[v2,0/7] usb: typec: ucsi: rework glue driver interface

Message

Dmitry Baryshkov June 20, 2024, 10:55 p.m. UTC

The interface between UCSI and the glue driver is very low-level. It
allows reading the UCSI data from any offset (but in reality the UCSI
driver reads only VERSION, CCI an MESSAGE_IN data). All event handling
is to be done by the glue driver (which already resulted in several
similar-but-slightly different implementations). It leaves no place to
optimize the write-read-read sequence for the command execution (which
might be beneficial for some of the drivers), etc.

The patchseries attempts to restructure the UCSI glue driver interface
in order to provide sensible operations instead of a low-level read /
write calls.

If this approach is found to be acceptable, I plan to further rework the
command interface, moving reading CCI and MESSAGE_IN to the common
control code, which should simplify driver's implementation and remove
necessity to split quirks between sync_control and read_message_in e.g.
as implemented in the ucsi_ccg.c.

Note, the series was tested only on the ucsi_glink platforms. Further
testing is appreciated.

Depends: [1], [2]

[1] https://lore.kernel.org/linux-usb/[e-mail]/

[2] https://lore.kernel.org/linux-usb/[e-mail]/

Signed-off-by: Dmitry Baryshkov <[e-mail]>
---
Changes in v2:
- Dropped the RFC prefix
- Rebased on top of the fixed STM32 patch
- Included the pending Yoga C630 driver into the cleanup.
- Link to v1: https://lore.kernel.org/r/[e-mail]

---
Dmitry Baryshkov (7):
      usb: typec: ucsi: move ucsi_acknowledge() from ucsi_read_error()
      usb: typec: ucsi: simplify command sending API
      usb: typec: ucsi: split read operation
      usb: typec: ucsi: rework command execution functions
      usb: typec: ucsi: inline ucsi_read_message_in
      usb: typec: ucsi: extract common code for command handling
      usb: typec: ucsi: reorder operations in ucsi_run_command()

 drivers/usb/typec/ucsi/ucsi.c           | 215 +++++++++++++++++---------------
 drivers/usb/typec/ucsi/ucsi.h           |  26 ++--
 drivers/usb/typec/ucsi/ucsi_acpi.c      | 100 +++++++--------
 drivers/usb/typec/ucsi/ucsi_ccg.c       | 103 +++++++--------
 drivers/usb/typec/ucsi/ucsi_glink.c     |  74 ++++-------
 drivers/usb/typec/ucsi/ucsi_stm32g0.c   |  79 ++++--------
 drivers/usb/typec/ucsi/ucsi_yoga_c630.c | 104 +++++----------
 7 files changed, 309 insertions(+), 392 deletions(-)
---
base-commit: f0dbf09a40c8100a895f675d619db5ed1f58f7ac
change-id: 20240525-ucsi-rework-interface-5ff2264f6aec

Best regards,

Comments

Heikki Krogerus June 25, 2024, 2:28 p.m. UTC | #1

On Fri, Jun 21, 2024 at 01:55:19AM +0300, Dmitry Baryshkov wrote:
> The interface between UCSI and the glue driver is very low-level. It
> allows reading the UCSI data from any offset (but in reality the UCSI
> driver reads only VERSION, CCI an MESSAGE_IN data). All event handling
> is to be done by the glue driver (which already resulted in several
> similar-but-slightly different implementations). It leaves no place to
> optimize the write-read-read sequence for the command execution (which
> might be beneficial for some of the drivers), etc.
> 
> The patchseries attempts to restructure the UCSI glue driver interface
> in order to provide sensible operations instead of a low-level read /
> write calls.
> 
> If this approach is found to be acceptable, I plan to further rework the
> command interface, moving reading CCI and MESSAGE_IN to the common
> control code, which should simplify driver's implementation and remove
> necessity to split quirks between sync_control and read_message_in e.g.
> as implemented in the ucsi_ccg.c.
> 
> Note, the series was tested only on the ucsi_glink platforms. Further
> testing is appreciated.

I can run a few tests against these tomorrow.

I don't have have any objections with this approach, but you'll need
to do another rebase. Now these don't apply cleanly because of
9e3caa9dd51b ("usb: typec: ucsi_acpi: Add LG Gram quirk").

thanks,

> Depends: [1], [2]
> 
> [1] https://lore.kernel.org/linux-usb/[e-mail]/
> 
> [2] https://lore.kernel.org/linux-usb/[e-mail]/
> 
> Signed-off-by: Dmitry Baryshkov <[e-mail]>
> ---
> Changes in v2:
> - Dropped the RFC prefix
> - Rebased on top of the fixed STM32 patch
> - Included the pending Yoga C630 driver into the cleanup.
> - Link to v1: https://lore.kernel.org/r/[e-mail]
> 
> ---
> Dmitry Baryshkov (7):
>       usb: typec: ucsi: move ucsi_acknowledge() from ucsi_read_error()
>       usb: typec: ucsi: simplify command sending API
>       usb: typec: ucsi: split read operation
>       usb: typec: ucsi: rework command execution functions
>       usb: typec: ucsi: inline ucsi_read_message_in
>       usb: typec: ucsi: extract common code for command handling
>       usb: typec: ucsi: reorder operations in ucsi_run_command()
> 
>  drivers/usb/typec/ucsi/ucsi.c           | 215 +++++++++++++++++---------------
>  drivers/usb/typec/ucsi/ucsi.h           |  26 ++--
>  drivers/usb/typec/ucsi/ucsi_acpi.c      | 100 +++++++--------
>  drivers/usb/typec/ucsi/ucsi_ccg.c       | 103 +++++++--------
>  drivers/usb/typec/ucsi/ucsi_glink.c     |  74 ++++-------
>  drivers/usb/typec/ucsi/ucsi_stm32g0.c   |  79 ++++--------
>  drivers/usb/typec/ucsi/ucsi_yoga_c630.c | 104 +++++----------
>  7 files changed, 309 insertions(+), 392 deletions(-)
> ---
> base-commit: f0dbf09a40c8100a895f675d619db5ed1f58f7ac
> change-id: 20240525-ucsi-rework-interface-5ff2264f6aec
> 
> Best regards,
> -- 
> Dmitry Baryshkov <[e-mail]>