HID: rmi: Use SET_REPORT request on control endpoint for Acer Switch 3 and 5

The touchpad on the cover keyboard for the Acer Switch 3 and 5 does not
work as-is under Linux. Both devices have the same usb id for the cover
keyboard.

The kernel correctly assigns the hid-rmi driver to the device using usbhid
for transport.
Any attempts of hid-rmi to talk to the device using hid_hw_output_report
fail however as usbhid does not have a working urbout due to the lack of
any out endpoints.

Looking through Wireshark usbmon recordings from the Windows Synaptics
driver for this computer running inside of QEMU shows that it should be
using SET_REPORT requests instead.

This replaces the hid_hw_output_report in hid-rmi with a
hid_hw_raw_request for this device, which is at least enough to enable
the kernel to get working multi-touch input.

Signed-off-by: Tobias Auerochs <tobi291019@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index 1c8c72093b5a2ec25af405cfff95319f10f098b2..22456586034ae3fc113234f368c31909efbef3eb 100644 (file)
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -1089,6 +1089,7 @@
 #define USB_DEVICE_ID_SYNAPTICS_HD     0x0ac3
 #define USB_DEVICE_ID_SYNAPTICS_QUAD_HD        0x1ac3
 #define USB_DEVICE_ID_SYNAPTICS_TP_V103        0x5710
+#define USB_DEVICE_ID_SYNAPTICS_ACER_SWITCH5   0x81a7
 
 #define USB_VENDOR_ID_TEXAS_INSTRUMENTS        0x2047
 #define USB_DEVICE_ID_TEXAS_INSTRUMENTS_LENOVO_YOGA    0x0855

diff --git a/drivers/hid/hid-rmi.c b/drivers/hid/hid-rmi.c
index 9e33165250a34c7acf49e5e43c0a8ea482fdb1ec..34465a7c37131da28f4e569afbaaee76caa37c64 100644 (file)
--- a/drivers/hid/hid-rmi.c
+++ b/drivers/hid/hid-rmi.c
@@ -39,6 +39,7 @@
 /* device flags */
 #define RMI_DEVICE                     BIT(0)
 #define RMI_DEVICE_HAS_PHYS_BUTTONS    BIT(1)
+#define RMI_DEVICE_OUTPUT_SET_REPORT   BIT(2)
 
 /*
  * retrieve the ctrl registers
@@ -167,9 +168,19 @@ static int rmi_set_mode(struct hid_device *hdev, u8 mode)
 
 static int rmi_write_report(struct hid_device *hdev, u8 *report, int len)
 {
+       struct rmi_data *data = hid_get_drvdata(hdev);
        int ret;
 
-       ret = hid_hw_output_report(hdev, (void *)report, len);
+       if (data->device_flags & RMI_DEVICE_OUTPUT_SET_REPORT) {
+               /*
+                * Talk to device by using SET_REPORT requests instead.
+                */
+               ret = hid_hw_raw_request(hdev, report[0], report,
+                               len, HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
+       } else {
+               ret = hid_hw_output_report(hdev, (void *)report, len);
+       }
+
        if (ret < 0) {
                dev_err(&hdev->dev, "failed to write hid report (%d)\n", ret);
                return ret;
@@ -751,6 +762,8 @@ static const struct hid_device_id rmi_id[] = {
                .driver_data = RMI_DEVICE_HAS_PHYS_BUTTONS },
        { HID_USB_DEVICE(USB_VENDOR_ID_LENOVO, USB_DEVICE_ID_LENOVO_X1_COVER) },
        { HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_REZEL) },
+       { HID_USB_DEVICE(USB_VENDOR_ID_SYNAPTICS, USB_DEVICE_ID_SYNAPTICS_ACER_SWITCH5),
+               .driver_data = RMI_DEVICE_OUTPUT_SET_REPORT },
        { HID_DEVICE(HID_BUS_ANY, HID_GROUP_RMI, HID_ANY_ID, HID_ANY_ID) },
        { }
 };