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[PATCH] USB: fix in usb_calc_bus_time

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This patch does the same swap, i.e. use the ISO macro if (isoc).
Additionally, it fixes the return value - the usb_calc_bus_time function
returns the time in nanoseconds (I didn't notice that before) while the
HS_USECS and HS_USECS_ISO are microseconds.  This fixes the function to
return nanoseconds always, and adjusts ehci-q.c (the only high-speed
caller of the function) to wrap the call in NS_TO_US().

Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Dan Streetman
2005-07-29 12:18:28 -07:00
committed by Linus Torvalds
parent 6b216df87c
commit 498f78e6fc
3 changed files with 9 additions and 7 deletions
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8
drivers/usb/core/hcd.h
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@ -334,17 +334,19 @@ extern void usb_release_bandwidth (struct usb_device *dev, struct urb *urb,
extern int usb_check_bandwidth (struct usb_device *dev, struct urb *urb);
/*
* Ceiling microseconds (typical) for that many bytes at high speed
* Ceiling [nano/micro]seconds (typical) for that many bytes at high speed
* ISO is a bit less, no ACK ... from USB 2.0 spec, 5.11.3 (and needed
* to preallocate bandwidth)
*/
#define USB2_HOST_DELAY 5 /* nsec, guess */
#define HS_USECS(bytes) NS_TO_US ( ((55 * 8 * 2083)/1000) \
#define HS_NSECS(bytes) ( ((55 * 8 * 2083)/1000) \
+ ((2083UL * (3167 + BitTime (bytes)))/1000) \
+ USB2_HOST_DELAY)
#define HS_USECS_ISO(bytes) NS_TO_US ( ((38 * 8 * 2083)/1000) \
#define HS_NSECS_ISO(bytes) ( ((38 * 8 * 2083)/1000) \
+ ((2083UL * (3167 + BitTime (bytes)))/1000) \
+ USB2_HOST_DELAY)
#define HS_USECS(bytes) NS_TO_US (HS_NSECS(bytes))
#define HS_USECS_ISO(bytes) NS_TO_US (HS_NSECS_ISO(bytes))
extern long usb_calc_bus_time (int speed, int is_input,
int isoc, int bytecount);