usb: typec: ucsi: psy: Set current max to 100mA for BC 1.2 and Default

ucsi_psy_get_current_max would return 0mA as the maximum current if
UCSI detected a BC or a Default USB Power sporce.

The comment in this function is true that we can't tell the difference
between DCP/CDP or SDP chargers, but we can guarantee that at least 1-unit
of USB 1.1/2.0 power is available, which is 100mA, which is a better
fallback value than 0, which causes some userspaces, including the ChromeOS
power manager, to regard this as a power source that is not providing
any power.

In reality, 100mA is guaranteed from all sources in these classes.

Signed-off-by: Benson Leung <[email protected]>
Reviewed-by: Jameson Thies <[email protected]>
Reviewed-by: Heikki Krogerus <[email protected]>
Reviewed-by: Sebastian Reichel <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: bleungatchromium

drivers/usb/typec/ucsi/psy.c

@@ -164,7 +164,7 @@ static int ucsi_psy_get_current_max(struct ucsi_connector *con,
 	case UCSI_CONSTAT_PWR_OPMODE_DEFAULT:
 	/* UCSI can't tell b/w DCP/CDP or USB2/3x1/3x2 SDP chargers */
 	default:
-		val->intval = 0;
+		val->intval = UCSI_TYPEC_DEFAULT_CURRENT * 1000;
 		break;
 	}
 	return 0;

drivers/usb/typec/ucsi/ucsi.h

@@ -483,9 +483,10 @@ struct ucsi {
 #define UCSI_MAX_SVID		5
 #define UCSI_MAX_ALTMODES	(UCSI_MAX_SVID * 6)
 
-#define UCSI_TYPEC_VSAFE5V	5000
-#define UCSI_TYPEC_1_5_CURRENT	1500
-#define UCSI_TYPEC_3_0_CURRENT	3000
+#define UCSI_TYPEC_VSAFE5V		5000
+#define UCSI_TYPEC_DEFAULT_CURRENT	 100
+#define UCSI_TYPEC_1_5_CURRENT		1500
+#define UCSI_TYPEC_3_0_CURRENT		3000
 
 struct ucsi_connector {
 	int num;