serial: sh-sci: Add more Serial Port Register documentation

Improve documentation for the (H)SCIF Serial Port Register:
  - Make it clear the RTS and CTS lines are active-low,
  - Document the bits related to the serial port's clock pin.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sh-sci.h b/drivers/tty/serial/sh-sci.h
index 7a4fa18..85a2b81 100644 (file)
--- a/drivers/tty/serial/sh-sci.h
+++ b/drivers/tty/serial/sh-sci.h
@@ -108,10 +108,12 @@ enum {
 #define SCLSR_ORER     BIT(0)  /* Overrun Error */
 
 /* SCSPTR (Serial Port Register), optional */
-#define SCSPTR_RTSIO   BIT(7)  /* Serial Port RTS Pin Input/Output */
-#define SCSPTR_RTSDT   BIT(6)  /* Serial Port RTS Pin Data */
-#define SCSPTR_CTSIO   BIT(5)  /* Serial Port CTS Pin Input/Output */
-#define SCSPTR_CTSDT   BIT(4)  /* Serial Port CTS Pin Data */
+#define SCSPTR_RTSIO   BIT(7)  /* Serial Port RTS# Pin Input/Output */
+#define SCSPTR_RTSDT   BIT(6)  /* Serial Port RTS# Pin Data */
+#define SCSPTR_CTSIO   BIT(5)  /* Serial Port CTS# Pin Input/Output */
+#define SCSPTR_CTSDT   BIT(4)  /* Serial Port CTS# Pin Data */
+#define SCSPTR_SCKIO   BIT(3)  /* Serial Port Clock Pin Input/Output */
+#define SCSPTR_SCKDT   BIT(2)  /* Serial Port Clock Pin Data */
 #define SCSPTR_SPB2IO  BIT(1)  /* Serial Port Break Input/Output */
 #define SCSPTR_SPB2DT  BIT(0)  /* Serial Port Break Data */