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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 3FE2CC41604 for ; Tue, 6 Oct 2020 06:41:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D2BEC20796 for ; Tue, 6 Oct 2020 06:41:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=sartura-hr.20150623.gappssmtp.com header.i=@sartura-hr.20150623.gappssmtp.com header.b="F2Tik6j5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726769AbgJFGl5 (ORCPT ); Tue, 6 Oct 2020 02:41:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48206 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725962AbgJFGl5 (ORCPT ); Tue, 6 Oct 2020 02:41:57 -0400 Received: from mail-il1-x141.google.com (mail-il1-x141.google.com [IPv6:2607:f8b0:4864:20::141]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4F1F4C0613A7 for ; Mon, 5 Oct 2020 23:41:57 -0700 (PDT) Received: by mail-il1-x141.google.com with SMTP id q1so10051224ilt.6 for ; Mon, 05 Oct 2020 23:41:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sartura-hr.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=uHM1D8yaoPgVu7OkaALEGbJy4kg1o1eRhm5NyrRUylM=; b=F2Tik6j5lSqAx01VgPEc/ic+3a+2cD1ALsagm7/uTKd1bFTlXB0iPvJ6wLB5MMREgm cQFQECDIn+HmLqpvNq+6dM7W/vCKzNLNOk8FhCCoUoQ5HtaN1QmvZRAmOIx67g27vp8U dkXLOPpf9OkLw2ZTqn7JxwF3ktoTg4BcmFrl+HB5IasXlTK+GbxCc4aNY1oM3Cd2C2u3 IhDCLLQGMij02rtGUhH8uQOJIYa0gJ8cRtQSPgeHOIU7J3cNpBYvbzi9AVuqHFR6gpRI ab6mJlHu1WZwBiJk/UAduBwW8UjiuIckfS1QbPhdCsrbrKIvk23SboncRwXDNfRFlbdA u1Og== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=uHM1D8yaoPgVu7OkaALEGbJy4kg1o1eRhm5NyrRUylM=; b=qXvzaGk9CkU8NEw6fe7JsLTHanWzO/30NSRPzHMQT9RwWWMlwlj9fdV068hs7rElge kx9SAyE5U9b7OQdWgmFrr4OgDin08ExtwHQEBfYzyNzm17zeaqvtTHEKk5Tsy1dvXxqr JJ+BlkM6HCUlsberyAzITX8c0crEqf5mqISRePwOhHDG4xdeLTjjocXTDh3j798jRUKe Jo18timNugswHgEFRdbP5nAlbDfmWZD2i4dmmXE5OqyzT2exgBBfW/SeyWZemX/nbc/c 2+dVN7ullLxl/p9XUEx55suskjR5YOlBz1ks4zC3gTzK5/pqrpE8u5FMhgRZ8PbylYPk Ixmw== X-Gm-Message-State: AOAM530+JGB9Svla5b6TaFu8FuBKmz64hV4CwVgShS0UtSbjZ5SHu6zu GIK8L2Jo6BTMMjwHanJ8o/jF3j0nMtXF21VRi4Z6Zg== X-Google-Smtp-Source: ABdhPJwOFY2AVkq+DSviecXMqxbtuAa8qCx0Gyx56bAvbqU5sjiGaic0Dbg30kwuz9+gBlPKxjdMeoxiUgKTvZh1Evg= X-Received: by 2002:a92:c00c:: with SMTP id q12mr2436199ild.294.1601966516666; Mon, 05 Oct 2020 23:41:56 -0700 (PDT) MIME-Version: 1.0 References: <20200930014058.44460-1-luka.kovacic@sartura.hr> <20200930014058.44460-5-luka.kovacic@sartura.hr> <20200930194759.GA24378@amd> In-Reply-To: <20200930194759.GA24378@amd> From: Luka Kovacic Date: Tue, 6 Oct 2020 08:41:45 +0200 Message-ID: Subject: Re: [PATCH v3 4/7] drivers: leds: Add the iEi WT61P803 PUZZLE LED driver To: Pavel Machek Cc: Linux Kernel Mailing List , linux-hwmon@vger.kernel.org, linux-arm Mailing List , Linux LED Subsystem , Lee Jones , Dan Murphy , Rob Herring , Jean Delvare , Guenter Roeck , Andrew Lunn , Jason Cooper , Gregory Clement , Marek Behun , Luka Perkov , Robert Marko Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-hwmon@vger.kernel.org On Wed, Sep 30, 2020 at 9:48 PM Pavel Machek wrote: > > Hi! > > > +static int iei_wt61p803_puzzle_led_brightness_set_blocking(struct led_classdev *cdev, > > + enum led_brightness brightness) > > +{ > > + struct iei_wt61p803_puzzle_led *priv = cdev_to_iei_wt61p803_puzzle_led(cdev); > > + unsigned char *resp_buf = priv->response_buffer; > > + unsigned char led_power_cmd[5] = { > > + IEI_WT61P803_PUZZLE_CMD_HEADER_START, > > + IEI_WT61P803_PUZZLE_CMD_LED, > > + IEI_WT61P803_PUZZLE_CMD_LED_POWER, > > + (char)IEI_LED_OFF > > + }; > > + size_t reply_size; > > + > > + mutex_lock(&priv->lock); > > + if (brightness == LED_OFF) { > > + led_power_cmd[3] = (char)IEI_LED_OFF; > > + priv->led_power_state = LED_OFF; > > + } else { > > + led_power_cmd[3] = (char)IEI_LED_ON; > > + priv->led_power_state = LED_ON; > > + } > > + mutex_unlock(&priv->lock); > > + > > + return iei_wt61p803_puzzle_write_command(priv->mcu, led_power_cmd, > > + sizeof(led_power_cmd), resp_buf, &reply_size); > > +} > > Is the mutex needed? If so, should it include the > iei_wt61p803_puzzle_write_command()? Does > iei_wt61p803_puzzle_write_command() have internal locking to prevent > two messages from being mingled? > > Best regards, > Pavel > > -- > (english) http://www.livejournal.com/~pavelmachek > (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html Hello Pavel, The mutex isn't needed and can be removed. The function iei_wt61p803_puzzle_write_command() already handles its own mutex locking, so a separate mutex isn't required. Does brightness_set_blocking only block a single caller (each caller separately) or does it block all callers until the previous caller is finished? Kind regards, Luka 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=-4.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 A2A80C41604 for ; Tue, 6 Oct 2020 06:43:31 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 23DAF20757 for ; Tue, 6 Oct 2020 06:43:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="EkWO4xYX"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=sartura-hr.20150623.gappssmtp.com header.i=@sartura-hr.20150623.gappssmtp.com header.b="F2Tik6j5" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 23DAF20757 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=sartura.hr Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:To:Subject:Message-ID:Date:From:In-Reply-To: References:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=wFGETNv1/cEev2he9S9rRtuk97HdFhfDv3wFNmTcMx0=; b=EkWO4xYXpLEjZ3wFDsRXhmVo1 cxIYkW8pSaSI5AI4o/ug9h1nU80xT1AZCoKXGK+ZK5g0DAtG3orvbIRdPLhHvuXQH9ZchxPG9nP6k C/rgIwmDBdMx+A9S2bnKWoyPz+u9J4YSj26vkusHZKmLVpVKR9dWp0vGdzPpMar3MCRiPdSIdECGR 0oLdoSfd3CaBjk6vcmIjKD2PhL5WM/PgnRRqs33Kt5evAI2SjnqmH6W1R0TdWKq8+3dYjJSn2W7OL Lldvsew/oj9j/qLwFsb9k3+nKLQmbxSbRiuFVs8jc1hJyXZ1aZv2Vsm/cBX7hIRippQ1ppsmSjIbY ewL0wI46w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kPgfi-0001Mb-6q; Tue, 06 Oct 2020 06:42:02 +0000 Received: from mail-il1-x143.google.com ([2607:f8b0:4864:20::143]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kPgfg-0001Lh-9u for linux-arm-kernel@lists.infradead.org; Tue, 06 Oct 2020 06:42:01 +0000 Received: by mail-il1-x143.google.com with SMTP id d66so373282ill.0 for ; Mon, 05 Oct 2020 23:41:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sartura-hr.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=uHM1D8yaoPgVu7OkaALEGbJy4kg1o1eRhm5NyrRUylM=; b=F2Tik6j5lSqAx01VgPEc/ic+3a+2cD1ALsagm7/uTKd1bFTlXB0iPvJ6wLB5MMREgm cQFQECDIn+HmLqpvNq+6dM7W/vCKzNLNOk8FhCCoUoQ5HtaN1QmvZRAmOIx67g27vp8U dkXLOPpf9OkLw2ZTqn7JxwF3ktoTg4BcmFrl+HB5IasXlTK+GbxCc4aNY1oM3Cd2C2u3 IhDCLLQGMij02rtGUhH8uQOJIYa0gJ8cRtQSPgeHOIU7J3cNpBYvbzi9AVuqHFR6gpRI ab6mJlHu1WZwBiJk/UAduBwW8UjiuIckfS1QbPhdCsrbrKIvk23SboncRwXDNfRFlbdA u1Og== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=uHM1D8yaoPgVu7OkaALEGbJy4kg1o1eRhm5NyrRUylM=; b=BUFVsSNhb/nFiiBdWESjBtznZPWXDppB3DI+GFfxk3fp1b41vaqc3MI/pkSMdd9Ng9 J1AnDi+K9stlRd/v0y+sFPXFnZ67o9mBwCmtpFx4R3/JBZ+2EfG6dcuISeICQWbA7yde 7vH6XOhug9OIrxqvEjNBvYhHfm6cpdmp5wBKy2HpaUZ3rkYDM7i7jBU4mJx+WJGrgTqF 020DT5IBVhk0QmQhbKVPkSB4ATTuLcA2MqaY3qr07s+gc6o888BMbHKq0XtZzUvuWMxC RYbpQoYag4gh2hM5tZKX3/RoSNeCqxNc+aNKqJxE+qVJd1/F9sWE+dg5lYpF1oBe3nlb aDZA== X-Gm-Message-State: AOAM5306xZCVAKweGa5ev0dzKkQkuHLPjvUvacDtOIjWSvPXTmNtYAvz 3RsQT6wTmxlTrg9yRKgh/phJFroksGPicZCWBU0L9g== X-Google-Smtp-Source: ABdhPJwOFY2AVkq+DSviecXMqxbtuAa8qCx0Gyx56bAvbqU5sjiGaic0Dbg30kwuz9+gBlPKxjdMeoxiUgKTvZh1Evg= X-Received: by 2002:a92:c00c:: with SMTP id q12mr2436199ild.294.1601966516666; Mon, 05 Oct 2020 23:41:56 -0700 (PDT) MIME-Version: 1.0 References: <20200930014058.44460-1-luka.kovacic@sartura.hr> <20200930014058.44460-5-luka.kovacic@sartura.hr> <20200930194759.GA24378@amd> In-Reply-To: <20200930194759.GA24378@amd> From: Luka Kovacic Date: Tue, 6 Oct 2020 08:41:45 +0200 Message-ID: Subject: Re: [PATCH v3 4/7] drivers: leds: Add the iEi WT61P803 PUZZLE LED driver To: Pavel Machek X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201006_024200_445465_F6828367 X-CRM114-Status: GOOD ( 19.69 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-hwmon@vger.kernel.org, Andrew Lunn , Jean Delvare , Luka Perkov , Jason Cooper , Gregory Clement , Guenter Roeck , Linux Kernel Mailing List , Marek Behun , Rob Herring , linux-arm Mailing List , Robert Marko , Lee Jones , Linux LED Subsystem , Dan Murphy Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Sep 30, 2020 at 9:48 PM Pavel Machek wrote: > > Hi! > > > +static int iei_wt61p803_puzzle_led_brightness_set_blocking(struct led_classdev *cdev, > > + enum led_brightness brightness) > > +{ > > + struct iei_wt61p803_puzzle_led *priv = cdev_to_iei_wt61p803_puzzle_led(cdev); > > + unsigned char *resp_buf = priv->response_buffer; > > + unsigned char led_power_cmd[5] = { > > + IEI_WT61P803_PUZZLE_CMD_HEADER_START, > > + IEI_WT61P803_PUZZLE_CMD_LED, > > + IEI_WT61P803_PUZZLE_CMD_LED_POWER, > > + (char)IEI_LED_OFF > > + }; > > + size_t reply_size; > > + > > + mutex_lock(&priv->lock); > > + if (brightness == LED_OFF) { > > + led_power_cmd[3] = (char)IEI_LED_OFF; > > + priv->led_power_state = LED_OFF; > > + } else { > > + led_power_cmd[3] = (char)IEI_LED_ON; > > + priv->led_power_state = LED_ON; > > + } > > + mutex_unlock(&priv->lock); > > + > > + return iei_wt61p803_puzzle_write_command(priv->mcu, led_power_cmd, > > + sizeof(led_power_cmd), resp_buf, &reply_size); > > +} > > Is the mutex needed? If so, should it include the > iei_wt61p803_puzzle_write_command()? Does > iei_wt61p803_puzzle_write_command() have internal locking to prevent > two messages from being mingled? > > Best regards, > Pavel > > -- > (english) http://www.livejournal.com/~pavelmachek > (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html Hello Pavel, The mutex isn't needed and can be removed. The function iei_wt61p803_puzzle_write_command() already handles its own mutex locking, so a separate mutex isn't required. Does brightness_set_blocking only block a single caller (each caller separately) or does it block all callers until the previous caller is finished? Kind regards, Luka _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel