diff options
| -rw-r--r-- | drivers/input/input.c | 36 | ||||
| -rw-r--r-- | include/linux/input.h | 2 |
2 files changed, 38 insertions, 0 deletions
diff --git a/drivers/input/input.c b/drivers/input/input.c index 3a5156012fb8..4456e82d370b 100644 --- a/drivers/input/input.c +++ b/drivers/input/input.c @@ -526,6 +526,42 @@ void input_set_abs_params(struct input_dev *dev, unsigned int axis, } EXPORT_SYMBOL(input_set_abs_params); +/** + * input_copy_abs - Copy absinfo from one input_dev to another + * @dst: Destination input device to copy the abs settings to + * @dst_axis: ABS_* value selecting the destination axis + * @src: Source input device to copy the abs settings from + * @src_axis: ABS_* value selecting the source axis + * + * Set absinfo for the selected destination axis by copying it from + * the specified source input device's source axis. + * This is useful to e.g. setup a pen/stylus input-device for combined + * touchscreen/pen hardware where the pen uses the same coordinates as + * the touchscreen. + */ +void input_copy_abs(struct input_dev *dst, unsigned int dst_axis, + const struct input_dev *src, unsigned int src_axis) +{ + /* src must have EV_ABS and src_axis set */ + if (WARN_ON(!(test_bit(EV_ABS, src->evbit) && + test_bit(src_axis, src->absbit)))) + return; + + /* + * input_alloc_absinfo() may have failed for the source. Our caller is + * expected to catch this when registering the input devices, which may + * happen after the input_copy_abs() call. + */ + if (!src->absinfo) + return; + + input_set_capability(dst, EV_ABS, dst_axis); + if (!dst->absinfo) + return; + + dst->absinfo[dst_axis] = src->absinfo[src_axis]; +} +EXPORT_SYMBOL(input_copy_abs); /** * input_grab_device - grabs device for exclusive use diff --git a/include/linux/input.h b/include/linux/input.h index 0354b298d874..49790c1bd2c4 100644 --- a/include/linux/input.h +++ b/include/linux/input.h @@ -475,6 +475,8 @@ static inline void input_set_events_per_packet(struct input_dev *dev, int n_even void input_alloc_absinfo(struct input_dev *dev); void input_set_abs_params(struct input_dev *dev, unsigned int axis, int min, int max, int fuzz, int flat); +void input_copy_abs(struct input_dev *dst, unsigned int dst_axis, + const struct input_dev *src, unsigned int src_axis); #define INPUT_GENERATE_ABS_ACCESSORS(_suffix, _item) \ static inline int input_abs_get_##_suffix(struct input_dev *dev, \ |