hwmon: (pmbus/core) Add PMBUS_REVISION in debugfs

Add debugfs file for the PMBUS_REVISION command. This command provides
information about PMBus protocol revision number.

Signed-off-by: Ninad Palsule <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Guenter Roeck <[email protected]>

Author: ninadpalsule

drivers/hwmon/pmbus/pmbus_core.c

@@ -3534,11 +3534,11 @@ static int pmbus_init_debugfs(struct i2c_client *client,
 
 	/*
 	 * Allocate the max possible entries we need.
-	 * 6 entries device-specific
+	 * 7 entries device-specific
 	 * 10 entries page-specific
 	 */
 	entries = devm_kcalloc(data->dev,
-			       6 + data->info->pages * 10, sizeof(*entries),
+			       7 + data->info->pages * 10, sizeof(*entries),
 			       GFP_KERNEL);
 	if (!entries)
 		return -ENOMEM;
@@ -3551,6 +3551,15 @@ static int pmbus_init_debugfs(struct i2c_client *client,
 	 * assume that values of the following registers are the same for all
 	 * pages and report values only for page 0.
 	 */
+	if (pmbus_check_byte_register(client, 0, PMBUS_REVISION)) {
+		entries[idx].client = client;
+		entries[idx].page = 0;
+		entries[idx].reg = PMBUS_REVISION;
+		debugfs_create_file("revision", 0444, data->debugfs,
+				    &entries[idx++],
+				    &pmbus_debugfs_ops);
+	}
+
 	if (pmbus_check_block_register(client, 0, PMBUS_MFR_ID)) {
 		entries[idx].client = client;
 		entries[idx].page = 0;