HID: mcp2221: don't connect hidraw
authorEnrik Berkhan <Enrik.Berkhan@inka.de>
Thu, 3 Nov 2022 22:27:12 +0000 (23:27 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 31 Dec 2022 12:14:46 +0000 (13:14 +0100)
commit 67c90d14018775556d5420382ace86521421f9ff upstream.

The MCP2221 driver should not connect to the hidraw userspace interface,
as it needs exclusive access to the chip.

If you want to use /dev/hidrawX with the MCP2221, you need to avoid
binding this driver to the device and use the hid generic driver instead
(e.g. using udev rules).

Cc: stable@vger.kernel.org
Reported-by: Sven Zühlsdorf <sven.zuehlsdorf@vigem.de>
Signed-off-by: Enrik Berkhan <Enrik.Berkhan@inka.de>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20221103222714.21566-2-Enrik.Berkhan@inka.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/hid/hid-mcp2221.c

index de52e9f..560eeec 100644 (file)
@@ -840,12 +840,19 @@ static int mcp2221_probe(struct hid_device *hdev,
                return ret;
        }
 
-       ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+       /*
+        * This driver uses the .raw_event callback and therefore does not need any
+        * HID_CONNECT_xxx flags.
+        */
+       ret = hid_hw_start(hdev, 0);
        if (ret) {
                hid_err(hdev, "can't start hardware\n");
                return ret;
        }
 
+       hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n", hdev->version >> 8,
+                       hdev->version & 0xff, hdev->name, hdev->phys);
+
        ret = hid_hw_open(hdev);
        if (ret) {
                hid_err(hdev, "can't open device\n");
@@ -870,8 +877,7 @@ static int mcp2221_probe(struct hid_device *hdev,
        mcp->adapter.retries = 1;
        mcp->adapter.dev.parent = &hdev->dev;
        snprintf(mcp->adapter.name, sizeof(mcp->adapter.name),
-                       "MCP2221 usb-i2c bridge on hidraw%d",
-                       ((struct hidraw *)hdev->hidraw)->minor);
+                       "MCP2221 usb-i2c bridge");
 
        ret = i2c_add_adapter(&mcp->adapter);
        if (ret) {