[PATCH v6 01/10] coresight-tpdm: Optimize the store function of tpdm simple dataset

[Tao Zhang]

Replace spin lock/unlock to avoid forgetting to unlock when the
function exits. And refine methods for handling various conditions.

Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
---
 drivers/hwtracing/coresight/coresight-tpdm.c | 39 ++++++++++----------
 1 file changed, 19 insertions(+), 20 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index bd13a548375c..0427c0fc0bf3 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -77,51 +77,50 @@ static ssize_t tpdm_simple_dataset_store(struct device *dev,
 					 size_t size)
 {
 	unsigned long val;
-	ssize_t ret = size;
+	ssize_t ret = -EINVAL;
 
 	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct tpdm_dataset_attribute *tpdm_attr =
 		container_of(attr, struct tpdm_dataset_attribute, attr);
 
 	if (kstrtoul(buf, 0, &val))
-		return -EINVAL;
+		return ret;
 
-	spin_lock(&drvdata->spinlock);
+	guard(spinlock)(&drvdata->spinlock);
 	switch (tpdm_attr->mem) {
 	case DSB_TRIG_PATT:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->trig_patt[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_TRIG_PATT_MASK:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->trig_patt_mask[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_PATT:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->patt_val[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_PATT_MASK:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->patt_mask[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_MSR:
-		if (tpdm_attr->idx < drvdata->dsb_msr_num)
+		if (tpdm_attr->idx < drvdata->dsb_msr_num) {
 			drvdata->dsb->msr[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	default:
-		ret = -EINVAL;
+		break;
 	}
-	spin_unlock(&drvdata->spinlock);
 
 	return ret;
 }
-- 
2.17.1