From: Maxim Devaev mdevaev@gmail.com
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@kernel.org Cc: stable stable@vger.kernel.org Signed-off-by: Maxim Devaev mdevaev@gmail.com Link: https://lore.kernel.org/r/20210721180351.129450-1-mdevaev@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- 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 @@ -45,6 +45,7 @@ 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; @@ -533,6 +534,14 @@ 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); @@ -556,6 +565,14 @@ 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) { @@ -783,6 +800,7 @@ 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);