD, 2, buf },
};
for (;;)
{
err = iicbus_transfer(dev, msg, 2);
if (err != 0)
goto retry;
*data = *((uint16_t*)buf);
return (0);
retry:
if (++try > 5) {
device_printf(dev, "iicbus read failed\n");
return (-1);
}
pause("ds1775_read_2", hz);
}
}
static int
ds1775_probe(device_t dev)
{
const char *name, *compatible;
struct ds1775_softc *sc;
name = ofw_bus_get_name(dev);
compatible = ofw_bus_get_compat(dev);
if (!name)
return (ENXIO);
if (strcmp(name, "temp-monitor") != 0 ||
(strcmp(compatible, "ds1775") != 0 &&
strcmp(compatible, "lm75") != 0))
return (ENXIO);
sc = device_get_softc(dev);
sc->sc_dev = dev;
sc->sc_addr = iicbus_get_addr(dev);
device_set_desc(dev, "Temp-Monitor DS1775");
return (0);
}
static int
ds1775_attach(device_t dev)
{
struct ds1775_softc *sc;
sc = device_get_softc(dev);
sc->enum_hook.ich_func = ds1775_start;
sc->enum_hook.ich_arg = dev;
/* We have to wait until interrupts are enabled. I2C read and write
* only works if the interrupts are available.
* The unin/i2c is controlled by the htpic on unin. But this is not
* the master. The openpic on mac-io is controlling the htpic.
* This one gets attached after the mac-io probing and then the
* interrupts will be available.
*/
if (config_intrhook_establish(&sc->enum_hook) != 0)
return (ENOMEM);
return (0);
}
static void
ds1775_start(void *xdev)
{
phandle_t child;
struct ds1775_softc *sc;
struct sysctl_oid *sensroot_oid;
struct sysctl_ctx_list *ctx;
ssize_t plen;
int i;
char sysctl_name[40], sysctl_desc[40];
const char *units;
device_t dev = (device_t)xdev;
sc = device_get_softc(dev);
child = ofw_bus_get_node(dev);
ctx = device_get_sysctl_ctx(dev);
sensroot_oid = device_get_sysctl_tree(dev);
if (OF_getprop(child, "hwsensor-zone", &sc->sc_sensor.zone,
sizeof(int)) < 0)
sc->sc_sensor.zone = 0;
plen = OF_getprop(child, "hwsensor-location", sc->sc_sensor.name,
sizeof(sc->sc_sensor.name));
units = "C";
if (plen == -1) {
strcpy(sysctl_name, "sensor");
} else {
for (i = 0; i < strlen(sc->sc_sensor.name); i++) {
sysctl_name[i] = tolower(sc->sc_sensor.name[i]);
if (isspace(sysctl_name[i]))
sysctl_name[i] = '_';
}
sysctl_name[i] = 0;
}
/* Make up target temperatures. These are low, for the drive bay. */
if (sc->sc_sensor.zone == 0) {
sc->sc_sensor.target_temp = 500 + FCU_ZERO_C_TO_K;
sc->sc_sensor.max_temp = 600 + FCU_ZERO_C_TO_K;
}
else {
sc->sc_sensor.target_temp = 300 + FCU_ZERO_C_TO_K;
sc->sc_sensor.max_temp = 600 + FCU_ZERO_C_TO_K;
}
sc->sc_sensor.read =
(int (*)(struct pmac_therm *sc))(ds1775_sensor_read);
pmac_thermal_sensor_register(&sc->sc_sensor);
sprintf(sysctl_desc,"%s (%s)", sc->sc_sensor.name, units);
SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(sensroot_oid), OID_AUTO,
sysctl_name,
CTLTYPE_INT | CTLFLAG_RD | CTLFLAG_MPSAFE, dev,
0, ds1775_sensor_sysctl, "IK", sysctl_desc);
config_intrhook_disestablish(&sc->enum_hook);
}
static int
ds1775_sensor_read(struct ds1775_softc *sc)
{
uint16_t buf[2];
uint16_t read;
int err;
err = ds1775_read_2(sc->sc_dev, sc->sc_addr, DS1775_TEMP, buf);
if (err < 0)
return (-1);
read = *((int16_t *)buf);
/* The default mode of the ADC is 9 bit, the resolution is 0.5 C per
bit. The temperature is in tenth kelvin.
*/
return (((int16_t)(read) >> 7) * 5 + FCU_ZERO_C_TO_K);
}
static int
ds1775_sensor_sysctl(SYSCTL_HANDLER_ARGS)
{
device_t dev;
struct ds1775_softc *sc;
int error;
unsigned int temp;
dev = arg1;
sc = device_get_softc(dev);
temp = ds1775_sensor_read(sc);
if (temp < 0)
return (EIO);
error = sysctl_handle_int(oidp, &temp, 0, req);
return (error);
}