Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 354 insertions, 0 deletions

diff --git a/drivers/hid/hid-letsketch.c b/drivers/hid/hid-letsketch.c
new file mode 100644
index 000000000..b52e93a91
--- /dev/null
+++ b/drivers/hid/hid-letsketch.c
@@ -0,0 +1,354 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021 Hans de Goede <hdegoede@redhat.com>
+ *
+ * Driver for the LetSketch / VSON WP9620N drawing tablet.
+ * This drawing tablet is also sold under other brand names such as Case U,
+ * presumably this driver will work for all of them. But it has only been
+ * tested with a LetSketch WP9620N model.
+ *
+ * These tablets also work without a special HID driver, but then only part
+ * of the active area works and both the pad and stylus buttons are hardwired
+ * to special key-combos. E.g. the 2 stylus buttons send right mouse clicks /
+ * resp. "e" key presses.
+ *
+ * This device has 4 USB interfaces:
+ *
+ * Interface 0 EP 0x81 bootclass mouse, rdesc len 18, report id 0x08,
+ *                                                    Application(ff00.0001)
+ *  This interface sends raw event input reports in a custom format, but only
+ *  after doing the special dance from letsketch_probe(). After enabling this
+ *  interface the other 3 interfaces are disabled.
+ *
+ * Interface 1 EP 0x82 bootclass mouse, rdesc len 83, report id 0x0a, Tablet
+ *  This interface sends absolute events for the pen, including pressure,
+ *  but only for some part of the active area due to special "aspect ratio"
+ *  correction and only half by default since it assumes it will be used
+ *  with a phone in portraid mode, while using the tablet in landscape mode.
+ *  Also stylus + pad button events are not reported here.
+ *
+ * Interface 2 EP 0x83 bootclass keybd, rdesc len 64, report id none, Std Kbd
+ *  This interfaces send various hard-coded key-combos for the pad buttons
+ *  and "e" keypresses for the 2nd stylus button
+ *
+ * Interface 3 EP 0x84 bootclass mouse, rdesc len 75, report id 0x01, Std Mouse
+ *  This reports right-click mouse-button events for the 1st stylus button
+ */
+#include <linux/device.h>
+#include <linux/input.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+#include <linux/timer.h>
+#include <linux/usb.h>
+
+#include <linux/unaligned.h>
+
+#include "hid-ids.h"
+
+#define LETSKETCH_RAW_IF		0
+
+#define LETSKETCH_RAW_DATA_LEN		12
+#define LETSKETCH_RAW_REPORT_ID		8
+
+#define LETSKETCH_PAD_BUTTONS		5
+
+#define LETSKETCH_INFO_STR_IDX_BEGIN	0xc8
+#define LETSKETCH_INFO_STR_IDX_END	0xca
+
+#define LETSKETCH_GET_STRING_RETRIES	5
+
+struct letsketch_data {
+	struct hid_device *hdev;
+	struct input_dev *input_tablet;
+	struct input_dev *input_tablet_pad;
+	struct timer_list inrange_timer;
+};
+
+static int letsketch_open(struct input_dev *dev)
+{
+	struct letsketch_data *data = input_get_drvdata(dev);
+
+	return hid_hw_open(data->hdev);
+}
+
+static void letsketch_close(struct input_dev *dev)
+{
+	struct letsketch_data *data = input_get_drvdata(dev);
+
+	hid_hw_close(data->hdev);
+}
+
+static struct input_dev *letsketch_alloc_input_dev(struct letsketch_data *data)
+{
+	struct input_dev *input;
+
+	input = devm_input_allocate_device(&data->hdev->dev);
+	if (!input)
+		return NULL;
+
+	input->id.bustype = data->hdev->bus;
+	input->id.vendor  = data->hdev->vendor;
+	input->id.product = data->hdev->product;
+	input->id.version = data->hdev->bus;
+	input->phys = data->hdev->phys;
+	input->uniq = data->hdev->uniq;
+	input->open = letsketch_open;
+	input->close = letsketch_close;
+
+	input_set_drvdata(input, data);
+
+	return input;
+}
+
+static int letsketch_setup_input_tablet(struct letsketch_data *data)
+{
+	struct input_dev *input;
+
+	input = letsketch_alloc_input_dev(data);
+	if (!input)
+		return -ENOMEM;
+
+	input_set_abs_params(input, ABS_X, 0, 50800, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, 31750, 0, 0);
+	input_set_abs_params(input, ABS_PRESSURE, 0, 8192, 0, 0);
+	input_abs_set_res(input, ABS_X, 240);
+	input_abs_set_res(input, ABS_Y, 225);
+	input_set_capability(input, EV_KEY, BTN_TOUCH);
+	input_set_capability(input, EV_KEY, BTN_TOOL_PEN);
+	input_set_capability(input, EV_KEY, BTN_STYLUS);
+	input_set_capability(input, EV_KEY, BTN_STYLUS2);
+
+	/* All known brands selling this tablet use WP9620[N] as model name */
+	input->name = "WP9620 Tablet";
+
+	data->input_tablet = input;
+
+	return input_register_device(data->input_tablet);
+}
+
+static int letsketch_setup_input_tablet_pad(struct letsketch_data *data)
+{
+	struct input_dev *input;
+	int i;
+
+	input = letsketch_alloc_input_dev(data);
+	if (!input)
+		return -ENOMEM;
+
+	for (i = 0; i < LETSKETCH_PAD_BUTTONS; i++)
+		input_set_capability(input, EV_KEY, BTN_0 + i);
+
+	/*
+	 * These are never send on the pad input_dev, but must be set
+	 * on the Pad to make udev / libwacom happy.
+	 */
+	input_set_abs_params(input, ABS_X, 0, 1, 0, 0);
+	input_set_abs_params(input, ABS_Y, 0, 1, 0, 0);
+	input_set_capability(input, EV_KEY, BTN_STYLUS);
+
+	input->name = "WP9620 Pad";
+
+	data->input_tablet_pad = input;
+
+	return input_register_device(data->input_tablet_pad);
+}
+
+static void letsketch_inrange_timeout(struct timer_list *t)
+{
+	struct letsketch_data *data = timer_container_of(data, t,
+							 inrange_timer);
+	struct input_dev *input = data->input_tablet;
+
+	input_report_key(input, BTN_TOOL_PEN, 0);
+	input_sync(input);
+}
+
+static int letsketch_raw_event(struct hid_device *hdev,
+			       struct hid_report *report,
+			       u8 *raw_data, int size)
+{
+	struct letsketch_data *data = hid_get_drvdata(hdev);
+	struct input_dev *input;
+	int i;
+
+	if (size != LETSKETCH_RAW_DATA_LEN || raw_data[0] != LETSKETCH_RAW_REPORT_ID)
+		return 0;
+
+	switch (raw_data[1] & 0xf0) {
+	case 0x80: /* Pen data */
+		input = data->input_tablet;
+		input_report_key(input, BTN_TOOL_PEN, 1);
+		input_report_key(input, BTN_TOUCH, raw_data[1] & 0x01);
+		input_report_key(input, BTN_STYLUS, raw_data[1] & 0x02);
+		input_report_key(input, BTN_STYLUS2, raw_data[1] & 0x04);
+		input_report_abs(input, ABS_X,
+				 get_unaligned_le16(raw_data + 2));
+		input_report_abs(input, ABS_Y,
+				 get_unaligned_le16(raw_data + 4));
+		input_report_abs(input, ABS_PRESSURE,
+				 get_unaligned_le16(raw_data + 6));
+		/*
+		 * There is no out of range event, so use a timer for this
+		 * when in range we get an event approx. every 8 ms.
+		 */
+		mod_timer(&data->inrange_timer, jiffies + msecs_to_jiffies(100));
+		break;
+	case 0xe0: /* Pad data */
+		input = data->input_tablet_pad;
+		for (i = 0; i < LETSKETCH_PAD_BUTTONS; i++)
+			input_report_key(input, BTN_0 + i, raw_data[4] == (i + 1));
+		break;
+	default:
+		hid_warn(data->hdev, "Warning unknown data header: 0x%02x\n",
+			 raw_data[0]);
+		return 0;
+	}
+
+	input_sync(input);
+	return 0;
+}
+
+/*
+ * The tablets magic handshake to put it in raw mode relies on getting
+ * string descriptors. But the firmware is buggy and does not like it if
+ * we do this too fast. Even if we go slow sometimes the usb_string() call
+ * fails. Ignore errors and retry it a couple of times if necessary.
+ */
+static int letsketch_get_string(struct usb_device *udev, int index, char *buf, int size)
+{
+	int i, ret;
+
+	for (i = 0; i < LETSKETCH_GET_STRING_RETRIES; i++) {
+		usleep_range(5000, 7000);
+		ret = usb_string(udev, index, buf, size);
+		if (ret > 0)
+			return 0;
+	}
+
+	dev_err(&udev->dev, "Max retries (%d) exceeded reading string descriptor %d\n",
+		LETSKETCH_GET_STRING_RETRIES, index);
+	return ret ? ret : -EIO;
+}
+
+static int letsketch_probe(struct hid_device *hdev, const struct hid_device_id *id)
+{
+	struct device *dev = &hdev->dev;
+	struct letsketch_data *data;
+	struct usb_interface *intf;
+	struct usb_device *udev;
+	char buf[256];
+	int i, ret;
+
+	if (!hid_is_usb(hdev))
+		return -ENODEV;
+
+	intf = to_usb_interface(hdev->dev.parent);
+	if (intf->altsetting->desc.bInterfaceNumber != LETSKETCH_RAW_IF)
+		return -ENODEV; /* Ignore the other interfaces */
+
+	udev = interface_to_usbdev(intf);
+
+	/*
+	 * Instead of using a set-feature request, or even a custom USB ctrl
+	 * message the tablet needs this elaborate magic reading of USB
+	 * string descriptors to kick it into raw mode. This is what the
+	 * Windows drivers are seen doing in an USB trace under Windows.
+	 */
+	for (i = LETSKETCH_INFO_STR_IDX_BEGIN; i <= LETSKETCH_INFO_STR_IDX_END; i++) {
+		ret = letsketch_get_string(udev, i, buf, sizeof(buf));
+		if (ret)
+			return ret;
+
+		hid_info(hdev, "Device info: %s\n", buf);
+	}
+
+	for (i = 1; i <= 250; i++) {
+		ret = letsketch_get_string(udev, i, buf, sizeof(buf));
+		if (ret)
+			return ret;
+	}
+
+	ret = letsketch_get_string(udev, 0x64, buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	ret = letsketch_get_string(udev, LETSKETCH_INFO_STR_IDX_BEGIN, buf, sizeof(buf));
+	if (ret)
+		return ret;
+
+	/*
+	 * The tablet should be in raw mode now, end with a final delay before
+	 * doing further IO to the device.
+	 */
+	usleep_range(5000, 7000);
+
+	ret = hid_parse(hdev);
+	if (ret)
+		return ret;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->hdev = hdev;
+	timer_setup(&data->inrange_timer, letsketch_inrange_timeout, 0);
+	hid_set_drvdata(hdev, data);
+
+	ret = letsketch_setup_input_tablet(data);
+	if (ret)
+		goto err_shutdown_timer;
+
+	ret = letsketch_setup_input_tablet_pad(data);
+	if (ret)
+		goto err_shutdown_timer;
+
+	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+	if (ret)
+		goto err_shutdown_timer;
+
+	return 0;
+
+err_shutdown_timer:
+	/*
+	 * Drain any pending callback and permanently disable the timer
+	 * before devm releases data: if hid_hw_start() enabled I/O on an
+	 * always-poll-quirk device and then failed, raw_event may have
+	 * armed the timer already.
+	 */
+	timer_shutdown_sync(&data->inrange_timer);
+	return ret;
+}
+
+static void letsketch_remove(struct hid_device *hdev)
+{
+	struct letsketch_data *data = hid_get_drvdata(hdev);
+
+	/*
+	 * hid_hw_stop() synchronously kills the URBs that deliver
+	 * raw_event(), so once it returns no path can re-arm
+	 * inrange_timer.  timer_shutdown_sync() then drains any
+	 * in-flight callback and permanently disables further
+	 * mod_timer() calls before devm releases data.
+	 */
+	hid_hw_stop(hdev);
+	timer_shutdown_sync(&data->inrange_timer);
+}
+
+static const struct hid_device_id letsketch_devices[] = {
+	{ HID_USB_DEVICE(USB_VENDOR_ID_LETSKETCH, USB_DEVICE_ID_WP9620N) },
+	{ }
+};
+MODULE_DEVICE_TABLE(hid, letsketch_devices);
+
+static struct hid_driver letsketch_driver = {
+	.name = "letsketch",
+	.id_table = letsketch_devices,
+	.probe = letsketch_probe,
+	.remove = letsketch_remove,
+	.raw_event = letsketch_raw_event,
+};
+module_hid_driver(letsketch_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_DESCRIPTION("Driver for the LetSketch / VSON WP9620N drawing tablet");
+MODULE_LICENSE("GPL");