From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 320323FE22; Mon, 12 Feb 2024 17:04:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707757491; cv=none; b=jq9dp7Qt92Po8mQk8FqgWD78dkEer0WtsgPZxIjwHACfS8tjcGkY2vgJba59xMtPV4lX6qXA/fJwEal17yKLhZUJk73dSo89R49qgzmf/3+ORcgP3OUZv3bjuQkIK72V4//LAe0hMzc0nPWqZIozmON61oqP2K1rOhuD9rmGcBA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707757491; c=relaxed/simple; bh=LvC0jNLSvlISq+pfX0tunOut+CloWPeckMMVxbBHVes=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=V3rgEtMKZuVG/l5tR9dhdb1uuJ1DH+cASQn/oUGg4/uL1mAQ8Ii0HUanVAAFe279TkNjOlBHAKvY+D+uZ2+TzNCS3R2BqBMA9ma9OmELGB2YLM69Jq4x2HMvkQgvu9QTcYPs8KeQN6+F+h2XBk+ksewdIzF5FYuyGoyb6nszi2g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=LynqWGE8; arc=none smtp.client-ip=198.175.65.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="LynqWGE8" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1707757491; x=1739293491; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=LvC0jNLSvlISq+pfX0tunOut+CloWPeckMMVxbBHVes=; b=LynqWGE8tHLRz/g63tYhFPvqI082pSK9xAdvxatg9Rpw86Cpf/Rz5+Ng 75UUJhizNmy4peZTrH38RDKpuf/emAp+SU9YJCBiN3QA3z0/o/whpNBmK zhrMUHvgd59yf3EoEyQ3sg07xbv6SaIbWoVcUOFhnArn9jfb4Fi9u+iEw HNijb5arUW0Gs8PW5XsmfxKnXYgqIW7vevqruwHSLTOoKcnRWi7gmT7Sv /QYkGczvfRbrjE1gApJRx2evkaUNZ2fB7BXlPYiQOZgCPFRbz2xInuEJw lFMRY6jiuUOvjs1mIPgrlgnXPnR1fxQvfKef1H+29xrmOlNTf//7DUQMR A==; X-IronPort-AV: E=McAfee;i="6600,9927,10982"; a="19153187" X-IronPort-AV: E=Sophos;i="6.06,264,1705392000"; d="scan'208";a="19153187" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Feb 2024 09:04:47 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10982"; a="935116809" X-IronPort-AV: E=Sophos;i="6.06,264,1705392000"; d="scan'208";a="935116809" Received: from black.fi.intel.com ([10.237.72.28]) by fmsmga001.fm.intel.com with ESMTP; 12 Feb 2024 09:04:43 -0800 Received: by black.fi.intel.com (Postfix, from userid 1003) id A9268138; Mon, 12 Feb 2024 19:04:42 +0200 (EET) From: Andy Shevchenko To: Andy Shevchenko , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Andy Shevchenko , Geert Uytterhoeven , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Robin van der Gracht , Paul Burton Subject: [PATCH v2 03/15] auxdisplay: linedisp: Use unique number for id Date: Mon, 12 Feb 2024 19:01:36 +0200 Message-ID: <20240212170423.2860895-4-andriy.shevchenko@linux.intel.com> X-Mailer: git-send-email 2.43.0.rc1.1.gbec44491f096 In-Reply-To: <20240212170423.2860895-1-andriy.shevchenko@linux.intel.com> References: <20240212170423.2860895-1-andriy.shevchenko@linux.intel.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The absence of decrementation of linedisp_id is incorrect in two ways, i.e. it may cause: - an ID exhaustion - (and if the above is addressed) a duplicate id number may be allocated next time a device is added Replace above mentioned approach by using IDA framework. Signed-off-by: Andy Shevchenko --- drivers/auxdisplay/line-display.c | 13 ++++++++++--- drivers/auxdisplay/line-display.h | 2 ++ 2 files changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/auxdisplay/line-display.c b/drivers/auxdisplay/line-display.c index 310e9bfb41ae..c4dbb13293d1 100644 --- a/drivers/auxdisplay/line-display.c +++ b/drivers/auxdisplay/line-display.c @@ -11,6 +11,7 @@ #include #include +#include #include #include #include @@ -188,11 +189,14 @@ static struct attribute *linedisp_attrs[] = { }; ATTRIBUTE_GROUPS(linedisp); +static DEFINE_IDA(linedisp_id); + static void linedisp_release(struct device *dev) { struct linedisp *linedisp = container_of(dev, struct linedisp, dev); kfree(linedisp->message); + ida_free(&linedisp_id, linedisp->id); } static const struct device_type linedisp_type = { @@ -214,7 +218,6 @@ int linedisp_register(struct linedisp *linedisp, struct device *parent, unsigned int num_chars, char *buf, void (*update)(struct linedisp *linedisp)) { - static atomic_t linedisp_id = ATOMIC_INIT(-1); int err; memset(linedisp, 0, sizeof(*linedisp)); @@ -225,9 +228,13 @@ int linedisp_register(struct linedisp *linedisp, struct device *parent, linedisp->num_chars = num_chars; linedisp->scroll_rate = DEFAULT_SCROLL_RATE; + err = ida_alloc(&linedisp_id, GFP_KERNEL); + if (err < 0) + return err; + linedisp->id = err; + device_initialize(&linedisp->dev); - dev_set_name(&linedisp->dev, "linedisp.%lu", - (unsigned long)atomic_inc_return(&linedisp_id)); + dev_set_name(&linedisp->dev, "linedisp.%u", linedisp->id); /* initialise a timer for scrolling the message */ timer_setup(&linedisp->timer, linedisp_scroll, 0); diff --git a/drivers/auxdisplay/line-display.h b/drivers/auxdisplay/line-display.h index 0f5891d34c48..1fbe57fdc4cb 100644 --- a/drivers/auxdisplay/line-display.h +++ b/drivers/auxdisplay/line-display.h @@ -14,6 +14,7 @@ /** * struct linedisp - character line display private data structure * @dev: the line display device + * @id: instance id of this display * @timer: timer used to implement scrolling * @update: function called to update the display * @buf: pointer to the buffer for the string currently displayed @@ -25,6 +26,7 @@ */ struct linedisp { struct device dev; + unsigned int id; struct timer_list timer; void (*update)(struct linedisp *linedisp); char *buf; -- 2.43.0.rc1.1.gbec44491f096