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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-02-07 19:23:21 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-02-07 19:23:21 -0800
commitc96e2c92072d3e78954c961f53d8c7352f7abbd7 (patch)
treed844f26f926ff40e98e9eae0e11fd71acad81df4 /drivers/usb/host/uhci-hcd.c
parentf2aca47dc3c2d0c2d5dbd972558557e74232bbce (diff)
parent64358164f5bfe5e11d4040c1eb674c29e1436ce5 (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.c51
1 files changed, 29 insertions, 22 deletions
diff --git a/drivers/usb/host/uhci-hcd.c b/drivers/usb/host/uhci-hcd.c
index e0d4c2358b3..49b9d390b95 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);
}
/*