linux/drivers/usb/host/uhci-hub.c
Alan Stern b446b96fd1 UHCI: hub_status_data should indicate if ports are resuming
This patch (as1538) causes uhci_hub_status_data() to return a nonzero
value when any port is undergoing a resume transition while the root
hub is suspended.  This will allow usbcore to handle races between
root-hub suspend and port wakeup.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-04-09 15:43:21 -07:00

414 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 const __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)
/* suspend/resume bits: port suspended or port resuming */
#define SUSPEND_BITS (USBPORTSC_SUSP | USBPORTSC_RD)
/* 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 ((uhci_readw(uhci, 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 ((uhci_readw(uhci, 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 = uhci_readw(uhci, port_addr); \
status &= ~(RWC_BITS|WZ_BITS); \
status &= ~(x); \
status |= RWC_BITS & (x); \
uhci_writew(uhci, status, port_addr)
#define SET_RH_PORTSTAT(x) \
status = uhci_readw(uhci, port_addr); \
status |= (x); \
status &= ~(RWC_BITS|WZ_BITS); \
uhci_writew(uhci, 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 (uhci_readw(uhci, port_addr) & SUSPEND_BITS) {
CLR_RH_PORTSTAT(SUSPEND_BITS);
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 (!(uhci_readw(uhci, port_addr) & SUSPEND_BITS))
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(struct uhci_hcd *uhci, unsigned long port_addr)
{
int i;
for (i = 10; i < 250; i += 10) {
if (uhci_readw(uhci, 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 = USBPORTSC1 + 2 * port;
status = uhci_readw(uhci, 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 (uhci->wait_for_hp)
wait_for_HP(uhci, 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(25);
/* 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 (!HCD_HW_ACCESSIBLE(hcd) || uhci->dead)
goto done;
uhci_check_ports(uhci);
status = get_hub_status_data(uhci, buf);
switch (uhci->rh_state) {
case UHCI_RH_SUSPENDED:
/* if port change, ask to be resumed */
if (status || uhci->resuming_ports) {
status = 1;
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 = USBPORTSC1 + 2 * port;
u16 wPortChange, wPortStatus;
unsigned long flags;
if (!HCD_HW_ACCESSIBLE(hcd) || 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 = uhci_readw(uhci, 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 (uhci->oc_low)
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 & SUSPEND_BITS)
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 (!(uhci_readw(uhci, 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 (!(uhci_readw(uhci, 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;
}