Title: [9187] trunk/drivers/serial/bfin_sport_uart.c: bfin_sport_uart: speed up sport RX sample rate to be 3% faster
Revision
9187
Author
sonicz
Date
2010-09-30 04:26:50 -0400 (Thu, 30 Sep 2010)

Log Message

bfin_sport_uart: speed up sport RX sample rate to be 3% faster

The actual uart baud rate of devices vary between +/-2% of what is
asked.
The sport rx sample rate should be faster than the double of the worst
case otherwise, wrong data are received. So, set sport RX clock to be
3% faster.

Modified Paths

Diff

Modified: trunk/drivers/serial/bfin_sport_uart.c (9186 => 9187)


--- trunk/drivers/serial/bfin_sport_uart.c	2010-09-30 08:24:49 UTC (rev 9186)
+++ trunk/drivers/serial/bfin_sport_uart.c	2010-09-30 08:26:50 UTC (rev 9187)
@@ -131,7 +131,12 @@
 	pr_debug("%s RCR1:%x, RCR2:%x\n", __func__, SPORT_GET_RCR1(up), SPORT_GET_RCR2(up));
 
 	tclkdiv = sclk / (2 * baud_rate) - 1;
-	rclkdiv = sclk / (2 * baud_rate * 2) - 1;
+	/* The actual uart baud rate of devices vary between +/-2%. The sport
+	 * RX sample rate should be faster than the double of the worst case,
+	 * otherwise, wrong data are received. So, set sport RX clock to be
+	 * 3% faster.
+	 */
+	rclkdiv = sclk / (2 * baud_rate * 2 * 97 / 100) - 1;
 	SPORT_PUT_TCLKDIV(up, tclkdiv);
 	SPORT_PUT_RCLKDIV(up, rclkdiv);
 	SSYNC();
_______________________________________________
Linux-kernel-commits mailing list
[email protected]
https://blackfin.uclinux.org/mailman/listinfo/linux-kernel-commits

Reply via email to