HID: Asus X205TA keyboard driver

Asus X205TA built-in keyboard contains wrong
logical maximum value in report descriptor.

0x05, 0x01, // Usage Page (Generic Desktop)
0x09, 0x06, // Usage (Keyboard)
0xa1, 0x01, // Collection (Application)
0x85, 0x01, // Report ID (1)
0x05, 0x07, // Usage Page (Keyboard/Keypad)
0x19, 0xe0, // Usage Minimum (224)
0x29, 0xe7, // Usage Maximum (231)
0x15, 0x00, // Logical Minimum (0)
0x25, 0x01, // Logical Maximum (1)
0x75, 0x01, // Report Size (1)
0x95, 0x08, // Report Count (8)
0x81, 0x02, // Input (Data,Array,Abs)
0x95, 0x01, // Report Count (1)
0x75, 0x08, // Report Size (8)
0x81, 0x03, // Input (Const,Var,Abs)
0x95, 0x05, // Report Count (5)
0x75, 0x01, // Report Size (1)
0x05, 0x08, // Usage (LED)
0x19, 0x01, // Usage Minimum (1)
0x29, 0x05, // Usage Maximum (5)
0x91, 0x02, // Output (Data,Var,Abs)
0x95, 0x01, // Report Count (1)
0x75, 0x03, // Report Size (3)
0x91, 0x03, // Output (Const,Var,Abs)
0x95, 0x06, // Report Count (6)
0x75, 0x08, // Report Size (8)
0x15, 0x00, // Logical Minimum (0)
0x25, 0x65, // Logical Maximum (101) * too small *
0x05, 0x07, // Usage Page (Keyboard/Keypad)
0x19, 0x00, // Usage Minimum (0)
0x29, 0xdd, // Usage Maximum (221)
0x81, 0x00, // Input(Data,Array,Abs)

In Asus X205TA japanese keyboard model,there are language
specific keys over usage id 101.
This patch correct wrong logical maximum in report
descriptor.

Signed-off-by: Yusuke Fujimaki <[e-mail]>
Signed-off-by: Jiri Kosina <[e-mail]>

drivers/hid/Kconfig

···
 
 	Say Y here if you want support for Apple infrared remote control.
 
+config HID_ASUS
+	tristate "Asus"
+	depends on I2C_HID
+	---help---
+	Support for Asus X205TA built-in keyboard via i2c.
+
 config HID_AUREAL
 	tristate "Aureal"
 	depends on HID

drivers/hid/Makefile

···
 obj-$(CONFIG_HID_ACRUX)		+= hid-axff.o
 obj-$(CONFIG_HID_APPLE)		+= hid-apple.o
 obj-$(CONFIG_HID_APPLEIR)	+= hid-appleir.o
+obj-$(CONFIG_HID_ASUS)		+= hid-asus.o
 obj-$(CONFIG_HID_AUREAL)	+= hid-aureal.o
 obj-$(CONFIG_HID_BELKIN)	+= hid-belkin.o
 obj-$(CONFIG_HID_BETOP_FF)	+= hid-betopff.o

drivers/hid/hid-asus.c

···
+/*
+ *  HID driver for Asus X205TA built-in keyboard.
+ *  Fixes small logical maximum to match usage maximum.
+ *
+ *  Copyright (c) 2016 Yusuke Fujimaki <[e-mail]>
+ *
+ *  This module based on hid-ortek by
+ *  Copyright (c) 2010 Johnathon Harris <[e-mail]>
+ *  Copyright (c) 2011 Jiri Kosina
+ */
+
+/*
+ * 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 "hid-ids.h"
+
+static __u8 *asus_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+		unsigned int *rsize)
+{
+	if (*rsize >= 180 && rdesc[54] == 0x25 && rdesc[55] == 0x65) {
+		hid_info(hdev, "Fixing up Asus X205TA report descriptor\n");
+		rdesc[55] = 0xdd;
+	}
+	return rdesc;
+}
+
+static const struct hid_device_id asus_devices[] = {
+	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_X205TA_KEYBOARD) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, asus_devices);
+
+static struct hid_driver asus_driver = {
+	.name = "asus",
+	.id_table = asus_devices,
+	.report_fixup = asus_report_fixup
+};
+module_hid_driver(asus_driver);
+
+MODULE_LICENSE("GPL");

drivers/hid/hid-core.c

···
 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_ALU_WIRELESS_2011_JIS) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_FOUNTAIN_TP_ONLY) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_GEYSER1_TP_ONLY) },
+	{ HID_I2C_DEVICE(USB_VENDOR_ID_ASUSTEK, USB_DEVICE_ID_ASUSTEK_X205TA_KEYBOARD) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_AUREAL, USB_DEVICE_ID_AUREAL_W01RN) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_BELKIN, USB_DEVICE_ID_FLIP_KVM) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_BETOP_2185BFM, 0x2208) },

drivers/hid/hid-ids.h

···
 #define USB_VENDOR_ID_ASUSTEK		0x0b05
 #define USB_DEVICE_ID_ASUSTEK_LCM	0x1726
 #define USB_DEVICE_ID_ASUSTEK_LCM2	0x175b
+#define USB_DEVICE_ID_ASUSTEK_X205TA_KEYBOARD  0x8585
 
 #define USB_VENDOR_ID_ATEN		0x0557
 #define USB_DEVICE_ID_ATEN_UC100KM	0x2004