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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-17 22:24:26 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-17 22:24:26 +0100
commit48d10bda1f2c69980601a61194015bb0790fb7ab (patch)
treee4ea2021560b1f18b335f6e8e20761fb9514cd1b /drivers/usb/host/ehci-q.c
parentMerge tag 'tty-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/greg... (diff)
parentMerge tag 'usb-serial-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/g... (diff)
downloadlinux-48d10bda1f2c69980601a61194015bb0790fb7ab.tar.xz
linux-48d10bda1f2c69980601a61194015bb0790fb7ab.zip
Merge tag 'usb-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH: "Here is the big USB patchset for 4.6-rc1. The normal mess is here, gadget and xhci fixes and updates, and lots of other driver updates and cleanups as well. Full details are in the shortlog. All have been in linux-next for a while with no reported issues" * tag 'usb-4.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (266 commits) USB: core: let USB device know device node usb: devio: Add ioctl to disallow detaching kernel USB drivers. usb: gadget: f_acm: Fix configfs attr name usb: udc: lpc32xx: remove USB PLL and USB OTG clock management usb: udc: lpc32xx: remove direct access to clock controller registers usb: udc: lpc32xx: switch to clock prepare/unprepare model usb: renesas_usbhs: gadget: fix giveback status code in usbhsg_pipe_disable() usb: gadget: renesas_usb3: Use ARCH_RENESAS usb: dwc2: Fix issues in dwc2_complete_non_isoc_xfer_ddma() usb: dwc2: Add support for Lantiq ARX and XRX SoCs usb: phy: generic: Handle late registration of gadget usb: gadget: bdc_udc: fix race condition in bdc_udc_exit() usb: musb: core: added missing const qualifier to musb_hdrc_platform_data::config usb: dwc2: Move host-specific core functions into hcd.c usb: dwc2: Move register save and restore functions usb: dwc2: Use kmem_cache_free() usb: dwc2: host: If using uframe scheduler, end splits better usb: dwc2: host: Totally redo the microframe scheduler usb: dwc2: host: Properly set even/odd frame usb: dwc2: host: Add dwc2_hcd_get_future_frame_number() call ...
Diffstat (limited to 'drivers/usb/host/ehci-q.c')
-rw-r--r--drivers/usb/host/ehci-q.c104
1 files changed, 80 insertions, 24 deletions
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index aad0777240d3..eca3710d8fc4 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -394,6 +394,7 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh)
goto retry_xacterr;
}
stopped = 1;
+ qh->unlink_reason |= QH_UNLINK_HALTED;
/* magic dummy for some short reads; qh won't advance.
* that silicon quirk can kick in with this dummy too.
@@ -408,6 +409,7 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh)
&& !(qtd->hw_alt_next
& EHCI_LIST_END(ehci))) {
stopped = 1;
+ qh->unlink_reason |= QH_UNLINK_SHORT_READ;
}
/* stop scanning when we reach qtds the hc is using */
@@ -420,8 +422,10 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh)
stopped = 1;
/* cancel everything if we halt, suspend, etc */
- if (ehci->rh_state < EHCI_RH_RUNNING)
+ if (ehci->rh_state < EHCI_RH_RUNNING) {
last_status = -ESHUTDOWN;
+ qh->unlink_reason |= QH_UNLINK_SHUTDOWN;
+ }
/* this qtd is active; skip it unless a previous qtd
* for its urb faulted, or its urb was canceled.
@@ -538,10 +542,10 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh)
* except maybe high bandwidth ...
*/
if (stopped != 0 || hw->hw_qtd_next == EHCI_LIST_END(ehci))
- qh->exception = 1;
+ qh->unlink_reason |= QH_UNLINK_DUMMY_OVERLAY;
/* Let the caller know if the QH needs to be unlinked. */
- return qh->exception;
+ return qh->unlink_reason;
}
/*-------------------------------------------------------------------------*/
@@ -1003,7 +1007,7 @@ static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh)
qh->qh_state = QH_STATE_LINKED;
qh->xacterrs = 0;
- qh->exception = 0;
+ qh->unlink_reason = 0;
/* qtd completions reported later by interrupt */
enable_async(ehci);
@@ -1279,17 +1283,13 @@ static void single_unlink_async(struct ehci_hcd *ehci, struct ehci_qh *qh)
static void start_iaa_cycle(struct ehci_hcd *ehci)
{
- /* Do nothing if an IAA cycle is already running */
- if (ehci->iaa_in_progress)
- return;
- ehci->iaa_in_progress = true;
-
/* If the controller isn't running, we don't have to wait for it */
if (unlikely(ehci->rh_state < EHCI_RH_RUNNING)) {
end_unlink_async(ehci);
- /* Otherwise start a new IAA cycle */
- } else if (likely(ehci->rh_state == EHCI_RH_RUNNING)) {
+ /* Otherwise start a new IAA cycle if one isn't already running */
+ } else if (ehci->rh_state == EHCI_RH_RUNNING &&
+ !ehci->iaa_in_progress) {
/* Make sure the unlinks are all visible to the hardware */
wmb();
@@ -1297,17 +1297,13 @@ static void start_iaa_cycle(struct ehci_hcd *ehci)
ehci_writel(ehci, ehci->command | CMD_IAAD,
&ehci->regs->command);
ehci_readl(ehci, &ehci->regs->command);
+ ehci->iaa_in_progress = true;
ehci_enable_event(ehci, EHCI_HRTIMER_IAA_WATCHDOG, true);
}
}
-/* the async qh for the qtds being unlinked are now gone from the HC */
-
-static void end_unlink_async(struct ehci_hcd *ehci)
+static void end_iaa_cycle(struct ehci_hcd *ehci)
{
- struct ehci_qh *qh;
- bool early_exit;
-
if (ehci->has_synopsys_hc_bug)
ehci_writel(ehci, (u32) ehci->async->qh_dma,
&ehci->regs->async_next);
@@ -1315,6 +1311,16 @@ static void end_unlink_async(struct ehci_hcd *ehci)
/* The current IAA cycle has ended */
ehci->iaa_in_progress = false;
+ end_unlink_async(ehci);
+}
+
+/* See if the async qh for the qtds being unlinked are now gone from the HC */
+
+static void end_unlink_async(struct ehci_hcd *ehci)
+{
+ struct ehci_qh *qh;
+ bool early_exit;
+
if (list_empty(&ehci->async_unlink))
return;
qh = list_first_entry(&ehci->async_unlink, struct ehci_qh,
@@ -1335,14 +1341,60 @@ static void end_unlink_async(struct ehci_hcd *ehci)
* after the IAA interrupt occurs. In self-defense, always go
* through two IAA cycles for each QH.
*/
- else if (qh->qh_state == QH_STATE_UNLINK_WAIT) {
+ else if (qh->qh_state == QH_STATE_UNLINK) {
+ /*
+ * Second IAA cycle has finished. Process only the first
+ * waiting QH (NVIDIA (?) bug).
+ */
+ list_move_tail(&qh->unlink_node, &ehci->async_idle);
+ }
+
+ /*
+ * AMD/ATI (?) bug: The HC can continue to use an active QH long
+ * after the IAA interrupt occurs. To prevent problems, QHs that
+ * may still be active will wait until 2 ms have passed with no
+ * change to the hw_current and hw_token fields (this delay occurs
+ * between the two IAA cycles).
+ *
+ * The EHCI spec (4.8.2) says that active QHs must not be removed
+ * from the async schedule and recommends waiting until the QH
+ * goes inactive. This is ridiculous because the QH will _never_
+ * become inactive if the endpoint NAKs indefinitely.
+ */
+
+ /* Some reasons for unlinking guarantee the QH can't be active */
+ else if (qh->unlink_reason & (QH_UNLINK_HALTED |
+ QH_UNLINK_SHORT_READ | QH_UNLINK_DUMMY_OVERLAY))
+ goto DelayDone;
+
+ /* The QH can't be active if the queue was and still is empty... */
+ else if ((qh->unlink_reason & QH_UNLINK_QUEUE_EMPTY) &&
+ list_empty(&qh->qtd_list))
+ goto DelayDone;
+
+ /* ... or if the QH has halted */
+ else if (qh->hw->hw_token & cpu_to_hc32(ehci, QTD_STS_HALT))
+ goto DelayDone;
+
+ /* Otherwise we have to wait until the QH stops changing */
+ else {
+ __hc32 qh_current, qh_token;
+
+ qh_current = qh->hw->hw_current;
+ qh_token = qh->hw->hw_token;
+ if (qh_current != ehci->old_current ||
+ qh_token != ehci->old_token) {
+ ehci->old_current = qh_current;
+ ehci->old_token = qh_token;
+ ehci_enable_event(ehci,
+ EHCI_HRTIMER_ACTIVE_UNLINK, true);
+ return;
+ }
+ DelayDone:
qh->qh_state = QH_STATE_UNLINK;
early_exit = true;
}
-
- /* Otherwise process only the first waiting QH (NVIDIA bug?) */
- else
- list_move_tail(&qh->unlink_node, &ehci->async_idle);
+ ehci->old_current = ~0; /* Prepare for next QH */
/* Start a new IAA cycle if any QHs are waiting for it */
if (!list_empty(&ehci->async_unlink))
@@ -1395,6 +1447,7 @@ static void unlink_empty_async(struct ehci_hcd *ehci)
/* If nothing else is being unlinked, unlink the last empty QH */
if (list_empty(&ehci->async_unlink) && qh_to_unlink) {
+ qh_to_unlink->unlink_reason |= QH_UNLINK_QUEUE_EMPTY;
start_unlink_async(ehci, qh_to_unlink);
--count;
}
@@ -1406,8 +1459,10 @@ static void unlink_empty_async(struct ehci_hcd *ehci)
}
}
+#ifdef CONFIG_PM
+
/* The root hub is suspended; unlink all the async QHs */
-static void __maybe_unused unlink_empty_async_suspended(struct ehci_hcd *ehci)
+static void unlink_empty_async_suspended(struct ehci_hcd *ehci)
{
struct ehci_qh *qh;
@@ -1416,9 +1471,10 @@ static void __maybe_unused unlink_empty_async_suspended(struct ehci_hcd *ehci)
WARN_ON(!list_empty(&qh->qtd_list));
single_unlink_async(ehci, qh);
}
- start_iaa_cycle(ehci);
}
+#endif
+
/* makes sure the async qh will become idle */
/* caller must own ehci->lock */