diff mbox series

[v2,2/7] Input: make sure input handlers define only one processing method

Message ID 20240703213756.3375978-3-dmitry.torokhov@gmail.com
State Accepted
Commit a184cf98b1d4397fe7eca881da596059fea36a18
Headers show
Series Simplify event handling logic in input core | expand

Commit Message

Dmitry Torokhov July 3, 2024, 9:37 p.m. UTC
Input core expects input handlers to be either filters, or regular
handlers, but not both. Additionally, for regular handlers it does
not make sense to define both single event method and batch method.

Refuse registering handler if it defines more than one method.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/input.c | 24 ++++++++++++++++++++++++
 1 file changed, 24 insertions(+)

Comments

Jeff LaBundy July 7, 2024, 7:53 p.m. UTC | #1
Hi Dmitry,

On Wed, Jul 03, 2024 at 02:37:49PM -0700, Dmitry Torokhov wrote:
> Input core expects input handlers to be either filters, or regular
> handlers, but not both. Additionally, for regular handlers it does
> not make sense to define both single event method and batch method.
> 
> Refuse registering handler if it defines more than one method.
> 
> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Reviewed-by: Jeff LaBundy <jeff@labundy.com>

> ---
>  drivers/input/input.c | 24 ++++++++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/drivers/input/input.c b/drivers/input/input.c
> index fd4997ba263c..7e4f8824f4fd 100644
> --- a/drivers/input/input.c
> +++ b/drivers/input/input.c
> @@ -2517,6 +2517,26 @@ void input_unregister_device(struct input_dev *dev)
>  }
>  EXPORT_SYMBOL(input_unregister_device);
>  
> +static int input_handler_check_methods(const struct input_handler *handler)
> +{
> +	int count = 0;
> +
> +	if (handler->filter)
> +		count++;
> +	if (handler->events)
> +		count++;
> +	if (handler->event)
> +		count++;
> +
> +	if (count > 1) {
> +		pr_err("%s: only one event processing method can be defined (%s)\n",
> +		       __func__, handler->name);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
>  /**
>   * input_register_handler - register a new input handler
>   * @handler: handler to be registered
> @@ -2530,6 +2550,10 @@ int input_register_handler(struct input_handler *handler)
>  	struct input_dev *dev;
>  	int error;
>  
> +	error = input_handler_check_methods(handler);
> +	if (error)
> +		return error;
> +
>  	error = mutex_lock_interruptible(&input_mutex);
>  	if (error)
>  		return error;
> -- 
> 2.45.2.803.g4e1b14247a-goog
> 

Kind regards,
Jeff LaBundy
diff mbox series

Patch

diff --git a/drivers/input/input.c b/drivers/input/input.c
index fd4997ba263c..7e4f8824f4fd 100644
--- a/drivers/input/input.c
+++ b/drivers/input/input.c
@@ -2517,6 +2517,26 @@  void input_unregister_device(struct input_dev *dev)
 }
 EXPORT_SYMBOL(input_unregister_device);
 
+static int input_handler_check_methods(const struct input_handler *handler)
+{
+	int count = 0;
+
+	if (handler->filter)
+		count++;
+	if (handler->events)
+		count++;
+	if (handler->event)
+		count++;
+
+	if (count > 1) {
+		pr_err("%s: only one event processing method can be defined (%s)\n",
+		       __func__, handler->name);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 /**
  * input_register_handler - register a new input handler
  * @handler: handler to be registered
@@ -2530,6 +2550,10 @@  int input_register_handler(struct input_handler *handler)
 	struct input_dev *dev;
 	int error;
 
+	error = input_handler_check_methods(handler);
+	if (error)
+		return error;
+
 	error = mutex_lock_interruptible(&input_mutex);
 	if (error)
 		return error;