[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <dbe47f5d3b9aaef9815d2659df3a5161@codeaurora.org>
Date: Mon, 10 Aug 2020 12:11:04 -0700
From: bbhatt@...eaurora.org
To: Manivannan Sadhasivam <manivannan.sadhasivam@...aro.org>
Cc: linux-arm-msm@...r.kernel.org, hemantk@...eaurora.org,
jhugo@...eaurora.org, linux-kernel@...r.kernel.org,
linux-arm-msm-owner@...r.kernel.org
Subject: Re: [PATCH v6 11/11] bus: mhi: core: Introduce sysfs entries for MHI
On 2020-08-06 22:22, Manivannan Sadhasivam wrote:
> On Mon, Jul 27, 2020 at 07:02:20PM -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@...eaurora.org>
>> ---
>> 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..1d5d0d6
>> --- /dev/null
>> +++ b/Documentation/ABI/stable/sysfs-bus-mhi
>> @@ -0,0 +1,21 @@
>> +What: /sys/bus/mhi/devices/.../serialnumber
>> +Date: Jul 2020
>> +KernelVersion: 5.8
>> +Contact: Bhaumik Bhatt <bbhatt@...eaurora.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.
>
> I think you're not using tabs here and that's why it is showing
> mangled. Please
> use tabs as like other files.
>
> Thanks,
> Mani
>
Hi Mani,
I am using tabs actually. I, in fact, copied another file
(sysfs-bus-vmbus) and only modified the
required entries and did a diff to confirm.
I doubt there is more I can do.
Please let me know if the next patch is acceptable soon.
>> +
>> +What: /sys/bus/mhi/devices/.../oem_pk_hash
>> +Date: Jul 2020
>> +KernelVersion: 5.8
>> +Contact: Bhaumik Bhatt <bbhatt@...eaurora.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@...eaurora.org>
>> L: linux-arm-msm@...r.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
>>
Powered by blists - more mailing lists