From: Alek Du <alek.du@xxxxxxxxx>
With this patch, the LPM capable EHCI host controller can put device
into L1 sleep state which is a mode that can enter/exit quickly, and
reduce power consumption.
Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxx>
Signed-off-by: Alek Du <alek.du@xxxxxxxxx>
---
drivers/usb/core/hub.c | 4 ++-
drivers/usb/host/ehci-hcd.c | 17 +++++++++
drivers/usb/host/ehci-hub.c | 5 +++
drivers/usb/host/ehci-lpm.c | 83 +++++++++++++++++++++++++++++++++++++++++++
drivers/usb/host/ehci-pci.c | 21 +++++++++++
drivers/usb/host/ehci.h | 2 +-
include/linux/usb/hcd.h | 4 ++
7 files changed, 134 insertions(+), 2 deletions(-)
create mode 100644 drivers/usb/host/ehci-lpm.c
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c
index 83e7bbb..6592fc8 100644
--- a/drivers/usb/core/hub.c
+++ b/drivers/usb/core/hub.c
@@ -2878,7 +2878,9 @@ hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
}
retval = 0;
-
+ /* notify HCD that we have a device connected and addressed */
+ if (hcd->driver->update_device)
+ hcd->driver->update_device(hcd, udev);
fail:
if (retval) {
hub_port_disable(hub, port1, 0);
diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index ef3e88f..69e1361 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -100,6 +100,11 @@ static int ignore_oc = 0;
module_param (ignore_oc, bool, S_IRUGO);
MODULE_PARM_DESC (ignore_oc, "ignore bogus hardware overcurrent indications");
+/* for link power management(LPM) feature */
+static unsigned int hird;
+module_param(hird, int, S_IRUGO);
+MODULE_PARM_DESC(hird, "host initiated resume duration, +1 for each 75us\n");
+
#define INTR_MASK (STS_IAA | STS_FATAL | STS_PCD | STS_ERR | STS_INT)
/*-------------------------------------------------------------------------*/
@@ -304,6 +309,7 @@ static void end_unlink_async(struct ehci_hcd *ehci);
static void ehci_work(struct ehci_hcd *ehci);
#include "ehci-hub.c"
+#include "ehci-lpm.c"
#include "ehci-mem.c"
#include "ehci-q.c"
#include "ehci-sched.c"
@@ -603,6 +609,17 @@ static int ehci_init(struct usb_hcd *hcd)
default: BUG();
}
}
+ if (HCC_LPM(hcc_params)) {
+ /* support link power management EHCI 1.1 addendum */
+ ehci_dbg(ehci, "support lpm\n");
+ ehci->has_lpm = 1;
+ if (hird > 0xf) {
+ ehci_dbg(ehci, "hird %d invalid, use default 0",
+ hird);
+ hird = 0;
+ }
+ temp |= hird << 24;
+ }
ehci->command = temp;
/* Accept arbitrarily long scatter-gather lists */
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c
index e7d3d8d..8a28dae 100644
--- a/drivers/usb/host/ehci-hub.c
+++ b/drivers/usb/host/ehci-hub.c
@@ -790,6 +790,11 @@ static int ehci_hub_control (
status_reg);
break;
case USB_PORT_FEAT_C_CONNECTION:
+ if (ehci->has_lpm) {
+ /* clear PORTSC bits on disconnect */
+ temp &= ~PORT_LPM;
+ temp &= ~PORT_DEV_ADDR;
+ }
ehci_writel(ehci, (temp & ~PORT_RWC_BITS) | PORT_CSC,
status_reg);
break;
diff --git a/drivers/usb/host/ehci-lpm.c b/drivers/usb/host/ehci-lpm.c
new file mode 100644
index 0000000..b4d4d63
--- /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@xxxxxxxxx>
+ *
+ * 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;
+}
diff --git a/drivers/usb/host/ehci-pci.c b/drivers/usb/host/ehci-pci.c
index d43d176..a307d55 100644
--- a/drivers/usb/host/ehci-pci.c
+++ b/drivers/usb/host/ehci-pci.c
@@ -361,6 +361,22 @@ static int ehci_pci_resume(struct usb_hcd *hcd, bool hibernated)
}
#endif
+static int ehci_update_device(struct usb_hcd *hcd, struct usb_device *udev)
+{
+ struct ehci_hcd *ehci = hcd_to_ehci(hcd);
+ int rc = 0;
+
+ if (!udev->parent) /* udev is root hub itself, impossible */
+ rc = -1;
+ /* we only support lpm device connected to root hub yet */
+ if (ehci->has_lpm && !udev->parent->parent) {
+ rc = ehci_lpm_set_da(ehci, udev->devnum, udev->portnum);
+ if (!rc)
+ rc = ehci_lpm_check(ehci, udev->portnum);
+ }
+ return rc;
+}
+
static const struct hc_driver ehci_pci_hc_driver = {
.description = hcd_name,
.product_desc = "EHCI Host Controller",
@@ -407,6 +423,11 @@ static const struct hc_driver ehci_pci_hc_driver = {
.relinquish_port = ehci_relinquish_port,
.port_handed_over = ehci_port_handed_over,
+ /*
+ * call back when device connected and addressed
+ */
+ .update_device = ehci_update_device,
+
.clear_tt_buffer_complete = ehci_clear_tt_buffer_complete,
};
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index bfaac16..21f30a0 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -140,7 +140,7 @@ struct ehci_hcd { /* one per controller */
#define OHCI_HCCTRL_LEN 0x4
__hc32 *ohci_hcctrl_reg;
unsigned has_hostpc:1;
-
+ unsigned has_lpm:1; /* support link power management */
u8 sbrn; /* packed release number */
/* irq statistics */
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index 2e3a4ea..ed1a148 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -299,6 +299,10 @@ struct hc_driver {
int (*update_hub_device)(struct usb_hcd *, struct usb_device *hdev,
struct usb_tt *tt, gfp_t mem_flags);
int (*reset_device)(struct usb_hcd *, struct usb_device *);
+ /* Notifies the HCD after a device is connected and its
+ * address is set
+ */
+ int (*update_device)(struct usb_hcd *, struct usb_device *);
};
extern int usb_hcd_link_urb_to_ep(struct usb_hcd *hcd, struct urb *urb);
--
1.7.0.4
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