From patchwork Mon Dec 13 15:26:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Biju Das X-Patchwork-Id: 523623 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 CB1B3C433FE for ; Mon, 13 Dec 2021 15:27:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240090AbhLMP1K (ORCPT ); Mon, 13 Dec 2021 10:27:10 -0500 Received: from relmlor1.renesas.com ([210.160.252.171]:60167 "EHLO relmlie5.idc.renesas.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S234672AbhLMP1K (ORCPT ); Mon, 13 Dec 2021 10:27:10 -0500 X-IronPort-AV: E=Sophos;i="5.88,202,1635174000"; d="scan'208";a="103326604" Received: from unknown (HELO relmlir5.idc.renesas.com) ([10.200.68.151]) by relmlie5.idc.renesas.com with ESMTP; 14 Dec 2021 00:27:09 +0900 Received: from localhost.localdomain (unknown [10.226.92.170]) by relmlir5.idc.renesas.com (Postfix) with ESMTP id 74CB740078D4; Tue, 14 Dec 2021 00:27:07 +0900 (JST) From: Biju Das To: Wim Van Sebroeck , Guenter Roeck Cc: Biju Das , linux-watchdog@vger.kernel.org, Geert Uytterhoeven , Chris Paterson , Biju Das , Prabhakar Mahadev Lad , linux-renesas-soc@vger.kernel.org Subject: [PATCH v2 3/4] watchdog: rzg2l_wdt: Add set_timeout callback Date: Mon, 13 Dec 2021 15:26:57 +0000 Message-Id: <20211213152658.26225-3-biju.das.jz@bp.renesas.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211213152658.26225-1-biju.das.jz@bp.renesas.com> References: <20211213152658.26225-1-biju.das.jz@bp.renesas.com> Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org Once watchdog is started, WDT cycle setting register(WDTSET) cannot be changed. However we can reconfigure the new value for WDSET, after a module reset. Otherwise it will ignore the writes and will hold the previous value instead of the updated one. This patch add support for set_timeout callback by doing module reset, which allows us to update WDTSET register. Based on the watchdog timer state, it may restart WDT with the modified values. Signed-off-by: Biju Das --- V1->V2: * Updated commit description * Removed stop/start and started using reset() instead. * After reset, Start WDT based on watchdog timer state. --- drivers/watchdog/rzg2l_wdt.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/drivers/watchdog/rzg2l_wdt.c b/drivers/watchdog/rzg2l_wdt.c index 0e62d7be153c..d1b5cb70d56c 100644 --- a/drivers/watchdog/rzg2l_wdt.c +++ b/drivers/watchdog/rzg2l_wdt.c @@ -110,6 +110,33 @@ static int rzg2l_wdt_stop(struct watchdog_device *wdev) return reset_control_reset(priv->rstc); } +static int rzg2l_wdt_set_timeout(struct watchdog_device *wdev, unsigned int timeout) +{ + struct rzg2l_wdt_priv *priv = watchdog_get_drvdata(wdev); + int ret; + + wdev->timeout = timeout; + + /* + * We need to reset the module for updating WDTSET register + * If watchdog is active, then decrement the PM counter to make + * it balanced, after reset operation. + */ + if (watchdog_active(wdev)) + pm_runtime_put(wdev->parent); + + /* Reset the module for updating WDTSET register */ + ret = reset_control_reset(priv->rstc); + if (watchdog_active(wdev)) { + if (ret) + pm_runtime_get_sync(wdev->parent); + else + rzg2l_wdt_start(wdev); + } + + return ret; +} + static int rzg2l_wdt_restart(struct watchdog_device *wdev, unsigned long action, void *data) { @@ -153,6 +180,7 @@ static const struct watchdog_ops rzg2l_wdt_ops = { .start = rzg2l_wdt_start, .stop = rzg2l_wdt_stop, .ping = rzg2l_wdt_ping, + .set_timeout = rzg2l_wdt_set_timeout, .restart = rzg2l_wdt_restart, };