alistair23-linux/drivers/macintosh/windfarm_max6690_sensor.c
Benjamin Herrenschmidt d839ba2ab2 powerpc/windfarm: Updates to lm75 and max6690 sensors
This allows those modules to load on PowerMac7,2 PowerMac7,3
and RackMac3,1 and add the sensor name conversion for those
machines.

This will be used by the corresponding new windfarm modules
for those machines.

Note that since therm_pm72 is linked first, it will still
take priority on those i2c devices if built-in. If using modules
it will depend which is loaded first, but you should avoid building
therm_pm72 if you are using the new windfarm drivers

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-30 15:37:24 +10:00

149 lines
3.3 KiB
C

/*
* Windfarm PowerMac thermal control. MAX6690 sensor.
*
* Copyright (C) 2005 Paul Mackerras, IBM Corp. <paulus@samba.org>
*
* Use and redistribute under the terms of the GNU GPL v2.
*/
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <asm/prom.h>
#include <asm/pmac_low_i2c.h>
#include "windfarm.h"
#define VERSION "1.0"
/* This currently only exports the external temperature sensor,
since that's all the control loops need. */
/* Some MAX6690 register numbers */
#define MAX6690_INTERNAL_TEMP 0
#define MAX6690_EXTERNAL_TEMP 1
struct wf_6690_sensor {
struct i2c_client *i2c;
struct wf_sensor sens;
};
#define wf_to_6690(x) container_of((x), struct wf_6690_sensor, sens)
static int wf_max6690_get(struct wf_sensor *sr, s32 *value)
{
struct wf_6690_sensor *max = wf_to_6690(sr);
s32 data;
if (max->i2c == NULL)
return -ENODEV;
/* chip gets initialized by firmware */
data = i2c_smbus_read_byte_data(max->i2c, MAX6690_EXTERNAL_TEMP);
if (data < 0)
return data;
*value = data << 16;
return 0;
}
static void wf_max6690_release(struct wf_sensor *sr)
{
struct wf_6690_sensor *max = wf_to_6690(sr);
kfree(max);
}
static struct wf_sensor_ops wf_max6690_ops = {
.get_value = wf_max6690_get,
.release = wf_max6690_release,
.owner = THIS_MODULE,
};
static int wf_max6690_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
const char *name, *loc;
struct wf_6690_sensor *max;
int rc;
loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL);
if (!loc) {
dev_warn(&client->dev, "Missing hwsensor-location property!\n");
return -ENXIO;
}
/*
* We only expose the external temperature register for
* now as this is all we need for our control loops
*/
if (!strcmp(loc, "BACKSIDE") || !strcmp(loc, "SYS CTRLR AMBIENT"))
name = "backside-temp";
else if (!strcmp(loc, "NB Ambient"))
name = "north-bridge-temp";
else if (!strcmp(loc, "GPU Ambient"))
name = "gpu-temp";
else
return -ENXIO;
max = kzalloc(sizeof(struct wf_6690_sensor), GFP_KERNEL);
if (max == NULL) {
printk(KERN_ERR "windfarm: Couldn't create MAX6690 sensor: "
"no memory\n");
return -ENOMEM;
}
max->i2c = client;
max->sens.name = (char *)name; /* XXX fix constness in structure */
max->sens.ops = &wf_max6690_ops;
i2c_set_clientdata(client, max);
rc = wf_register_sensor(&max->sens);
if (rc)
kfree(max);
return rc;
}
static int wf_max6690_remove(struct i2c_client *client)
{
struct wf_6690_sensor *max = i2c_get_clientdata(client);
max->i2c = NULL;
wf_unregister_sensor(&max->sens);
return 0;
}
static const struct i2c_device_id wf_max6690_id[] = {
{ "MAC,max6690", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, wf_max6690_id);
static struct i2c_driver wf_max6690_driver = {
.driver = {
.name = "wf_max6690",
},
.probe = wf_max6690_probe,
.remove = wf_max6690_remove,
.id_table = wf_max6690_id,
};
static int __init wf_max6690_sensor_init(void)
{
return i2c_add_driver(&wf_max6690_driver);
}
static void __exit wf_max6690_sensor_exit(void)
{
i2c_del_driver(&wf_max6690_driver);
}
module_init(wf_max6690_sensor_init);
module_exit(wf_max6690_sensor_exit);
MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
MODULE_DESCRIPTION("MAX6690 sensor objects for PowerMac thermal control");
MODULE_LICENSE("GPL");