serial: 8250: Document uart_8250_port's ->dl_read/write()

Add documentation for the struct uart_8250_port divisor latch function
pointers. Documentation is in kernel doc format but don't enable kernel
doc yet as many other fields remain undocumented.

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20230511121029.13128-3-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/serial_8250.h b/include/linux/serial_8250.h
index 7b5d558e4e0c34468d9683ed2f9b8be5a9202e2b..d64e7bbe1f2f1c0426cee8164cf5adc518afedeb 100644 (file)
--- a/include/linux/serial_8250.h
+++ b/include/linux/serial_8250.h
@@ -90,8 +90,17 @@ struct uart_8250_em485 {
  * their own 8250 ports without registering their own
  * platform device.  Using these will make your driver
  * dependent on the 8250 driver.
+ *
+ * @dl_read: ``u32 ()(struct uart_8250_port *port)``
+ *
+ *     UART divisor latch read.
+ *
+ * @dl_write: ``void ()(struct uart_8250_port *port, u32 value)``
+ *
+ *     Write @value into UART divisor latch.
+ *
+ *     Locking: Caller holds port's lock.
  */
-
 struct uart_8250_port {
        struct uart_port        port;
        struct timer_list       timer;          /* "no irq" timer */