From patchwork Mon Nov 20 04:42:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Jeffery X-Patchwork-Id: 10065941 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 9CB5D602B7 for ; Mon, 20 Nov 2017 04:43:45 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9012B28F47 for ; Mon, 20 Nov 2017 04:43:45 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8464728F4B; Mon, 20 Nov 2017 04:43:45 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DDE7E28F4A for ; Mon, 20 Nov 2017 04:43:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751145AbdKTEnB (ORCPT ); Sun, 19 Nov 2017 23:43:01 -0500 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:43355 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751107AbdKTEm6 (ORCPT ); Sun, 19 Nov 2017 23:42:58 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id D129520BB1; Sun, 19 Nov 2017 23:42:57 -0500 (EST) Received: from frontend2 ([10.202.2.161]) by compute4.internal (MEProxy); Sun, 19 Nov 2017 23:42:57 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aj.id.au; h=cc :date:from:in-reply-to:in-reply-to:message-id:references :references:subject:to:x-me-sender:x-me-sender:x-sasl-enc; s= fm1; bh=a+wCzDAFjN2eHH58+ePU8EZ/CwHl59qrrCnZH81DxTc=; b=I2GT0Ccn ftLhuIyweTJiPgFTTVKACj2FrhmQcm274qtHqfFJzC+hkkC/wnGYIDS4dMz2OTeu 4Y1J7XfvaKaxX6+BGdnFoD4p9+b1XqdjDIFqhgPOGTYJDd/TNkSOrTh9lB1nOOd1 jE56+d4OHR95zfFhwwVZZpXlOVETklKZ1lUKP5uERhUBQ0Vk0B5wJhchIHDMm+bX lKVyoFhF5iAUUmcOd2aDi1YaXhjVUD8uazoACozZmiJVX/gxVMgHrp/C+YtVbM77 A8rFK/YN48ndv6iyGwHqe5PNwJzQy7o03gvP3qKrY6EFowEmMdG+eNUMYzh8zVJ6 Wd5T9Q4g/XWeYg== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:date:from:in-reply-to:in-reply-to :message-id:references:references:subject:to:x-me-sender :x-me-sender:x-sasl-enc; s=fm1; bh=a+wCzDAFjN2eHH58+ePU8EZ/CwHl5 9qrrCnZH81DxTc=; b=BK9qAtXxBcdpy/T932U4o1AxyMUNn5NxDQHKMa2yj0H0b S4hbmh4ZixlAxix6v5pJesHvePlqiuG5Y7vceOtRpfp1Bxnk92bMZpHs09+IUez7 NWpESGGkPu2Up71iKbNTipHqSD9iUZZhrY85nyJ5eMFkDP0HIYL3ZpAKIO8FKMrx 4Ds5yA0wPx3UDVH6sJxEOAXAt8Rj9UcHx1TmJE9yVTvuuZKjepunef1wbuiIpvAA tGEMkopD3EAREBIV7F2eSqZ2VNPhmhxZqJXvTe2JGJAvYFUi8VmML681a/tBfCiJ BcViJ/O2B+FKGoHb+K7RbxfPLiPWBBRH+6lnkm3UQ== X-ME-Sender: Received: from dave.base64.com.au (unknown [203.0.153.9]) by mail.messagingengine.com (Postfix) with ESMTPA id EC41C240F8; Sun, 19 Nov 2017 23:42:53 -0500 (EST) From: Andrew Jeffery To: linux-hwmon@vger.kernel.org Cc: Andrew Jeffery , linux@roeck-us.net, jdelvare@suse.com, corbet@lwn.net, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, joel@jms.id.au, openbmc@lists.ozlabs.org Subject: [PATCH v6 2/4] pmbus (max31785): Add fan control Date: Mon, 20 Nov 2017 15:12:04 +1030 Message-Id: <8c06a1a1fcb67745fb9015b5c3f69f6f12ae0b0f.1511152748.git-series.andrew@aj.id.au> X-Mailer: git-send-email 2.14.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-hwmon-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The implementation makes use of the new fan control virtual registers exposed by the pmbus core. It mixes use of the default implementations with some overrides via the read/write handlers to handle FAN_COMMAND_1 on the MAX31785, whose definition breaks the value range into various control bands dependent on RPM or PWM mode. Signed-off-by: Andrew Jeffery --- Documentation/hwmon/max31785 | 7 ++- drivers/hwmon/pmbus/max31785.c | 138 +++++++++++++++++++++++++++++++++- 2 files changed, 144 insertions(+), 1 deletion(-) diff --git a/Documentation/hwmon/max31785 b/Documentation/hwmon/max31785 index 45fb6093dec2..7b0a0a8cdb6b 100644 --- a/Documentation/hwmon/max31785 +++ b/Documentation/hwmon/max31785 @@ -32,6 +32,7 @@ Sysfs attributes fan[1-4]_alarm Fan alarm. fan[1-4]_fault Fan fault. fan[1-4]_input Fan RPM. +fan[1-4]_target Fan input target in[1-6]_crit Critical maximum output voltage in[1-6]_crit_alarm Output voltage critical high alarm @@ -44,6 +45,12 @@ in[1-6]_max_alarm Output voltage high alarm in[1-6]_min Minimum output voltage in[1-6]_min_alarm Output voltage low alarm +pwm[1-4] Fan target duty cycle (0..255) +pwm[1-4]_enable 0: Full-speed + 1: Manual PWM control + 2: Automatic PWM (tach-feedback RPM fan-control) + 3: Automatic closed-loop (temp-feedback fan-control) + temp[1-11]_crit Critical high temperature temp[1-11]_crit_alarm Chip temperature critical high alarm temp[1-11]_input Measured temperature diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c index 9313849d5160..8706a696c89a 100644 --- a/drivers/hwmon/pmbus/max31785.c +++ b/drivers/hwmon/pmbus/max31785.c @@ -20,8 +20,136 @@ enum max31785_regs { #define MAX31785_NR_PAGES 23 +static int max31785_get_pwm(struct i2c_client *client, int page) +{ + int rv; + + rv = pmbus_get_fan_rate_device(client, page, 0, percent); + if (rv < 0) + return rv; + else if (rv >= 0x8000) + return 0; + else if (rv >= 0x2711) + return 0x2710; + + return rv; +} + +static int max31785_get_pwm_mode(struct i2c_client *client, int page) +{ + int config; + int command; + + config = pmbus_read_byte_data(client, page, PMBUS_FAN_CONFIG_12); + if (config < 0) + return config; + + command = pmbus_read_word_data(client, page, PMBUS_FAN_COMMAND_1); + if (command < 0) + return command; + + if (config & PB_FAN_1_RPM) + return (command >= 0x8000) ? 3 : 2; + + if (command >= 0x8000) + return 3; + else if (command >= 0x2711) + return 0; + + return 1; +} + +static int max31785_read_word_data(struct i2c_client *client, int page, + int reg) +{ + int rv; + + switch (reg) { + case PMBUS_VIRT_PWM_1: + rv = max31785_get_pwm(client, page); + break; + case PMBUS_VIRT_PWM_ENABLE_1: + rv = max31785_get_pwm_mode(client, page); + break; + default: + rv = -ENODATA; + break; + } + + return rv; +} + +static inline u32 max31785_scale_pwm(u32 sensor_val) +{ + /* + * The datasheet describes the accepted value range for manual PWM as + * [0, 0x2710], while the hwmon pwmX sysfs interface accepts values in + * [0, 255]. The MAX31785 uses DIRECT mode to scale the FAN_COMMAND + * registers and in PWM mode the coefficients are m=1, b=0, R=2. The + * important observation here is that 0x2710 == 10000 == 100 * 100. + * + * R=2 (== 10^2 == 100) accounts for scaling the value provided at the + * sysfs interface into the required hardware resolution, but it does + * not yet yield a value that we can write to the device (this initial + * scaling is handled by pmbus_data2reg()). Multiplying by 100 below + * translates the parameter value into the percentage units required by + * PMBus, and then we scale back by 255 as required by the hwmon pwmX + * interface to yield the percentage value at the appropriate + * resolution for hardware. + */ + return (sensor_val * 100) / 255; +} + +static int max31785_pwm_enable(struct i2c_client *client, int page, + u16 word) +{ + int config = 0; + int rate; + + switch (word) { + case 0: + rate = 0x7fff; + break; + case 1: + rate = pmbus_get_fan_rate_cached(client, page, 0, percent); + if (rate < 0) + return rate; + rate = max31785_scale_pwm(rate); + break; + case 2: + config = PB_FAN_1_RPM; + rate = pmbus_get_fan_rate_cached(client, page, 0, rpm); + if (rate < 0) + return rate; + break; + case 3: + rate = 0xffff; + break; + default: + return -EINVAL; + } + + return pmbus_update_fan(client, page, 0, config, PB_FAN_1_RPM, rate); +} + +static int max31785_write_word_data(struct i2c_client *client, int page, + int reg, u16 word) +{ + switch (reg) { + case PMBUS_VIRT_PWM_1: + return pmbus_update_fan(client, page, 0, 0, PB_FAN_1_RPM, + max31785_scale_pwm(word)); + case PMBUS_VIRT_PWM_ENABLE_1: + return max31785_pwm_enable(client, page, word); + default: + break; + } + + return -ENODATA; +} + #define MAX31785_FAN_FUNCS \ - (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12) + (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_PWM12) #define MAX31785_TEMP_FUNCS \ (PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP) @@ -32,11 +160,19 @@ enum max31785_regs { static const struct pmbus_driver_info max31785_info = { .pages = MAX31785_NR_PAGES, + .write_word_data = max31785_write_word_data, + .read_word_data = max31785_read_word_data, + /* RPM */ .format[PSC_FAN] = direct, .m[PSC_FAN] = 1, .b[PSC_FAN] = 0, .R[PSC_FAN] = 0, + /* PWM */ + .format[PSC_PWM] = direct, + .m[PSC_PWM] = 1, + .b[PSC_PWM] = 0, + .R[PSC_PWM] = 2, .func[0] = MAX31785_FAN_FUNCS, .func[1] = MAX31785_FAN_FUNCS, .func[2] = MAX31785_FAN_FUNCS,