update(class/hid/usbh_hid): export usbh_hid_get_report_descriptor api, issue #260

Author: sakumisu

class/hid/usbh_hid.c

@@ -50,10 +50,9 @@ static void usbh_hid_class_free(struct usbh_hid *hid_class)
     memset(hid_class, 0, sizeof(struct usbh_hid));
 }
 
-static int usbh_hid_get_report_descriptor(struct usbh_hid *hid_class, uint8_t *buffer)
+int usbh_hid_get_report_descriptor(struct usbh_hid *hid_class, uint8_t *buffer, uint32_t buflen)
 {
     struct usb_setup_packet *setup;
-    int ret;
 
     if (!hid_class || !hid_class->hport) {
         return -USB_ERR_INVAL;
@@ -64,14 +63,9 @@ static int usbh_hid_get_report_descriptor(struct usbh_hid *hid_class, uint8_t *b
     setup->bRequest = USB_REQUEST_GET_DESCRIPTOR;
     setup->wValue = HID_DESCRIPTOR_TYPE_HID_REPORT << 8;
     setup->wIndex = hid_class->intf;
-    setup->wLength = hid_class->report_size;
+    setup->wLength = buflen;
 
-    ret = usbh_control_transfer(hid_class->hport, setup, g_hid_buf[hid_class->minor]);
-    if (ret < 8) {
-        return ret;
-    }
-    memcpy(buffer, g_hid_buf[hid_class->minor], ret - 8);
-    return ret;
+    return usbh_control_transfer(hid_class->hport, setup, buffer);
 }
 
 int usbh_hid_set_idle(struct usbh_hid *hid_class, uint8_t report_id, uint8_t duration)
@@ -215,11 +209,6 @@ int usbh_hid_connect(struct usbh_hubport *hport, uint8_t intf)
                     }
 
                     hid_class->report_size = desc->subdesc[0].wDescriptorLength;
-
-                    if (hid_class->report_size > sizeof(g_hid_buf[hid_class->minor])) {
-                        USB_LOG_ERR("HID report descriptor too large\r\n");
-                        return -USB_ERR_INVAL;
-                    }
                     found = true;
                     goto found;
                 }
@@ -247,7 +236,8 @@ int usbh_hid_connect(struct usbh_hubport *hport, uint8_t intf)
         USB_LOG_WRN("Do not support set idle\r\n");
     }
 
-    ret = usbh_hid_get_report_descriptor(hid_class, hid_class->report_desc);
+    /* We read report desc but do nothing (because of too much memory usage for parsing report desc, parsed by users) */
+    ret = usbh_hid_get_report_descriptor(hid_class, g_hid_buf[hid_class->minor], MIN(sizeof(g_hid_buf[hid_class->minor]), hid_class->report_size));
     if (ret < 0) {
         return ret;
     }

class/hid/usbh_hid.h

@@ -15,7 +15,6 @@ struct usbh_hid {
     struct usbh_urb intin_urb;              /* INTR IN urb */
     struct usbh_urb intout_urb;             /* INTR OUT urb */
 
-    uint8_t report_desc[256];
     uint16_t report_size;
 
     uint8_t protocol;
@@ -29,6 +28,7 @@ struct usbh_hid {
 extern "C" {
 #endif
 
+int usbh_hid_get_report_descriptor(struct usbh_hid *hid_class, uint8_t *buffer, uint32_t buflen);
 int usbh_hid_set_idle(struct usbh_hid *hid_class, uint8_t report_id, uint8_t duration);
 int usbh_hid_get_idle(struct usbh_hid *hid_class, uint8_t *buffer);
 int usbh_hid_set_report(struct usbh_hid *hid_class, uint8_t report_type, uint8_t report_id, uint8_t *buffer, uint32_t buflen);