Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-23 12:42:02 +00:00
Code Issues Packages Projects Releases Wiki Activity
04e216d19e
linux/drivers/hwmon/pmbus/max16601.c
Stephen Kitt dd43193976 hwmon (pmbus) use simple i2c probe function 
pmbus_do_probe doesn't use the id information provided in its second
argument, so this can be removed, which then allows using the
single-parameter i2c probe function ("probe_new") for probes.

This avoids scanning the identifier tables during probes.

Drivers which didn't use the id are converted as-is; drivers which did
are modified as follows:

* if the information in i2c_client is sufficient, that's used instead
  (client->name);
* configured v. probed comparisons are performed by comparing the
  configured name to the detected name, instead of the ids; this
  involves strcmp but is still cheaper than comparing all the device
  names when scanning the tables;
* anything else is handled by calling i2c_match_id() with the same
  level of error-handling (if any) as before.

Additionally, the mismatch message in the ltc2978 driver is adjusted
so that it no longer assumes that the driver_data is an index into
ltc2978_id.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Acked-by: Wolfram Sang <wsa@kernel.org>
Link: https://lore.kernel.org/r/20200808210004.30880-1-steve@sk2.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2020-09-23 09:42:39 -07:00

314 lines
8.5 KiB
C
Raw Blame History

// SPDX-License-Identifier: GPL-2.0
/*
* Hardware monitoring driver for Maxim MAX16601
*
* Implementation notes:
*
* Ths chip supports two rails, VCORE and VSA. Telemetry information for the
* two rails is reported in two subsequent I2C addresses. The driver
* instantiates a dummy I2C client at the second I2C address to report
* information for the VSA rail in a single instance of the driver.
* Telemetry for the VSA rail is reported to the PMBus core in PMBus page 2.
*
* The chip reports input current using two separate methods. The input current
* reported with the standard READ_IIN command is derived from the output
* current. The first method is reported to the PMBus core with PMBus page 0,
* the second method is reported with PMBus page 1.
*
* The chip supports reading per-phase temperatures and per-phase input/output
* currents for VCORE. Telemetry is reported in vendor specific registers.
* The driver translates the vendor specific register values to PMBus standard
* register values and reports per-phase information in PMBus page 0.
*
* Copyright 2019, 2020 Google LLC.
*/
#include <linux/bits.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include "pmbus.h"
#define REG_SETPT_DVID 0xd1
#define DAC_10MV_MODE BIT(4)
#define REG_IOUT_AVG_PK 0xee
#define REG_IIN_SENSOR 0xf1
#define REG_TOTAL_INPUT_POWER 0xf2
#define REG_PHASE_ID 0xf3
#define CORE_RAIL_INDICATOR BIT(7)
#define REG_PHASE_REPORTING 0xf4
struct max16601_data {
struct pmbus_driver_info info;
struct i2c_client *vsa;
int iout_avg_pkg;
};
#define to_max16601_data(x) container_of(x, struct max16601_data, info)
static int max16601_read_byte(struct i2c_client *client, int page, int reg)
{
const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
struct max16601_data *data = to_max16601_data(info);
if (page > 0) {
if (page == 2) /* VSA */
return i2c_smbus_read_byte_data(data->vsa, reg);
return -EOPNOTSUPP;
}
return -ENODATA;
}
static int max16601_read_word(struct i2c_client *client, int page, int phase,
int reg)
{
const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
struct max16601_data *data = to_max16601_data(info);
u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
int ret;
switch (page) {
case 0: /* VCORE */
if (phase == 0xff)
return -ENODATA;
switch (reg) {
case PMBUS_READ_IIN:
case PMBUS_READ_IOUT:
case PMBUS_READ_TEMPERATURE_1:
ret = i2c_smbus_write_byte_data(client, REG_PHASE_ID,
phase);
if (ret)
return ret;
ret = i2c_smbus_read_block_data(client,
REG_PHASE_REPORTING,
buf);
if (ret < 0)
return ret;
if (ret < 6)
return -EIO;
switch (reg) {
case PMBUS_READ_TEMPERATURE_1:
return buf[1] << 8 | buf[0];
case PMBUS_READ_IOUT:
return buf[3] << 8 | buf[2];
case PMBUS_READ_IIN:
return buf[5] << 8 | buf[4];
default:
break;
}
}
return -EOPNOTSUPP;
case 1: /* VCORE, read IIN/PIN from sensor element */
switch (reg) {
case PMBUS_READ_IIN:
return i2c_smbus_read_word_data(client, REG_IIN_SENSOR);
case PMBUS_READ_PIN:
return i2c_smbus_read_word_data(client,
REG_TOTAL_INPUT_POWER);
default:
break;
}
return -EOPNOTSUPP;
case 2: /* VSA */
switch (reg) {
case PMBUS_VIRT_READ_IOUT_MAX:
ret = i2c_smbus_read_word_data(data->vsa,
REG_IOUT_AVG_PK);
if (ret < 0)
return ret;
if (sign_extend32(ret, 10) >
sign_extend32(data->iout_avg_pkg, 10))
data->iout_avg_pkg = ret;
return data->iout_avg_pkg;
case PMBUS_VIRT_RESET_IOUT_HISTORY:
return 0;
case PMBUS_IOUT_OC_FAULT_LIMIT:
case PMBUS_IOUT_OC_WARN_LIMIT:
case PMBUS_OT_FAULT_LIMIT:
case PMBUS_OT_WARN_LIMIT:
case PMBUS_READ_IIN:
case PMBUS_READ_IOUT:
case PMBUS_READ_TEMPERATURE_1:
case PMBUS_STATUS_WORD:
return i2c_smbus_read_word_data(data->vsa, reg);
default:
return -EOPNOTSUPP;
}
default:
return -EOPNOTSUPP;
}
}
static int max16601_write_byte(struct i2c_client *client, int page, u8 reg)
{
const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
struct max16601_data *data = to_max16601_data(info);
if (page == 2) {
if (reg == PMBUS_CLEAR_FAULTS)
return i2c_smbus_write_byte(data->vsa, reg);
return -EOPNOTSUPP;
}
return -ENODATA;
}
static int max16601_write_word(struct i2c_client *client, int page, int reg,
u16 value)
{
const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
struct max16601_data *data = to_max16601_data(info);
switch (page) {
case 0: /* VCORE */
return -ENODATA;
case 1: /* VCORE IIN/PIN from sensor element */
default:
return -EOPNOTSUPP;
case 2: /* VSA */
switch (reg) {
case PMBUS_VIRT_RESET_IOUT_HISTORY:
data->iout_avg_pkg = 0xfc00;
return 0;
case PMBUS_IOUT_OC_FAULT_LIMIT:
case PMBUS_IOUT_OC_WARN_LIMIT:
case PMBUS_OT_FAULT_LIMIT:
case PMBUS_OT_WARN_LIMIT:
return i2c_smbus_write_word_data(data->vsa, reg, value);
default:
return -EOPNOTSUPP;
}
}
}
static int max16601_identify(struct i2c_client *client,
struct pmbus_driver_info *info)
{
int reg;
reg = i2c_smbus_read_byte_data(client, REG_SETPT_DVID);
if (reg < 0)
return reg;
if (reg & DAC_10MV_MODE)
info->vrm_version[0] = vr13;
else
info->vrm_version[0] = vr12;
return 0;
}
static struct pmbus_driver_info max16601_info = {
.pages = 3,
.format[PSC_VOLTAGE_IN] = linear,
.format[PSC_VOLTAGE_OUT] = vid,
.format[PSC_CURRENT_IN] = linear,
.format[PSC_CURRENT_OUT] = linear,
.format[PSC_TEMPERATURE] = linear,
.format[PSC_POWER] = linear,
.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
PMBUS_HAVE_STATUS_INPUT |
PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
PMBUS_HAVE_POUT | PMBUS_PAGE_VIRTUAL | PMBUS_PHASE_VIRTUAL,
.func[1] = PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | PMBUS_PAGE_VIRTUAL,
.func[2] = PMBUS_HAVE_IIN | PMBUS_HAVE_STATUS_INPUT |
PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_PAGE_VIRTUAL,
.phases[0] = 8,
.pfunc[0] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP,
.pfunc[1] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT,
.pfunc[2] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP,
.pfunc[3] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT,
.pfunc[4] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP,
.pfunc[5] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT,
.pfunc[6] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP,
.pfunc[7] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT,
.identify = max16601_identify,
.read_byte_data = max16601_read_byte,
.read_word_data = max16601_read_word,
.write_byte = max16601_write_byte,
.write_word_data = max16601_write_word,
};
static void max16601_remove(void *_data)
{
struct max16601_data *data = _data;
i2c_unregister_device(data->vsa);
}
static int max16601_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
struct max16601_data *data;
int ret;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_BYTE_DATA |
I2C_FUNC_SMBUS_READ_BLOCK_DATA))
return -ENODEV;
ret = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, buf);
if (ret < 0)
return -ENODEV;
/* PMBUS_IC_DEVICE_ID is expected to return "MAX16601y.xx" */
if (ret < 11 || strncmp(buf, "MAX16601", 8)) {
buf[ret] = '\0';
dev_err(dev, "Unsupported chip '%s'\n", buf);
return -ENODEV;
}
ret = i2c_smbus_read_byte_data(client, REG_PHASE_ID);
if (ret < 0)
return ret;
if (!(ret & CORE_RAIL_INDICATOR)) {
dev_err(dev,
"Driver must be instantiated on CORE rail I2C address\n");
return -ENODEV;
}
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->iout_avg_pkg = 0xfc00;
data->vsa = i2c_new_dummy_device(client->adapter, client->addr + 1);
if (IS_ERR(data->vsa)) {
dev_err(dev, "Failed to register VSA client\n");
return PTR_ERR(data->vsa);
}
ret = devm_add_action_or_reset(dev, max16601_remove, data);
if (ret)
return ret;
data->info = max16601_info;
return pmbus_do_probe(client, &data->info);
}
static const struct i2c_device_id max16601_id[] = {
{"max16601", 0},
{}
};
MODULE_DEVICE_TABLE(i2c, max16601_id);
static struct i2c_driver max16601_driver = {
.driver = {
.name = "max16601",
},
.probe_new = max16601_probe,
.remove = pmbus_do_remove,
.id_table = max16601_id,
};
module_i2c_driver(max16601_driver);
MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
MODULE_DESCRIPTION("PMBus driver for Maxim MAX16601");
MODULE_LICENSE("GPL v2");
Reference in New Issue View Git Blame Copy Permalink