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 X-Spam-Level: X-Spam-Status: No, score=-16.4 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF18FC43468 for ; Mon, 21 Sep 2020 13:58:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8214B20866 for ; Mon, 21 Sep 2020 13:58:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="ca/xuhXF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727340AbgIUN6k (ORCPT ); Mon, 21 Sep 2020 09:58:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36596 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726720AbgIUN6k (ORCPT ); Mon, 21 Sep 2020 09:58:40 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4AE39C0613CF for ; Mon, 21 Sep 2020 06:58:40 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id t7so7527443pjd.3 for ; Mon, 21 Sep 2020 06:58:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=9hSV7fSUtzdZKmvu2s5Ab7d0Ct/uxMH78YXRXFCN6qw=; b=ca/xuhXFSfKKMmGzf7dK3R6B2A/KV6Qryv0ZOqBorcAICHIQnyg1bN5NJp3NbUkoxH P6PkelBN0n9ZZzKxnt+VJ3rYjAceKgEogA00BGmFB0xmg+lBVkgYbA8wZi+tM3E9x9Dd za85lf2Dm3DtmQJKT1lPiI8DwQwUZDvQN8lQ4YrkM/MmhI4AsSsfvKMtc7rpktGzbXch wtLIu86rBFkh0StJoNbheg92t/xaR/8ZyJ2SdYOoGaEyHmI/R9ls/n4LtOOKo3+Yd9Xf QTakkzfrPVswO+VS6lrVywLjd/brhdUPOjcUzXjaYDOtEHXGMDSyHo9YFc/r3Of8ETHM ZTNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=9hSV7fSUtzdZKmvu2s5Ab7d0Ct/uxMH78YXRXFCN6qw=; b=RBuyfQUBcqm+1XocqWDmOv5yTWCgy1VgPL/kmk6pKD0RTn4kb3p4OpzThpasFCe+r9 Jxx3qNMhxmVh9E1/mrfGnWl//q8o5KXS+krL2CXKjmOB4G4/CoYDr3luFnf8QTQO61pt nj2OMeQ1CXEFIxJE/j7MFelxkO0bk1YsVIE6Si9pCTshqMc/oifHjrawQgkUU4Q1HW7U 4NILDQEEIgFSsESs58Gj/JvWOkdBjrS8j8qOiLLHPHX0491fL9d6GBkf7ZmxbkBTyCNv JoU2Qwx3Ev98pq2Koe9FKlmXLRyBqtqcKRfsrLdem4BIzlgTtV4HRTX41mU+zrCISQGe AwlQ== X-Gm-Message-State: AOAM5325i5L92hVQ6VDZMRbeiltQcPCKjT5NobKGrBxtExFXIGRLv6do 2lXyd2b/EFSFdA5tVRNZZNeU X-Google-Smtp-Source: ABdhPJyI5KAWB7AqZ+yK56GJpopjzhYgHkWKNeodFVltKLu2c3ADqXqA/qqH0CDo0Er+yrk3Isl3fw== X-Received: by 2002:a17:90a:9317:: with SMTP id p23mr13235pjo.160.1600696719779; Mon, 21 Sep 2020 06:58:39 -0700 (PDT) Received: from Mani-XPS-13-9360 ([2409:4072:6d03:bd12:1004:2ccf:6900:b97]) by smtp.gmail.com with ESMTPSA id m20sm12351965pfa.115.2020.09.21.06.58.35 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Mon, 21 Sep 2020 06:58:38 -0700 (PDT) Date: Mon, 21 Sep 2020 19:28:32 +0530 From: Manivannan Sadhasivam To: Bhaumik Bhatt Cc: linux-arm-msm@vger.kernel.org, hemantk@codeaurora.org, jhugo@codeaurora.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 3/3] bus: mhi: core: Introduce sysfs entries for MHI Message-ID: <20200921135832.GC3262@Mani-XPS-13-9360> References: <1600457992-18448-1-git-send-email-bbhatt@codeaurora.org> <1600457992-18448-4-git-send-email-bbhatt@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1600457992-18448-4-git-send-email-bbhatt@codeaurora.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On Fri, Sep 18, 2020 at 12:39:52PM -0700, Bhaumik Bhatt wrote: > Introduce sysfs entries to enable userspace clients the ability to read > the serial number and the OEM PK Hash values obtained from BHI. OEMs > need to read these device-specific hardware information values through > userspace for factory testing purposes and cannot be exposed via degbufs > as it may remain disabled for performance reasons. Also, update the > documentation for ABI to include these entries. > > Signed-off-by: Bhaumik Bhatt Reviewed-by: Manivannan Sadhasivam Thanks, Mani > --- > Documentation/ABI/stable/sysfs-bus-mhi | 21 ++++++++++++++ > MAINTAINERS | 1 + > drivers/bus/mhi/core/init.c | 53 ++++++++++++++++++++++++++++++++++ > 3 files changed, 75 insertions(+) > create mode 100644 Documentation/ABI/stable/sysfs-bus-mhi > > diff --git a/Documentation/ABI/stable/sysfs-bus-mhi b/Documentation/ABI/stable/sysfs-bus-mhi > new file mode 100644 > index 0000000..ecfe766 > --- /dev/null > +++ b/Documentation/ABI/stable/sysfs-bus-mhi > @@ -0,0 +1,21 @@ > +What: /sys/bus/mhi/devices/.../serialnumber > +Date: Sept 2020 > +KernelVersion: 5.10 > +Contact: Bhaumik Bhatt > +Description: The file holds the serial number of the client device obtained > + using a BHI (Boot Host Interface) register read after at least > + one attempt to power up the device has been done. If read > + without having the device power on at least once, the file will > + read all 0's. > +Users: Any userspace application or clients interested in device info. > + > +What: /sys/bus/mhi/devices/.../oem_pk_hash > +Date: Sept 2020 > +KernelVersion: 5.10 > +Contact: Bhaumik Bhatt > +Description: The file holds the OEM PK Hash value of the endpoint device > + obtained using a BHI (Boot Host Interface) register read after > + at least one attempt to power up the device has been done. If > + read without having the device power on at least once, the file > + will read all 0's. > +Users: Any userspace application or clients interested in device info. > diff --git a/MAINTAINERS b/MAINTAINERS > index deaafb6..11e7be9 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -11323,6 +11323,7 @@ M: Hemant Kumar > L: linux-arm-msm@vger.kernel.org > S: Maintained > T: git git://git.kernel.org/pub/scm/linux/kernel/git/mani/mhi.git > +F: Documentation/ABI/stable/sysfs-bus-mhi > F: Documentation/mhi/ > F: drivers/bus/mhi/ > F: include/linux/mhi.h > diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c > index 61e5885..1b4161e 100644 > --- a/drivers/bus/mhi/core/init.c > +++ b/drivers/bus/mhi/core/init.c > @@ -76,6 +76,56 @@ const char *to_mhi_pm_state_str(enum mhi_pm_state state) > return mhi_pm_state_str[index]; > } > > +static ssize_t serial_number_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct mhi_device *mhi_dev = to_mhi_device(dev); > + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; > + > + return snprintf(buf, PAGE_SIZE, "Serial Number: %u\n", > + mhi_cntrl->serial_number); > +} > +static DEVICE_ATTR_RO(serial_number); > + > +static ssize_t oem_pk_hash_show(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct mhi_device *mhi_dev = to_mhi_device(dev); > + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; > + int i, cnt = 0; > + > + for (i = 0; i < ARRAY_SIZE(mhi_cntrl->oem_pk_hash); i++) > + cnt += snprintf(buf + cnt, PAGE_SIZE - cnt, > + "OEMPKHASH[%d]: 0x%x\n", i, > + mhi_cntrl->oem_pk_hash[i]); > + > + return cnt; > +} > +static DEVICE_ATTR_RO(oem_pk_hash); > + > +static struct attribute *mhi_sysfs_attrs[] = { > + &dev_attr_serial_number.attr, > + &dev_attr_oem_pk_hash.attr, > + NULL, > +}; > + > +static const struct attribute_group mhi_sysfs_group = { > + .attrs = mhi_sysfs_attrs, > +}; > + > +static int mhi_create_sysfs(struct mhi_controller *mhi_cntrl) > +{ > + return sysfs_create_group(&mhi_cntrl->mhi_dev->dev.kobj, > + &mhi_sysfs_group); > +} > + > +static void mhi_destroy_sysfs(struct mhi_controller *mhi_cntrl) > +{ > + sysfs_remove_group(&mhi_cntrl->mhi_dev->dev.kobj, &mhi_sysfs_group); > +} > + > /* MHI protocol requires the transfer ring to be aligned with ring length */ > static int mhi_alloc_aligned_ring(struct mhi_controller *mhi_cntrl, > struct mhi_ring *ring, > @@ -917,6 +967,8 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl, > mhi_cntrl->mhi_dev = mhi_dev; > > mhi_create_debugfs(mhi_cntrl); > + if (mhi_create_sysfs(mhi_cntrl)) > + dev_err(mhi_cntrl->cntrl_dev, "Failed to create sysfs entries\n"); > > return 0; > > @@ -940,6 +992,7 @@ void mhi_unregister_controller(struct mhi_controller *mhi_cntrl) > struct mhi_chan *mhi_chan = mhi_cntrl->mhi_chan; > unsigned int i; > > + mhi_destroy_sysfs(mhi_cntrl); > mhi_destroy_debugfs(mhi_cntrl); > > kfree(mhi_cntrl->mhi_cmd); > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project >