Re: [PATCH 2/3] HID: multitouch: use input_register callback

[Jiri Kosina]

On Tue, 29 Nov 2011, Benjamin Tissoires wrote:

> Use the input_register mechanism to avoid a race in which the device
> may emit events before the slots are ready.
> 
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxx>
> ---
>  drivers/hid/hid-multitouch.c |   37 ++++++++++++++++++++++++-------------
>  1 files changed, 24 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
> index 91c13bc..bd6e410 100644
> --- a/drivers/hid/hid-multitouch.c
> +++ b/drivers/hid/hid-multitouch.c
> @@ -574,6 +574,29 @@ static void mt_set_input_mode(struct hid_device *hdev)
>  	}
>  }
>  
> +static int mt_input_register(struct hid_device *hdev,
> +		struct hid_input *hidinput)
> +{
> +	int ret;
> +	struct mt_device *td = hid_get_drvdata(hdev);
> +
> +	td->slots = kzalloc(td->maxcontacts * sizeof(struct mt_slot),
> +				GFP_KERNEL);
> +	if (!td->slots) {
> +		dev_err(&hdev->dev, "cannot allocate multitouch slots\n");
> +		return -ENOMEM;
> +	}
> +
> +	ret = sysfs_create_group(&hdev->dev.kobj, &mt_attribute_group);
> +	if (ret)
> +		hid_warn(hdev,
> +			 "can't create sysfs quirks attribute err: %d\n", ret);
> +
> +	mt_set_input_mode(hdev);
> +
> +	return 0;
> +}
> +
>  static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
>  {
>  	int ret, i;
> @@ -610,19 +633,6 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
>  	if (ret)
>  		goto fail;
>  
> -	td->slots = kzalloc(td->maxcontacts * sizeof(struct mt_slot),
> -				GFP_KERNEL);
> -	if (!td->slots) {
> -		dev_err(&hdev->dev, "cannot allocate multitouch slots\n");
> -		hid_hw_stop(hdev);
> -		ret = -ENOMEM;
> -		goto fail;
> -	}
> -
> -	ret = sysfs_create_group(&hdev->dev.kobj, &mt_attribute_group);
> -
> -	mt_set_input_mode(hdev);
> -
>  	return 0;
>  
>  fail:
> @@ -843,6 +853,7 @@ static struct hid_driver mt_driver = {
>  	.input_mapping = mt_input_mapping,
>  	.input_mapped = mt_input_mapped,
>  	.feature_mapping = mt_feature_mapping,
> +	.input_register = mt_input_register,

Umm, where does this come from? My memory is famous for not being really 
excellent, but I don't immediately remember any patchset adding such 
callback to hid_driver struct.

And it's not anywhere in my applied queue anyway.

>  	.usage_table = mt_grabbed_usages,
>  	.event = mt_event,
>  #ifdef CONFIG_PM
> -- 
> 1.7.4.4
> 

-- 
Jiri Kosina
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/