electronics
/
libopencm3
9
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

usb: Support for class specific endpoint descriptors. 

Extends struct usb_endpoint_descriptor to make it possible to provide
the USB host with class-specific extensions to endpoint descriptors.

The approach taken, based on extra and extralen and removing the sizeof()
from USB_DT_ENDPOINT_SIZE, is identical to the approach used to add
class-specific extensions to interface descriptors. All libopencm3-examples
use the USB_DT_ENDPOINT_SIZE (rather than directly using sizeof) so there
should be no compatibility problems resulting from this change.
This commit is contained in:
Daniel Thompson 2014-12-03 08:18:21 +00:00 committed by Karl Palsson
parent 0b63408260
commit d3aa579e0a
2 changed files with 14 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/libopencm3/usb/usbstd.h
View File

@ -205,8 +205,12 @@ struct usb_endpoint_descriptor {
uint8_t bmAttributes;
uint16_t wMaxPacketSize;
uint8_t bInterval;
/* Descriptor ends here. The following are used internally: */
const void *extra;
int extralen;
} __attribute__((packed));
#define USB_DT_ENDPOINT_SIZE sizeof(struct usb_endpoint_descriptor)
#define USB_DT_ENDPOINT_SIZE 7
/* USB Endpoint Descriptor bmAttributes bit definitions */
#define USB_ENDPOINT_ATTR_CONTROL 0x00

9
lib/usb/usb_standard.c
View File

@ -110,6 +110,15 @@ static uint16_t build_config_descriptor(usbd_device *usbd_dev,
len -= count;
total += count;
totallen += ep->bLength;
/* Copy extra bytes (class specific). */
if (ep->extra) {
memcpy(buf, ep->extra,
count = MIN(len, ep->extralen));
buf += count;
len -= count;
total += count;
totallen += ep->extralen;
}
}
}
}