Introduce tmc_sysfs_ops as a wrapper, wrap sysfs read operations, for reading
trace data from the TMC buffer.

Reviewed-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Jie Gan <jie.gan@oss.qualcomm.com>
---
 drivers/hwtracing/coresight/coresight-tmc-core.c | 51 ++++++++++--------------
 drivers/hwtracing/coresight/coresight-tmc.h      | 15 +++++++
 2 files changed, 37 insertions(+), 29 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 1ea255ffa67c..32ca2ec994de 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -232,17 +232,10 @@ static int tmc_read_prepare(struct tmc_drvdata *drvdata)
 {
 	int ret = 0;
 
-	switch (drvdata->config_type) {
-	case TMC_CONFIG_TYPE_ETB:
-	case TMC_CONFIG_TYPE_ETF:
-		ret = tmc_read_prepare_etb(drvdata);
-		break;
-	case TMC_CONFIG_TYPE_ETR:
-		ret = tmc_read_prepare_etr(drvdata);
-		break;
-	default:
+	if (drvdata->sysfs_ops)
+		ret = drvdata->sysfs_ops->read_prepare(drvdata);
+	else
 		ret = -EINVAL;
-	}
 
 	if (!ret)
 		dev_dbg(&drvdata->csdev->dev, "TMC read start\n");
@@ -254,17 +247,10 @@ static int tmc_read_unprepare(struct tmc_drvdata *drvdata)
 {
 	int ret = 0;
 
-	switch (drvdata->config_type) {
-	case TMC_CONFIG_TYPE_ETB:
-	case TMC_CONFIG_TYPE_ETF:
-		ret = tmc_read_unprepare_etb(drvdata);
-		break;
-	case TMC_CONFIG_TYPE_ETR:
-		ret = tmc_read_unprepare_etr(drvdata);
-		break;
-	default:
+	if (drvdata->sysfs_ops)
+		ret = drvdata->sysfs_ops->read_unprepare(drvdata);
+	else
 		ret = -EINVAL;
-	}
 
 	if (!ret)
 		dev_dbg(&drvdata->csdev->dev, "TMC read end\n");
@@ -291,15 +277,7 @@ static int tmc_open(struct inode *inode, struct file *file)
 static ssize_t tmc_get_sysfs_trace(struct tmc_drvdata *drvdata, loff_t pos, size_t len,
 				   char **bufpp)
 {
-	switch (drvdata->config_type) {
-	case TMC_CONFIG_TYPE_ETB:
-	case TMC_CONFIG_TYPE_ETF:
-		return tmc_etb_get_sysfs_trace(drvdata, pos, len, bufpp);
-	case TMC_CONFIG_TYPE_ETR:
-		return tmc_etr_get_sysfs_trace(drvdata, pos, len, bufpp);
-	}
-
-	return -EINVAL;
+	return drvdata->sysfs_ops->get_trace_data(drvdata, pos, len, bufpp);
 }
 
 static ssize_t tmc_read(struct file *file, char __user *data, size_t len,
@@ -769,6 +747,18 @@ static void register_crash_dev_interface(struct tmc_drvdata *drvdata,
 			"Valid crash tracedata found\n");
 }
 
+static const struct tmc_sysfs_ops etb_sysfs_ops = {
+	.read_prepare	= tmc_read_prepare_etb,
+	.read_unprepare	= tmc_read_unprepare_etb,
+	.get_trace_data	= tmc_etb_get_sysfs_trace,
+};
+
+static const struct tmc_sysfs_ops etr_sysfs_ops = {
+	.read_prepare	= tmc_read_prepare_etr,
+	.read_unprepare	= tmc_read_unprepare_etr,
+	.get_trace_data	= tmc_etr_get_sysfs_trace,
+};
+
 static int __tmc_probe(struct device *dev, struct resource *res)
 {
 	int ret = 0;
@@ -828,6 +818,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
 		desc.subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
 		desc.ops = &tmc_etb_cs_ops;
 		dev_list = &etb_devs;
+		drvdata->sysfs_ops = &etb_sysfs_ops;
 		break;
 	case TMC_CONFIG_TYPE_ETR:
 		desc.groups = coresight_etr_groups;
@@ -841,6 +832,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
 		mutex_init(&drvdata->idr_mutex);
 		dev_list = &etr_devs;
 		INIT_LIST_HEAD(&drvdata->etr_buf_list);
+		drvdata->sysfs_ops = &etr_sysfs_ops;
 		break;
 	case TMC_CONFIG_TYPE_ETF:
 		desc.groups = coresight_etf_groups;
@@ -849,6 +841,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
 		desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_FIFO;
 		desc.ops = &tmc_etf_cs_ops;
 		dev_list = &etf_devs;
+		drvdata->sysfs_ops = &etb_sysfs_ops;
 		break;
 	default:
 		pr_err("%s: Unsupported TMC config\n", desc.name);
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 9b3c4e6f0a5e..c780f6d5dede 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -258,6 +258,7 @@ struct etr_buf_node {
  *		 Used by ETR/ETF.
  * @etr_buf_list: List that is used to manage allocated etr_buf.
  * @reading_node: Available buffer_node for byte-cntr reading.
+ * @sysfs_ops:	Read operations for sysfs mode.
  */
 struct tmc_drvdata {
 	struct clk		*atclk;
@@ -290,6 +291,20 @@ struct tmc_drvdata {
 	struct tmc_resrv_buf	crash_mdata;
 	struct list_head        etr_buf_list;
 	struct etr_buf_node     *reading_node;
+	const struct tmc_sysfs_ops	*sysfs_ops;
+};
+
+/**
+ * struct tmc_sysfs_ops - read operations for TMC and its helper devices
+ * @read_prepare:	prepare operation.
+ * @read_unprepare:	unprepare operation.
+ * @get_trace_data:	read operation.
+ */
+struct tmc_sysfs_ops {
+	int (*read_prepare)(struct tmc_drvdata *drvdata);
+	int (*read_unprepare)(struct tmc_drvdata *drvdata);
+	ssize_t (*get_trace_data)(struct tmc_drvdata *drvdata, loff_t pos,
+				  size_t len, char **bufpp);
 };
 
 struct etr_buf_operations {

-- 
2.34.1