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 B0EF2C7619A for ; Wed, 5 Apr 2023 11:35:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237432AbjDELfn (ORCPT ); Wed, 5 Apr 2023 07:35:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46948 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231887AbjDELfl (ORCPT ); Wed, 5 Apr 2023 07:35:41 -0400 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C7C651BD7 for ; Wed, 5 Apr 2023 04:35:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1680694540; x=1712230540; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=z4M+lGF3PxW5jIEFmkFI2Pz3GGvuMaU0PB9nsRWm/Lw=; b=Hwcs9KWlyi8Y93C/nzd+FGEtcdQeEevE3hRgWNanU/7O7h/iJbDS1KnT XbBpFb9k+u26nvsb2atOAoqht9L3RW7VlEsXIEiEqlZT3QIoh06V5HZ5s sQwwzMamvkVekCUfFlSHLR6KC5CKCtch1JFf5Y7Bjh7rUGPGbVvZBHAtH hkfuOdtRbugcej2XKKTL7RayOKoCfqFstkfSQuwfwr/fGdwNf0xKDYGDo CRjlZVaSUrgLHBORYoHHgUzPhOcFf5vZyRXj3jB3ahHmMLK0E55ITrYRr nHDVEjiF/jaEFFpclDiQ1sSSmm2/wa38AJVwBXuvSaUyxgyH8UppyWn+L A==; X-IronPort-AV: E=McAfee;i="6600,9927,10670"; a="370257021" X-IronPort-AV: E=Sophos;i="5.98,319,1673942400"; d="scan'208";a="370257021" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Apr 2023 04:35:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10670"; a="860943315" X-IronPort-AV: E=Sophos;i="5.98,319,1673942400"; d="scan'208";a="860943315" Received: from aslawinx-mobl.ger.corp.intel.com (HELO [10.99.16.144]) ([10.99.16.144]) by orsmga005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Apr 2023 04:35:36 -0700 Message-ID: <030c2cbf-dec3-91fb-ac82-949cf5764b78@linux.intel.com> Date: Wed, 5 Apr 2023 13:35:34 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.9.1 Subject: Re: [EXTERNAL] Re: [PATCH v10] ASoC: tas2781: Add tas2781 driver Content-Language: en-US To: "Ding, Shenghao" , Christophe JAILLET Cc: "Lu, Kevin" , "alsa-devel@alsa-project.org" , "linux-kernel@vger.kernel.org" , "Xu, Baojun" , "Gupta, Peeyush" , "Navada Kanyana, Mukund" , Shenghao Ding <13916275206@139.com>, "broonie@kernel.org" , "lgirdwood@gmail.com" , "perex@perex.cz" , "pierre-louis.bossart@linux.intel.com" References: <20230329100107.8181-1-13916275206@139.com> <8d0d0478-1e45-ea52-f1b7-910b747d6282@linux.intel.com> <7a0cfa60e2a244168edd49c3d2f6a2bd@ti.com> <458d7c2f-bcee-9ec3-e955-9661a06a3349@wanadoo.fr> From: =?UTF-8?Q?Amadeusz_S=c5=82awi=c5=84ski?= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/5/2023 1:21 PM, Ding, Shenghao wrote: > Hi Both > I wrote a test code to verify the be32_to_cpu & be32_to_cpup, > static int __init lkm_init(void) > { > char test_buf[]={0x12, 0x34, 0xab, 0xbc, 0x56, 0x78, 0xef}; > unsigned int *k, p, q; > int i; > > printk("Hello, Shanghai!\n"); > > for (i = 0; i < 4; i ++) { > k = (unsigned int *)&test_buf[i]; > p = be32_to_cpup((__be32 *)k); > q = be32_to_cpu(test_buf[i]); > printk("%d: *k = 0x%08x p = 0x%08x q = 0x%08x %ld\n", > i, *k, p, q, sizeof(unsigned int)); > } > return 0; > } > The output is: > [ 9109.722548] Hello, Shanghai! > [ 9109.726287] 0: *k = 0xbcab3412 p = 0x1234abbc q = 0x12000000 4 > [ 9109.727665] 1: *k = 0x56bcab34 p = 0x34abbc56 q = 0x34000000 4 > [ 9109.728553] 2: *k = 0x7856bcab p = 0xabbc5678 q = 0xabffffff 4 > [ 9109.729308] 3: *k = 0xef7856bc p = 0xbc5678ef q = 0xbcffffff 4 > Apparently, be32_to_cpup's output is what I expected. > Looking forward to your comments. Thanks. > It makes sense, as array access reads 8 bit value, you would need to access value using pointer instead. So instead of doing be32_to_cpu(test_buf[i]) you would need to do be32_to_cpu(*(test_buf + i)) if I didn't mess the pointer magic ;) And then I'm not sure which is better, be32_to_cpup or be32_to_cpu. > BR > Shenghao Ding > -----Original Message----- > From: Christophe JAILLET > Sent: Saturday, April 1, 2023 4:41 AM > To: Ding, Shenghao ; Amadeusz Slawinski ; Shenghao Ding <13916275206@139.com>; broonie@kernel.org; lgirdwood@gmail.com; perex@perex.cz; pierre-louis.bossart@linux.intel.com > Cc: Lu, Kevin ; alsa-devel@alsa-project.org; linux-kernel@vger.kernel.org; Xu, Baojun ; Gupta, Peeyush ; Navada Kanyana, Mukund > Subject: [EXTERNAL] Re: [PATCH v10] ASoC: tas2781: Add tas2781 driver > > Le 31/03/2023 à 04:19, Ding, Shenghao a écrit : >> Hi Amadeusz Sławiński >> Thanks for your comment. >> Answer inline. >> >> -----Original Message----- >> From: Amadeusz Sławiński >> Sent: Thursday, March 30, 2023 7:54 PM >> To: Shenghao Ding <13916275206@139.com>; broonie@kernel.org; >> lgirdwood@gmail.com; perex@perex.cz; >> pierre-louis.bossart@linux.intel.com >> Cc: Lu, Kevin ; Ding, Shenghao >> ; alsa-devel@alsa-project.org; >> linux-kernel@vger.kernel.org; Xu, Baojun ; Gupta, >> Peeyush ; Navada Kanyana, Mukund >> Subject: [EXTERNAL] Re: [PATCH v10] ASoC: tas2781: Add tas2781 driver >> >> On 3/29/2023 12:01 PM, Shenghao Ding wrote: >>> Create tas2781 driver. >>> >>> Signed-off-by: Shenghao Ding <13916275206@139.com> >>> >>> --- >>> Changes in v10: >>> - using be16_to_cpu and be32_to_cpu instead of SMS_HTONS and SMS_HTONL >>> - optimize and reduce the boundary checks >>> - Add comments on some kmemdup instead of kzalloc+memcpy >>> Changes to be committed: >>> modified: sound/soc/codecs/Kconfig >>> modified: sound/soc/codecs/Makefile >>> new file: sound/soc/codecs/tas2781-dsp.c >>> new file: sound/soc/codecs/tas2781-dsp.h >>> new file: sound/soc/codecs/tas2781-i2c.c >>> new file: sound/soc/codecs/tas2781.h >>> --- >> >> ... >> >>> + >>> +static int fw_parse_block_data_kernel(struct tasdevice_fw *tas_fmw, >>> + struct tasdev_blk *block, const struct firmware *fmw, int offset) { >>> + const unsigned char *data = fmw->data; >>> + >>> + if (offset + 16 > fmw->size) { >>> + dev_err(tas_fmw->dev, "%s: File Size error\n", __func__); >>> + offset = -EINVAL; >>> + goto out; >>> + } >>> + block->type = be32_to_cpup((__be32 *)&data[offset]); >> >> Wouldn't just be32_to_cpu(data[offset]) work instead of be32_to_cpup? >> Same in other cases. >> [DING] data[] is a char array, the code will convert data[offset], >> data[offset + 1], data[offset + 2] and data[offset + 3] into host instead of data[offset] only. >> > > Not sure to follow you. > Isn't it the purpose of be32_to_cpu() to take a 32 bits word, in other words 4 x 8 bits char, and swap what if needed (little endian arch)? > > It ends to __swab32() ([1] for the "constant" implementation) > > > be32_to_cpup(&p) ends to __swab32(*p), which really looks to the same as be32_to_cpu(p). > > Can you elaborate more? > > CJ > > > [1]: > https://elixir.bootlin.com/linux/v6.3-rc3/source/include/uapi/linux/swab.h#L18 >