Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752484AbdIXNKg (ORCPT ); Sun, 24 Sep 2017 09:10:36 -0400 Received: from fllnx209.ext.ti.com ([198.47.19.16]:43323 "EHLO fllnx209.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752347AbdIXNKe (ORCPT ); Sun, 24 Sep 2017 09:10:34 -0400 Subject: Re: [PATCH v3 5/5] mtd: spi-nor: cadence-quadspi: Add runtime PM support To: Marek Vasut , Cyrille Pitchen CC: David Woodhouse , Brian Norris , Boris Brezillon , Rob Herring , , , , linux-arm-kernel References: <20170924105924.23923-1-vigneshr@ti.com> <20170924105924.23923-6-vigneshr@ti.com> <3a1160f9-a0ae-c84c-d209-af97c3c3b0f6@gmail.com> From: Vignesh R Message-ID: <4ee69ea4-14cc-4305-bf3f-8fe76d43bf6b@ti.com> Date: Sun, 24 Sep 2017 18:38:23 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.3.0 MIME-Version: 1.0 In-Reply-To: <3a1160f9-a0ae-c84c-d209-af97c3c3b0f6@gmail.com> Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1955 Lines: 64 On 9/24/2017 5:31 PM, Marek Vasut wrote: > On 09/24/2017 12:59 PM, Vignesh R wrote: >> Add pm_runtime* calls to cadence-quadspi driver. This is required to >> switch on QSPI power domain on TI 66AK2G SoC during probe. >> >> Signed-off-by: Vignesh R > > Are you planning to add some more fine-grained PM control later? Yes, I will need to add fine-grained PM control at some point. But, for now SoC does not really support low power mode or runtime power saving option. The fact that driver still uses clk_prepare_*() calls to enable/disable clocks instead of pm_*() calls makes it a bit tricky though. Just figured out I forgot to add cleanup code in error handling path of probe(). Will fix that and send a v4. > >> --- >> drivers/mtd/spi-nor/cadence-quadspi.c | 11 +++++++++++ >> 1 file changed, 11 insertions(+) >> >> diff --git a/drivers/mtd/spi-nor/cadence-quadspi.c b/drivers/mtd/spi-nor/cadence-quadspi.c >> index d9629e8f4798..2c8e6226d267 100644 >> --- a/drivers/mtd/spi-nor/cadence-quadspi.c >> +++ b/drivers/mtd/spi-nor/cadence-quadspi.c >> @@ -31,6 +31,7 @@ >> #include >> #include >> #include >> +#include >> #include >> #include >> #include >> @@ -1224,6 +1225,13 @@ static int cqspi_probe(struct platform_device *pdev) >> return -ENXIO; >> } >> >> + pm_runtime_enable(&pdev->dev); >> + ret = pm_runtime_get_sync(&pdev->dev); >> + if (ret < 0) { >> + pm_runtime_put_noidle(&pdev->dev); >> + return ret; >> + } >> + >> ret = clk_prepare_enable(cqspi->clk); >> if (ret) { >> dev_err(dev, "Cannot enable QSPI clock.\n"); >> @@ -1275,6 +1283,9 @@ static int cqspi_remove(struct platform_device *pdev) >> >> clk_disable_unprepare(cqspi->clk); >> >> + pm_runtime_put_sync(&pdev->dev); >> + pm_runtime_disable(&pdev->dev); >> + >> return 0; >> } >> >> > >