Re: [PATCH v9 00/11] Restructure the rpmsg_char driver and introduce rpmsg_ctrl driver

[Mathieu Poirier <mathieu.poirier@linaro.org>]

On Thu, Mar 24, 2022 at 06:36:23PM +0100, Arnaud POULIQUEN wrote:
> Hi Bjorn,
> 
> On 1/24/22 11:25, Arnaud Pouliquen wrote:
> > Updates from V8 [1]:
> > - rebase on 5.17-rc1 + rpmsg char cdev release fixes[2][3]
> > - updates based on Bjorn Andersson's comments:
> >   - remove rpmsg_create_default_ept API, set directly the ept->priv in rpmsg_chrdev_probe
> >     function.
> >   - rework commit message in [8/9]rpmsg: char: Introduce the "rpmsg-raw" channel
> > 
> > Patchset description:
> > 
> > The current rpmsg_char module implements a /dev/rpmsg_ctrl interface that provides the ability to
> > instantiate char devices (/dev/rpmsgX) associated with an rpmsg endpoint for communication with the
> > remote processor.
> > This implementation fits with QCOM rpmsg backend but not with the magement by chanel implemented
> > in the generic rpmsg virtio backend.
> > This series restructures the rpmsg_char driver to decorrelate the control part from the data part
> > in order to improve its compatible with the rpmsg virtio backend.
> > 
> > Objective:
> > - Expose a /dev/rpmsg_ctrlX interface for the application that is no longer dedicated to the
> >   rpmsg_char but generalized to all rpmsg services. This offers capability to create and destroy
> >   rpmsg channels from a user's application initiative (using the new RPMSG_CREATE_DEV_IOCTL and
> >   RPMSG_DESTROY_DEV_IOCTL controls).
> >   An application will be able to create/establish an rpmsg communication channel to communicate
> >   with the remote processor, and not only wait the remote processor initiative.
> >   This is interesting for example to establish a temporary communication link for diagnosis,
> >   calibration, debugging... or instantiate  new data flows on some user actions.
> > - Add capability to probe the rpmsg_char device at the initiative of the remote processor
> >  (rpmsg service announcement mechanism).
> >   This allows platforms based on the rpmsg virtio backend to create the /dev/rpmgX interface with
> >   a rpmsg name service announcement.
> > 
> > Subsets:
> >   - Extract the control part of the char dev and create the rpmsg_ctrl.c file (patches 1 to 6)
> >   - Introduce the "rpmsg-raw" channel in rpmsg_char(patches 7 to 10)
> >   - Introduce the RPMSG_CREATE_DEV_IOCTL IOCTL and RPMSG_DESTROY_DEV_IOCTL to instantiate RPMsg
> >     devices (patch 11)
> >     The application can then create or release a channel by specifying:
> >        - the name service of the device to instantiate.   
> >        - the source address.
> >        - the destination address.
> > 
> > This series has be applied and tested on 'commit e783362eb54c ("Linux 5.17-rc1") +
> > rpmsg_char cdev release fixes [2][3]
> > 
> > [1] https://lkml.org/lkml/2021/12/7/186
> > [2] https://lkml.org/lkml/2022/1/10/1129
> > [3] https://lkml.org/lkml/2022/1/10/1130
> > 
> > Arnaud Pouliquen (11):
> >   rpmsg: char: Export eptdev create and destroy functions
> >   rpmsg: Create the rpmsg class in core instead of in rpmsg char
> >   rpmsg: Move the rpmsg control device from rpmsg_char to rpmsg_ctrl
> 
> 
> >   arm: configs: Configs that had RPMSG_CHAR now get RPMSG_CTRL
> >   RISC-V: configs: Configs that had RPMSG_CHAR now get RPMSG_CTRL
> >   arm64: defconfig: Config that had RPMSG_CHAR now gets RPMSG_CTRL
> 
> Thank you for merging this series!
> 
> I can't see in the "for next" branch[1] the 3 patches above that update configs
> Are you expecting a specific action from me?   

Those patches will need to go through the Arm, RISC-V and arm64 subsystems.  The
mailing list for those subsystems has been CC'ed but that isn't enough to get
the maintainers' attention.  

I suggest sending another patchset with those 3 patches that CC the maintainers
directly.  For the Arm patch I suggest adding Linus Walleij.

Thanks,
Mathieu

> 
> [1]https://git.kernel.org/pub/scm/linux/kernel/git/remoteproc/linux.git
> 
> Regards,
> Arnaud
> 
> >   rpmsg: Update rpmsg_chrdev_register_device function
> >   rpmsg: char: Refactor rpmsg_chrdev_eptdev_create function
> >   rpmsg: char: Add possibility to use default endpoint of the rpmsg
> >     device
> >   rpmsg: char: Introduce the "rpmsg-raw" channel
> >   rpmsg: ctrl: Introduce new RPMSG_CREATE/RELEASE_DEV_IOCTL controls
> > 
> >  arch/arm/configs/qcom_defconfig   |   1 +
> >  arch/arm64/configs/defconfig      |   1 +
> >  arch/riscv/configs/defconfig      |   1 +
> >  arch/riscv/configs/rv32_defconfig |   1 +
> >  drivers/rpmsg/Kconfig             |   8 +
> >  drivers/rpmsg/Makefile            |   1 +
> >  drivers/rpmsg/qcom_glink_native.c |   2 +-
> >  drivers/rpmsg/qcom_smd.c          |   2 +-
> >  drivers/rpmsg/rpmsg_char.c        | 231 +++++++++++-----------------
> >  drivers/rpmsg/rpmsg_char.h        |  46 ++++++
> >  drivers/rpmsg/rpmsg_core.c        |  15 +-
> >  drivers/rpmsg/rpmsg_ctrl.c        | 243 ++++++++++++++++++++++++++++++
> >  drivers/rpmsg/rpmsg_internal.h    |  10 +-
> >  drivers/rpmsg/virtio_rpmsg_bus.c  |   2 +-
> >  include/uapi/linux/rpmsg.h        |  10 ++
> >  15 files changed, 419 insertions(+), 155 deletions(-)
> >  create mode 100644 drivers/rpmsg/rpmsg_char.h
> >  create mode 100644 drivers/rpmsg/rpmsg_ctrl.c
> >