From patchwork Tue Feb 1 17:47:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daniel Thompson X-Patchwork-Id: 12732095 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 48DADC433FE for ; Tue, 1 Feb 2022 17:47:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241676AbiBARrw (ORCPT ); Tue, 1 Feb 2022 12:47:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43082 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241748AbiBARru (ORCPT ); Tue, 1 Feb 2022 12:47:50 -0500 Received: from mail-wr1-x42b.google.com (mail-wr1-x42b.google.com [IPv6:2a00:1450:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 285DEC06173B for ; Tue, 1 Feb 2022 09:47:50 -0800 (PST) Received: by mail-wr1-x42b.google.com with SMTP id e2so33582536wra.2 for ; Tue, 01 Feb 2022 09:47:50 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=7TPcuWXxFU6hWv6NeLAOie1udRWkhLJ1DWe5t2FsQ+M=; b=NuDwlgu6ILp+04FQNgBAsUPzgY4AJ4bWp5fA+81vgbrR5oDX2XCAO6zFTyz1N6KBkU 1kdQkH85xpE2ggU6G7YOsyHHkTToqT8hEBjk5z4lr12RD7yj4VqBh0sdrZL5PnVifknW 4Yd8p3bHKpvTFcIiHl+wEjbshC1kHaYl4TwJhUINoU5P7+NT6/c0K3F2jcQT7LSNe9yy FaXvEgb0ZLMnKx8Bk9pyEz77Z7+wYBdKtsrkqcuuKGXhgjKJySsryv8ltvb/6sadloTy UzkbJtcaH9lrLMA/LhpmdFsKm7icqg8TsZuhhQDF0expi5wKdSPQ3x9ySEnfmKNh7Pkn ccBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=7TPcuWXxFU6hWv6NeLAOie1udRWkhLJ1DWe5t2FsQ+M=; b=rli45C9cvDfsdZDEuOKk94FBzT2h7hqPZrVstDO+fQwOCf/SVyZU2JN+Wu7ALKnj7K XcAv3jSBfsH/QRjE2Q2Ww6yNPysUi8jw/wW50lBwRZ9RAPQNlQqgpl2BGXB/XSpQM3hA 9goOq9fNrtYBGTr/UPC6KELCh+ZmT81a+n6GksLxVCr64OLPg1L58WyIRt2pjrb8/ajK Nsk/FGvGhSVgxjUnQJQWeTAnCNT3MdrL5Ii3IQvlZW1d5YV/WqeIXFIKgxcYYmmtTlEF E/KCFva+Repg0L8RlG4jQv2J7C+Zz/47+/G3514HCdZIRU8MJOVVSYJN5Y5qL8JMUtMW PrAA== X-Gm-Message-State: AOAM532num28C6G2u1CMuk+n5Cg0v/xpYyZ2SYIP1rVAcGuTBb7vl29I t4jCJbTxhRdH8W2m9jWXbo7BOg== X-Google-Smtp-Source: ABdhPJwDJNj1YVlHWPoJ293olzLjFEIQcMbpGy6i0JMKcmYgnDUgr1EqX8iuwkgOa1W/rpbnq/zJPg== X-Received: by 2002:a05:6000:1548:: with SMTP id 8mr21586066wry.504.1643737668657; Tue, 01 Feb 2022 09:47:48 -0800 (PST) Received: from maple.lan (cpc141216-aztw34-2-0-cust174.18-1.cable.virginm.net. [80.7.220.175]) by smtp.gmail.com with ESMTPSA id r2sm3392332wmq.24.2022.02.01.09.47.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Feb 2022 09:47:48 -0800 (PST) From: Daniel Thompson To: Rob Clark , Sean Paul , Abhinav Kumar Cc: Daniel Thompson , David Airlie , Daniel Vetter , linux-arm-msm@vger.kernel.org, dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/2] drm/msm/hdmi: Remove spurious IRQF_ONESHOT flag Date: Tue, 1 Feb 2022 17:47:33 +0000 Message-Id: <20220201174734.196718-3-daniel.thompson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220201174734.196718-1-daniel.thompson@linaro.org> References: <20220201174734.196718-1-daniel.thompson@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Quoting the header comments, IRQF_ONESHOT is "Used by threaded interrupts which need to keep the irq line disabled until the threaded handler has been run.". When applied to an interrupt that doesn't request a threaded irq then IRQF_ONESHOT has a lesser known (undocumented?) side effect, which it to disable the forced threading of irqs. For "normal" kernels if there is no thread_fn then IRQF_ONESHOT is a nop. In this case disabling forced threading is not appropriate because the driver calls wake_up_all() (via msm_hdmi_i2c_irq) and also directly uses the regular spinlock API for locking (in msm_hdmi_hdcp_irq() ). Neither of these APIs can be called from no-thread interrupt handlers on PREEMPT_RT systems. Fix this by removing IRQF_ONESHOT. Signed-off-by: Daniel Thompson Reviewed-by: Dmitry Baryshkov --- drivers/gpu/drm/msm/hdmi/hdmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/hdmi/hdmi.c b/drivers/gpu/drm/msm/hdmi/hdmi.c index 719720709e9e7..e167817b42958 100644 --- a/drivers/gpu/drm/msm/hdmi/hdmi.c +++ b/drivers/gpu/drm/msm/hdmi/hdmi.c @@ -306,7 +306,7 @@ int msm_hdmi_modeset_init(struct hdmi *hdmi, } ret = devm_request_irq(&pdev->dev, hdmi->irq, - msm_hdmi_irq, IRQF_TRIGGER_HIGH | IRQF_ONESHOT, + msm_hdmi_irq, IRQF_TRIGGER_HIGH, "hdmi_isr", hdmi); if (ret < 0) { DRM_DEV_ERROR(dev->dev, "failed to request IRQ%u: %d\n",