pd: send soft reset before an EC reset

Send soft reset to all connected USB PD ports before a user
initiated reset (via console or host command). This fixes a problem
where EC will send PD hard reset to a charger after an EC reboot, which
will cause another reboot if battery is not present.

BUG=chrome-os-partner:44085
BRANCH=none
TEST=tested on glados without a battery. with zinger attached, issue
'reboot' from console and verify that we only reboot once.

Change-Id: Id6c56cda33c289e3425cb433f7fcbe76669d2dff
Signed-off-by: Alec Berg <alecaberg@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/295889
Reviewed-by: Shawn N <shawnn@chromium.org>

3 files changed, 20 insertions, 10 deletions

diff --git a/common/system.c b/common/system.c
index 856f3d981f..42eb91bf71 100644
--- a/common/system.c
+++ b/common/system.c
@@ -440,12 +440,8 @@ static void jump_to_image(uintptr_t init_addr)
 	gpio_set_level(GPIO_ENTERING_RW, 0);
 
 #ifdef CONFIG_USB_POWER_DELIVERY
-	/*
-	 * Notify USB PD module that we are about to sysjump and give it time
-	 * to do what it needs.
-	 */
-	pd_prepare_sysjump();
-	usleep(5*MSEC);
+	/* Notify USB PD module that we are about to reset */
+	pd_prepare_reset();
 #endif
 
 #ifdef CONFIG_I2C
@@ -725,10 +721,15 @@ static int handle_pending_reboot(enum ec_reboot_cmd cmd)
 	case EC_REBOOT_JUMP_RW:
 		return system_run_image_copy(SYSTEM_IMAGE_RW);
 	case EC_REBOOT_COLD:
+#ifdef CONFIG_USB_POWER_DELIVERY
+		/* Notify USB PD module that we are about to reset */
+		pd_prepare_reset();
+#endif
 #ifdef HAS_TASK_PDCMD
 		/* Reboot the PD chip as well */
 		board_reset_pd_mcu();
 #endif
+
 		system_reset(SYSTEM_RESET_HARD);
 		/* That shouldn't return... */
 		return EC_ERROR_UNKNOWN;
@@ -918,6 +919,12 @@ static int command_reboot(int argc, char **argv)
 		ccputs("Hard-");
 	ccputs("Rebooting!\n\n\n");
 	cflush();
+
+#ifdef CONFIG_USB_POWER_DELIVERY
+	/* Notify USB PD module that we are about to reset */
+	pd_prepare_reset();
+#endif
+
 	system_reset(flags);
 	return EC_SUCCESS;
 }
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index b6507baa5c..07ce8189dc 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -558,12 +558,12 @@ void pd_soft_reset(void)
 		}
 }
 
-void pd_prepare_sysjump(void)
+void pd_prepare_reset(void)
 {
 	int i;
 
 	/*
-	 * On sysjump, we are most definitely going to drop pings (if any)
+	 * On reset, we are most definitely going to drop pings (if any)
 	 * and lose all of our PD state. Instead of trying to remember all
 	 * the states and deal with on-going transmission, let's send soft
 	 * reset here and then disable PD communication until after sysjump
@@ -575,6 +575,9 @@ void pd_prepare_sysjump(void)
 			pd[i].flags |= PD_FLAGS_SFT_RST_DIS_COMM;
 
 	pd_soft_reset();
+
+	/* Give time for soft reset to be sent */
+	usleep(5*MSEC);
 }
 
 #ifdef CONFIG_USB_PD_DUAL_ROLE
diff --git a/include/usb_pd.h b/include/usb_pd.h
index 6ca88bb55a..5a67965853 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -1502,8 +1502,8 @@ void pd_ping_enable(int port, int enable);
 /* Issue PD soft reset */
 void pd_soft_reset(void);
 
-/* Prepare PD communication for sysjump */
-void pd_prepare_sysjump(void);
+/* Prepare PD communication for reset */
+void pd_prepare_reset(void);
 
 /**
  * Signal power request to indicate a charger update that affects the port.