[PATCH -next] hwmon: (pmbus) fix build error unused-function

[Ren Zhijie <renzhijie2@huawei.com>]

If CONFIG_PMBUS is y and CONFIG_DEBUG_FS is not set.

make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu-, will be failed, like this:
drivers/hwmon/pmbus/pmbus_core.c:593:13: error: ‘pmbus_check_block_register’ defined but not used [-Werror=unused-function]
 static bool pmbus_check_block_register(struct i2c_client *client, int page,
             ^~~~~~~~~~~~~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
make[3]: *** [drivers/hwmon/pmbus/pmbus_core.o] Error 1
make[2]: *** [drivers/hwmon/pmbus] Error 2
make[2]: *** Waiting for unfinished jobs....
make[1]: *** [drivers/hwmon] Error 2
make[1]: *** Waiting for unfinished jobs....
make: *** [drivers] Error 2

To fix building warning, wrap all related code with CONFIG_DEBUG_F.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: c3ffc3a1ff83("hwmon: (pmbus) add a function to check the presence of a block register")
Signed-off-by: Ren Zhijie <renzhijie2@huawei.com>
---
 drivers/hwmon/pmbus/pmbus_core.c | 56 ++++++++++++++++----------------
 1 file changed, 28 insertions(+), 28 deletions(-)

diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 809e666cb52b..2c68ab1fe697 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -441,18 +441,6 @@ int pmbus_update_byte_data(struct i2c_client *client, int page, u8 reg,
 }
 EXPORT_SYMBOL_NS_GPL(pmbus_update_byte_data, PMBUS);
 
-static int pmbus_read_block_data(struct i2c_client *client, int page, u8 reg,
-				 char *data_buf)
-{
-	int rv;
-
-	rv = pmbus_set_page(client, page, 0xff);
-	if (rv < 0)
-		return rv;
-
-	return i2c_smbus_read_block_data(client, reg, data_buf);
-}
-
 static struct pmbus_sensor *pmbus_find_sensor(struct pmbus_data *data, int page,
 					      int reg)
 {
@@ -590,22 +578,6 @@ bool pmbus_check_word_register(struct i2c_client *client, int page, int reg)
 }
 EXPORT_SYMBOL_NS_GPL(pmbus_check_word_register, PMBUS);
 
-static bool pmbus_check_block_register(struct i2c_client *client, int page,
-				       int reg)
-{
-	int rv;
-	struct pmbus_data *data = i2c_get_clientdata(client);
-	char data_buf[I2C_SMBUS_BLOCK_MAX + 2];
-
-	rv = pmbus_read_block_data(client, page, reg, data_buf);
-	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
-		rv = pmbus_check_status_cml(client);
-	if (rv < 0 && (data->flags & PMBUS_READ_STATUS_AFTER_FAILED_CHECK))
-		data->read_status(client, -1);
-	pmbus_clear_fault_page(client, -1);
-	return rv >= 0;
-}
-
 const struct pmbus_driver_info *pmbus_get_driver_info(struct i2c_client *client)
 {
 	struct pmbus_data *data = i2c_get_clientdata(client);
@@ -2961,6 +2933,34 @@ static int pmbus_regulator_register(struct pmbus_data *data)
 static struct dentry *pmbus_debugfs_dir;	/* pmbus debugfs directory */
 
 #if IS_ENABLED(CONFIG_DEBUG_FS)
+static int pmbus_read_block_data(struct i2c_client *client, int page, u8 reg,
+				 char *data_buf)
+{
+	int rv;
+
+	rv = pmbus_set_page(client, page, 0xff);
+	if (rv < 0)
+		return rv;
+
+	return i2c_smbus_read_block_data(client, reg, data_buf);
+}
+
+static bool pmbus_check_block_register(struct i2c_client *client, int page,
+				       int reg)
+{
+	int rv;
+	struct pmbus_data *data = i2c_get_clientdata(client);
+	char data_buf[I2C_SMBUS_BLOCK_MAX + 2];
+
+	rv = pmbus_read_block_data(client, page, reg, data_buf);
+	if (rv >= 0 && !(data->flags & PMBUS_SKIP_STATUS_CHECK))
+		rv = pmbus_check_status_cml(client);
+	if (rv < 0 && (data->flags & PMBUS_READ_STATUS_AFTER_FAILED_CHECK))
+		data->read_status(client, -1);
+	pmbus_clear_fault_page(client, -1);
+	return rv >= 0;
+}
+
 static int pmbus_debugfs_get(void *data, u64 *val)
 {
 	int rc;
-- 
2.17.1