From e0f0307ac16fe69c6f9dcc8d14b532bc608fc989 Mon Sep 17 00:00:00 2001 From: Zev Weiss Date: Fri, 18 Feb 2022 16:03:59 -0800 Subject: [PATCH] hwmon: (pmbus) Add get_error_flags support to regulator ops The various PMBus status bits don't all map perfectly to the more limited set of REGULATOR_ERROR_* flags, but there's a reasonable number where they correspond well enough. Signed-off-by: Zev Weiss Link: https://lore.kernel.org/r/20220219000359.19985-1-zev@bewilderbeest.net [groeck: Added missing locking] Signed-off-by: Guenter Roeck --- drivers/hwmon/pmbus/pmbus_core.c | 114 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 114 insertions(+) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index b1386a4..8eed796 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -2432,10 +2432,124 @@ static int pmbus_regulator_disable(struct regulator_dev *rdev) return _pmbus_regulator_on_off(rdev, 0); } +/* A PMBus status flag and the corresponding REGULATOR_ERROR_* flag */ +struct pmbus_regulator_status_assoc { + int pflag, rflag; +}; + +/* PMBus->regulator bit mappings for a PMBus status register */ +struct pmbus_regulator_status_category { + int func; + int reg; + const struct pmbus_regulator_status_assoc *bits; /* zero-terminated */ +}; + +static const struct pmbus_regulator_status_category pmbus_regulator_flag_map[] = { + { + .func = PMBUS_HAVE_STATUS_VOUT, + .reg = PMBUS_STATUS_VOUT, + .bits = (const struct pmbus_regulator_status_assoc[]) { + { PB_VOLTAGE_UV_WARNING, REGULATOR_ERROR_UNDER_VOLTAGE_WARN }, + { PB_VOLTAGE_UV_FAULT, REGULATOR_ERROR_UNDER_VOLTAGE }, + { PB_VOLTAGE_OV_WARNING, REGULATOR_ERROR_OVER_VOLTAGE_WARN }, + { PB_VOLTAGE_OV_FAULT, REGULATOR_ERROR_REGULATION_OUT }, + { }, + }, + }, { + .func = PMBUS_HAVE_STATUS_IOUT, + .reg = PMBUS_STATUS_IOUT, + .bits = (const struct pmbus_regulator_status_assoc[]) { + { PB_IOUT_OC_WARNING, REGULATOR_ERROR_OVER_CURRENT_WARN }, + { PB_IOUT_OC_FAULT, REGULATOR_ERROR_OVER_CURRENT }, + { PB_IOUT_OC_LV_FAULT, REGULATOR_ERROR_OVER_CURRENT }, + { }, + }, + }, { + .func = PMBUS_HAVE_STATUS_TEMP, + .reg = PMBUS_STATUS_TEMPERATURE, + .bits = (const struct pmbus_regulator_status_assoc[]) { + { PB_TEMP_OT_WARNING, REGULATOR_ERROR_OVER_TEMP_WARN }, + { PB_TEMP_OT_FAULT, REGULATOR_ERROR_OVER_TEMP }, + { }, + }, + }, +}; + +static int pmbus_regulator_get_error_flags(struct regulator_dev *rdev, unsigned int *flags) +{ + int i, status; + const struct pmbus_regulator_status_category *cat; + const struct pmbus_regulator_status_assoc *bit; + struct device *dev = rdev_get_dev(rdev); + struct i2c_client *client = to_i2c_client(dev->parent); + struct pmbus_data *data = i2c_get_clientdata(client); + u8 page = rdev_get_id(rdev); + int func = data->info->func[page]; + + *flags = 0; + + mutex_lock(&data->update_lock); + + for (i = 0; i < ARRAY_SIZE(pmbus_regulator_flag_map); i++) { + cat = &pmbus_regulator_flag_map[i]; + if (!(func & cat->func)) + continue; + + status = pmbus_read_byte_data(client, page, cat->reg); + if (status < 0) { + mutex_unlock(&data->update_lock); + return status; + } + + for (bit = cat->bits; bit->pflag; bit++) { + if (status & bit->pflag) + *flags |= bit->rflag; + } + } + + /* + * Map what bits of STATUS_{WORD,BYTE} we can to REGULATOR_ERROR_* + * bits. Some of the other bits are tempting (especially for cases + * where we don't have the relevant PMBUS_HAVE_STATUS_* + * functionality), but there's an unfortunate ambiguity in that + * they're defined as indicating a fault *or* a warning, so we can't + * easily determine whether to report REGULATOR_ERROR_ or + * REGULATOR_ERROR__WARN. + */ + status = pmbus_get_status(client, page, PMBUS_STATUS_WORD); + mutex_unlock(&data->update_lock); + if (status < 0) + return status; + + if (pmbus_regulator_is_enabled(rdev) && (status & PB_STATUS_OFF)) + *flags |= REGULATOR_ERROR_FAIL; + + /* + * Unlike most other status bits, PB_STATUS_{IOUT_OC,VOUT_OV} are + * defined strictly as fault indicators (not warnings). + */ + if (status & PB_STATUS_IOUT_OC) + *flags |= REGULATOR_ERROR_OVER_CURRENT; + if (status & PB_STATUS_VOUT_OV) + *flags |= REGULATOR_ERROR_REGULATION_OUT; + + /* + * If we haven't discovered any thermal faults or warnings via + * PMBUS_STATUS_TEMPERATURE, map PB_STATUS_TEMPERATURE to a warning as + * a (conservative) best-effort interpretation. + */ + if (!(*flags & (REGULATOR_ERROR_OVER_TEMP | REGULATOR_ERROR_OVER_TEMP_WARN)) && + (status & PB_STATUS_TEMPERATURE)) + *flags |= REGULATOR_ERROR_OVER_TEMP_WARN; + + return 0; +} + const struct regulator_ops pmbus_regulator_ops = { .enable = pmbus_regulator_enable, .disable = pmbus_regulator_disable, .is_enabled = pmbus_regulator_is_enabled, + .get_error_flags = pmbus_regulator_get_error_flags, }; EXPORT_SYMBOL_NS_GPL(pmbus_regulator_ops, PMBUS); -- 2.7.4