From patchwork Fri Jul 31 14:02:52 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Magnus Damm X-Patchwork-Id: 38516 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 n6VE79Xh008229 for ; Fri, 31 Jul 2009 14:07:09 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751896AbZGaOHH (ORCPT ); Fri, 31 Jul 2009 10:07:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751903AbZGaOHH (ORCPT ); Fri, 31 Jul 2009 10:07:07 -0400 Received: from mail-ew0-f214.google.com ([209.85.219.214]:43485 "EHLO mail-ew0-f214.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751896AbZGaOHF (ORCPT ); Fri, 31 Jul 2009 10:07:05 -0400 Received: by mail-ew0-f214.google.com with SMTP id 10so1526314ewy.37 for ; Fri, 31 Jul 2009 07:07:06 -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=1pVLuItN1AgaUEBh3taGZS0vv1qPy3X2qz+ciRlYZ1E=; b=QHHnFJycsMHTWp3KPdN9IFqI3mqKsYCyx2loTMvQIKMjSrw4pmgYN07op/kZLuXyv0 kE368QMwMbzKDGwChHviITj5A3CWkvIRS8yIJUUs1p3BXVVZPnEGKhcJb28a3YSqXxNn EY8S6/y38dzZ9tS8lpXMSh6k2J5y2mZU9himw= 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=LPp7OdXbJdsYZ7a1cTA18z/lJvv5v971wuVC6uCVYRobQUcQozGAJ5pO7+11J++eG5 fHRHnc3jQH30v1Nx+Kspg0VGvhkl6u2fwcfe1TpwyTYcYNJshZc4mDTaW8QX8NXMH9KC n1n5T9hUVh2taZ8zb18M/cz+TCdguhA53OfXs= Received: by 10.210.52.15 with SMTP id z15mr957689ebz.36.1249049226059; Fri, 31 Jul 2009 07:07:06 -0700 (PDT) Received: from rx1.opensource.se (210-225-125-011.jp.fiberphone.net [210.225.125.11]) by mx.google.com with ESMTPS id 7sm3439918eyb.47.2009.07.31.07.07.00 (version=TLSv1/SSLv3 cipher=RC4-MD5); Fri, 31 Jul 2009 07:07:05 -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, 31 Jul 2009 23:02:52 +0900 Message-Id: <20090731140252.11351.1697.sendpatchset@rx1.opensource.se> In-Reply-To: <20090731140158.11351.26021.sendpatchset@rx1.opensource.se> References: <20090731140158.11351.26021.sendpatchset@rx1.opensource.se> Subject: [PATCH 04/04] video: Runtime PM hack for SuperH LCDC driver 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 SuperH Mobile LCDC framebuffer driver to support Runtime PM. This patch is experimental and is at this point still missing context save and restore support. With debug messages it is however already possible to see that the deferred io clock management strategy pays off since in that mode the clocks are only turned on for a short period of time to redraw the screen. When the screen is unchanged the clocks are disabled and the driver can be in runtime suspended state. Regarding pm_runtime_put_noidle()/pm_runtime_get_noresume(): This driver does not work well with the Runtime PM v11 code since it performs runtime_pm_get_sync() from probe() which is not allowed. This driver needs to access hardware registers from probe() so runtime_pm_get_sync() must really succeed in this case so the bus code gets a chance to turn on the hardware device. Signed-off-by: Magnus Damm --- Changes from V1 prototype: - use pm_runtime_get_sync() and pm_runtime_put_sync() - use pm_runtime_disable() - no need for pm_runtime_set_suspended() - incomplete runtime pm functions for dev_pm_ops - work around with pm_runtime_put_noidle()/pm_runtime_get_noresume() TODO: - quite a bit drivers/video/sh_mobile_lcdcfb.c | 47 +++++++++++++++++++++++--------------- 1 file changed, 29 insertions(+), 18 deletions(-) -- 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/video/sh_mobile_lcdcfb.c +++ work/drivers/video/sh_mobile_lcdcfb.c 2009-07-30 23:12:49.000000000 +0900 @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -42,9 +43,9 @@ struct sh_mobile_lcdc_chan { struct sh_mobile_lcdc_priv { void __iomem *base; int irq; - atomic_t clk_usecnt; + atomic_t hw_usecnt; + struct device *dev; struct clk *dot_clk; - struct clk *clk; unsigned long lddckr; struct sh_mobile_lcdc_chan ch[2]; int started; @@ -185,8 +186,8 @@ struct sh_mobile_lcdc_sys_bus_ops sh_mob static void sh_mobile_lcdc_clk_on(struct sh_mobile_lcdc_priv *priv) { - if (atomic_inc_and_test(&priv->clk_usecnt)) { - clk_enable(priv->clk); + if (atomic_inc_and_test(&priv->hw_usecnt)) { + pm_runtime_get_sync(priv->dev); if (priv->dot_clk) clk_enable(priv->dot_clk); } @@ -194,10 +195,10 @@ static void sh_mobile_lcdc_clk_on(struct static void sh_mobile_lcdc_clk_off(struct sh_mobile_lcdc_priv *priv) { - if (atomic_sub_return(1, &priv->clk_usecnt) == -1) { + if (atomic_sub_return(1, &priv->hw_usecnt) == -1) { if (priv->dot_clk) clk_disable(priv->dot_clk); - clk_disable(priv->clk); + pm_runtime_put(priv->dev); } } @@ -566,7 +567,6 @@ static int sh_mobile_lcdc_setup_clocks(s int clock_source, struct sh_mobile_lcdc_priv *priv) { - char clk_name[8]; char *str; int icksel; @@ -580,23 +580,15 @@ static int sh_mobile_lcdc_setup_clocks(s priv->lddckr = icksel << 16; - atomic_set(&priv->clk_usecnt, -1); - snprintf(clk_name, sizeof(clk_name), "lcdc%d", pdev->id); - priv->clk = clk_get(&pdev->dev, clk_name); - if (IS_ERR(priv->clk)) { - dev_err(&pdev->dev, "cannot get clock \"%s\"\n", clk_name); - return PTR_ERR(priv->clk); - } - if (str) { priv->dot_clk = clk_get(&pdev->dev, str); if (IS_ERR(priv->dot_clk)) { dev_err(&pdev->dev, "cannot get dot clock %s\n", str); - clk_put(priv->clk); return PTR_ERR(priv->dot_clk); } } - + atomic_set(&priv->hw_usecnt, -1); + pm_runtime_enable(priv->dev); return 0; } @@ -714,9 +706,18 @@ static int sh_mobile_lcdc_resume(struct return sh_mobile_lcdc_start(platform_get_drvdata(pdev)); } +static int sh_mobile_lcdc_runtime_nop(struct device *dev) +{ + /* TODO: implement register save and restore */ + + return 0; +} + static struct dev_pm_ops sh_mobile_lcdc_dev_pm_ops = { .suspend = sh_mobile_lcdc_suspend, .resume = sh_mobile_lcdc_resume, + .runtime_suspend = sh_mobile_lcdc_runtime_nop, + .runtime_resume = sh_mobile_lcdc_runtime_nop, }; static int sh_mobile_lcdc_remove(struct platform_device *pdev); @@ -753,6 +754,9 @@ static int __init sh_mobile_lcdc_probe(s goto err0; } + /* workaround: allow resume from probe() */ + pm_runtime_put_noidle(&pdev->dev); + error = request_irq(i, sh_mobile_lcdc_irq, IRQF_DISABLED, dev_name(&pdev->dev), priv); if (error) { @@ -761,6 +765,7 @@ static int __init sh_mobile_lcdc_probe(s } priv->irq = i; + priv->dev = &pdev->dev; platform_set_drvdata(pdev, priv); pdata = pdev->dev.platform_data; @@ -896,8 +901,13 @@ static int __init sh_mobile_lcdc_probe(s sh_mobile_lcdc_clk_off(priv); } + /* workaround: balance pm_runtime_put_noidle() call */ + pm_runtime_get_noresume(&pdev->dev); return 0; err1: + /* workaround: balance pm_runtime_put_noidle() call */ + pm_runtime_get_noresume(&pdev->dev); + sh_mobile_lcdc_remove(pdev); err0: return error; @@ -932,7 +942,8 @@ static int sh_mobile_lcdc_remove(struct if (priv->dot_clk) clk_put(priv->dot_clk); - clk_put(priv->clk); + + pm_runtime_disable(priv->dev); if (priv->base) iounmap(priv->base);