blob: c31889a036f01eefac6621796efb8e4bbcbecf13 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Hardware monitoring driver for Infineon TDA38640
*
* Copyright (c) 2023 9elements GmbH
*
*/
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/regulator/driver.h>
#include "pmbus.h"
static const struct regulator_desc __maybe_unused tda38640_reg_desc[] = {
PMBUS_REGULATOR_ONE("vout"),
};
struct tda38640_data {
struct pmbus_driver_info info;
u32 en_pin_lvl;
};
#define to_tda38640_data(x) container_of(x, struct tda38640_data, info)
/*
* Map PB_ON_OFF_CONFIG_POLARITY_HIGH to PB_OPERATION_CONTROL_ON.
*/
static int tda38640_read_byte_data(struct i2c_client *client, int page, int reg)
{
const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
struct tda38640_data *data = to_tda38640_data(info);
int ret, on_off_config, enabled;
if (reg != PMBUS_OPERATION)
return -ENODATA;
ret = pmbus_read_byte_data(client, page, reg);
if (ret < 0)
return ret;
on_off_config = pmbus_read_byte_data(client, page,
PMBUS_ON_OFF_CONFIG);
if (on_off_config < 0)
return on_off_config;
enabled = !!(on_off_config & PB_ON_OFF_CONFIG_POLARITY_HIGH);
enabled ^= data->en_pin_lvl;
if (enabled)
ret &= ~PB_OPERATION_CONTROL_ON;
else
ret |= PB_OPERATION_CONTROL_ON;
return ret;
}
/*
* Map PB_OPERATION_CONTROL_ON to PB_ON_OFF_CONFIG_POLARITY_HIGH.
*/
static int tda38640_write_byte_data(struct i2c_client *client, int page,
int reg, u8 byte)
{
const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
struct tda38640_data *data = to_tda38640_data(info);
int enable, ret;
if (reg != PMBUS_OPERATION)
return -ENODATA;
enable = !!(byte & PB_OPERATION_CONTROL_ON);
byte &= ~PB_OPERATION_CONTROL_ON;
ret = pmbus_write_byte_data(client, page, reg, byte);
if (ret < 0)
return ret;
enable ^= data->en_pin_lvl;
return pmbus_update_byte_data(client, page, PMBUS_ON_OFF_CONFIG,
PB_ON_OFF_CONFIG_POLARITY_HIGH,
enable ? 0 : PB_ON_OFF_CONFIG_POLARITY_HIGH);
}
static int svid_mode(struct i2c_client *client, struct tda38640_data *data)
{
/* PMBUS_MFR_READ(0xD0) + MTP Address offset */
u8 write_buf[] = {0xd0, 0x44, 0x00};
u8 read_buf[2];
int ret, svid;
bool off, reg_en_pin_pol;
struct i2c_msg msgs[2] = {
{
.addr = client->addr,
.flags = 0,
.buf = write_buf,
.len = sizeof(write_buf),
},
{
.addr = client->addr,
.flags = I2C_M_RD,
.buf = read_buf,
.len = sizeof(read_buf),
}
};
ret = i2c_transfer(client->adapter, msgs, 2);
if (ret < 0) {
dev_err(&client->dev, "i2c_transfer failed. %d", ret);
return ret;
}
/*
* 0x44[15] determines PMBus Operating Mode
* If bit is set then it is SVID mode.
*/
svid = !!(read_buf[1] & BIT(7));
/*
* Determine EN pin level for use in SVID mode.
* This is done with help of STATUS_BYTE bit 6(OFF) & ON_OFF_CONFIG bit 2(EN pin polarity).
*/
if (svid) {
ret = i2c_smbus_read_byte_data(client, PMBUS_STATUS_BYTE);
if (ret < 0)
return ret;
off = !!(ret & PB_STATUS_OFF);
ret = i2c_smbus_read_byte_data(client, PMBUS_ON_OFF_CONFIG);
if (ret < 0)
return ret;
reg_en_pin_pol = !!(ret & PB_ON_OFF_CONFIG_POLARITY_HIGH);
data->en_pin_lvl = off ^ reg_en_pin_pol;
}
return svid;
}
static struct pmbus_driver_info tda38640_info = {
.pages = 1,
.format[PSC_VOLTAGE_IN] = linear,
.format[PSC_VOLTAGE_OUT] = linear,
.format[PSC_CURRENT_OUT] = linear,
.format[PSC_CURRENT_IN] = linear,
.format[PSC_POWER] = linear,
.format[PSC_TEMPERATURE] = linear,
.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
| PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
| PMBUS_HAVE_IIN
| PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
| PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
| PMBUS_HAVE_POUT | PMBUS_HAVE_PIN,
#if IS_ENABLED(CONFIG_SENSORS_TDA38640_REGULATOR)
.num_regulators = 1,
.reg_desc = tda38640_reg_desc,
#endif
};
static int tda38640_probe(struct i2c_client *client)
{
struct tda38640_data *data;
int svid;
data = devm_kzalloc(&client->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
memcpy(&data->info, &tda38640_info, sizeof(tda38640_info));
if (IS_ENABLED(CONFIG_SENSORS_TDA38640_REGULATOR) &&
of_property_read_bool(client->dev.of_node, "infineon,en-pin-fixed-level")) {
svid = svid_mode(client, data);
if (svid < 0) {
dev_err_probe(&client->dev, svid, "Could not determine operating mode.");
return svid;
}
/*
* Apply ON_OFF_CONFIG workaround as enabling the regulator using the
* OPERATION register doesn't work in SVID mode.
*
* One should configure PMBUS_ON_OFF_CONFIG here, but
* PB_ON_OFF_CONFIG_POWERUP_CONTROL and PB_ON_OFF_CONFIG_EN_PIN_REQ
* are ignored by the device.
* Only PB_ON_OFF_CONFIG_POLARITY_HIGH has an effect.
*/
if (svid) {
data->info.read_byte_data = tda38640_read_byte_data;
data->info.write_byte_data = tda38640_write_byte_data;
}
}
return pmbus_do_probe(client, &data->info);
}
static const struct i2c_device_id tda38640_id[] = {
{"tda38640", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, tda38640_id);
static const struct of_device_id __maybe_unused tda38640_of_match[] = {
{ .compatible = "infineon,tda38640"},
{ },
};
MODULE_DEVICE_TABLE(of, tda38640_of_match);
/* This is the driver that will be inserted */
static struct i2c_driver tda38640_driver = {
.driver = {
.name = "tda38640",
.of_match_table = of_match_ptr(tda38640_of_match),
},
.probe = tda38640_probe,
.id_table = tda38640_id,
};
module_i2c_driver(tda38640_driver);
MODULE_AUTHOR("Patrick Rudolph <patrick.rudolph@9elements.com>");
MODULE_DESCRIPTION("PMBus driver for Infineon TDA38640");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS(PMBUS);