From patchwork Sat Nov 18 03:26:06 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Jeffery X-Patchwork-Id: 10064319 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 2C0C4602B8 for ; Sat, 18 Nov 2017 03:27:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 082032ADA7 for ; Sat, 18 Nov 2017 03:27:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F0E172ADB4; Sat, 18 Nov 2017 03:27:27 +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 6BC2E2ADA7 for ; Sat, 18 Nov 2017 03:27:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760500AbdKRD1I (ORCPT ); Fri, 17 Nov 2017 22:27:08 -0500 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:53535 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760368AbdKRD1B (ORCPT ); Fri, 17 Nov 2017 22:27:01 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailout.nyi.internal (Postfix) with ESMTP id 429FE20D38; Fri, 17 Nov 2017 22:27:00 -0500 (EST) Received: from frontend2 ([10.202.2.161]) by compute4.internal (MEProxy); Fri, 17 Nov 2017 22:27:00 -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=iVkeoY6+WQHvGgBExIFjldOdgkDfJZgs4Ocw6yep5aE=; b=Am8glbox geoxtcBHNWPvOj2QM9r6wzFUSXyCmrwwqiH1Fwa+NdyI1x0GfMIOIK7/QarCQkC9 +k6JTwAhunA2NRFj2uNhXpZ29d6Ed8rFHMbmKzOsrr1Mr2e0MRs3jkpSSfJApMm3 7eufoBdMW44BrwMHzqzaQBRCQb9l95QEIX76StmsW8/ufiygOIxLuwijQj9xQ9KH N6GXNGjZ/CSXzjnP6OsaUreOocvb8L0yD6s0xItnjIj6fjOTG8jkBfgKcnFwt5IH Eh6z+NJEI87UKc9tKU7lxaeAPC2hwKMe8wB5TMnb21RBkE4teQbkME8Z0Wlfcgai mmWPjwtS5bTklw== 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=iVkeoY6+WQHvGgBExIFjldOdgkDfJ Zgs4Ocw6yep5aE=; b=dybpbK38T7EXo9WOIFHhvnjnf7inKNJuFybCFSoVawEDN GrSyKkXnrs0jRTq7KNF+WgOin8g6cUd94CB0eeRIQiYWJZPqCq46oxgwIZwAlVJp FQvRKJcHlUWWz148k/fSMqVxLSL5CtOfGfQnsoq24FP1H4VhuLBF9qlCIH8i7wVz OkkHoSjzFGrTp+wP2H3ahWxUUiIOl9oHtz+3dlakCWKTW/23+v/VKrDnJElE/5WB Khu2ZTJh24mpYVaeIHLpaMRxi7j8zdlI3ojbzSHv7ovORfaHJFIwnWu/f4ZzWlk6 T0ofZZz9m4Mtt1/uHmnDz63+lWjLxOPUMa9Kk/xOQ== X-ME-Sender: Received: from dave.aj.id.au (220-253-52-107.dyn.iinet.net.au [220.253.52.107]) by mail.messagingengine.com (Postfix) with ESMTPA id 0FF1B240F8; Fri, 17 Nov 2017 22:26:55 -0500 (EST) From: Andrew Jeffery To: linux-hwmon@vger.kernel.org Cc: Andrew Jeffery , linux@roeck-us.net, robh+dt@kernel.org, mark.rutland@arm.com, 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 v5 4/4] pmbus (max31785): Add dual tachometer support Date: Sat, 18 Nov 2017 13:56:06 +1030 Message-Id: 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 dual tachometer feature is implemented in hardware with a TACHSEL input to indicate the rotor under measurement, and exposed on the device by extending the READ_FAN_SPEED_1 word with two extra bytes*. The need to read the non-standard four-byte response leads to a cut-down implementation of i2c_smbus_xfer_emulated() included in the driver. Further, to expose the second rotor tachometer value to userspace the values are exposed through virtual pages. We re-route accesses to FAN_CONFIG_1_2 and READ_FAN_SPEED_1 on pages 23-28 (not defined by the hardware) to the same registers on pages 0-5, and with the latter command we extract the value from the second word of the four-byte response. * The documentation recommends the slower rotor be associated with TACHSEL=0, which corresponds to the first word of the response. The TACHSEL=0 measurement is used by the controller's closed-loop fan management to judge target fan rate. Signed-off-by: Andrew Jeffery --- Documentation/hwmon/max31785 | 8 +- drivers/hwmon/pmbus/max31785.c | 147 ++++++++++++++++++++++++++++++++++- 2 files changed, 152 insertions(+), 3 deletions(-) diff --git a/Documentation/hwmon/max31785 b/Documentation/hwmon/max31785 index 7b0a0a8cdb6b..270c5f865261 100644 --- a/Documentation/hwmon/max31785 +++ b/Documentation/hwmon/max31785 @@ -17,8 +17,9 @@ management with temperature and remote voltage sensing. Various fan control features are provided, including PWM frequency control, temperature hysteresis, dual tachometer measurements, and fan health monitoring. -For dual rotor fan configuration, the MAX31785 exposes the slowest rotor of the -two in the fan[1-4]_input attributes. +For dual-rotor configurations the MAX31785A exposes the second rotor tachometer +readings in attributes fan[5-8]_input. By contrast the MAX31785 only exposes +the slowest rotor measurement, and does so in the fan[1-4]_input attributes. Usage Notes ----------- @@ -31,7 +32,8 @@ Sysfs attributes fan[1-4]_alarm Fan alarm. fan[1-4]_fault Fan fault. -fan[1-4]_input Fan RPM. +fan[1-8]_input Fan RPM. On the MAX31785A, inputs 5-8 correspond to the + second rotor of fans 1-4 fan[1-4]_target Fan input target in[1-6]_crit Critical maximum output voltage diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c index 2699134dfbe7..b5389070ae06 100644 --- a/drivers/hwmon/pmbus/max31785.c +++ b/drivers/hwmon/pmbus/max31785.c @@ -16,9 +16,79 @@ enum max31785_regs { MFR_REVISION = 0x9b, + MFR_FAN_CONFIG = 0xf1, }; +#define MAX31785 0x3030 +#define MAX31785A 0x3040 + +#define MFR_FAN_CONFIG_DUAL_TACH BIT(12) + #define MAX31785_NR_PAGES 23 +#define MAX31785_NR_FAN_PAGES 6 + +static int max31785_read_byte_data(struct i2c_client *client, int page, + int reg) +{ + if (page < MAX31785_NR_PAGES) + return -ENODATA; + + switch (reg) { + case PMBUS_VOUT_MODE: + return -ENOTSUPP; + case PMBUS_FAN_CONFIG_12: + return pmbus_read_byte_data(client, page - MAX31785_NR_PAGES, + reg); + } + + return -ENODATA; +} + +static int max31785_write_byte(struct i2c_client *client, int page, u8 value) +{ + if (page < MAX31785_NR_PAGES) + return -ENODATA; + + return -ENOTSUPP; +} + +static int max31785_read_long_data(struct i2c_client *client, int page, + int reg, u32 *data) +{ + unsigned char cmdbuf[1]; + unsigned char rspbuf[4]; + int rc; + + struct i2c_msg msg[2] = { + { + .addr = client->addr, + .flags = 0, + .len = sizeof(cmdbuf), + .buf = cmdbuf, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = sizeof(rspbuf), + .buf = rspbuf, + }, + }; + + cmdbuf[0] = reg; + + rc = pmbus_set_page(client, page); + if (rc < 0) + return rc; + + rc = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + if (rc < 0) + return rc; + + *data = (rspbuf[0] << (0 * 8)) | (rspbuf[1] << (1 * 8)) | + (rspbuf[2] << (2 * 8)) | (rspbuf[3] << (3 * 8)); + + return rc; +} static int max31785_get_pwm(struct i2c_client *client, int page) { @@ -62,9 +132,30 @@ static int max31785_get_pwm_mode(struct i2c_client *client, int page) static int max31785_read_word_data(struct i2c_client *client, int page, int reg) { + u32 val; int rv; switch (reg) { + case PMBUS_READ_FAN_SPEED_1: + if (page < MAX31785_NR_PAGES) + return -ENODATA; + + rv = max31785_read_long_data(client, page - MAX31785_NR_PAGES, + reg, &val); + if (rv < 0) + return rv; + + rv = (val >> 16) & 0xffff; + break; + case PMBUS_FAN_COMMAND_1: + /* + * PMBUS_FAN_COMMAND_x is probed to judge whether or not to + * expose fan control registers. + * + * Don't expose fan_target attribute for virtual pages. + */ + rv = (page >= MAX31785_NR_PAGES) ? -ENOTSUPP : -ENODATA; + break; case PMBUS_VIRT_PWM_1: rv = max31785_get_pwm(client, page); break; @@ -157,11 +248,15 @@ static int max31785_write_word_data(struct i2c_client *client, int page, #define MAX31785_VOUT_FUNCS \ (PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT) +#define MAX37185_NUM_FAN_PAGES 6 + static const struct pmbus_driver_info max31785_info = { .pages = MAX31785_NR_PAGES, .write_word_data = max31785_write_word_data, + .read_byte_data = max31785_read_byte_data, .read_word_data = max31785_read_word_data, + .write_byte = max31785_write_byte, /* RPM */ .format[PSC_FAN] = direct, @@ -208,13 +303,46 @@ static const struct pmbus_driver_info max31785_info = { .func[22] = MAX31785_VOUT_FUNCS, }; +static int max31785_configure_dual_tach(struct i2c_client *client, + struct pmbus_driver_info *info) +{ + int ret; + int i; + + for (i = 0; i < MAX31785_NR_FAN_PAGES; i++) { + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); + if (ret < 0) + return ret; + + ret = i2c_smbus_read_word_data(client, MFR_FAN_CONFIG); + if (ret < 0) + return ret; + + if (ret & MFR_FAN_CONFIG_DUAL_TACH) { + int virtual = MAX31785_NR_PAGES + i; + + info->pages = virtual + 1; + info->func[virtual] |= PMBUS_HAVE_FAN12; + info->func[virtual] |= PMBUS_PAGE_VIRTUAL; + } + } + + return 0; +} + static int max31785_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; struct pmbus_driver_info *info; + bool dual_tach = false; s64 ret; + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + info = devm_kzalloc(dev, sizeof(struct pmbus_driver_info), GFP_KERNEL); if (!info) return -ENOMEM; @@ -225,6 +353,25 @@ static int max31785_probe(struct i2c_client *client, if (ret < 0) return ret; + ret = i2c_smbus_read_word_data(client, MFR_REVISION); + if (ret < 0) + return ret; + + if (ret == MAX31785A) { + dual_tach = true; + } else if (ret == MAX31785) { + if (!strcmp("max31785a", id->name)) + dev_warn(dev, "Expected max3175a, found max31785: cannot provide secondary tachometer readings\n"); + } else { + return -ENODEV; + } + + if (dual_tach) { + ret = max31785_configure_dual_tach(client, info); + if (ret < 0) + return ret; + } + return pmbus_do_probe(client, id, info); }