From patchwork Fri Sep 18 19:26:53 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bhaumik Bhatt X-Patchwork-Id: 11785869 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A1835139A for ; Fri, 18 Sep 2020 19:27:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8098022208 for ; Fri, 18 Sep 2020 19:27:13 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="Ty3Yk9xU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726290AbgIRT1H (ORCPT ); Fri, 18 Sep 2020 15:27:07 -0400 Received: from so254-54.mailgun.net ([198.61.254.54]:51937 "EHLO so254-54.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726156AbgIRT1E (ORCPT ); Fri, 18 Sep 2020 15:27:04 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1600457223; h=References: In-Reply-To: Message-Id: Date: Subject: Cc: To: From: Sender; bh=3x6/gUsaoAPlKN8qn8squjxl5ZY1fIQoL/KKDok0n3k=; b=Ty3Yk9xU9Caqys7hDtGL4WoSyvOSEJVImVv0WpQ+LEBZ7+jSQx5doGz0qGseBXqC1EqaH/nH ntAZtgPNapfUZLOm0THaBvVY59fNLNSCYMoV56DxxdGcdRUhkXBmbdQ04uCCyw+5Ovz2RXEb cTojE74wN7yzufg36Yt3sGfX5xQ= X-Mailgun-Sending-Ip: 198.61.254.54 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n06.prod.us-west-2.postgun.com with SMTP id 5f650a074ab73023a75cef5e (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 18 Sep 2020 19:27:03 GMT Sender: bbhatt=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 314CDC43385; Fri, 18 Sep 2020 19:27:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=ALL_TRUSTED,BAYES_00,SPF_FAIL, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from malabar-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: bbhatt) by smtp.codeaurora.org (Postfix) with ESMTPSA id 24C23C433CA; Fri, 18 Sep 2020 19:27:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 24C23C433CA Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=bbhatt@codeaurora.org From: Bhaumik Bhatt To: manivannan.sadhasivam@linaro.org Cc: linux-arm-msm@vger.kernel.org, hemantk@codeaurora.org, jhugo@codeaurora.org, linux-kernel@vger.kernel.org, Bhaumik Bhatt Subject: [PATCH v2 3/3] bus: mhi: core: Introduce sysfs entries for MHI Date: Fri, 18 Sep 2020 12:26:53 -0700 Message-Id: <1600457213-11587-4-git-send-email-bbhatt@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600457213-11587-1-git-send-email-bbhatt@codeaurora.org> References: <1600457213-11587-1-git-send-email-bbhatt@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org 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 --- 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);