From patchwork Thu Mar 16 20:20:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 13178297 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 D6A67C6FD1F for ; Thu, 16 Mar 2023 20:21:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230088AbjCPUVW (ORCPT ); Thu, 16 Mar 2023 16:21:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229897AbjCPUVV (ORCPT ); Thu, 16 Mar 2023 16:21:21 -0400 Received: from mail-pj1-x102d.google.com (mail-pj1-x102d.google.com [IPv6:2607:f8b0:4864:20::102d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B76207E89F for ; Thu, 16 Mar 2023 13:21:19 -0700 (PDT) Received: by mail-pj1-x102d.google.com with SMTP id rj10so2841214pjb.4 for ; Thu, 16 Mar 2023 13:21:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1678998079; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=q3i1too33EMahveRbuxNasAN0FfHWaolQncNRUeKk3s=; b=R9oM9aXd2Sn6h4bV0qBQKGi1qHrcdBjSrcHuV+y6QBP/Jn6Z911RI6cVBP4wJ1wcul rKxVuPuEEl3ZQBPkJUSgcVFGOOI5sgLW3w8gFyX3MGy9Ic7dOJmAAFMogXNEFs+xSDWW 4zBkSHGamxKFL+TaLmsN3X1dZON4TpUUMMhtE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678998079; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=q3i1too33EMahveRbuxNasAN0FfHWaolQncNRUeKk3s=; b=WdQAPiGJh0sgKIT7bILrCemzvE/wRlJiWhNW+ws5mr6uoCxkBpeuy4KNwSze7+lNbl tr+tyFga/rfImTb6RzRBoemB9Nd3WJnZhIZqTRNxkCPlKV7YjCn/pi6YueCvWrWIiRYT z1OtIYGNRtVA+TbwcKnOTYCve2H9R24ZXl7XRZCXVrEUzifEHRGH9XRgVAverWwUpq58 auJQaeVy75nicugUskxTEkaADu1Tpli+hDK64PqBZ7AChbYVA8f9oVd8Bp6FVP3Jg/7a SsgGRur1AdxXU+O9UtMe7ao/UqKt6t0qHAsrle06YPHjvv5R1LvN3e6ZyrNbrCTPUpAt YzKA== X-Gm-Message-State: AO0yUKX2zrnpUuh4AhaK0kosJzLSl2FBeuRAQbLKvQ/X001wB6l7ef0s XLe7Z2Iyav98pnNZyf50uw+Ylw== X-Google-Smtp-Source: AK7set9yssgAFQezxJ/RfIneXy6O9/6hx6IWvENqFQh8FK49jmaaVVUPU6K/d3qqZDHF4VNoOI1Xyg== X-Received: by 2002:a17:90b:350f:b0:23f:35c8:895 with SMTP id ls15-20020a17090b350f00b0023f35c80895mr2925707pjb.32.1678998079225; Thu, 16 Mar 2023 13:21:19 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:4db6:6f23:6ad2:998d]) by smtp.gmail.com with ESMTPSA id b4-20020a17090a5a0400b0023acdac248dsm24114pjd.15.2023.03.16.13.21.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Mar 2023 13:21:18 -0700 (PDT) From: Douglas Anderson To: Bjorn Andersson , Greg Kroah-Hartman Cc: linux-arm-msm@vger.kernel.org, Jiri Slaby , Bartosz Golaszewski , Daniel Thompson , kgdb-bugreport@lists.sourceforge.net, Konrad Dybcio , linux-serial@vger.kernel.org, Douglas Anderson , Andy Gross , linux-kernel@vger.kernel.org Subject: [RESEND PATCH 0/2] tty: serial: Fix kgdb on qcom-geni-serial when no other UART users Date: Thu, 16 Mar 2023 13:20:55 -0700 Message-Id: <20230316202057.4070382-1-dianders@chromium.org> X-Mailer: git-send-email 2.40.0.rc1.284.g88254d51c5-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Today to get kgdb to work on qcom-geni-serial devices you need _something_ to init/power on the UART. This could either the kernel console output or an "agetty" running on the port. If nothing else powers the port then you'll end up getting a silent hang when you try to enter kgdb. Let's fix this. The first patch here is for the tty layer to make sure that we power on the port when we init it for polling. This would be important for any drivers similar to qcom-geni-serial that actually need to be powered on. The second patch here hooks up the poll_init() function for qcom-geni-serial, leveraging an existing function in the driver that does everything we need. Originally these two patches were bundled together as pathes 2 and 3 of a 3-patch series. We no longer need the first patch from the orginal series since we landed a similar patch from Johan [1] instead. The second two patches are still useful, though, so I've reposted them alone and added this cover letter. [1] https://lore.kernel.org/r/20230307164405.14218-1-johan+linaro@kernel.org Douglas Anderson (2): serial: uart_poll_init() should power on the UART tty: serial: qcom-geni-serial: Add a poll_init() function drivers/tty/serial/qcom_geni_serial.c | 1 + drivers/tty/serial/serial_core.c | 6 ++++++ 2 files changed, 7 insertions(+)