1 /* 2 * HID driver for Holtek keyboard 3 * Copyright (c) 2012 Tom Harwood 4 */ 5 6 /* 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the Free 9 * Software Foundation; either version 2 of the License, or (at your option) 10 * any later version. 11 */ 12 13 #include <linux/device.h> 14 #include <linux/hid.h> 15 #include <linux/module.h> 16 #include <linux/usb.h> 17 18 #include "hid-ids.h" 19 #include "usbhid/usbhid.h" 20 21 /* Holtek based keyboards (USB ID 04d9:a055) have the following issues: 22 * - The report descriptor specifies an excessively large number of consumer 23 * usages (2^15), which is more than HID_MAX_USAGES. This prevents proper 24 * parsing of the report descriptor. 25 * - The report descriptor reports on caps/scroll/num lock key presses, but 26 * doesn't have an LED output usage block. 27 * 28 * The replacement descriptor below fixes the number of consumer usages, 29 * and provides an LED output usage block. LED output events are redirected 30 * to the boot interface. 31 */ 32 33 static __u8 holtek_kbd_rdesc_fixed[] = { 34 /* Original report descriptor, with reduced number of consumer usages */ 35 0x05, 0x01, /* Usage Page (Desktop), */ 36 0x09, 0x80, /* Usage (Sys Control), */ 37 0xA1, 0x01, /* Collection (Application), */ 38 0x85, 0x01, /* Report ID (1), */ 39 0x19, 0x81, /* Usage Minimum (Sys Power Down), */ 40 0x29, 0x83, /* Usage Maximum (Sys Wake Up), */ 41 0x15, 0x00, /* Logical Minimum (0), */ 42 0x25, 0x01, /* Logical Maximum (1), */ 43 0x95, 0x03, /* Report Count (3), */ 44 0x75, 0x01, /* Report Size (1), */ 45 0x81, 0x02, /* Input (Variable), */ 46 0x95, 0x01, /* Report Count (1), */ 47 0x75, 0x05, /* Report Size (5), */ 48 0x81, 0x01, /* Input (Constant), */ 49 0xC0, /* End Collection, */ 50 0x05, 0x0C, /* Usage Page (Consumer), */ 51 0x09, 0x01, /* Usage (Consumer Control), */ 52 0xA1, 0x01, /* Collection (Application), */ 53 0x85, 0x02, /* Report ID (2), */ 54 0x19, 0x00, /* Usage Minimum (00h), */ 55 0x2A, 0xFF, 0x2F, /* Usage Maximum (0x2FFF), previously 0x7FFF */ 56 0x15, 0x00, /* Logical Minimum (0), */ 57 0x26, 0xFF, 0x2F, /* Logical Maximum (0x2FFF),previously 0x7FFF*/ 58 0x95, 0x01, /* Report Count (1), */ 59 0x75, 0x10, /* Report Size (16), */ 60 0x81, 0x00, /* Input, */ 61 0xC0, /* End Collection, */ 62 0x05, 0x01, /* Usage Page (Desktop), */ 63 0x09, 0x06, /* Usage (Keyboard), */ 64 0xA1, 0x01, /* Collection (Application), */ 65 0x85, 0x03, /* Report ID (3), */ 66 0x95, 0x38, /* Report Count (56), */ 67 0x75, 0x01, /* Report Size (1), */ 68 0x15, 0x00, /* Logical Minimum (0), */ 69 0x25, 0x01, /* Logical Maximum (1), */ 70 0x05, 0x07, /* Usage Page (Keyboard), */ 71 0x19, 0xE0, /* Usage Minimum (KB Leftcontrol), */ 72 0x29, 0xE7, /* Usage Maximum (KB Right GUI), */ 73 0x19, 0x00, /* Usage Minimum (None), */ 74 0x29, 0x2F, /* Usage Maximum (KB Lboxbracket And Lbrace),*/ 75 0x81, 0x02, /* Input (Variable), */ 76 0xC0, /* End Collection, */ 77 0x05, 0x01, /* Usage Page (Desktop), */ 78 0x09, 0x06, /* Usage (Keyboard), */ 79 0xA1, 0x01, /* Collection (Application), */ 80 0x85, 0x04, /* Report ID (4), */ 81 0x95, 0x38, /* Report Count (56), */ 82 0x75, 0x01, /* Report Size (1), */ 83 0x15, 0x00, /* Logical Minimum (0), */ 84 0x25, 0x01, /* Logical Maximum (1), */ 85 0x05, 0x07, /* Usage Page (Keyboard), */ 86 0x19, 0x30, /* Usage Minimum (KB Rboxbracket And Rbrace),*/ 87 0x29, 0x67, /* Usage Maximum (KP Equals), */ 88 0x81, 0x02, /* Input (Variable), */ 89 0xC0, /* End Collection */ 90 91 /* LED usage for the boot protocol interface */ 92 0x05, 0x01, /* Usage Page (Desktop), */ 93 0x09, 0x06, /* Usage (Keyboard), */ 94 0xA1, 0x01, /* Collection (Application), */ 95 0x05, 0x08, /* Usage Page (LED), */ 96 0x19, 0x01, /* Usage Minimum (01h), */ 97 0x29, 0x03, /* Usage Maximum (03h), */ 98 0x15, 0x00, /* Logical Minimum (0), */ 99 0x25, 0x01, /* Logical Maximum (1), */ 100 0x75, 0x01, /* Report Size (1), */ 101 0x95, 0x03, /* Report Count (3), */ 102 0x91, 0x02, /* Output (Variable), */ 103 0x95, 0x05, /* Report Count (5), */ 104 0x91, 0x01, /* Output (Constant), */ 105 0xC0, /* End Collection */ 106 }; 107 108 static __u8 *holtek_kbd_report_fixup(struct hid_device *hdev, __u8 *rdesc, 109 unsigned int *rsize) 110 { 111 struct usb_interface *intf = to_usb_interface(hdev->dev.parent); 112 113 if (intf->cur_altsetting->desc.bInterfaceNumber == 1) { 114 rdesc = holtek_kbd_rdesc_fixed; 115 *rsize = sizeof(holtek_kbd_rdesc_fixed); 116 } 117 return rdesc; 118 } 119 120 static int holtek_kbd_input_event(struct input_dev *dev, unsigned int type, 121 unsigned int code, 122 int value) 123 { 124 struct hid_device *hid = input_get_drvdata(dev); 125 struct usb_device *usb_dev = hid_to_usb_dev(hid); 126 127 /* Locate the boot interface, to receive the LED change events */ 128 struct usb_interface *boot_interface = usb_ifnum_to_if(usb_dev, 0); 129 130 struct hid_device *boot_hid = usb_get_intfdata(boot_interface); 131 struct hid_input *boot_hid_input = list_first_entry(&boot_hid->inputs, 132 struct hid_input, list); 133 134 return boot_hid_input->input->event(boot_hid_input->input, type, code, 135 value); 136 } 137 138 static int holtek_kbd_probe(struct hid_device *hdev, 139 const struct hid_device_id *id) 140 { 141 struct usb_interface *intf = to_usb_interface(hdev->dev.parent); 142 int ret = hid_parse(hdev); 143 144 if (!ret) 145 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); 146 147 if (!ret && intf->cur_altsetting->desc.bInterfaceNumber == 1) { 148 struct hid_input *hidinput; 149 list_for_each_entry(hidinput, &hdev->inputs, list) { 150 hidinput->input->event = holtek_kbd_input_event; 151 } 152 } 153 154 return ret; 155 } 156 157 static const struct hid_device_id holtek_kbd_devices[] = { 158 { HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK_ALT, 159 USB_DEVICE_ID_HOLTEK_ALT_KEYBOARD) }, 160 { } 161 }; 162 MODULE_DEVICE_TABLE(hid, holtek_kbd_devices); 163 164 static struct hid_driver holtek_kbd_driver = { 165 .name = "holtek_kbd", 166 .id_table = holtek_kbd_devices, 167 .report_fixup = holtek_kbd_report_fixup, 168 .probe = holtek_kbd_probe 169 }; 170 module_hid_driver(holtek_kbd_driver); 171 172 MODULE_LICENSE("GPL"); 173