From patchwork Wed Nov 20 14:47:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrea Merello X-Patchwork-Id: 11254049 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BAE3A138C for ; Wed, 20 Nov 2019 14:49:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 92423206DA for ; Wed, 20 Nov 2019 14:49:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="DnJ6Im0F" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731420AbfKTOtb (ORCPT ); Wed, 20 Nov 2019 09:49:31 -0500 Received: from mail-wm1-f67.google.com ([209.85.128.67]:34339 "EHLO mail-wm1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729932AbfKTOta (ORCPT ); Wed, 20 Nov 2019 09:49:30 -0500 Received: by mail-wm1-f67.google.com with SMTP id j18so5313487wmk.1; Wed, 20 Nov 2019 06:49:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=SDuzEyv/KU+kJTNU1MX2E+5z7wOJJryFHRQ9Hq8mD28=; b=DnJ6Im0FBkpkZPNRyob5Ja80ztK3k856m/CzwrivEYu6buCuhr+3w355OTjfUh+tqZ 5zAXoP7cw4QQuQA+xGFT9/Oh7uEorR9AgYPwCggnAnsousz2iItPrb/wFYP6LXoTqFJC FF2bB1l4smmocRqTjqMDFY+MxNiHzUhKXpoAbeDxPmtL1+545dKK56CTd0lNPYyeyMd1 Q+SMB+U/rkqkPi+G54pSsS/pON79yMqru9KgIiEPrtxtPzUQzHSlz9pM5i8LRUp2+fH4 prt6aSFHlZouodQkfi4Wg+Pzk7BcwYhj/A9aXNkfRnVAaN+M7PP5NgkSUv8A+r4PqmpM TGHg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=SDuzEyv/KU+kJTNU1MX2E+5z7wOJJryFHRQ9Hq8mD28=; b=eKuN7ghSLKIJndOK2hxF3CfaLdwbT8lY/DIIAtHVWnVxF+WxqIAKLTuQPocMIrJ0Vw DVc59Wk9Ph3YJIW4E8dWP9qs4DIFXYXMM5Bky9YvsRXxF+KIhTJc14tfGYdjP2nA7jEB olQWSYahdQgXzdns+B/oXD+8pAxUWWaeZP8gpPY5eZHwE8scJqQx0Y/L/5dRd8z+xLiE KEl1VpAlAf+0EtMXuxm2BDUibs603sZCPH9V4paofwpgoQt1l0MPlbIaOA0Fia9Hzcrq iP1JntoioW3rqpG5IlZr7r9Ik2qV3V6NAFt6OSE8+yWzcV7TXNBjPVuu//YeR6cHBePN MEwg== X-Gm-Message-State: APjAAAXGRaolqlo4ZSXLhZxJp9zPcEfueYYfu6yGDqyVFCxPiE7/XD7r itWmGuAg2BkhJo3TeixjoB0= X-Google-Smtp-Source: APXvYqy0i3WR9TvovXLASrOVv3UvaEW75ldDidda6jDKdLEyXXCVJTLDRoWBFl0dStR3RGRRTEgOdA== X-Received: by 2002:a05:600c:2549:: with SMTP id e9mr3558941wma.177.1574261367586; Wed, 20 Nov 2019 06:49:27 -0800 (PST) Received: from NewMoon.iit.local ([90.147.180.254]) by smtp.gmail.com with ESMTPSA id b2sm5822120wrr.76.2019.11.20.06.49.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Nov 2019 06:49:26 -0800 (PST) From: Andrea Merello To: jic23@kernel.org Cc: Andrea Merello , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , Colin Ian King , Patrick Havelange , Matt Weber , Matt Ranostay , Chuhong Yuan , Daniel Gomez , linux-iio@vger.kernel.org, Rob Herring , Mark Rutland , devicetree@vger.kernel.org Subject: [v3 8/9] RFC/RFT: iio: maxim_thermocouple: add thermocouple_type sysfs attribute Date: Wed, 20 Nov 2019 15:47:55 +0100 Message-Id: <20191120144756.28424-9-andrea.merello@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20191120144756.28424-1-andrea.merello@gmail.com> References: <20191111153517.13862-1-andrea.merello@gmail.com> <20191120144756.28424-1-andrea.merello@gmail.com> Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org We added a sysfs ABI for getting/setting the type of a thermocouple. This driver supports chips that support specific fixed thermocouple types; we cannot set it, but still we can add this sysfs attribute in RO mode to read-back the thermocouple type. This driver supports actually several chips: - max6675 - max31855[k/j/n/s/t/e/r]asa family Max6675 supports only K-type thermocouples, so we can just report that. Each chip in max31855 family supports just one specific thermocouple type (in the obvious way: i.e. max31855jasa supports J-type). This driver did accept a generic SPI ID and OF compatible "max31855" which does not give any clue about which chip is really involved (and unfortunately it seems we have no way to detect it). This patch introduces a new set of, more specific, SPI IDs and OF compatible strings to better match the chip type. The old, generic, "max31855" binding is kept for compatibility reasons, but this patch aims to deprecate it, so, should we hit it, a warning is spit. In such case the reported thermocouple type in sysfs is '?', because we have no way to know. Regarding the implementation: the thermocouple type information is stored in the driver private data and I've kept only two maxim_thermocouple_chip types in order to avoid a lot of duplications (seven chip types with just a different thermocouple type). RFT because I have no real HW to test this. Cc: Hartmut Knaack Cc: Lars-Peter Clausen Cc: Peter Meerwald-Stadler Cc: Colin Ian King Cc: Patrick Havelange Cc: Matt Weber Cc: Matt Ranostay Cc: Chuhong Yuan Cc: Daniel Gomez Cc: linux-iio@vger.kernel.org Cc: Rob Herring Cc: Mark Rutland Cc: devicetree@vger.kernel.org Signed-off-by: Andrea Merello --- drivers/iio/temperature/maxim_thermocouple.c | 44 ++++++++++++++++++-- 1 file changed, 41 insertions(+), 3 deletions(-) diff --git a/drivers/iio/temperature/maxim_thermocouple.c b/drivers/iio/temperature/maxim_thermocouple.c index d1360605209c..9906b31fe863 100644 --- a/drivers/iio/temperature/maxim_thermocouple.c +++ b/drivers/iio/temperature/maxim_thermocouple.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -24,13 +25,25 @@ enum { MAX6675, MAX31855, + MAX31855K, + MAX31855J, + MAX31855N, + MAX31855S, + MAX31855T, + MAX31855E, + MAX31855R, +}; + +const char maxim_tc_types[] = { + 'K', '?', 'K', 'J', 'N', 'S', 'T', 'E', 'R' }; static const struct iio_chan_spec max6675_channels[] = { { /* thermocouple temperature */ .type = IIO_TEMP, .info_mask_separate = - BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_THERMOCOUPLE_TYPE), .scan_index = 0, .scan_type = { .sign = 's', @@ -48,7 +61,8 @@ static const struct iio_chan_spec max31855_channels[] = { .type = IIO_TEMP, .address = 2, .info_mask_separate = - BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE), + BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_THERMOCOUPLE_TYPE), .scan_index = 0, .scan_type = { .sign = 's', @@ -110,6 +124,7 @@ struct maxim_thermocouple_data { const struct maxim_thermocouple_chip *chip; u8 buffer[16] ____cacheline_aligned; + char tc_type; }; static int maxim_thermocouple_read(struct maxim_thermocouple_data *data, @@ -196,6 +211,10 @@ static int maxim_thermocouple_read_raw(struct iio_dev *indio_dev, ret = IIO_VAL_INT; } break; + case IIO_CHAN_INFO_THERMOCOUPLE_TYPE: + *val = data->tc_type; + ret = IIO_VAL_CHAR; + break; } return ret; @@ -210,8 +229,9 @@ static int maxim_thermocouple_probe(struct spi_device *spi) const struct spi_device_id *id = spi_get_device_id(spi); struct iio_dev *indio_dev; struct maxim_thermocouple_data *data; + const int chip_type = (id->driver_data == MAX6675) ? MAX6675 : MAX31855; const struct maxim_thermocouple_chip *chip = - &maxim_thermocouple_chips[id->driver_data]; + &maxim_thermocouple_chips[chip_type]; int ret; indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*data)); @@ -229,6 +249,7 @@ static int maxim_thermocouple_probe(struct spi_device *spi) data = iio_priv(indio_dev); data->spi = spi; data->chip = chip; + data->tc_type = maxim_tc_types[id->driver_data]; ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev, NULL, @@ -236,12 +257,22 @@ static int maxim_thermocouple_probe(struct spi_device *spi) if (ret) return ret; + if (id->driver_data == MAX31855) + dev_warn(&spi->dev, "generic max31855 ID is deprecated\nplease use more specific part type"); + return devm_iio_device_register(&spi->dev, indio_dev); } static const struct spi_device_id maxim_thermocouple_id[] = { {"max6675", MAX6675}, {"max31855", MAX31855}, + {"max31855k", MAX31855K}, + {"max31855j", MAX31855J}, + {"max31855n", MAX31855N}, + {"max31855s", MAX31855S}, + {"max31855t", MAX31855T}, + {"max31855e", MAX31855E}, + {"max31855r", MAX31855R}, {}, }; MODULE_DEVICE_TABLE(spi, maxim_thermocouple_id); @@ -249,6 +280,13 @@ MODULE_DEVICE_TABLE(spi, maxim_thermocouple_id); static const struct of_device_id maxim_thermocouple_of_match[] = { { .compatible = "maxim,max6675" }, { .compatible = "maxim,max31855" }, + { .compatible = "maxim,max31855k" }, + { .compatible = "maxim,max31855j" }, + { .compatible = "maxim,max31855n" }, + { .compatible = "maxim,max31855s" }, + { .compatible = "maxim,max31855t" }, + { .compatible = "maxim,max31855e" }, + { .compatible = "maxim,max31855r" }, { }, }; MODULE_DEVICE_TABLE(of, maxim_thermocouple_of_match);