diff options
Diffstat (limited to 'drivers/hwmon/pmbus/fsp-3y.c')
| -rw-r--r-- | drivers/hwmon/pmbus/fsp-3y.c | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/fsp-3y.c b/drivers/hwmon/pmbus/fsp-3y.c new file mode 100644 index 000000000000..284b73aaed46 --- /dev/null +++ b/drivers/hwmon/pmbus/fsp-3y.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Hardware monitoring driver for FSP 3Y-Power PSUs + * + * Copyright (c) 2021 Václav Kubernát, CESNET + * + * This driver is mostly reverse engineered with the help of a tool called pmbus_peek written by + * David Brownell (and later adopted by Jan Kundrát). The device has some sort of a timing issue + * when switching pages, details are explained in the code. The driver support is limited. It + * exposes only the values, that have been tested to work correctly. Unsupported values either + * aren't supported by the devices or their encondings are unknown. + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include "pmbus.h" + +#define YM2151_PAGE_12V_LOG 0x00 +#define YM2151_PAGE_12V_REAL 0x00 +#define YM2151_PAGE_5VSB_LOG 0x01 +#define YM2151_PAGE_5VSB_REAL 0x20 +#define YH5151E_PAGE_12V_LOG 0x00 +#define YH5151E_PAGE_12V_REAL 0x00 +#define YH5151E_PAGE_5V_LOG 0x01 +#define YH5151E_PAGE_5V_REAL 0x10 +#define YH5151E_PAGE_3V3_LOG 0x02 +#define YH5151E_PAGE_3V3_REAL 0x11 + +enum chips { + ym2151e, + yh5151e +}; + +struct fsp3y_data { + struct pmbus_driver_info info; + int chip; + int page; +}; + +#define to_fsp3y_data(x) container_of(x, struct fsp3y_data, info) + +static int page_log_to_page_real(int page_log, enum chips chip) +{ + switch (chip) { + case ym2151e: + switch (page_log) { + case YM2151_PAGE_12V_LOG: + return YM2151_PAGE_12V_REAL; + case YM2151_PAGE_5VSB_LOG: + return YM2151_PAGE_5VSB_REAL; + } + return -EINVAL; + case yh5151e: + switch (page_log) { + case YH5151E_PAGE_12V_LOG: + return YH5151E_PAGE_12V_REAL; + case YH5151E_PAGE_5V_LOG: + return YH5151E_PAGE_5V_LOG; + case YH5151E_PAGE_3V3_LOG: + return YH5151E_PAGE_3V3_REAL; + } + return -EINVAL; + } + + return -EINVAL; +} + +static int set_page(struct i2c_client *client, int page_log) +{ + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); + struct fsp3y_data *data = to_fsp3y_data(info); + int rv; + int page_real; + + if (page_log < 0) + return 0; + + page_real = page_log_to_page_real(page_log, data->chip); + if (page_real < 0) + return page_real; + + if (data->page != page_real) { + rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page_real); + if (rv < 0) + return rv; + + data->page = page_real; + + /* + * Testing showed that the device has a timing issue. After + * setting a page, it takes a while, before the device actually + * gives the correct values from the correct page. 20 ms was + * tested to be enough to not give wrong values (15 ms wasn't + * enough). + */ + usleep_range(20000, 30000); + } + + return 0; +} + +static int fsp3y_read_byte_data(struct i2c_client *client, int page, int reg) +{ + int rv; + + rv = set_page(client, page); + if (rv < 0) + return rv; + + return i2c_smbus_read_byte_data(client, reg); +} + +static int fsp3y_read_word_data(struct i2c_client *client, int page, int phase, int reg) +{ + int rv; + + /* + * This masks commands which weren't tested to work correctly. Some of + * the masked commands return 0xFFFF. These would probably get tagged as + * invalid by pmbus_core. Other ones do return values which might be + * useful (that is, they are not 0xFFFF), but their encoding is unknown, + * and so they are unsupported. + */ + switch (reg) { + case PMBUS_READ_FAN_SPEED_1: + case PMBUS_READ_IIN: + case PMBUS_READ_IOUT: + case PMBUS_READ_PIN: + case PMBUS_READ_POUT: + case PMBUS_READ_TEMPERATURE_1: + case PMBUS_READ_TEMPERATURE_2: + case PMBUS_READ_TEMPERATURE_3: + case PMBUS_READ_VIN: + case PMBUS_READ_VOUT: + case PMBUS_STATUS_WORD: + break; + default: + return -ENXIO; + } + + rv = set_page(client, page); + if (rv < 0) + return rv; + + return i2c_smbus_read_word_data(client, reg); +} + +static struct pmbus_driver_info fsp3y_info[] = { + [ym2151e] = { + .pages = 2, + .func[YM2151_PAGE_12V_LOG] = + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | + PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | + PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | + PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | + PMBUS_HAVE_FAN12, + .func[YM2151_PAGE_5VSB_LOG] = + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT, + PMBUS_HAVE_IIN, + .read_word_data = fsp3y_read_word_data, + .read_byte_data = fsp3y_read_byte_data, + }, + [yh5151e] = { + .pages = 3, + .func[YH5151E_PAGE_12V_LOG] = + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | + PMBUS_HAVE_POUT | + PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3, + .func[YH5151E_PAGE_5V_LOG] = + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | + PMBUS_HAVE_POUT, + .func[YH5151E_PAGE_3V3_LOG] = + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | + PMBUS_HAVE_POUT, + .read_word_data = fsp3y_read_word_data, + .read_byte_data = fsp3y_read_byte_data, + } +}; + +static int fsp3y_detect(struct i2c_client *client) +{ + int rv; + u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; + + rv = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf); + if (rv < 0) + return rv; + + buf[rv] = '\0'; + + if (rv == 8) { + if (!strcmp(buf, "YM-2151E")) + return ym2151e; + else if (!strcmp(buf, "YH-5151E")) + return yh5151e; + } + + dev_err(&client->dev, "Unsupported model %.*s\n", rv, buf); + return -ENODEV; +} + +static const struct i2c_device_id fsp3y_id[] = { + {"ym2151e", ym2151e}, + {"yh5151e", yh5151e}, + { } +}; + +static int fsp3y_probe(struct i2c_client *client) +{ + struct fsp3y_data *data; + const struct i2c_device_id *id; + int rv; + + data = devm_kzalloc(&client->dev, sizeof(struct fsp3y_data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->chip = fsp3y_detect(client); + if (data->chip < 0) + return data->chip; + + id = i2c_match_id(fsp3y_id, client); + if (data->chip != id->driver_data) + dev_warn(&client->dev, "Device mismatch: Configured %s (%d), detected %d\n", + id->name, (int)id->driver_data, data->chip); + + rv = i2c_smbus_read_byte_data(client, PMBUS_PAGE); + if (rv < 0) + return rv; + data->page = rv; + + data->info = fsp3y_info[data->chip]; + + return pmbus_do_probe(client, &data->info); +} + +MODULE_DEVICE_TABLE(i2c, fsp3y_id); + +static struct i2c_driver fsp3y_driver = { + .driver = { + .name = "fsp3y", + }, + .probe_new = fsp3y_probe, + .id_table = fsp3y_id +}; + +module_i2c_driver(fsp3y_driver); + +MODULE_AUTHOR("Václav Kubernát"); +MODULE_DESCRIPTION("PMBus driver for FSP/3Y-Power power supplies"); +MODULE_LICENSE("GPL"); |