75 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			75 lines
		
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
 | |
| /*
 | |
|  * HID driver for primax and similar keyboards with in-band modifiers
 | |
|  *
 | |
|  * Copyright 2011 Google Inc. All Rights Reserved
 | |
|  *
 | |
|  * Author:
 | |
|  *	Terry Lambert <tlambert@google.com>
 | |
|  */
 | |
| 
 | |
| #include <linux/device.h>
 | |
| #include <linux/hid.h>
 | |
| #include <linux/module.h>
 | |
| 
 | |
| #include "hid-ids.h"
 | |
| 
 | |
| static int px_raw_event(struct hid_device *hid, struct hid_report *report,
 | |
| 	 u8 *data, int size)
 | |
| {
 | |
| 	int idx = size;
 | |
| 
 | |
| 	switch (report->id) {
 | |
| 	case 0:		/* keyboard input */
 | |
| 		/*
 | |
| 		 * Convert in-band modifier key values into out of band
 | |
| 		 * modifier bits and pull the key strokes from the report.
 | |
| 		 * Thus a report data set which looked like:
 | |
| 		 *
 | |
| 		 * [00][00][E0][30][00][00][00][00]
 | |
| 		 * (no modifier bits + "Left Shift" key + "1" key)
 | |
| 		 *
 | |
| 		 * Would be converted to:
 | |
| 		 *
 | |
| 		 * [01][00][00][30][00][00][00][00]
 | |
| 		 * (Left Shift modifier bit + "1" key)
 | |
| 		 *
 | |
| 		 * As long as it's in the size range, the upper level
 | |
| 		 * drivers don't particularly care if there are in-band
 | |
| 		 * 0-valued keys, so they don't stop parsing.
 | |
| 		 */
 | |
| 		while (--idx > 1) {
 | |
| 			if (data[idx] < 0xE0 || data[idx] > 0xE7)
 | |
| 				continue;
 | |
| 			data[0] |= (1 << (data[idx] - 0xE0));
 | |
| 			data[idx] = 0;
 | |
| 		}
 | |
| 		hid_report_raw_event(hid, HID_INPUT_REPORT, data, size, 0);
 | |
| 		return 1;
 | |
| 
 | |
| 	default:	/* unknown report */
 | |
| 		/* Unknown report type; pass upstream */
 | |
| 		hid_info(hid, "unknown report type %d\n", report->id);
 | |
| 		break;
 | |
| 	}
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| static const struct hid_device_id px_devices[] = {
 | |
| 	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_KEYBOARD) },
 | |
| 	{ }
 | |
| };
 | |
| MODULE_DEVICE_TABLE(hid, px_devices);
 | |
| 
 | |
| static struct hid_driver px_driver = {
 | |
| 	.name = "primax",
 | |
| 	.id_table = px_devices,
 | |
| 	.raw_event = px_raw_event,
 | |
| };
 | |
| module_hid_driver(px_driver);
 | |
| 
 | |
| MODULE_AUTHOR("Terry Lambert <tlambert@google.com>");
 | |
| MODULE_DESCRIPTION("HID driver for primax and similar keyboards with in-band modifiers");
 | |
| MODULE_LICENSE("GPL");
 |