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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF9A4CDB47E for ; Sun, 15 Oct 2023 12:49:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229850AbjJOMtb (ORCPT ); Sun, 15 Oct 2023 08:49:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60228 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229555AbjJOMt3 (ORCPT ); Sun, 15 Oct 2023 08:49:29 -0400 Received: from honk.sigxcpu.org (honk.sigxcpu.org [24.134.29.49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C60CBAB for ; Sun, 15 Oct 2023 05:49:27 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by honk.sigxcpu.org (Postfix) with ESMTP id 5C9B7FB03; Sun, 15 Oct 2023 14:49:24 +0200 (CEST) Received: from honk.sigxcpu.org ([127.0.0.1]) by localhost (honk.sigxcpu.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QmGYZ04xXnHb; Sun, 15 Oct 2023 14:49:23 +0200 (CEST) Date: Sun, 15 Oct 2023 14:49:20 +0200 From: Guido =?iso-8859-1?Q?G=FCnther?= To: Frank Oltmanns Cc: Purism Kernel Team , Ondrej Jirman , Thierry Reding , Sam Ravnborg , David Airlie , Daniel Vetter , "open list:DRM PANEL DRIVERS" , open list , phone-devel@vger.kernel.org, Ondrej Jirman , Samuel Holland Subject: Re: [PATCH 1/1] drm/panel: st7703: Pick different reset sequence Message-ID: References: <20230211171748.36692-1-frank@oltmanns.dev> <20230211171748.36692-2-frank@oltmanns.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230211171748.36692-2-frank@oltmanns.dev> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Sat, Feb 11, 2023 at 06:17:48PM +0100, Frank Oltmanns wrote: > From: Ondrej Jirman > > Switching to a different reset sequence, enabling IOVCC before enabling > VCC. > > There also needs to be a delay after enabling the supplies and before > deasserting the reset. The datasheet specifies 1ms after the supplies > reach the required voltage. Use 10-20ms to also give the power supplies > some time to reach the required voltage, too. > > This fixes intermittent panel initialization failures and screen > corruption during resume from sleep on panel xingbangda,xbd599 (e.g. > used in PinePhone). Thanks, applied to drm-misc-next. Cheers, -- Guido > > Signed-off-by: Ondrej Jirman > Signed-off-by: Frank Oltmanns > Reported-by: Samuel Holland > --- > drivers/gpu/drm/panel/panel-sitronix-st7703.c | 25 ++++++++++--------- > 1 file changed, 13 insertions(+), 12 deletions(-) > > diff --git a/drivers/gpu/drm/panel/panel-sitronix-st7703.c b/drivers/gpu/drm/panel/panel-sitronix-st7703.c > index 6747ca237ced..45695aa51f62 100644 > --- a/drivers/gpu/drm/panel/panel-sitronix-st7703.c > +++ b/drivers/gpu/drm/panel/panel-sitronix-st7703.c > @@ -411,29 +411,30 @@ static int st7703_prepare(struct drm_panel *panel) > return 0; > > dev_dbg(ctx->dev, "Resetting the panel\n"); > - ret = regulator_enable(ctx->vcc); > + gpiod_set_value_cansleep(ctx->reset_gpio, 1); > + > + ret = regulator_enable(ctx->iovcc); > if (ret < 0) { > - dev_err(ctx->dev, "Failed to enable vcc supply: %d\n", ret); > + dev_err(ctx->dev, "Failed to enable iovcc supply: %d\n", ret); > return ret; > } > - ret = regulator_enable(ctx->iovcc); > + > + ret = regulator_enable(ctx->vcc); > if (ret < 0) { > - dev_err(ctx->dev, "Failed to enable iovcc supply: %d\n", ret); > - goto disable_vcc; > + dev_err(ctx->dev, "Failed to enable vcc supply: %d\n", ret); > + regulator_disable(ctx->iovcc); > + return ret; > } > > - gpiod_set_value_cansleep(ctx->reset_gpio, 1); > - usleep_range(20, 40); > + /* Give power supplies time to stabilize before deasserting reset. */ > + usleep_range(10000, 20000); > + > gpiod_set_value_cansleep(ctx->reset_gpio, 0); > - msleep(20); > + usleep_range(15000, 20000); > > ctx->prepared = true; > > return 0; > - > -disable_vcc: > - regulator_disable(ctx->vcc); > - return ret; > } > > static const u32 mantix_bus_formats[] = { > -- > 2.39.1 >