Re: [PATCH 6/7] HID: multitouch: append " Pen" to the name of the stylus input

["Henrik Rydberg" <rydberg@euromail.se>]

Hi Benjamin,

> This is not just cosmetics, it can help to write udev and X.org
> rules.
> 
> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
> ---
>  drivers/hid/hid-multitouch.c | 24 +++++++++++++++++++++++-
>  1 file changed, 23 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/hid/hid-multitouch.c b/drivers/hid/hid-multitouch.c
> index d89f0eb..faeec95 100644
> --- a/drivers/hid/hid-multitouch.c
> +++ b/drivers/hid/hid-multitouch.c
> @@ -44,6 +44,7 @@
>  #include <linux/slab.h>
>  #include <linux/usb.h>
>  #include <linux/input/mt.h>
> +#include <linux/string.h>
>  
>  
>  MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
> @@ -371,6 +372,15 @@ static int mt_pen_input_mapping(struct hid_device *hdev, struct hid_input *hi,
>  		unsigned long **bit, int *max)
>  {
>  	struct mt_device *td = hid_get_drvdata(hdev);
> +	char *name;
> +
> +	if (hi->input->name == hdev->name) {
> +		name = kzalloc(sizeof(hdev->name) + 5, GFP_KERNEL);
> +		if (name) {
> +			sprintf(name, "%s Pen", hdev->name);
> +			hi->input->name = name;
> +		}
> +	}

Why not simply duplicate the the string? This kind of magic sharing is
not really helping.  Also, for multi input devices, the assumptions in
hidinput_allocate() seem to be the culprit. Perhaps the fix should be
there instead.

>  
>  	td->pen_report_id = field->report->id;
>  
> @@ -914,6 +924,7 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
>  	int ret, i;
>  	struct mt_device *td;
>  	struct mt_class *mtclass = mt_classes; /* MT_CLS_DEFAULT */
> +	struct hid_input *hi;
>  
>  	for (i = 0; mt_classes[i].name ; i++) {
>  		if (id->driver_data == mt_classes[i].name) {
> @@ -964,7 +975,7 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
>  
>  	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
>  	if (ret)
> -		goto fail;
> +		goto hid_fail;
>  
>  	ret = sysfs_create_group(&hdev->dev.kobj, &mt_attribute_group);
>  
> @@ -976,6 +987,10 @@ static int mt_probe(struct hid_device *hdev, const struct hid_device_id *id)
>  
>  	return 0;
>  
> +hid_fail:
> +	list_for_each_entry(hi, &hdev->inputs, list)
> +		if (hi->input->name != hdev->name)
> +			kfree(hi->input->name);
>  fail:
>  	kfree(td->fields);
>  	kfree(td);
> @@ -1020,8 +1035,15 @@ static int mt_resume(struct hid_device *hdev)
>  static void mt_remove(struct hid_device *hdev)
>  {
>  	struct mt_device *td = hid_get_drvdata(hdev);
> +	struct hid_input *hi;
> +
>  	sysfs_remove_group(&hdev->dev.kobj, &mt_attribute_group);
>  	hid_hw_stop(hdev);
> +
> +	list_for_each_entry(hi, &hdev->inputs, list)
> +		if (hi->input->name != hdev->name)
> +			kfree(hi->input->name);
> +
>  	kfree(td);
>  	hid_set_drvdata(hdev, NULL);
>  }
> -- 
> 1.8.1.2
> 

Thanks,
Henrik