Round the serial port clock divisor value returned by calc_divisor()
Round the serial port clock divisor value returned by
calc_divisor().
Signed-off-by: Hugo Villeneuve <hugo.villeneuve@lyrtech.com>
Signed-off-by: John Roberts <john.roberts@pwav.com>
diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index 76425d8..182ca2d 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -144,8 +144,13 @@
#else
#define MODE_X_DIV 16
#endif
- return (CFG_NS16550_CLK / MODE_X_DIV / gd->baudrate);
+ /* Compute divisor value. Normally, we should simply return:
+ * CFG_NS16550_CLK) / MODE_X_DIV / gd->baudrate
+ * but we need to round that value by adding 0.5 or 8/16.
+ * Rounding is especially important at high baud rates.
+ */
+ return (((16 * CFG_NS16550_CLK) / MODE_X_DIV / gd->baudrate) + 8) / 16;
}
#if !defined(CONFIG_SERIAL_MULTI)