powerpc/windfarm: Add ad7417 sensor
For user by the upcoming windfarm_pm72 and windfarm_rm31 Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Benjamin Herrenschmidt
parent
33e6820b76
commit
850dc32168
1 changed files with 347 additions and 0 deletions
347
drivers/macintosh/windfarm_ad7417_sensor.c
Normal file
347
drivers/macintosh/windfarm_ad7417_sensor.c
Normal file
|
|
@ -0,0 +1,347 @@
|
|||
/*
|
||||
* Windfarm PowerMac thermal control. AD7417 sensors
|
||||
*
|
||||
* Copyright 2012 Benjamin Herrenschmidt, IBM Corp.
|
||||
*
|
||||
* Released under the term of the GNU GPL v2.
|
||||
*/
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/errno.h>
|
||||
#include <linux/kernel.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/wait.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <asm/prom.h>
|
||||
#include <asm/machdep.h>
|
||||
#include <asm/io.h>
|
||||
#include <asm/sections.h>
|
||||
|
||||
#include "windfarm.h"
|
||||
#include "windfarm_mpu.h"
|
||||
|
||||
#define VERSION "1.0"
|
||||
|
||||
struct wf_ad7417_priv {
|
||||
struct kref ref;
|
||||
struct i2c_client *i2c;
|
||||
u8 config;
|
||||
u8 cpu;
|
||||
const struct mpu_data *mpu;
|
||||
struct wf_sensor sensors[5];
|
||||
struct mutex lock;
|
||||
};
|
||||
|
||||
static int wf_ad7417_temp_get(struct wf_sensor *sr, s32 *value)
|
||||
{
|
||||
struct wf_ad7417_priv *pv = sr->priv;
|
||||
u8 buf[2];
|
||||
s16 raw;
|
||||
int rc;
|
||||
|
||||
*value = 0;
|
||||
mutex_lock(&pv->lock);
|
||||
|
||||
/* Read temp register */
|
||||
buf[0] = 0;
|
||||
rc = i2c_master_send(pv->i2c, buf, 1);
|
||||
if (rc < 0)
|
||||
goto error;
|
||||
rc = i2c_master_recv(pv->i2c, buf, 2);
|
||||
if (rc < 0)
|
||||
goto error;
|
||||
|
||||
/* Read a a 16-bit signed value */
|
||||
raw = be16_to_cpup((__le16 *)buf);
|
||||
|
||||
/* Convert 8.8-bit to 16.16 fixed point */
|
||||
*value = ((s32)raw) << 8;
|
||||
|
||||
mutex_unlock(&pv->lock);
|
||||
return 0;
|
||||
|
||||
error:
|
||||
mutex_unlock(&pv->lock);
|
||||
return -1;
|
||||
}
|
||||
|
||||
/*
|
||||
* Scaling factors for the AD7417 ADC converters (except
|
||||
* for the CPU diode which is obtained from the EEPROM).
|
||||
* Those values are obtained from the property list of
|
||||
* the darwin driver
|
||||
*/
|
||||
#define ADC_12V_CURRENT_SCALE 0x0320 /* _AD2 */
|
||||
#define ADC_CPU_VOLTAGE_SCALE 0x00a0 /* _AD3 */
|
||||
#define ADC_CPU_CURRENT_SCALE 0x1f40 /* _AD4 */
|
||||
|
||||
static void wf_ad7417_adc_convert(struct wf_ad7417_priv *pv,
|
||||
int chan, s32 raw, s32 *value)
|
||||
{
|
||||
switch(chan) {
|
||||
case 1: /* Diode */
|
||||
*value = (raw * (s32)pv->mpu->mdiode +
|
||||
((s32)pv->mpu->bdiode << 12)) >> 2;
|
||||
break;
|
||||
case 2: /* 12v current */
|
||||
*value = raw * ADC_12V_CURRENT_SCALE;
|
||||
break;
|
||||
case 3: /* core voltage */
|
||||
*value = raw * ADC_CPU_VOLTAGE_SCALE;
|
||||
break;
|
||||
case 4: /* core current */
|
||||
*value = raw * ADC_CPU_CURRENT_SCALE;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
static int wf_ad7417_adc_get(struct wf_sensor *sr, s32 *value)
|
||||
{
|
||||
struct wf_ad7417_priv *pv = sr->priv;
|
||||
int chan = sr - pv->sensors;
|
||||
int i, rc;
|
||||
u8 buf[2];
|
||||
u16 raw;
|
||||
|
||||
*value = 0;
|
||||
mutex_lock(&pv->lock);
|
||||
for (i = 0; i < 10; i++) {
|
||||
/* Set channel */
|
||||
buf[0] = 1;
|
||||
buf[1] = (pv->config & 0x1f) | (chan << 5);
|
||||
rc = i2c_master_send(pv->i2c, buf, 2);
|
||||
if (rc < 0)
|
||||
goto error;
|
||||
|
||||
/* Wait for conversion */
|
||||
msleep(1);
|
||||
|
||||
/* Switch to data register */
|
||||
buf[0] = 4;
|
||||
rc = i2c_master_send(pv->i2c, buf, 1);
|
||||
if (rc < 0)
|
||||
goto error;
|
||||
|
||||
/* Read result */
|
||||
rc = i2c_master_recv(pv->i2c, buf, 2);
|
||||
if (rc < 0)
|
||||
goto error;
|
||||
|
||||
/* Read a a 16-bit signed value */
|
||||
raw = be16_to_cpup((__le16 *)buf) >> 6;
|
||||
wf_ad7417_adc_convert(pv, chan, raw, value);
|
||||
|
||||
dev_vdbg(&pv->i2c->dev, "ADC chan %d [%s]"
|
||||
" raw value: 0x%x, conv to: 0x%08x\n",
|
||||
chan, sr->name, raw, *value);
|
||||
|
||||
mutex_unlock(&pv->lock);
|
||||
return 0;
|
||||
|
||||
error:
|
||||
dev_dbg(&pv->i2c->dev,
|
||||
"Error reading ADC, try %d...\n", i);
|
||||
if (i < 9)
|
||||
msleep(10);
|
||||
}
|
||||
mutex_unlock(&pv->lock);
|
||||
return -1;
|
||||
}
|
||||
|
||||
static void wf_ad7417_release(struct kref *ref)
|
||||
{
|
||||
struct wf_ad7417_priv *pv = container_of(ref,
|
||||
struct wf_ad7417_priv, ref);
|
||||
kfree(pv);
|
||||
}
|
||||
|
||||
static void wf_ad7417_sensor_release(struct wf_sensor *sr)
|
||||
{
|
||||
struct wf_ad7417_priv *pv = sr->priv;
|
||||
|
||||
kfree(sr->name);
|
||||
kref_put(&pv->ref, wf_ad7417_release);
|
||||
}
|
||||
|
||||
static const struct wf_sensor_ops wf_ad7417_temp_ops = {
|
||||
.get_value = wf_ad7417_temp_get,
|
||||
.release = wf_ad7417_sensor_release,
|
||||
.owner = THIS_MODULE,
|
||||
};
|
||||
|
||||
static const struct wf_sensor_ops wf_ad7417_adc_ops = {
|
||||
.get_value = wf_ad7417_adc_get,
|
||||
.release = wf_ad7417_sensor_release,
|
||||
.owner = THIS_MODULE,
|
||||
};
|
||||
|
||||
static void __devinit wf_ad7417_add_sensor(struct wf_ad7417_priv *pv,
|
||||
int index, const char *name,
|
||||
const struct wf_sensor_ops *ops)
|
||||
{
|
||||
pv->sensors[index].name = kasprintf(GFP_KERNEL, "%s-%d", name, pv->cpu);
|
||||
pv->sensors[index].priv = pv;
|
||||
pv->sensors[index].ops = ops;
|
||||
if (!wf_register_sensor(&pv->sensors[index]))
|
||||
kref_get(&pv->ref);
|
||||
}
|
||||
|
||||
static void __devinit wf_ad7417_init_chip(struct wf_ad7417_priv *pv)
|
||||
{
|
||||
int rc;
|
||||
u8 buf[2];
|
||||
u8 config = 0;
|
||||
|
||||
/*
|
||||
* Read ADC the configuration register and cache it. We
|
||||
* also make sure Config2 contains proper values, I've seen
|
||||
* cases where we got stale grabage in there, thus preventing
|
||||
* proper reading of conv. values
|
||||
*/
|
||||
|
||||
/* Clear Config2 */
|
||||
buf[0] = 5;
|
||||
buf[1] = 0;
|
||||
i2c_master_send(pv->i2c, buf, 2);
|
||||
|
||||
/* Read & cache Config1 */
|
||||
buf[0] = 1;
|
||||
rc = i2c_master_send(pv->i2c, buf, 1);
|
||||
if (rc > 0) {
|
||||
rc = i2c_master_recv(pv->i2c, buf, 1);
|
||||
if (rc > 0) {
|
||||
config = buf[0];
|
||||
|
||||
dev_dbg(&pv->i2c->dev, "ADC config reg: %02x\n",
|
||||
config);
|
||||
|
||||
/* Disable shutdown mode */
|
||||
config &= 0xfe;
|
||||
buf[0] = 1;
|
||||
buf[1] = config;
|
||||
rc = i2c_master_send(pv->i2c, buf, 2);
|
||||
}
|
||||
}
|
||||
if (rc <= 0)
|
||||
dev_err(&pv->i2c->dev, "Error reading ADC config\n");
|
||||
|
||||
pv->config = config;
|
||||
}
|
||||
|
||||
static int __devinit wf_ad7417_probe(struct i2c_client *client,
|
||||
const struct i2c_device_id *id)
|
||||
{
|
||||
struct wf_ad7417_priv *pv;
|
||||
const struct mpu_data *mpu;
|
||||
const char *loc;
|
||||
int cpu_nr;
|
||||
|
||||
loc = of_get_property(client->dev.of_node, "hwsensor-location", NULL);
|
||||
if (!loc) {
|
||||
dev_warn(&client->dev, "Missing hwsensor-location property!\n");
|
||||
return -ENXIO;
|
||||
}
|
||||
|
||||
/*
|
||||
* Identify which CPU we belong to by looking at the first entry
|
||||
* in the hwsensor-location list
|
||||
*/
|
||||
if (!strncmp(loc, "CPU A", 5))
|
||||
cpu_nr = 0;
|
||||
else if (!strncmp(loc, "CPU B", 5))
|
||||
cpu_nr = 1;
|
||||
else {
|
||||
pr_err("wf_ad7417: Can't identify location %s\n", loc);
|
||||
return -ENXIO;
|
||||
}
|
||||
mpu = wf_get_mpu(cpu_nr);
|
||||
if (!mpu) {
|
||||
dev_err(&client->dev, "Failed to retrieve MPU data\n");
|
||||
return -ENXIO;
|
||||
}
|
||||
|
||||
pv = kzalloc(sizeof(struct wf_ad7417_priv), GFP_KERNEL);
|
||||
if (pv == NULL)
|
||||
return -ENODEV;
|
||||
|
||||
kref_init(&pv->ref);
|
||||
mutex_init(&pv->lock);
|
||||
pv->i2c = client;
|
||||
pv->cpu = cpu_nr;
|
||||
pv->mpu = mpu;
|
||||
dev_set_drvdata(&client->dev, pv);
|
||||
|
||||
/* Initialize the chip */
|
||||
wf_ad7417_init_chip(pv);
|
||||
|
||||
/*
|
||||
* We cannot rely on Apple device-tree giving us child
|
||||
* node with the names of the individual sensors so we
|
||||
* just hard code what we know about them
|
||||
*/
|
||||
wf_ad7417_add_sensor(pv, 0, "cpu-amb-temp", &wf_ad7417_temp_ops);
|
||||
wf_ad7417_add_sensor(pv, 1, "cpu-diode-temp", &wf_ad7417_adc_ops);
|
||||
wf_ad7417_add_sensor(pv, 2, "cpu-12v-current", &wf_ad7417_adc_ops);
|
||||
wf_ad7417_add_sensor(pv, 3, "cpu-voltage", &wf_ad7417_adc_ops);
|
||||
wf_ad7417_add_sensor(pv, 4, "cpu-current", &wf_ad7417_adc_ops);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int __devexit wf_ad7417_remove(struct i2c_client *client)
|
||||
{
|
||||
struct wf_ad7417_priv *pv = dev_get_drvdata(&client->dev);
|
||||
int i;
|
||||
|
||||
/* Mark client detached */
|
||||
pv->i2c = NULL;
|
||||
|
||||
/* Release sensor */
|
||||
for (i = 0; i < 5; i++)
|
||||
wf_unregister_sensor(&pv->sensors[i]);
|
||||
|
||||
kref_put(&pv->ref, wf_ad7417_release);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct i2c_device_id wf_ad7417_id[] = {
|
||||
{ "MAC,ad7417", 0 },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, wf_ad7417_id);
|
||||
|
||||
static struct i2c_driver wf_ad7417_driver = {
|
||||
.driver = {
|
||||
.name = "wf_ad7417",
|
||||
},
|
||||
.probe = wf_ad7417_probe,
|
||||
.remove = wf_ad7417_remove,
|
||||
.id_table = wf_ad7417_id,
|
||||
};
|
||||
|
||||
static int __devinit wf_ad7417_init(void)
|
||||
{
|
||||
/* This is only supported on these machines */
|
||||
if (!of_machine_is_compatible("PowerMac7,2") &&
|
||||
!of_machine_is_compatible("PowerMac7,3") &&
|
||||
!of_machine_is_compatible("RackMac3,1"))
|
||||
return -ENODEV;
|
||||
|
||||
return i2c_add_driver(&wf_ad7417_driver);
|
||||
}
|
||||
|
||||
static void __devexit wf_ad7417_exit(void)
|
||||
{
|
||||
i2c_del_driver(&wf_ad7417_driver);
|
||||
}
|
||||
|
||||
module_init(wf_ad7417_init);
|
||||
module_exit(wf_ad7417_exit);
|
||||
|
||||
MODULE_AUTHOR("Benjamin Herrenschmidt <benh@kernel.crashing.org>");
|
||||
MODULE_DESCRIPTION("ad7417 sensor driver for PowerMacs");
|
||||
MODULE_LICENSE("GPL");
|
||||
|
||||
Loading…
Reference in a new issue