Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758322Ab3DAIX0 (ORCPT ); Mon, 1 Apr 2013 04:23:26 -0400 Received: from mail-wg0-f54.google.com ([74.125.82.54]:41318 "EHLO mail-wg0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758308Ab3DAIXW (ORCPT ); Mon, 1 Apr 2013 04:23:22 -0400 MIME-Version: 1.0 In-Reply-To: References: <1364798210-31517-1-git-send-email-prabhakar.csengg@gmail.com> From: Prabhakar Lad Date: Mon, 1 Apr 2013 13:53:01 +0530 Message-ID: Subject: Re: [PATCH v2] davinci: vpif: add pm_runtime support To: Rajagopal Venkat 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: 2768 Lines: 75 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. For more/detailed understanding you can go through the pm_runtime framework. Regards, --Prabhakar -- 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/