1 files changed, 40 insertions, 9 deletions

diff --git a/chip/stm32/usb_hid.c b/chip/stm32/usb_hid.c
index b316585e77..79668ad0de 100644
--- a/chip/stm32/usb_hid.c
+++ b/chip/stm32/usb_hid.c
@@ -40,23 +40,54 @@ void hid_reset(int ep, usb_uint *hid_ep_buf, int len)
 		(0 << 12) /* RX Disabled */;
 }
 
+/*
+ * Keep track of state in case we need to be called multiple times,
+ * if the report length is bigger than 64 bytes.
+ */
+static int report_left;
+static const uint8_t *report_ptr;
+
 int hid_iface_request(usb_uint *ep0_buf_rx, usb_uint *ep0_buf_tx,
 		      const uint8_t *report_desc, int report_size)
 {
-	if ((ep0_buf_rx[0] == (USB_DIR_IN | USB_RECIP_INTERFACE |
+	if (!ep0_buf_rx) {
+		/*
+		 * Continue previous transfer. We ignore report_desc/size here,
+		 * which is fine as only one GET_DESCRIPTOR command comes at a
+		 * time.
+		 */
+		if (report_left == 0)
+			return -1;
+		report_size = MIN(USB_MAX_PACKET_SIZE, report_left);
+		memcpy_to_usbram((void *) usb_sram_addr(ep0_buf_tx),
+				 report_ptr, report_size);
+		btable_ep[0].tx_count = report_size;
+		report_left -= report_size;
+		report_ptr += report_size;
+		STM32_TOGGLE_EP(0, EP_TX_MASK, EP_TX_VALID,
+				report_left ? 0 : EP_STATUS_OUT);
+		return report_left ? 1 : 0;
+	} else if ((ep0_buf_rx[0] == (USB_DIR_IN | USB_RECIP_INTERFACE |
 			      (USB_REQ_GET_DESCRIPTOR << 8))) &&
 			      (ep0_buf_rx[1] == (USB_HID_DT_REPORT << 8))) {
 		/* Setup : HID specific : Get Report descriptor */
+		report_size = MIN(ep0_buf_rx[3], report_size);
+
+		if (report_size > USB_MAX_PACKET_SIZE) {
+			/* Report descriptor does not fit in one packet. */
+			report_left = report_size - USB_MAX_PACKET_SIZE;
+			report_ptr = report_desc + USB_MAX_PACKET_SIZE;
+			report_size = USB_MAX_PACKET_SIZE;
+		} else {
+			report_left = 0;
+		}
 		memcpy_to_usbram((void *) usb_sram_addr(ep0_buf_tx),
-				 report_desc,
-				 report_size);
-		btable_ep[0].tx_count = MIN(ep0_buf_rx[3], report_size);
+				 report_desc, report_size);
+		btable_ep[0].tx_count = report_size;
 		STM32_TOGGLE_EP(0, EP_TX_RX_MASK, EP_TX_RX_VALID,
-			  EP_STATUS_OUT);
-		CPRINTF("RPT %04x[l %04x]\n", STM32_USB_EP(0),
-			ep0_buf_rx[3]);
-		return 0;
+				report_left ? 0 : EP_STATUS_OUT);
+		return report_left ? 1 : 0;
 	}
 
-	return 1;
+	return -1;
 }