svn commit: r208012 - in head: lib/libusbhid sys/dev/usb

[Andrew Thompson]

Author: thompsa
Date: Wed May 12 22:50:23 2010
New Revision: 208012
URL: http://svn.freebsd.org/changeset/base/208012

Log:
  Support getting signed and unsigned HID data.
  
  Submitted by:	Alex Deiter
  Reviewed by:	Hans Petter Selaksy

Modified:
  head/lib/libusbhid/data.c
  head/sys/dev/usb/usb_hid.c
  head/sys/dev/usb/usbhid.h

Modified: head/lib/libusbhid/data.c
==============================================================================
--- head/lib/libusbhid/data.c	Wed May 12 22:45:44 2010	(r208011)
+++ head/lib/libusbhid/data.c	Wed May 12 22:50:23 2010	(r208012)
@@ -63,13 +63,17 @@ hid_get_data(const void *p, const hid_it
 	data = 0;
 	for (i = 0; i <= end; i++)
 		data |= buf[offs + i] << (i*8);
+
+	/* Correctly shift down data */
 	data >>= hpos % 8;
-	data &= (1 << hsize) - 1;
-	if (h->logical_minimum < 0) {
-		/* Need to sign extend */
-		hsize = sizeof data * 8 - hsize;
-		data = (data << hsize) >> hsize;
-	}
+	hsize = 32 - hsize;
+
+	/* Mask and sign extend in one */
+	if ((h->logical_minimum < 0) || (h->logical_maximum < 0))
+		data = (int32_t)((int32_t)data << hsize) >> hsize;
+	else
+		data = (uint32_t)((uint32_t)data << hsize) >> hsize;
+
 	return (data);
 }
 

Modified: head/sys/dev/usb/usb_hid.c
==============================================================================
--- head/sys/dev/usb/usb_hid.c	Wed May 12 22:45:44 2010	(r208011)
+++ head/sys/dev/usb/usb_hid.c	Wed May 12 22:50:23 2010	(r208012)
@@ -646,8 +646,9 @@ hid_locate(const void *desc, usb_size_t 
 /*------------------------------------------------------------------------*
  *	hid_get_data
  *------------------------------------------------------------------------*/
-uint32_t
-hid_get_data(const uint8_t *buf, usb_size_t len, struct hid_location *loc)
+static uint32_t
+hid_get_data_sub(const uint8_t *buf, usb_size_t len, struct hid_location *loc,
+    int is_signed)
 {
 	uint32_t hpos = loc->pos;
 	uint32_t hsize = loc->size;
@@ -676,16 +677,31 @@ hid_get_data(const uint8_t *buf, usb_siz
 
 	/* Correctly shift down data */
 	data = (data >> (hpos % 8));
+	n = 32 - hsize;
 
 	/* Mask and sign extend in one */
-	n = 32 - hsize;
-	data = ((int32_t)data << n) >> n;
+	if (is_signed != 0)
+		data = (int32_t)((int32_t)data << n) >> n;
+	else
+		data = (uint32_t)((uint32_t)data << n) >> n;
 
 	DPRINTFN(11, "hid_get_data: loc %d/%d = %lu\n",
 	    loc->pos, loc->size, (long)data);
 	return (data);
 }
 
+int32_t
+hid_get_data(const uint8_t *buf, usb_size_t len, struct hid_location *loc)
+{
+	return (hid_get_data_sub(buf, len, loc, 1));
+}
+
+uint32_t
+hid_get_data_unsigned(const uint8_t *buf, usb_size_t len, struct hid_location *loc)
+{
+        return (hid_get_data_sub(buf, len, loc, 0));
+}
+
 /*------------------------------------------------------------------------*
  *	hid_is_collection
  *------------------------------------------------------------------------*/

Modified: head/sys/dev/usb/usbhid.h
==============================================================================
--- head/sys/dev/usb/usbhid.h	Wed May 12 22:45:44 2010	(r208011)
+++ head/sys/dev/usb/usbhid.h	Wed May 12 22:50:23 2010	(r208012)
@@ -229,7 +229,9 @@ int	hid_report_size(const void *buf, usb
 int	hid_locate(const void *desc, usb_size_t size, uint32_t usage,
 	    enum hid_kind kind, uint8_t index, struct hid_location *loc,
 	    uint32_t *flags, uint8_t *id);
-uint32_t hid_get_data(const uint8_t *buf, usb_size_t len,
+int32_t hid_get_data(const uint8_t *buf, usb_size_t len,
+	    struct hid_location *loc);
+uint32_t hid_get_data_unsigned(const uint8_t *buf, usb_size_t len,
 	    struct hid_location *loc);
 int	hid_is_collection(const void *desc, usb_size_t size, uint32_t usage);
 struct usb_hid_descriptor *hid_get_descriptor_from_usb(