[PATCH] USB: EHCI port tweaks
One change may improve some S1 or S3 resume cases, and the other
seems mostly to explain some strange state "lsusb" would show.
Two fixes:
- On resume, don't think about resuming any unpowered port, or
resetting any port with OWNER set to the OHCI/UHCI companion.
This will make some S1 and S3 resume scenarios work better.
- PORT_CSC was not being cleared correctly in ehci_hub_status_data.
This was visible at least through current versions of "lsusb",
and might have caused some other hub related strangeness.
The fix addresses all three write-to-clear bits, using the same
approach that UHCI happens to use: a mask of bits that are
cleared in most writes to that port status register.
Original patch seems to have been from from William.Morrow@amd.com
and this version (from David) finishes the write-to-clear changes.
Signed-off-by: Jordan Crouse <jordan.crouse@amd.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 2507e89..2f7037c 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -759,12 +759,16 @@
if (time_before (jiffies, ehci->next_statechange))
msleep (100);
- /* If any port is suspended, we know we can/must resume the HC. */
+ /* If any port is suspended (or owned by the companion),
+ * we know we can/must resume the HC (and mustn't reset it).
+ */
for (port = HCS_N_PORTS (ehci->hcs_params); port > 0; ) {
u32 status;
port--;
status = readl (&ehci->regs->port_status [port]);
- if (status & PORT_SUSPEND) {
+ if (!(status & PORT_POWER))
+ continue;
+ if (status & (PORT_SUSPEND | PORT_OWNER)) {
down (&hcd->self.root_hub->serialize);
retval = ehci_hub_resume (hcd);
up (&hcd->self.root_hub->serialize);
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index 36cc1f2..18d3f22 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -54,7 +54,7 @@
/* suspend any active/unsuspended ports, maybe allow wakeup */
while (port--) {
u32 __iomem *reg = &ehci->regs->port_status [port];
- u32 t1 = readl (reg);
+ u32 t1 = readl (reg) & ~PORT_RWC_BITS;
u32 t2 = t1;
if ((t1 & PORT_PE) && !(t1 & PORT_OWNER))
@@ -115,7 +115,8 @@
i = HCS_N_PORTS (ehci->hcs_params);
while (i--) {
temp = readl (&ehci->regs->port_status [i]);
- temp &= ~(PORT_WKOC_E|PORT_WKDISC_E|PORT_WKCONN_E);
+ temp &= ~(PORT_RWC_BITS
+ | PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E);
if (temp & PORT_SUSPEND) {
ehci->reset_done [i] = jiffies + msecs_to_jiffies (20);
temp |= PORT_RESUME;
@@ -128,7 +129,7 @@
temp = readl (&ehci->regs->port_status [i]);
if ((temp & PORT_SUSPEND) == 0)
continue;
- temp &= ~PORT_RESUME;
+ temp &= ~(PORT_RWC_BITS | PORT_RESUME);
writel (temp, &ehci->regs->port_status [i]);
ehci_vdbg (ehci, "resumed port %d\n", i + 1);
}
@@ -191,6 +192,7 @@
// what happens if HCS_N_CC(params) == 0 ?
port_status |= PORT_OWNER;
+ port_status &= ~PORT_RWC_BITS;
writel (port_status, &ehci->regs->port_status [index]);
} else
@@ -233,7 +235,8 @@
if (temp & PORT_OWNER) {
/* don't report this in GetPortStatus */
if (temp & PORT_CSC) {
- temp &= ~PORT_CSC;
+ temp &= ~PORT_RWC_BITS;
+ temp |= PORT_CSC;
writel (temp, &ehci->regs->port_status [i]);
}
continue;
@@ -343,7 +346,7 @@
&ehci->regs->port_status [wIndex]);
break;
case USB_PORT_FEAT_C_ENABLE:
- writel (temp | PORT_PEC,
+ writel((temp & ~PORT_RWC_BITS) | PORT_PEC,
&ehci->regs->port_status [wIndex]);
break;
case USB_PORT_FEAT_SUSPEND:
@@ -353,7 +356,8 @@
if ((temp & PORT_PE) == 0)
goto error;
/* resume signaling for 20 msec */
- writel ((temp & ~PORT_WAKE_BITS) | PORT_RESUME,
+ temp &= ~(PORT_RWC_BITS | PORT_WAKE_BITS);
+ writel (temp | PORT_RESUME,
&ehci->regs->port_status [wIndex]);
ehci->reset_done [wIndex] = jiffies
+ msecs_to_jiffies (20);
@@ -364,15 +368,15 @@
break;
case USB_PORT_FEAT_POWER:
if (HCS_PPC (ehci->hcs_params))
- writel (temp & ~PORT_POWER,
+ writel (temp & ~(PORT_RWC_BITS | PORT_POWER),
&ehci->regs->port_status [wIndex]);
break;
case USB_PORT_FEAT_C_CONNECTION:
- writel (temp | PORT_CSC,
+ writel((temp & ~PORT_RWC_BITS) | PORT_CSC,
&ehci->regs->port_status [wIndex]);
break;
case USB_PORT_FEAT_C_OVER_CURRENT:
- writel (temp | PORT_OCC,
+ writel((temp & ~PORT_RWC_BITS) | PORT_OCC,
&ehci->regs->port_status [wIndex]);
break;
case USB_PORT_FEAT_C_RESET:
@@ -416,7 +420,7 @@
/* stop resume signaling */
temp = readl (&ehci->regs->port_status [wIndex]);
- writel (temp & ~PORT_RESUME,
+ writel (temp & ~(PORT_RWC_BITS | PORT_RESUME),
&ehci->regs->port_status [wIndex]);
retval = handshake (
&ehci->regs->port_status [wIndex],
@@ -437,7 +441,7 @@
ehci->reset_done [wIndex] = 0;
/* force reset to complete */
- writel (temp & ~PORT_RESET,
+ writel (temp & ~(PORT_RWC_BITS | PORT_RESET),
&ehci->regs->port_status [wIndex]);
/* REVISIT: some hardware needs 550+ usec to clear
* this bit; seems too long to spin routinely...
@@ -500,6 +504,7 @@
if (temp & PORT_OWNER)
break;
+ temp &= ~PORT_RWC_BITS;
switch (wValue) {
case USB_PORT_FEAT_SUSPEND:
if ((temp & PORT_PE) == 0
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 20c9b55..f34a051 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -263,6 +263,7 @@
#define PORT_PE (1<<2) /* port enable */
#define PORT_CSC (1<<1) /* connect status change */
#define PORT_CONNECT (1<<0) /* device connected */
+#define PORT_RWC_BITS (PORT_CSC | PORT_PEC | PORT_OCC)
} __attribute__ ((packed));
/* Appendix C, Debug port ... intended for use with special "debug devices"