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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-08-21 02:38:44 -0400
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-08-21 02:38:44 -0400
commit8eb891fc809b2300137bcd247025628c06c95a63 (patch)
tree5f7da9517835fef971a2f0c8ed69ca86c3f8099d /drivers/usb/host/ehci-hcd.c
parent848c4dd5153c7a0de55470ce99a8e13a63b4703f (diff)
Revert "USB: EHCI cpufreq fix"
This reverts commit 196705c9bbc03540429b0f7cf9ee35c2f928a534. It was reported to cause a regression by Daniel Exner, and Arjan van de Ven points out that we actually already have infrastructure in place for setting limits on acceptable DMA latency that would be the much more correct fix for the problem with some Broadcom EHCI controllers. Fixed up trivial conflicts due to the changes to support big-endian host controller descriptors in drivers/usb/host/{ehci-sched.c,ehci.h}. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/usb/host/ehci-hcd.c')
-rw-r--r--drivers/usb/host/ehci-hcd.c67
1 files changed, 0 insertions, 67 deletions
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index c4e15ed1405a..35cdba10411b 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -275,58 +275,6 @@ static void ehci_work(struct ehci_hcd *ehci);
275 275
276/*-------------------------------------------------------------------------*/ 276/*-------------------------------------------------------------------------*/
277 277
278#ifdef CONFIG_CPU_FREQ
279
280#include <linux/cpufreq.h>
281
282static void ehci_cpufreq_pause (struct ehci_hcd *ehci)
283{
284 unsigned long flags;
285
286 spin_lock_irqsave(&ehci->lock, flags);
287 if (!ehci->cpufreq_changing++)
288 qh_inactivate_split_intr_qhs(ehci);
289 spin_unlock_irqrestore(&ehci->lock, flags);
290}
291
292static void ehci_cpufreq_unpause (struct ehci_hcd *ehci)
293{
294 unsigned long flags;
295
296 spin_lock_irqsave(&ehci->lock, flags);
297 if (!--ehci->cpufreq_changing)
298 qh_reactivate_split_intr_qhs(ehci);
299 spin_unlock_irqrestore(&ehci->lock, flags);
300}
301
302/*
303 * ehci_cpufreq_notifier is needed to avoid MMF errors that occur when
304 * EHCI controllers that don't cache many uframes get delayed trying to
305 * read main memory during CPU frequency transitions. This can cause
306 * split interrupt transactions to not be completed in the required uframe.
307 * This has been observed on the Broadcom/ServerWorks HT1000 controller.
308 */
309static int ehci_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
310 void *data)
311{
312 struct ehci_hcd *ehci = container_of(nb, struct ehci_hcd,
313 cpufreq_transition);
314
315 switch (val) {
316 case CPUFREQ_PRECHANGE:
317 ehci_cpufreq_pause(ehci);
318 break;
319 case CPUFREQ_POSTCHANGE:
320 ehci_cpufreq_unpause(ehci);
321 break;
322 }
323 return 0;
324}
325
326#endif
327
328/*-------------------------------------------------------------------------*/
329
330static void ehci_watchdog (unsigned long param) 278static void ehci_watchdog (unsigned long param)
331{ 279{
332 struct ehci_hcd *ehci = (struct ehci_hcd *) param; 280 struct ehci_hcd *ehci = (struct ehci_hcd *) param;
@@ -460,10 +408,6 @@ static void ehci_stop (struct usb_hcd *hcd)
460 ehci_writel(ehci, 0, &ehci->regs->intr_enable); 408 ehci_writel(ehci, 0, &ehci->regs->intr_enable);
461 spin_unlock_irq(&ehci->lock); 409 spin_unlock_irq(&ehci->lock);
462 410
463#ifdef CONFIG_CPU_FREQ
464 cpufreq_unregister_notifier(&ehci->cpufreq_transition,
465 CPUFREQ_TRANSITION_NOTIFIER);
466#endif
467 /* let companion controllers work when we aren't */ 411 /* let companion controllers work when we aren't */
468 ehci_writel(ehci, 0, &ehci->regs->configured_flag); 412 ehci_writel(ehci, 0, &ehci->regs->configured_flag);
469 413
@@ -569,17 +513,6 @@ static int ehci_init(struct usb_hcd *hcd)
569 } 513 }
570 ehci->command = temp; 514 ehci->command = temp;
571 515
572#ifdef CONFIG_CPU_FREQ
573 INIT_LIST_HEAD(&ehci->split_intr_qhs);
574 /*
575 * If the EHCI controller caches enough uframes, this probably
576 * isn't needed unless there are so many low/full speed devices
577 * that the controller's can't cache it all.
578 */
579 ehci->cpufreq_transition.notifier_call = ehci_cpufreq_notifier;
580 cpufreq_register_notifier(&ehci->cpufreq_transition,
581 CPUFREQ_TRANSITION_NOTIFIER);
582#endif
583 return 0; 516 return 0;
584} 517}
585 518