bartoszek/zephyr
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

include: usb_ch9: fix USB_FS_ISO_EP_INTERVAL calculation

Browse Source 
Per section 5.6.4 of the USB 2.0 standard, Isochronous Endpoints
are derived by the (2^(bInterval-1) * F) formula. The current
implementation uses the formula intended for Interrupt Endpoints.

Signed-off-by: Victor Brzeski <vbrzeski@gmail.com>
This commit is contained in:
Victor Brzeski 2025-06-24 21:47:06 -07:00 committed by Dan Kalowsky
parent 48dc588636
commit d9c7b19ae0
1 changed files with 2 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
include/zephyr/usb/usb_ch9.h
View File

@ -354,8 +354,8 @@ struct usb_association_descriptor {
/** Calculate high speed interrupt endpoint bInterval from a value in microseconds */
#define USB_HS_INT_EP_INTERVAL(us) CLAMP((ilog2((us) / 125U) + 1U), 1U, 16U)
/** Calculate high speed isochronous endpoint bInterval from a value in microseconds */
#define USB_FS_ISO_EP_INTERVAL(us) CLAMP(((us) / 1000U), 1U, 16U)
/** Calculate full speed isochronous endpoint bInterval from a value in microseconds */
#define USB_FS_ISO_EP_INTERVAL(us) CLAMP((ilog2((us) / 1000U) + 1U), 1U, 16U)
/** Calculate high speed isochronous endpoint bInterval from a value in microseconds */
#define USB_HS_ISO_EP_INTERVAL(us) CLAMP((ilog2((us) / 125U) + 1U), 1U, 16U)