pd: wait tSnkTransition after ACCEPT to change voltage

Ensure that the PD source changes the output voltage after
tSnkTransition delay after having sent the ACCEPT message
(rather than before).

Signed-off-by: Vincent Palatin <vpalatin@chromium.org>

BRANCH=samus
BUG=chrome-os-partner:33684
TEST=connect Zinger to a PD power sink and monitor VBUS and CC while
doing a 20V to 5V transition.

Change-Id: If86f59eec67630491f4e8dc13a52015ac2de918a
Reviewed-on: https://chromium-review.googlesource.com/230805
Reviewed-by: Alec Berg <alecaberg@chromium.org>
Commit-Queue: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>

11 files changed, 74 insertions, 29 deletions

diff --git a/board/dingdong/usb_pd_policy.c b/board/dingdong/usb_pd_policy.c
index 63223d8927..2743eb12fd 100644
--- a/board/dingdong/usb_pd_policy.c
+++ b/board/dingdong/usb_pd_policy.c
@@ -96,12 +96,16 @@ void pd_set_max_voltage(unsigned mv)
 	select_mv = mv;
 }
 
-int requested_voltage_idx;
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No operation: sink only */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	return EC_SUCCESS;
diff --git a/board/firefly/usb_pd_policy.c b/board/firefly/usb_pd_policy.c
index 4a04988290..07b8e7745d 100644
--- a/board/firefly/usb_pd_policy.c
+++ b/board/firefly/usb_pd_policy.c
@@ -97,12 +97,17 @@ void pd_set_max_voltage(unsigned mv)
 	select_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	/* Never acting as a source */
 	return EC_ERROR_INVAL;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No operation: sink only */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* Never acting as a source */
diff --git a/board/fruitpie/usb_pd_policy.c b/board/fruitpie/usb_pd_policy.c
index fcc25d1345..52adce5677 100644
--- a/board/fruitpie/usb_pd_policy.c
+++ b/board/fruitpie/usb_pd_policy.c
@@ -98,7 +98,7 @@ void pd_set_max_voltage(unsigned mv)
 	max_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -117,13 +117,18 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		 ((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		 ((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No-operation: we are always 5V */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* provide VBUS */
diff --git a/board/hoho/usb_pd_policy.c b/board/hoho/usb_pd_policy.c
index 6098c790c1..a2d35f6e58 100644
--- a/board/hoho/usb_pd_policy.c
+++ b/board/hoho/usb_pd_policy.c
@@ -96,12 +96,16 @@ void pd_set_max_voltage(unsigned mv)
 	select_mv = mv;
 }
 
-int requested_voltage_idx;
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No operation: sink only */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	return EC_SUCCESS;
diff --git a/board/host/usb_pd_policy.c b/board/host/usb_pd_policy.c
index 6432e0ae7b..423add3543 100644
--- a/board/host/usb_pd_policy.c
+++ b/board/host/usb_pd_policy.c
@@ -97,7 +97,7 @@ void pd_set_max_voltage(unsigned mv)
 	max_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -116,13 +116,18 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* Not implemented */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* Not implemented */
diff --git a/board/plankton/usb_pd_policy.c b/board/plankton/usb_pd_policy.c
index b2fb708888..ad691f6187 100644
--- a/board/plankton/usb_pd_policy.c
+++ b/board/plankton/usb_pd_policy.c
@@ -117,8 +117,7 @@ void pd_set_max_voltage(unsigned mv)
 	select_mv = mv;
 }
 
-int requested_voltage_idx;
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -137,21 +136,23 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
-	requested_voltage_idx = idx;
-
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	gpio_set_level(GPIO_USBC_VSEL_0, idx >= 2);
+	gpio_set_level(GPIO_USBC_VSEL_1, idx >= 3);
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* Output the correct voltage */
 	gpio_set_level(GPIO_VBUS_CHARGER_EN, 1);
-	gpio_set_level(GPIO_USBC_VSEL_0, requested_voltage_idx >= 2);
-	gpio_set_level(GPIO_USBC_VSEL_1, requested_voltage_idx >= 3);
 
 	return EC_SUCCESS;
 }
@@ -159,7 +160,6 @@ int pd_set_power_supply_ready(int port)
 void pd_power_supply_reset(int port)
 {
 	/* Kill VBUS */
-	requested_voltage_idx = 0;
 	gpio_set_level(GPIO_VBUS_CHARGER_EN, 0);
 	gpio_set_level(GPIO_USBC_VSEL_0, 0);
 	gpio_set_level(GPIO_USBC_VSEL_1, 0);
diff --git a/board/ryu/usb_pd_policy.c b/board/ryu/usb_pd_policy.c
index aea73188d4..cc8979e6f8 100644
--- a/board/ryu/usb_pd_policy.c
+++ b/board/ryu/usb_pd_policy.c
@@ -113,7 +113,7 @@ void pd_set_max_voltage(unsigned mv)
 	max_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -132,13 +132,18 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No-operation: we are always 5V */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* provide VBUS */
diff --git a/board/ryu_p1/usb_pd_policy.c b/board/ryu_p1/usb_pd_policy.c
index 9ee61dde65..d98d17c11c 100644
--- a/board/ryu_p1/usb_pd_policy.c
+++ b/board/ryu_p1/usb_pd_policy.c
@@ -113,7 +113,7 @@ void pd_set_max_voltage(unsigned mv)
 	max_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -132,13 +132,18 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No-operation: we are always 5V */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* provide VBUS */
diff --git a/board/samus_pd/usb_pd_policy.c b/board/samus_pd/usb_pd_policy.c
index 036653af9a..b87c880ded 100644
--- a/board/samus_pd/usb_pd_policy.c
+++ b/board/samus_pd/usb_pd_policy.c
@@ -131,7 +131,7 @@ void pd_set_max_voltage(unsigned mv)
 	max_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -150,13 +150,18 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		 ((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		 ((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+	/* No-operation: we are always 5V */
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	/* provide VBUS */
diff --git a/board/twinkie/usb_pd_policy.c b/board/twinkie/usb_pd_policy.c
index ec59b82769..31856c907c 100644
--- a/board/twinkie/usb_pd_policy.c
+++ b/board/twinkie/usb_pd_policy.c
@@ -116,7 +116,7 @@ void pd_set_max_voltage(unsigned mv)
 	max_mv = mv;
 }
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -135,13 +135,17 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	CPRINTF("Switch to %d V %d mA (for %d/%d mA)\n",
+	CPRINTF("Requested %d V %d mA (for %d/%d mA)\n",
 		((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
 
 	return EC_SUCCESS;
 }
 
+void pd_transition_voltage(int idx)
+{
+}
+
 int pd_set_power_supply_ready(int port)
 {
 	return EC_SUCCESS; /* we are ready */
diff --git a/board/zinger/usb_pd_policy.c b/board/zinger/usb_pd_policy.c
index 2c609eca2b..de8104fea5 100644
--- a/board/zinger/usb_pd_policy.c
+++ b/board/zinger/usb_pd_policy.c
@@ -180,7 +180,7 @@ static int last_volt_idx;
 /* output current measurement */
 int vbus_amp;
 
-int pd_request_voltage(uint32_t rdo)
+int pd_check_requested_voltage(uint32_t rdo)
 {
 	int op_ma = rdo & 0x3FF;
 	int max_ma = (rdo >> 10) & 0x3FF;
@@ -203,10 +203,15 @@ int pd_request_voltage(uint32_t rdo)
 	if (max_ma > pdo_ma)
 		return EC_ERROR_INVAL; /* too much max current */
 
-	debug_printf("Switch to %d V %d mA (for %d/%d mA)\n",
+	debug_printf("Requested %d V %d mA (for %d/%d mA)\n",
 		     ((pdo >> 10) & 0x3ff) * 50, (pdo & 0x3ff) * 10,
 		     ((rdo >> 10) & 0x3ff) * 10, (rdo & 0x3ff) * 10);
+	/* Accept the requested voltage */
+	return EC_SUCCESS;
+}
 
+void pd_transition_voltage(int idx)
+{
 	if (idx - 1 < volt_idx) { /* down voltage transition */
 		/* Stop OCP monitoring */
 		adc_disable_watchdog();
@@ -224,8 +229,6 @@ int pd_request_voltage(uint32_t rdo)
 	last_volt_idx = volt_idx;
 	volt_idx = idx - 1;
 	set_output_voltage(voltages[volt_idx].select);
-
-	return EC_SUCCESS;
 }
 
 int pd_set_power_supply_ready(int port)