David,
I was hoping to get your feedback on how you would like to handle an
errata that Freescale has in their EHCI controllers. Their multiport host
controller has the following errata:
"Port number in the Queue head is 0 to N-1. It should be 1 to N according
to EHCI spec. This bug only affects the host mode."
Would something like the following patch be acceptable? If so, I'll
follow up with a proper patch that includes the detection and setting of
has_fsl_port_bug.
- kumar
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index 9b13bf2..711597b 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -721,7 +721,14 @@ qh_make (
info1 |= maxp << 16;
info2 |= (EHCI_TUNE_MULT_TT << 30);
- info2 |= urb->dev->ttport << 23;
+
+ /* Some Freescale processors have an errata in which the
+ * port number in the queue head was 0..N-1 instead of 1..N.
+ */
+ if (ehci_has_FSL_portno_bug(ehci))
+ info2 |= (urb->dev->ttport-1) << 23;
+ else
+ info2 |= urb->dev->ttport << 23;
/* set the address of the TT; for TDI's integrated
* root hub tt, leave it zeroed.
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 18e257c..d180488 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -89,6 +89,8 @@ struct ehci_hcd { /* one per controlle
u32 command;
unsigned is_tdi_rh_tt:1; /* TDI roothub with TT */
+ /* FSL controller with port number errata */
+ unsigned has_fsl_port_bug:1;
/* irq statistics */
#ifdef EHCI_STATS
@@ -638,6 +640,18 @@ ehci_port_speed(struct ehci_hcd *ehci, u
/*-------------------------------------------------------------------------*/
+#ifdef CONFIG_PPC_83xx
+/* Some Freescale processors have an errata in which the
+ * port number in the queue head was 0..N-1 instead of 1..N.
+ */
+#define ehci_has_FSL_portno_bug(e) ((e)->has_fsl_port_bug)
+#else
+#define ehci_has_FSL_portno_bug(e) (0)
+#endif
+
+
+/*-------------------------------------------------------------------------*/
+
#ifndef DEBUG
#define STUB_DEBUG_FILES
#endif /* DEBUG */
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