From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELtzeZ8Fyi5AheiAyponjNySQ+aaqxov8IuD5GLxCAEYKqQdA+9pyl57lGyDyS+BSP1CeDvG ARC-Seal: i=1; a=rsa-sha256; t=1521607321; cv=none; d=google.com; s=arc-20160816; b=STaQVWk9ampYbUU+4RloCJpKVOh10yTjJ8mJKXbyeG0NCdIIDblJvRBxp92I2NQ5Ec h7gZwHgsmuOKTO7J0NGsDAtN6H7W6joE0Wknw8keDmfzVJnPLMHYKvYXlYadBi5HcPlT ZchEXacNMz9Gh3Leqw2kCI3rEDIoFFXzVoudGcNJ9Yap48aZ0BnsR8B1DUFphdq8rrht Oap+reSReiFOIEArmXRnnwWODhCLD+Fg2zoDFPluHUE5prnow76zGQgo/DqPoFUsmbK3 MKIZYlmdfDQmf+lQwU7ZlImLZAZ7YZ6rXGdBOYC2TsCTqw6zExFQ9/b+jOy/AJokTHmt m+4g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:references:in-reply-to:message-id:date:subject:cc:to :from:arc-authentication-results; bh=KnTZzAErrOzRoDAR19m+1MHotTDRmvjnqm0vVUPi+o4=; b=rkRg+SlEYwqlMbTWSRI/BSdwFIcSwItr18kuwAUAzxiIdGi8/ZfApMSZWrcT1coL/C q6MUuitHoiSMlOoSTwlfcH87QLQlAJ+1hC6RT5RnvAwxvcwJy3kFrIJpwTQfU2plwJRu aUjvLvob+pB+AoTNDRmrFIBSU1Nr3x5w5lqNlhc/duQzImxhvFYUo0mF5oPOpeBBB3sQ JzwDr6yxjltuA8qRgyYRpC3ia9tGHdMN/muoTw6mN5vWrMJdihIjn5REAfmbofDTvrP0 +DUGBGLymyr6sPDOjFodvXTQOtzJbO4tOMgCo7n2rJiKIdBmKwrpk62JV7o3LLUC6Y5/ zLNQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of rrajk@nvidia.com designates 216.228.121.143 as permitted sender) smtp.mailfrom=rrajk@nvidia.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nvidia.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of rrajk@nvidia.com designates 216.228.121.143 as permitted sender) smtp.mailfrom=rrajk@nvidia.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=nvidia.com X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 20 Mar 2018 21:42:00 -0700 From: Rajkumar Rampelli To: , , , , , , , , , , , , , , , , , , , , , CC: , , , , , , , , Subject: [PATCH V2 7/9] hwmon: pwm-fan: add sysfs node to read rpm of fan Date: Wed, 21 Mar 2018 10:10:42 +0530 Message-ID: <1521607244-29734-8-git-send-email-rrajk@nvidia.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1521607244-29734-1-git-send-email-rrajk@nvidia.com> References: <1521607244-29734-1-git-send-email-rrajk@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1595520919303322117?= X-GMAIL-MSGID: =?utf-8?q?1595520919303322117?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: Add fan device attribute fan1_input in pwm-fan driver to read speed of fan in rotations per minute. Signed-off-by: Rajkumar Rampelli --- V2: Removed generic-pwm-tachometer driver and using pwm-fan driver as per suggestions to read fan speed. Added fan device attribute to report speed of fan in rpms through hwmon sysfs. drivers/hwmon/pwm-fan.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c index 70cc0d1..8dda209 100644 --- a/drivers/hwmon/pwm-fan.c +++ b/drivers/hwmon/pwm-fan.c @@ -98,11 +98,34 @@ static ssize_t show_pwm(struct device *dev, return sprintf(buf, "%u\n", ctx->pwm_value); } +static ssize_t show_rpm(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct pwm_fan_ctx *ptt = dev_get_drvdata(dev); + struct pwm_device *pwm = ptt->pwm; + struct pwm_capture result; + unsigned int rpm = 0; + int ret; + + ret = pwm_capture(pwm, &result, 0); + if (ret < 0) { + pr_err("Failed to capture PWM: %d\n", ret); + return ret; + } + + if (result.period) + rpm = DIV_ROUND_CLOSEST_ULL(60ULL * NSEC_PER_SEC, + result.period); + + return sprintf(buf, "%u\n", rpm); +} static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO | S_IWUSR, show_pwm, set_pwm, 0); +static SENSOR_DEVICE_ATTR(fan1_input, 0444, show_rpm, NULL, 0); static struct attribute *pwm_fan_attrs[] = { &sensor_dev_attr_pwm1.dev_attr.attr, + &sensor_dev_attr_fan1_input.dev_attr.attr, NULL, }; -- 2.1.4