/* 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 __maybe_unused 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 __maybe_unused 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;
}
