env: Add a baudrate env handler

Remove the hard-coded baudrate handler and use a callback instead

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

1 files changed, 70 insertions, 0 deletions

diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index f5f43a6ddc..1f8955a0fd 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -22,6 +22,7 @@
  */
 
 #include <common.h>
+#include <environment.h>
 #include <serial.h>
 #include <stdio_dev.h>
 #include <post.h>
@@ -32,6 +33,11 @@ DECLARE_GLOBAL_DATA_PTR;
 
 static struct serial_device *serial_devices;
 static struct serial_device *serial_current;
+/*
+ * Table with supported baudrates (defined in config_xyz.h)
+ */
+static const unsigned long baudrate_table[] = CONFIG_SYS_BAUDRATE_TABLE;
+#define	N_BAUDRATES (sizeof(baudrate_table) / sizeof(baudrate_table[0]))
 
 /**
  * serial_null() - Void registration routine of a serial driver
@@ -46,6 +52,70 @@ static void serial_null(void)
 }
 
 /**
+ * on_baudrate() - Update the actual baudrate when the env var changes
+ *
+ * This will check for a valid baudrate and only apply it if valid.
+ */
+static int on_baudrate(const char *name, const char *value, enum env_op op,
+	int flags)
+{
+	int i;
+	int baudrate;
+
+	switch (op) {
+	case env_op_create:
+	case env_op_overwrite:
+		/*
+		 * Switch to new baudrate if new baudrate is supported
+		 */
+		baudrate = simple_strtoul(value, NULL, 10);
+
+		/* Not actually changing */
+		if (gd->baudrate == baudrate)
+			return 0;
+
+		for (i = 0; i < N_BAUDRATES; ++i) {
+			if (baudrate == baudrate_table[i])
+				break;
+		}
+		if (i == N_BAUDRATES) {
+			if ((flags & H_FORCE) == 0)
+				printf("## Baudrate %d bps not supported\n",
+					baudrate);
+			return 1;
+		}
+		if ((flags & H_INTERACTIVE) != 0) {
+			printf("## Switch baudrate to %d"
+				" bps and press ENTER ...\n", baudrate);
+			udelay(50000);
+		}
+
+		gd->baudrate = baudrate;
+#if defined(CONFIG_PPC) || defined(CONFIG_MCF52x2)
+		gd->bd->bi_baudrate = baudrate;
+#endif
+
+		serial_setbrg();
+
+		udelay(50000);
+
+		if ((flags & H_INTERACTIVE) != 0)
+			while (1) {
+				if (getc() == '\r')
+					break;
+			}
+
+		return 0;
+	case env_op_delete:
+		printf("## Baudrate may not be deleted\n");
+		return 1;
+	default:
+		return 0;
+	}
+}
+U_BOOT_ENV_CALLBACK(baudrate, on_baudrate);
+
+/**
  * serial_initfunc() - Forward declare of driver registration routine
  * @name:	Name of the real driver registration routine.
  *