Re: [RESEND PATCH v10 0/3] fpga: Use standard class dev_release function

[Tom Rix <trix@redhat.com>]

On 7/27/21 9:38 AM, Russ Weight wrote:
>
> On 7/27/21 9:22 AM, Tom Rix wrote:
>> On 7/27/21 9:15 AM, Russ Weight wrote:
>>> On 7/27/21 6:24 AM, Tom Rix wrote:
>>>> On 7/26/21 2:33 PM, Russ Weight wrote:
>>>>> Hi Moritz,
>>>>>
>>>>> I sent this version of the patchset out on July 8th. The only discussion has
>>>>> been around the compat-id structure. I think there is agreement that this can
>>>>> be treated separately. What are your thoughts? Do you think this patchset is
>>>>> ready?
>>>> While I agree the compat_id can be treated separately, i still have a problem with the 2 register functions.
>>>>
>>>> In this discussion,
>>>>
>>>> https://lore.kernel.org/linux-fpga/DM6PR11MB38194D113950FA4B75C7F2C485E49@DM6PR11MB3819.namprd11.prod.outlook.com/
>>>>
>>>> *register_full(..., *info) becomes
>>>>
>>>> *register(..., *info)
>>>>
>>>> and
>>>>
>>>> *register_simple() is moved out of the public api and becomes private to the subsystem.
>>> Somehow I missed that part of the email. I'm not sure I understand the part about
>>> register_simple() "becomes private to the subsystem". Most users would call the simple
>>> version of the API. Is the proposal to replicate the register_simple() interface
>>> for each driver that calls it?
>> Still use *register_simple() internally, so most of your patchset is unchanged.
>>
>> Move it out the public api. include/linux/fpga-mgr.h into someplace appropriate in drivers/fpga/
> Ok - I'll do another spin of the patch set.
>
> Just to be clear, *register_full() gets renamed back to *register(). The current *register()
> goes back to *register_simple(). *register_simple() is an exported symbol, but the function
> prototype moves out of the public header file into private header file under drivers/fpga.

Mostly.

If register_simple does not need to be exported, it shouldn't be.

Tom

>
> - Russ
>
>> Tom
>>
>>>> Tom
>>>>
>>>>> Thanks,
>>>>> - Russ
>>>>>
>>>>>
>>>>> On 7/26/21 2:27 PM, Russ Weight wrote:
>>>>>> The FPGA framework has a convention of using managed resource functions
>>>>>> to allow parent drivers to manage the data structures allocated by the
>>>>>> class drivers. They use an empty *_dev_release() function to satisfy the
>>>>>> class driver.
>>>>>>
>>>>>> This is inconsistent with linux driver model.
>>>>>>
>>>>>> These changes remove the managed resource functions and populate the class
>>>>>> dev_release callback functions. They also merge the create() and register()
>>>>>> functions into a single register() or register_full() function for each of
>>>>>> the fpga-mgr, fpga-region, and fpga-bridge class drivers.
>>>>>>
>>>>>> The new *register_full() functions accept an info data structure to provide
>>>>>> flexibility in passing optional parameters. The *register() functions
>>>>>> support the legacy parameter list for users that don't require the use of
>>>>>> optional parameters.
>>>>>>
>>>>>> For more context, refer to this email thread:
>>>>>>
>>>>>> https://marc.info/?l=linux-fpga&m=162127412218557&w=2
>>>>>>
>>>>>> I turned on the configs assocated with each of the modified files, but I
>>>>>> must have been missing some dependencies, because not all of them compiled.
>>>>>> I did a run-time test specifically with the dfl-fme infrastructure. This
>>>>>> would have exercised the region, bridge, and fpga-mgr frameworks.
>>>>>>
>>>>>> Changelog v9 -> v10:
>>>>>>      - Fixed commit messages to reference register_full() instead of
>>>>>>        register_simple().
>>>>>>      - Removed the fpga_bridge_register_full() function, because there is
>>>>>>        not need for it yet. Updated the documentation and commit message
>>>>>>        accordingly.
>>>>>>      - Updated documentation to reference the fpga_manager_info and
>>>>>>        fpga_region_info structures.
>>>>>>
>>>>>> Changelog v8 -> v9:
>>>>>>      - Cleaned up documentation for the FPGA Manager, Bridge, and Region
>>>>>>        register functions
>>>>>>      - Renamed fpga_*_register() to fpga_*_register_full()
>>>>>>      - Renamed fpga_*_register_simple() to fpga_*_register()
>>>>>>      - Renamed devm_fpga_mgr_register() to devm_fpga_mgr_register_full()
>>>>>>      - Renamed devm_fpga_mgr_register_simple() to devm_fpga_mgr_register()
>>>>>>
>>>>>> Changelog v7 -> v8:
>>>>>>      - Added reviewed-by tags.
>>>>>>      - Updated Documentation/driver-api/fpga/ files: fpga-mgr.rst,
>>>>>>        fpga-bridge.rst, and fpga-region.rst.
>>>>>>
>>>>>> Changelog v6 -> v7:
>>>>>>      - Update the commit messages to describe the new parameters for the
>>>>>>        *register() functions and to mention the *register_simple() functions.
>>>>>>      - Fix function prototypes in header file to rename dev to parent.
>>>>>>      - Make use of the PTR_ERR_OR_ZERO() macro when possible.
>>>>>>      - Some cleanup of comments.
>>>>>>      - Update function definitions/prototypes to apply const to the new info
>>>>>>        parameter.
>>>>>>      - Verify that info->br_ops is non-null in the fpga_bridge_register()
>>>>>>        function.
>>>>>>      - Verify a non-null info pointer in the fpga_region_register() function.
>>>>>>
>>>>>> Changelog v5 -> v6:
>>>>>>      - Moved FPGA manager/bridge/region optional parameters out of the ops
>>>>>>        structure and back into the FPGA class driver structure.
>>>>>>      - Changed fpga_*_register() function parameters to accept an info data
>>>>>>        structure to provide flexibility in passing optional parameters.
>>>>>>      - Added fpga_*_register_simple() functions to support current parameters
>>>>>>        for users that don't require use of optional parameters.
>>>>>>
>>>>>> Changelog v4 -> v5:
>>>>>>      - Rebased on top of recently accepted patches.
>>>>>>      - Removed compat_id from the fpga_mgr_register() parameter list
>>>>>>        and added it to the fpga_manager_ops structure. This also required
>>>>>>        dynamically allocating the dfl-fme-ops structure in order to add
>>>>>>        the appropriate compat_id.
>>>>>>      - Created the fpga_region_ops data structure which is optionally passed
>>>>>>        to fpga_region_register(). compat_id, the get_bridges() pointer, and
>>>>>>        the priv pointer are included in the fpga_region_ops structure.
>>>>>>
>>>>>> Changelog v3 -> v4:
>>>>>>      - Added the compat_id parameter to fpga_mgr_register() and
>>>>>>        devm_fpga_mgr_register() to ensure that the compat_id is set before
>>>>>>        the device_register() call.
>>>>>>      - Added the compat_id parameter to fpga_region_register() to ensure
>>>>>>        that the compat_id is set before the device_register() call.
>>>>>>      - Modified the dfl_fpga_feature_devs_enumerate() function to restore
>>>>>>        the fpga_region_register() call to the correct location.
>>>>>>
>>>>>> Changelog v2 -> v3:
>>>>>>      - Cleaned up comment headers for fpga_mgr_register(), fpga_bridge_register(),
>>>>>>        and fpga_region_register().
>>>>>>      - Fixed error return on ida_simple_get() failure for fpga_mgr_register(),
>>>>>>        fpga_bridge_register(), and fpga_region_register().
>>>>>>      - Fixed error return value for fpga_bridge_register(): ERR_PTR(ret) instead
>>>>>>        of NULL.
>>>>>>
>>>>>> Changelog v1 -> v2:
>>>>>>      - Restored devm_fpga_mgr_register() functionality to the fpga-mgr
>>>>>>        class driver, adapted for the combined create/register functionality.
>>>>>>      - All previous callers of devm_fpga_mgr_register() will continue to call
>>>>>>        devm_fpga_mgr_register().
>>>>>>      - replaced unnecessary ternary operators in return statements with
>>>>>>        standard if conditions.
>>>>>>
>>>>>> Russ Weight (3):
>>>>>>      fpga: mgr: Use standard dev_release for class driver
>>>>>>      fpga: bridge: Use standard dev_release for class driver
>>>>>>      fpga: region: Use standard dev_release for class driver
>>>>>>
>>>>>>     Documentation/driver-api/fpga/fpga-bridge.rst |   6 +-
>>>>>>     Documentation/driver-api/fpga/fpga-mgr.rst    |  38 +++-
>>>>>>     Documentation/driver-api/fpga/fpga-region.rst |  12 +-
>>>>>>     drivers/fpga/altera-cvp.c                     |  12 +-
>>>>>>     drivers/fpga/altera-fpga2sdram.c              |  12 +-
>>>>>>     drivers/fpga/altera-freeze-bridge.c           |  10 +-
>>>>>>     drivers/fpga/altera-hps2fpga.c                |  12 +-
>>>>>>     drivers/fpga/altera-pr-ip-core.c              |   7 +-
>>>>>>     drivers/fpga/altera-ps-spi.c                  |   9 +-
>>>>>>     drivers/fpga/dfl-fme-br.c                     |  10 +-
>>>>>>     drivers/fpga/dfl-fme-mgr.c                    |  22 +-
>>>>>>     drivers/fpga/dfl-fme-region.c                 |  17 +-
>>>>>>     drivers/fpga/dfl.c                            |  12 +-
>>>>>>     drivers/fpga/fpga-bridge.c                    | 122 +++-------
>>>>>>     drivers/fpga/fpga-mgr.c                       | 215 ++++++++----------
>>>>>>     drivers/fpga/fpga-region.c                    | 119 ++++------
>>>>>>     drivers/fpga/ice40-spi.c                      |   9 +-
>>>>>>     drivers/fpga/machxo2-spi.c                    |   9 +-
>>>>>>     drivers/fpga/of-fpga-region.c                 |  10 +-
>>>>>>     drivers/fpga/socfpga-a10.c                    |  16 +-
>>>>>>     drivers/fpga/socfpga.c                        |   9 +-
>>>>>>     drivers/fpga/stratix10-soc.c                  |  16 +-
>>>>>>     drivers/fpga/ts73xx-fpga.c                    |   9 +-
>>>>>>     drivers/fpga/xilinx-pr-decoupler.c            |  17 +-
>>>>>>     drivers/fpga/xilinx-spi.c                     |  11 +-
>>>>>>     drivers/fpga/zynq-fpga.c                      |  16 +-
>>>>>>     drivers/fpga/zynqmp-fpga.c                    |   9 +-
>>>>>>     include/linux/fpga/fpga-bridge.h              |  30 ++-
>>>>>>     include/linux/fpga/fpga-mgr.h                 |  62 +++--
>>>>>>     include/linux/fpga/fpga-region.h              |  36 ++-
>>>>>>     30 files changed, 383 insertions(+), 511 deletions(-)
>>>>>>