diff mbox series

[4/5] HID: apple-ibridge: Add Apple iBridge HID driver for T1 chip.

Message ID 20210228012643.69944-5-ronald@innovation.ch (mailing list archive)
State New
Headers show
Series Touch Bar and ALS support for MacBook Pro's | expand

Commit Message

Life is hard, and then you die Feb. 28, 2021, 1:26 a.m. UTC
The iBridge device provides access to several devices, including:
- the Touch Bar
- the iSight webcam
- the light sensor
- the fingerprint sensor

This driver provides the core support for managing the iBridge device
and the access to the underlying devices. In particular, the
functionality for the touch bar and light sensor is exposed via USB HID
interfaces, and on devices with the T1 chip one of the HID devices is
used for both functions. So this driver creates virtual HID devices, one
per top-level report collection on each HID device (for a total of 3
virtual HID devices). The sub-drivers then bind to these virtual HID
devices.

This way the Touch Bar and ALS drivers can be kept in their own modules,
while at the same time making them look very much like as if they were
connected to the real HID devices. And those drivers then work (mostly)
without further changes on MacBooks with the T2 chip that don't need
this driver.

Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
---
 drivers/hid/Kconfig         |  16 +
 drivers/hid/Makefile        |   1 +
 drivers/hid/apple-ibridge.c | 682 ++++++++++++++++++++++++++++++++++++
 drivers/hid/apple-ibridge.h |  15 +
 drivers/hid/hid-ids.h       |   1 +
 drivers/hid/hid-quirks.c    |   3 +
 6 files changed, 718 insertions(+)
 create mode 100644 drivers/hid/apple-ibridge.c
 create mode 100644 drivers/hid/apple-ibridge.h

Comments

Jonathan Cameron Feb. 28, 2021, 3:02 p.m. UTC | #1
On Sat, 27 Feb 2021 17:26:42 -0800
Ronald Tschalär <ronald@innovation.ch> wrote:

> The iBridge device provides access to several devices, including:
> - the Touch Bar
> - the iSight webcam
> - the light sensor
> - the fingerprint sensor
> 
> This driver provides the core support for managing the iBridge device
> and the access to the underlying devices. In particular, the
> functionality for the touch bar and light sensor is exposed via USB HID
> interfaces, and on devices with the T1 chip one of the HID devices is
> used for both functions. So this driver creates virtual HID devices, one
> per top-level report collection on each HID device (for a total of 3
> virtual HID devices). The sub-drivers then bind to these virtual HID
> devices.
> 
> This way the Touch Bar and ALS drivers can be kept in their own modules,
> while at the same time making them look very much like as if they were
> connected to the real HID devices. And those drivers then work (mostly)
> without further changes on MacBooks with the T2 chip that don't need
> this driver.
> 
> Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
Hi Ronald.

This is far from my specialty but mostly looks sensible to me.

Just one thing stood out that I couldn't understand. See below.

Jonathan

> new file mode 100644
> index 0000000000000..5f2b71c199746
> --- /dev/null
> +++ b/drivers/hid/apple-ibridge.c
> @@ -0,0 +1,682 @@

...

> +
> +#ifdef CONFIG_PM
> +/**
> + * appleib_forward_int_op() - Forward a hid-driver callback to all drivers on
> + * all virtual HID devices attached to the given real HID device.
> + * @hdev the real hid-device
> + * @forward a function that calls the callback on the given driver
> + * @args arguments for the forward function
> + *
> + * This is for callbacks that return a status as an int.
> + *
> + * Returns: 0 on success, or the first error returned by the @forward function.
> + */
> +static int appleib_forward_int_op(struct hid_device *hdev,
> +				  int (*forward)(struct hid_driver *,
> +						 struct hid_device *, void *),
> +				  void *args)
> +{
> +	struct appleib_hid_dev_info *hdev_info = hid_get_drvdata(hdev);
> +	struct hid_device *sub_hdev;
> +	int rc = 0;
> +	int i;
> +
> +	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
> +		sub_hdev = hdev_info->sub_hdevs[i];
> +		if (sub_hdev->driver) {
> +			rc = forward(sub_hdev->driver, sub_hdev, args);
> +			if (rc)
> +				break;

return rc; here would be cleaner.

> +		}
> +
> +		break;

This is unusual.  It's a for loop but as far as I can see only first iteration
can ever run as we exit the loop at this break if we haven't done so earlier.
What is the intent here?

> +	}
> +
> +	return rc;
> +}
Life is hard, and then you die March 1, 2021, 12:04 a.m. UTC | #2
Hi Jonathan,

On Sun, Feb 28, 2021 at 03:02:39PM +0000, Jonathan Cameron wrote:
> On Sat, 27 Feb 2021 17:26:42 -0800
> Ronald Tschal?r <ronald@innovation.ch> wrote:
[snip]
> > +#ifdef CONFIG_PM
> > +/**
> > + * appleib_forward_int_op() - Forward a hid-driver callback to all drivers on
> > + * all virtual HID devices attached to the given real HID device.
> > + * @hdev the real hid-device
> > + * @forward a function that calls the callback on the given driver
> > + * @args arguments for the forward function
> > + *
> > + * This is for callbacks that return a status as an int.
> > + *
> > + * Returns: 0 on success, or the first error returned by the @forward function.
> > + */
> > +static int appleib_forward_int_op(struct hid_device *hdev,
> > +				  int (*forward)(struct hid_driver *,
> > +						 struct hid_device *, void *),
> > +				  void *args)
> > +{
> > +	struct appleib_hid_dev_info *hdev_info = hid_get_drvdata(hdev);
> > +	struct hid_device *sub_hdev;
> > +	int rc = 0;
> > +	int i;
> > +
> > +	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
> > +		sub_hdev = hdev_info->sub_hdevs[i];
> > +		if (sub_hdev->driver) {
> > +			rc = forward(sub_hdev->driver, sub_hdev, args);
> > +			if (rc)
> > +				break;
> 
> return rc; here would be cleaner.
> 
> > +		}
> > +
> > +		break;
> 
> This is unusual.  It's a for loop but as far as I can see only first iteration
> can ever run as we exit the loop at this break if we haven't done so earlier.
> What is the intent here?
> 
> > +	}
> > +
> > +	return rc;
> > +}

Ho boy, good catch! This is simply a mistake. As you say, it should
(and does now) read:

	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
		sub_hdev = hdev_info->sub_hdevs[i];
		if (sub_hdev->driver) {
			rc = forward(sub_hdev->driver, sub_hdev, args);
			if (rc)
				return rc;
		}
	}

	return rc;

Thanks.


  Cheers,

  Ronald
Andy Shevchenko March 1, 2021, 2:12 p.m. UTC | #3
On Sun, Feb 28, 2021 at 3:30 AM Ronald Tschalär <ronald@innovation.ch> wrote:
>
> The iBridge device provides access to several devices, including:
> - the Touch Bar
> - the iSight webcam
> - the light sensor
> - the fingerprint sensor
>
> This driver provides the core support for managing the iBridge device
> and the access to the underlying devices. In particular, the
> functionality for the touch bar and light sensor is exposed via USB HID
> interfaces, and on devices with the T1 chip one of the HID devices is
> used for both functions. So this driver creates virtual HID devices, one
> per top-level report collection on each HID device (for a total of 3
> virtual HID devices). The sub-drivers then bind to these virtual HID
> devices.
>
> This way the Touch Bar and ALS drivers can be kept in their own modules,
> while at the same time making them look very much like as if they were
> connected to the real HID devices. And those drivers then work (mostly)
> without further changes on MacBooks with the T2 chip that don't need
> this driver.

Thanks for the contribution.
Before I'll do a full review, two concerns:
 - don't do ACPI drivers, please, in the new code. Use platform driver
infrastructure for that
 - dependencies (see below)

...

> +config HID_APPLE_IBRIDGE
> +       tristate "Apple iBridge"

> +       depends on ACPI
> +       depends on USB_HID

> +       depends on X86 || COMPILE_TEST

I haven't found anything ACPI specific there, so this should be rather

depends on (X86 && ACPI) || COMPILE_TEST

> +       imply HID_SENSOR_HUB
> +       imply HID_SENSOR_ALS
> +       help
> +         This module provides the core support for the Apple T1 chip found
> +         on 2016 and 2017 MacBookPro's, also known as the iBridge. The drivers
> +         for the Touch Bar (apple-touchbar) and light sensor (hid-sensor-hub
> +         and hid-sensor-als) need to be enabled separately.
> +
> +         To compile this driver as a module, choose M here: the
> +         module will be called apple-ibridge.
diff mbox series

Patch

diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 09fa75a2b289e..579c45c3e36e5 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -136,6 +136,22 @@  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_IBRIDGE
+	tristate "Apple iBridge"
+	depends on ACPI
+	depends on USB_HID
+	depends on X86 || COMPILE_TEST
+	imply HID_SENSOR_HUB
+	imply HID_SENSOR_ALS
+	help
+	  This module provides the core support for the Apple T1 chip found
+	  on 2016 and 2017 MacBookPro's, also known as the iBridge. The drivers
+	  for the Touch Bar (apple-touchbar) and light sensor (hid-sensor-hub
+	  and hid-sensor-als) need to be enabled separately.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called apple-ibridge.
+
 config HID_APPLEIR
 	tristate "Apple infrared receiver"
 	depends on (USB_HID)
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index 014d21fe7dac6..d29a3934bfaa9 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-$(CONFIG_HID_APPLE_IBRIDGE)	+= apple-ibridge.o
 obj-$(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-ibridge.c b/drivers/hid/apple-ibridge.c
new file mode 100644
index 0000000000000..5f2b71c199746
--- /dev/null
+++ b/drivers/hid/apple-ibridge.c
@@ -0,0 +1,682 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Apple iBridge Driver
+ *
+ * Copyright (c) 2018 Ronald Tschalär
+ */
+
+/**
+ * DOC: Overview
+ *
+ * 2016 and 2017 MacBookPro models with a Touch Bar (MacBookPro13,[23] and
+ * MacBookPro14,[23]) have an Apple iBridge chip (also known as T1 chip) which
+ * exposes the touch bar, built-in webcam (iSight), ambient light sensor, and
+ * Secure Enclave Processor (SEP) for TouchID. It shows up in the system as a
+ * USB device with 3 configurations: 'Default iBridge Interfaces', 'Default
+ * iBridge Interfaces(OS X)', and 'Default iBridge Interfaces(Recovery)'.
+ *
+ * In the first (default after boot) configuration, 4 usb interfaces are
+ * exposed: 2 related to the webcam, and 2 USB HID interfaces representing
+ * the touch bar and the ambient light sensor. The webcam interfaces are
+ * already handled by the uvcvideo driver. However, there is a problem with
+ * the other two interfaces: one of them contains functionality (HID reports)
+ * used by both the touch bar and the ALS, which is an issue because the kernel
+ * allows only one driver to be attached to a given device. This driver exists
+ * to solve this issue.
+ *
+ * This driver is implemented as a HID driver that attaches to both HID
+ * interfaces and in turn creates several virtual child HID devices, one for
+ * each top-level collection found in each interfaces report descriptor. The
+ * touch bar and ALS drivers then attach to these virtual HID devices, and this
+ * driver forwards the operations between the real and virtual devices.
+ *
+ * One important aspect of this approach is that resulting (virtual) HID
+ * devices look much like the HID devices found on the later MacBookPro models
+ * which have a T2 chip, where there are separate USB interfaces for the touch
+ * bar and ALS functionality, which means that the touch bar and ALS drivers
+ * work (mostly) the same on both types of models.
+ *
+ * Lastly, this driver also takes care of the power-management for the
+ * iBridge when suspending and resuming.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include "hid-ids.h"
+#include "../hid/usbhid/usbhid.h"
+#include "apple-ibridge.h"
+
+#define APPLEIB_BASIC_CONFIG	1
+
+#define	LOG_DEV(ib_dev)		(&(ib_dev)->acpi_dev->dev)
+
+static struct hid_device_id appleib_sub_hid_ids[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LINUX_FOUNDATION,
+			 USB_DEVICE_ID_IBRIDGE_TB) },
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LINUX_FOUNDATION,
+			 USB_DEVICE_ID_IBRIDGE_ALS) },
+};
+
+static struct {
+	unsigned int usage;
+	struct hid_device_id *dev_id;
+} appleib_usage_map[] = {
+	/* Default iBridge configuration, key inputs and mode settings */
+	{ 0x00010006, &appleib_sub_hid_ids[0] },
+	/* OS X iBridge configuration, digitizer inputs */
+	{ 0x000D0005, &appleib_sub_hid_ids[0] },
+	/* All iBridge configurations, display/DFR settings */
+	{ 0xFF120001, &appleib_sub_hid_ids[0] },
+	/* All iBridge configurations, ALS */
+	{ 0x00200041, &appleib_sub_hid_ids[1] },
+};
+
+struct appleib_device {
+	struct acpi_device	*acpi_dev;
+	acpi_handle		asoc_socw;
+};
+
+struct appleib_hid_dev_info {
+	struct hid_device	*hdev;
+	struct hid_device	*sub_hdevs[ARRAY_SIZE(appleib_sub_hid_ids)];
+	bool			sub_open[ARRAY_SIZE(appleib_sub_hid_ids)];
+};
+
+static int appleib_hid_raw_event(struct hid_device *hdev,
+				 struct hid_report *report, u8 *data, int size)
+{
+	struct appleib_hid_dev_info *hdev_info = hid_get_drvdata(hdev);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
+		if (READ_ONCE(hdev_info->sub_open[i]))
+			hid_input_report(hdev_info->sub_hdevs[i], report->type,
+					 data, size, 0);
+	}
+
+	return 0;
+}
+
+static __u8 *appleib_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+				  unsigned int *rsize)
+{
+	/* Some fields have a size of 64 bits, which according to HID 1.11
+	 * Section 8.4 is not valid ("An item field cannot span more than 4
+	 * bytes in a report"). Furthermore, hid_field_extract() complains
+	 * when encountering such a field. So turn them into two 32-bit fields
+	 * instead.
+	 */
+
+	if (*rsize == 634 &&
+	    /* Usage Page 0xff12 (vendor defined) */
+	    rdesc[212] == 0x06 && rdesc[213] == 0x12 && rdesc[214] == 0xff &&
+	    /* Usage 0x51 */
+	    rdesc[416] == 0x09 && rdesc[417] == 0x51 &&
+	    /* report size 64 */
+	    rdesc[432] == 0x75 && rdesc[433] == 64 &&
+	    /* report count 1 */
+	    rdesc[434] == 0x95 && rdesc[435] == 1) {
+		rdesc[433] = 32;
+		rdesc[435] = 2;
+		hid_dbg(hdev, "Fixed up first 64-bit field\n");
+	}
+
+	if (*rsize == 634 &&
+	    /* Usage Page 0xff12 (vendor defined) */
+	    rdesc[212] == 0x06 && rdesc[213] == 0x12 && rdesc[214] == 0xff &&
+	    /* Usage 0x51 */
+	    rdesc[611] == 0x09 && rdesc[612] == 0x51 &&
+	    /* report size 64 */
+	    rdesc[627] == 0x75 && rdesc[628] == 64 &&
+	    /* report count 1 */
+	    rdesc[629] == 0x95 && rdesc[630] == 1) {
+		rdesc[628] = 32;
+		rdesc[630] = 2;
+		hid_dbg(hdev, "Fixed up second 64-bit field\n");
+	}
+
+	return rdesc;
+}
+
+#ifdef CONFIG_PM
+/**
+ * appleib_forward_int_op() - Forward a hid-driver callback to all drivers on
+ * all virtual HID devices attached to the given real HID device.
+ * @hdev the real hid-device
+ * @forward a function that calls the callback on the given driver
+ * @args arguments for the forward function
+ *
+ * This is for callbacks that return a status as an int.
+ *
+ * Returns: 0 on success, or the first error returned by the @forward function.
+ */
+static int appleib_forward_int_op(struct hid_device *hdev,
+				  int (*forward)(struct hid_driver *,
+						 struct hid_device *, void *),
+				  void *args)
+{
+	struct appleib_hid_dev_info *hdev_info = hid_get_drvdata(hdev);
+	struct hid_device *sub_hdev;
+	int rc = 0;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
+		sub_hdev = hdev_info->sub_hdevs[i];
+		if (sub_hdev->driver) {
+			rc = forward(sub_hdev->driver, sub_hdev, args);
+			if (rc)
+				break;
+		}
+
+		break;
+	}
+
+	return rc;
+}
+
+static int appleib_hid_suspend_fwd(struct hid_driver *drv,
+				   struct hid_device *hdev, void *args)
+{
+	int rc = 0;
+
+	if (drv->suspend)
+		rc = drv->suspend(hdev, *(pm_message_t *)args);
+
+	return rc;
+}
+
+static int appleib_hid_suspend(struct hid_device *hdev, pm_message_t message)
+{
+	return appleib_forward_int_op(hdev, appleib_hid_suspend_fwd, &message);
+}
+
+static int appleib_hid_resume_fwd(struct hid_driver *drv,
+				  struct hid_device *hdev, void *args)
+{
+	int rc = 0;
+
+	if (drv->resume)
+		rc = drv->resume(hdev);
+
+	return rc;
+}
+
+static int appleib_hid_resume(struct hid_device *hdev)
+{
+	return appleib_forward_int_op(hdev, appleib_hid_resume_fwd, NULL);
+}
+
+static int appleib_hid_reset_resume_fwd(struct hid_driver *drv,
+					struct hid_device *hdev, void *args)
+{
+	int rc = 0;
+
+	if (drv->reset_resume)
+		rc = drv->reset_resume(hdev);
+
+	return rc;
+}
+
+static int appleib_hid_reset_resume(struct hid_device *hdev)
+{
+	return appleib_forward_int_op(hdev, appleib_hid_reset_resume_fwd, NULL);
+}
+#endif /* CONFIG_PM */
+
+static int appleib_ll_start(struct hid_device *hdev)
+{
+	return 0;
+}
+
+static void appleib_ll_stop(struct hid_device *hdev)
+{
+}
+
+static int appleib_set_open(struct hid_device *hdev, bool open)
+{
+	struct appleib_hid_dev_info *hdev_info = hdev->driver_data;
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
+		/*
+		 * hid_hw_open(), and hence appleib_ll_open(), is called
+		 * from the driver's probe function, which in turn is called
+		 * while adding the sub-hdev; but at this point we haven't yet
+		 * added the sub-hdev to our list. So if we don't find the
+		 * sub-hdev in our list assume it's in the process of being
+		 * added and set the flag on the first unset sub-hdev.
+		 */
+		if (hdev_info->sub_hdevs[i] == hdev ||
+		    !hdev_info->sub_hdevs[i]) {
+			WRITE_ONCE(hdev_info->sub_open[i], open);
+			return 0;
+		}
+	}
+
+	return -ENODEV;
+}
+
+static int appleib_ll_open(struct hid_device *hdev)
+{
+	return appleib_set_open(hdev, true);
+}
+
+static void appleib_ll_close(struct hid_device *hdev)
+{
+	appleib_set_open(hdev, false);
+}
+
+static int appleib_ll_power(struct hid_device *hdev, int level)
+{
+	struct appleib_hid_dev_info *hdev_info = hdev->driver_data;
+
+	return hid_hw_power(hdev_info->hdev, level);
+}
+
+static int appleib_ll_parse(struct hid_device *hdev)
+{
+	/* we've already called hid_parse_report() */
+	return 0;
+}
+
+static void appleib_ll_request(struct hid_device *hdev,
+			       struct hid_report *report, int reqtype)
+{
+	struct appleib_hid_dev_info *hdev_info = hdev->driver_data;
+
+	hid_hw_request(hdev_info->hdev, report, reqtype);
+}
+
+static int appleib_ll_wait(struct hid_device *hdev)
+{
+	struct appleib_hid_dev_info *hdev_info = hdev->driver_data;
+
+	hid_hw_wait(hdev_info->hdev);
+	return 0;
+}
+
+static int appleib_ll_raw_request(struct hid_device *hdev,
+				  unsigned char reportnum, __u8 *buf,
+				  size_t len, unsigned char rtype, int reqtype)
+{
+	struct appleib_hid_dev_info *hdev_info = hdev->driver_data;
+
+	return hid_hw_raw_request(hdev_info->hdev, reportnum, buf, len, rtype,
+				  reqtype);
+}
+
+static int appleib_ll_output_report(struct hid_device *hdev, __u8 *buf,
+				    size_t len)
+{
+	struct appleib_hid_dev_info *hdev_info = hdev->driver_data;
+
+	return hid_hw_output_report(hdev_info->hdev, buf, len);
+}
+
+static struct hid_ll_driver appleib_ll_driver = {
+	.start = appleib_ll_start,
+	.stop = appleib_ll_stop,
+	.open = appleib_ll_open,
+	.close = appleib_ll_close,
+	.power = appleib_ll_power,
+	.parse = appleib_ll_parse,
+	.request = appleib_ll_request,
+	.wait = appleib_ll_wait,
+	.raw_request = appleib_ll_raw_request,
+	.output_report = appleib_ll_output_report,
+};
+
+static __u8 *appleib_find_collection(__u8 *start, __u8 *end,
+				     unsigned int *usage)
+{
+	struct hid_item item;
+	int depth = 0;
+
+	*usage = 0;
+
+	while ((start = hid_fetch_item(start, end, &item)) != NULL) {
+		if (item.type == HID_ITEM_TYPE_MAIN) {
+			switch (item.tag) {
+			case HID_MAIN_ITEM_TAG_BEGIN_COLLECTION:
+				depth++;
+				break;
+
+			case HID_MAIN_ITEM_TAG_END_COLLECTION:
+				depth--;
+				if (depth <= 0)
+					return start;
+				break;
+			}
+		} else if (item.type == HID_ITEM_TYPE_GLOBAL &&
+			   item.tag == HID_GLOBAL_ITEM_TAG_USAGE_PAGE &&
+			   depth == 0) {
+			*usage = (*usage & 0x0000FFFF) |
+				 ((hid_item_udata(&item) & 0xFFFF) << 16);
+		} else if (item.type == HID_ITEM_TYPE_LOCAL &&
+			   item.tag == HID_LOCAL_ITEM_TAG_USAGE &&
+			   depth == 0) {
+			*usage = (*usage & 0xFFFF0000) |
+				 (hid_item_udata(&item) & 0xFFFF);
+		}
+	}
+
+	return end;
+}
+
+static struct hid_device_id *appleib_find_dev_id_for_usage(unsigned int usage)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(appleib_usage_map); i++) {
+		if (appleib_usage_map[i].usage == usage)
+			return appleib_usage_map[i].dev_id;
+	}
+
+	return NULL;
+}
+
+static struct hid_device *
+appleib_add_sub_dev(struct appleib_hid_dev_info *hdev_info,
+		    struct hid_device_id *dev_id, u8 *rdesc, size_t rsize)
+{
+	struct hid_device *sub_hdev;
+	int rc;
+
+	sub_hdev = hid_allocate_device();
+	if (IS_ERR(sub_hdev))
+		return sub_hdev;
+
+	sub_hdev->dev.parent = &hdev_info->hdev->dev;
+
+	sub_hdev->bus = dev_id->bus;
+	sub_hdev->group = dev_id->group;
+	sub_hdev->vendor = dev_id->vendor;
+	sub_hdev->product = dev_id->product;
+
+	sub_hdev->ll_driver = &appleib_ll_driver;
+
+	snprintf(sub_hdev->name, sizeof(sub_hdev->name),
+		 "iBridge Virtual HID %s/%04x:%04x",
+		 dev_name(sub_hdev->dev.parent), sub_hdev->vendor,
+		 sub_hdev->product);
+
+	sub_hdev->driver_data = hdev_info;
+
+	rc = hid_parse_report(sub_hdev, rdesc, rsize);
+	if (rc) {
+		hid_destroy_device(sub_hdev);
+		return ERR_PTR(rc);
+	}
+
+	rc = hid_add_device(sub_hdev);
+	if (rc) {
+		hid_destroy_device(sub_hdev);
+		return ERR_PTR(rc);
+	}
+
+	return sub_hdev;
+}
+
+static struct appleib_hid_dev_info *appleib_add_device(struct hid_device *hdev)
+{
+	struct appleib_hid_dev_info *hdev_info;
+	__u8 *start = hdev->dev_rdesc;
+	__u8 *end = start + hdev->dev_rsize;
+	__u8 *pos;
+	struct hid_device_id *dev_id;
+	unsigned int usage;
+	int i;
+
+	hdev_info = devm_kzalloc(&hdev->dev, sizeof(*hdev_info), GFP_KERNEL);
+	if (!hdev_info)
+		return ERR_PTR(-ENOMEM);
+
+	hdev_info->hdev = hdev;
+
+	for (i = 0; ; ) {
+		pos = appleib_find_collection(start, end, &usage);
+
+		dev_id = appleib_find_dev_id_for_usage(usage);
+		if (!dev_id) {
+			hid_warn(hdev, "Unknown collection encountered with usage %x\n",
+				 usage);
+
+		} else if (i >= ARRAY_SIZE(hdev_info->sub_hdevs)) {
+			hid_warn(hdev, "Too many collections encountered - ignoring for usage %x\n",
+				 usage);
+		} else {
+			hdev_info->sub_hdevs[i] =
+				appleib_add_sub_dev(hdev_info, dev_id, start,
+						    pos - start);
+			if (IS_ERR(hdev_info->sub_hdevs[i])) {
+				while (i-- > 0)
+					hid_destroy_device(hdev_info->sub_hdevs[i]);
+				return (void *)hdev_info->sub_hdevs[i];
+			}
+
+			i++;
+		}
+
+		start = pos;
+		if (start >= end)
+			break;
+	}
+
+	return hdev_info;
+}
+
+static void appleib_remove_device(struct hid_device *hdev)
+{
+	struct appleib_hid_dev_info *hdev_info = hid_get_drvdata(hdev);
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(hdev_info->sub_hdevs); i++) {
+		if (hdev_info->sub_hdevs[i])
+			hid_destroy_device(hdev_info->sub_hdevs[i]);
+	}
+
+	hid_set_drvdata(hdev, NULL);
+}
+
+static int appleib_hid_probe(struct hid_device *hdev,
+			     const struct hid_device_id *id)
+{
+	struct appleib_hid_dev_info *hdev_info;
+	struct usb_device *udev;
+	int rc;
+
+	/* check and set usb config first */
+	udev = hid_to_usb_dev(hdev);
+
+	if (udev->actconfig->desc.bConfigurationValue != APPLEIB_BASIC_CONFIG) {
+		rc = usb_driver_set_configuration(udev, APPLEIB_BASIC_CONFIG);
+		return rc ? rc : -ENODEV;
+	}
+
+	rc = hid_parse(hdev);
+	if (rc) {
+		hid_err(hdev, "ib: hid parse failed (%d)\n", rc);
+		goto error;
+	}
+
+	rc = hid_hw_start(hdev, HID_CONNECT_DRIVER);
+	if (rc) {
+		hid_err(hdev, "ib: hw start failed (%d)\n", rc);
+		goto error;
+	}
+
+	hdev_info = appleib_add_device(hdev);
+	if (IS_ERR(hdev_info)) {
+		rc = PTR_ERR(hdev_info);
+		goto stop_hw;
+	}
+
+	hid_set_drvdata(hdev, hdev_info);
+
+	rc = hid_hw_open(hdev);
+	if (rc) {
+		hid_err(hdev, "ib: failed to open hid: %d\n", rc);
+		goto remove_dev;
+	}
+
+	return 0;
+
+remove_dev:
+	appleib_remove_device(hdev);
+stop_hw:
+	hid_hw_stop(hdev);
+error:
+	return rc;
+}
+
+static void appleib_hid_remove(struct hid_device *hdev)
+{
+	hid_hw_close(hdev);
+	appleib_remove_device(hdev);
+	hid_hw_stop(hdev);
+}
+
+static const struct hid_device_id appleib_hid_ids[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_IBRIDGE) },
+	{ },
+};
+
+static struct hid_driver appleib_hid_driver = {
+	.name = "apple-ibridge-hid",
+	.id_table = appleib_hid_ids,
+	.probe = appleib_hid_probe,
+	.remove = appleib_hid_remove,
+	.raw_event = appleib_hid_raw_event,
+	.report_fixup = appleib_report_fixup,
+#ifdef CONFIG_PM
+	.suspend = appleib_hid_suspend,
+	.resume = appleib_hid_resume,
+	.reset_resume = appleib_hid_reset_resume,
+#endif
+};
+
+static struct appleib_device *appleib_alloc_device(struct acpi_device *acpi_dev)
+{
+	struct appleib_device *ib_dev;
+	acpi_status sts;
+
+	ib_dev = devm_kzalloc(&acpi_dev->dev, sizeof(*ib_dev), GFP_KERNEL);
+	if (!ib_dev)
+		return ERR_PTR(-ENOMEM);
+
+	ib_dev->acpi_dev = acpi_dev;
+
+	/* get iBridge acpi power control method for suspend/resume */
+	sts = acpi_get_handle(acpi_dev->handle, "SOCW", &ib_dev->asoc_socw);
+	if (ACPI_FAILURE(sts)) {
+		dev_err(LOG_DEV(ib_dev),
+			"Error getting handle for ASOC.SOCW method: %s\n",
+			acpi_format_exception(sts));
+		return ERR_PTR(-ENXIO);
+	}
+
+	/* ensure iBridge is powered on */
+	sts = acpi_execute_simple_method(ib_dev->asoc_socw, NULL, 1);
+	if (ACPI_FAILURE(sts))
+		dev_warn(LOG_DEV(ib_dev), "SOCW(1) failed: %s\n",
+			 acpi_format_exception(sts));
+
+	return ib_dev;
+}
+
+static int appleib_probe(struct acpi_device *acpi)
+{
+	struct appleib_device *ib_dev;
+	int ret;
+
+	ib_dev = appleib_alloc_device(acpi);
+	if (IS_ERR(ib_dev))
+		return PTR_ERR(ib_dev);
+
+	ret = hid_register_driver(&appleib_hid_driver);
+	if (ret) {
+		dev_err(LOG_DEV(ib_dev), "Error registering hid driver: %d\n",
+			ret);
+		return ret;
+	}
+
+	acpi->driver_data = ib_dev;
+
+	return 0;
+}
+
+static int appleib_remove(struct acpi_device *acpi)
+{
+	hid_unregister_driver(&appleib_hid_driver);
+
+	return 0;
+}
+
+static int appleib_suspend(struct device *dev)
+{
+	struct appleib_device *ib_dev;
+	int rc;
+
+	ib_dev = acpi_driver_data(to_acpi_device(dev));
+
+	rc = acpi_execute_simple_method(ib_dev->asoc_socw, NULL, 0);
+	if (ACPI_FAILURE(rc))
+		dev_warn(dev, "SOCW(0) failed: %s\n",
+			 acpi_format_exception(rc));
+
+	return 0;
+}
+
+static int appleib_resume(struct device *dev)
+{
+	struct appleib_device *ib_dev;
+	int rc;
+
+	ib_dev = acpi_driver_data(to_acpi_device(dev));
+
+	rc = acpi_execute_simple_method(ib_dev->asoc_socw, NULL, 1);
+	if (ACPI_FAILURE(rc))
+		dev_warn(dev, "SOCW(1) failed: %s\n",
+			 acpi_format_exception(rc));
+
+	return 0;
+}
+
+static const struct dev_pm_ops appleib_pm = {
+	.suspend = appleib_suspend,
+	.resume = appleib_resume,
+	.restore = appleib_resume,
+};
+
+static const struct acpi_device_id appleib_acpi_match[] = {
+	{ "APP7777", 0 },
+	{ },
+};
+
+MODULE_DEVICE_TABLE(acpi, appleib_acpi_match);
+
+static struct acpi_driver appleib_driver = {
+	.name		= "apple-ibridge",
+	.class		= "apple_ibridge",
+	.owner		= THIS_MODULE,
+	.ids		= appleib_acpi_match,
+	.ops		= {
+		.add		= appleib_probe,
+		.remove		= appleib_remove,
+	},
+	.drv		= {
+		.pm		= &appleib_pm,
+	},
+};
+
+module_acpi_driver(appleib_driver)
+
+MODULE_AUTHOR("Ronald Tschalär");
+MODULE_DESCRIPTION("Apple iBridge driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/hid/apple-ibridge.h b/drivers/hid/apple-ibridge.h
new file mode 100644
index 0000000000000..8aefcf61589aa
--- /dev/null
+++ b/drivers/hid/apple-ibridge.h
@@ -0,0 +1,15 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Apple iBridge Driver
+ *
+ * Copyright (c) 2018 Ronald Tschalär
+ */
+
+#ifndef __LINUX_APPLE_IBRDIGE_H
+#define __LINUX_APPLE_IBRDIGE_H
+
+#define USB_VENDOR_ID_LINUX_FOUNDATION	0x1d6b
+#define USB_DEVICE_ID_IBRIDGE_TB	0x0301
+#define USB_DEVICE_ID_IBRIDGE_ALS	0x0302
+
+#endif
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 5ba0aa1d23353..6b5d565e73dc2 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -172,6 +172,7 @@ 
 #define USB_DEVICE_ID_APPLE_IRCONTROL3	0x8241
 #define USB_DEVICE_ID_APPLE_IRCONTROL4	0x8242
 #define USB_DEVICE_ID_APPLE_IRCONTROL5	0x8243
+#define USB_DEVICE_ID_APPLE_IBRIDGE	0x8600
 
 #define USB_VENDOR_ID_ASUS		0x0486
 #define USB_DEVICE_ID_ASUS_T91MT	0x0185
diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c
index d9ca874dffac3..731ddfd0e9efe 100644
--- a/drivers/hid/hid-quirks.c
+++ b/drivers/hid/hid-quirks.c
@@ -300,6 +300,9 @@  static const struct hid_device_id hid_have_special_driver[] = {
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_FOUNTAIN_TP_ONLY) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_GEYSER1_TP_ONLY) },
 #endif
+#if IS_ENABLED(CONFIG_HID_APPLE_IBRIDGE)
+	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_IBRIDGE) },
+#endif
 #if IS_ENABLED(CONFIG_HID_APPLEIR)
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_IRCONTROL) },
 	{ HID_USB_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_IRCONTROL2) },