HID: logitech-dj: add support for 27 MHz receivers

Most Logitech wireless keyboard and mice using the 27 MHz are hidpp10
devices, add support to logitech-dj for their receivers.

Doing so leads to 2 improvements:

1) All these devices share the same USB product-id for their receiver,
making it impossible to properly map some special keys / buttons
which differ from device to device. Adding support to logitech-dj to
see these as hidpp10 devices allows us to get the actual device-id
from the keyboard / mouse.

2) It enables battery-monitoring of these devices

This patch uses a new HID group for 27Mhz devices, since the logitech-hidpp
code needs to be able to differentiate them from other devices instantiated
by the logitech-dj code.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

4 files changed, 94 insertions, 4 deletions

diff --git a/drivers/hid/hid-lg.c b/drivers/hid/hid-lg.c
index 5d419a95b6c2..36d725fdb199 100644
--- a/drivers/hid/hid-lg.c
+++ b/drivers/hid/hid-lg.c
@@ -876,8 +876,6 @@ static const struct hid_device_id lg_devices[] = {
                 .driver_data = LG_RDESC | LG_WIRELESS },
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_S510_RECEIVER),
                 .driver_data = LG_RDESC | LG_WIRELESS },
-        { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_S510_RECEIVER_2),
-                .driver_data = LG_RDESC | LG_WIRELESS },
 
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_RECEIVER),
                 .driver_data = LG_BAD_RELATIVE_KEYS },
diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c
index 9ece9aca40a0..3004ca91b76b 100644
--- a/drivers/hid/hid-logitech-dj.c
+++ b/drivers/hid/hid-logitech-dj.c
@@ -106,6 +106,7 @@
 #define HIDPP_PARAM_DEVICE_INFO                 0x01
 #define HIDPP_PARAM_EQUAD_LSB                   0x02
 #define HIDPP_PARAM_EQUAD_MSB                   0x03
+#define HIDPP_PARAM_27MHZ_DEVID                 0x03
 #define HIDPP_DEVICE_TYPE_MASK                  GENMASK(3, 0)
 #define HIDPP_LINK_STATUS_MASK                  BIT(6)
 
@@ -120,6 +121,7 @@ enum recvr_type {
         recvr_type_dj,
         recvr_type_hidpp,
         recvr_type_gaming_hidpp,
+        recvr_type_27mhz,
 };
 
 struct dj_report {
@@ -248,6 +250,44 @@ static const char mse_descriptor[] = {
         0xC0,                   /*  END_COLLECTION                      */
 };
 
+/* Mouse descriptor (2) for 27 MHz receiver, only 8 buttons */
+static const char mse_27mhz_descriptor[] = {
+        0x05, 0x01,             /*  USAGE_PAGE (Generic Desktop)        */
+        0x09, 0x02,             /*  USAGE (Mouse)                       */
+        0xA1, 0x01,             /*  COLLECTION (Application)            */
+        0x85, 0x02,             /*    REPORT_ID = 2                     */
+        0x09, 0x01,             /*    USAGE (pointer)                   */
+        0xA1, 0x00,             /*    COLLECTION (physical)             */
+        0x05, 0x09,             /*      USAGE_PAGE (buttons)            */
+        0x19, 0x01,             /*      USAGE_MIN (1)                   */
+        0x29, 0x08,             /*      USAGE_MAX (8)                   */
+        0x15, 0x00,             /*      LOGICAL_MIN (0)                 */
+        0x25, 0x01,             /*      LOGICAL_MAX (1)                 */
+        0x95, 0x08,             /*      REPORT_COUNT (8)                */
+        0x75, 0x01,             /*      REPORT_SIZE (1)                 */
+        0x81, 0x02,             /*      INPUT (data var abs)            */
+        0x05, 0x01,             /*      USAGE_PAGE (generic desktop)    */
+        0x16, 0x01, 0xF8,       /*      LOGICAL_MIN (-2047)             */
+        0x26, 0xFF, 0x07,       /*      LOGICAL_MAX (2047)              */
+        0x75, 0x0C,             /*      REPORT_SIZE (12)                */
+        0x95, 0x02,             /*      REPORT_COUNT (2)                */
+        0x09, 0x30,             /*      USAGE (X)                       */
+        0x09, 0x31,             /*      USAGE (Y)                       */
+        0x81, 0x06,             /*      INPUT                           */
+        0x15, 0x81,             /*      LOGICAL_MIN (-127)              */
+        0x25, 0x7F,             /*      LOGICAL_MAX (127)               */
+        0x75, 0x08,             /*      REPORT_SIZE (8)                 */
+        0x95, 0x01,             /*      REPORT_COUNT (1)                */
+        0x09, 0x38,             /*      USAGE (wheel)                   */
+        0x81, 0x06,             /*      INPUT                           */
+        0x05, 0x0C,             /*      USAGE_PAGE(consumer)            */
+        0x0A, 0x38, 0x02,       /*      USAGE(AC Pan)                   */
+        0x95, 0x01,             /*      REPORT_COUNT (1)                */
+        0x81, 0x06,             /*      INPUT                           */
+        0xC0,                   /*    END_COLLECTION                    */
+        0xC0,                   /*  END_COLLECTION                      */
+};
+
 /* Gaming Mouse descriptor (2) */
 static const char mse_high_res_descriptor[] = {
         0x05, 0x01,             /*  USAGE_PAGE (Generic Desktop)        */
@@ -596,7 +636,10 @@ static void logi_dj_recv_add_djhid_device(struct dj_receiver_dev *djrcv_dev,
                 "Logitech Unifying Device. Wireless PID:%04x",
                 dj_hiddev->product);
 
-        dj_hiddev->group = HID_GROUP_LOGITECH_DJ_DEVICE;
+        if (djrcv_dev->type == recvr_type_27mhz)
+                dj_hiddev->group = HID_GROUP_LOGITECH_27MHZ_DEVICE;
+        else
+                dj_hiddev->group = HID_GROUP_LOGITECH_DJ_DEVICE;
 
         memcpy(dj_hiddev->phys, djrcv_hdev->phys, sizeof(djrcv_hdev->phys));
         snprintf(tmpstr, sizeof(tmpstr), ":%d", device_index);
@@ -782,6 +825,28 @@ static void logi_hidpp_dev_conn_notif_equad(struct hidpp_event *hidpp_report,
         }
 }
 
+static void logi_hidpp_dev_conn_notif_27mhz(struct hid_device *hdev,
+                                            struct hidpp_event *hidpp_report,
+                                            struct dj_workitem *workitem)
+{
+        workitem->type = WORKITEM_TYPE_PAIRED;
+        workitem->quad_id_lsb = hidpp_report->params[HIDPP_PARAM_27MHZ_DEVID];
+        switch (hidpp_report->device_index) {
+        case 1: /* Index 1 is always a mouse */
+        case 2: /* Index 2 is always a mouse */
+                workitem->reports_supported |= STD_MOUSE;
+                break;
+        case 3: /* Index 3 is always the keyboard */
+        case 4: /* Index 4 is used for an optional separate numpad */
+                workitem->reports_supported |= STD_KEYBOARD | MULTIMEDIA |
+                                               POWER_KEYS;
+                break;
+        default:
+                hid_warn(hdev, "%s: unexpected device-index %d", __func__,
+                         hidpp_report->device_index);
+        }
+}
+
 static void logi_hidpp_recv_queue_notif(struct hid_device *hdev,
                                         struct hidpp_event *hidpp_report)
 {
@@ -799,6 +864,7 @@ static void logi_hidpp_recv_queue_notif(struct hid_device *hdev,
                 break;
         case 0x02:
                 device_type = "27 Mhz";
+                logi_hidpp_dev_conn_notif_27mhz(hdev, hidpp_report, &workitem);
                 break;
         case 0x03:
                 device_type = "QUAD or eQUAD";
@@ -1186,6 +1252,9 @@ static int logi_dj_ll_parse(struct hid_device *hid)
                 if (djdev->dj_receiver_dev->type == recvr_type_gaming_hidpp)
                         rdcat(rdesc, &rsize, mse_high_res_descriptor,
                               sizeof(mse_high_res_descriptor));
+                else if (djdev->dj_receiver_dev->type == recvr_type_27mhz)
+                        rdcat(rdesc, &rsize, mse_27mhz_descriptor,
+                              sizeof(mse_27mhz_descriptor));
                 else
                         rdcat(rdesc, &rsize, mse_descriptor,
                               sizeof(mse_descriptor));
@@ -1357,6 +1426,25 @@ static int logi_dj_hidpp_event(struct hid_device *hdev,
         spin_lock_irqsave(&djrcv_dev->lock, flags);
 
         dj_dev = djrcv_dev->paired_dj_devices[device_index];
+
+        /*
+         * With 27 MHz receivers, we do not get an explicit unpair event,
+         * remove the old device if the user has paired a *different* device.
+         */
+        if (djrcv_dev->type == recvr_type_27mhz && dj_dev &&
+            hidpp_report->sub_id == REPORT_TYPE_NOTIF_DEVICE_CONNECTED &&
+            hidpp_report->params[HIDPP_PARAM_PROTO_TYPE] == 0x02 &&
+            hidpp_report->params[HIDPP_PARAM_27MHZ_DEVID] !=
+                                                dj_dev->hdev->product) {
+                struct dj_workitem workitem = {
+                        .device_index = hidpp_report->device_index,
+                        .type = WORKITEM_TYPE_UNPAIRED,
+                };
+                kfifo_in(&djrcv_dev->notif_fifo, &workitem, sizeof(workitem));
+                /* logi_hidpp_recv_queue_notif will queue the work */
+                dj_dev = NULL;
+        }
+
         if (dj_dev) {
                 logi_dj_recv_forward_report(dj_dev, data, size);
         } else {
@@ -1628,6 +1716,10 @@ static const struct hid_device_id logi_dj_receivers[] = {
           HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
                 USB_DEVICE_ID_LOGITECH_NANO_RECEIVER_GAMING),
          .driver_data = recvr_type_gaming_hidpp},
+        { /* Logitech 27 MHz HID++ 1.0 receiver (0xc517) */
+          HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH,
+                USB_DEVICE_ID_S510_RECEIVER_2),
+         .driver_data = recvr_type_27mhz},
         {}
 };
 
diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c
index 426753482494..fea7f7ff5ab1 100644
--- a/drivers/hid/hid-quirks.c
+++ b/drivers/hid/hid-quirks.c
@@ -432,7 +432,6 @@ static const struct hid_device_id hid_have_special_driver[] = {
 #if IS_ENABLED(CONFIG_HID_LOGITECH)
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_MX3000_RECEIVER) },
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_S510_RECEIVER) },
-        { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_S510_RECEIVER_2) },
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_RECEIVER) },
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_DINOVO_DESKTOP) },
         { HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_DINOVO_EDGE) },
diff --git a/include/linux/hid.h b/include/linux/hid.h
index f9707d1dcb58..9f161fa5cbd4 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -382,6 +382,7 @@ struct hid_item {
 #define HID_GROUP_WACOM                         0x0101
 #define HID_GROUP_LOGITECH_DJ_DEVICE            0x0102
 #define HID_GROUP_STEAM                         0x0103
+#define HID_GROUP_LOGITECH_27MHZ_DEVICE         0x0104
 
 /*
  * HID protocol status