As soon as the GPIO driver part will be enabled in mcp2221_probe(), the first HID reports will be exchanged with the chip because the GPIO driver immediately calls mcp_gpio_get_direction(). HID I/O has to be enabled explicitly during mcp2221_probe() to receive response reports. Otherwise, all four mcp_gpio_get_direction() calls will run into the four second timeout of mcp_send_report(), which will block the driver for about 16s during startup. A very similar patch appeared some time ago in https://lore.kernel.org/r/20210818152743.163929-1-tobias.junghans@xxxxxxxx which obviously got lost somehow. CC: Tobias Junghans <tobias.junghans@xxxxxxxx> Signed-off-by: Enrik Berkhan <Enrik.Berkhan@xxxxxxx> --- drivers/hid/hid-mcp2221.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/hid/hid-mcp2221.c b/drivers/hid/hid-mcp2221.c index e61dd039354b..0705526231ec 100644 --- a/drivers/hid/hid-mcp2221.c +++ b/drivers/hid/hid-mcp2221.c @@ -1178,6 +1178,9 @@ static int mcp2221_probe(struct hid_device *hdev, mcp->gc->can_sleep = 1; mcp->gc->parent = &hdev->dev; + /* Enable reception of HID reports during GPIO initialization */ + hid_device_io_start(hdev); + ret = devm_gpiochip_add_data(&hdev->dev, mcp->gc, mcp); if (ret) return ret; -- 2.34.1
