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 18B74C433F5 for ; Thu, 7 Oct 2021 13:56:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ED8F0603E9 for ; Thu, 7 Oct 2021 13:56:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241895AbhJGN6j (ORCPT ); Thu, 7 Oct 2021 09:58:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241788AbhJGN6g (ORCPT ); Thu, 7 Oct 2021 09:58:36 -0400 Received: from mail-lf1-x12f.google.com (mail-lf1-x12f.google.com [IPv6:2a00:1450:4864:20::12f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0511FC061746 for ; Thu, 7 Oct 2021 06:56:43 -0700 (PDT) Received: by mail-lf1-x12f.google.com with SMTP id m3so25526016lfu.2 for ; Thu, 07 Oct 2021 06:56:42 -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=4m/QkTKMyjBIG+vcml/nBDmZXoeJ+SJgtqiR6/8Wm88=; b=ebHBt2CXWbsPey4804BoUXNSq5lgNKazryE/pH4AYna5xBGc5X5B19l8mBHxk99N/1 fKFYe7rrCTWd/wE8NyUXhAcF6CWj4Xr2GLUqqzXs+PHsuf/E+9ipHYB2nhhdl3epkJWk P36lEwU9pBTbNPRVwDxLvXu6St9IneQJ7TeJJ5UyUP2rKjDuXG2wZS095Wqod2ENtWrk z2VlmMR5Qsfykhaf09GI/Adn5mW4SNXmPXZ8xW7iSkQU3LpHpeOwoPQchHISE7HzjwZD skyp33+QDiaiFTi6QEivOV1VPQmNhJDrBzYidI7GPwczxREWypPvi2JA2Qu8f9MRlQFD OPtg== 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=4m/QkTKMyjBIG+vcml/nBDmZXoeJ+SJgtqiR6/8Wm88=; b=rO0EveTNsv2Vppy90/U+d6Jxtc6ihe/zJpaqezdOTxLOl27tXbKiZedMdktdKCI2HX m7zARQhfIMsLSYJ4rM+IV/FGgTOTuMEW7RwICoDPcuPlqlgOof1WDqTihqdL83SjvGZP /9QlUBj+O1F63H9wc1bAbxni4T/AXyGJAbDGXucHWlrJOBYxAfet/R0SShn0ZZ2PotPV X3UvUXNC8a59fJ6/LePI6b6Y9WDHEbJzm99mpBo1beP41qKsM4h+Sx2GgUeGsgmqfe2u JMPLNmKd1zdF2UTUB3mHYz0AV8oI07y7nIvxG1kwarZdASjWo0QoGkfvoAxZ+aO/v6O2 PwrA== X-Gm-Message-State: AOAM530e3NqHwxbtO675MzyKJPICFnsecfLQpR1qAPObUajAPLqsIgkc H22MuH8FBPvhUIE/sVMNhnfZig== X-Google-Smtp-Source: ABdhPJwi5WU77cMkLOiS+zG1FLHfIY7fma0J8GJ2CVcd1dpE2WbVt6MjGBYd5y9mfRK+UXcpFEoJbQ== X-Received: by 2002:ac2:44aa:: with SMTP id c10mr4176181lfm.690.1633614997478; Thu, 07 Oct 2021 06:56:37 -0700 (PDT) Received: from localhost ([31.134.121.151]) by smtp.gmail.com with ESMTPSA id m3sm2554419lfh.2.2021.10.07.06.56.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 Oct 2021 06:56:37 -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 v3] clk: Add clk_set_parent debugfs node Date: Thu, 7 Oct 2021 16:56:35 +0300 Message-Id: <20211007135635.2717-1-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-kernel@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 v3: - Removed unwanted changes added by mistake 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 | 53 ++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 52 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 806c55f0991b..f57e33efda9b 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; @@ -3291,9 +3331,20 @@ 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) debugfs_create_file("clk_possible_parents", 0444, root, core, -- 2.30.2