[PATCH] Update libinput to support evdev driver v1.2

[Peter Hutterer]

On Wed, Oct 19, 2016 at 07:05:13PM -0700, Deepa Dinamani wrote:
> Update input event structures read from the kernel to match
> the 1.2 version of the driver.
> 
> There are no changes to the exposed interfaces of libinput.
> 
> Note that the patch goes along with the changes to libevdev
> and mtdev to support the updated kernel driver.
> 
> The associated kernel driver change is proposed at
> https://lkml.org/lkml/2016/10/17/1146 .
> 
> Signed-off-by: Deepa Dinamani <deepa.kernel at gmail.com>
> ---
>  include/linux/input.h | 49 +++++++++++++++++++++++++++++++++++++++++++++++--
>  src/evdev.c           |  4 ++--
>  2 files changed, 49 insertions(+), 4 deletions(-)
> 
> diff --git a/include/linux/input.h b/include/linux/input.h
> index 4bf3d6d..202798a 100644
> --- a/include/linux/input.h
> +++ b/include/linux/input.h
> @@ -13,10 +13,29 @@
>  #include <sys/types.h>
>  #include <linux/types.h>
>  
> -/*
> - * The event structure itself
> +/* The time structure for y2038 safe raw_input_event.
> + * The fields use unsigned types to extend times until
> + * year 2106 rather than 2038.
>   */
> +struct input_timeval {
> +	__kernel_ulong_t tv_sec;
> +	__kernel_ulong_t tv_usec;
> +};
> +
> +struct raw_input_event {
> +	struct input_timeval time;
> +	__u16 type;
> +	__u16 code;
> +	__s32 value;
> +};
> +
> +#ifndef __KERNEL__
>  
> +/* Userspace structure.
> + * Definition maintained here for userspace that is not yet updated to use
> + * struct raw_input_event.
> + * Not to be used anywhere within the kernel.
> + */
>  struct input_event {
>  	struct timeval time;
>  	__u16 type;
> @@ -24,11 +43,37 @@ struct input_event {
>  	__s32 value;
>  };
>  
> +
> +static inline void
> +raw_input_to_input_event(const struct raw_input_event *raw, struct input_event *ev)
> +{
> +	ev->time.tv_sec = raw->time.tv_sec;
> +	ev->time.tv_usec = raw->time.tv_usec;
> +	ev->type = raw->type;
> +	ev->code = raw->code;
> +	ev->value = raw->value;
> +}
> +
> +static inline void
> +input_to_raw_event(const struct input_event *ev, struct raw_input_event *raw)
> +{
> +	raw->time.tv_sec = ev->time.tv_sec;
> +	raw->time.tv_usec = ev->time.tv_usec;
> +	raw->type = ev->type;
> +	raw->code = ev->code;
> +	raw->value = ev->value;
> +}
> +
> +#endif
> +
> +
>  /*
>   * Protocol version.
>   */
>  
>  #define EV_VERSION		0x010001
> +#define EV_VERSION_1_2         0x010002
> +
>  
>  /*
>   * IOCTLs (0x00 - 0x7f)
> diff --git a/src/evdev.c b/src/evdev.c
> index f7f7230..5d47119 100644
> --- a/src/evdev.c
> +++ b/src/evdev.c
> @@ -256,7 +256,7 @@ evdev_device_led_update(struct evdev_device *device, enum libinput_led leds)
>  		{ LIBINPUT_LED_CAPS_LOCK, LED_CAPSL },
>  		{ LIBINPUT_LED_SCROLL_LOCK, LED_SCROLLL },
>  	};
> -	struct input_event ev[ARRAY_LENGTH(map) + 1];
> +	struct raw_input_event ev[ARRAY_LENGTH(map) + 1];
>  	unsigned int i;
>  
>  	if (!(device->seat_caps & EVDEV_DEVICE_KEYBOARD))
> @@ -2665,7 +2665,7 @@ evdev_set_device_group(struct evdev_device *device,
>  static inline void
>  evdev_drain_fd(int fd)
>  {
> -	struct input_event ev[24];
> +	struct raw_input_event ev[24];

don't we need some version detection here? what's the effect of writing new
structs to old kernels, other than lighting up LEDs that shouldn't be lit?

Cheers,
   Peter

>  	size_t sz = sizeof ev;
>  
>  	while (read(fd, &ev, sz) == (int)sz) {
> -- 
> 2.7.4