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/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,
},
};