usb: dwc3-msm: Add support for LPM on cable disconnect
Add runtime power management support in the driver which allows
putting the hardware in low power state, turning off LDOs
and releasing wakelock.
This LPM (aka low power state) support is currently added as part
of USB disconnect and wall-charger connect. LPM support would
later be extended to USB bus suspend as well. Also, support for PHY
retention mode and VDD minimization would be added later.
This commit also adds debugfs nodes that can used to simulate
cable connect and disconnects as A or B device. Following are
the nodes:
-->msm_dwc3/id : Boolean value
-->msm_dwc3/bsv : Boolean value
-->msm_dwc3/connect : can be set to enable/disable
User should first update id/bsv values before enabling 'connect'.
dwc3-msm device is parent of dwc3-core and its runtime PM is managed
by dwc3_otg driver which is responsible for the state transitions
based on notifications from DWC3 h/w or ext_xceiver (using PMIC) for
cable connect and disconnect. This change also allows dwc3 gadget and
host to acquire PM count for the case when dwc3-otg is not present -
e.g. host and device only configurations.
Change-Id: Idd9a59c1ffd46bd98228c9fd4441f668b763534d
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 41f8106..54ea85d 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -522,9 +522,9 @@
if (of_get_property(node, "tx-fifo-resize", NULL))
dwc->needs_fifo_resize = true;
+ pm_runtime_no_callbacks(dev);
+ pm_runtime_set_active(dev);
pm_runtime_enable(dev);
- pm_runtime_get_sync(dev);
- pm_runtime_forbid(dev);
ret = dwc3_core_init(dwc);
if (ret) {
@@ -586,8 +586,6 @@
goto err2;
}
- pm_runtime_allow(dev);
-
return 0;
err2:
@@ -621,7 +619,6 @@
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- pm_runtime_put(&pdev->dev);
pm_runtime_disable(&pdev->dev);
dwc3_debugfs_exit(dwc);
diff --git a/drivers/usb/dwc3/dwc3-msm.c b/drivers/usb/dwc3/dwc3-msm.c
index 05f1a60..136c6d9 100644
--- a/drivers/usb/dwc3/dwc3-msm.c
+++ b/drivers/usb/dwc3/dwc3-msm.c
@@ -16,6 +16,8 @@
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
+#include <linux/pm_runtime.h>
+#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/clk.h>
#include <linux/io.h>
@@ -24,6 +26,8 @@
#include <linux/delay.h>
#include <linux/of.h>
#include <linux/list.h>
+#include <linux/debugfs.h>
+#include <linux/uaccess.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
#include <linux/usb/msm_hsusb.h>
@@ -124,6 +128,12 @@
struct regulator *ssusb_vddcx;
enum usb_vdd_type ss_vdd_type;
enum usb_vdd_type hs_vdd_type;
+ struct dwc3_ext_xceiv ext_xceiv;
+ bool resume_pending;
+ atomic_t pm_suspended;
+ atomic_t in_lpm;
+ struct delayed_work resume_work;
+ struct wake_lock wlock;
struct dwc3_charger charger;
struct usb_phy *otg_xceiv;
struct delayed_work chg_work;
@@ -1213,6 +1223,159 @@
queue_delayed_work(system_nrt_wq, &mdwc->chg_work, 0);
}
+static int dwc3_msm_suspend(struct dwc3_msm *mdwc)
+{
+ dev_dbg(mdwc->dev, "%s: entering lpm\n", __func__);
+
+ if (atomic_read(&mdwc->in_lpm)) {
+ dev_dbg(mdwc->dev, "%s: Already suspended\n", __func__);
+ return 0;
+ }
+
+ clk_disable_unprepare(mdwc->core_clk);
+ dwc3_hsusb_ldo_enable(0);
+ dwc3_ssusb_ldo_enable(0);
+ wake_unlock(&mdwc->wlock);
+
+ atomic_set(&mdwc->in_lpm, 1);
+ dev_info(mdwc->dev, "DWC3 in low power mode\n");
+
+ return 0;
+}
+
+static int dwc3_msm_resume(struct dwc3_msm *mdwc)
+{
+ dev_dbg(mdwc->dev, "%s: exiting lpm\n", __func__);
+
+ if (!atomic_read(&mdwc->in_lpm)) {
+ dev_dbg(mdwc->dev, "%s: Already resumed\n", __func__);
+ return 0;
+ }
+
+ wake_lock(&mdwc->wlock);
+ clk_prepare_enable(mdwc->core_clk);
+ dwc3_hsusb_ldo_enable(1);
+ dwc3_ssusb_ldo_enable(1);
+
+ atomic_set(&mdwc->in_lpm, 0);
+ dev_info(mdwc->dev, "DWC3 exited from low power mode\n");
+
+ return 0;
+}
+
+static void dwc3_resume_work(struct work_struct *w)
+{
+ struct dwc3_msm *mdwc = container_of(w, struct dwc3_msm,
+ resume_work.work);
+
+ dev_dbg(mdwc->dev, "%s: dwc3 resume work\n", __func__);
+ /* handle any event that was queued while work was already running */
+ if (!atomic_read(&mdwc->in_lpm)) {
+ dev_dbg(mdwc->dev, "%s: notifying xceiv event\n", __func__);
+ if (mdwc->otg_xceiv)
+ mdwc->ext_xceiv.notify_ext_events(mdwc->otg_xceiv->otg,
+ DWC3_EVENT_XCEIV_STATE);
+ return;
+ }
+
+ /* bail out if system resume in process, else initiate RESUME */
+ if (atomic_read(&mdwc->pm_suspended)) {
+ mdwc->resume_pending = true;
+ } else {
+ pm_runtime_get_sync(mdwc->dev);
+ if (mdwc->otg_xceiv)
+ mdwc->ext_xceiv.notify_ext_events(mdwc->otg_xceiv->otg,
+ DWC3_EVENT_PHY_RESUME);
+ pm_runtime_put_sync(mdwc->dev);
+ }
+}
+
+static bool debug_id, debug_bsv, debug_connect;
+
+static int dwc3_connect_show(struct seq_file *s, void *unused)
+{
+ if (debug_connect)
+ seq_printf(s, "true\n");
+ else
+ seq_printf(s, "false\n");
+
+ return 0;
+}
+
+static int dwc3_connect_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, dwc3_connect_show, inode->i_private);
+}
+
+static ssize_t dwc3_connect_write(struct file *file, const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ struct seq_file *s = file->private_data;
+ struct dwc3_msm *mdwc = s->private;
+ char buf[8];
+
+ memset(buf, 0x00, sizeof(buf));
+
+ if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
+ return -EFAULT;
+
+ if (!strncmp(buf, "enable", 6) || !strncmp(buf, "true", 4)) {
+ debug_connect = true;
+ } else {
+ debug_connect = debug_bsv = false;
+ debug_id = true;
+ }
+
+ mdwc->ext_xceiv.bsv = debug_bsv;
+ mdwc->ext_xceiv.id = debug_id ? DWC3_ID_FLOAT : DWC3_ID_GROUND;
+
+ if (atomic_read(&mdwc->in_lpm)) {
+ dev_dbg(mdwc->dev, "%s: calling resume_work\n", __func__);
+ dwc3_resume_work(&mdwc->resume_work.work);
+ } else {
+ dev_dbg(mdwc->dev, "%s: notifying xceiv event\n", __func__);
+ if (mdwc->otg_xceiv)
+ mdwc->ext_xceiv.notify_ext_events(mdwc->otg_xceiv->otg,
+ DWC3_EVENT_XCEIV_STATE);
+ }
+
+ return count;
+}
+
+const struct file_operations dwc3_connect_fops = {
+ .open = dwc3_connect_open,
+ .read = seq_read,
+ .write = dwc3_connect_write,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static struct dentry *dwc3_debugfs_root;
+
+static void dwc3_debugfs_init(struct dwc3_msm *mdwc)
+{
+ dwc3_debugfs_root = debugfs_create_dir("msm_dwc3", NULL);
+
+ if (!dwc3_debugfs_root || IS_ERR(dwc3_debugfs_root))
+ return;
+
+ if (!debugfs_create_bool("id", S_IRUGO | S_IWUSR, dwc3_debugfs_root,
+ (u32 *)&debug_id))
+ goto error;
+
+ if (!debugfs_create_bool("bsv", S_IRUGO | S_IWUSR, dwc3_debugfs_root,
+ (u32 *)&debug_bsv))
+ goto error;
+
+ if (!debugfs_create_file("connect", S_IRUGO | S_IWUSR,
+ dwc3_debugfs_root, mdwc, &dwc3_connect_fops))
+ goto error;
+
+ return;
+
+error:
+ debugfs_remove_recursive(dwc3_debugfs_root);
+}
static int __devinit dwc3_msm_probe(struct platform_device *pdev)
{
@@ -1234,6 +1397,7 @@
INIT_LIST_HEAD(&msm->req_complete_list);
INIT_DELAYED_WORK(&msm->chg_work, dwc3_chg_detect_work);
+ INIT_DELAYED_WORK(&msm->resume_work, dwc3_resume_work);
/*
* DWC3 Core requires its CORE CLK (aka master / bus clk) to
@@ -1354,6 +1518,9 @@
msm->resource_size = resource_size(res);
msm->dwc3 = dwc3;
+ pm_runtime_set_active(msm->dev);
+ pm_runtime_enable(msm->dev);
+
if (of_property_read_u32(node, "qcom,dwc-usb3-msm-dbm-eps",
&msm->dbm_num_eps)) {
dev_err(&pdev->dev,
@@ -1395,10 +1562,21 @@
ret);
goto put_xcvr;
}
+
+ ret = dwc3_set_ext_xceiv(msm->otg_xceiv->otg, &msm->ext_xceiv);
+ if (ret || !msm->ext_xceiv.notify_ext_events) {
+ dev_err(&pdev->dev, "failed to register xceiver: %d\n",
+ ret);
+ goto put_xcvr;
+ }
} else {
dev_err(&pdev->dev, "%s: No OTG transceiver found\n", __func__);
}
+ wake_lock_init(&msm->wlock, WAKE_LOCK_SUSPEND, "msm_dwc3");
+ wake_lock(&msm->wlock);
+ dwc3_debugfs_init(msm);
+
return 0;
put_xcvr:
@@ -1432,11 +1610,15 @@
{
struct dwc3_msm *msm = platform_get_drvdata(pdev);
+ if (dwc3_debugfs_root)
+ debugfs_remove_recursive(dwc3_debugfs_root);
if (msm->otg_xceiv) {
dwc3_start_chg_det(&msm->charger, false);
usb_put_transceiver(msm->otg_xceiv);
}
+ pm_runtime_disable(msm->dev);
platform_device_unregister(msm->dwc3);
+ wake_lock_destroy(&msm->wlock);
dwc3_hsusb_ldo_enable(0);
dwc3_hsusb_ldo_init(0);
@@ -1451,6 +1633,77 @@
return 0;
}
+static int dwc3_msm_pm_suspend(struct device *dev)
+{
+ int ret = 0;
+ struct dwc3_msm *mdwc = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "dwc3-msm PM suspend\n");
+
+ ret = dwc3_msm_suspend(mdwc);
+ if (!ret)
+ atomic_set(&mdwc->pm_suspended, 1);
+
+ return ret;
+}
+
+static int dwc3_msm_pm_resume(struct device *dev)
+{
+ int ret = 0;
+ struct dwc3_msm *mdwc = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "dwc3-msm PM resume\n");
+
+ atomic_set(&mdwc->pm_suspended, 0);
+ if (mdwc->resume_pending) {
+ mdwc->resume_pending = false;
+
+ ret = dwc3_msm_resume(mdwc);
+ /* Update runtime PM status */
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
+ /* Let OTG know about resume event and update pm_count */
+ if (mdwc->otg_xceiv)
+ mdwc->ext_xceiv.notify_ext_events(mdwc->otg_xceiv->otg,
+ DWC3_EVENT_PHY_RESUME);
+ }
+
+ return ret;
+}
+
+static int dwc3_msm_runtime_idle(struct device *dev)
+{
+ dev_dbg(dev, "DWC3-msm runtime idle\n");
+
+ return 0;
+}
+
+static int dwc3_msm_runtime_suspend(struct device *dev)
+{
+ struct dwc3_msm *mdwc = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "DWC3-msm runtime suspend\n");
+
+ return dwc3_msm_suspend(mdwc);
+}
+
+static int dwc3_msm_runtime_resume(struct device *dev)
+{
+ struct dwc3_msm *mdwc = dev_get_drvdata(dev);
+
+ dev_dbg(dev, "DWC3-msm runtime resume\n");
+
+ return dwc3_msm_resume(mdwc);
+}
+
+static const struct dev_pm_ops dwc3_msm_dev_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(dwc3_msm_pm_suspend, dwc3_msm_pm_resume)
+ SET_RUNTIME_PM_OPS(dwc3_msm_runtime_suspend, dwc3_msm_runtime_resume,
+ dwc3_msm_runtime_idle)
+};
+
static const struct of_device_id of_dwc3_matach[] = {
{
.compatible = "qcom,dwc-usb3-msm",
@@ -1464,6 +1717,7 @@
.remove = __devexit_p(dwc3_msm_remove),
.driver = {
.name = "msm-dwc3",
+ .pm = &dwc3_msm_dev_pm_ops,
.of_match_table = of_dwc3_matach,
},
};
diff --git a/drivers/usb/dwc3/dwc3_otg.c b/drivers/usb/dwc3/dwc3_otg.c
index 23b582d..4a37f03 100644
--- a/drivers/usb/dwc3/dwc3_otg.c
+++ b/drivers/usb/dwc3/dwc3_otg.c
@@ -271,6 +271,61 @@
return 0;
}
+/**
+ * dwc3_ext_event_notify - callback to handle events from external transceiver
+ * @otg: Pointer to the otg transceiver structure
+ * @event: Event reported by transceiver
+ *
+ * Returns 0 on success
+ */
+static void dwc3_ext_event_notify(struct usb_otg *otg,
+ enum dwc3_ext_events event)
+{
+ struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
+ struct dwc3_ext_xceiv *ext_xceiv = dotg->ext_xceiv;
+ struct usb_phy *phy = dotg->otg.phy;
+
+ if (event == DWC3_EVENT_PHY_RESUME) {
+ if (!pm_runtime_status_suspended(phy->dev)) {
+ dev_warn(phy->dev, "PHY_RESUME event out of LPM!!!!\n");
+ } else {
+ dev_dbg(phy->dev, "ext PHY_RESUME event received\n");
+ /* ext_xceiver would have taken h/w out of LPM by now */
+ pm_runtime_get(phy->dev);
+ }
+ }
+
+ if (ext_xceiv->id == DWC3_ID_FLOAT)
+ set_bit(ID, &dotg->inputs);
+ else
+ clear_bit(ID, &dotg->inputs);
+
+ if (ext_xceiv->bsv)
+ set_bit(B_SESS_VLD, &dotg->inputs);
+ else
+ clear_bit(B_SESS_VLD, &dotg->inputs);
+
+ schedule_work(&dotg->sm_work);
+}
+
+/**
+ * dwc3_set_ext_xceiv - bind/unbind external transceiver driver
+ * @otg: Pointer to the otg transceiver structure
+ * @ext_xceiv: Pointer to the external transceiver struccture
+ *
+ * Returns 0 on success
+ */
+int dwc3_set_ext_xceiv(struct usb_otg *otg, struct dwc3_ext_xceiv *ext_xceiv)
+{
+ struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
+
+ dotg->ext_xceiv = ext_xceiv;
+ if (ext_xceiv)
+ ext_xceiv->notify_ext_events = dwc3_ext_event_notify;
+
+ return 0;
+}
+
/* IRQs which OTG driver is interested in handling */
#define DWC3_OEVT_MASK (DWC3_OEVTEN_OTGCONIDSTSCHNGEVNT | \
DWC3_OEVTEN_OTGBDEVVBUSCHNGEVNT)
@@ -284,10 +339,21 @@
static irqreturn_t dwc3_otg_interrupt(int irq, void *_dotg)
{
struct dwc3_otg *dotg = (struct dwc3_otg *)_dotg;
+ struct usb_phy *phy = dotg->otg.phy;
u32 osts, oevt_reg;
int ret = IRQ_NONE;
int handled_irqs = 0;
+ /*
+ * If PHY is in retention mode then this interrupt would not be fired.
+ * ext_xcvr (parent) is responsible for bringing h/w out of LPM.
+ * OTG driver just need to increment power count and can safely
+ * assume that h/w is out of low power state now.
+ * TODO: explicitly disable OEVTEN interrupts if ext_xceiv is present
+ */
+ if (pm_runtime_status_suspended(phy->dev))
+ pm_runtime_get(phy->dev);
+
oevt_reg = dwc3_readl(dotg->regs, DWC3_OEVT);
if (!(oevt_reg & DWC3_OEVT_MASK))
@@ -371,6 +437,7 @@
struct dwc3_charger *charger = dotg->charger;
bool work = 0;
+ pm_runtime_resume(phy->dev);
dev_dbg(phy->dev, "%s state\n", otg_state_string(phy->state));
/* Check OTG state */
@@ -388,7 +455,8 @@
work = 1;
} else {
phy->state = OTG_STATE_B_IDLE;
- /* TODO: Enter low power state */
+ dev_dbg(phy->dev, "No device, trying to suspend\n");
+ pm_runtime_put_sync(phy->dev);
}
break;
@@ -411,7 +479,8 @@
/* Has charger been detected? If no detect it */
switch (charger->chg_type) {
case DWC3_DCP_CHARGER:
- /* TODO: initiate LPM */
+ dev_dbg(phy->dev, "lpm, DCP charger\n");
+ pm_runtime_put_sync(phy->dev);
break;
case DWC3_CDP_CHARGER:
dwc3_otg_start_peripheral(&dotg->otg,
@@ -438,9 +507,10 @@
* yet. We will re-try as soon as it
* will be called
*/
- dev_err(phy->dev,
+ dev_err(phy->dev, "enter lpm as\n"
"unable to start B-device\n");
phy->state = OTG_STATE_UNDEFINED;
+ pm_runtime_put_sync(phy->dev);
return;
}
}
@@ -453,7 +523,8 @@
charger->chg_type =
DWC3_INVALID_CHARGER;
}
- /* TODO: Enter low power state */
+ dev_dbg(phy->dev, "No device, trying to suspend\n");
+ pm_runtime_put_sync(phy->dev);
}
break;
@@ -481,9 +552,10 @@
* Probably set_host was not called yet.
* We will re-try as soon as it will be called
*/
- dev_dbg(phy->dev,
+ dev_dbg(phy->dev, "enter lpm as\n"
"unable to start A-device\n");
phy->state = OTG_STATE_UNDEFINED;
+ pm_runtime_put_sync(phy->dev);
return;
}
phy->state = OTG_STATE_A_HOST;
@@ -628,6 +700,8 @@
goto err3;
}
+ pm_runtime_get(dwc->dev);
+
return 0;
err3:
@@ -658,6 +732,7 @@
dotg->charger->start_detection(dotg->charger, false);
cancel_work_sync(&dotg->sm_work);
usb_set_transceiver(NULL);
+ pm_runtime_put(dwc->dev);
free_irq(dotg->irq, dotg);
kfree(dotg->otg.phy);
kfree(dotg);
diff --git a/drivers/usb/dwc3/dwc3_otg.h b/drivers/usb/dwc3/dwc3_otg.h
index 0d8b61b..b60b42a 100644
--- a/drivers/usb/dwc3/dwc3_otg.h
+++ b/drivers/usb/dwc3/dwc3_otg.h
@@ -35,8 +35,9 @@
struct usb_otg otg;
int irq;
void __iomem *regs;
- struct work_struct sm_work;
- struct dwc3_charger *charger;
+ struct work_struct sm_work;
+ struct dwc3_charger *charger;
+ struct dwc3_ext_xceiv *ext_xceiv;
#define ID 0
#define B_SESS_VLD 1
unsigned long inputs;
@@ -73,4 +74,29 @@
/* for external charger driver */
extern int dwc3_set_charger(struct usb_otg *otg, struct dwc3_charger *charger);
+enum dwc3_ext_events {
+ DWC3_EVENT_NONE = 0, /* no change event */
+ DWC3_EVENT_PHY_RESUME, /* PHY has come out of LPM */
+ DWC3_EVENT_XCEIV_STATE, /* XCEIV state (id/bsv) has changed */
+};
+
+enum dwc3_id_state {
+ DWC3_ID_GROUND = 0,
+ DWC3_ID_FLOAT,
+};
+
+/* external transceiver that can perform connect/disconnect monitoring in LPM */
+struct dwc3_ext_xceiv {
+ enum dwc3_id_state id;
+ bool bsv;
+
+ /* to notify OTG about LPM exit event, provided by OTG */
+ void (*notify_ext_events)(struct usb_otg *otg,
+ enum dwc3_ext_events ext_event);
+};
+
+/* for external transceiver driver */
+extern int dwc3_set_ext_xceiv(struct usb_otg *otg,
+ struct dwc3_ext_xceiv *ext_xceiv);
+
#endif /* __LINUX_USB_DWC3_OTG_H */
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 060144f..a3f6e58 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2425,6 +2425,11 @@
dev_err(dwc->dev, "failed to set peripheral to otg\n");
goto err7;
}
+ } else {
+ pm_runtime_no_callbacks(&dwc->gadget.dev);
+ pm_runtime_set_active(&dwc->gadget.dev);
+ pm_runtime_enable(&dwc->gadget.dev);
+ pm_runtime_get(&dwc->gadget.dev);
}
return 0;
@@ -2462,6 +2467,11 @@
{
int irq;
+ if (dwc->dotg) {
+ pm_runtime_put(&dwc->gadget.dev);
+ pm_runtime_disable(&dwc->gadget.dev);
+ }
+
usb_del_gadget_udc(&dwc->gadget);
irq = platform_get_irq(to_platform_device(dwc->dev), 0);
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 8467dc0..d895f27 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -12,6 +12,7 @@
*/
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb/otg.h>
@@ -173,6 +174,11 @@
usb_put_transceiver(phy);
goto put_usb3_hcd;
}
+ } else {
+ pm_runtime_no_callbacks(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+ pm_runtime_get(&pdev->dev);
}
return 0;
@@ -211,6 +217,9 @@
if (phy && phy->otg) {
otg_set_host(phy->otg, NULL);
usb_put_transceiver(phy);
+ } else {
+ pm_runtime_put(&dev->dev);
+ pm_runtime_disable(&dev->dev);
}
return 0;