[PATCH v2 5/5] usb: dwc3: debugfs: Print/set link state for peripheral mode

[Thinh Nguyen]

Current implementation only prints/sets the link state for peripheral
mode only. Check and prevent printing bogus link state if the current
mode of operation is not peripheral.

Signed-off-by: Thinh Nguyen <thi...@synopsys.com>
---
Change in v2:
 - New patch, no previous change

 drivers/usb/dwc3/debugfs.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c
index e613a61ae58a..1c792710348f 100644
--- a/drivers/usb/dwc3/debugfs.c
+++ b/drivers/usb/dwc3/debugfs.c
@@ -542,6 +542,13 @@ static int dwc3_link_state_show(struct seq_file *s, void 
*unused)
        u8                      speed;
 
        spin_lock_irqsave(&dwc->lock, flags);
+       reg = dwc3_readl(dwc->regs, DWC3_GSTS);
+       if (DWC3_GSTS_CURMOD(reg) != DWC3_GSTS_CURMOD_DEVICE) {
+               seq_puts(s, "Not available\n");
+               spin_unlock_irqrestore(&dwc->lock, flags);
+               return 0;
+       }
+
        reg = dwc3_readl(dwc->regs, DWC3_DSTS);
        state = DWC3_DSTS_USBLNKST(reg);
        speed = reg & DWC3_DSTS_CONNECTSPD;
@@ -589,6 +596,12 @@ static ssize_t dwc3_link_state_write(struct file *file,
                return -EINVAL;
 
        spin_lock_irqsave(&dwc->lock, flags);
+       reg = dwc3_readl(dwc->regs, DWC3_GSTS);
+       if (DWC3_GSTS_CURMOD(reg) != DWC3_GSTS_CURMOD_DEVICE) {
+               spin_unlock_irqrestore(&dwc->lock, flags);
+               return -EINVAL;
+       }
+
        reg = dwc3_readl(dwc->regs, DWC3_DSTS);
        speed = reg & DWC3_DSTS_CONNECTSPD;
 
-- 
2.11.0