From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e31.co.us.ibm.com (e31.co.us.ibm.com [32.97.110.149]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 99E9A2C0257 for ; Thu, 23 Jan 2014 07:06:20 +1100 (EST) Received: from /spool/local by e31.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 22 Jan 2014 13:06:17 -0700 Received: from b03cxnp08026.gho.boulder.ibm.com (b03cxnp08026.gho.boulder.ibm.com [9.17.130.18]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 64E5219D804E for ; Wed, 22 Jan 2014 13:06:04 -0700 (MST) Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by b03cxnp08026.gho.boulder.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id s0MK5xDj66781330 for ; Wed, 22 Jan 2014 21:06:00 +0100 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id s0MK6DA5013824 for ; Wed, 22 Jan 2014 13:06:13 -0700 From: Tyrel Datwyler To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v2 3/3] powerpc/pseries: Report in kernel device tree update to drmgr Date: Wed, 22 Jan 2014 14:58:37 -0500 Message-Id: <1390420717-23907-4-git-send-email-tyreld@linux.vnet.ibm.com> In-Reply-To: <1390420717-23907-1-git-send-email-tyreld@linux.vnet.ibm.com> References: <1390420717-23907-1-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 16a2552..723115d 100644 --- a/arch/powerpc/platforms/pseries/suspend.c +++ b/arch/powerpc/platforms/pseries/suspend.c @@ -174,7 +174,30 @@ 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", -- 1.7.12.4