On Jul 03 2024, Aditya Garg wrote:
> From: Orlando Chamberlain <orlandoch.dev@xxxxxxxxx>
>
> Unlike T2 Macs with Butterfly keyboard, who have their keyboard backlight
> on the USB device the T2 Macs with Magic keyboard have their backlight on
> the Touchbar backlight device (05ac:8102).
>
> Support for Butterfly keyboards has already been added in 9018eacbe623
> ("HID: apple: Add support for keyboard backlight on certain T2 Macs.").
> This patch adds support for the Magic keyboards.
>
> Co-developed-by: Aditya Garg <gargaditya08@xxxxxxxx>
> Signed-off-by: Aditya Garg <gargaditya08@xxxxxxxx>
> Signed-off-by: Orlando Chamberlain <orlandoch.dev@xxxxxxxxx>
Nitpick: the ordering of the signed-off is weird. It should be in order
of persons who touched this driver.
Given that the From is Orlando and Aditya is submitting, I would have
expected Orlando, then Aditya...
> ---
> drivers/hid/hid-apple.c | 87 ++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 86 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hid/hid-apple.c b/drivers/hid/hid-apple.c
> index bd022e004356..2d1cd4456303 100644
> --- a/drivers/hid/hid-apple.c
> +++ b/drivers/hid/hid-apple.c
> @@ -8,6 +8,8 @@
> * Copyright (c) 2006-2007 Jiri Kosina
> * Copyright (c) 2008 Jiri Slaby <jirislaby@xxxxxxxxx>
> * Copyright (c) 2019 Paul Pawlowski <paul@xxxxxxxx>
> + * Copyright (c) 2023 Orlando Chamberlain <orlandoch.dev@xxxxxxxxx>
> + * Copyright (c) 2024 Aditya Garg <gargaditya08@xxxxxxxx>
> */
>
> /*
> @@ -23,6 +25,7 @@
> #include <linux/timer.h>
> #include <linux/string.h>
> #include <linux/leds.h>
> +#include <dt-bindings/leds/common.h>
>
> #include "hid-ids.h"
>
> @@ -37,13 +40,18 @@
> #define APPLE_NUMLOCK_EMULATION BIT(8)
> #define APPLE_RDESC_BATTERY BIT(9)
> #define APPLE_BACKLIGHT_CTL BIT(10)
> -#define APPLE_IS_NON_APPLE BIT(11)
> +#define APPLE_MAGIC_BACKLIGHT BIT(11)
> +#define APPLE_IS_NON_APPLE BIT(12)
Please keep existing quirks definition in place, it adds noise for
nothing in the patch. Also, technically, these quirks are used in
.driver_data so they are uapi.
>
> #define APPLE_FLAG_FKEY 0x01
>
> #define HID_COUNTRY_INTERNATIONAL_ISO 13
> #define APPLE_BATTERY_TIMEOUT_MS 60000
>
> +#define HID_USAGE_MAGIC_BL 0xff00000f
> +#define APPLE_MAGIC_REPORT_ID_POWER 3
> +#define APPLE_MAGIC_REPORT_ID_BRIGHTNESS 1
> +
> static unsigned int fnmode = 3;
> module_param(fnmode, uint, 0644);
> MODULE_PARM_DESC(fnmode, "Mode of fn key on Apple keyboards (0 = disabled, "
> @@ -81,6 +89,12 @@ struct apple_sc_backlight {
> struct hid_device *hdev;
> };
>
> +struct apple_magic_backlight {
> + struct led_classdev cdev;
> + struct hid_report *brightness;
> + struct hid_report *power;
> +};
> +
> struct apple_sc {
> struct hid_device *hdev;
> unsigned long quirks;
> @@ -822,6 +836,66 @@ static int apple_backlight_init(struct hid_device *hdev)
> return ret;
> }
>
> +static void apple_magic_backlight_report_set(struct hid_report *rep, s32 value, u8 rate)
> +{
> + rep->field[0]->value[0] = value;
> + rep->field[1]->value[0] = 0x5e; /* Mimic Windows */
> + rep->field[1]->value[0] |= rate << 8;
> +
> + hid_hw_request(rep->device, rep, HID_REQ_SET_REPORT);
> +}
> +
> +static void apple_magic_backlight_set(struct apple_magic_backlight *backlight,
> + int brightness, char rate)
> +{
> + apple_magic_backlight_report_set(backlight->power, brightness ? 1 : 0, rate);
> + if (brightness)
> + apple_magic_backlight_report_set(backlight->brightness, brightness, rate);
> +}
> +
> +static int apple_magic_backlight_led_set(struct led_classdev *led_cdev,
> + enum led_brightness brightness)
> +{
> + struct apple_magic_backlight *backlight = container_of(led_cdev,
> + struct apple_magic_backlight, cdev);
> +
> + apple_magic_backlight_set(backlight, brightness, 1);
> + return 0;
> +}
> +
> +static int apple_magic_backlight_init(struct hid_device *hdev)
> +{
> + struct apple_magic_backlight *backlight;
> +
> + /*
> + * Ensure this usb endpoint is for the keyboard backlight, not touchbar
> + * backlight.
> + */
> + if (hdev->collection[0].usage != HID_USAGE_MAGIC_BL)
> + return -ENODEV;
> +
> + backlight = devm_kzalloc(&hdev->dev, sizeof(*backlight), GFP_KERNEL);
> + if (!backlight)
> + return -ENOMEM;
> +
> + backlight->brightness = hid_register_report(hdev, HID_FEATURE_REPORT,
> + APPLE_MAGIC_REPORT_ID_BRIGHTNESS, 0);
> + backlight->power = hid_register_report(hdev, HID_FEATURE_REPORT,
> + APPLE_MAGIC_REPORT_ID_POWER, 0);
> +
> + if (!backlight->brightness || !backlight->power)
> + return -ENODEV;
> +
> + backlight->cdev.name = ":white:" LED_FUNCTION_KBD_BACKLIGHT;
> + backlight->cdev.max_brightness = backlight->brightness->field[0]->logical_maximum;
This is weird: a few lines above, you register a new report with
hid_register_report() and now you are directly accessing
field[0]->logical_maximum in that new report, which should be set to 0.
Unless you are using hid_register_report() to retrieve an existing
report, which is bending the API a bit but is OK, but you should at
least check that report->size is > 0 (and put a comment that the reports
exist already).
(or do what is done in apple_fetch_battery() to retrieve the current
report)
> + backlight->cdev.brightness_set_blocking = apple_magic_backlight_led_set;
> +
> + apple_magic_backlight_set(backlight, 0, 0);
> +
> + return devm_led_classdev_register(&hdev->dev, &backlight->cdev);
> +
> +}
> +
> static int apple_probe(struct hid_device *hdev,
> const struct hid_device_id *id)
> {
> @@ -860,6 +934,15 @@ static int apple_probe(struct hid_device *hdev,
> if (quirks & APPLE_BACKLIGHT_CTL)
> apple_backlight_init(hdev);
>
> + if (quirks & APPLE_MAGIC_BACKLIGHT) {
> + ret = apple_magic_backlight_init(hdev);
> + if (ret) {
> + del_timer_sync(&asc->battery_timer);
> + hid_hw_stop(hdev);
> + return ret;
Instead of manually unwind the probe in each sub-quirk, please add a new
goto label and do goto out_err;
> + }
> + }
> +
> return 0;
> }
>
> @@ -1073,6 +1156,8 @@ static const struct hid_device_id apple_devices[] = {
> .driver_data = APPLE_HAS_FN | APPLE_ISO_TILDE_QUIRK | APPLE_RDESC_BATTERY },
> { HID_BLUETOOTH_DEVICE(BT_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGIC_KEYBOARD_NUMPAD_2021),
> .driver_data = APPLE_HAS_FN | APPLE_ISO_TILDE_QUIRK },
> + { HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_TOUCHBAR_BACKLIGHT),
> + .driver_data = APPLE_MAGIC_BACKLIGHT },
>
> { }
> };
> --
> 2.45.2
>
Other than those few nitpicks, patch looks good. Please roll a v3 and
I'll apply it.
Cheers,
Benjamin
