2023-02-16 04:15:50

by Orlando Chamberlain

[permalink] [raw]
Subject: [PATCHv2 0/2] Apple Magic Keyboard Backlight

This patchseries adds support for the internal keyboard backlight of
Macs with Apple's "Magic" keyboard (MacBookPro16,* and MacBookAir9,1),
and also documents what names should be used for keyboard backlight
leds in Documentation/leds/well-known-leds.txt.

A previous version of this patch was sent alongside some other drivers
here[1] but for v2 I'm submitting it separately to make upstreaming
easier.

v1->v2:
- drop unneeded remove function
- combine set functions
- add missing header inclusions
- avoid char as argument in favour of u8
- handful of style/formatting fixes
- use standard led name ":white:kbd_backlight"
- rename USAGE_MAGIC_BL to HID_USAGE_MAGIC_BL
- New patch documenting preferred keyboard backlight names

[1]: https://lore.kernel.org/linux-input/[email protected]/

Orlando Chamberlain (2):
Documentation: leds: standardise keyboard backlight led names
HID: apple-magic-backlight: Add driver for keyboard backlight on
internal Magic Keyboards

Documentation/leds/well-known-leds.txt | 8 ++
MAINTAINERS | 6 ++
drivers/hid/Kconfig | 13 +++
drivers/hid/Makefile | 1 +
drivers/hid/apple-magic-backlight.c | 125 +++++++++++++++++++++++++
5 files changed, 153 insertions(+)
create mode 100644 drivers/hid/apple-magic-backlight.c

--
2.39.1



2023-02-16 04:16:41

by Orlando Chamberlain

[permalink] [raw]
Subject: [PATCH 1/2] Documentation: leds: standardise keyboard backlight led names

Advice use of either "input*:*:kbd_backlight" or ":*:kbd_backlight". We
don't want drivers using vendor or product name (e.g. "smc", "apple",
"asus") as this information is available from sysfs anyway, and it made the
folder names inconsistent.

Signed-off-by: Orlando Chamberlain <[email protected]>
---
Documentation/leds/well-known-leds.txt | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/Documentation/leds/well-known-leds.txt b/Documentation/leds/well-known-leds.txt
index 2160382c86be..4e5429fce4d8 100644
--- a/Documentation/leds/well-known-leds.txt
+++ b/Documentation/leds/well-known-leds.txt
@@ -44,6 +44,14 @@ Legacy: "lp5523:kb{1,2,3,4,5,6}" (Nokia N900)

Frontlight/backlight of main keyboard.

+Good: ":*:kbd_backlight"
+Good: "input*:*:kbd_backlight"
+Legacy: "*:*:kbd_backlight"
+
+Many drivers have the vendor or product name as the first field of the led name,
+this makes names inconsistent and is redundant as that information is already in
+sysfs.
+
Legacy: "button-backlight" (Motorola Droid 4)

Some phones have touch buttons below screen; it is different from main
--
2.39.1


2023-02-16 04:17:07

by Orlando Chamberlain

[permalink] [raw]
Subject: [PATCH 2/2] HID: apple-magic-backlight: Add driver for keyboard backlight on internal Magic Keyboards

This driver adds support for the keyboard backlight on Intel T2 Macs
with internal Magic Keyboards (MacBookPro16,x and MacBookAir9,1)

Signed-off-by: Orlando Chamberlain <[email protected]>
Co-developed-by: Kerem Karabay <[email protected]>
Signed-off-by: Kerem Karabay <[email protected]>
---
MAINTAINERS | 6 ++
drivers/hid/Kconfig | 13 +++
drivers/hid/Makefile | 1 +
drivers/hid/apple-magic-backlight.c | 125 ++++++++++++++++++++++++++++
4 files changed, 145 insertions(+)
create mode 100644 drivers/hid/apple-magic-backlight.c

diff --git a/MAINTAINERS b/MAINTAINERS
index fb1471cb5ed3..3319f0c3ed1e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9201,6 +9201,12 @@ F: include/linux/pm.h
F: include/linux/suspend.h
F: kernel/power/

+HID APPLE MAGIC BACKLIGHT DRIVER
+M: Orlando Chamberlain <[email protected]>
+L: [email protected]
+S: Maintained
+F: drivers/hid/apple-magic-backlight.c
+
HID CORE LAYER
M: Jiri Kosina <[email protected]>
M: Benjamin Tissoires <[email protected]>
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index e2a5d30c8895..f4702d32ce2f 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -130,6 +130,19 @@ config HID_APPLE
Say Y here if you want support for keyboards of Apple iBooks, PowerBooks,
MacBooks, MacBook Pros and Apple Aluminum.

+config HID_APPLE_MAGIC_BACKLIGHT
+ tristate "Apple Magic Keyboard Backlight"
+ depends on USB_HID
+ depends on LEDS_CLASS
+ depends on NEW_LEDS
+ help
+ Say Y here if you want support for the keyboard backlight on Macs with
+ the magic keyboard (MacBookPro16,x and MacBookAir9,1). Note that this
+ driver is not for external magic keyboards.
+
+ To compile this driver as a module, choose M here: the
+ module will be called apple-magic-backlight.
+
config HID_APPLEIR
tristate "Apple infrared receiver"
depends on (USB_HID)
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index e8014c1a2f8b..5cbfe85dd31b 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -26,6 +26,7 @@ obj-$(CONFIG_HID_ACCUTOUCH) += hid-accutouch.o
obj-$(CONFIG_HID_ALPS) += hid-alps.o
obj-$(CONFIG_HID_ACRUX) += hid-axff.o
obj-$(CONFIG_HID_APPLE) += hid-apple.o
+obj-$(CONFIG_HID_APPLE_MAGIC_BACKLIGHT) += apple-magic-backlight.o
obj-$(CONFIG_HID_APPLEIR) += hid-appleir.o
obj-$(CONFIG_HID_CREATIVE_SB0540) += hid-creative-sb0540.o
obj-$(CONFIG_HID_ASUS) += hid-asus.o
diff --git a/drivers/hid/apple-magic-backlight.c b/drivers/hid/apple-magic-backlight.c
new file mode 100644
index 000000000000..ed5bcf5bb599
--- /dev/null
+++ b/drivers/hid/apple-magic-backlight.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Apple Magic Keyboard Backlight Driver
+ *
+ * For Intel Macs with internal Magic Keyboard (MacBookPro16,1-4 and MacBookAir9,1)
+ *
+ * Copyright (c) 2022 Kerem Karabay <[email protected]>
+ * Copyright (c) 2023 Orlando Chamberlain <[email protected]>
+ */
+
+#include <linux/hid.h>
+#include <linux/usb.h>
+#include <linux/leds.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <dt-bindings/leds/common.h>
+
+#include "hid-ids.h"
+
+#define HID_USAGE_MAGIC_BL 0xff00000f
+
+#define APPLE_MAGIC_REPORT_ID_POWER 3
+#define APPLE_MAGIC_REPORT_ID_BRIGHTNESS 1
+
+struct apple_magic_backlight {
+ struct led_classdev cdev;
+ struct hid_device *hdev;
+ struct hid_report *brightness;
+ struct hid_report *power;
+};
+
+static void apple_magic_backlight_report_set(struct hid_report *rep, u16 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_probe(struct hid_device *hdev,
+ const struct hid_device_id *id)
+{
+ struct apple_magic_backlight *backlight;
+ int rc;
+
+ rc = hid_parse(hdev);
+ if (rc)
+ return rc;
+
+ /*
+ * Ensure this usb endpoint is for the keyboard backlight, not touchbar
+ * backlight.
+ */
+ if (!(hdev->collection && hdev->collection[0].usage == HID_USAGE_MAGIC_BL))
+ return -ENODEV;
+
+ backlight = devm_kzalloc(&hdev->dev, sizeof(*backlight), GFP_KERNEL);
+ if (!backlight)
+ return -ENOMEM;
+
+ hid_set_drvdata(hdev, backlight);
+
+ rc = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
+ if (rc)
+ return rc;
+
+ 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) {
+ rc = -ENODEV;
+ goto hw_stop;
+ }
+
+ backlight->hdev = hdev;
+ backlight->cdev.name = ":white:" LED_FUNCTION_KBD_BACKLIGHT;
+ backlight->cdev.max_brightness = backlight->brightness->field[0]->logical_maximum;
+ 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);
+
+hw_stop:
+ hid_hw_stop(hdev);
+ return rc;
+}
+
+static const struct hid_device_id apple_magic_backlight_hid_ids[] = {
+ { HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_TOUCHBAR_BACKLIGHT) },
+ { }
+};
+MODULE_DEVICE_TABLE(hid, apple_magic_backlight_hid_ids);
+
+static struct hid_driver apple_magic_backlight_hid_driver = {
+ .name = "apple-magic-backlight",
+ .id_table = apple_magic_backlight_hid_ids,
+ .probe = apple_magic_backlight_probe,
+};
+module_hid_driver(apple_magic_backlight_hid_driver);
+
+MODULE_DESCRIPTION("MacBook Magic Keyboard Backlight");
+MODULE_AUTHOR("Orlando Chamberlain <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.39.1


2023-02-16 05:41:19

by Thomas Weißschuh

[permalink] [raw]
Subject: Re: [PATCH 2/2] HID: apple-magic-backlight: Add driver for keyboard backlight on internal Magic Keyboards

On Thu, Feb 16, 2023 at 03:12:28PM +1100, Orlando Chamberlain wrote:
> This driver adds support for the keyboard backlight on Intel T2 Macs
> with internal Magic Keyboards (MacBookPro16,x and MacBookAir9,1)
>
> Signed-off-by: Orlando Chamberlain <[email protected]>
> Co-developed-by: Kerem Karabay <[email protected]>
> Signed-off-by: Kerem Karabay <[email protected]>

The last Signed-off-by should be yours.
See Documentation/process/submitting-patches.rst.

> ---
> MAINTAINERS | 6 ++
> drivers/hid/Kconfig | 13 +++
> drivers/hid/Makefile | 1 +
> drivers/hid/apple-magic-backlight.c | 125 ++++++++++++++++++++++++++++
> 4 files changed, 145 insertions(+)
> create mode 100644 drivers/hid/apple-magic-backlight.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index fb1471cb5ed3..3319f0c3ed1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9201,6 +9201,12 @@ F: include/linux/pm.h
> F: include/linux/suspend.h
> F: kernel/power/
>
> +HID APPLE MAGIC BACKLIGHT DRIVER
> +M: Orlando Chamberlain <[email protected]>
> +L: [email protected]
> +S: Maintained
> +F: drivers/hid/apple-magic-backlight.c
> +
> HID CORE LAYER
> M: Jiri Kosina <[email protected]>
> M: Benjamin Tissoires <[email protected]>
> diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> index e2a5d30c8895..f4702d32ce2f 100644
> --- a/drivers/hid/Kconfig
> +++ b/drivers/hid/Kconfig
> @@ -130,6 +130,19 @@ config HID_APPLE
> Say Y here if you want support for keyboards of Apple iBooks, PowerBooks,
> MacBooks, MacBook Pros and Apple Aluminum.
>
> +config HID_APPLE_MAGIC_BACKLIGHT
> + tristate "Apple Magic Keyboard Backlight"
> + depends on USB_HID
> + depends on LEDS_CLASS
> + depends on NEW_LEDS
> + help
> + Say Y here if you want support for the keyboard backlight on Macs with
> + the magic keyboard (MacBookPro16,x and MacBookAir9,1). Note that this
> + driver is not for external magic keyboards.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called apple-magic-backlight.
> +
> config HID_APPLEIR
> tristate "Apple infrared receiver"
> depends on (USB_HID)
> diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> index e8014c1a2f8b..5cbfe85dd31b 100644
> --- a/drivers/hid/Makefile
> +++ b/drivers/hid/Makefile
> @@ -26,6 +26,7 @@ obj-$(CONFIG_HID_ACCUTOUCH) += hid-accutouch.o
> obj-$(CONFIG_HID_ALPS) += hid-alps.o
> obj-$(CONFIG_HID_ACRUX) += hid-axff.o
> obj-$(CONFIG_HID_APPLE) += hid-apple.o
> +obj-$(CONFIG_HID_APPLE_MAGIC_BACKLIGHT) += apple-magic-backlight.o
> obj-$(CONFIG_HID_APPLEIR) += hid-appleir.o
> obj-$(CONFIG_HID_CREATIVE_SB0540) += hid-creative-sb0540.o
> obj-$(CONFIG_HID_ASUS) += hid-asus.o
> diff --git a/drivers/hid/apple-magic-backlight.c b/drivers/hid/apple-magic-backlight.c
> new file mode 100644
> index 000000000000..ed5bcf5bb599
> --- /dev/null
> +++ b/drivers/hid/apple-magic-backlight.c
> @@ -0,0 +1,125 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Apple Magic Keyboard Backlight Driver
> + *
> + * For Intel Macs with internal Magic Keyboard (MacBookPro16,1-4 and MacBookAir9,1)
> + *
> + * Copyright (c) 2022 Kerem Karabay <[email protected]>
> + * Copyright (c) 2023 Orlando Chamberlain <[email protected]>
> + */
> +
> +#include <linux/hid.h>
> +#include <linux/usb.h>

No need for linux/usb.h.

> +#include <linux/leds.h>
> +#include <linux/device.h>
> +#include <linux/errno.h>
> +#include <dt-bindings/leds/common.h>
> +
> +#include "hid-ids.h"
> +
> +#define HID_USAGE_MAGIC_BL 0xff00000f
> +
> +#define APPLE_MAGIC_REPORT_ID_POWER 3
> +#define APPLE_MAGIC_REPORT_ID_BRIGHTNESS 1
> +
> +struct apple_magic_backlight {
> + struct led_classdev cdev;
> + struct hid_device *hdev;
> + struct hid_report *brightness;
> + struct hid_report *power;
> +};
> +
> +static void apple_magic_backlight_report_set(struct hid_report *rep, u16 value, u8 rate)
> +{

Could "value" be a s32? "logical_maximum" from the field is a s32,
so there is no risk of truncation.

> + 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_probe(struct hid_device *hdev,
> + const struct hid_device_id *id)
> +{
> + struct apple_magic_backlight *backlight;
> + int rc;
> +
> + rc = hid_parse(hdev);
> + if (rc)
> + return rc;
> +
> + /*
> + * Ensure this usb endpoint is for the keyboard backlight, not touchbar
> + * backlight.
> + */
> + if (!(hdev->collection && hdev->collection[0].usage == HID_USAGE_MAGIC_BL))
> + return -ENODEV;

I don't think hdev->collection can ever be NULL.

Also personally I would prefer this:

!hdev->collection || hdev->collection[0].usage != HID_USAGE_MAGIC_BL

Like it is done with the reports below.

> +
> + backlight = devm_kzalloc(&hdev->dev, sizeof(*backlight), GFP_KERNEL);
> + if (!backlight)
> + return -ENOMEM;
> +
> + hid_set_drvdata(hdev, backlight);

Is this needed?

> +
> + rc = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
> + if (rc)
> + return rc;
> +
> + 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) {
> + rc = -ENODEV;
> + goto hw_stop;
> + }
> +
> + backlight->hdev = hdev;
> + backlight->cdev.name = ":white:" LED_FUNCTION_KBD_BACKLIGHT;

> + backlight->cdev.max_brightness = backlight->brightness->field[0]->logical_maximum;
> + 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);
> +
> +hw_stop:
> + hid_hw_stop(hdev);
> + return rc;
> +}
> +
> +static const struct hid_device_id apple_magic_backlight_hid_ids[] = {
> + { HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_TOUCHBAR_BACKLIGHT) },
> + { }
> +};
> +MODULE_DEVICE_TABLE(hid, apple_magic_backlight_hid_ids);
> +
> +static struct hid_driver apple_magic_backlight_hid_driver = {
> + .name = "apple-magic-backlight",
> + .id_table = apple_magic_backlight_hid_ids,
> + .probe = apple_magic_backlight_probe,
> +};
> +module_hid_driver(apple_magic_backlight_hid_driver);
> +
> +MODULE_DESCRIPTION("MacBook Magic Keyboard Backlight");
> +MODULE_AUTHOR("Orlando Chamberlain <[email protected]>");
> +MODULE_LICENSE("GPL");
> --
> 2.39.1
>

Note: Only your cover letter has the "v2" prefix.
Normally git format-patch should apply this properly to all patches when
using --reroll-count.

2023-02-16 05:58:56

by Orlando Chamberlain

[permalink] [raw]
Subject: Re: [PATCH 2/2] HID: apple-magic-backlight: Add driver for keyboard backlight on internal Magic Keyboards

On Thu, 16 Feb 2023 05:41:05 +0000
Thomas Weißschuh <[email protected]> wrote:

> On Thu, Feb 16, 2023 at 03:12:28PM +1100, Orlando Chamberlain wrote:
> > This driver adds support for the keyboard backlight on Intel T2 Macs
> > with internal Magic Keyboards (MacBookPro16,x and MacBookAir9,1)
> >
> > Signed-off-by: Orlando Chamberlain <[email protected]>
> > Co-developed-by: Kerem Karabay <[email protected]>
> > Signed-off-by: Kerem Karabay <[email protected]>
>
> The last Signed-off-by should be yours.
> See Documentation/process/submitting-patches.rst.

I'll reorder that in v3, thanks for pointing it out.
>
> > ---
> > MAINTAINERS | 6 ++
> > drivers/hid/Kconfig | 13 +++
> > drivers/hid/Makefile | 1 +
> > drivers/hid/apple-magic-backlight.c | 125
> > ++++++++++++++++++++++++++++ 4 files changed, 145 insertions(+)
> > create mode 100644 drivers/hid/apple-magic-backlight.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index fb1471cb5ed3..3319f0c3ed1e 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -9201,6 +9201,12 @@ F: include/linux/pm.h
> > F: include/linux/suspend.h
> > F: kernel/power/
> >
> > +HID APPLE MAGIC BACKLIGHT DRIVER
> > +M: Orlando Chamberlain <[email protected]>
> > +L: [email protected]
> > +S: Maintained
> > +F: drivers/hid/apple-magic-backlight.c
> > +
> > HID CORE LAYER
> > M: Jiri Kosina <[email protected]>
> > M: Benjamin Tissoires <[email protected]>
> > diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> > index e2a5d30c8895..f4702d32ce2f 100644
> > --- a/drivers/hid/Kconfig
> > +++ b/drivers/hid/Kconfig
> > @@ -130,6 +130,19 @@ config HID_APPLE
> > Say Y here if you want support for keyboards of
> > Apple iBooks, PowerBooks, MacBooks, MacBook Pros and Apple Aluminum.
> >
> > +config HID_APPLE_MAGIC_BACKLIGHT
> > + tristate "Apple Magic Keyboard Backlight"
> > + depends on USB_HID
> > + depends on LEDS_CLASS
> > + depends on NEW_LEDS
> > + help
> > + Say Y here if you want support for the keyboard backlight
> > on Macs with
> > + the magic keyboard (MacBookPro16,x and MacBookAir9,1).
> > Note that this
> > + driver is not for external magic keyboards.
> > +
> > + To compile this driver as a module, choose M here: the
> > + module will be called apple-magic-backlight.
> > +
> > config HID_APPLEIR
> > tristate "Apple infrared receiver"
> > depends on (USB_HID)
> > diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> > index e8014c1a2f8b..5cbfe85dd31b 100644
> > --- a/drivers/hid/Makefile
> > +++ b/drivers/hid/Makefile
> > @@ -26,6 +26,7 @@ obj-$(CONFIG_HID_ACCUTOUCH) +=
> > hid-accutouch.o obj-$(CONFIG_HID_ALPS) += hid-alps.o
> > obj-$(CONFIG_HID_ACRUX) += hid-axff.o
> > obj-$(CONFIG_HID_APPLE) += hid-apple.o
> > +obj-$(CONFIG_HID_APPLE_MAGIC_BACKLIGHT) +=
> > apple-magic-backlight.o obj-$(CONFIG_HID_APPLEIR) +=
> > hid-appleir.o obj-$(CONFIG_HID_CREATIVE_SB0540) +=
> > hid-creative-sb0540.o obj-$(CONFIG_HID_ASUS) +=
> > hid-asus.o diff --git a/drivers/hid/apple-magic-backlight.c
> > b/drivers/hid/apple-magic-backlight.c new file mode 100644
> > index 000000000000..ed5bcf5bb599
> > --- /dev/null
> > +++ b/drivers/hid/apple-magic-backlight.c
> > @@ -0,0 +1,125 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Apple Magic Keyboard Backlight Driver
> > + *
> > + * For Intel Macs with internal Magic Keyboard (MacBookPro16,1-4
> > and MacBookAir9,1)
> > + *
> > + * Copyright (c) 2022 Kerem Karabay <[email protected]>
> > + * Copyright (c) 2023 Orlando Chamberlain <[email protected]>
> > + */
> > +
> > +#include <linux/hid.h>
> > +#include <linux/usb.h>
>
> No need for linux/usb.h.

I'll fix that in v3.

>
> > +#include <linux/leds.h>
> > +#include <linux/device.h>
> > +#include <linux/errno.h>
> > +#include <dt-bindings/leds/common.h>
> > +
> > +#include "hid-ids.h"
> > +
> > +#define HID_USAGE_MAGIC_BL 0xff00000f
> > +
> > +#define APPLE_MAGIC_REPORT_ID_POWER 3
> > +#define APPLE_MAGIC_REPORT_ID_BRIGHTNESS 1
> > +
> > +struct apple_magic_backlight {
> > + struct led_classdev cdev;
> > + struct hid_device *hdev;
> > + struct hid_report *brightness;
> > + struct hid_report *power;
> > +};
> > +
> > +static void apple_magic_backlight_report_set(struct hid_report
> > *rep, u16 value, u8 rate) +{
>
> Could "value" be a s32? "logical_maximum" from the field is a s32,
> so there is no risk of truncation.

That makes sense, I'll put it in v3.

>
> > + 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_probe(struct hid_device *hdev,
> > + const struct hid_device_id
> > *id) +{
> > + struct apple_magic_backlight *backlight;
> > + int rc;
> > +
> > + rc = hid_parse(hdev);
> > + if (rc)
> > + return rc;
> > +
> > + /*
> > + * Ensure this usb endpoint is for the keyboard backlight,
> > not touchbar
> > + * backlight.
> > + */
> > + if (!(hdev->collection && hdev->collection[0].usage ==
> > HID_USAGE_MAGIC_BL))
> > + return -ENODEV;
>
> I don't think hdev->collection can ever be NULL.

I'll remove that check, I don't think it ever was null for me.

>
> Also personally I would prefer this:
>
> !hdev->collection || hdev->collection[0].usage != HID_USAGE_MAGIC_BL

That is neater, I'll use it in v3.

>
> Like it is done with the reports below.
>
> > +
> > + backlight = devm_kzalloc(&hdev->dev, sizeof(*backlight),
> > GFP_KERNEL);
> > + if (!backlight)
> > + return -ENOMEM;
> > +
> > + hid_set_drvdata(hdev, backlight);
>
> Is this needed?

Nope, I'll take that out in v3.

>
> > +
> > + rc = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
> > + if (rc)
> > + return rc;
> > +
> > + 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) {
> > + rc = -ENODEV;
> > + goto hw_stop;
> > + }
> > +
> > + backlight->hdev = hdev;
> > + backlight->cdev.name = ":white:"
> > LED_FUNCTION_KBD_BACKLIGHT;
>
> > + backlight->cdev.max_brightness =
> > backlight->brightness->field[0]->logical_maximum;
> > + 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); +
> > +hw_stop:
> > + hid_hw_stop(hdev);
> > + return rc;
> > +}
> > +
> > +static const struct hid_device_id apple_magic_backlight_hid_ids[]
> > = {
> > + { HID_USB_DEVICE(USB_VENDOR_ID_APPLE,
> > USB_DEVICE_ID_APPLE_TOUCHBAR_BACKLIGHT) },
> > + { }
> > +};
> > +MODULE_DEVICE_TABLE(hid, apple_magic_backlight_hid_ids);
> > +
> > +static struct hid_driver apple_magic_backlight_hid_driver = {
> > + .name = "apple-magic-backlight",
> > + .id_table = apple_magic_backlight_hid_ids,
> > + .probe = apple_magic_backlight_probe,
> > +};
> > +module_hid_driver(apple_magic_backlight_hid_driver);
> > +
> > +MODULE_DESCRIPTION("MacBook Magic Keyboard Backlight");
> > +MODULE_AUTHOR("Orlando Chamberlain <[email protected]>");
> > +MODULE_LICENSE("GPL");
> > --
> > 2.39.1
> >
>
> Note: Only your cover letter has the "v2" prefix.
> Normally git format-patch should apply this properly to all patches
> when using --reroll-count.

I realised that after I sent the patches, I had manually added v2 to
the cover letter but I forgot about the patches themselves. I didn't
know about --reroll-count, thanks!


2023-02-16 07:11:05

by Orlando Chamberlain

[permalink] [raw]
Subject: Re: [PATCH 2/2] HID: apple-magic-backlight: Add driver for keyboard backlight on internal Magic Keyboards

On Thu, 16 Feb 2023 15:12:28 +1100
Orlando Chamberlain <[email protected]> wrote:

> This driver adds support for the keyboard backlight on Intel T2 Macs
> with internal Magic Keyboards (MacBookPro16,x and MacBookAir9,1)
>
> Signed-off-by: Orlando Chamberlain <[email protected]>
> Co-developed-by: Kerem Karabay <[email protected]>
> Signed-off-by: Kerem Karabay <[email protected]>
> ---
> MAINTAINERS | 6 ++
> drivers/hid/Kconfig | 13 +++
> drivers/hid/Makefile | 1 +
> drivers/hid/apple-magic-backlight.c | 125

A general question to the hid/input folks:

Is it alright that this doesn't start with "hid-"? All the other
drivers start with that so I'm not sure if its an issue. If it is, then
I can rename it to "hid-apple-magic-backlight".

> ++++++++++++++++++++++++++++ 4 files changed, 145 insertions(+)
> create mode 100644 drivers/hid/apple-magic-backlight.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index fb1471cb5ed3..3319f0c3ed1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -9201,6 +9201,12 @@ F: include/linux/pm.h
> F: include/linux/suspend.h
> F: kernel/power/
>
> +HID APPLE MAGIC BACKLIGHT DRIVER
> +M: Orlando Chamberlain <[email protected]>
> +L: [email protected]
> +S: Maintained
> +F: drivers/hid/apple-magic-backlight.c
> +
> HID CORE LAYER
> M: Jiri Kosina <[email protected]>
> M: Benjamin Tissoires <[email protected]>
> diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
> index e2a5d30c8895..f4702d32ce2f 100644
> --- a/drivers/hid/Kconfig
> +++ b/drivers/hid/Kconfig
> @@ -130,6 +130,19 @@ config HID_APPLE
> Say Y here if you want support for keyboards of Apple
> iBooks, PowerBooks, MacBooks, MacBook Pros and Apple Aluminum.
>
> +config HID_APPLE_MAGIC_BACKLIGHT
> + tristate "Apple Magic Keyboard Backlight"
> + depends on USB_HID
> + depends on LEDS_CLASS
> + depends on NEW_LEDS
> + help
> + Say Y here if you want support for the keyboard backlight on
> Macs with
> + the magic keyboard (MacBookPro16,x and MacBookAir9,1). Note
> that this
> + driver is not for external magic keyboards.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called apple-magic-backlight.
> +
> config HID_APPLEIR
> tristate "Apple infrared receiver"
> depends on (USB_HID)
> diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> index e8014c1a2f8b..5cbfe85dd31b 100644
> --- a/drivers/hid/Makefile
> +++ b/drivers/hid/Makefile
> @@ -26,6 +26,7 @@ obj-$(CONFIG_HID_ACCUTOUCH) +=
> hid-accutouch.o obj-$(CONFIG_HID_ALPS) += hid-alps.o
> obj-$(CONFIG_HID_ACRUX) += hid-axff.o
> obj-$(CONFIG_HID_APPLE) += hid-apple.o
> +obj-$(CONFIG_HID_APPLE_MAGIC_BACKLIGHT) +=
> apple-magic-backlight.o obj-$(CONFIG_HID_APPLEIR) +=
> hid-appleir.o obj-$(CONFIG_HID_CREATIVE_SB0540) +=
> hid-creative-sb0540.o obj-$(CONFIG_HID_ASUS) +=
> hid-asus.o diff --git a/drivers/hid/apple-magic-backlight.c
> b/drivers/hid/apple-magic-backlight.c new file mode 100644
> index 000000000000..ed5bcf5bb599
> --- /dev/null
> +++ b/drivers/hid/apple-magic-backlight.c
> @@ -0,0 +1,125 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Apple Magic Keyboard Backlight Driver
> + *
> + * For Intel Macs with internal Magic Keyboard (MacBookPro16,1-4 and
> MacBookAir9,1)
> + *
> + * Copyright (c) 2022 Kerem Karabay <[email protected]>
> + * Copyright (c) 2023 Orlando Chamberlain <[email protected]>
> + */
> +
> +#include <linux/hid.h>
> +#include <linux/usb.h>
> +#include <linux/leds.h>
> +#include <linux/device.h>
> +#include <linux/errno.h>
> +#include <dt-bindings/leds/common.h>
> +
> +#include "hid-ids.h"
> +
> +#define HID_USAGE_MAGIC_BL 0xff00000f
> +
> +#define APPLE_MAGIC_REPORT_ID_POWER 3
> +#define APPLE_MAGIC_REPORT_ID_BRIGHTNESS 1
> +
> +struct apple_magic_backlight {
> + struct led_classdev cdev;
> + struct hid_device *hdev;
> + struct hid_report *brightness;
> + struct hid_report *power;
> +};
> +
> +static void apple_magic_backlight_report_set(struct hid_report *rep,
> u16 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_probe(struct hid_device *hdev,
> + const struct hid_device_id
> *id) +{
> + struct apple_magic_backlight *backlight;
> + int rc;
> +
> + rc = hid_parse(hdev);
> + if (rc)
> + return rc;
> +
> + /*
> + * Ensure this usb endpoint is for the keyboard backlight,
> not touchbar
> + * backlight.
> + */
> + if (!(hdev->collection && hdev->collection[0].usage ==
> HID_USAGE_MAGIC_BL))
> + return -ENODEV;
> +
> + backlight = devm_kzalloc(&hdev->dev, sizeof(*backlight),
> GFP_KERNEL);
> + if (!backlight)
> + return -ENOMEM;
> +
> + hid_set_drvdata(hdev, backlight);
> +
> + rc = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
> + if (rc)
> + return rc;
> +
> + 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) {
> + rc = -ENODEV;
> + goto hw_stop;
> + }
> +
> + backlight->hdev = hdev;
> + backlight->cdev.name = ":white:" LED_FUNCTION_KBD_BACKLIGHT;
> + backlight->cdev.max_brightness =
> backlight->brightness->field[0]->logical_maximum;
> + 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); +
> +hw_stop:
> + hid_hw_stop(hdev);
> + return rc;
> +}
> +
> +static const struct hid_device_id apple_magic_backlight_hid_ids[] = {
> + { HID_USB_DEVICE(USB_VENDOR_ID_APPLE,
> USB_DEVICE_ID_APPLE_TOUCHBAR_BACKLIGHT) },
> + { }
> +};
> +MODULE_DEVICE_TABLE(hid, apple_magic_backlight_hid_ids);
> +
> +static struct hid_driver apple_magic_backlight_hid_driver = {
> + .name = "apple-magic-backlight",
> + .id_table = apple_magic_backlight_hid_ids,
> + .probe = apple_magic_backlight_probe,
> +};
> +module_hid_driver(apple_magic_backlight_hid_driver);
> +
> +MODULE_DESCRIPTION("MacBook Magic Keyboard Backlight");
> +MODULE_AUTHOR("Orlando Chamberlain <[email protected]>");
> +MODULE_LICENSE("GPL");


2023-02-16 11:50:02

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH 2/2] HID: apple-magic-backlight: Add driver for keyboard backlight on internal Magic Keyboards

On Thu, Feb 16, 2023 at 10:15 AM Orlando Chamberlain
<[email protected]> wrote:
> On Thu, 16 Feb 2023 15:12:28 +1100
> Orlando Chamberlain <[email protected]> wrote:

...

> > drivers/hid/apple-magic-backlight.c | 125
>
> A general question to the hid/input folks:
>
> Is it alright that this doesn't start with "hid-"? All the other
> drivers start with that so I'm not sure if its an issue.

What makes apple so special?

> If it is, then
> I can rename it to "hid-apple-magic-backlight".

If there is a good justification of not doing that, put it into the
commit message.

--
With Best Regards,
Andy Shevchenko

2023-02-16 11:52:12

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH 2/2] HID: apple-magic-backlight: Add driver for keyboard backlight on internal Magic Keyboards

On Thu, Feb 16, 2023 at 7:41 AM Thomas Weißschuh <[email protected]> wrote:
> On Thu, Feb 16, 2023 at 03:12:28PM +1100, Orlando Chamberlain wrote:

...

> Note: Only your cover letter has the "v2" prefix.
> Normally git format-patch should apply this properly to all patches when
> using --reroll-count.

There is an option -v<X>, where <X> is a version applied to all
patches in the lot.

--
With Best Regards,
Andy Shevchenko