From patchwork Fri Aug 14 10:49:38 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Magnus Damm X-Patchwork-Id: 41373 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n7EArFaX025527 for ; Fri, 14 Aug 2009 10:54:03 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754517AbZHNKyB (ORCPT ); Fri, 14 Aug 2009 06:54:01 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754678AbZHNKyB (ORCPT ); Fri, 14 Aug 2009 06:54:01 -0400 Received: from rv-out-0506.google.com ([209.85.198.231]:8647 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754517AbZHNKyA (ORCPT ); Fri, 14 Aug 2009 06:54:00 -0400 Received: by rv-out-0506.google.com with SMTP id f6so428299rvb.1 for ; Fri, 14 Aug 2009 03:54:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:from:to:cc:date:message-id :in-reply-to:references:subject; bh=j+aZ/bhQ1aB8Vivc1MEPZmjxsCHRuh29xJCy90iAYcw=; b=CZqpLd1GeoUKq+1nbuvrRNwYwbV/MshlhnqD7EaYIeqXfFWKjQ27zUo9STco0G/6Qw /pCKqrmu3IT3x83jWER5NYLQ3b4CDYCAC4obCRTfESGuj6lyFIhnaOM/YJOGnkikDoNv YcwbafD4rB68rZ1ufUuzQMQm4tu1p4joCxhzw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=from:to:cc:date:message-id:in-reply-to:references:subject; b=vjwFflMr60htt0h/Io/V1ClqfQfAWGYnTblbniU40MYGw3g3QalgTr//WDyU0cU09X Flfrmak2d46J0mnvQ5BUfNA+XhIbF++TVRfbAqNt5MEZpLsV1XPlCEPvne2DicXfACCG Nzg6GWK5VyCiy+PDJCHzWyMGCdQzDPyqmUx4A= Received: by 10.140.144.14 with SMTP id r14mr956156rvd.60.1250247241911; Fri, 14 Aug 2009 03:54:01 -0700 (PDT) Received: from rx1.opensource.se (mailhost.igel.co.jp [219.106.231.130]) by mx.google.com with ESMTPS id c20sm6760276rvf.41.2009.08.14.03.53.59 (version=TLSv1/SSLv3 cipher=RC4-MD5); Fri, 14 Aug 2009 03:54:01 -0700 (PDT) From: Magnus Damm To: linux-pm@lists.linux-foundation.org Cc: linux-sh@vger.kernel.org, gregkh@suse.de, rjw@sisk.pl, lethal@linux-sh.org, stern@rowland.harvard.edu, pavel@ucw.cz, Magnus Damm Date: Fri, 14 Aug 2009 19:49:38 +0900 Message-Id: <20090814104938.32396.56126.sendpatchset@rx1.opensource.se> In-Reply-To: <20090814104808.32396.50021.sendpatchset@rx1.opensource.se> References: <20090814104808.32396.50021.sendpatchset@rx1.opensource.se> Subject: [PATCH 05/05] uio: Runtime PM for UIO devices Sender: linux-sh-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sh@vger.kernel.org From: Magnus Damm This patch modifies the uio_pdrv_genirq driver to support Runtime PM. The power management implementation simply runtime resumes the device at open() time and runtime suspends it at release() time. The user space driver is responsible for re-initializing the hardware after open(). Signed-off-by: Magnus Damm --- Tested with the sh7722 VEU hardware block using the mplayer sh_veu vidix user space driver. Changes since V2: - updated comments drivers/uio/uio_pdrv_genirq.c | 54 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html --- 0001/drivers/uio/uio_pdrv_genirq.c +++ work/drivers/uio/uio_pdrv_genirq.c 2009-08-14 18:13:32.000000000 +0900 @@ -20,6 +20,7 @@ #include #include #include +#include #define DRIVER_NAME "uio_pdrv_genirq" @@ -27,8 +28,27 @@ struct uio_pdrv_genirq_platdata { struct uio_info *uioinfo; spinlock_t lock; unsigned long flags; + struct platform_device *pdev; }; +static int uio_pdrv_genirq_open(struct uio_info *info, struct inode *inode) +{ + struct uio_pdrv_genirq_platdata *priv = info->priv; + + /* Wait until the Runtime PM code has woken up the device */ + pm_runtime_get_sync(&priv->pdev->dev); + return 0; +} + +static int uio_pdrv_genirq_release(struct uio_info *info, struct inode *inode) +{ + struct uio_pdrv_genirq_platdata *priv = info->priv; + + /* Tell the Runtime PM code that the device has become idle */ + pm_runtime_put_sync(&priv->pdev->dev); + return 0; +} + static irqreturn_t uio_pdrv_genirq_handler(int irq, struct uio_info *dev_info) { struct uio_pdrv_genirq_platdata *priv = dev_info->priv; @@ -97,6 +117,7 @@ static int uio_pdrv_genirq_probe(struct priv->uioinfo = uioinfo; spin_lock_init(&priv->lock); priv->flags = 0; /* interrupt is enabled to begin with */ + priv->pdev = pdev; uiomem = &uioinfo->mem[0]; @@ -136,8 +157,17 @@ static int uio_pdrv_genirq_probe(struct uioinfo->irq_flags |= IRQF_DISABLED; uioinfo->handler = uio_pdrv_genirq_handler; uioinfo->irqcontrol = uio_pdrv_genirq_irqcontrol; + uioinfo->open = uio_pdrv_genirq_open; + uioinfo->release = uio_pdrv_genirq_release; uioinfo->priv = priv; + /* Enable Runtime PM for this device: + * The device starts in suspended state to allow the hardware to be + * turned off by default. The Runtime PM bus code should power on the + * hardware and enable clocks at open(). + */ + pm_runtime_enable(&pdev->dev); + ret = uio_register_device(&pdev->dev, priv->uioinfo); if (ret) { dev_err(&pdev->dev, "unable to register uio device\n"); @@ -157,16 +187,40 @@ static int uio_pdrv_genirq_remove(struct struct uio_pdrv_genirq_platdata *priv = platform_get_drvdata(pdev); uio_unregister_device(priv->uioinfo); + pm_runtime_disable(&pdev->dev); kfree(priv); return 0; } +static int uio_pdrv_genirq_runtime_nop(struct device *dev) +{ + /* Runtime PM callback shared between ->runtime_suspend() + * and ->runtime_resume(). Simply returns success. + * + * In this driver pm_runtime_get_sync() and pm_runtime_put_sync() + * are used at open() and release() time. This allows the + * Runtime PM code to turn off power to the device while the + * device is unused, ie before open() and after release(). + * + * This Runtime PM callback does not need to save or restore + * any registers since user space is responsbile for hardware + * register reinitialization after open(). + */ + return 0; +} + +static struct dev_pm_ops uio_pdrv_genirq_dev_pm_ops = { + .runtime_suspend = uio_pdrv_genirq_runtime_nop, + .runtime_resume = uio_pdrv_genirq_runtime_nop, +}; + static struct platform_driver uio_pdrv_genirq = { .probe = uio_pdrv_genirq_probe, .remove = uio_pdrv_genirq_remove, .driver = { .name = DRIVER_NAME, .owner = THIS_MODULE, + .pm = &uio_pdrv_genirq_dev_pm_ops, }, };