From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 65AB2368284; Sun, 8 Feb 2026 15:44:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=159.226.251.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770565495; cv=none; b=Zc781fup6H9RKLwBNn37I+4puUiR1TFL8ns8ZKWu8pREmDutCYbOfXT10/UnR1cFdD9n+NDhcJYpGLUtMaBPUCh9qfTipH1wCnHIpBxEngy29Qvhwxy6GP/IPW5QzNquYhKThDzpfSJMJIeQf4j2sKv9MYqRFmBtQVN9TlvoqIc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770565495; c=relaxed/simple; bh=z5OJZCmVudQOwiMBl2Zl8cnI9SUvpifHV3ljj91AbcU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=lNTRjiGbDV+xdc7ce73XtWkZZwFbBgPRPJTfC7xUti3Rcm1KpUcsOkCMOis0QOr829DG4ShY0FkJM/x+QddrYUkpS8dQjf/er9QqwzC8sDm5agLpmI9XILjKVXlwEk648cv/p7WdN1ID/An3W+Wu+WFhAirhqz6l3TUhQcIWTx0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=isrc.iscas.ac.cn; spf=pass smtp.mailfrom=isrc.iscas.ac.cn; arc=none smtp.client-ip=159.226.251.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=isrc.iscas.ac.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=isrc.iscas.ac.cn Received: from duge-virtual-machine (unknown [223.66.170.192]) by APP-05 (Coremail) with SMTP id zQCowAAnvA9jr4hp9bvOBw--.26116S2; Sun, 08 Feb 2026 23:44:37 +0800 (CST) Date: Sun, 8 Feb 2026 23:44:35 +0800 From: Jiayu Du To: Krzysztof Kozlowski , ulf.hansson@linaro.org, adrian.hunter@intel.com, robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org Cc: pjw@kernel.org, palmer@dabbelt.com, aou@eecs.berkeley.edu, linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, gaohan@iscas.ac.cn, me@ziyao.cc Subject: Re: [PATCH 2/3] mmc: sdhci-dwcmshc: Add Canaan K230 DWCMSHC controller support Message-ID: References: <20260204082908.27501-1-jiayu.riscv@isrc.iscas.ac.cn> <20260204082908.27501-3-jiayu.riscv@isrc.iscas.ac.cn> Precedence: bulk X-Mailing-List: linux-mmc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-CM-TRANSID:zQCowAAnvA9jr4hp9bvOBw--.26116S2 X-Coremail-Antispam: 1UD129KBjvJXoWxWw1xuF4fWFWrWr4fKw1ftFb_yoW5Ar17pr W8JFWUKr48JF1Ygw1vgw18GasIyw1DGFW3Xr1fG34UWw1qyr17Gr40gr1Y9as5uF13AF1Y vayUtr9xCFsxJrJanT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUvvb7Iv0xC_Kw4lb4IE77IF4wAFF20E14v26r4j6ryUM7CY07I2 0VC2zVCF04k26cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28lY4IEw2IIxxk0rw A2F7IY1VAKz4vEj48ve4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Jr0_JF4l84ACjcxK6xII jxv20xvEc7CjxVAFwI0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVWUJVW8JwA2z4x0Y4vEx4 A2jsIEc7CjxVAFwI0_Gr0_Gr1UM2AIxVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI 64kE6c02F40Ex7xfMcIj6xIIjxv20xvE14v26r1j6r18McIj6I8E87Iv67AKxVWUJVW8Jw Am72CE4IkC6x0Yz7v_Jr0_Gr1lF7xvr2IY64vIr41lFIxGxcIEc7CjxVA2Y2ka0xkIwI1l c7CjxVAaw2AFwI0_Jw0_GFyl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr 1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE 14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7 IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E 87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73Uj IFyTuYvjxUqiFxDUUUU X-CM-SenderInfo: 5mld534oul2uny6l223fol2u1dvotugofq/ On Sat, Feb 07, 2026 at 10:32:55AM +0100, Krzysztof Kozlowski wrote: > On 07/02/2026 09:45, Jiayu Du wrote: > > On Fri, Feb 06, 2026 at 02:26:40PM +0100, Krzysztof Kozlowski wrote: > >> On 04/02/2026 09:29, Jiayu Du wrote: > >>> +static int dwcmshc_k230_init(struct device *dev, struct sdhci_host *host, > >>> + struct dwcmshc_priv *dwc_priv) > >>> +{ > >>> + static const char * const clk_ids[] = {"base", "timer", "ahb"}; > >>> + struct device_node *usb_phy_node; > >>> + struct k230_priv *k230_priv; > >>> + u32 data; > >>> + int ret; > >>> + > >>> + k230_priv = devm_kzalloc(dev, sizeof(struct k230_priv), GFP_KERNEL); > >>> + if (!k230_priv) > >>> + return -ENOMEM; > >>> + dwc_priv->priv = k230_priv; > >>> + > >>> + usb_phy_node = of_find_compatible_node(NULL, NULL, "canaan,k230-usb-phy"); > >> > >> Hm? You should use phandles, not look for various nodes. > > > > Only one usbphy node has the canaan, k230-usb-phy compatibility. > > So in this situation, is it ok to continue using of_find_compatible_node? > > Amount of nodes does not matter. This is not how you express > links/dependencies between devices. Phandle is for this. This is wrong > on many levels, including missing device links, bypassing kernel API/layers. Thank you for your review. I will fix it. > > > > > >>> + if (!usb_phy_node) { > >> > >> Please follow Linux coding style. > > > > I will fix it in next version. > > > >>> + return dev_err_probe(dev, -ENODEV, > >>> + "Failed to find k230-usb-phy node\n"); > >>> + } > >>> + > >>> + k230_priv->hi_sys_regmap = device_node_to_regmap(usb_phy_node); > >>> + of_node_put(usb_phy_node); > >>> + if (IS_ERR(k230_priv->hi_sys_regmap)) { > >>> + return dev_err_probe(dev, PTR_ERR(k230_priv->hi_sys_regmap), > >>> + "Failed to get k230-usb-phy regmap\n"); > >>> + } > >>> + > >>> + ret = dwcmshc_get_enable_other_clks(mmc_dev(host->mmc), dwc_priv, > >>> + ARRAY_SIZE(clk_ids), clk_ids); > >>> + if (ret) { > >>> + return dev_err_probe(dev, ret, > >>> + "Failed to get/enable k230 mmc other clocks\n"); > >>> + } > >>> + > >>> + if (of_device_is_compatible(dev->of_node, "canaan,k230-sdio")) { > >> > >> Driver match data is for this. > > > > What you mean is that I shouldn't use of_find_compatible_node, but I can > > use device_get_match_data instead? Then I can continue to distinguish > > between SDIO and eMMC to do parameter configuration > > > > Or do you mean that I should put the parameters to be adjusted into the > > pdata structure? But currently, the dwcmshc structure is not suitable for > > containing vendor-specific properties. > > Parameters should go to driver match data. I already requested this for > some other driver and this has to be fixed. I will make fix to enable dwcmshc_pltfm_data to support the addition of vendor-specific properties. And if possible, could you give me with some examples? I would be very grateful. > > Best regards, > Krzysztof