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=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED 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 672F8C07E85 for ; Tue, 11 Dec 2018 11:18:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2E87D20849 for ; Tue, 11 Dec 2018 11:18:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2E87D20849 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=collabora.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726281AbeLKLSP (ORCPT ); Tue, 11 Dec 2018 06:18:15 -0500 Received: from bhuna.collabora.co.uk ([46.235.227.227]:46954 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726170AbeLKLSP (ORCPT ); Tue, 11 Dec 2018 06:18:15 -0500 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: eballetbo) with ESMTPSA id 02A52263BCE Subject: Re: [PATCH v3 7/8] platform/chrome: cros_ec_lightbar: instantiate only if the EC has a lightbar. To: Guenter Roeck Cc: Lee Jones , Gwendal Grignou , Nicolas Boichat , linux-kernel , Guenter Roeck , kernel@collabora.com, Benson Leung , Olof Johansson References: <20181127121849.23975-1-enric.balletbo@collabora.com> <20181127121849.23975-8-enric.balletbo@collabora.com> From: Enric Balletbo i Serra Message-ID: Date: Tue, 11 Dec 2018 12:18:10 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.3.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/12/18 19:20, Guenter Roeck wrote: > On Tue, Nov 27, 2018 at 4:19 AM Enric Balletbo i Serra > wrote: >> >> Due to the way attribute groups visibility work, the function >> cros_ec_lightbar_attrs_are_visible is called multiple times, once per >> attribute, and each of these calls makes an EC transaction. For what is >> worth the EC log reports multiple errors on boot when the lightbar is >> not available. Instead, check if the EC has a lightbar in the probe >> function and only instantiate the device. >> >> Ideally we should have instantiate the driver only if the >> EC_FEATURE_LIGHTBAR is defined, but that's not possible because that flag >> is not in the very first Pixel Chromebook (Link), only on Samus. So, the >> driver is instantiated by his parent always. >> >> This patch changes a bit the actual behaviour. Before the patch if an EC >> doesn't have a lightbar an empty lightbar folder is created in >> /sys/class/chromeos/, after the patch the empty folder is not >> created, so, the folder is only created if the lightbar exists. >> >> Signed-off-by: Enric Balletbo i Serra > > Nitpicks, otherwise > > Reviewed-by: Guenter Roeck > >> --- >> >> Changes in v3: None >> Changes in v2: >> - Removed ec_with_lightbar variable. >> >> drivers/platform/chrome/cros_ec_lightbar.c | 37 ++++++++-------------- >> 1 file changed, 13 insertions(+), 24 deletions(-) >> >> diff --git a/drivers/platform/chrome/cros_ec_lightbar.c b/drivers/platform/chrome/cros_ec_lightbar.c >> index 80eed6317570..6f6a4cbfc3fc 100644 >> --- a/drivers/platform/chrome/cros_ec_lightbar.c >> +++ b/drivers/platform/chrome/cros_ec_lightbar.c >> @@ -43,7 +43,6 @@ static unsigned long lb_interval_jiffies = 50 * HZ / 1000; >> * If this is true, we won't do anything during suspend/resume. >> */ >> static bool userspace_control; >> -static struct cros_ec_dev *ec_with_lightbar; >> >> static ssize_t interval_msec_show(struct device *dev, >> struct device_attribute *attr, char *buf) >> @@ -381,9 +380,6 @@ static int lb_manual_suspend_ctrl(struct cros_ec_dev *ec, uint8_t enable) >> struct cros_ec_command *msg; >> int ret; >> >> - if (ec != ec_with_lightbar) >> - return 0; >> - >> msg = alloc_lightbar_cmd_msg(ec); >> if (!msg) >> return -ENOMEM; >> @@ -567,37 +563,26 @@ static struct attribute *__lb_cmds_attrs[] = { >> NULL, >> }; >> >> -static bool ec_has_lightbar(struct cros_ec_dev *ec) >> +static bool cros_ec_has_lightbar(struct cros_ec_dev *ec_dev) >> { >> - return !!get_lightbar_version(ec, NULL, NULL); >> -} >> - >> -static umode_t cros_ec_lightbar_attrs_are_visible(struct kobject *kobj, >> - struct attribute *a, int n) >> -{ >> - struct device *dev = container_of(kobj, struct device, kobj); >> - struct cros_ec_dev *ec = to_cros_ec_dev(dev); >> - struct platform_device *pdev = to_platform_device(ec->dev); >> + struct platform_device *pdev = to_platform_device(ec_dev->dev); >> struct cros_ec_platform *pdata = pdev->dev.platform_data; >> int is_cros_ec; >> >> is_cros_ec = strcmp(pdata->ec_name, CROS_EC_DEV_NAME); >> >> if (is_cros_ec != 0) >> - return 0; >> + return false; >> > FWIW, is_cros_ec is really unnecessary here, though I guess that might > be a different patch. > >> - /* Only instantiate this stuff if the EC has a lightbar */ >> - if (ec_has_lightbar(ec)) { >> - ec_with_lightbar = ec; >> - return a->mode; >> - } >> - return 0; >> + if (!!get_lightbar_version(ec_dev, NULL, NULL)) >> + return true; >> + >> + return false; > > Why not just the following ? > return !!get_lightbar_version(ec_dev, NULL, NULL); > or even > return !strcmp(pdata->ec_name, CROS_EC_DEV_NAME) && > !!get_lightbar_version(ec_dev, NULL, NULL); > Ack, I think that we can get rid of the cros_ec_has_lightbar function then. I'll do in next version. Thanks, Enric >> } >> >> struct attribute_group cros_ec_lightbar_attr_group = { >> .name = "lightbar", >> .attrs = __lb_cmds_attrs, >> - .is_visible = cros_ec_lightbar_attrs_are_visible, >> }; >> >> static int cros_ec_lightbar_probe(struct platform_device *pd) >> @@ -606,6 +591,10 @@ static int cros_ec_lightbar_probe(struct platform_device *pd) >> struct device *dev = &pd->dev; >> int ret; >> >> + /* Only instantiate this stuff if the EC has a lightbar */ >> + if (!cros_ec_has_lightbar(ec_dev)) >> + return -ENODEV; >> + >> /* Take control of the lightbar from the EC. */ >> lb_manual_suspend_ctrl(ec_dev, 1); >> >> @@ -635,7 +624,7 @@ static int __maybe_unused cros_ec_lightbar_resume(struct device *dev) >> { >> struct cros_ec_dev *ec_dev = dev_get_drvdata(dev); >> >> - if (userspace_control || ec_dev != ec_with_lightbar) >> + if (userspace_control) >> return 0; >> >> return lb_send_empty_cmd(ec_dev, LIGHTBAR_CMD_RESUME); >> @@ -645,7 +634,7 @@ static int __maybe_unused cros_ec_lightbar_suspend(struct device *dev) >> { >> struct cros_ec_dev *ec_dev = dev_get_drvdata(dev); >> >> - if (userspace_control || ec_dev != ec_with_lightbar) >> + if (userspace_control) >> return 0; >> >> return lb_send_empty_cmd(ec_dev, LIGHTBAR_CMD_SUSPEND); >> -- >> 2.19.1 >>