[PATCH v6 1/2] HID: logitech: Add MX Master over Bluetooth

[Mazin Rezk <mnrzk@protonmail.com>]

This patch adds support for the MX Master (b01e and b012) and also adds
foundational code for other Bluetooth LE HID++ devices to be added.

Some devices do not support short reports and thus have a quirk
(HIDPP_QUIRK_MISSING_SHORT_REPORTS) that forces short reports to be sent as
long reports. Since all Bluetooth LE HID++ devices seem to act this way,
HIDPP_QUIRK_CLASS_BLUETOOTH_LE aliases this quirk.

To allow for some space for future quirks, I changed the comment that
defines the bits reserved for classes from 2...20 to 2..15.

Signed-off-by: Mazin Rezk <mnrzk@protonmail.com>
---
 drivers/hid/hid-logitech-hidpp.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index 0179f7ed77e5..997b1056850a 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -59,7 +59,8 @@ MODULE_PARM_DESC(disable_tap_to_click,
 #define HIDPP_QUIRK_CLASS_G920			BIT(3)
 #define HIDPP_QUIRK_CLASS_K750			BIT(4)

-/* bits 2..20 are reserved for classes */
+/* bits 2..15 are reserved for classes */
+#define HIDPP_QUIRK_MISSING_SHORT_REPORTS	BIT(20)
 /* #define HIDPP_QUIRK_CONNECT_EVENTS		BIT(21) disabled */
 #define HIDPP_QUIRK_WTP_PHYSICAL_BUTTONS	BIT(22)
 #define HIDPP_QUIRK_NO_HIDINPUT			BIT(23)
@@ -81,6 +82,8 @@ MODULE_PARM_DESC(disable_tap_to_click,
 					 HIDPP_QUIRK_HI_RES_SCROLL_X2120 | \
 					 HIDPP_QUIRK_HI_RES_SCROLL_X2121)

+#define HIDPP_QUIRK_CLASS_BLUETOOTH_LE	HIDPP_QUIRK_MISSING_SHORT_REPORTS
+
 #define HIDPP_QUIRK_DELAYED_INIT		HIDPP_QUIRK_NO_HIDINPUT

 #define HIDPP_CAPABILITY_HIDPP10_BATTERY	BIT(0)
@@ -340,6 +343,12 @@ static int hidpp_send_rap_command_sync(struct hidpp_device *hidpp_dev,
 	struct hidpp_report *message;
 	int ret, max_count;

+	/* Force long reports on devices that do not support short reports */
+	if (hidpp_dev->quirks & HIDPP_QUIRK_MISSING_SHORT_REPORTS &&
+	    report_id == REPORT_ID_HIDPP_SHORT)
+		report_id = REPORT_ID_HIDPP_LONG;
+
+
 	switch (report_id) {
 	case REPORT_ID_HIDPP_SHORT:
 		max_count = HIDPP_REPORT_SHORT_LENGTH - 4;
@@ -3482,6 +3491,12 @@ static bool hidpp_validate_report(struct hid_device *hdev, int id,

 static bool hidpp_validate_device(struct hid_device *hdev)
 {
+	struct hidpp_device *hidpp = hid_get_drvdata(hdev);
+	/* Skip the short report check if the device does not support it */
+	if (hidpp->quirks & HIDPP_QUIRK_MISSING_SHORT_REPORTS)
+		return hidpp_validate_report(hdev, REPORT_ID_HIDPP_LONG,
+					     HIDPP_REPORT_LONG_LENGTH, false);
+
 	return hidpp_validate_report(hdev, REPORT_ID_HIDPP_SHORT,
 				     HIDPP_REPORT_SHORT_LENGTH, false) &&
 	       hidpp_validate_report(hdev, REPORT_ID_HIDPP_LONG,
@@ -3773,6 +3788,13 @@ static const struct hid_device_id hidpp_devices[] = {
 	{ /* MX5500 keyboard over Bluetooth */
 	  HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb30b),
 	  .driver_data = HIDPP_QUIRK_HIDPP_CONSUMER_VENDOR_KEYS },
+	{ /* MX Master mouse over Bluetooth */
+	  HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb012),
+	  .driver_data = HIDPP_QUIRK_HI_RES_SCROLL_X2121 |
+			 HIDPP_QUIRK_CLASS_BLUETOOTH_LE },
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_LOGITECH, 0xb01e),
+	  .driver_data = HIDPP_QUIRK_HI_RES_SCROLL_X2121 |
+			 HIDPP_QUIRK_CLASS_BLUETOOTH_LE },
 	{}
 };

--
2.23.0