azalea: return valid os percentage (#945)

Signed-off-by: LeilaCY-Lin <LeilaCY_Lin@compal.com>

Author: LeilaCY-Lin

zephyr/program/lotus/azalea/src/battery.c

@@ -52,10 +52,17 @@ enum battery_present battery_is_present(void)
 
 uint32_t get_system_percentage(void)
 {
+	static uint32_t pre_os_percentage;
 	uint32_t memmap_cap = *(uint32_t *)host_get_memmap(EC_MEMMAP_BATT_CAP);
 	uint32_t memmap_lfcc = *(uint32_t *)host_get_memmap(EC_MEMMAP_BATT_LFCC);
-
-	return 1000 * memmap_cap / (memmap_lfcc + 1);
+	uint32_t os_percentage = 1000 * memmap_cap / (memmap_lfcc + 1);
+
+	/* ensure this value is valid */
+	if (os_percentage <= 1000 && os_percentage >= 0) {
+		pre_os_percentage = os_percentage;
+		return os_percentage;
+	} else
+		return pre_os_percentage;
 }
 
 static void battery_percentage_control(void)