| /* |
| * HID driver for Cando dual-touch panels |
| * |
| * Copyright (c) 2010 Stephane Chatty <chatty@enac.fr> |
| * |
| */ |
| |
| /* |
| * This program is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License as published by the Free |
| * Software Foundation; either version 2 of the License, or (at your option) |
| * any later version. |
| */ |
| |
| #include <linux/device.h> |
| #include <linux/hid.h> |
| #include <linux/module.h> |
| #include <linux/slab.h> |
| |
| MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>"); |
| MODULE_DESCRIPTION("Cando dual-touch panel"); |
| MODULE_LICENSE("GPL"); |
| |
| #include "hid-ids.h" |
| |
| struct cando_data { |
| __u16 x, y; |
| __u8 id; |
| __s8 oldest; /* id of the oldest finger in previous frame */ |
| bool valid; /* valid finger data, or just placeholder? */ |
| bool first; /* is this the first finger in this frame? */ |
| __s8 firstid; /* id of the first finger in the frame */ |
| __u16 firstx, firsty; /* (x, y) of the first finger in the frame */ |
| }; |
| |
| static int cando_input_mapping(struct hid_device *hdev, struct hid_input *hi, |
| struct hid_field *field, struct hid_usage *usage, |
| unsigned long **bit, int *max) |
| { |
| switch (usage->hid & HID_USAGE_PAGE) { |
| |
| case HID_UP_GENDESK: |
| switch (usage->hid) { |
| case HID_GD_X: |
| hid_map_usage(hi, usage, bit, max, |
| EV_ABS, ABS_MT_POSITION_X); |
| /* touchscreen emulation */ |
| input_set_abs_params(hi->input, ABS_X, |
| field->logical_minimum, |
| field->logical_maximum, 0, 0); |
| return 1; |
| case HID_GD_Y: |
| hid_map_usage(hi, usage, bit, max, |
| EV_ABS, ABS_MT_POSITION_Y); |
| /* touchscreen emulation */ |
| input_set_abs_params(hi->input, ABS_Y, |
| field->logical_minimum, |
| field->logical_maximum, 0, 0); |
| return 1; |
| } |
| return 0; |
| |
| case HID_UP_DIGITIZER: |
| switch (usage->hid) { |
| case HID_DG_TIPSWITCH: |
| case HID_DG_CONTACTMAX: |
| return -1; |
| case HID_DG_INRANGE: |
| /* touchscreen emulation */ |
| hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH); |
| return 1; |
| case HID_DG_CONTACTID: |
| hid_map_usage(hi, usage, bit, max, |
| EV_ABS, ABS_MT_TRACKING_ID); |
| return 1; |
| } |
| return 0; |
| } |
| |
| return 0; |
| } |
| |
| static int cando_input_mapped(struct hid_device *hdev, struct hid_input *hi, |
| struct hid_field *field, struct hid_usage *usage, |
| unsigned long **bit, int *max) |
| { |
| if (usage->type == EV_KEY || usage->type == EV_ABS) |
| clear_bit(usage->code, *bit); |
| |
| return 0; |
| } |
| |
| /* |
| * this function is called when a whole finger has been parsed, |
| * so that it can decide what to send to the input layer. |
| */ |
| static void cando_filter_event(struct cando_data *td, struct input_dev *input) |
| { |
| td->first = !td->first; /* touchscreen emulation */ |
| |
| if (!td->valid) { |
| /* |
| * touchscreen emulation: if this is the second finger and |
| * the first was valid, the first was the oldest; if the |
| * first was not valid and there was a valid finger in the |
| * previous frame, this is a release. |
| */ |
| if (td->first) { |
| td->firstid = -1; |
| } else if (td->firstid >= 0) { |
| input_event(input, EV_ABS, ABS_X, td->firstx); |
| input_event(input, EV_ABS, ABS_Y, td->firsty); |
| td->oldest = td->firstid; |
| } else if (td->oldest >= 0) { |
| input_event(input, EV_KEY, BTN_TOUCH, 0); |
| td->oldest = -1; |
| } |
| |
| return; |
| } |
| |
| input_event(input, EV_ABS, ABS_MT_TRACKING_ID, td->id); |
| input_event(input, EV_ABS, ABS_MT_POSITION_X, td->x); |
| input_event(input, EV_ABS, ABS_MT_POSITION_Y, td->y); |
| |
| input_mt_sync(input); |
| |
| /* |
| * touchscreen emulation: if there was no touching finger previously, |
| * emit touch event |
| */ |
| if (td->oldest < 0) { |
| input_event(input, EV_KEY, BTN_TOUCH, 1); |
| td->oldest = td->id; |
| } |
| |
| /* |
| * touchscreen emulation: if this is the first finger, wait for the |
| * second; the oldest is then the second if it was the oldest already |
| * or if there was no first, the first otherwise. |
| */ |
| if (td->first) { |
| td->firstx = td->x; |
| td->firsty = td->y; |
| td->firstid = td->id; |
| } else { |
| int x, y, oldest; |
| if (td->id == td->oldest || td->firstid < 0) { |
| x = td->x; |
| y = td->y; |
| oldest = td->id; |
| } else { |
| x = td->firstx; |
| y = td->firsty; |
| oldest = td->firstid; |
| } |
| input_event(input, EV_ABS, ABS_X, x); |
| input_event(input, EV_ABS, ABS_Y, y); |
| td->oldest = oldest; |
| } |
| } |
| |
| |
| static int cando_event(struct hid_device *hid, struct hid_field *field, |
| struct hid_usage *usage, __s32 value) |
| { |
| struct cando_data *td = hid_get_drvdata(hid); |
| |
| if (hid->claimed & HID_CLAIMED_INPUT) { |
| struct input_dev *input = field->hidinput->input; |
| |
| switch (usage->hid) { |
| case HID_DG_INRANGE: |
| td->valid = value; |
| break; |
| case HID_DG_CONTACTID: |
| td->id = value; |
| break; |
| case HID_GD_X: |
| td->x = value; |
| break; |
| case HID_GD_Y: |
| td->y = value; |
| cando_filter_event(td, input); |
| break; |
| case HID_DG_TIPSWITCH: |
| /* avoid interference from generic hidinput handling */ |
| break; |
| |
| default: |
| /* fallback to the generic hidinput handling */ |
| return 0; |
| } |
| } |
| |
| /* we have handled the hidinput part, now remains hiddev */ |
| if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event) |
| hid->hiddev_hid_event(hid, field, usage, value); |
| |
| return 1; |
| } |
| |
| static int cando_probe(struct hid_device *hdev, const struct hid_device_id *id) |
| { |
| int ret; |
| struct cando_data *td; |
| |
| td = kmalloc(sizeof(struct cando_data), GFP_KERNEL); |
| if (!td) { |
| dev_err(&hdev->dev, "cannot allocate Cando Touch data\n"); |
| return -ENOMEM; |
| } |
| hid_set_drvdata(hdev, td); |
| td->first = false; |
| td->oldest = -1; |
| td->valid = false; |
| |
| ret = hid_parse(hdev); |
| if (!ret) |
| ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); |
| |
| if (ret) |
| kfree(td); |
| |
| return ret; |
| } |
| |
| static void cando_remove(struct hid_device *hdev) |
| { |
| hid_hw_stop(hdev); |
| kfree(hid_get_drvdata(hdev)); |
| hid_set_drvdata(hdev, NULL); |
| } |
| |
| static const struct hid_device_id cando_devices[] = { |
| { HID_USB_DEVICE(USB_VENDOR_ID_CANDO, |
| USB_DEVICE_ID_CANDO_MULTI_TOUCH) }, |
| { HID_USB_DEVICE(USB_VENDOR_ID_CANDO, |
| USB_DEVICE_ID_CANDO_MULTI_TOUCH_11_6) }, |
| { HID_USB_DEVICE(USB_VENDOR_ID_CANDO, |
| USB_DEVICE_ID_CANDO_MULTI_TOUCH_15_6) }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(hid, cando_devices); |
| |
| static const struct hid_usage_id cando_grabbed_usages[] = { |
| { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID }, |
| { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1} |
| }; |
| |
| static struct hid_driver cando_driver = { |
| .name = "cando-touch", |
| .id_table = cando_devices, |
| .probe = cando_probe, |
| .remove = cando_remove, |
| .input_mapping = cando_input_mapping, |
| .input_mapped = cando_input_mapped, |
| .usage_table = cando_grabbed_usages, |
| .event = cando_event, |
| }; |
| |
| static int __init cando_init(void) |
| { |
| return hid_register_driver(&cando_driver); |
| } |
| |
| static void __exit cando_exit(void) |
| { |
| hid_unregister_driver(&cando_driver); |
| } |
| |
| module_init(cando_init); |
| module_exit(cando_exit); |
| |