[PATCH v6 5/9] coresight: tmc: Introduce sysfs_read_ops to wrap sysfs read operations

[Jie Gan <jie.gan@oss.qualcomm.com>]

Introduce sysfs_read_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 | 50 +++++++++++-------------
 drivers/hwtracing/coresight/coresight-tmc.h      | 18 +++++++++
 2 files changed, 41 insertions(+), 27 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 4d249af93097..ccb177d953b9 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");
@@ -291,13 +277,8 @@ 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);
-	}
+	if (drvdata->sysfs_ops)
+		return drvdata->sysfs_ops->get_trace_data(drvdata, pos, len, bufpp);
 
 	return -EINVAL;
 }
@@ -769,6 +750,18 @@ static void register_crash_dev_interface(struct tmc_drvdata *drvdata,
 			"Valid crash tracedata found\n");
 }
 
+static const struct sysfs_read_ops tmc_etb_sysfs_read_ops = {
+	.read_prepare	= tmc_read_prepare_etb,
+	.read_unprepare	= tmc_read_unprepare_etb,
+	.get_trace_data	= tmc_etb_get_sysfs_trace,
+};
+
+static const struct sysfs_read_ops tmc_etr_sysfs_read_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;
@@ -818,6 +811,7 @@ 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 = &tmc_etb_sysfs_read_ops;
 		break;
 	case TMC_CONFIG_TYPE_ETR:
 		desc.groups = coresight_etr_groups;
@@ -831,6 +825,7 @@ 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 = &tmc_etr_sysfs_read_ops;
 		break;
 	case TMC_CONFIG_TYPE_ETF:
 		desc.groups = coresight_etf_groups;
@@ -839,6 +834,7 @@ 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 = &tmc_etb_sysfs_read_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 ca0cba860d5f..0d0a547cb042 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -221,6 +221,9 @@ struct etr_buf_node {
 	struct list_head	node;
 };
 
+
+struct sysfs_read_ops;
+
 /**
  * struct tmc_drvdata - specifics associated to an TMC component
  * @pclk:	APB clock if present, otherwise NULL
@@ -257,6 +260,7 @@ struct etr_buf_node {
  *		 Used by ETR/ETF.
  * @etr_buf_list: List that is used to manage allocated etr_buf.
  * @reading_node: Available buffer for byte-cntr reading.
+ * @sysfs_ops:	Read operations for sysfs mode.
  */
 struct tmc_drvdata {
 	struct clk		*pclk;
@@ -288,6 +292,20 @@ struct tmc_drvdata {
 	struct tmc_resrv_buf	crash_mdata;
 	struct list_head        etr_buf_list;
 	struct etr_buf_node     *reading_node;
+	const struct sysfs_read_ops	*sysfs_ops;
+};
+
+/**
+ * struct sysfs_read_ops - read operations for TMC and its helper devices
+ * @read_prepare:	prepare operation.
+ * @read_unprepare:	unprepare operation.
+ * @get_trace_data:	read operation.
+ */
+struct sysfs_read_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