Merge "dwc3: Check USB LPM status before accessing any register"

2 files changed, 41 insertions, 4 deletions

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 8f36f3df55eb..9f73ec68a23b 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -852,6 +852,7 @@ struct dwc3_scratchpad_array {
  * @vbus_draw: current to be drawn from USB
  * @imod_interval: set the interrupt moderation interval in 250ns
  *			increments or 0 to disable.
+ * @create_reg_debugfs: create debugfs entry to allow dwc3 register dump
  */
 struct dwc3 {
 	struct usb_ctrlrequest	*ctrl_req;
@@ -1048,6 +1049,7 @@ struct dwc3 {
 	unsigned long		l1_remote_wakeup_cnt;
 
 	wait_queue_head_t	wait_linkstate;
+	bool			create_reg_debugfs;
 };
 
 /* -------------------------------------------------------------------------- */
diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c
index 4a18847983f7..2c00b3596055 100644
--- a/drivers/usb/dwc3/debugfs.c
+++ b/drivers/usb/dwc3/debugfs.c
@@ -368,6 +368,11 @@ static int dwc3_mode_show(struct seq_file *s, void *unused)
 	unsigned long		flags;
 	u32			reg;
 
+	if (atomic_read(&dwc->in_lpm)) {
+		seq_puts(s, "USB device is powered off\n");
+		return 0;
+	}
+
 	spin_lock_irqsave(&dwc->lock, flags);
 	reg = dwc3_readl(dwc->regs, DWC3_GCTL);
 	spin_unlock_irqrestore(&dwc->lock, flags);
@@ -403,6 +408,11 @@ static ssize_t dwc3_mode_write(struct file *file,
 	u32			mode = 0;
 	char buf[32] = {};
 
+	if (atomic_read(&dwc->in_lpm)) {
+		dev_err(dwc->dev, "USB device is powered off\n");
+		return count;
+	}
+
 	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
 		return -EFAULT;
 
@@ -437,6 +447,12 @@ static int dwc3_testmode_show(struct seq_file *s, void *unused)
 	unsigned long		flags;
 	u32			reg;
 
+
+	if (atomic_read(&dwc->in_lpm)) {
+		seq_puts(s, "USB device is powered off\n");
+		return 0;
+	}
+
 	spin_lock_irqsave(&dwc->lock, flags);
 	reg = dwc3_readl(dwc->regs, DWC3_DCTL);
 	reg &= DWC3_DCTL_TSTCTRL_MASK;
@@ -483,6 +499,11 @@ static ssize_t dwc3_testmode_write(struct file *file,
 	u32			testmode = 0;
 	char			buf[32] = {};
 
+	if (atomic_read(&dwc->in_lpm)) {
+		seq_puts(s, "USB device is powered off\n");
+		return count;
+	}
+
 	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
 		return -EFAULT;
 
@@ -521,6 +542,11 @@ static int dwc3_link_state_show(struct seq_file *s, void *unused)
 	enum dwc3_link_state	state;
 	u32			reg;
 
+	if (atomic_read(&dwc->in_lpm)) {
+		seq_puts(s, "USB device is powered off\n");
+		return 0;
+	}
+
 	spin_lock_irqsave(&dwc->lock, flags);
 	reg = dwc3_readl(dwc->regs, DWC3_DSTS);
 	state = DWC3_DSTS_USBLNKST(reg);
@@ -590,6 +616,11 @@ static ssize_t dwc3_link_state_write(struct file *file,
 	enum dwc3_link_state	state = 0;
 	char			buf[32] = {};
 
+	if (atomic_read(&dwc->in_lpm)) {
+		seq_puts(s, "USB device is powered off\n");
+		return count;
+	}
+
 	if (copy_from_user(&buf, ubuf, min_t(size_t, sizeof(buf) - 1, count)))
 		return -EFAULT;
 
@@ -1241,10 +1272,14 @@ int dwc3_debugfs_init(struct dwc3 *dwc)
 	dwc->regset->nregs = ARRAY_SIZE(dwc3_regs);
 	dwc->regset->base = dwc->regs;
 
-	file = debugfs_create_regset32("regdump", S_IRUGO, root, dwc->regset);
-	if (!file) {
-		ret = -ENOMEM;
-		goto err1;
+	if (dwc->create_reg_debugfs) {
+		file = debugfs_create_regset32("regdump", 0444,
+						root, dwc->regset);
+		if (!file) {
+			dev_dbg(dwc->dev, "Can't create debugfs regdump\n");
+			ret = -ENOMEM;
+			goto err1;
+		}
 	}
 
 	if (IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)) {