diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-07 19:23:21 -0800 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-02-07 19:23:21 -0800 |
commit | c96e2c92072d3e78954c961f53d8c7352f7abbd7 (patch) | |
tree | d844f26f926ff40e98e9eae0e11fd71acad81df4 /drivers/usb/host/uhci-hcd.c | |
parent | f2aca47dc3c2d0c2d5dbd972558557e74232bbce (diff) | |
parent | 64358164f5bfe5e11d4040c1eb674c29e1436ce5 (diff) |
Merge master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/gregkh/usb-2.6: (70 commits)
USB: remove duplicate device id from zc0301
USB: remove duplicate device id from usb_storage
USB: remove duplicate device id from keyspan
USB: remove duplicate device id from ftdi_sio
USB: remove duplicate device id from visor
USB: a bit more coding style cleanup
usbcore: trivial whitespace fixes
usb-storage: use first bulk endpoints, not last
EHCI: fix interrupt-driven remote wakeup
USB: switch ehci-hcd to new polling scheme
USB: autosuspend for usb printer driver
USB Input: Added kernel module to support all GTCO CalComp USB InterWrite School products
USB: Sierra Wireless auto set D0
USB: usb ethernet gadget recognizes HUSB2DEV
USB: list atmel husb2_udc gadget controller
USB: gadgetfs AIO tweaks
USB: gadgetfs behaves better on userspace init bug
USB: gadgetfs race fix
USB: gadgetfs simplifications
USB: gadgetfs cleanups
...
Diffstat (limited to 'drivers/usb/host/uhci-hcd.c')
-rw-r--r-- | drivers/usb/host/uhci-hcd.c | 51 |
1 files changed, 29 insertions, 22 deletions
diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c index e0d4c2358b39..49b9d390b95f 100644 --- a/drivers/usb/host/uhci-hcd.c +++ b/drivers/usb/host/uhci-hcd.c @@ -92,6 +92,34 @@ static void suspend_rh(struct uhci_hcd *uhci, enum uhci_rh_state new_state); static void wakeup_rh(struct uhci_hcd *uhci); static void uhci_get_current_frame_number(struct uhci_hcd *uhci); +/* + * Calculate the link pointer DMA value for the first Skeleton QH in a frame. + */ +static __le32 uhci_frame_skel_link(struct uhci_hcd *uhci, int frame) +{ + int skelnum; + + /* + * The interrupt queues will be interleaved as evenly as possible. + * There's not much to be done about period-1 interrupts; they have + * to occur in every frame. But we can schedule period-2 interrupts + * in odd-numbered frames, period-4 interrupts in frames congruent + * to 2 (mod 4), and so on. This way each frame only has two + * interrupt QHs, which will help spread out bandwidth utilization. + * + * ffs (Find First bit Set) does exactly what we need: + * 1,3,5,... => ffs = 0 => use skel_int2_qh = skelqh[8], + * 2,6,10,... => ffs = 1 => use skel_int4_qh = skelqh[7], etc. + * ffs >= 7 => not on any high-period queue, so use + * skel_int1_qh = skelqh[9]. + * Add in UHCI_NUMFRAMES to insure at least one bit is set. + */ + skelnum = 8 - (int) __ffs(frame | UHCI_NUMFRAMES); + if (skelnum <= 1) + skelnum = 9; + return UHCI_PTR_QH | cpu_to_le32(uhci->skelqh[skelnum]->dma_handle); +} + #include "uhci-debug.c" #include "uhci-q.c" #include "uhci-hub.c" @@ -631,32 +659,11 @@ static int uhci_start(struct usb_hcd *hcd) /* * Fill the frame list: make all entries point to the proper * interrupt queue. - * - * The interrupt queues will be interleaved as evenly as possible. - * There's not much to be done about period-1 interrupts; they have - * to occur in every frame. But we can schedule period-2 interrupts - * in odd-numbered frames, period-4 interrupts in frames congruent - * to 2 (mod 4), and so on. This way each frame only has two - * interrupt QHs, which will help spread out bandwidth utilization. */ for (i = 0; i < UHCI_NUMFRAMES; i++) { - int irq; - - /* - * ffs (Find First bit Set) does exactly what we need: - * 1,3,5,... => ffs = 0 => use skel_int2_qh = skelqh[8], - * 2,6,10,... => ffs = 1 => use skel_int4_qh = skelqh[7], etc. - * ffs >= 7 => not on any high-period queue, so use - * skel_int1_qh = skelqh[9]. - * Add UHCI_NUMFRAMES to insure at least one bit is set. - */ - irq = 8 - (int) __ffs(i + UHCI_NUMFRAMES); - if (irq <= 1) - irq = 9; /* Only place we don't use the frame list routines */ - uhci->frame[i] = UHCI_PTR_QH | - cpu_to_le32(uhci->skelqh[irq]->dma_handle); + uhci->frame[i] = uhci_frame_skel_link(uhci, i); } /* |