1/* ehci-lpm.c EHCI HCD LPM support code
 2 * Copyright (c) 2008 - 2010,  Intel Corporation.
 3 * Author: Jacob Pan <jacob.jun.pan@intel.com>
 4 *
 5 * This program is free software; you can redistribute it and/or modify
 6 * it under the terms of the GNU General Public License version 2 as
 7 * published by the Free Software Foundation.
 8 *
 9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
17*/
18
19/* this file is part of ehci-hcd.c */
20static int __maybe_unused ehci_lpm_set_da(struct ehci_hcd *ehci,
21	int dev_addr, int port_num)
22{
23	u32 __iomem portsc;
24
25	ehci_dbg(ehci, "set dev address %d for port %d\n", dev_addr, port_num);
26	if (port_num > HCS_N_PORTS(ehci->hcs_params)) {
27		ehci_dbg(ehci, "invalid port number %d\n", port_num);
28		return -ENODEV;
29	}
30	portsc = ehci_readl(ehci, &ehci->regs->port_status[port_num-1]);
31	portsc &= ~PORT_DEV_ADDR;
32	portsc |= dev_addr<<25;
33	ehci_writel(ehci, portsc, &ehci->regs->port_status[port_num-1]);
34	return 0;
35}
36
37/*
38 * this function is used to check if the device support LPM
39 * if yes, mark the PORTSC register with PORT_LPM bit
40 */
41static int __maybe_unused ehci_lpm_check(struct ehci_hcd *ehci, int port)
42{
43	u32 __iomem	*portsc ;
44	u32 val32;
45	int retval;
46
47	portsc = &ehci->regs->port_status[port-1];
48	val32 = ehci_readl(ehci, portsc);
49	if (!(val32 & PORT_DEV_ADDR)) {
50		ehci_dbg(ehci, "LPM: no device attached\n");
51		return -ENODEV;
52	}
53	val32 |= PORT_LPM;
54	ehci_writel(ehci, val32, portsc);
55	msleep(5);
56	val32 |= PORT_SUSPEND;
57	ehci_dbg(ehci, "Sending LPM 0x%08x to port %d\n", val32, port);
58	ehci_writel(ehci, val32, portsc);
59	/* wait for ACK */
60	msleep(10);
61	retval = handshake(ehci, &ehci->regs->port_status[port-1], PORT_SSTS,
62			PORTSC_SUSPEND_STS_ACK, 125);
63	dbg_port(ehci, "LPM", port, val32);
64	if (retval != -ETIMEDOUT) {
65		ehci_dbg(ehci, "LPM: device ACK for LPM\n");
66		val32 |= PORT_LPM;
67		/*
68		 * now device should be in L1 sleep, let's wake up the device
69		 * so that we can complete enumeration.
70		 */
71		ehci_writel(ehci, val32, portsc);
72		msleep(10);
73		val32 |= PORT_RESUME;
74		ehci_writel(ehci, val32, portsc);
75	} else {
76		ehci_dbg(ehci, "LPM: device does not ACK, disable LPM %d\n",
77			retval);
78		val32 &= ~PORT_LPM;
79		retval = -ETIMEDOUT;
80		ehci_writel(ehci, val32, portsc);
81	}
82
83	return retval;
84}