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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9ADC5C43334 for ; Wed, 13 Jul 2022 14:25:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229497AbiGMOZv (ORCPT ); Wed, 13 Jul 2022 10:25:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59646 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235360AbiGMOZo (ORCPT ); Wed, 13 Jul 2022 10:25:44 -0400 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D758C3337F for ; Wed, 13 Jul 2022 07:25:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1657722342; x=1689258342; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ge8z9tQugUy9cTnjB8duw2RGaf7wv9bBNLATuLcW9CY=; b=iz6MTCD55FLihvOBywSMsuFeJlIu7ceI3+WaoNQaUA7KMNFo8E0KZkN0 ptIOMZAYcRsV77kzQOF7A/wd8Bpdm6UkBP0vAhVbSiv+L9+ZEw8ugNdPb nRPNmGW8lb3uWyJqik7+0NK6x5fXcPFiNvnanEt+z5Z073tDmT/84FF6K uIgx7h8D4LnClJrKxgv6NL4r98l8ZCB0BvBIExRjPcQpWEeze2Ex+bmW7 9DuR3GDORdLvHAjvy/cdhcqYXJl3XC9rmSpdvxSa12vySAYuymoLGxX8H lX6+8RCvOkbEXHf8+6t6Ml1hBq+6xxRd1mC5xLfdxwVwiSXANN3eeqQOQ Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10407"; a="285968195" X-IronPort-AV: E=Sophos;i="5.92,267,1650956400"; d="scan'208";a="285968195" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jul 2022 07:25:42 -0700 X-IronPort-AV: E=Sophos;i="5.92,267,1650956400"; d="scan'208";a="570643756" Received: from bard-ubuntu.sh.intel.com ([10.239.185.57]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Jul 2022 07:25:40 -0700 From: Bard Liao To: alsa-devel@alsa-project.org, vkoul@kernel.org Cc: vinod.koul@linaro.org, linux-kernel@vger.kernel.org, pierre-louis.bossart@linux.intel.com, bard.liao@intel.com Subject: [PATCH 2/3] soundwire: bus: allow device number to be unique at system level Date: Wed, 13 Jul 2022 22:25:28 +0800 Message-Id: <20220713142529.17323-3-yung-chuan.liao@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220713142529.17323-1-yung-chuan.liao@linux.intel.com> References: <20220713142529.17323-1-yung-chuan.liao@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Pierre-Louis Bossart The SoundWire specification allows the device number to be allocated at will. When a system includes multiple SoundWire links, the device number scope is limited to the link to which the device is attached. However, for integration/debug it can be convenient to have a unique device number across the system. This patch adds a 'dev_num_ida_min' field at the bus level, which when set will be used to allocate an IDA. The allocation happens when a hardware device reports as ATTACHED. If any error happens during the enumeration, the allocated IDA is not freed - the device number will be reused if/when the device re-joins the bus. The IDA is only freed when the Linux device is unregistered. Signed-off-by: Pierre-Louis Bossart Reviewed-by: Ranjani Sridharan Reviewed-by: Rander Wang Signed-off-by: Bard Liao --- drivers/soundwire/bus.c | 23 +++++++++++++++++------ include/linux/soundwire/sdw.h | 4 ++++ 2 files changed, 21 insertions(+), 6 deletions(-) diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index 37638c20c804..8970f8560766 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -12,6 +12,7 @@ #include "sysfs_local.h" static DEFINE_IDA(sdw_bus_ida); +static DEFINE_IDA(sdw_peripheral_ida); static int sdw_get_id(struct sdw_bus *bus) { @@ -157,9 +158,11 @@ static int sdw_delete_slave(struct device *dev, void *data) mutex_lock(&bus->bus_lock); - if (slave->dev_num) /* clear dev_num if assigned */ + if (slave->dev_num) { /* clear dev_num if assigned */ clear_bit(slave->dev_num, bus->assigned); - + if (bus->dev_num_ida_min) + ida_free(&sdw_peripheral_ida, slave->dev_num); + } list_del_init(&slave->node); mutex_unlock(&bus->bus_lock); @@ -639,10 +642,18 @@ static int sdw_get_device_num(struct sdw_slave *slave) { int bit; - bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES); - if (bit == SDW_MAX_DEVICES) { - bit = -ENODEV; - goto err; + if (slave->bus->dev_num_ida_min) { + bit = ida_alloc_range(&sdw_peripheral_ida, + slave->bus->dev_num_ida_min, SDW_MAX_DEVICES, + GFP_KERNEL); + if (bit < 0) + goto err; + } else { + bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES); + if (bit == SDW_MAX_DEVICES) { + bit = -ENODEV; + goto err; + } } /* diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 39058c841469..a2b31d25ea27 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -889,6 +889,9 @@ struct sdw_master_ops { * meaningful if multi_link is set. If set to 1, hardware-based * synchronization will be used even if a stream only uses a single * SoundWire segment. + * @dev_num_ida_min: if set, defines the minimum values for the IDA + * used to allocate system-unique device numbers. This value needs to be + * identical across all SoundWire bus in the system. */ struct sdw_bus { struct device *dev; @@ -913,6 +916,7 @@ struct sdw_bus { u32 bank_switch_timeout; bool multi_link; int hw_sync_min_links; + int dev_num_ida_min; }; int sdw_bus_master_add(struct sdw_bus *bus, struct device *parent, -- 2.25.1