From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 E3897C47255 for ; Mon, 11 May 2020 20:38:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA17820752 for ; Mon, 11 May 2020 20:38:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="ZJEAE5y7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731793AbgEKUiP (ORCPT ); Mon, 11 May 2020 16:38:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731642AbgEKUiO (ORCPT ); Mon, 11 May 2020 16:38:14 -0400 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4082DC061A0C for ; Mon, 11 May 2020 13:38:14 -0700 (PDT) Received: by mail-wr1-x442.google.com with SMTP id y16so5508410wrs.3 for ; Mon, 11 May 2020 13:38:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Hh5tRfp8hFoQbtcLOPwI0yX1TWzzDo4g9zDKAm7iihs=; b=ZJEAE5y7La4UsaMGKf9uQF9t1sOoWlDU6FWn2RKOnzgGOxfb6avGVZOhYH/Q7b8gjw wAcT/eRKTG+v50WX7NPueMTeA+1ZqnOzraYAkfJTXtXL5wGwWOUUaDdHOyQcv4cJJTRw TuxLvQi6DeJevbS048Ig3kUL9SPBX4X4eH7w/IzztMblBet8XR4nXa4vznSPS/yHL4F2 gMYRWBGtllohpATfAeezigq3phrYn8ggSGWrU9xj4Ge4pXCVsok6vNLimzFc5ZX1tRuZ oK0+Ll7Mxacl1E7NhpT2dfwjYZ7pZ0IP1oEOaL7B5qGujVxh2dZOYtgm3cKQ0ReKz9PQ dZSg== 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:mime-version :content-transfer-encoding; bh=Hh5tRfp8hFoQbtcLOPwI0yX1TWzzDo4g9zDKAm7iihs=; b=AE1ykgDbpum7L2ed2ShcqPRCZ8uVQvGhFVlPuNkeW1eAL/gXGy/K0nkNqhczV/d82c bpYc8u8e/83tnQi2l0PM3h6n22XDUtkuMW/PzJvydlr2DbcHWK4WsCJor9/JOzMPoviy p0V2aqQ6oTNsye6+L15uPjBfqtsp1VD3gCD7D+dTkC2vbmOUNu8O7fzxtiJk3rIm2IBJ EP3V8IlagxWzt+f2sWz24qj6orLwSSbGIEVi1Tn/xCxGW5xckqGQdxU21xhz371v5miG 8pwDHoSIt7YKeTyaNymfQ0bNgYGfdVRnqg4zFUb7JI+nUsn3nEnAMZPUNOZyrhgAtFo5 8PtQ== X-Gm-Message-State: AGi0PuY7Ney7gHctLvsrb21OWl5XFzU/FEfcaWpihYRAVq5WaX0alJx9 7whCxOmKKGLk60GWW890hPY= X-Google-Smtp-Source: APiQypIINkNkOPrhfNt1Qo2N4ScwQj3cOu/w1QAdksjjnqOkEgKISjpsh3+r9dZtI+kXROg7W1YumA== X-Received: by 2002:adf:dc89:: with SMTP id r9mr19734235wrj.138.1589229492859; Mon, 11 May 2020 13:38:12 -0700 (PDT) Received: from akira-laptop.home ([2a01:cb19:8b28:7600:a0b9:1c6f:cfba:2b21]) by smtp.googlemail.com with ESMTPSA id n24sm11914959wmi.40.2020.05.11.13.38.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 May 2020 13:38:12 -0700 (PDT) From: Akira Shimahara To: greg@kroah.com, rdunlap@infradead.org Cc: zbr@ioremap.net, linux-kernel@vger.kernel.org, Akira Shimahara Subject: [PATCH v7 8/9] w1_therm: adding alarm sysfs entry Date: Mon, 11 May 2020 22:38:01 +0200 Message-Id: <20200511203801.411253-1-akira215corp@gmail.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Adding device alarms settings by a dedicated sysfs entry alarms (RW): read or write TH and TL in the device RAM. Checking devices in alarm state could be performed using the master search command. As alarms temperature level are store in a 8 bit register on the device and are signed values, a safe cast shall be performed using the min and max temperature that device are able to measure. This is done by int_to_short inline function. A 'write_data' field is added in the device structure, to bind the correct writing function, as some devices may have 2 or 3 bytes RAM. Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara --- Changes in v5: - All patch serie in one .c file - Correcting some comments - adding include Changes in v6: - Formatting code comments according to kernel-doc requirements Changes in v7: - Formatting code comments and correcting comments mistakes .../ABI/testing/sysfs-driver-w1_therm | 16 ++ drivers/w1/slaves/w1_therm.c | 161 ++++++++++++++++++ 2 files changed, 177 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-driver-w1_therm b/Documentation/ABI/testing/sysfs-driver-w1_therm index 6ffd3e3..f289520 100644 --- a/Documentation/ABI/testing/sysfs-driver-w1_therm +++ b/Documentation/ABI/testing/sysfs-driver-w1_therm @@ -1,3 +1,19 @@ +What: /sys/bus/w1/devices/.../alarms +Date: May 2020 +Contact: Akira Shimahara +Description: + (RW) read or write TH and TL (Temperature High an Low) alarms. + Values shall be space separated and in the device range + (typical -55 degC to 125 degC), if not values will be trimmed + to device min/max capabilities. Values are integer as they are + stored in a 8bit register in the device. Lowest value is + automatically put to TL. Once set, alarms could be search at + master level, refer to Documentation/w1/w1_generic.rst for + detailed information +Users: any user space application which wants to communicate with + w1_term device + + What: /sys/bus/w1/devices/.../eeprom Date: May 2020 Contact: Akira Shimahara diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c index 46756ea..fac9908 100644 --- a/drivers/w1/slaves/w1_therm.c +++ b/drivers/w1/slaves/w1_therm.c @@ -58,6 +58,9 @@ module_param_named(strong_pullup, w1_strong_pullup, int, 0); #define EEPROM_CMD_WRITE "save" /* cmd for write eeprom sysfs */ #define EEPROM_CMD_READ "restore" /* cmd for read eeprom sysfs */ +#define MIN_TEMP -55 /* min temperature that can be mesured */ +#define MAX_TEMP 125 /* max temperature that can be mesured */ + /* Helpers Macros */ /* @@ -96,6 +99,7 @@ module_param_named(strong_pullup, w1_strong_pullup, int, 0); * @get_conversion_time: pointer to the device conversion time function * @set_resolution: pointer to the device set_resolution function * @get_resolution: pointer to the device get_resolution function + * @write_data: pointer to the device writing function (2 or 3 bytes) */ struct w1_therm_family_converter { u8 broken; @@ -105,6 +109,7 @@ struct w1_therm_family_converter { int (*get_conversion_time)(struct w1_slave *sl); int (*set_resolution)(struct w1_slave *sl, int val); int (*get_resolution)(struct w1_slave *sl); + int (*write_data)(struct w1_slave *sl, const u8 *data); }; /** @@ -239,6 +244,12 @@ static ssize_t resolution_store(struct device *device, static ssize_t eeprom_store(struct device *device, struct device_attribute *attr, const char *buf, size_t size); +static ssize_t alarms_store(struct device *device, + struct device_attribute *attr, const char *buf, size_t size); + +static ssize_t alarms_show(struct device *device, + struct device_attribute *attr, char *buf); + /* Attributes declarations */ static DEVICE_ATTR_RW(w1_slave); @@ -247,6 +258,7 @@ static DEVICE_ATTR_RO(temperature); static DEVICE_ATTR_RO(ext_power); static DEVICE_ATTR_RW(resolution); static DEVICE_ATTR_WO(eeprom); +static DEVICE_ATTR_RW(alarms); /* Interface Functions declaration */ @@ -278,6 +290,7 @@ static struct attribute *w1_therm_attrs[] = { &dev_attr_ext_power.attr, &dev_attr_resolution.attr, &dev_attr_eeprom.attr, + &dev_attr_alarms.attr, NULL, }; @@ -286,6 +299,7 @@ static struct attribute *w1_ds18s20_attrs[] = { &dev_attr_temperature.attr, &dev_attr_ext_power.attr, &dev_attr_eeprom.attr, + &dev_attr_alarms.attr, NULL, }; @@ -296,6 +310,7 @@ static struct attribute *w1_ds28ea00_attrs[] = { &dev_attr_ext_power.attr, &dev_attr_resolution.attr, &dev_attr_eeprom.attr, + &dev_attr_alarms.attr, NULL, }; @@ -556,6 +571,7 @@ static struct w1_therm_family_converter w1_therm_families[] = { .get_conversion_time = w1_DS18S20_convert_time, .set_resolution = NULL, /* no config register */ .get_resolution = NULL, /* no config register */ + .write_data = w1_DS18S20_write_data, }, { .f = &w1_therm_family_DS1822, @@ -563,6 +579,7 @@ static struct w1_therm_family_converter w1_therm_families[] = { .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, + .write_data = w1_DS18B20_write_data, }, { .f = &w1_therm_family_DS18B20, @@ -570,6 +587,7 @@ static struct w1_therm_family_converter w1_therm_families[] = { .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, + .write_data = w1_DS18B20_write_data, }, { .f = &w1_therm_family_DS28EA00, @@ -577,6 +595,7 @@ static struct w1_therm_family_converter w1_therm_families[] = { .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, + .write_data = w1_DS18B20_write_data, }, { .f = &w1_therm_family_DS1825, @@ -584,6 +603,7 @@ static struct w1_therm_family_converter w1_therm_families[] = { .get_conversion_time = w1_DS18B20_convert_time, .set_resolution = w1_DS18B20_set_resolution, .get_resolution = w1_DS18B20_get_resolution, + .write_data = w1_DS18B20_write_data, } }; @@ -678,6 +698,26 @@ static inline int temperature_from_RAM(struct w1_slave *sl, u8 rom[9]) return 0; /* No device family */ } +/** + * int_to_short() - Safe casting of int to short + * + * @i: integer to be converted to short + * + * Device register use 1 byte to store signed integer. + * This helper function convert the int in a signed short, + * using the min/max values that device can measure as limits. + * min/max values are defined by macro. + * + * Return: a short in the range of min/max value + */ +static inline s8 int_to_short(int i) +{ + /* Prepare to cast to short by eliminating out of range values */ + i = i > MAX_TEMP ? MAX_TEMP : i; + i = i < MIN_TEMP ? MIN_TEMP : i; + return (s8) i; +} + /* Interface Functions */ static int w1_therm_add_slave(struct w1_slave *sl) @@ -1251,6 +1291,127 @@ static ssize_t eeprom_store(struct device *device, return size; } +static ssize_t alarms_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + int ret = -ENODEV; + s8 th = 0, tl = 0; + struct therm_info scratchpad; + + ret = read_scratchpad(sl, &scratchpad); + + if (!ret) { + th = scratchpad.rom[2]; /* TH is byte 2 */ + tl = scratchpad.rom[3]; /* TL is byte 3 */ + } else { + dev_info(device, + "%s: error reading alarms register %d\n", + __func__, ret); + } + + return sprintf(buf, "%hd %hd\n", tl, th); +} + +static ssize_t alarms_store(struct device *device, + struct device_attribute *attr, const char *buf, size_t size) +{ + struct w1_slave *sl = dev_to_w1_slave(device); + struct therm_info info; + u8 new_config_register[3]; /* array of data to be written */ + int temp, ret = -EINVAL; + char *token = NULL; + s8 tl, th, tt; /* 1 byte per value + temp ring order */ + char *p_args = kmalloc(size, GFP_KERNEL); + + /* Safe string copys as buf is const */ + if (!p_args) { + dev_warn(device, + "%s: error unable to allocate memory %d\n", + __func__, -ENOMEM); + return size; + } + strcpy(p_args, buf); + + /* Split string using space char */ + token = strsep(&p_args, " "); + + if (!token) { + dev_info(device, + "%s: error parsing args %d\n", __func__, -EINVAL); + goto free_m; + } + + /* Convert 1st entry to int */ + ret = kstrtoint (token, 10, &temp); + if (ret) { + dev_info(device, + "%s: error parsing args %d\n", __func__, ret); + goto free_m; + } + + tl = int_to_short(temp); + + /* Split string using space char */ + token = strsep(&p_args, " "); + if (!token) { + dev_info(device, + "%s: error parsing args %d\n", __func__, -EINVAL); + goto free_m; + } + /* Convert 2nd entry to int */ + ret = kstrtoint (token, 10, &temp); + if (ret) { + dev_info(device, + "%s: error parsing args %d\n", __func__, ret); + goto free_m; + } + + /* Prepare to cast to short by eliminating out of range values */ + th = int_to_short(temp); + + /* Reorder if required th and tl */ + if (tl > th) { + tt = tl; tl = th; th = tt; + } + + /* + * Read the scratchpad to change only the required bits + * (th : byte 2 - tl: byte 3) + */ + ret = read_scratchpad(sl, &info); + if (!ret) { + new_config_register[0] = th; /* Byte 2 */ + new_config_register[1] = tl; /* Byte 3 */ + new_config_register[2] = info.rom[4];/* Byte 4 */ + } else { + dev_info(device, + "%s: error reading from the slave device %d\n", + __func__, ret); + goto free_m; + } + + /* Write data in the device RAM */ + if (!SLAVE_SPECIFIC_FUNC(sl)) { + dev_info(device, + "%s: Device not supported by the driver %d\n", + __func__, -ENODEV); + goto free_m; + } + + ret = SLAVE_SPECIFIC_FUNC(sl)->write_data(sl, new_config_register); + if (ret) + dev_info(device, + "%s: error writing to the slave device %d\n", + __func__, ret); + +free_m: + /* free allocated memory */ + kfree(p_args); + + return size; +} + #if IS_REACHABLE(CONFIG_HWMON) static int w1_read_temp(struct device *device, u32 attr, int channel, long *val) -- 2.26.2