From patchwork Fri Jun 9 14:39:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Miquel Raynal X-Patchwork-Id: 13274052 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 46673C7EE2E for ; Fri, 9 Jun 2023 14:39:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241420AbjFIOjV (ORCPT ); Fri, 9 Jun 2023 10:39:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57742 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241079AbjFIOjU (ORCPT ); Fri, 9 Jun 2023 10:39:20 -0400 Received: from relay3-d.mail.gandi.net (relay3-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::223]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99EAC269A; Fri, 9 Jun 2023 07:39:18 -0700 (PDT) X-GND-Sasl: miquel.raynal@bootlin.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1686321557; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O/Gbxig3KHx3alSZjtr0kx9eZgIqHD/LRBPLbP6Mt5Y=; b=BibnEOww0QBNScennSR5DSp34xDnk2kE/9mj92EqUnNRVtVhgZ0wNtltmPLBjVh9VzQKvS C7fQ94nAoXDPc68JADBWh4uSPJnzTe6UVeYV6XNx2/NPOKCHiwthna5sDYgg4IaEUlmTK9 rnPIgMEkgUi8uv38t662BswGdGk9DlX6y36e9BzGVAFbOgBlLLm+EOSc4Jzqt4nLjEc8Rq GOUt7LOEplO804qtYUWiVW1Btf2DrYlvw9sU5WrVf1do8jFS8tXOt+NWlfHHM/hmThhZBx BjJ25cjuTT1BCrHU/8kDKbZrBeqNuwBY+AW/Gg/EFzCdIkEojRegwJCSqk+hYw== X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com X-GND-Sasl: miquel.raynal@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPSA id 3139A60009; Fri, 9 Jun 2023 14:39:16 +0000 (UTC) From: Miquel Raynal To: Nicolas Ferre , Alexandre Belloni , Claudiu Beznea Cc: , , linux-pm@vger.kernel.org, Thomas Petazzoni , Kamel Bouhara , Miquel Raynal Subject: [PATCH 2/2] power: reset: at91-reset: add sysfs interface to the power on reason Date: Fri, 9 Jun 2023 16:39:12 +0200 Message-Id: <20230609143912.849995-3-miquel.raynal@bootlin.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230609143912.849995-1-miquel.raynal@bootlin.com> References: <20230609143912.849995-1-miquel.raynal@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org From: Kamel Bouhara Introduce a list of generic reset sources and use them to export the power on reason through sysfs. Update the ABI documentation to describe this new interface. Signed-off-by: Kamel Bouhara Acked-by: Nicolas Ferre [Miquel Raynal: Follow-up on Kamel's work, 4 years later] Signed-off-by: Miquel Raynal --- .../testing/sysfs-platform-power-on-reason | 10 +++++ drivers/power/reset/at91-reset.c | 42 +++++++++++++------ include/linux/power/power_on_reason.h | 19 +++++++++ 3 files changed, 59 insertions(+), 12 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-platform-power-on-reason create mode 100644 include/linux/power/power_on_reason.h diff --git a/Documentation/ABI/testing/sysfs-platform-power-on-reason b/Documentation/ABI/testing/sysfs-platform-power-on-reason new file mode 100644 index 000000000000..12020d017543 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-platform-power-on-reason @@ -0,0 +1,10 @@ +What: /sys/devices/platform/.../power_on_reason +Date: October 2019 +KernelVersion: 5.4 +Contact: Kamel Bouhara +Description: This file shows system power on reason. Possible sources are: + General system power-on, RTC wakeup, watchdog timeout, software + reset, user pressed reset button, CPU clock failure, oscillator + failure, low power mode exit, unknown. + + The file is read only. diff --git a/drivers/power/reset/at91-reset.c b/drivers/power/reset/at91-reset.c index a8a6f3997768..73cc6839a1c1 100644 --- a/drivers/power/reset/at91-reset.c +++ b/drivers/power/reset/at91-reset.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include @@ -149,44 +150,54 @@ static int at91_reset(struct notifier_block *this, unsigned long mode, return NOTIFY_DONE; } -static void __init at91_reset_status(struct at91_reset *reset) +static const char *at91_reset_reason(struct at91_reset *reset) { u32 reg = readl(reset->rstc_base + AT91_RSTC_SR); const char *reason; switch ((reg & AT91_RSTC_RSTTYP) >> 8) { case RESET_TYPE_GENERAL: - reason = "general reset"; + reason = POWER_ON_REASON_GENERAL; break; case RESET_TYPE_WAKEUP: - reason = "wakeup"; + reason = POWER_ON_REASON_RTC; break; case RESET_TYPE_WATCHDOG: - reason = "watchdog reset"; + reason = POWER_ON_REASON_WATCHDOG; break; case RESET_TYPE_SOFTWARE: - reason = "software reset"; + reason = POWER_ON_REASON_SOFTWARE; break; case RESET_TYPE_USER: - reason = "user reset"; + reason = POWER_ON_REASON_USER; break; case RESET_TYPE_CPU_FAIL: - reason = "CPU clock failure detection"; + reason = POWER_ON_REASON_CPU_FAIL; break; case RESET_TYPE_XTAL_FAIL: - reason = "32.768 kHz crystal failure detection"; + reason = POWER_ON_REASON_XTAL_FAIL; break; case RESET_TYPE_ULP2: - reason = "ULP2 reset"; + reason = POWER_ON_REASON_LOW_POWER; break; default: - reason = "unknown reset"; + reason = POWER_ON_REASON_UNKNOWN; break; } - dev_info(&pdev->dev, "Starting after %s\n", reason); + return reason; } +static ssize_t power_on_reason_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct platform_device *pdev = to_platform_device(dev); + struct at91_reset *reset = platform_get_drvdata(pdev); + + return sprintf(buf, "%s\n", at91_reset_reason(reset)); +} +static DEVICE_ATTR_RO(power_on_reason); + static const struct of_device_id at91_ramc_of_match[] = { { .compatible = "atmel,at91sam9260-sdramc", @@ -391,7 +402,14 @@ static int __init at91_reset_probe(struct platform_device *pdev) if (ret) goto disable_clk; - at91_reset_status(pdev, reset->rstc_base); + ret = device_create_file(&pdev->dev, &dev_attr_power_on_reason); + if (ret) { + dev_err(&pdev->dev, "Could not create sysfs entry\n"); + return ret; + } + + dev_info(&pdev->dev, "Starting after %s reset\n", + at91_reset_reason(reset)); return 0; diff --git a/include/linux/power/power_on_reason.h b/include/linux/power/power_on_reason.h new file mode 100644 index 000000000000..4b92eb0519c4 --- /dev/null +++ b/include/linux/power/power_on_reason.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Author: Kamel Bouhra + */ + +#ifndef POWER_ON_REASON_H +#define POWER_ON_REASON_H + +#define POWER_ON_REASON_GENERAL "general" +#define POWER_ON_REASON_RTC "RTC wakeup" +#define POWER_ON_REASON_WATCHDOG "watchdog timeout" +#define POWER_ON_REASON_SOFTWARE "software" +#define POWER_ON_REASON_USER "user" +#define POWER_ON_REASON_CPU_FAIL "CPU clock failure" +#define POWER_ON_REASON_XTAL_FAIL "crystal oscillator failure" +#define POWER_ON_REASON_LOW_POWER "low power exit" +#define POWER_ON_REASON_UNKNOWN "unknown" + +#endif /* POWER_ON_REASON_H */