From 5a9cdf332eae724b11906cb1712e3a662eba32b2 Mon Sep 17 00:00:00 2001 From: Alek Du Date: Fri, 4 Jun 2010 15:47:56 +0800 Subject: [PATCH] USB: EHCI: EHCI 1.1 addendum: Enable Per-port change detect bits This patch will enable Per-port event feature defined in EHCI 1.1 addendum. This feature addresses an issue where HCD is currently required to read and parse PORTSC for all enabled root hub ports. With this patch, the overhead will be reduced. Signed-off-by: Alek Du Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-hcd.c | 19 +++++++++++++++++-- drivers/usb/host/ehci-hub.c | 9 +++++++++ drivers/usb/host/ehci.h | 1 + 3 files changed, 27 insertions(+), 2 deletions(-) diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c index baf9b648bb1..8697ad19f31 100644 --- a/drivers/usb/host/ehci-hcd.c +++ b/drivers/usb/host/ehci-hcd.c @@ -584,6 +584,11 @@ static int ehci_init(struct usb_hcd *hcd) if (log2_irq_thresh < 0 || log2_irq_thresh > 6) log2_irq_thresh = 0; temp = 1 << (16 + log2_irq_thresh); + if (HCC_PER_PORT_CHANGE_EVENT(hcc_params)) { + ehci->has_ppcd = 1; + ehci_dbg(ehci, "enable per-port change event\n"); + temp |= CMD_PPCEE; + } if (HCC_CANPARK(hcc_params)) { /* HW default park == 3, on hardware that supports it (like * NVidia and ALI silicon), maximizes throughput on the async @@ -782,6 +787,7 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd) /* remote wakeup [4.3.1] */ if (status & STS_PCD) { unsigned i = HCS_N_PORTS (ehci->hcs_params); + u32 ppcd = 0; /* kick root hub later */ pcd_status = status; @@ -790,9 +796,18 @@ static irqreturn_t ehci_irq (struct usb_hcd *hcd) if (!(cmd & CMD_RUN)) usb_hcd_resume_root_hub(hcd); + /* get per-port change detect bits */ + if (ehci->has_ppcd) + ppcd = status >> 16; + while (i--) { - int pstatus = ehci_readl(ehci, - &ehci->regs->port_status [i]); + int pstatus; + + /* leverage per-port change bits feature */ + if (ehci->has_ppcd && !(ppcd & (1 << i))) + continue; + pstatus = ehci_readl(ehci, + &ehci->regs->port_status[i]); if (pstatus & PORT_OWNER) continue; diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index 8a28dae8a37..84e792d71c2 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -603,6 +603,7 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf) u32 mask; int ports, i, retval = 1; unsigned long flags; + u32 ppcd = 0; /* if !USB_SUSPEND, root hub timers won't get shut down ... */ if (!HC_IS_RUNNING(hcd->state)) @@ -632,7 +633,15 @@ ehci_hub_status_data (struct usb_hcd *hcd, char *buf) /* port N changes (bit N)? */ spin_lock_irqsave (&ehci->lock, flags); + + /* get per-port change detect bits */ + if (ehci->has_ppcd) + ppcd = ehci_readl(ehci, &ehci->regs->status) >> 16; + for (i = 0; i < ports; i++) { + /* leverage per-port change bits feature */ + if (ehci->has_ppcd && !(ppcd & (1 << i))) + continue; temp = ehci_readl(ehci, &ehci->regs->port_status [i]); /* diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h index 21f30a0c3d2..e6c57cc416f 100644 --- a/drivers/usb/host/ehci.h +++ b/drivers/usb/host/ehci.h @@ -141,6 +141,7 @@ struct ehci_hcd { /* one per controller */ __hc32 *ohci_hcctrl_reg; unsigned has_hostpc:1; unsigned has_lpm:1; /* support link power management */ + unsigned has_ppcd:1; /* support per-port change bits */ u8 sbrn; /* packed release number */ /* irq statistics */ -- 2.46.0