From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e33.co.us.ibm.com (e33.co.us.ibm.com [32.97.110.151]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id A1FCA2C032C for ; Sat, 1 Feb 2014 10:58:24 +1100 (EST) Received: from /spool/local by e33.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 31 Jan 2014 16:58:22 -0700 Received: from b03cxnp08028.gho.boulder.ibm.com (b03cxnp08028.gho.boulder.ibm.com [9.17.130.20]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 8930C1FF001A for ; Fri, 31 Jan 2014 16:58:20 -0700 (MST) Received: from d03av05.boulder.ibm.com (d03av05.boulder.ibm.com [9.17.195.85]) by b03cxnp08028.gho.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s0VNwKgC5243388 for ; Sat, 1 Feb 2014 00:58:20 +0100 Received: from d03av05.boulder.ibm.com (localhost [127.0.0.1]) by d03av05.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s0VNwJAP013265 for ; Fri, 31 Jan 2014 16:58:20 -0700 From: Tyrel Datwyler To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v3 3/3] powerpc/pseries: Report in kernel device tree update to drmgr Date: Fri, 31 Jan 2014 15:58:12 -0800 Message-Id: <1391212692-16217-4-git-send-email-tyreld@linux.vnet.ibm.com> In-Reply-To: <1391212692-16217-1-git-send-email-tyreld@linux.vnet.ibm.com> References: <1391212692-16217-1-git-send-email-tyreld@linux.vnet.ibm.com> Cc: nfont@linux.vnet.ibm.com, Tyrel Datwyler List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Traditionally it has been drmgr's responsibilty to update the device tree through the /proc/ppc64/ofdt interface after a suspend/resume operation. This patchset however has modified suspend/resume ops to preform that update entirely in the kernel during the resume. Therefore, a mechanism is required for drmgr to determine who is responsible for the update. This patch adds a show function to the "hibernate" attribute that returns 1 if the kernel updates the device tree after the resume and 0 if drmgr is responsible. Signed-off-by: Tyrel Datwyler --- arch/powerpc/platforms/pseries/suspend.c | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/platforms/pseries/suspend.c b/arch/powerpc/platforms/pseries/suspend.c index 1d9c580..b87b978 100644 --- a/arch/powerpc/platforms/pseries/suspend.c +++ b/arch/powerpc/platforms/pseries/suspend.c @@ -192,7 +192,30 @@ out: return rc; } -static DEVICE_ATTR(hibernate, S_IWUSR, NULL, store_hibernate); +#define USER_DT_UPDATE 0 +#define KERN_DT_UPDATE 1 + +/** + * show_hibernate - Report device tree update responsibilty + * @dev: subsys root device + * @attr: device attribute struct + * @buf: buffer + * + * Report whether a device tree update is performed by the kernel after a + * resume, or if drmgr must coordinate the update from user space. + * + * Return value: + * 0 if drmgr is to initiate update, and 1 otherwise + **/ +static ssize_t show_hibernate(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", KERN_DT_UPDATE); +} + +static DEVICE_ATTR(hibernate, S_IWUSR | S_IRUGO, + show_hibernate, store_hibernate); static struct bus_type suspend_subsys = { .name = "power", -- 1.7.12.2