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linux-next/drivers/usb/host/uhci-hub.c
Alan Stern 5f8364b7d6 UHCI: module parameter to ignore overcurrent changes
Certain boards seem to like to issue false overcurrent notifications,
for example on ports that don't have anything connected to them.  This
looks like a hardware error, at the level of noise to those ports'
overcurrent input signals (or non-debounced VBUS comparators).  This
surfaces to users as truly massive amounts of syslog spam from khubd
(which is appropriate for real hardware problems, except for the
volume from multiple ports).

Using this new "ignore_oc" flag helps such systems work more sanely,
by preventing such indications from getting to khubd (and spamming
syslog).  The downside is of course that true overcurrent errors will
be masked; they'll appear as spontaneous disconnects, without the
diagnostics that will let users troubleshoot issues like
short-circuited cables.  In addition, controllers with no devices
attached will be forced to poll for new devices rather than relying on
interrupts, since each overcurrent event would generate a new
interrupt.

This patch (as826) is essentially a copy of David Brownell's ignore_oc
patch for ehci-hcd, ported to uhci-hcd.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-12-20 10:14:26 -08:00

412 lines
11 KiB
C

/*
* Universal Host Controller Interface driver for USB.
*
* Maintainer: Alan Stern <stern@rowland.harvard.edu>
*
* (C) Copyright 1999 Linus Torvalds
* (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com
* (C) Copyright 1999 Randy Dunlap
* (C) Copyright 1999 Georg Acher, acher@in.tum.de
* (C) Copyright 1999 Deti Fliegl, deti@fliegl.de
* (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch
* (C) Copyright 2004 Alan Stern, stern@rowland.harvard.edu
*/
static __u8 root_hub_hub_des[] =
{
0x09, /* __u8 bLength; */
0x29, /* __u8 bDescriptorType; Hub-descriptor */
0x02, /* __u8 bNbrPorts; */
0x0a, /* __u16 wHubCharacteristics; */
0x00, /* (per-port OC, no power switching) */
0x01, /* __u8 bPwrOn2pwrGood; 2ms */
0x00, /* __u8 bHubContrCurrent; 0 mA */
0x00, /* __u8 DeviceRemovable; *** 7 Ports max *** */
0xff /* __u8 PortPwrCtrlMask; *** 7 ports max *** */
};
#define UHCI_RH_MAXCHILD 7
/* must write as zeroes */
#define WZ_BITS (USBPORTSC_RES2 | USBPORTSC_RES3 | USBPORTSC_RES4)
/* status change bits: nonzero writes will clear */
#define RWC_BITS (USBPORTSC_OCC | USBPORTSC_PEC | USBPORTSC_CSC)
/* A port that either is connected or has a changed-bit set will prevent
* us from AUTO_STOPPING.
*/
static int any_ports_active(struct uhci_hcd *uhci)
{
int port;
for (port = 0; port < uhci->rh_numports; ++port) {
if ((inw(uhci->io_addr + USBPORTSC1 + port * 2) &
(USBPORTSC_CCS | RWC_BITS)) ||
test_bit(port, &uhci->port_c_suspend))
return 1;
}
return 0;
}
static inline int get_hub_status_data(struct uhci_hcd *uhci, char *buf)
{
int port;
int mask = RWC_BITS;
/* Some boards (both VIA and Intel apparently) report bogus
* overcurrent indications, causing massive log spam unless
* we completely ignore them. This doesn't seem to be a problem
* with the chipset so much as with the way it is connected on
* the motherboard; if the overcurrent input is left to float
* then it may constantly register false positives. */
if (ignore_oc)
mask &= ~USBPORTSC_OCC;
*buf = 0;
for (port = 0; port < uhci->rh_numports; ++port) {
if ((inw(uhci->io_addr + USBPORTSC1 + port * 2) & mask) ||
test_bit(port, &uhci->port_c_suspend))
*buf |= (1 << (port + 1));
}
return !!*buf;
}
#define OK(x) len = (x); break
#define CLR_RH_PORTSTAT(x) \
status = inw(port_addr); \
status &= ~(RWC_BITS|WZ_BITS); \
status &= ~(x); \
status |= RWC_BITS & (x); \
outw(status, port_addr)
#define SET_RH_PORTSTAT(x) \
status = inw(port_addr); \
status |= (x); \
status &= ~(RWC_BITS|WZ_BITS); \
outw(status, port_addr)
/* UHCI controllers don't automatically stop resume signalling after 20 msec,
* so we have to poll and check timeouts in order to take care of it.
*/
static void uhci_finish_suspend(struct uhci_hcd *uhci, int port,
unsigned long port_addr)
{
int status;
int i;
if (inw(port_addr) & (USBPORTSC_SUSP | USBPORTSC_RD)) {
CLR_RH_PORTSTAT(USBPORTSC_SUSP | USBPORTSC_RD);
if (test_bit(port, &uhci->resuming_ports))
set_bit(port, &uhci->port_c_suspend);
/* The controller won't actually turn off the RD bit until
* it has had a chance to send a low-speed EOP sequence,
* which is supposed to take 3 bit times (= 2 microseconds).
* Experiments show that some controllers take longer, so
* we'll poll for completion. */
for (i = 0; i < 10; ++i) {
if (!(inw(port_addr) & USBPORTSC_RD))
break;
udelay(1);
}
}
clear_bit(port, &uhci->resuming_ports);
}
/* Wait for the UHCI controller in HP's iLO2 server management chip.
* It can take up to 250 us to finish a reset and set the CSC bit.
*/
static void wait_for_HP(unsigned long port_addr)
{
int i;
for (i = 10; i < 250; i += 10) {
if (inw(port_addr) & USBPORTSC_CSC)
return;
udelay(10);
}
/* Log a warning? */
}
static void uhci_check_ports(struct uhci_hcd *uhci)
{
unsigned int port;
unsigned long port_addr;
int status;
for (port = 0; port < uhci->rh_numports; ++port) {
port_addr = uhci->io_addr + USBPORTSC1 + 2 * port;
status = inw(port_addr);
if (unlikely(status & USBPORTSC_PR)) {
if (time_after_eq(jiffies, uhci->ports_timeout)) {
CLR_RH_PORTSTAT(USBPORTSC_PR);
udelay(10);
/* HP's server management chip requires
* a longer delay. */
if (to_pci_dev(uhci_dev(uhci))->vendor ==
PCI_VENDOR_ID_HP)
wait_for_HP(port_addr);
/* If the port was enabled before, turning
* reset on caused a port enable change.
* Turning reset off causes a port connect
* status change. Clear these changes. */
CLR_RH_PORTSTAT(USBPORTSC_CSC | USBPORTSC_PEC);
SET_RH_PORTSTAT(USBPORTSC_PE);
}
}
if (unlikely(status & USBPORTSC_RD)) {
if (!test_bit(port, &uhci->resuming_ports)) {
/* Port received a wakeup request */
set_bit(port, &uhci->resuming_ports);
uhci->ports_timeout = jiffies +
msecs_to_jiffies(20);
/* Make sure we see the port again
* after the resuming period is over. */
mod_timer(&uhci_to_hcd(uhci)->rh_timer,
uhci->ports_timeout);
} else if (time_after_eq(jiffies,
uhci->ports_timeout)) {
uhci_finish_suspend(uhci, port, port_addr);
}
}
}
}
static int uhci_hub_status_data(struct usb_hcd *hcd, char *buf)
{
struct uhci_hcd *uhci = hcd_to_uhci(hcd);
unsigned long flags;
int status = 0;
spin_lock_irqsave(&uhci->lock, flags);
uhci_scan_schedule(uhci);
if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) || uhci->dead)
goto done;
uhci_check_ports(uhci);
status = get_hub_status_data(uhci, buf);
switch (uhci->rh_state) {
case UHCI_RH_SUSPENDING:
case UHCI_RH_SUSPENDED:
/* if port change, ask to be resumed */
if (status)
usb_hcd_resume_root_hub(hcd);
break;
case UHCI_RH_AUTO_STOPPED:
/* if port change, auto start */
if (status)
wakeup_rh(uhci);
break;
case UHCI_RH_RUNNING:
/* are any devices attached? */
if (!any_ports_active(uhci)) {
uhci->rh_state = UHCI_RH_RUNNING_NODEVS;
uhci->auto_stop_time = jiffies + HZ;
}
break;
case UHCI_RH_RUNNING_NODEVS:
/* auto-stop if nothing connected for 1 second */
if (any_ports_active(uhci))
uhci->rh_state = UHCI_RH_RUNNING;
else if (time_after_eq(jiffies, uhci->auto_stop_time))
suspend_rh(uhci, UHCI_RH_AUTO_STOPPED);
break;
default:
break;
}
done:
spin_unlock_irqrestore(&uhci->lock, flags);
return status;
}
/* size of returned buffer is part of USB spec */
static int uhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
u16 wIndex, char *buf, u16 wLength)
{
struct uhci_hcd *uhci = hcd_to_uhci(hcd);
int status, lstatus, retval = 0, len = 0;
unsigned int port = wIndex - 1;
unsigned long port_addr = uhci->io_addr + USBPORTSC1 + 2 * port;
u16 wPortChange, wPortStatus;
unsigned long flags;
if (!test_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags) || uhci->dead)
return -ETIMEDOUT;
spin_lock_irqsave(&uhci->lock, flags);
switch (typeReq) {
case GetHubStatus:
*(__le32 *)buf = cpu_to_le32(0);
OK(4); /* hub power */
case GetPortStatus:
if (port >= uhci->rh_numports)
goto err;
uhci_check_ports(uhci);
status = inw(port_addr);
/* Intel controllers report the OverCurrent bit active on.
* VIA controllers report it active off, so we'll adjust the
* bit value. (It's not standardized in the UHCI spec.)
*/
if (to_pci_dev(hcd->self.controller)->vendor ==
PCI_VENDOR_ID_VIA)
status ^= USBPORTSC_OC;
/* UHCI doesn't support C_RESET (always false) */
wPortChange = lstatus = 0;
if (status & USBPORTSC_CSC)
wPortChange |= USB_PORT_STAT_C_CONNECTION;
if (status & USBPORTSC_PEC)
wPortChange |= USB_PORT_STAT_C_ENABLE;
if ((status & USBPORTSC_OCC) && !ignore_oc)
wPortChange |= USB_PORT_STAT_C_OVERCURRENT;
if (test_bit(port, &uhci->port_c_suspend)) {
wPortChange |= USB_PORT_STAT_C_SUSPEND;
lstatus |= 1;
}
if (test_bit(port, &uhci->resuming_ports))
lstatus |= 4;
/* UHCI has no power switching (always on) */
wPortStatus = USB_PORT_STAT_POWER;
if (status & USBPORTSC_CCS)
wPortStatus |= USB_PORT_STAT_CONNECTION;
if (status & USBPORTSC_PE) {
wPortStatus |= USB_PORT_STAT_ENABLE;
if (status & (USBPORTSC_SUSP | USBPORTSC_RD))
wPortStatus |= USB_PORT_STAT_SUSPEND;
}
if (status & USBPORTSC_OC)
wPortStatus |= USB_PORT_STAT_OVERCURRENT;
if (status & USBPORTSC_PR)
wPortStatus |= USB_PORT_STAT_RESET;
if (status & USBPORTSC_LSDA)
wPortStatus |= USB_PORT_STAT_LOW_SPEED;
if (wPortChange)
dev_dbg(uhci_dev(uhci), "port %d portsc %04x,%02x\n",
wIndex, status, lstatus);
*(__le16 *)buf = cpu_to_le16(wPortStatus);
*(__le16 *)(buf + 2) = cpu_to_le16(wPortChange);
OK(4);
case SetHubFeature: /* We don't implement these */
case ClearHubFeature:
switch (wValue) {
case C_HUB_OVER_CURRENT:
case C_HUB_LOCAL_POWER:
OK(0);
default:
goto err;
}
break;
case SetPortFeature:
if (port >= uhci->rh_numports)
goto err;
switch (wValue) {
case USB_PORT_FEAT_SUSPEND:
SET_RH_PORTSTAT(USBPORTSC_SUSP);
OK(0);
case USB_PORT_FEAT_RESET:
SET_RH_PORTSTAT(USBPORTSC_PR);
/* Reset terminates Resume signalling */
uhci_finish_suspend(uhci, port, port_addr);
/* USB v2.0 7.1.7.5 */
uhci->ports_timeout = jiffies + msecs_to_jiffies(50);
OK(0);
case USB_PORT_FEAT_POWER:
/* UHCI has no power switching */
OK(0);
default:
goto err;
}
break;
case ClearPortFeature:
if (port >= uhci->rh_numports)
goto err;
switch (wValue) {
case USB_PORT_FEAT_ENABLE:
CLR_RH_PORTSTAT(USBPORTSC_PE);
/* Disable terminates Resume signalling */
uhci_finish_suspend(uhci, port, port_addr);
OK(0);
case USB_PORT_FEAT_C_ENABLE:
CLR_RH_PORTSTAT(USBPORTSC_PEC);
OK(0);
case USB_PORT_FEAT_SUSPEND:
if (!(inw(port_addr) & USBPORTSC_SUSP)) {
/* Make certain the port isn't suspended */
uhci_finish_suspend(uhci, port, port_addr);
} else if (!test_and_set_bit(port,
&uhci->resuming_ports)) {
SET_RH_PORTSTAT(USBPORTSC_RD);
/* The controller won't allow RD to be set
* if the port is disabled. When this happens
* just skip the Resume signalling.
*/
if (!(inw(port_addr) & USBPORTSC_RD))
uhci_finish_suspend(uhci, port,
port_addr);
else
/* USB v2.0 7.1.7.7 */
uhci->ports_timeout = jiffies +
msecs_to_jiffies(20);
}
OK(0);
case USB_PORT_FEAT_C_SUSPEND:
clear_bit(port, &uhci->port_c_suspend);
OK(0);
case USB_PORT_FEAT_POWER:
/* UHCI has no power switching */
goto err;
case USB_PORT_FEAT_C_CONNECTION:
CLR_RH_PORTSTAT(USBPORTSC_CSC);
OK(0);
case USB_PORT_FEAT_C_OVER_CURRENT:
CLR_RH_PORTSTAT(USBPORTSC_OCC);
OK(0);
case USB_PORT_FEAT_C_RESET:
/* this driver won't report these */
OK(0);
default:
goto err;
}
break;
case GetHubDescriptor:
len = min_t(unsigned int, sizeof(root_hub_hub_des), wLength);
memcpy(buf, root_hub_hub_des, len);
if (len > 2)
buf[2] = uhci->rh_numports;
OK(len);
default:
err:
retval = -EPIPE;
}
spin_unlock_irqrestore(&uhci->lock, flags);
return retval;
}