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[2001:1868:205::9]) by mx.google.com with ESMTPS id x69si19547463pfi.210.2016.02.19.16.11.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 19 Feb 2016 16:11:30 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) client-ip=2001:1868:205::9; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org designates 2001:1868:205::9 as permitted sender) smtp.mailfrom=linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1aWv7u-0000zz-W0; Sat, 20 Feb 2016 00:10:23 +0000 Received: from bear.ext.ti.com ([192.94.94.41]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1aWv7s-0008AV-38 for linux-arm-kernel@lists.infradead.org; Sat, 20 Feb 2016 00:10:21 +0000 Received: from dlelxv90.itg.ti.com ([172.17.2.17]) by bear.ext.ti.com (8.13.7/8.13.7) with ESMTP id u1K09tVw019585; Fri, 19 Feb 2016 18:09:55 -0600 Received: from DLEE71.ent.ti.com (dlee71.ent.ti.com [157.170.170.114]) by dlelxv90.itg.ti.com (8.14.3/8.13.8) with ESMTP id u1K09tUZ002868; Fri, 19 Feb 2016 18:09:55 -0600 Received: from dflp33.itg.ti.com (10.64.6.16) by DLEE71.ent.ti.com (157.170.170.114) with Microsoft SMTP Server id 14.3.224.2; Fri, 19 Feb 2016 18:09:54 -0600 Received: from localhost (ileax41-snat.itg.ti.com [10.172.224.153]) by dflp33.itg.ti.com (8.14.3/8.13.8) with ESMTP id u1K09sF5012458; Fri, 19 Feb 2016 18:09:54 -0600 From: Nishanth Menon To: Guenter Roeck , Jean Delvare Subject: [PATCH] hwmon: (gpio-fan) Remove un-necessary speed_index lookup for thermal hook Date: Fri, 19 Feb 2016 18:09:51 -0600 Message-ID: <1455926991-15189-1-git-send-email-nm@ti.com> X-Mailer: git-send-email 1.7.9.5 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160219_161020_254669_C6710DC1 X-CRM114-Status: GOOD ( 10.39 ) X-Spam-Score: -6.9 (------) X-Spam-Report: SpamAssassin version 3.4.0 on bombadil.infradead.org summary: Content analysis details: (-6.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [192.94.94.41 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nishanth Menon , Tony Lindgren , linux-kernel@vger.kernel.org, lm-sensors@lm-sensors.org, Eduardo Valentin , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patch=linaro.org@lists.infradead.org Thermal hook gpio_fan_get_cur_state is only interested in knowing the current speed index that was setup in the system, this is already available as part of fan_data->speed_index which is always set by set_fan_speed. Using get_fan_speed_index is useful when we have no idea about the fan speed configuration (for example during fan_ctrl_init). When thermal framework invokes gpio_fan_get_cur_state=>get_fan_speed_index via gpio_fan_get_cur_state especially in a polled configuration for thermal governor, we basically hog the i2c interface to the extent that other functions fail to get any traffic out :(. Instead, just provide the last state set in the driver - since the gpio fan driver is responsible for the fan state immaterial of override, the fan_data->speed_index should accurately reflect the state. Fixes: b5cf88e46bad ("(gpio-fan): Add thermal control hooks") Reported-by: Tony Lindgren Cc: Guenter Roeck Cc: Eduardo Valentin Signed-off-by: Nishanth Menon --- Test logs from linus master v4.5-rc4-137-g23300f657594 Without fix: http://paste.ubuntu.org.cn/3948618 With Fix: http://paste.ubuntu.org.cn/3948617 drivers/hwmon/gpio-fan.c | 7 +------ 1 file changed, 1 insertion(+), 6 deletions(-) -- 2.7.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel diff --git a/drivers/hwmon/gpio-fan.c b/drivers/hwmon/gpio-fan.c index 82de3deeb18a..685568b1236d 100644 --- a/drivers/hwmon/gpio-fan.c +++ b/drivers/hwmon/gpio-fan.c @@ -406,16 +406,11 @@ static int gpio_fan_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state) { struct gpio_fan_data *fan_data = cdev->devdata; - int r; if (!fan_data) return -EINVAL; - r = get_fan_speed_index(fan_data); - if (r < 0) - return r; - - *state = r; + *state = fan_data->speed_index; return 0; }