[PATCH v2] staging: greybus: uart: add descriptive lock comments

[Shubham Chakraborty <chakrabortyshubham66@gmail.com>]

Replace vague lock comments with specific descriptions of
what data each lock protects:
- read_lock: protects iocount and oldcount
- write_lock: protects write_fifo and credits
- mutex: protects disconnected state

Signed-off-by: Shubham Chakraborty <chakrabortyshubham66@gmail.com>
---
 drivers/staging/greybus/uart.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/greybus/uart.c b/drivers/staging/greybus/uart.c
index fe554eba555a..1e51818e34a8 100644
--- a/drivers/staging/greybus/uart.c
+++ b/drivers/staging/greybus/uart.c
@@ -50,12 +50,12 @@ struct gb_tty {
 	unsigned int minor;
 	unsigned char clocal;
 	bool disconnected;
-	spinlock_t read_lock;		/* protects read operations */
-	spinlock_t write_lock;		/* protects write operations */
+	spinlock_t read_lock;		/* protects iocount and oldcount */
+	spinlock_t write_lock;		/* protects write_fifo and credits */
 	struct async_icount iocount;
 	struct async_icount oldcount;
 	wait_queue_head_t wioctl;
-	struct mutex mutex;		/* serializes port operations */
+	struct mutex mutex;		/* protects disconnected state */
 	u8 ctrlin;	/* input control lines */
 	u8 ctrlout;	/* output control lines */
 	struct gb_uart_set_line_coding_request line_coding;
-- 
2.53.0