From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 08E0F65E for ; Wed, 11 Oct 2023 09:26:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="vecbr0Wi" Received: from mail-wm1-x332.google.com (mail-wm1-x332.google.com [IPv6:2a00:1450:4864:20::332]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D299D91 for ; Wed, 11 Oct 2023 02:26:46 -0700 (PDT) Received: by mail-wm1-x332.google.com with SMTP id 5b1f17b1804b1-406618d080eso63194395e9.2 for ; Wed, 11 Oct 2023 02:26:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1697016405; x=1697621205; darn=vger.kernel.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=3BUBCHAP73g+38QvM7dHiUG8I9QRyAUU3cBnzO6ITqY=; b=vecbr0WiqQjT5m1He5rozYK78PzNPPeH9wweaN/0aueVRFLQt8jQ7tYgiePtw18XT2 UUFDDMTXdaOooReXkklZMF7NGpIn0mPJARYvX/bdwKXi+yD+1qdHpJ30kkE7DJpTfdKi qwMDXjy9yf03fbpiR7jNP89fqsqzt0nstEWhYoJPE48Y66RfqJ46Y0m4aT+rBD87Wp0n ECtO182xxMRDD/O8WSjzuL/aUdrQGCggToRQSccSNiGrgOwrDMX/C+Wy8RomyWptRNnM rg0ZRhhxIDkcXqcVxPQqKPLWWRsWDWYrtTcYoiVe2K1bY8a1a2ExU+TiGWKPuX9WVnR3 BGdA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697016405; x=1697621205; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=3BUBCHAP73g+38QvM7dHiUG8I9QRyAUU3cBnzO6ITqY=; b=L3YEb0PknvmjePUI3QwXZbd2TVwqMsTP90xQb7r/MlTpBhkk0JTwdAfAG48/KAt96G a+uUD25h9aBBtXQGvI4vBiOxQmwQiOGwacXSlVrXhrxsWCw2ODxHd+NpdVKnDTqYaPl8 cG/X/2/BDLU51AP8nTCNNT8Pb7tnosimH7PtRDY6WvvIwYRe0BAVh2BwCNRyv6aTjTSu 0D6/zL0AnGd0nLGUFKPuxKbiBYY+J6N+s0Apevknt6cvQNiQcN3V3NOOFoBaEplv5Jru hn8GVTmfCnh1z4cLIVsArLsvrUbmuxZvUPouPwxJer/WQ8X/S8XRdlesf3cqfaf9p6/j gArQ== X-Gm-Message-State: AOJu0YyRYbgHdCXKQSAf+pOGSBkDnz1OOUan/WrwvmmHEFjJpMEmQx9K rQZTqcCWfbeGHN3C4Ackf1oQqw== X-Google-Smtp-Source: AGHT+IEmstm4YZMcFtZGfJcKYWGQ0iTcj4Ct9t9kUcPLrpuam0kNIWDwV4+jgBsuR8kgZEkR/FNqfQ== X-Received: by 2002:a1c:4c01:0:b0:407:5185:1923 with SMTP id z1-20020a1c4c01000000b0040751851923mr5235189wmf.4.1697016405127; Wed, 11 Oct 2023 02:26:45 -0700 (PDT) Received: from [192.168.86.24] ([5.133.47.210]) by smtp.googlemail.com with ESMTPSA id bd5-20020a05600c1f0500b004030e8ff964sm18753144wmb.34.2023.10.11.02.26.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 11 Oct 2023 02:26:43 -0700 (PDT) Message-ID: <490c6740-06cb-9ee6-ca8c-3ab404109344@linaro.org> Date: Wed, 11 Oct 2023 10:26:43 +0100 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCH v12 7/7] nvmem: core: Expose cells through sysfs Content-Language: en-US To: Miquel Raynal Cc: Greg Kroah-Hartman , Michael Walle , =?UTF-8?B?UmFmYcWCIE1pxYJlY2tp?= , Rob Herring , Frank Rowand , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Robert Marko , Thomas Petazzoni , Luka Perkov , Randy Dunlap , Chen-Yu Tsai , Daniel Golle References: <20231005155907.2701706-1-miquel.raynal@bootlin.com> <20231005155907.2701706-8-miquel.raynal@bootlin.com> <318fe799-f53e-64ed-b631-d099bb5202f4@linaro.org> <20231011091524.0c9ecc55@xps-13> <548849a8-9f11-5274-778e-f291267603bb@linaro.org> <20231011103306.08f1fbd4@xps-13> <20231011105829.778bed58@xps-13> From: Srinivas Kandagatla In-Reply-To: <20231011105829.778bed58@xps-13> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,RCVD_IN_DNSWL_NONE, RCVD_IN_SBL_CSS,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net On 11/10/2023 09:58, Miquel Raynal wrote: > Hi Srinivas, > > srinivas.kandagatla@linaro.org wrote on Wed, 11 Oct 2023 09:45:11 +0100: > >> On 11/10/2023 09:33, Miquel Raynal wrote: >>> Hi Srinivas, >>> >>> srinivas.kandagatla@linaro.org wrote on Wed, 11 Oct 2023 09:27:20 +0100: >>> >>>> On 11/10/2023 08:15, Miquel Raynal wrote: >>>>>>> + >>>>>>> + nvmem_cells_group.bin_attrs = cells_attrs; >>>>>>> + >>>>>>> + ret = devm_device_add_groups(&nvmem->dev, nvmem_cells_groups); >>>>>>> + if (ret) >>>>>>> + goto unlock_mutex; >>>>>> This is going to create groups after the nvmem device is added, isn't this going to be problem with user space notifications? >>>>> Greg said it was not. I hope I understood correctly 😄 >>>>> >>>>> And anyway, cells have never been available to userspace, so there is >>>>> nothing userspace might expect yet? >>>> I agree, but once we add sysfs uapi then this is going to change. >>> >>> Can you elaborate? I'm not sure I follow you here. Is there still a >>> problem you fear or you think it's okay? >>> >> Now that we add cells to sysfs. >> AFAIU, By the time the userspace sees the udev event from this device we might not have cells populated. > > Yes, but why would this be a problem? > It will be problem if the userspace is using things like libudev to act on these events. There seems to be some caching of attributes in udev during event more info http://www.kroah.com/log/blog/2013/06/26/how-to-create-a-sysfs-file-correctly/ --srini > Thanks, > Miquèl