From patchwork Tue Sep 4 14:24:38 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Lu X-Patchwork-Id: 181588 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id B34EC2C009A for ; Wed, 5 Sep 2012 00:25:57 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932288Ab2IDOZx (ORCPT ); Tue, 4 Sep 2012 10:25:53 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:44458 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932244Ab2IDOZu (ORCPT ); Tue, 4 Sep 2012 10:25:50 -0400 Received: by mail-pb0-f46.google.com with SMTP id rr13so9559178pbb.19 for ; Tue, 04 Sep 2012 07:25:49 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; bh=x40Z3sq2VaSHkHQ+g+H4IxszgmYZs4M9eO3oHfWBkNM=; b=J3m2PR3hm1CE9C6b3txunOmGOBwZSqu03uz3aoA69qB3RHNqNhXC8ovPuLSJqaVLLq KrBQD0gTPgKpk4THHYiK8/2VuWna8cwhHxv030CrP3LkD3PSSea4xfCuxamWCL6MIsID d5gKQfZyAs48JfNBofJz+1Q1Ut285eWCqyN7Ilv/tljAeDU65+a1IwCpVwML3zPLP1TO mX/AV+YTDPht6oPwrWWkRnRWLoIF7fTLio9WAocCEX0QFcNERRkTW2FiMeyJtTYRRxvw yBUIiV9OiiUNUZoOjTJlxyWFA8LBA2q3DHCrOSqZNZ+rj70q4FRGFwq7+JBJCWUxAReH XDbw== Received: by 10.66.87.132 with SMTP id ay4mr41384525pab.82.1346768749710; Tue, 04 Sep 2012 07:25:49 -0700 (PDT) Received: from localhost.localdomain.localdomain ([180.157.93.243]) by mx.google.com with ESMTPS id lb1sm12311440pbc.47.2012.09.04.07.25.43 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 04 Sep 2012 07:25:49 -0700 (PDT) From: Aaron Lu To: Alan Stern , James Bottomley , Jeff Garzik Cc: linux-scsi@vger.kernel.org, linux-ide@vger.kernel.org, linux-pm@vger.kernel.org, linux-acpi@vger.kernel.org, Aaron Lu , Aaron Lu Subject: [PATCH v6 5/7] scsi: pm: add may_power_off flag Date: Tue, 4 Sep 2012 22:24:38 +0800 Message-Id: <1346768680-7287-6-git-send-email-aaron.lwe@gmail.com> X-Mailer: git-send-email 1.7.11.3 In-Reply-To: <1346768680-7287-1-git-send-email-aaron.lwe@gmail.com> References: <1346768680-7287-1-git-send-email-aaron.lwe@gmail.com> Sender: linux-ide-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ide@vger.kernel.org From: Aaron Lu Add a new flag may_power_off for scsi device, it gives the user a chance to control when the device is runtime suspended, can we remove its power if possible. And if the device can be powered off(reflected by can_power_off flag, determined by individual driver), create a sysfs entry named may_power_off to let user control the flag. When user changes this flag through sysfs entry and if the device is already runtime suspended, runtime resume it so that it can respect this flag next time it is runtime suspended. I'm planning using this flag for sr and sd. Signed-off-by: Aaron Lu --- drivers/scsi/scsi_sysfs.c | 37 ++++++++++++++++++++++++++++++++++++- include/scsi/scsi_device.h | 1 + 2 files changed, 37 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 093d4f6..8c8efd3 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -509,6 +509,7 @@ sdev_store_##field (struct device *dev, struct device_attribute *attr, \ return ret; \ } \ static DEVICE_ATTR(field, S_IRUGO | S_IWUSR, sdev_show_##field, sdev_store_##field); +#endif /* * scsi_sdev_check_buf_bit: return 0 if buf is "0", return 1 if buf is "1", @@ -526,7 +527,7 @@ static int scsi_sdev_check_buf_bit(const char *buf) } else return -EINVAL; } -#endif + /* * Create the actual show/store functions and data structures. */ @@ -860,6 +861,37 @@ static struct device_attribute sdev_attr_queue_type_rw = __ATTR(queue_type, S_IRUGO | S_IWUSR, show_queue_type_field, sdev_store_queue_type_rw); +static ssize_t +sdev_show_may_power_off(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct scsi_device *sdev; + sdev = to_scsi_device(dev); + return snprintf (buf, 20, "%d\n", sdev->may_power_off); +} + +static ssize_t +sdev_store_may_power_off(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + int ret; + struct scsi_device *sdev; + + ret = scsi_sdev_check_buf_bit(buf); + if (ret >= 0) { + sdev = to_scsi_device(dev); + if (sdev->may_power_off != ret) { + sdev->may_power_off = ret; + if (pm_runtime_suspended(dev)) + pm_runtime_resume(dev); + } + ret = count; + } + return ret; +} +static DEVICE_ATTR(may_power_off, S_IRUGO | S_IWUSR, + sdev_show_may_power_off, sdev_store_may_power_off); + /** * scsi_sysfs_add_sdev - add scsi device to sysfs * @sdev: scsi_device to add @@ -950,6 +982,9 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev) } } + if (sdev->can_power_off) + device_create_file(&sdev->sdev_gendev, &dev_attr_may_power_off); + return error; } diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index 72d946f..41cec7f 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -157,6 +157,7 @@ struct scsi_device { unsigned can_power_off:1; /* Device supports runtime power off */ unsigned wce_default_on:1; /* Cache is ON by default */ unsigned wakeup_by_user:1; /* User wakes up the device */ + unsigned may_power_off:1; /* Power off is allowed by user */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ struct list_head event_list; /* asserted events */