// SPDX-License-Identifier: GPL-2.0-or-later /* * HID driver for Holtek keyboard * Copyright (c) 2012 Tom Harwood */ /* */ #include #include #include #include #include "hid-ids.h" #include "usbhid/usbhid.h" /* Holtek based keyboards (USB ID 04d9:a055) have the following issues: * - The report descriptor specifies an excessively large number of consumer * usages (2^15), which is more than HID_MAX_USAGES. This prevents proper * parsing of the report descriptor. * - The report descriptor reports on caps/scroll/num lock key presses, but * doesn't have an LED output usage block. * * The replacement descriptor below fixes the number of consumer usages, * and provides an LED output usage block. LED output events are redirected * to the boot interface. */ static const __u8 holtek_kbd_rdesc_fixed[] = { /* Original report descriptor, with reduced number of consumer usages */ 0x05, 0x01, /* Usage Page (Desktop), */ 0x09, 0x80, /* Usage (Sys Control), */ 0xA1, 0x01, /* Collection (Application), */ 0x85, 0x01, /* Report ID (1), */ 0x19, 0x81, /* Usage Minimum (Sys Power Down), */ 0x29, 0x83, /* Usage Maximum (Sys Wake Up), */ 0x15, 0x00, /* Logical Minimum (0), */ 0x25, 0x01, /* Logical Maximum (1), */ 0x95, 0x03, /* Report Count (3), */ 0x75, 0x01, /* Report Size (1), */ 0x81, 0x02, /* Input (Variable), */ 0x95, 0x01, /* Report Count (1), */ 0x75, 0x05, /* Report Size (5), */ 0x81, 0x01, /* Input (Constant), */ 0xC0, /* End Collection, */ 0x05, 0x0C, /* Usage Page (Consumer), */ 0x09, 0x01, /* Usage (Consumer Control), */ 0xA1, 0x01, /* Collection (Application), */ 0x85, 0x02, /* Report ID (2), */ 0x19, 0x00, /* Usage Minimum (00h), */ 0x2A, 0xFF, 0x2F, /* Usage Maximum (0x2FFF), previously 0x7FFF */ 0x15, 0x00, /* Logical Minimum (0), */ 0x26, 0xFF, 0x2F, /* Logical Maximum (0x2FFF),previously 0x7FFF*/ 0x95, 0x01, /* Report Count (1), */ 0x75, 0x10, /* Report Size (16), */ 0x81, 0x00, /* Input, */ 0xC0, /* End Collection, */ 0x05, 0x01, /* Usage Page (Desktop), */ 0x09, 0x06, /* Usage (Keyboard), */ 0xA1, 0x01, /* Collection (Application), */ 0x85, 0x03, /* Report ID (3), */ 0x95, 0x38, /* Report Count (56), */ 0x75, 0x01, /* Report Size (1), */ 0x15, 0x00, /* Logical Minimum (0), */ 0x25, 0x01, /* Logical Maximum (1), */ 0x05, 0x07, /* Usage Page (Keyboard), */ 0x19, 0xE0, /* Usage Minimum (KB Leftcontrol), */ 0x29, 0xE7, /* Usage Maximum (KB Right GUI), */ 0x19, 0x00, /* Usage Minimum (None), */ 0x29, 0x2F, /* Usage Maximum (KB Lboxbracket And Lbrace),*/ 0x81, 0x02, /* Input (Variable), */ 0xC0, /* End Collection, */ 0x05, 0x01, /* Usage Page (Desktop), */ 0x09, 0x06, /* Usage (Keyboard), */ 0xA1, 0x01, /* Collection (Application), */ 0x85, 0x04, /* Report ID (4), */ 0x95, 0x38, /* Report Count (56), */ 0x75, 0x01, /* Report Size (1), */ 0x15, 0x00, /* Logical Minimum (0), */ 0x25, 0x01, /* Logical Maximum (1), */ 0x05, 0x07, /* Usage Page (Keyboard), */ 0x19, 0x30, /* Usage Minimum (KB Rboxbracket And Rbrace),*/ 0x29, 0x67, /* Usage Maximum (KP Equals), */ 0x81, 0x02, /* Input (Variable), */ 0xC0, /* End Collection */ /* LED usage for the boot protocol interface */ 0x05, 0x01, /* Usage Page (Desktop), */ 0x09, 0x06, /* Usage (Keyboard), */ 0xA1, 0x01, /* Collection (Application), */ 0x05, 0x08, /* Usage Page (LED), */ 0x19, 0x01, /* Usage Minimum (01h), */ 0x29, 0x03, /* Usage Maximum (03h), */ 0x15, 0x00, /* Logical Minimum (0), */ 0x25, 0x01, /* Logical Maximum (1), */ 0x75, 0x01, /* Report Size (1), */ 0x95, 0x03, /* Report Count (3), */ 0x91, 0x02, /* Output (Variable), */ 0x95, 0x05, /* Report Count (5), */ 0x91, 0x01, /* Output (Constant), */ 0xC0, /* End Collection */ }; static const __u8 *holtek_kbd_report_fixup(struct hid_device *hdev, __u8 *rdesc, unsigned int *rsize) { struct usb_interface *intf = to_usb_interface(hdev->dev.parent); if (intf->cur_altsetting->desc.bInterfaceNumber == 1) { *rsize = sizeof(holtek_kbd_rdesc_fixed); return holtek_kbd_rdesc_fixed; } return rdesc; } static int holtek_kbd_input_event(struct input_dev *dev, unsigned int type, unsigned int code, int value) { struct hid_device *hid = input_get_drvdata(dev); struct usb_device *usb_dev = hid_to_usb_dev(hid); /* Locate the boot interface, to receive the LED change events */ struct usb_interface *boot_interface = usb_ifnum_to_if(usb_dev, 0); struct hid_device *boot_hid; struct hid_input *boot_hid_input; if (unlikely(boot_interface == NULL)) return -ENODEV; boot_hid = usb_get_intfdata(boot_interface); if (list_empty(&boot_hid->inputs)) { hid_err(hid, "no inputs found\n"); return -ENODEV; } boot_hid_input = list_first_entry(&boot_hid->inputs, struct hid_input, list); return boot_hid_input->input->event(boot_hid_input->input, type, code, value); } static int holtek_kbd_probe(struct hid_device *hdev, const struct hid_device_id *id) { struct usb_interface *intf; int ret; if (!hid_is_usb(hdev)) return -EINVAL; ret = hid_parse(hdev); if (!ret) ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); intf = to_usb_interface(hdev->dev.parent); if (!ret && intf->cur_altsetting->desc.bInterfaceNumber == 1) { struct hid_input *hidinput; list_for_each_entry(hidinput, &hdev->inputs, list) { hidinput->input->event = holtek_kbd_input_event; } } return ret; } static const struct hid_device_id holtek_kbd_devices[] = { { HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK_ALT, USB_DEVICE_ID_HOLTEK_ALT_KEYBOARD) }, { } }; MODULE_DEVICE_TABLE(hid, holtek_kbd_devices); static struct hid_driver holtek_kbd_driver = { .name = "holtek_kbd", .id_table = holtek_kbd_devices, .report_fixup = holtek_kbd_report_fixup, .probe = holtek_kbd_probe }; module_hid_driver(holtek_kbd_driver); MODULE_DESCRIPTION("HID driver for Holtek keyboard"); MODULE_LICENSE("GPL");