Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757407Ab3DAIwe (ORCPT ); Mon, 1 Apr 2013 04:52:34 -0400 Received: from mail-oa0-f46.google.com ([209.85.219.46]:57764 "EHLO mail-oa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755591Ab3DAIwc (ORCPT ); Mon, 1 Apr 2013 04:52:32 -0400 MIME-Version: 1.0 In-Reply-To: References: <1364798210-31517-1-git-send-email-prabhakar.csengg@gmail.com> Date: Mon, 1 Apr 2013 14:22:32 +0530 Message-ID: Subject: Re: [PATCH v2] davinci: vpif: add pm_runtime support From: Rajagopal Venkat To: Prabhakar Lad Cc: DLOS , LMML , LKML , Mauro Carvalho Chehab , Hans Verkuil , Laurent Pinchart , Sakari Ailus , Sekhar Nori 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: 2984 Lines: 85 On 1 April 2013 13:53, Prabhakar Lad wrote: > On Mon, Apr 1, 2013 at 12:47 PM, Rajagopal Venkat > wrote: >> On 1 April 2013 12:06, Prabhakar lad wrote: >>> From: Lad, Prabhakar >>> >>> Add pm_runtime support to the TI Davinci VPIF driver. >>> >>> Signed-off-by: Lad, Prabhakar >>> Cc: Mauro Carvalho Chehab >>> Cc: Hans Verkuil >>> Cc: Laurent Pinchart >>> Cc: Sakari Ailus >>> Cc: Sekhar Nori >>> --- >>> Changes for v2: >>> 1: Removed use of clk API as pointed by Laurent and Sekhar. >>> >>> drivers/media/platform/davinci/vpif.c | 24 +++++++----------------- >>> 1 files changed, 7 insertions(+), 17 deletions(-) >>> >>> diff --git a/drivers/media/platform/davinci/vpif.c b/drivers/media/platform/davinci/vpif.c >>> index 28638a8..599cabb 100644 >>> --- a/drivers/media/platform/davinci/vpif.c >>> +++ b/drivers/media/platform/davinci/vpif.c >>> @@ -23,8 +23,8 @@ >>> #include >>> #include >>> #include >>> -#include >>> #include >>> +#include >>> #include >>> >>> #include >>> @@ -44,7 +44,6 @@ static struct resource *res; >>> spinlock_t vpif_lock; >>> >>> void __iomem *vpif_base; >>> -struct clk *vpif_clk; >>> >>> /** >>> * ch_params: video standard configuration parameters for vpif >>> @@ -439,19 +438,15 @@ static int vpif_probe(struct platform_device *pdev) >>> goto fail; >>> } >>> >>> - vpif_clk = clk_get(&pdev->dev, "vpif"); >>> - if (IS_ERR(vpif_clk)) { >>> - status = PTR_ERR(vpif_clk); >>> - goto clk_fail; >>> - } >>> - clk_prepare_enable(vpif_clk); >>> + pm_runtime_enable(&pdev->dev); >>> + pm_runtime_resume(&pdev->dev); >>> + >>> + pm_runtime_get(&pdev->dev); >> >> I don't see runtime-pm ops being registered. Can you explain how clock >> prepare/unprepare is taken care by runtime-pm? >> > The pm_runtime API handles the clock management for you. > For Davinci platform runtime PM support for clock management has > been added (You can find it in arch/arm/mach-davinci/pm_domain.c) > When runtime PM is enabled, the davinci runtime PM implementation will > use the pm_clk layer to enable/disable clocks on demand. I see. Thanks for the explanation. > > For more/detailed understanding you can go through the pm_runtime framework. > > Regards, > --Prabhakar -- Regards, Rajagopal -- 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/