From: Maxim Devaev <mdevaev@xxxxxxxxx> commit afcff6dc690e24d636a41fd4bee6057e7c70eebd upstream. The USB HID standard declares mandatory support for GET_IDLE and SET_IDLE requests for Boot Keyboard. Most hosts can handle their absence, but others like some old/strange UEFIs and BIOSes consider this a critical error and refuse to work with f_hid. This primitive implementation of saving and returning idle is sufficient to meet the requirements of the standard and these devices. Acked-by: Felipe Balbi <balbi@xxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Maxim Devaev <mdevaev@xxxxxxxxx> Link: https://lore.kernel.org/r/20210721180351.129450-1-mdevaev@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/gadget/function/f_hid.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) --- a/drivers/usb/gadget/function/f_hid.c +++ b/drivers/usb/gadget/function/f_hid.c @@ -41,6 +41,7 @@ struct f_hidg { unsigned char bInterfaceSubClass; unsigned char bInterfaceProtocol; unsigned char protocol; + unsigned char idle; unsigned short report_desc_length; char *report_desc; unsigned short report_length; @@ -529,6 +530,14 @@ static int hidg_setup(struct usb_functio goto respond; break; + case ((USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 + | HID_REQ_GET_IDLE): + VDBG(cdev, "get_idle\n"); + length = min_t(unsigned int, length, 1); + ((u8 *) req->buf)[0] = hidg->idle; + goto respond; + break; + case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 | HID_REQ_SET_REPORT): VDBG(cdev, "set_report | wLength=%d\n", ctrl->wLength); @@ -552,6 +561,14 @@ static int hidg_setup(struct usb_functio goto stall; break; + case ((USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE) << 8 + | HID_REQ_SET_IDLE): + VDBG(cdev, "set_idle\n"); + length = 0; + hidg->idle = value; + goto respond; + break; + case ((USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_INTERFACE) << 8 | USB_REQ_GET_DESCRIPTOR): switch (value >> 8) { @@ -779,6 +796,7 @@ static int hidg_bind(struct usb_configur hidg_interface_desc.bInterfaceSubClass = hidg->bInterfaceSubClass; hidg_interface_desc.bInterfaceProtocol = hidg->bInterfaceProtocol; hidg->protocol = HID_REPORT_PROTOCOL; + hidg->idle = 1; hidg_ss_in_ep_desc.wMaxPacketSize = cpu_to_le16(hidg->report_length); hidg_ss_in_comp_desc.wBytesPerInterval = cpu_to_le16(hidg->report_length);
