From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_NEOMUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2EFD5C43387 for ; Mon, 7 Jan 2019 13:29:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 07430206B6 for ; Mon, 7 Jan 2019 13:29:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727147AbfAGN3c (ORCPT ); Mon, 7 Jan 2019 08:29:32 -0500 Received: from mail.bootlin.com ([62.4.15.54]:38998 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726886AbfAGN3c (ORCPT ); Mon, 7 Jan 2019 08:29:32 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id BBC0620746; Mon, 7 Jan 2019 14:29:29 +0100 (CET) Received: from localhost (aaubervilliers-681-1-29-148.w90-88.abo.wanadoo.fr [90.88.149.148]) by mail.bootlin.com (Postfix) with ESMTPSA id 8A1C420712; Mon, 7 Jan 2019 14:29:29 +0100 (CET) Date: Mon, 7 Jan 2019 14:29:29 +0100 From: Maxime Ripard To: Jagan Teki Cc: Yong Deng , Mauro Carvalho Chehab , Rob Herring , Mark Rutland , Chen-Yu Tsai , linux-media , linux-arm-kernel , devicetree , linux-kernel , linux-sunxi , linux-amarula@amarulasolutions.com, Michael Trimarchi Subject: Re: [PATCH v5 2/6] media: sun6i: Add mod_rate quirk Message-ID: <20190107132929.ksyajmzn2gzr6oep@flea> References: <20181220125438.11700-1-jagan@amarulasolutions.com> <20181220125438.11700-3-jagan@amarulasolutions.com> <20181221130025.lbvw7yvy74brf3jn@flea> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="5v667uexziqiuyca" Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20180716 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org --5v667uexziqiuyca Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Dec 24, 2018 at 08:57:48PM +0530, Jagan Teki wrote: > On Fri, Dec 21, 2018 at 6:30 PM Maxime Ripard = wrote: > > > > On Thu, Dec 20, 2018 at 06:24:34PM +0530, Jagan Teki wrote: > > > Unfortunately default CSI_SCLK rate cannot work properly to > > > drive the connected sensor interface, particularly on few > > > Allwinner SoC's like A64. > > > > > > So, add mod_rate quirk via driver data so-that the respective > > > SoC's which require to alter the default mod clock rate can assign > > > the operating clock rate. > > > > > > Signed-off-by: Jagan Teki > > > --- > > > .../platform/sunxi/sun6i-csi/sun6i_csi.c | 34 +++++++++++++++--= -- > > > 1 file changed, 28 insertions(+), 6 deletions(-) > > > > > > diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c b/dri= vers/media/platform/sunxi/sun6i-csi/sun6i_csi.c > > > index ee882b66a5ea..fe002beae09c 100644 > > > --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c > > > +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c > > > @@ -15,6 +15,7 @@ > > > #include > > > #include > > > #include > > > +#include > > > #include > > > #include > > > #include > > > @@ -28,8 +29,13 @@ > > > > > > #define MODULE_NAME "sun6i-csi" > > > > > > +struct sun6i_csi_variant { > > > + unsigned long mod_rate; > > > +}; > > > + > > > struct sun6i_csi_dev { > > > struct sun6i_csi csi; > > > + const struct sun6i_csi_variant *variant; > > > struct device *dev; > > > > > > struct regmap *regmap; > > > @@ -822,33 +828,43 @@ static int sun6i_csi_resource_request(struct su= n6i_csi_dev *sdev, > > > return PTR_ERR(sdev->clk_mod); > > > } > > > > > > + if (sdev->variant->mod_rate) > > > + clk_set_rate_exclusive(sdev->clk_mod, sdev->variant->mo= d_rate); > > > + > > > > It still doesn't make any sense to do it in the probe function... >=20 > I'm not sure we discussed about the context wrt probe, we discussed > about exclusive put clock. https://lkml.org/lkml/2018/12/18/584 "Doing it here is not really optimal either, since you'll put a constraint on the system (maintaining that clock at 300MHz), while it's not in use." > Since clocks were enabling in set_power and clock rate can be set > during probe in single time instead of setting it in set_power for > every power enablement. anything wrong with that. See above. Plus, a clock running draws power. It doesn't really make sense to draw power for something that is unused. > > We discussed this in the previous iteration already. > > > > What we didn't discuss is the variant function that you introduce, > > while the previous approach was enough. >=20 > We discussed about clk_rate_exclusive_put, and that even handle it in > .remove right? so I have variant to handle it in sun6i_csi_remove. We indeed discussed the clk_rate_exclusive_put. However, you chose to implement it using a variant structure which really isn't needed. Maxime --=20 Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com --5v667uexziqiuyca Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQRcEzekXsqa64kGDp7j7w1vZxhRxQUCXDNUOQAKCRDj7w1vZxhR xRZxAQD5/B5s/jOZrufS8W1yFw9lVX40DlhFzemEGBkDiUx8SQEAxgnPGYhbrw0Z uyF5vffAm1ff/2MAcEH/OPMiJIPxFQ8= =p7sH -----END PGP SIGNATURE----- --5v667uexziqiuyca--