console_output: Add commands for saving / restoring print mask.

Saving + restoring the channel print mask previously involved running
the 'chan' command with no parameters, then parsing the output. This
parsing is unreliable if other tasks are also writing to the console.
Add commands to save / backup the current channel mask, and later
restoring it. Typical method to limit channel mask will now be:

chan save
chan <mask>
...
chan restore

BUG=chromium:269758.
TEST=Run 'chan save' / 'chan 0' / 'chan restore' on EC console, verify
print mask is restored.
BRANCH=Peppy/Falco.

Change-Id: I725c7fb5e3ac7e55ed5f435446f8fc5c54af165f
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/65208
Reviewed-by: Randall Spangler <rspangler@chromium.org>

1 files changed, 24 insertions, 13 deletions

diff --git a/common/console_output.c b/common/console_output.c
index b7985883cc..385c48d0af 100644
--- a/common/console_output.c
+++ b/common/console_output.c
@@ -14,6 +14,7 @@
 #define CC_DEFAULT CC_ALL
 #endif
 static uint32_t channel_mask = CC_DEFAULT;
+static uint32_t channel_mask_saved = CC_DEFAULT;
 
 /* List of channel names; must match enum console_channel. */
 /* TODO: move this to board.c */
@@ -82,18 +83,28 @@ static int command_ch(int argc, char **argv)
 	int i;
 	char *e;
 
-	/* If one arg, set the mask */
+	/* If one arg, save / restore, or set the mask */
 	if (argc == 2) {
-		int m = strtoi(argv[1], &e, 0);
-		if (*e)
-			return EC_ERROR_PARAM1;
-
-		/* No disabling the command output channel */
-		channel_mask = m | CC_MASK(CC_COMMAND);
-
-		/* TODO: save channel list to EEPROM */
-
-		return EC_SUCCESS;
+		if (strcasecmp(argv[1], "save") == 0) {
+			channel_mask_saved = channel_mask;
+			return EC_SUCCESS;
+		} else if (strcasecmp(argv[1], "restore") == 0) {
+			channel_mask = channel_mask_saved;
+			return EC_SUCCESS;
+
+		} else {
+			/* Set the mask */
+			int m = strtoi(argv[1], &e, 0);
+			if (*e)
+				return EC_ERROR_PARAM1;
+
+			/* No disabling the command output channel */
+			channel_mask = m | CC_MASK(CC_COMMAND);
+
+			/* TODO: save channel list to EEPROM */
+
+			return EC_SUCCESS;
+		}
 	}
 
 	/* Print the list of channels */
@@ -108,6 +119,6 @@ static int command_ch(int argc, char **argv)
 	return EC_SUCCESS;
 };
 DECLARE_CONSOLE_COMMAND(chan, command_ch,
-			"[mask]",
-			"Get or set console channel mask",
+			"[ save | restore | <mask> ]",
+			"Save, restore, get or set console channel mask",
 			NULL);