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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux
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#include <linux/export.h>#include <linux/input.h>#include <linux/input/mt.h>#include <linux/input/touch-overlay.h>#include <linux/list.h>#include <linux/module.h>#include <linux/property.h>
struct touch_overlay_segment { struct list_head list; u32 x_origin; u32 y_origin; u32 x_size; u32 y_size; u32 key; bool pressed; int slot;};
static int touch_overlay_get_segment(struct fwnode_handle *segment_node, struct touch_overlay_segment *segment, struct input_dev *input){ int error;
error = fwnode_property_read_u32(segment_node, "x-origin", &segment->x_origin); if (error) return error;
error = fwnode_property_read_u32(segment_node, "y-origin", &segment->y_origin); if (error) return error;
error = fwnode_property_read_u32(segment_node, "x-size", &segment->x_size); if (error) return error;
error = fwnode_property_read_u32(segment_node, "y-size", &segment->y_size); if (error) return error;
error = fwnode_property_read_u32(segment_node, "linux,code", &segment->key); if (!error) input_set_capability(input, EV_KEY, segment->key); else if (error != -EINVAL) return error;
return 0;}
/** * touch_overlay_map - map overlay objects from the device tree and set * key capabilities if buttons are defined. * @list: pointer to the list that will hold the segments * @input: pointer to the already allocated input_dev * * Returns 0 on success and error number otherwise. * * If buttons are defined, key capabilities are set accordingly. */int touch_overlay_map(struct list_head *list, struct input_dev *input){ struct fwnode_handle *fw_segment; struct device *dev = input->dev.parent; struct touch_overlay_segment *segment; int error;
struct fwnode_handle *overlay __free(fwnode_handle) = device_get_named_child_node(dev, "touch-overlay"); if (!overlay) return 0;
fwnode_for_each_available_child_node(overlay, fw_segment) { segment = devm_kzalloc(dev, sizeof(*segment), GFP_KERNEL); if (!segment) { fwnode_handle_put(fw_segment); return -ENOMEM; } error = touch_overlay_get_segment(fw_segment, segment, input); if (error) { fwnode_handle_put(fw_segment); return error; } list_add_tail(&segment->list, list); }
return 0;}EXPORT_SYMBOL(touch_overlay_map);
/** * touch_overlay_get_touchscreen_abs - get abs size from the touchscreen area. * @list: pointer to the list that holds the segments * @x: horizontal abs * @y: vertical abs */void touch_overlay_get_touchscreen_abs(struct list_head *list, u16 *x, u16 *y){ struct touch_overlay_segment *segment; struct list_head *ptr;
list_for_each(ptr, list) { segment = list_entry(ptr, struct touch_overlay_segment, list); if (!segment->key) { *x = segment->x_size - 1; *y = segment->y_size - 1; break; } }}EXPORT_SYMBOL(touch_overlay_get_touchscreen_abs);
static bool touch_overlay_segment_event(struct touch_overlay_segment *seg, struct input_mt_pos *pos){ if (pos->x >= seg->x_origin && pos->x < (seg->x_origin + seg->x_size) && pos->y >= seg->y_origin && pos->y < (seg->y_origin + seg->y_size)) return true;
return false;}
/** * touch_overlay_mapped_touchscreen - check if a touchscreen area is mapped * @list: pointer to the list that holds the segments * * Returns true if a touchscreen area is mapped or false otherwise. */bool touch_overlay_mapped_touchscreen(struct list_head *list){ struct touch_overlay_segment *segment; struct list_head *ptr;
list_for_each(ptr, list) { segment = list_entry(ptr, struct touch_overlay_segment, list); if (!segment->key) return true; }
return false;}EXPORT_SYMBOL(touch_overlay_mapped_touchscreen);
static bool touch_overlay_event_on_ts(struct list_head *list, struct input_mt_pos *pos){ struct touch_overlay_segment *segment; struct list_head *ptr;
list_for_each(ptr, list) { segment = list_entry(ptr, struct touch_overlay_segment, list); if (segment->key) continue;
if (touch_overlay_segment_event(segment, pos)) { pos->x -= segment->x_origin; pos->y -= segment->y_origin; return true; } /* ignore touch events outside the defined area */ return false; }
return true;}
static bool touch_overlay_button_event(struct input_dev *input, struct touch_overlay_segment *segment, struct input_mt_pos *pos, int slot){ struct input_mt *mt = input->mt; struct input_mt_slot *s = &mt->slots[slot]; bool button_contact = touch_overlay_segment_event(segment, pos);
if (segment->slot == slot && segment->pressed) { /* sliding out of the button releases it */ if (!button_contact) { input_report_key(input, segment->key, false); segment->pressed = false; /* keep available for a possible touch event */ return false; } /* ignore sliding on the button while pressed */ s->frame = mt->frame; return true; } else if (button_contact) { input_report_key(input, segment->key, true); s->frame = mt->frame; segment->slot = slot; segment->pressed = true; return true; }
return false;}
/** * touch_overlay_sync_frame - update the status of the segments and report * buttons whose tracked slot is unused. * @list: pointer to the list that holds the segments * @input: pointer to the input device associated to the contact */void touch_overlay_sync_frame(struct list_head *list, struct input_dev *input){ struct touch_overlay_segment *segment; struct input_mt *mt = input->mt; struct input_mt_slot *s; struct list_head *ptr;
list_for_each(ptr, list) { segment = list_entry(ptr, struct touch_overlay_segment, list); if (!segment->key) continue;
s = &mt->slots[segment->slot]; if (!input_mt_is_used(mt, s) && segment->pressed) { input_report_key(input, segment->key, false); segment->pressed = false; } }}EXPORT_SYMBOL(touch_overlay_sync_frame);
/** * touch_overlay_process_contact - process contacts according to the overlay * mapping. This function acts as a filter to release the calling driver * from the contacts that are either related to overlay buttons or out of the * overlay touchscreen area, if defined. * @list: pointer to the list that holds the segments * @input: pointer to the input device associated to the contact * @pos: pointer to the contact position * @slot: slot associated to the contact (0 if multitouch is not supported) * * Returns true if the contact was processed (reported for valid key events * and dropped for contacts outside the overlay touchscreen area) or false * if the contact must be processed by the caller. In that case this function * shifts the (x,y) coordinates to the overlay touchscreen axis if required. */bool touch_overlay_process_contact(struct list_head *list, struct input_dev *input, struct input_mt_pos *pos, int slot){ struct touch_overlay_segment *segment; struct list_head *ptr;
/* * buttons must be prioritized over overlay touchscreens to account for * overlappings e.g. a button inside the touchscreen area. */ list_for_each(ptr, list) { segment = list_entry(ptr, struct touch_overlay_segment, list); if (segment->key && touch_overlay_button_event(input, segment, pos, slot)) return true; }
/* * valid contacts on the overlay touchscreen are left for the client * to be processed/reported according to its (possibly) unique features. */ return !touch_overlay_event_on_ts(list, pos);}EXPORT_SYMBOL(touch_overlay_process_contact);
MODULE_LICENSE("GPL");MODULE_DESCRIPTION("Helper functions for overlay objects on touch devices");