Re: [PATCH 2/2] HID: ite: Add hid-ite driver

[Benjamin Tissoires <benjamin.tissoires@redhat.com>]

On May 10 2017 or thereabouts, Hans de Goede wrote:
> The ITE8595 keyboard uses the HID_GD_RFKILL_BTN usage code
> from the Wireless Radio Controls Application Collection Microsoft
> has defined for Windows 8 and later.
> 
> However it has a quirk, when the rfkill hotkey is pressed it does
> generate a report for the collection, but the reported value is
> always 0. Luckily it is the only button in this collection / report,
> and it sends a report on release only, so receiving a report means the
> button was pressed.
> 
> This commit adds a hid-ite driver which watches for the Wireless Radio
> Controls Application Collection report and then reports a KEY_RFKILL event,
> ignoring the value, making the rfkill on this keyboard work.
> 
> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
> ---
>  drivers/hid/Kconfig    |  7 +++++++
>  drivers/hid/Makefile   |  1 +
>  drivers/hid/hid-core.c |  1 +
>  drivers/hid/hid-ids.h  |  1 +
>  drivers/hid/hid-ite.c  | 56 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  5 files changed, 66 insertions(+)
>  create mode 100644 drivers/hid/hid-ite.c
> 
> diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> index 8c54cb8f5d6d..8db13f2b748b 100644
> --- a/drivers/hid/Kconfig
> +++ b/drivers/hid/Kconfig
> @@ -370,6 +370,13 @@ config HID_ICADE
>  	To compile this driver as a module, choose M here: the
>  	module will be called hid-icade.
>  
> +config HID_ITE
> +	tristate "ITE devices"
> +	depends on HID
> +	default !EXPERT
> +	---help---
> +	Support for ITE devices not fully compliant with HID standard.
> +
>  config HID_TWINHAN
>  	tristate "Twinhan IR remote control"
>  	depends on HID
> diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> index 4d111f23e801..606545745cfe 100644
> --- a/drivers/hid/Makefile
> +++ b/drivers/hid/Makefile
> @@ -49,6 +49,7 @@ obj-$(CONFIG_HID_HOLTEK)	+= hid-holtek-mouse.o
>  obj-$(CONFIG_HID_HOLTEK)	+= hid-holtekff.o
>  obj-$(CONFIG_HID_HYPERV_MOUSE)	+= hid-hyperv.o
>  obj-$(CONFIG_HID_ICADE)		+= hid-icade.o
> +obj-$(CONFIG_HID_ITE)		+= hid-ite.o
>  obj-$(CONFIG_HID_KENSINGTON)	+= hid-kensington.o
>  obj-$(CONFIG_HID_KEYTOUCH)	+= hid-keytouch.o
>  obj-$(CONFIG_HID_KYE)		+= hid-kye.o
> diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
> index 63ec1993eaaa..9348a6f589f7 100644
> --- a/drivers/hid/hid-core.c
> +++ b/drivers/hid/hid-core.c
> @@ -1911,6 +1911,7 @@ static const struct hid_device_id hid_have_special_driver[] = {
>  	{ HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK_ALT, USB_DEVICE_ID_HOLTEK_ALT_MOUSE_A081) },
>  	{ HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK_ALT, USB_DEVICE_ID_HOLTEK_ALT_MOUSE_A0C2) },
>  	{ HID_USB_DEVICE(USB_VENDOR_ID_HUION, USB_DEVICE_ID_HUION_TABLET) },
> +	{ HID_USB_DEVICE(USB_VENDOR_ID_ITE, USB_DEVICE_ID_ITE8595) },
>  	{ HID_USB_DEVICE(USB_VENDOR_ID_JESS, USB_DEVICE_ID_JESS_ZEN_AIO_KBD) },
>  	{ HID_USB_DEVICE(USB_VENDOR_ID_JESS2, USB_DEVICE_ID_JESS2_COLOR_RUMBLE_PAD) },
>  	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_ION, USB_DEVICE_ID_ICADE) },
> diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
> index 4e2648c86c8c..975c82993308 100644
> --- a/drivers/hid/hid-ids.h
> +++ b/drivers/hid/hid-ids.h
> @@ -552,6 +552,7 @@
>  #define USB_DEVICE_ID_ITE_LENOVO_YOGA   0x8386
>  #define USB_DEVICE_ID_ITE_LENOVO_YOGA2  0x8350
>  #define USB_DEVICE_ID_ITE_LENOVO_YOGA900	0x8396
> +#define USB_DEVICE_ID_ITE8595		0x8595
>  
>  #define USB_VENDOR_ID_JABRA		0x0b0e
>  #define USB_DEVICE_ID_JABRA_SPEAK_410	0x0412
> diff --git a/drivers/hid/hid-ite.c b/drivers/hid/hid-ite.c
> new file mode 100644
> index 000000000000..1882a4ab0f29
> --- /dev/null
> +++ b/drivers/hid/hid-ite.c
> @@ -0,0 +1,56 @@
> +/*
> + * HID driver for some ITE "special" devices
> + * Copyright (c) 2017 Hans de Goede <hdegoede@redhat.com>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/input.h>
> +#include <linux/hid.h>
> +#include <linux/module.h>
> +
> +#include "hid-ids.h"
> +
> +static int ite_event(struct hid_device *hdev, struct hid_field *field,
> +		     struct hid_usage *usage, __s32 value)
> +{
> +	struct input_dev *input;
> +
> +	if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput)

I would say if HID_CLAIMED_INPUT is there, there is no reasons for
field->hidinput to not be set.

> +		return 0;
> +
> +	input = field->hidinput->input;
> +
> +	/*
> +	 * The ITE8595 always reports 0 as value for the rfkill button. Luckily
> +	 * it is the only button in its report, and it sends a report on
> +	 * release only, so receiving a report means the button was pressed.
> +	 */
> +	if (usage->hid == HID_GD_RFKILL_BTN) {
> +		input_event(input, EV_KEY, KEY_RFKILL, 1);
> +		input_sync(input);
> +		input_event(input, EV_KEY, KEY_RFKILL, 0);
> +		input_sync(input);
> +		return 1;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct hid_device_id ite_devices[] = {
> +	{ HID_USB_DEVICE(USB_VENDOR_ID_ITE, USB_DEVICE_ID_ITE8595) },
> +	{ }
> +};
> +MODULE_DEVICE_TABLE(hid, ite_devices);
> +
> +static struct hid_driver ite_driver = {
> +	.name = "itetech",
> +	.id_table = ite_devices,
> +	.event = ite_event,
> +};
> +module_hid_driver(ite_driver);
> +
> +MODULE_LICENSE("GPL");
> -- 
> 2.12.2
>

Cheers,
Benjamin