diff options
Diffstat (limited to 'drivers/usb/host/ehci-lpm.c')
| -rw-r--r-- | drivers/usb/host/ehci-lpm.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-lpm.c b/drivers/usb/host/ehci-lpm.c new file mode 100644 index 000000000000..b4d4d63c13ed --- /dev/null +++ b/drivers/usb/host/ehci-lpm.c @@ -0,0 +1,83 @@ +/* ehci-lpm.c EHCI HCD LPM support code + * Copyright (c) 2008 - 2010, Intel Corporation. + * Author: Jacob Pan <jacob.jun.pan@intel.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. +*/ + +/* this file is part of ehci-hcd.c */ +static int ehci_lpm_set_da(struct ehci_hcd *ehci, int dev_addr, int port_num) +{ + u32 __iomem portsc; + + ehci_dbg(ehci, "set dev address %d for port %d\n", dev_addr, port_num); + if (port_num > HCS_N_PORTS(ehci->hcs_params)) { + ehci_dbg(ehci, "invalid port number %d\n", port_num); + return -ENODEV; + } + portsc = ehci_readl(ehci, &ehci->regs->port_status[port_num-1]); + portsc &= ~PORT_DEV_ADDR; + portsc |= dev_addr<<25; + ehci_writel(ehci, portsc, &ehci->regs->port_status[port_num-1]); + return 0; +} + +/* + * this function is used to check if the device support LPM + * if yes, mark the PORTSC register with PORT_LPM bit + */ +static int ehci_lpm_check(struct ehci_hcd *ehci, int port) +{ + u32 __iomem *portsc ; + u32 val32; + int retval; + + portsc = &ehci->regs->port_status[port-1]; + val32 = ehci_readl(ehci, portsc); + if (!(val32 & PORT_DEV_ADDR)) { + ehci_dbg(ehci, "LPM: no device attached\n"); + return -ENODEV; + } + val32 |= PORT_LPM; + ehci_writel(ehci, val32, portsc); + msleep(5); + val32 |= PORT_SUSPEND; + ehci_dbg(ehci, "Sending LPM 0x%08x to port %d\n", val32, port); + ehci_writel(ehci, val32, portsc); + /* wait for ACK */ + msleep(10); + retval = handshake(ehci, &ehci->regs->port_status[port-1], PORT_SSTS, + PORTSC_SUSPEND_STS_ACK, 125); + dbg_port(ehci, "LPM", port, val32); + if (retval != -ETIMEDOUT) { + ehci_dbg(ehci, "LPM: device ACK for LPM\n"); + val32 |= PORT_LPM; + /* + * now device should be in L1 sleep, let's wake up the device + * so that we can complete enumeration. + */ + ehci_writel(ehci, val32, portsc); + msleep(10); + val32 |= PORT_RESUME; + ehci_writel(ehci, val32, portsc); + } else { + ehci_dbg(ehci, "LPM: device does not ACK, disable LPM %d\n", + retval); + val32 &= ~PORT_LPM; + retval = -ETIMEDOUT; + ehci_writel(ehci, val32, portsc); + } + + return retval; +} |