From: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
To: Bhaumik Bhatt <bbhatt@codeaurora.org>
Cc: linux-arm-msm@vger.kernel.org, hemantk@codeaurora.org,
jhugo@codeaurora.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 11/11] bus: mhi: core: Introduce sysfs entries for MHI
Date: Tue, 11 Aug 2020 11:48:58 +0530 [thread overview]
Message-ID: <20200811061858.GB2762@Mani-XPS-13-9360> (raw)
In-Reply-To: <1597096865-19636-12-git-send-email-bbhatt@codeaurora.org>
On Mon, Aug 10, 2020 at 03:01:05PM -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 <bbhatt@codeaurora.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
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..59da56d
> --- /dev/null
> +++ b/Documentation/ABI/stable/sysfs-bus-mhi
> @@ -0,0 +1,21 @@
> +What: /sys/bus/mhi/devices/.../serialnumber
> +Date: Aug 2020
> +KernelVersion: 5.10
> +Contact: Bhaumik Bhatt <bbhatt@codeaurora.org>
> +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: Aug 2020
> +KernelVersion: 5.10
> +Contact: Bhaumik Bhatt <bbhatt@codeaurora.org>
> +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 e64e5db..5e49316 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -11018,6 +11018,7 @@ M: Hemant Kumar <hemantk@codeaurora.org>
> 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 972dbf0..c086ef2 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
>
next prev parent reply other threads:[~2020-08-11 6:19 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-10 22:00 [PATCH v7 00/11] Introduce features and debugfs/sysfs entries for MHI Bhaumik Bhatt
2020-08-10 22:00 ` [PATCH v7 01/11] bus: mhi: core: Remove double occurrence for mhi_ctrl_ev_task() declaration Bhaumik Bhatt
2020-08-10 22:00 ` [PATCH v7 02/11] bus: mhi: core: Abort suspends due to outgoing pending packets Bhaumik Bhatt
2020-08-10 22:00 ` [PATCH v7 03/11] bus: mhi: core: Use helper API to trigger a non-blocking host resume Bhaumik Bhatt
2020-08-10 22:00 ` [PATCH v7 04/11] bus: mhi: core: Trigger host resume if suspended during mhi_device_get() Bhaumik Bhatt
2020-08-10 22:00 ` [PATCH v7 05/11] bus: mhi: core: Use generic name field for an MHI device Bhaumik Bhatt
2020-08-10 22:01 ` [PATCH v7 06/11] bus: mhi: core: Introduce helper function to check device state Bhaumik Bhatt
2020-08-10 22:01 ` [PATCH v7 07/11] bus: mhi: core: Introduce counters to track MHI device state transitions Bhaumik Bhatt
2020-08-10 22:01 ` [PATCH v7 08/11] bus: mhi: core: Introduce debugfs entries for MHI Bhaumik Bhatt
2020-08-11 0:30 ` kernel test robot
2020-08-11 6:24 ` Manivannan Sadhasivam
2020-08-10 22:01 ` [PATCH v7 09/11] bus: mhi: core: Read and save device hardware information from BHI Bhaumik Bhatt
2020-08-10 22:01 ` [PATCH v7 10/11] bus: mhi: core: Introduce APIs to allocate and free the MHI controller Bhaumik Bhatt
2020-08-10 22:01 ` [PATCH v7 11/11] bus: mhi: core: Introduce sysfs entries for MHI Bhaumik Bhatt
2020-08-11 6:18 ` Manivannan Sadhasivam [this message]
2020-08-11 6:26 ` [PATCH v7 00/11] Introduce features and debugfs/sysfs " Manivannan Sadhasivam
2020-08-11 17:53 ` bbhatt
2020-08-18 9:52 ` Manivannan Sadhasivam
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