Re: [PATCH V6] scsi: ufs: Add configfs support for UFS provisioning

[Adrian Hunter]

On 16/07/18 12:43, Sayali Lokhande wrote:
> This patch adds configfs support to provision UFS device at
> runtime. This feature can be primarily useful in factory or
> assembly line as some devices may be required to be configured
> multiple times during initial system development phase.
> Configuration Descriptors can be written multiple times until
> bConfigDescrLock attribute is zero.
> 
> Configuration descriptor buffer consists of Device and Unit
> descriptor configurable parameters which are parsed from vendor
> specific provisioning file and then passed via configfs node at
> runtime to provision ufs device.
> CONFIG_CONFIGFS_FS needs to be enabled for using this feature.
> 
> Usage:
> 1) To read current configuration descriptor :
>    cat /config/XXXX.ufshc/ufs_provision
> 2) To provision ufs device:
>    echo <config_desc_buf> > /config/XXXX.ufshc/ufs_provision
> 
> Signed-off-by: Sayali Lokhande <sayalil@xxxxxxxxxxxxxx>
> ---
>  Documentation/ABI/testing/configfs-driver-ufs |  18 +++
>  drivers/scsi/ufs/Kconfig                      |  10 ++
>  drivers/scsi/ufs/Makefile                     |   1 +
>  drivers/scsi/ufs/ufs-configfs.c               | 162 ++++++++++++++++++++++++++
>  drivers/scsi/ufs/ufshcd.c                     |   2 +
>  drivers/scsi/ufs/ufshcd.h                     |  19 +++
>  6 files changed, 212 insertions(+)
>  create mode 100644 Documentation/ABI/testing/configfs-driver-ufs
>  create mode 100644 drivers/scsi/ufs/ufs-configfs.c
> 
> diff --git a/Documentation/ABI/testing/configfs-driver-ufs b/Documentation/ABI/testing/configfs-driver-ufs
> new file mode 100644
> index 0000000..eeee499c
> --- /dev/null
> +++ b/Documentation/ABI/testing/configfs-driver-ufs
> @@ -0,0 +1,18 @@
> +What:		/config/ufshcd/ufs_provision
> +Date:		Jun 2018
> +KernelVersion:	4.14
> +Description:
> +		This file shows the current ufs configuration descriptor set in device.
> +		This can be used to provision ufs device if bConfigDescrLock is 0.
> +		For more details, refer 14.1.6.3 Configuration Descriptor and
> +		Table 14-12 - Unit Descriptor configurable parameters from specs for
> +		description of each configuration descriptor parameter.
> +		Configuration descriptor buffer needs to be passed in space separated
> +		format specificied as below:
> +		echo <bLength> <bDescriptorIDN> <bConfDescContinue> <bBootEnable>
> +		<bDescrAccessEn> <bInitPowerMode> <bHighPriorityLUN>
> +		<bSecureRemovalType> <bInitActiveICCLevel> <wPeriodicRTCUpdate>
> +		<0Bh:0Fh_ReservedAs_0> <bLUEnable> <bBootLunID> <bLUWriteProtect>
> +		<bMemoryType> <dNumAllocUnits> <bDataReliability> <bLogicalBlockSize>
> +		<bProvisioningType> <wContextCapabilities> <0Dh:0Fh_ReservedAs_0>
> +		> /config/XXXX.ufshc/ufs_provision
> diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
> index e27b4d4..34d89c2 100644
> --- a/drivers/scsi/ufs/Kconfig
> +++ b/drivers/scsi/ufs/Kconfig
> @@ -100,3 +100,13 @@ config SCSI_UFS_QCOM
>  
>  	  Select this if you have UFS controller on QCOM chipset.
>  	  If unsure, say N.
> +
> +config UFS_PROVISION
> +	tristate "Runtime UFS Provisioning support"
> +	depends on SCSI_UFSHCD_PLATFORM && CONFIGFS_FS

Why SCSI_UFSHCD_PLATFORM instead of SCSI_UFSHCD?

Also please cc me in future revisions.