1 /* 2 * HID driver for primax and similar keyboards with in-band modifiers 3 * 4 * Copyright 2011 Google Inc. All Rights Reserved 5 * 6 * Author: 7 * Terry Lambert <tlambert@google.com> 8 * 9 * This software is licensed under the terms of the GNU General Public 10 * License version 2, as published by the Free Software Foundation, and 11 * may be copied, distributed, and modified under those terms. 12 * 13 * This program is distributed in the hope that it will be useful, 14 * but WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 * GNU General Public License for more details. 17 */ 18 19 #include <linux/device.h> 20 #include <linux/hid.h> 21 #include <linux/module.h> 22 23 #include "hid-ids.h" 24 25 static int px_raw_event(struct hid_device *hid, struct hid_report *report, 26 u8 *data, int size) 27 { 28 int idx = size; 29 30 switch (report->id) { 31 case 0: /* keyboard input */ 32 /* 33 * Convert in-band modifier key values into out of band 34 * modifier bits and pull the key strokes from the report. 35 * Thus a report data set which looked like: 36 * 37 * [00][00][E0][30][00][00][00][00] 38 * (no modifier bits + "Left Shift" key + "1" key) 39 * 40 * Would be converted to: 41 * 42 * [01][00][00][30][00][00][00][00] 43 * (Left Shift modifier bit + "1" key) 44 * 45 * As long as it's in the size range, the upper level 46 * drivers don't particularly care if there are in-band 47 * 0-valued keys, so they don't stop parsing. 48 */ 49 while (--idx > 1) { 50 if (data[idx] < 0xE0 || data[idx] > 0xE7) 51 continue; 52 data[0] |= (1 << (data[idx] - 0xE0)); 53 data[idx] = 0; 54 } 55 hid_report_raw_event(hid, HID_INPUT_REPORT, data, size, 0); 56 return 1; 57 58 default: /* unknown report */ 59 /* Unknown report type; pass upstream */ 60 hid_info(hid, "unknown report type %d\n", report->id); 61 break; 62 } 63 64 return 0; 65 } 66 67 static const struct hid_device_id px_devices[] = { 68 { HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_KEYBOARD) }, 69 { } 70 }; 71 MODULE_DEVICE_TABLE(hid, px_devices); 72 73 static struct hid_driver px_driver = { 74 .name = "primax", 75 .id_table = px_devices, 76 .raw_event = px_raw_event, 77 }; 78 module_hid_driver(px_driver); 79 80 MODULE_AUTHOR("Terry Lambert <tlambert@google.com>"); 81 MODULE_LICENSE("GPL"); 82