From patchwork Tue Dec 8 23:12:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vadim Pasternak X-Patchwork-Id: 11960019 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6670CC433FE for ; Tue, 8 Dec 2020 23:14:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3324A22203 for ; Tue, 8 Dec 2020 23:14:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731300AbgLHXOW (ORCPT ); Tue, 8 Dec 2020 18:14:22 -0500 Received: from mail-il-dmz.mellanox.com ([193.47.165.129]:55640 "EHLO mellanox.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730631AbgLHXOW (ORCPT ); Tue, 8 Dec 2020 18:14:22 -0500 Received: from Internal Mail-Server by MTLPINE1 (envelope-from vadimp@nvidia.com) with SMTP; 9 Dec 2020 01:13:30 +0200 Received: from r-build-lowlevel.mtr.labs.mlnx. (r-build-lowlevel.mtr.labs.mlnx [10.209.0.190]) by labmailer.mlnx (8.13.8/8.13.8) with ESMTP id 0B8NDUNK015824; Wed, 9 Dec 2020 01:13:30 +0200 From: Vadim Pasternak To: linux@roeck-us.net Cc: linux-hwmon@vger.kernel.org, Vadim Pasternak Subject: [PATCH hwmon-next v2 1/1] hwmon: (mlxreg-fan) Add support for fan drawers capability and present registers Date: Wed, 9 Dec 2020 01:12:59 +0200 Message-Id: <20201208231259.47955-1-vadimp@nvidia.com> X-Mailer: git-send-email 2.11.0 Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org Add support for fan drawer's capability and present registers in order to set mapping between the fan drawers and tachometers. Some systems are equipped with fan drawers with one tachometer inside. Others with fan drawers with several tachometers inside. Using present register along with tachometer-to-drawer mapping allows to skip reading missed tachometers and expose input for them as zero, instead of exposing fault code returned by hardware. Signed-off-by: Vadim Pasternak --- v1->v2: Comments pointed out by Guenter: - Simplify drawers number calculation in mlxreg_fan_config(). - Validate that the number of drawers and tachometers, supported on system, both are not zero. Otherwise return error. Added by Vadim: - Change comment in mlxreg_fan_read() regarding FAN presence - use "FAN is inserted" instead of "FAN is physically connected", t clarify that "FAN presence" can be changed dynamically. --- drivers/hwmon/mlxreg-fan.c | 48 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 47 insertions(+), 1 deletion(-) diff --git a/drivers/hwmon/mlxreg-fan.c b/drivers/hwmon/mlxreg-fan.c index ed8d59d4eecb..8a69044140a6 100644 --- a/drivers/hwmon/mlxreg-fan.c +++ b/drivers/hwmon/mlxreg-fan.c @@ -67,11 +67,13 @@ * @connected: indicates if tachometer is connected; * @reg: register offset; * @mask: fault mask; + * @prsnt: present register offset; */ struct mlxreg_fan_tacho { bool connected; u32 reg; u32 mask; + u32 prsnt; }; /* @@ -92,6 +94,7 @@ struct mlxreg_fan_pwm { * @regmap: register map of parent device; * @tacho: tachometer data; * @pwm: PWM data; + * @tachos_per_drwr - number of tachometers per drawer; * @samples: minimum allowed samples per pulse; * @divider: divider value for tachometer RPM calculation; * @cooling: cooling device levels; @@ -103,6 +106,7 @@ struct mlxreg_fan { struct mlxreg_core_platform_data *pdata; struct mlxreg_fan_tacho tacho[MLXREG_FAN_MAX_TACHO]; struct mlxreg_fan_pwm pwm; + int tachos_per_drwr; int samples; int divider; u8 cooling_levels[MLXREG_FAN_MAX_STATE + 1]; @@ -123,6 +127,26 @@ mlxreg_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, tacho = &fan->tacho[channel]; switch (attr) { case hwmon_fan_input: + /* + * Check FAN presence: FAN related bit in presence register is one, + * if FAN is not physically connected, zero - otherwise. + */ + if (tacho->prsnt) { + err = regmap_read(fan->regmap, tacho->prsnt, ®val); + if (err) + return err; + + /* + * Map channel to presence bit - drawer can be equipped with + * one or few FANs, while presence is indicated per drawer. + */ + if ((BIT(channel / fan->tachos_per_drwr) & regval)) { + /* FAN is not connected - return zero for FAN speed. */ + *val = 0; + return 0; + } + } + err = regmap_read(fan->regmap, tacho->reg, ®val); if (err) return err; @@ -388,9 +412,9 @@ static int mlxreg_fan_speed_divider_get(struct mlxreg_fan *fan, static int mlxreg_fan_config(struct mlxreg_fan *fan, struct mlxreg_core_platform_data *pdata) { + int tacho_num = 0, regval, drwr_avail = 0, tacho_avail = 0, i; struct mlxreg_core_data *data = pdata->data; bool configured = false; - int tacho_num = 0, i; int err; fan->samples = MLXREG_FAN_TACHO_SAMPLES_PER_PULSE_DEF; @@ -415,7 +439,9 @@ static int mlxreg_fan_config(struct mlxreg_fan *fan, fan->tacho[tacho_num].reg = data->reg; fan->tacho[tacho_num].mask = data->mask; + fan->tacho[tacho_num].prsnt = data->reg_prsnt; fan->tacho[tacho_num++].connected = true; + tacho_avail++; } else if (strnstr(data->label, "pwm", sizeof(data->label))) { if (fan->pwm.connected) { dev_err(fan->dev, "duplicate pwm entry: %s\n", @@ -453,6 +479,26 @@ static int mlxreg_fan_config(struct mlxreg_fan *fan, } } + if (pdata->capability) { + /* Obtain the number of FAN drawers, supported by system. */ + err = regmap_read(fan->regmap, pdata->capability, ®val); + if (err) { + dev_err(fan->dev, "Failed to query capability register 0x%08x\n", + pdata->capability); + return err; + } + + drwr_avail = hweight32(regval); + if (!tacho_avail || !drwr_avail) { + dev_err(fan->dev, "Configuration is invalid: drawers num %d tachos num %d\n", + drwr_avail, tacho_avail); + return -EINVAL; + } + + /* Set the number of tachometers per one drawer. */ + fan->tachos_per_drwr = tacho_avail / drwr_avail; + } + /* Init cooling levels per PWM state. */ for (i = 0; i < MLXREG_FAN_SPEED_MIN_LEVEL; i++) fan->cooling_levels[i] = MLXREG_FAN_SPEED_MIN_LEVEL;