Re: [PATCH v2] treewide, serdev: change receive_buf() return type to size_t

[Rob Herring <robh@xxxxxxxxxx>]

On Mon, Jan 22, 2024 at 12:06 PM Francesco Dolcini <francesco@xxxxxxxxxx> wrote:
>
> From: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
>
> receive_buf() is called from ttyport_receive_buf() that expects values
> ">= 0" from serdev_controller_receive_buf(), change its return type from
> ssize_t to size_t.
>
> The need for this clean-up was noticed while fixing a warning, see
> commit 94d053942544 ("Bluetooth: btnxpuart: fix recv_buf() return value").
> Changing the callback prototype to return an unsigned seems the best way
> to document the API and ensure that is properly used.
>
> GNSS drivers implementation of serdev receive_buf() callback return
> directly the return value of gnss_insert_raw(). gnss_insert_raw()
> returns a signed int, however this is not an issue since the value
> returned is always positive, because of the kfifo_in() implementation.
> gnss_insert_raw() could be changed to return also an unsigned, however
> this is not implemented here as request by the GNSS maintainer Johan
> Hovold.
>
> Suggested-by: Jiri Slaby <jirislaby@xxxxxxxxxx>
> Link: https://lore.kernel.org/all/087be419-ec6b-47ad-851a-5e1e3ea5cfcc@xxxxxxxxxx/
> Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
> Acked-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> #for-iio
> ---
> v1:
>  - https://lore.kernel.org/all/20231214170146.641783-1-francesco@xxxxxxxxxx/
> v2:
>  - rebased on 6.8-rc1
>  - add acked-by Jonathan
>  - do not change gnss_insert_raw()
>  - do not change the code style of the gnss code
>  - commit message improvements, explain the reasons for doing only minimal
>    changes on the GNSS part
> ---
>  drivers/bluetooth/btmtkuart.c              |  4 ++--
>  drivers/bluetooth/btnxpuart.c              |  4 ++--
>  drivers/bluetooth/hci_serdev.c             |  4 ++--
>  drivers/gnss/serial.c                      |  2 +-
>  drivers/gnss/sirf.c                        |  2 +-
>  drivers/greybus/gb-beagleplay.c            |  6 +++---
>  drivers/iio/chemical/pms7003.c             |  4 ++--
>  drivers/iio/chemical/scd30_serial.c        |  4 ++--
>  drivers/iio/chemical/sps30_serial.c        |  4 ++--
>  drivers/iio/imu/bno055/bno055_ser_core.c   |  4 ++--
>  drivers/mfd/rave-sp.c                      |  4 ++--
>  drivers/net/ethernet/qualcomm/qca_uart.c   |  2 +-
>  drivers/nfc/pn533/uart.c                   |  4 ++--
>  drivers/nfc/s3fwrn5/uart.c                 |  4 ++--
>  drivers/platform/chrome/cros_ec_uart.c     |  4 ++--
>  drivers/platform/surface/aggregator/core.c |  4 ++--
>  drivers/tty/serdev/serdev-ttyport.c        | 10 ++++------
>  include/linux/serdev.h                     |  8 ++++----
>  sound/drivers/serial-generic.c             |  4 ++--
>  19 files changed, 40 insertions(+), 42 deletions(-)

Reviewed-by: Rob Herring <robh@xxxxxxxxxx>