pd: update policy, timeout and board callbacks

Slightly modify interfaces for better sink-only devices implementation
(eg Firefly)

update the host mode management and the voltage selection
and add a hook for board checks.

Simplify the reception timeout and fix other timeout detections.

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

BRANCH=none
BUG=none
TEST=make buildall
and use with the follow-up firefly board configuration CL.

Change-Id: I0240295764c8605793dc80a2fc21357af1740744
Reviewed-on: https://chromium-review.googlesource.com/195585
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Commit-Queue: Vincent Palatin <vpalatin@chromium.org>

6 files changed, 49 insertions, 28 deletions

diff --git a/board/fruitpie/usb_pd_config.h b/board/fruitpie/usb_pd_config.h
index 59c9852719..cdbb0f365d 100644
--- a/board/fruitpie/usb_pd_config.h
+++ b/board/fruitpie/usb_pd_config.h
@@ -61,6 +61,11 @@ static inline void pd_tx_init(void)
 	gpio_config_module(MODULE_USB_PD, 1);
 }
 
+static inline void pd_set_host_mode(int enable)
+{
+	gpio_set_level(GPIO_CC_HOST, enable);
+}
+
 /* Standard-current DFP : no-connect voltage is 1.55V */
 #define PD_SRC_VNC 1550 /* mV */
 
diff --git a/board/fruitpie/usb_pd_policy.c b/board/fruitpie/usb_pd_policy.c
index ae57559e6b..c756dcc7bd 100644
--- a/board/fruitpie/usb_pd_policy.c
+++ b/board/fruitpie/usb_pd_policy.c
@@ -112,3 +112,7 @@ int pd_set_power_supply_ready(void)
 void pd_power_supply_reset(void)
 {
 }
+
+void pd_board_checks(void)
+{
+}
diff --git a/board/zinger/usb_pd_policy.c b/board/zinger/usb_pd_policy.c
index 5f314185a3..b506c15aec 100644
--- a/board/zinger/usb_pd_policy.c
+++ b/board/zinger/usb_pd_policy.c
@@ -106,3 +106,7 @@ void pd_power_supply_reset(void)
 	set_output_voltage(VO_5V);
 	/* TODO transition delay */
 }
+
+void pd_board_checks(void)
+{
+}
diff --git a/chip/stm32/usb_pd_phy.c b/chip/stm32/usb_pd_phy.c
index a3e78ef0da..2d33e9f96e 100644
--- a/chip/stm32/usb_pd_phy.c
+++ b/chip/stm32/usb_pd_phy.c
@@ -80,10 +80,8 @@ static int wait_bits(int nb)
 
 	avail = dma_bytes_done(rx, PD_MAX_RAW_SIZE);
 	if (avail < nb) { /* no received yet ... */
-		timestamp_t deadline = get_time();
-		deadline.val += 4 * MAX_BITS * (nb - avail);
 		while ((dma_bytes_done(rx, PD_MAX_RAW_SIZE) < nb)
-			&& get_time().val < deadline.val)
+			&& !(STM32_TIM_SR(TIM_RX) & 4))
 			; /* optimized for latency, not CPU usage ... */
 		if (dma_bytes_done(rx, PD_MAX_RAW_SIZE) < nb) {
 			CPRINTF("TMOUT RX %d/%d\n",
@@ -524,10 +522,3 @@ void pd_set_clock(int freq)
 {
 	STM32_TIM_ARR(TIM_TX) = clock_get_freq() / (2*freq);
 }
-
-#ifdef CONFIG_USB_PD_DUAL_ROLE
-void pd_set_host_mode(int enable)
-{
-	gpio_set_level(GPIO_CC_HOST, enable);
-}
-#endif /* CONFIG_USB_PD_DUAL_ROLE */
diff --git a/common/usb_pd_protocol.c b/common/usb_pd_protocol.c
index 4d0ef0f90b..b5c64d83f8 100644
--- a/common/usb_pd_protocol.c
+++ b/common/usb_pd_protocol.c
@@ -305,9 +305,11 @@ static int send_validate_message(void *ctxt, uint16_t header, uint8_t cnt,
 			   id == pd_message_id) {
 				/* got the GoodCRC we were expecting */
 				inc_id();
+				/* do not catch last edges as a new packet */
+				udelay(10);
 				return bit_len;
 			} else {
-				CPRINTF("ERR ACK/%d %04x\n", id, head);
+				/* CPRINTF("ERR ACK/%d %04x\n", id, head); */
 			}
 		}
 	}
@@ -626,6 +628,8 @@ void pd_task(void)
 	while (1) {
 		/* monitor for incoming packet */
 		pd_rx_enable_monitoring();
+		/* Verify board specific health status : current, voltages... */
+		pd_board_checks();
 		/* wait for next event/packet or timeout expiration */
 		evt = task_wait_event(timeout);
 		/* incoming packet ? */
@@ -637,7 +641,8 @@ void pd_task(void)
 			else if (head == PD_ERR_HARD_RESET)
 				execute_hard_reset();
 		}
-		timeout = -1;
+		/* if nothing to do, verify the state of the world in 500ms */
+		timeout = 500*MSEC;
 		switch (pd_task_state) {
 		case PD_STATE_DISABLED:
 			/* Nothing to do */
@@ -719,6 +724,8 @@ void pd_task(void)
 			break;
 		case PD_STATE_SNK_READY:
 			/* we have power and we are happy */
+			/* check vital parameters from time to time */
+			timeout = 100*MSEC;
 			break;
 #endif /* CONFIG_USB_PD_DUAL_ROLE */
 		case PD_STATE_HARD_RESET:
@@ -740,6 +747,15 @@ void pd_rx_event(void)
 }
 
 #ifdef CONFIG_COMMON_RUNTIME
+void pd_request_source_voltage(int mv)
+{
+	pd_set_max_voltage(mv);
+	pd_role = PD_ROLE_SINK;
+	pd_set_host_mode(0);
+	pd_task_state = PD_STATE_SNK_DISCONNECTED;
+	task_wake(TASK_ID_PD);
+}
+
 static int command_pd(int argc, char **argv)
 {
 	if (argc < 2)
@@ -759,18 +775,12 @@ static int command_pd(int argc, char **argv)
 		pd_task_state = PD_STATE_SRC_DISCONNECTED;
 		task_wake(TASK_ID_PD);
 	} else if (!strncasecmp(argv[1], "dev", 3)) {
+		int max_volt = -1;
 		if (argc >= 3) {
-			unsigned max_volt;
 			char *e;
-
-			max_volt = strtoi(argv[2], &e, 10);
-			pd_set_max_voltage(max_volt * 1000);
+			max_volt = strtoi(argv[2], &e, 10) * 1000;
 		}
-
-		pd_role = PD_ROLE_SINK;
-		pd_set_host_mode(0);
-		pd_task_state = PD_STATE_SNK_DISCONNECTED;
-		task_wake(TASK_ID_PD);
+		pd_request_source_voltage(max_volt);
 	} else if (!strcasecmp(argv[1], "clock")) {
 		int freq;
 		char *e;
diff --git a/include/usb_pd.h b/include/usb_pd.h
index 8c70fe5d50..c3fac8b296 100644
--- a/include/usb_pd.h
+++ b/include/usb_pd.h
@@ -142,6 +142,20 @@ void pd_power_supply_reset(void);
  */
 int pd_set_power_supply_ready(void);
 
+/**
+ * Ask the specified voltage from the PD source.
+ *
+ * It triggers a new negotiation sequence with the source.
+ * @param mv request voltage in millivolts.
+ */
+void pd_request_source_voltage(int mv);
+
+/*
+ * Verify board specific health status : current, voltages...
+ *
+ */
+void pd_board_checks(void);
+
 /* Power Data Objects for the source and the sink */
 extern const uint32_t pd_src_pdo[];
 extern const int pd_src_pdo_cnt;
@@ -224,13 +238,6 @@ void pd_dump_packet(void *ctxt, const char *msg);
  */
 void pd_set_clock(int freq);
 
-/**
- * Enable/Disable the host pull-up on CC.
- *
- * @param enable non null if we are a host / power source.
- */
-void pd_set_host_mode(int enable);
-
 /* TX/RX callbacks */
 
 /**