Re: [RFC PATCH vs 2/4] drivers/input/joystick: sensehat: Raspberry Pi Sense HAT joystick driver

[nsaenzju]

On Fri, 2021-08-20 at 14:07 -0400, Charles Mirabile wrote:
> This patch implements support for the joystick.
> It supports left/right/up/down/enter attached via i2c
> 
> Signed-off-by: Charles Mirabile <cmirabil@xxxxxxxxxx>
> Signed-off-by: Mwesigwa Guma <mguma@xxxxxxxxxx>
> Signed-off-by: Joel Savitz <jsavitz@xxxxxxxxxx>
> ---
>  drivers/input/joystick/Kconfig             |   8 ++
>  drivers/input/joystick/Makefile            |   1 +
>  drivers/input/joystick/sensehat-joystick.c | 124 +++++++++++++++++++++
>  3 files changed, 133 insertions(+)
>  create mode 100644 drivers/input/joystick/sensehat-joystick.c
> 
> diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
> index 3b23078bc7b5..d2f78353b74c 100644
> --- a/drivers/input/joystick/Kconfig
> +++ b/drivers/input/joystick/Kconfig
> @@ -399,4 +399,12 @@ config JOYSTICK_N64
>  	  Say Y here if you want enable support for the four
>  	  built-in controller ports on the Nintendo 64 console.
>  
> +config JOYSTICK_SENSEHAT
> +	tristate "Raspberry Pi Sense HAT joystick"
> +	depends on GPIOLIB && INPUT
> +	select MFD_SENSEHAT_CORE
> +
> +	help
> +	  This is the joystick driver for the Raspberry Pi Sense HAT
> +
>  endif
> diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
> index 5174b8aba2dd..39c8b5c6e5ae 100644
> --- a/drivers/input/joystick/Makefile
> +++ b/drivers/input/joystick/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_JOYSTICK_N64)		+= n64joy.o
>  obj-$(CONFIG_JOYSTICK_PSXPAD_SPI)	+= psxpad-spi.o
>  obj-$(CONFIG_JOYSTICK_PXRC)		+= pxrc.o
>  obj-$(CONFIG_JOYSTICK_QWIIC)		+= qwiic-joystick.o
> +obj-$(CONFIG_JOYSTICK_SENSEHAT)         += sensehat-joystick.o
>  obj-$(CONFIG_JOYSTICK_SIDEWINDER)	+= sidewinder.o
>  obj-$(CONFIG_JOYSTICK_SPACEBALL)	+= spaceball.o
>  obj-$(CONFIG_JOYSTICK_SPACEORB)		+= spaceorb.o
> diff --git a/drivers/input/joystick/sensehat-joystick.c b/drivers/input/joystick/sensehat-joystick.c
> new file mode 100644
> index 000000000000..4aca125bc29d
> --- /dev/null
> +++ b/drivers/input/joystick/sensehat-joystick.c
> @@ -0,0 +1,124 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * Raspberry Pi Sense HAT joystick driver
> + * http://raspberrypi.org
> + *
> + * Copyright (C) 2015 Raspberry Pi
> + * Copyright (C) 2021 Charles Mirabile, Mwesigwa Guma, Joel Savitz
> + *
> + * Original Author: Serge Schneider
> + * Revised for upstream Linux by: Charles Mirabile, Mwesigwa Guma, Joel Savitz
> + */
> +
> +#include <linux/module.h>
> +#include <linux/input.h>
> +#include <linux/i2c.h>
> +#include <linux/interrupt.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/platform_device.h>
> +
> +#include <linux/mfd/sensehat.h>
> +
> +static unsigned char keymap[] = {KEY_DOWN, KEY_RIGHT, KEY_UP, KEY_ENTER, KEY_LEFT,};

I'm not sure devices outputing KEY_* events fits input/joystick. Maybe
input/misc or input/keyboard? Or else use 'BTN_DPAD_UP/DOWN/LEFT/RIGHT'. Which
is what game controllers seem to do.

Regards,
Nicolas