131 lines
3.8 KiB
C
131 lines
3.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Delta AHE-50DC power shelf fan control module driver
|
|
*
|
|
* Copyright 2021 Zev Weiss <zev@bewilderbeest.net>
|
|
*/
|
|
|
|
#include <linux/i2c.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/pmbus.h>
|
|
|
|
#include "pmbus.h"
|
|
|
|
#define AHE50DC_PMBUS_READ_TEMP4 0xd0
|
|
|
|
static int ahe50dc_fan_write_byte(struct i2c_client *client, int page, u8 value)
|
|
{
|
|
/*
|
|
* The CLEAR_FAULTS operation seems to sometimes (unpredictably, perhaps
|
|
* 5% of the time or so) trigger a problematic phenomenon in which the
|
|
* fan speeds surge momentarily and at least some (perhaps all?) of the
|
|
* system's power outputs experience a glitch.
|
|
*
|
|
* However, according to Delta it should be OK to simply not send any
|
|
* CLEAR_FAULTS commands (the device doesn't seem to be capable of
|
|
* reporting any faults anyway), so just blackhole them unconditionally.
|
|
*/
|
|
return value == PMBUS_CLEAR_FAULTS ? -EOPNOTSUPP : -ENODATA;
|
|
}
|
|
|
|
static int ahe50dc_fan_read_word_data(struct i2c_client *client, int page, int phase, int reg)
|
|
{
|
|
/* temp1 in (virtual) page 1 is remapped to mfr-specific temp4 */
|
|
if (page == 1) {
|
|
if (reg == PMBUS_READ_TEMPERATURE_1)
|
|
return i2c_smbus_read_word_data(client, AHE50DC_PMBUS_READ_TEMP4);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
/*
|
|
* There's a fairly limited set of commands this device actually
|
|
* supports, so here we block attempts to read anything else (which
|
|
* return 0xffff and would cause confusion elsewhere).
|
|
*/
|
|
switch (reg) {
|
|
case PMBUS_STATUS_WORD:
|
|
case PMBUS_FAN_COMMAND_1:
|
|
case PMBUS_FAN_COMMAND_2:
|
|
case PMBUS_FAN_COMMAND_3:
|
|
case PMBUS_FAN_COMMAND_4:
|
|
case PMBUS_STATUS_FAN_12:
|
|
case PMBUS_STATUS_FAN_34:
|
|
case PMBUS_READ_VIN:
|
|
case PMBUS_READ_TEMPERATURE_1:
|
|
case PMBUS_READ_TEMPERATURE_2:
|
|
case PMBUS_READ_TEMPERATURE_3:
|
|
case PMBUS_READ_FAN_SPEED_1:
|
|
case PMBUS_READ_FAN_SPEED_2:
|
|
case PMBUS_READ_FAN_SPEED_3:
|
|
case PMBUS_READ_FAN_SPEED_4:
|
|
return -ENODATA;
|
|
default:
|
|
return -EOPNOTSUPP;
|
|
}
|
|
}
|
|
|
|
static struct pmbus_driver_info ahe50dc_fan_info = {
|
|
.pages = 2,
|
|
.format[PSC_FAN] = direct,
|
|
.format[PSC_TEMPERATURE] = direct,
|
|
.format[PSC_VOLTAGE_IN] = direct,
|
|
.m[PSC_FAN] = 1,
|
|
.b[PSC_FAN] = 0,
|
|
.R[PSC_FAN] = 0,
|
|
.m[PSC_TEMPERATURE] = 1,
|
|
.b[PSC_TEMPERATURE] = 0,
|
|
.R[PSC_TEMPERATURE] = 1,
|
|
.m[PSC_VOLTAGE_IN] = 1,
|
|
.b[PSC_VOLTAGE_IN] = 0,
|
|
.R[PSC_VOLTAGE_IN] = 3,
|
|
.func[0] = PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
|
|
PMBUS_HAVE_VIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_FAN34 |
|
|
PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_STATUS_FAN34 | PMBUS_PAGE_VIRTUAL,
|
|
.func[1] = PMBUS_HAVE_TEMP | PMBUS_PAGE_VIRTUAL,
|
|
.write_byte = ahe50dc_fan_write_byte,
|
|
.read_word_data = ahe50dc_fan_read_word_data,
|
|
};
|
|
|
|
/*
|
|
* CAPABILITY returns 0xff, which appears to be this device's way indicating
|
|
* it doesn't support something (and if we enable I2C_CLIENT_PEC on seeing bit
|
|
* 7 being set it generates bad PECs, so let's not go there).
|
|
*/
|
|
static struct pmbus_platform_data ahe50dc_fan_data = {
|
|
.flags = PMBUS_NO_CAPABILITY,
|
|
};
|
|
|
|
static int ahe50dc_fan_probe(struct i2c_client *client)
|
|
{
|
|
client->dev.platform_data = &ahe50dc_fan_data;
|
|
return pmbus_do_probe(client, &ahe50dc_fan_info);
|
|
}
|
|
|
|
static const struct i2c_device_id ahe50dc_fan_id[] = {
|
|
{ "ahe50dc_fan" },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ahe50dc_fan_id);
|
|
|
|
static const struct of_device_id __maybe_unused ahe50dc_fan_of_match[] = {
|
|
{ .compatible = "delta,ahe50dc-fan" },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ahe50dc_fan_of_match);
|
|
|
|
static struct i2c_driver ahe50dc_fan_driver = {
|
|
.driver = {
|
|
.name = "ahe50dc_fan",
|
|
.of_match_table = of_match_ptr(ahe50dc_fan_of_match),
|
|
},
|
|
.probe_new = ahe50dc_fan_probe,
|
|
.id_table = ahe50dc_fan_id,
|
|
};
|
|
module_i2c_driver(ahe50dc_fan_driver);
|
|
|
|
MODULE_AUTHOR("Zev Weiss <zev@bewilderbeest.net>");
|
|
MODULE_DESCRIPTION("Driver for Delta AHE-50DC power shelf fan control module");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_IMPORT_NS(PMBUS);
|