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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F083CC433EF for ; Thu, 7 Oct 2021 13:50:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D63F7611EE for ; Thu, 7 Oct 2021 13:50:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241731AbhJGNwN (ORCPT ); Thu, 7 Oct 2021 09:52:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46714 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241816AbhJGNwN (ORCPT ); Thu, 7 Oct 2021 09:52:13 -0400 Received: from mail-lf1-x12d.google.com (mail-lf1-x12d.google.com [IPv6:2a00:1450:4864:20::12d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38277C061570 for ; Thu, 7 Oct 2021 06:50:19 -0700 (PDT) Received: by mail-lf1-x12d.google.com with SMTP id n8so24095914lfk.6 for ; Thu, 07 Oct 2021 06:50:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=1PSfrIbkMTQ1HdGmDy7QPzG/bI9Btr9cDuF+9gXLPAE=; b=WJcJtLiJreWLmywPc2jp3x7not6dDr0Zb7+jZbMu+bWuqy4CQD/T3UUOGUcCeCw9zi NlLPt1pc4hPvAERDYQqi7OqvDA/x6ZTGOJiJx+mVIThSTo+uwEo2JsqS1H03ep7zsjSx CNbSY6/nmMaYFqV6RvkZAARfhAlh1iDP9Xdk+zknkF7iX/tCLyHhbAQsHj9wD82Z3aqQ 3Z/3XOTm6a6KzJvyj27+bbB24s53yzF1w/EUnLQFLwGi9SeY8R2Ke7Fh9cW4RM5sC2yn R2fufhRigyfO9BLiacU45nLiwd0pPeSXIVZHmNEZ1kyBUHxtwVfYjepQanegfMQ/4+36 2FEA== 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:mime-version :content-transfer-encoding; bh=1PSfrIbkMTQ1HdGmDy7QPzG/bI9Btr9cDuF+9gXLPAE=; b=KR38gsOVkGJSKsQx4qZAVRJU0azZ8oku+Qo0HmkUu0uLk+nAzl4jMFWO8ycZU/8Lpq Rs0FFuwyYTQ8MCFaZdOxF022EY4Otj+7N/akB3GpbZ97dJiMm3fLujtEHZJza6EtfHXn Wny38cNGMkiztv0N+eIJnqI1eO3W4S4qgFcQqasNJjvRqwqiZeCb8OeKYegt4TuUFBw0 sbt48q+6GcRreNoIj5M0oQHGzPeHOOI821teFZqGTycOqHffCONHD13XPdVFm//iRS9a qIaITzIARmS0O5RIbaTab92XMyx9CsrB1buLhnyHldjTTPATegUF94PnjIxHYfXrup1X I9wg== X-Gm-Message-State: AOAM530Qbcn5cGm0k8+oL0rtRncSx5UgljtEBqPd71GDRBzdtBOMzgls I9DOHWGaR7CEZzX1/g4LVnO3cA== X-Google-Smtp-Source: ABdhPJyhApVyHPK1Cwqr4udEJhbfha3UuzSWVDodocsqtXvf7OgkWfBfR885j3TLc7K5GzItI7BksQ== X-Received: by 2002:a05:651c:1025:: with SMTP id w5mr4038161ljm.282.1633614605590; Thu, 07 Oct 2021 06:50:05 -0700 (PDT) Received: from localhost ([31.134.121.151]) by smtp.gmail.com with ESMTPSA id q14sm1111160lfe.118.2021.10.07.06.50.04 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Oct 2021 06:50:04 -0700 (PDT) From: Sam Protsenko To: Michael Turquette , Stephen Boyd , Russell King Cc: Chanwoo Choi , Sylwester Nawrocki , Krzysztof Kozlowski , Mike Tipton , Andy Shevchenko , Andy Shevchenko , Geert Uytterhoeven , linux-clk@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] clk: Add clk_set_parent debugfs node Date: Thu, 7 Oct 2021 16:50:03 +0300 Message-Id: <20211007135003.2229-1-semen.protsenko@linaro.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Useful for testing mux clocks. One can write the index of the parent to set into clk_parent node, starting from 0. Example # cd /sys/kernel/debug/clk/mout_peri_bus # cat clk_possible_parrents dout_shared0_div4 dout_shared1_div4 # cat clk_parent dout_shared0_div4 # echo 1 > clk_parent # cat clk_parent dout_shared1_div4 One needs to define CLOCK_ALLOW_WRITE_DEBUGFS in drivers/clk/clk.c in order to use this feature. Signed-off-by: Sam Protsenko --- Changes in v2: - Merged write() function into existing 'clk_parent' file - Removed 'if (val >= core->num_parents)' check - Removed incorrect usage of IS_ERR_OR_NULL() drivers/clk/clk.c | 56 +++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 54 insertions(+), 2 deletions(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 806c55f0991b..5776efab4739 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -3224,6 +3224,46 @@ static int current_parent_show(struct seq_file *s, void *data) } DEFINE_SHOW_ATTRIBUTE(current_parent); +#ifdef CLOCK_ALLOW_WRITE_DEBUGFS +static ssize_t current_parent_write(struct file *file, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct seq_file *s = file->private_data; + struct clk_core *core = s->private; + struct clk_core *parent; + char buf[4] = { 0 }; + u8 idx; + int err; + + if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count))) + return -EFAULT; + + err = kstrtou8(buf, 0, &idx); + if (err) + return err; + + parent = clk_core_get_parent_by_index(core, idx); + if (!parent) + return -ENOENT; + + clk_prepare_lock(); + err = clk_core_set_parent_nolock(core, parent); + clk_prepare_unlock(); + if (err) + return err; + + return count; +} + +static const struct file_operations current_parent_rw_fops = { + .open = current_parent_open, + .write = current_parent_write, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; +#endif + static int clk_duty_cycle_show(struct seq_file *s, void *data) { struct clk_core *core = s->private; @@ -3291,13 +3331,25 @@ static void clk_debug_create_one(struct clk_core *core, struct dentry *pdentry) &clk_prepare_enable_fops); #endif - if (core->num_parents > 0) + if (core->num_parents > 0) { +#ifdef CLOCK_ALLOW_WRITE_DEBUGFS + if (core->num_parents > 1) { + debugfs_create_file("clk_parent", 0644, root, core, + ¤t_parent_rw_fops); + } else { + debugfs_create_file("clk_parent", 0444, root, core, + ¤t_parent_fops); + } +#else debugfs_create_file("clk_parent", 0444, root, core, ¤t_parent_fops); +#endif + } - if (core->num_parents > 1) + if (core->num_parents > 1) { debugfs_create_file("clk_possible_parents", 0444, root, core, &possible_parents_fops); + } if (core->ops->debug_init) core->ops->debug_init(core->hw, core->dentry); -- 2.30.2