From: david-b@pacbell.net Date: Fri, 12 Aug 2005 02:37:01 +0000 (-0700) Subject: [PATCH] USB: tweak highspeed timing calculations X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=f956e7cd9ac4618b98022020e638bbdc01d9d65a;p=deliverable%2Flinux.git [PATCH] USB: tweak highspeed timing calculations Use a more correct calculation for highspeed bit times. http://bugzilla.kernel.org/show_bug.cgi?id=3604 This sort if thing might start to make a difference now that the high speed periodic scheduler is more complete -- and even getting used. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/core/hcd.h b/drivers/usb/core/hcd.h index 28055f95645b..ac451fa7e4d2 100644 --- a/drivers/usb/core/hcd.h +++ b/drivers/usb/core/hcd.h @@ -339,11 +339,11 @@ extern int usb_check_bandwidth (struct usb_device *dev, struct urb *urb); * to preallocate bandwidth) */ #define USB2_HOST_DELAY 5 /* nsec, guess */ -#define HS_NSECS(bytes) ( ((55 * 8 * 2083)/1000) \ - + ((2083UL * (3167 + BitTime (bytes)))/1000) \ +#define HS_NSECS(bytes) ( ((55 * 8 * 2083) \ + + (2083UL * (3 + BitTime(bytes))))/1000 \ + USB2_HOST_DELAY) -#define HS_NSECS_ISO(bytes) ( ((38 * 8 * 2083)/1000) \ - + ((2083UL * (3167 + BitTime (bytes)))/1000) \ +#define HS_NSECS_ISO(bytes) ( ((38 * 8 * 2083) \ + + (2083UL * (3 + 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))