From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756088AbaIOUAQ (ORCPT ); Mon, 15 Sep 2014 16:00:16 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:43399 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755157AbaIOUAM (ORCPT ); Mon, 15 Sep 2014 16:00:12 -0400 Date: Mon, 15 Sep 2014 13:00:07 -0700 From: Darren Hart To: Frans Klaver Cc: Corentin Chary , Rafael Wysocki , Greg Kroah-Hartman , acpi4asus-user@lists.sourceforge.net, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 07/13] eeepc-laptop: make disp attribute really write-only Message-ID: <20140915200007.GB62440@vmdeb7> References: <1410563212-31565-1-git-send-email-fransklaver@gmail.com> <1410563212-31565-8-git-send-email-fransklaver@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1410563212-31565-8-git-send-email-fransklaver@gmail.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Sep 13, 2014 at 01:06:46AM +0200, Frans Klaver wrote: > The disp attribute is write-only, but sysfs doesn't know this. Currently > show_sys_acpi() is mimicking sysfs behavior, if the underlying acpi call > should fail. This is not ideal; behaving like sysfs is better left to > sysfs. > > Introduce EEEPC_CREATE_DEVICE_ATTR_WO() to instantiate a write-only > attribute, and declare the disp attribute with it. Sysfs makes sure > userspace can only write to disp at all times. This also means we can > back to propagating any errors from get_acpi(). > > Signed-off-by: Frans Klaver > --- > drivers/platform/x86/eeepc-laptop.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) > > diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c > index 3c04b77..4f6490d 100644 > --- a/drivers/platform/x86/eeepc-laptop.c > +++ b/drivers/platform/x86/eeepc-laptop.c > @@ -291,7 +291,7 @@ static ssize_t show_sys_acpi(struct device *dev, int cm, char *buf) > int value = get_acpi(eeepc, cm); > > if (value < 0) > - return -EIO; > + return value; > return sprintf(buf, "%d\n", value); > } > > @@ -316,9 +316,13 @@ static ssize_t show_sys_acpi(struct device *dev, int cm, char *buf) > EEEPC_ACPI_STORE_FUNC(_name, _cm) \ > static DEVICE_ATTR(_name, _mode, show_##_name, store_##_name) > > +#define EEEPC_CREATE_DEVICE_ATTR_WO(_name, _mode, _cm) \ > + EEEPC_ACPI_STORE_FUNC(_name, _cm) \ > + static DEVICE_ATTR(_name, _mode, NULL, store_##_name) Per Greg's previous reply, I presume DEVICE_ATTR_WO here? > + > EEEPC_CREATE_DEVICE_ATTR(camera, S_IWUSR | S_IRUGO, CM_ASL_CAMERA); > EEEPC_CREATE_DEVICE_ATTR(cardr, S_IWUSR | S_IRUGO, CM_ASL_CARDREADER); > -EEEPC_CREATE_DEVICE_ATTR(disp, S_IWUSR, CM_ASL_DISPLAYSWITCH); > +EEEPC_CREATE_DEVICE_ATTR_WO(disp, S_IWUSR, CM_ASL_DISPLAYSWITCH); > > struct eeepc_cpufv { > int num; > -- > 2.1.0 > > -- > To unsubscribe from this list: send the line "unsubscribe platform-driver-x86" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Darren Hart Intel Open Source Technology Center