Re: [PATCH v2 1/3] coresight: catu: Introduce refcount and spinlock for enabling/disabling

Hi Yabin,

On Tue, Apr 01, 2025 at 06:21:59PM -0700, Yabin Cui wrote:

[...]

...

@@ -486,12 +491,17 @@ static int catu_disable_hw(struct catu_drvdata *drvdata)

static int catu_disable(struct coresight_device *csdev, void *__unused) {

•   int rc;
  

•   int rc = 0;
    struct catu_drvdata *catu_drvdata = csdev_to_catu_drvdata(csdev);
  

•   guard(raw_spinlock_irqsave)(&catu_drvdata->spinlock);
  
  

•   CS_UNLOCK(catu_drvdata->base);
  

•   rc = catu_disable_hw(catu_drvdata);
  

•   CS_LOCK(catu_drvdata->base);
  

•   if (--csdev->refcnt == 0) {
  

•           CS_UNLOCK(catu_drvdata->base);
  

•           rc = catu_disable_hw(catu_drvdata);
  

•           CS_LOCK(catu_drvdata->base);
  

•   } else {
  

•           rc = -EBUSY;
  

This is not an error if the decremented reference counter is not zero. It should return 0. Otherwise, the change looks good to me.

Thanks, Leo