| Message ID | 1593448782-8385-1-git-send-email-bbhatt@codeaurora.org |
|---|---|
| Headers | show |
| Series | Introduce features and debugfs/sysfs entries for MHI | expand |
On Mon, Jun 29, 2020 at 09:39:42AM -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> > --- > Documentation/ABI/stable/sysfs-bus-mhi | 25 ++++++++++++++++ > MAINTAINERS | 1 + > drivers/bus/mhi/core/init.c | 53 ++++++++++++++++++++++++++++++++++ > 3 files changed, 79 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..65ef711 > --- /dev/null > +++ b/Documentation/ABI/stable/sysfs-bus-mhi > @@ -0,0 +1,25 @@ > +What: /sys/bus/mhi/devices/.../serialnumber > +Date: May 2020 July? > +KernelVersion: 5.8 > +Contact: Bhaumik Bhatt <bbhatt@codeaurora.org> > +Description: > + The file holds the serial number of the endpoint device obtained Don't use the term endpoint here. Just say MHI client device. > + 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 the device > + hardware information. > + > +What: /sys/bus/mhi/devices/.../oem_pk_hash > +Date: May 2020 > +KernelVersion: 5.8 > +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 the device > + hardware information. > 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 d2c0f6e..745e146 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); Space after ':' > +} > +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]); Same here. Thanks, Mani > + > + 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 >
Introduce independent bus and device voting mechanism for clients and save hardware information from BHI. Allow reading and modifying some MHI variables for debug, test, and informational purposes using debugfs. Read values for device specific hardware information to be used by OEMs in factory testing such as serial number and PK hash using sysfs. This set of patches was tested on arm64 and x86. v4: -Removed bus: mhi: core: Introduce independent voting mechanism patch -Removed bus vote function from debugfs due to independent voting removal -Added helper resume APIs to aid consolidation of spread out code -Added a clean-up patch and a missing host resume in voting API v3: -Add patch to check for pending packets in suspend as a dependency for the independent voting mechanism introduction -Include register dump entry for debugfs to dump MHI, BHI, and BHIe registers -Update commit message for the debugfs patch -Updated Documentation/ABI with the required info for sysfs -Updated debugfs patch to include a new KConfig entry and dependencies -Updated reviewed-by for some patches v2: -Added a new debugfs.c file for specific debugfs entries and code -Updated commit text and addressed some comments for voting change -Made sure sysfs is only used for serial number and OEM PK hash usage Bhaumik Bhatt (9): bus: mhi: core: Remove double occurrence for mhi_ctrl_ev_task() declaration bus: mhi: core: Abort suspends due to outgoing pending packets bus: mhi: core: Use helper API to trigger a non-blocking host resume bus: mhi: core: Trigger a host resume when device vote is requested bus: mhi: core: Use generic name field for an MHI device bus: mhi: core: Introduce helper function to check device state bus: mhi: core: Introduce debugfs entries and counters for MHI bus: mhi: core: Read and save device hardware information from BHI bus: mhi: core: Introduce sysfs entries for MHI Documentation/ABI/stable/sysfs-bus-mhi | 25 ++ MAINTAINERS | 1 + drivers/bus/mhi/Kconfig | 8 + drivers/bus/mhi/core/Makefile | 5 +- drivers/bus/mhi/core/boot.c | 17 +- drivers/bus/mhi/core/debugfs.c | 444 +++++++++++++++++++++++++++++++++ drivers/bus/mhi/core/init.c | 65 ++++- drivers/bus/mhi/core/internal.h | 38 ++- drivers/bus/mhi/core/main.c | 27 +- drivers/bus/mhi/core/pm.c | 19 +- include/linux/mhi.h | 18 +- 11 files changed, 633 insertions(+), 34 deletions(-) create mode 100644 Documentation/ABI/stable/sysfs-bus-mhi create mode 100644 drivers/bus/mhi/core/debugfs.c