[v13,0/2] Add support for USB Type-C interface on latest NVIDIA GPU

Message

Ajay Gupta Oct. 3, 2018, 6:27 p.m. UTC

Hi Heikki and Wolfram,

These two changes add support for USB Type-C interface on latest NVIDIA GPU card.
The Type-C controller used is Cypress CCGx and is over I2C interface.

I2C host controller has known limitation of sending STOP after every read. Since
each read can be of 4 byte maximum length so there is a limit of 4 byte read.
This is mentioned in adapter quirks as "max_read_len = 4"

I2C host controller is mainly used for "write-then-read" or "write" messages so added
the flag I2C_AQ_COMB_WRITE_THEN_READ in adapter quirks.

I think the patches should through usb tree because the main functionality is
usb Type-C.

The changes have been reviewed by Andy Shevchenko and Heikki Krogerus.
Peter Rosin also helped review the patches and provided valuable comments.
Thanks to all reviewers.

Thanks
Ajay

Ajay Gupta (2):
  i2c: buses: add i2c bus driver for NVIDIA GPU
  usb: typec: ucsi: add support for Cypress CCGx

 Documentation/i2c/busses/i2c-nvidia-gpu |  18 ++
 MAINTAINERS                             |   7 +
 drivers/i2c/busses/Kconfig              |   9 +
 drivers/i2c/busses/Makefile             |   1 +
 drivers/i2c/busses/i2c-nvidia-gpu.c     | 369 ++++++++++++++++++++++++++++++++
 drivers/usb/typec/ucsi/Kconfig          |  10 +
 drivers/usb/typec/ucsi/Makefile         |   2 +
 drivers/usb/typec/ucsi/ucsi_ccg.c       | 305 ++++++++++++++++++++++++++
 8 files changed, 721 insertions(+)
 create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu
 create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c
 create mode 100644 drivers/usb/typec/ucsi/ucsi_ccg.c

Comments

Ajay Gupta Oct. 12, 2018, 6 p.m. UTC | #1

Hi Heikki and Wolfram
Do you have any comments on these changes?

Regards,
Ajay

--nvpublic
> Hi Heikki and Wolfram,
> 
> These two changes add support for USB Type-C interface on latest NVIDIA GPU
> card.
> The Type-C controller used is Cypress CCGx and is over I2C interface.
> 
> I2C host controller has known limitation of sending STOP after every read.
> Since each read can be of 4 byte maximum length so there is a limit of 4 byte
> read.
> This is mentioned in adapter quirks as "max_read_len = 4"
> 
> I2C host controller is mainly used for "write-then-read" or "write" messages
> so added the flag I2C_AQ_COMB_WRITE_THEN_READ in adapter quirks.
> 
> I think the patches should through usb tree because the main functionality is
> usb Type-C.
> 
> The changes have been reviewed by Andy Shevchenko and Heikki Krogerus.
> Peter Rosin also helped review the patches and provided valuable comments.
> Thanks to all reviewers.
> 
> Thanks
> Ajay
> 
> Ajay Gupta (2):
>   i2c: buses: add i2c bus driver for NVIDIA GPU
>   usb: typec: ucsi: add support for Cypress CCGx
> 
>  Documentation/i2c/busses/i2c-nvidia-gpu |  18 ++
>  MAINTAINERS                             |   7 +
>  drivers/i2c/busses/Kconfig              |   9 +
>  drivers/i2c/busses/Makefile             |   1 +
>  drivers/i2c/busses/i2c-nvidia-gpu.c     | 369
> ++++++++++++++++++++++++++++++++
>  drivers/usb/typec/ucsi/Kconfig          |  10 +
>  drivers/usb/typec/ucsi/Makefile         |   2 +
>  drivers/usb/typec/ucsi/ucsi_ccg.c       | 305 ++++++++++++++++++++++++++
>  8 files changed, 721 insertions(+)
>  create mode 100644 Documentation/i2c/busses/i2c-nvidia-gpu
>  create mode 100644 drivers/i2c/busses/i2c-nvidia-gpu.c
>  create mode 100644 drivers/usb/typec/ucsi/ucsi_ccg.c
> 
> --
> 2.7.4

Heikki Krogerus Oct. 16, 2018, 3:29 p.m. UTC | #2

+Andy

These have changed a bit since Andy gave his review.

On Fri, Oct 12, 2018 at 06:00:50PM +0000, Ajay Gupta wrote:
> Hi Heikki and Wolfram
> Do you have any comments on these changes?

Let me take one more look at the UCSI driver, just in case. Nothing's
probable going to happen for a while in any case as the merge window
is about to open.


thanks,