device: add support for leaving device powered

For some devices it might be desirable to leave device powered on after
the cdba exits (e.g. to run some long-running tests). Add the
'power_always_on' option that tells cdba server to leave device powered
on after exiting and to toggle power (to reset the device) when
connecting.

Signed-off-by: Dmitry Baryshkov <[email protected]>

Author: lumag

device.c

@@ -94,6 +94,8 @@ static bool device_check_access(struct device *device,
 	return false;
 }
 
+static int device_power_off(struct device *device);
+
 struct device *device_open(const char *board,
 			   const char *username)
 {
@@ -132,6 +134,18 @@ struct device *device_open(const char *board,
 	if (!device->console)
 		errx(1, "failed to open device console");
 
+	/*
+	 * Power off before opening fastboot. Otherwise if the device is
+	 * already in the fastboot state, CDBA will detect it, then power up
+	 * procedure will restart the device causing fastboot to disappear and
+	 * appear again. This will cause CDBA to exit, ending up with the
+	 * unbreakable fastboot-reset-second_fastboot-quit cycle.
+	 * */
+	if (device->power_always_on) {
+		device_power_off(device);
+		sleep(2);
+	}
+
 	if (device->usb_always_on)
 		device_usb(device, true);
 
@@ -374,7 +388,8 @@ void device_close(struct device *dev)
 {
 	if (!dev->usb_always_on)
 		device_usb(dev, false);
-	device_power(dev, false);
+	if (!dev->power_always_on)
+		device_power(dev, false);
 
 	if (device_has_control(dev, close))
 		device_control(dev, close);

device.h

@@ -41,6 +41,7 @@ struct device {
 	unsigned voltage;
 	bool tickle_mmc;
 	bool usb_always_on;
+	bool power_always_on;
 	struct fastboot *fastboot;
 	unsigned int fastboot_key_timeout;
 	int state;

device_parser.c

@@ -171,6 +171,8 @@ static void parse_board(struct device_parser *dp)
 			dev->ppps3_path = strdup(value);
 		} else if (!strcmp(key, "status-cmd")) {
 			dev->status_cmd = strdup(value);
+		} else if (!strcmp(key, "power_always_on")) {
+			dev->power_always_on = !strcmp(value, "true");
 		} else {
 			fprintf(stderr, "device parser: unknown key \"%s\"\n", key);
 			exit(1);