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 80DFCC77B76 for ; Thu, 20 Apr 2023 14:04:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231839AbjDTOEU (ORCPT ); Thu, 20 Apr 2023 10:04:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230025AbjDTOES (ORCPT ); Thu, 20 Apr 2023 10:04:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B478E211C; Thu, 20 Apr 2023 07:04:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4F181618A0; Thu, 20 Apr 2023 14:04:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51E96C433D2; Thu, 20 Apr 2023 14:04:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1681999451; bh=DKXKKNzEalaFBkkihjSMZq+RvsASzGcDEcH47uE9AYY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=oBmM9k13zDUPAdsg//VtLRSGpfj0tQr2v3AlXFCbQGggXl/DkSOT6J7rVERFRk/Tm FAZm65zkPjhESgz9Wt0sYCVmyi+CHn90SLjbmFX6hRWvFryL5Vum6ak2piaYIsPECT 9gOBstmPrUZxPTeP5vSrtmdNadUXhEvuQQiDDu5zZubUAMzC5jHNUMp2QuOw/3FT1Q Uscg8X7RCiT6FaijaLTqLy+JMAXmvCHMnZ9wmw8pfaNCn8FwcnvLepr4ndPlci74Co tN85M0v7ldp2EZ+sPI5yVo7zwD0w+4fqBCHWEeeZj9rGJkmHmNfUN9ImTeFRTexU1Z 7IIigbC+cdBMA== Date: Thu, 20 Apr 2023 15:04:06 +0100 From: Lee Jones To: Benjamin Bara Cc: Wolfram Sang , rafael.j.wysocki@intel.com, dmitry.osipenko@collabora.com, peterz@infradead.org, jonathanh@nvidia.com, richard.leitner@linux.dev, treding@nvidia.com, linux-kernel@vger.kernel.org, linux-i2c@vger.kernel.org, linux-tegra@vger.kernel.org, Benjamin Bara Subject: Re: [PATCH v5 6/6] mfd: tps6586x: register restart handler Message-ID: <20230420140406.GH996918@google.com> References: <20230327-tegra-pmic-reboot-v5-0-ab090e03284d@skidata.com> <20230327-tegra-pmic-reboot-v5-6-ab090e03284d@skidata.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20230327-tegra-pmic-reboot-v5-6-ab090e03284d@skidata.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 18 Apr 2023, Benjamin Bara wrote: > From: Benjamin Bara > > There are a couple of boards which use a tps6586x as > "ti,system-power-controller", e.g. the tegra20-tamonten.dtsi. > For these, the only registered restart handler is the warm reboot via > tegra's PMC. As the bootloader of the tegra20 requires the VDE, it must > be ensured that VDE is enabled (which is the case after a cold reboot). > For the "normal reboot", this is basically the case since 8f0c714ad9be. > However, this workaround is not executed in case of an emergency restart. > In case of an emergency restart, the system now simply hangs in the > bootloader, as VDE is not enabled (because it is not used). > > The TPS658629-Q1 (unfortunately the only TPS6586x with public data sheet) > provides a SOFT RST bit in the SUPPLYENE reg to request a (cold) reboot, > which takes at least 10ms (as the data sheet states). > This avoids the hang-up. > > Tested on a TPS658640. > > Signed-off-by: Benjamin Bara > --- > drivers/mfd/tps6586x.c | 26 ++++++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/drivers/mfd/tps6586x.c b/drivers/mfd/tps6586x.c > index 226e856e34e0..f7665b368071 100644 > --- a/drivers/mfd/tps6586x.c > +++ b/drivers/mfd/tps6586x.c > @@ -30,6 +30,7 @@ > #include > > #define TPS6586X_SUPPLYENE 0x14 > +#define SOFT_RST_BIT BIT(0) > #define EXITSLREQ_BIT BIT(1) > #define SLEEP_MODE_BIT BIT(3) > > @@ -475,6 +476,24 @@ static int tps6586x_power_off_handler(struct sys_off_data *data) > return notifier_from_errno(-ETIME); > } > > +static int tps6586x_restart_handler(struct sys_off_data *data) > +{ > + int ret; > + > + /* tps6586x only provides a hard/cold reboot, skip others. */ TPS6586x > + if (data->mode != REBOOT_UNDEFINED && data->mode != REBOOT_COLD && > + data->mode != REBOOT_HARD) > + return NOTIFY_DONE; > + > + /* bring pmic into HARD REBOOT state. this takes at least 10ms. */ Same as the other patch. > + ret = tps6586x_set_bits(data->dev, TPS6586X_SUPPLYENE, SOFT_RST_BIT); > + if (ret) > + return notifier_from_errno(ret); > + > + mdelay(20); Why 20 here and 50 in the other patch? > + return notifier_from_errno(-ETIME); > +} > + > static void tps6586x_print_version(struct i2c_client *client, int version) > { > const char *name; > @@ -575,6 +594,13 @@ static int tps6586x_i2c_probe(struct i2c_client *client) > dev_err(&client->dev, "register power off handler failed: %d\n", ret); > goto err_add_devs; > } > + > + ret = devm_register_restart_handler(&client->dev, &tps6586x_restart_handler, > + NULL); > + if (ret) { > + dev_err(&client->dev, "register restart handler failed: %d\n", ret); > + goto err_add_devs; > + } > } > > return 0; > > -- > 2.34.1 > -- Lee Jones [李琼斯]