Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753249Ab3C1KGe (ORCPT ); Thu, 28 Mar 2013 06:06:34 -0400 Received: from mail-qc0-f174.google.com ([209.85.216.174]:61588 "EHLO mail-qc0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752489Ab3C1KGc (ORCPT ); Thu, 28 Mar 2013 06:06:32 -0400 MIME-Version: 1.0 In-Reply-To: <1650338.UonQ4LqB70@avalon> References: <1364460632-21697-1-git-send-email-prabhakar.csengg@gmail.com> <1650338.UonQ4LqB70@avalon> From: Prabhakar Lad Date: Thu, 28 Mar 2013 15:36:11 +0530 Message-ID: Subject: Re: [PATCH] davinci: vpif: add pm_runtime support To: Laurent Pinchart Cc: DLOS , LMML , LKML , Mauro Carvalho Chehab , Hans Verkuil , Sakari Ailus Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3652 Lines: 122 Hi Laurent, Thanks for the quick review! On Thu, Mar 28, 2013 at 2:39 PM, Laurent Pinchart wrote: > Hi Prabhakar, > > Thanks for the patch. > > On Thursday 28 March 2013 14:20:32 Prabhakar lad wrote: >> From: Lad, Prabhakar >> >> Add pm_runtime support to the TI Davinci VPIF driver. >> Along side this patch replaces clk_get() with devm_clk_get() >> to simplify the error handling. >> >> Signed-off-by: Lad, Prabhakar >> --- >> drivers/media/platform/davinci/vpif.c | 21 +++++++++++---------- >> 1 files changed, 11 insertions(+), 10 deletions(-) >> >> diff --git a/drivers/media/platform/davinci/vpif.c >> b/drivers/media/platform/davinci/vpif.c index 28638a8..7d14625 100644 >> --- a/drivers/media/platform/davinci/vpif.c >> +++ b/drivers/media/platform/davinci/vpif.c >> @@ -25,6 +25,7 @@ >> #include >> #include >> #include >> +#include >> #include >> >> #include >> @@ -44,7 +45,6 @@ static struct resource *res; >> spinlock_t vpif_lock; >> >> void __iomem *vpif_base; >> -struct clk *vpif_clk; >> >> /** >> * ch_params: video standard configuration parameters for vpif >> @@ -421,6 +421,7 @@ EXPORT_SYMBOL(vpif_channel_getfid); >> >> static int vpif_probe(struct platform_device *pdev) >> { >> + struct clk *vpif_clk; >> int status = 0; >> >> res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> @@ -439,12 +440,17 @@ static int vpif_probe(struct platform_device *pdev) >> goto fail; >> } >> >> - vpif_clk = clk_get(&pdev->dev, "vpif"); >> + vpif_clk = devm_clk_get(&pdev->dev, "vpif"); >> if (IS_ERR(vpif_clk)) { >> status = PTR_ERR(vpif_clk); >> goto clk_fail; >> } >> - clk_prepare_enable(vpif_clk); >> + clk_put(vpif_clk); > > Why do you need to call clk_put() here ? > The above check is to see if the clock is provided, once done we free it using clk_put(). >> + pm_runtime_enable(&pdev->dev); >> + pm_runtime_resume(&pdev->dev); >> + >> + pm_runtime_get(&pdev->dev); > > Does runtime PM automatically handle your clock ? If so can't you remove clock > handling from the driver completely ? > Yes pm runtime take care of enabling/disabling the clocks so that we don't have to do it in drivers. I believe clock handling is removed with this patch, with just devm_clk_get() remaining ;) Regards, --Prabhakar >> spin_lock_init(&vpif_lock); >> dev_info(&pdev->dev, "vpif probe success\n"); >> @@ -459,11 +465,6 @@ fail: >> >> static int vpif_remove(struct platform_device *pdev) >> { >> - if (vpif_clk) { >> - clk_disable_unprepare(vpif_clk); >> - clk_put(vpif_clk); >> - } >> - >> iounmap(vpif_base); >> release_mem_region(res->start, res_len); >> return 0; >> @@ -472,13 +473,13 @@ static int vpif_remove(struct platform_device *pdev) >> #ifdef CONFIG_PM >> static int vpif_suspend(struct device *dev) >> { >> - clk_disable_unprepare(vpif_clk); >> + pm_runtime_put(dev); >> return 0; >> } >> >> static int vpif_resume(struct device *dev) >> { >> - clk_prepare_enable(vpif_clk); >> + pm_runtime_get(dev); >> return 0; >> } > -- > Regards, > > Laurent Pinchart > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/