2018-03-14 19:28:25 -06:00
|
|
|
// SPDX-License-Identifier: GPL-2.0+
|
|
|
|
/*
|
|
|
|
* HID driver for Google Hammer device.
|
|
|
|
*
|
|
|
|
* Copyright (c) 2017 Google Inc.
|
|
|
|
* Author: Wei-Ning Huang <wnhuang@google.com>
|
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
|
|
|
* 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/hid.h>
|
|
|
|
#include <linux/leds.h>
|
|
|
|
#include <linux/module.h>
|
|
|
|
|
|
|
|
#include "hid-ids.h"
|
|
|
|
|
|
|
|
#define MAX_BRIGHTNESS 100
|
|
|
|
|
|
|
|
/* HID usage for keyboard backlight (Alphanumeric display brightness) */
|
|
|
|
#define HID_AD_BRIGHTNESS 0x00140046
|
|
|
|
|
|
|
|
struct hammer_kbd_leds {
|
|
|
|
struct led_classdev cdev;
|
|
|
|
struct hid_device *hdev;
|
|
|
|
u8 buf[2] ____cacheline_aligned;
|
|
|
|
};
|
|
|
|
|
|
|
|
static int hammer_kbd_brightness_set_blocking(struct led_classdev *cdev,
|
|
|
|
enum led_brightness br)
|
|
|
|
{
|
|
|
|
struct hammer_kbd_leds *led = container_of(cdev,
|
|
|
|
struct hammer_kbd_leds,
|
|
|
|
cdev);
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
led->buf[0] = 0;
|
|
|
|
led->buf[1] = br;
|
|
|
|
|
2018-03-28 00:16:10 -06:00
|
|
|
/*
|
|
|
|
* Request USB HID device to be in Full On mode, so that sending
|
|
|
|
* hardware output report and hardware raw request won't fail.
|
|
|
|
*/
|
|
|
|
ret = hid_hw_power(led->hdev, PM_HINT_FULLON);
|
|
|
|
if (ret < 0) {
|
|
|
|
hid_err(led->hdev, "failed: device not resumed %d\n", ret);
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
2018-03-14 19:28:25 -06:00
|
|
|
ret = hid_hw_output_report(led->hdev, led->buf, sizeof(led->buf));
|
|
|
|
if (ret == -ENOSYS)
|
|
|
|
ret = hid_hw_raw_request(led->hdev, 0, led->buf,
|
|
|
|
sizeof(led->buf),
|
|
|
|
HID_OUTPUT_REPORT,
|
|
|
|
HID_REQ_SET_REPORT);
|
|
|
|
if (ret < 0)
|
|
|
|
hid_err(led->hdev, "failed to set keyboard backlight: %d\n",
|
|
|
|
ret);
|
2018-03-28 00:16:10 -06:00
|
|
|
|
|
|
|
/* Request USB HID device back to Normal Mode. */
|
|
|
|
hid_hw_power(led->hdev, PM_HINT_NORMAL);
|
|
|
|
|
2018-03-14 19:28:25 -06:00
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int hammer_register_leds(struct hid_device *hdev)
|
|
|
|
{
|
|
|
|
struct hammer_kbd_leds *kbd_backlight;
|
|
|
|
|
|
|
|
kbd_backlight = devm_kzalloc(&hdev->dev,
|
|
|
|
sizeof(*kbd_backlight),
|
|
|
|
GFP_KERNEL);
|
|
|
|
if (!kbd_backlight)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
kbd_backlight->hdev = hdev;
|
|
|
|
kbd_backlight->cdev.name = "hammer::kbd_backlight";
|
|
|
|
kbd_backlight->cdev.max_brightness = MAX_BRIGHTNESS;
|
|
|
|
kbd_backlight->cdev.brightness_set_blocking =
|
|
|
|
hammer_kbd_brightness_set_blocking;
|
|
|
|
kbd_backlight->cdev.flags = LED_HW_PLUGGABLE;
|
|
|
|
|
|
|
|
/* Set backlight to 0% initially. */
|
|
|
|
hammer_kbd_brightness_set_blocking(&kbd_backlight->cdev, 0);
|
|
|
|
|
|
|
|
return devm_led_classdev_register(&hdev->dev, &kbd_backlight->cdev);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int hammer_input_configured(struct hid_device *hdev,
|
|
|
|
struct hid_input *hi)
|
|
|
|
{
|
|
|
|
struct list_head *report_list =
|
|
|
|
&hdev->report_enum[HID_OUTPUT_REPORT].report_list;
|
|
|
|
struct hid_report *report;
|
|
|
|
|
|
|
|
if (list_empty(report_list))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
report = list_first_entry(report_list, struct hid_report, list);
|
|
|
|
|
|
|
|
if (report->maxfield == 1 &&
|
|
|
|
report->field[0]->application == HID_GD_KEYBOARD &&
|
|
|
|
report->field[0]->maxusage == 1 &&
|
|
|
|
report->field[0]->usage[0].hid == HID_AD_BRIGHTNESS) {
|
|
|
|
int err = hammer_register_leds(hdev);
|
|
|
|
|
|
|
|
if (err)
|
|
|
|
hid_warn(hdev,
|
|
|
|
"Failed to register keyboard backlight: %d\n",
|
|
|
|
err);
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct hid_device_id hammer_devices[] = {
|
|
|
|
{ HID_DEVICE(BUS_USB, HID_GROUP_GENERIC,
|
|
|
|
USB_VENDOR_ID_GOOGLE, USB_DEVICE_ID_GOOGLE_HAMMER) },
|
|
|
|
{ HID_DEVICE(BUS_USB, HID_GROUP_GENERIC,
|
|
|
|
USB_VENDOR_ID_GOOGLE, USB_DEVICE_ID_GOOGLE_STAFF) },
|
|
|
|
{ HID_DEVICE(BUS_USB, HID_GROUP_GENERIC,
|
|
|
|
USB_VENDOR_ID_GOOGLE, USB_DEVICE_ID_GOOGLE_WAND) },
|
|
|
|
{ }
|
|
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(hid, hammer_devices);
|
|
|
|
|
|
|
|
static struct hid_driver hammer_driver = {
|
|
|
|
.name = "hammer",
|
|
|
|
.id_table = hammer_devices,
|
|
|
|
.input_configured = hammer_input_configured,
|
|
|
|
};
|
|
|
|
module_hid_driver(hammer_driver);
|
|
|
|
|
|
|
|
MODULE_LICENSE("GPL");
|