HID: apple: Add support for keyboard backlight on certain T2 Macs.

This patch introduces the requisite plumbing for supporting keyboard
backlight on T2-attached, USB exposed models. The quirk mechanism was
used to reuse the existing hid-apple driver.

Signed-off-by: Paul Pawlowski <paul@mrarm.io>
Signed-off-by: Aun-Ali Zaidi <admin@kodeit.net>
Signed-off-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
Paul Pawlowski 2022-02-03 12:21:13 +00:00 committed by Jiri Kosina
parent cbfcfbfc38
commit 9018eacbe6

View File

@ -7,6 +7,7 @@
* Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
* Copyright (c) 2006-2007 Jiri Kosina
* Copyright (c) 2008 Jiri Slaby <jirislaby@gmail.com>
* Copyright (c) 2019 Paul Pawlowski <paul@mrarm.io>
*/
/*
@ -33,6 +34,7 @@
/* BIT(7) reserved, was: APPLE_IGNORE_HIDINPUT */
#define APPLE_NUMLOCK_EMULATION BIT(8)
#define APPLE_RDESC_BATTERY BIT(9)
#define APPLE_BACKLIGHT_CTL BIT(10)
#define APPLE_FLAG_FKEY 0x01
@ -61,6 +63,12 @@ MODULE_PARM_DESC(swap_fn_leftctrl, "Swap the Fn and left Control keys. "
"(For people who want to keep PC keyboard muscle memory. "
"[0] = as-is, Mac layout, 1 = swapped, PC layout)");
struct apple_sc_backlight {
struct led_classdev cdev;
struct hid_device *hdev;
unsigned short backlight_off, backlight_on_min, backlight_on_max;
};
struct apple_sc {
struct hid_device *hdev;
unsigned long quirks;
@ -68,6 +76,7 @@ struct apple_sc {
unsigned int fn_found;
DECLARE_BITMAP(pressed_numlock, KEY_CNT);
struct timer_list battery_timer;
struct apple_sc_backlight *backlight;
};
struct apple_key_translation {
@ -117,6 +126,20 @@ static const struct apple_key_translation magic_keyboard_2015_fn_keys[] = {
{ }
};
struct apple_backlight_config_report {
u8 report_id;
u8 version;
u16 backlight_off, backlight_on_min, backlight_on_max;
};
struct apple_backlight_set_report {
u8 report_id;
u8 version;
u16 backlight;
u16 rate;
};
static const struct apple_key_translation apple2021_fn_keys[] = {
{ KEY_BACKSPACE, KEY_DELETE },
{ KEY_ENTER, KEY_INSERT },
@ -582,6 +605,105 @@ static int apple_input_configured(struct hid_device *hdev,
return 0;
}
static bool apple_backlight_check_support(struct hid_device *hdev)
{
int i;
unsigned int hid;
struct hid_report *report;
list_for_each_entry(report, &hdev->report_enum[HID_INPUT_REPORT].report_list, list) {
for (i = 0; i < report->maxfield; i++) {
hid = report->field[i]->usage->hid;
if ((hid & HID_USAGE_PAGE) == HID_UP_MSVENDOR && (hid & HID_USAGE) == 0xf)
return true;
}
}
return false;
}
static int apple_backlight_set(struct hid_device *hdev, u16 value, u16 rate)
{
int ret = 0;
struct apple_backlight_set_report *rep;
rep = kmalloc(sizeof(*rep), GFP_KERNEL);
if (rep == NULL)
return -ENOMEM;
rep->report_id = 0xB0;
rep->version = 1;
rep->backlight = value;
rep->rate = rate;
ret = hid_hw_raw_request(hdev, 0xB0u, (u8 *) rep, sizeof(*rep),
HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
kfree(rep);
return ret;
}
static int apple_backlight_led_set(struct led_classdev *led_cdev,
enum led_brightness brightness)
{
struct apple_sc_backlight *backlight = container_of(led_cdev,
struct apple_sc_backlight, cdev);
return apple_backlight_set(backlight->hdev, brightness, 0);
}
static int apple_backlight_init(struct hid_device *hdev)
{
int ret;
struct apple_sc *asc = hid_get_drvdata(hdev);
struct apple_backlight_config_report *rep;
if (!apple_backlight_check_support(hdev))
return -EINVAL;
rep = kmalloc(0x200, GFP_KERNEL);
if (rep == NULL)
return -ENOMEM;
ret = hid_hw_raw_request(hdev, 0xBFu, (u8 *) rep, sizeof(*rep),
HID_FEATURE_REPORT, HID_REQ_GET_REPORT);
if (ret < 0) {
hid_err(hdev, "backlight request failed: %d\n", ret);
goto cleanup_and_exit;
}
if (ret < 8 || rep->version != 1) {
hid_err(hdev, "backlight config struct: bad version %i\n", rep->version);
ret = -EINVAL;
goto cleanup_and_exit;
}
hid_dbg(hdev, "backlight config: off=%u, on_min=%u, on_max=%u\n",
rep->backlight_off, rep->backlight_on_min, rep->backlight_on_max);
asc->backlight = devm_kzalloc(&hdev->dev, sizeof(*asc->backlight), GFP_KERNEL);
if (!asc->backlight) {
ret = -ENOMEM;
goto cleanup_and_exit;
}
asc->backlight->hdev = hdev;
asc->backlight->cdev.name = "apple::kbd_backlight";
asc->backlight->cdev.max_brightness = rep->backlight_on_max;
asc->backlight->cdev.brightness_set_blocking = apple_backlight_led_set;
ret = apple_backlight_set(hdev, 0, 0);
if (ret < 0) {
hid_err(hdev, "backlight set request failed: %d\n", ret);
goto cleanup_and_exit;
}
ret = devm_led_classdev_register(&hdev->dev, &asc->backlight->cdev);
cleanup_and_exit:
kfree(rep);
return ret;
}
static int apple_probe(struct hid_device *hdev,
const struct hid_device_id *id)
{
@ -617,6 +739,9 @@ static int apple_probe(struct hid_device *hdev,
jiffies + msecs_to_jiffies(APPLE_BATTERY_TIMEOUT_MS));
apple_fetch_battery(hdev);
if (quirks & APPLE_BACKLIGHT_CTL)
apple_backlight_init(hdev);
return 0;
}