From patchwork Sat Feb 19 00:03:59 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zev Weiss X-Patchwork-Id: 12752013 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F8C2C433EF for ; Sat, 19 Feb 2022 00:04:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233937AbiBSAEa (ORCPT ); Fri, 18 Feb 2022 19:04:30 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:56884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235810AbiBSAE3 (ORCPT ); Fri, 18 Feb 2022 19:04:29 -0500 Received: from thorn.bewilderbeest.net (thorn.bewilderbeest.net [IPv6:2605:2700:0:5::4713:9cab]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05816273753; Fri, 18 Feb 2022 16:04:11 -0800 (PST) Received: from hatter.bewilderbeest.net (174-21-187-98.tukw.qwest.net [174.21.187.98]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: zev) by thorn.bewilderbeest.net (Postfix) with ESMTPSA id 0A2F2135; Fri, 18 Feb 2022 16:04:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bewilderbeest.net; s=thorn; t=1645229051; bh=fRpcrn9aRe9EB3cR2DrtWCDg9U+Fe9vYEshHpgA5N40=; h=From:To:Cc:Subject:Date:From; b=UUNjOq1EkrefBQfoigV/yEWxQ5UP8sHroqNLu3a41MS89bovPx99hBDqDU+eRCfP/ QTHfKqWJMoLNYuaHckUwp9M8QlYbnMLHvnYBkY37wZSkfQ5ZLcyAL0GwnGete/HbSW xqAgdtHJ/czvXlx6oNqTaUzAjDVHl9tyUCpVdQhU= From: Zev Weiss To: Guenter Roeck , Jean Delvare , linux-hwmon@vger.kernel.org Cc: Liam Girdwood , Mark Brown , linux-kernel@vger.kernel.org, Zev Weiss Subject: [PATCH v2] hwmon: (pmbus) Add get_error_flags support to regulator ops Date: Fri, 18 Feb 2022 16:03:59 -0800 Message-Id: <20220219000359.19985-1-zev@bewilderbeest.net> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org 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 --- Changes since v1 [0]: - split patch out of power-efuse driver series - simplified pmbus_get_status() call - added comment explaining PB_STATUS_{IOUT_OC,VOUT_OV} checks - added fallback PB_STATUS_TEMPERATURE check mapping it to REGULATOR_ERROR_OVER_TEMP_WARN [0] https://lore.kernel.org/openbmc/20220217104444.7695-2-zev@bewilderbeest.net/ drivers/hwmon/pmbus/pmbus_core.c | 109 +++++++++++++++++++++++++++++++ 1 file changed, 109 insertions(+) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 776ee2237be2..6f05c271bdf8 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -2417,10 +2417,119 @@ 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; + + 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) + 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); + 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);