Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932172AbbFDUxV (ORCPT ); Thu, 4 Jun 2015 16:53:21 -0400 Received: from smtp.codeaurora.org ([198.145.29.96]:58480 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753136AbbFDUxR (ORCPT ); Thu, 4 Jun 2015 16:53:17 -0400 Message-ID: <763dbc7b708b5d5b18ce0b5adcc41016.squirrel@www.codeaurora.org> In-Reply-To: References: <1433324255-27510-1-git-send-email-ygardi@codeaurora.org> <1433324255-27510-5-git-send-email-ygardi@codeaurora.org> Date: Thu, 4 Jun 2015 20:53:16 -0000 Subject: Re: [PATCH v2 4/4] scsi: ufs: probe and init of variant driver from the platform device From: ygardi@codeaurora.org To: "Akinobu Mita" , merez@qti.qualcomm.com, dovl@qti.qualcomm.com Cc: "Yaniv Gardi" , "Jej B" , "LKML" , "linux-scsi@vger.kernel.org" , linux-arm-msm@vger.kernel.org, "Santosh Y" , linux-scsi-owner@vger.kernel.org, "Subhash Jadavani" , "Paul Bolle" , "Gilad Broner" , "Rob Herring" , "Pawel Moll" , "Mark Rutland" , "Ian Campbell" , "Kumar Gala" , "Vinayak Holikatti" , "James E.J. Bottomley" , "Dolev Raviv" , "Christoph Hellwig" , "Sujit Reddy Thumma" , "Raviv Shvili" , "Sahitya Tummala" , "open list:OPEN FIRMWARE AND..." User-Agent: SquirrelMail/1.4.22-4.el6 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT X-Priority: 3 (Normal) Importance: Normal Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2637 Lines: 76 > Hi Yaniv, > > 2015-06-03 18:37 GMT+09:00 Yaniv Gardi : >> @@ -321,7 +313,22 @@ static int ufshcd_pltfrm_probe(struct >> platform_device *pdev) >> goto out; >> } >> >> - hba->vops = get_variant_ops(&pdev->dev); >> + err = of_platform_populate(node, NULL, NULL, &pdev->dev); >> + if (err) >> + dev_err(&pdev->dev, >> + "%s: of_platform_populate() failed\n", >> __func__); >> + >> + ufs_variant_node = of_get_next_available_child(node, NULL); >> + >> + if (!ufs_variant_node) { >> + dev_dbg(&pdev->dev, "failed to find ufs_variant_node >> child\n"); >> + } else { >> + ufs_variant_pdev = >> of_find_device_by_node(ufs_variant_node); >> + >> + if (ufs_variant_pdev) >> + hba->vops = (struct ufs_hba_variant_ops *) >> + dev_get_drvdata(&ufs_variant_pdev->dev); >> + } > > I have no strong objection to 'ufs_variant' sub-node. But why can't we > simply add an of_device_id to ufs_of_match, like below: > > static const struct of_device_id ufs_of_match[] = { > { .compatible = "jedec,ufs-1.1"}, > #if IS_ENABLED(SCSI_UFS_QCOM) > { .compatible = "qcom,ufs", .data = &ufs_hba_qcom_vops }, > #neidf > {}, > }; > > and get hba->vops by get_variant_ops()? > Hi Mita, thanks for your comments. The whole idea, of having a sub-node which includes all variant specific attributes is to separate the UFS Platform device component, from the need to know "qcom" or any other future variant. I believe it keeps the code more modular, and clean - meaning - no #ifdef's and no need to include all variant attributes inside the driver DT node. in that case, we simply have a DT node that is compatible to the Jdec standard, and sub-node to include variant info. I hope you agree with this new design, since it provides a good answer to every future variant that will be added, without the need to change the platform file. thanks for your time, Mita please share your thoughts. > There is something similar in > drivers/net/ethernet/freescale/fsl_pq_mdio.c > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/