pd: select dynamically Rp value

Add API to switch the Rp pull-up value on CC dynamically at runtime.
This is a preparatory work for boards having a more complex maximum
source current policy (eg 2 ports sharing a common pool of power).

For fusb302, update the voltage thresholds for open/Rd/Ra as they depend
on the Rp (was missing from the previous change).

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

BRANCH=none
BUG=chrome-os-partner:56110
TEST=make buildall

Change-Id: Id3c24a31a16217075a398ec21ef58ee07187a882
Reviewed-on: https://chromium-review.googlesource.com/373501
Commit-Ready: Vincent Palatin <vpalatin@chromium.org>
Tested-by: Vincent Palatin <vpalatin@chromium.org>
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>

9 files changed, 163 insertions, 84 deletions

diff --git a/driver/tcpm/anx74xx.c b/driver/tcpm/anx74xx.c
index 0465a5179e..d229f37e12 100644
--- a/driver/tcpm/anx74xx.c
+++ b/driver/tcpm/anx74xx.c
@@ -436,6 +436,36 @@ static int anx74xx_tcpm_get_cc(int port, int *cc1, int *cc2)
 	return EC_SUCCESS;
 }
 
+static int anx74xx_tcpm_select_rp_value(int port, int rp)
+{
+	int reg;
+	int rv;
+
+	rv = tcpc_read(port, ANX74XX_REG_ANALOG_CTRL_6, &reg);
+	if (rv)
+		return EC_ERROR_UNKNOWN;
+
+	/* clear Bit[0,1] R_RP to default Rp's value */
+	reg &= ~0x03;
+
+	switch (rp) {
+	case TYPEC_RP_1A5:
+		/* Set Rp strength to 12K for presenting 1.5A */
+		reg |= ANX74XX_REG_CC_PULL_RP_12K;
+		break;
+	case TYPEC_RP_3A0:
+		/* Set Rp strength to 4K for presenting 3A */
+		reg |= ANX74XX_REG_CC_PULL_RP_4K;
+		break;
+	case TYPEC_RP_USB:
+	default:
+		/* default: Set Rp strength to 36K */
+		break;
+	}
+
+	return tcpc_write(port, ANX74XX_REG_ANALOG_CTRL_6, reg);
+}
+
 static int anx74xx_tcpm_set_cc(int port, int pull)
 {
 	int rv = EC_SUCCESS;
@@ -592,36 +622,17 @@ static int anx74xx_alert_status(int port, int *alert)
 
 static int anx74xx_tcpm_set_rx_enable(int port, int enable)
 {
-	int reg, rv = 0;
+	int reg, rv;
 
-	rv |= tcpc_read(port, ANX74XX_REG_IRQ_SOURCE_RECV_MSG_MASK, &reg);
+	rv = tcpc_read(port, ANX74XX_REG_IRQ_SOURCE_RECV_MSG_MASK, &reg);
+	if (rv)
+		return rv;
 	if (enable)
 		reg &= ~(ANX74XX_REG_IRQ_CC_MSG_INT);
 	else/* Disable RX message by masking interrupt */
 		reg |= (ANX74XX_REG_IRQ_CC_MSG_INT);
 	anx74xx_tcpm_set_auto_good_crc(port, enable);
-	rv |= tcpc_write(port, ANX74XX_REG_IRQ_SOURCE_RECV_MSG_MASK, reg);
-
-	/* patch for Rp 36K issue */
-	rv |= tcpc_read(port, ANX74XX_REG_ANALOG_CTRL_6, &reg);
-	if (rv)
-		return EC_ERROR_UNKNOWN;
-
-	/* clear Bit[0,1] R_RP to default Rp's value */
-	reg &= ~0x03;
-
-	if (enable) {
-#ifdef CONFIG_USB_PD_PULLUP_1_5A
-		/* Set Rp strength to 12K for presenting 1.5A */
-		reg |= ANX74XX_REG_CC_PULL_RP_12K;
-#elif defined(CONFIG_USB_PD_PULLUP_3A)
-		/* Set Rp strength to 4K for presenting 3A */
-		reg |= ANX74XX_REG_CC_PULL_RP_4K;
-#endif
-	}
-	rv |= tcpc_write(port, ANX74XX_REG_ANALOG_CTRL_6, reg);
-
-	return rv;
+	return tcpc_write(port, ANX74XX_REG_IRQ_SOURCE_RECV_MSG_MASK, reg);
 }
 
 #ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
@@ -830,6 +841,7 @@ const struct tcpm_drv anx74xx_tcpm_drv = {
 #ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
 	.get_vbus_level		= &anx74xx_tcpm_get_vbus_level,
 #endif
+	.select_rp_value	= &anx74xx_tcpm_select_rp_value,
 	.set_cc			= &anx74xx_tcpm_set_cc,
 	.set_polarity		= &anx74xx_tcpm_set_polarity,
 	.set_vconn		= &anx74xx_tcpm_set_vconn,
diff --git a/driver/tcpm/anx7688.c b/driver/tcpm/anx7688.c
index ae1dd32124..7dda345302 100644
--- a/driver/tcpm/anx7688.c
+++ b/driver/tcpm/anx7688.c
@@ -182,6 +182,7 @@ const struct tcpm_drv anx7688_tcpm_drv = {
 #ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
 	.get_vbus_level		= &anx7688_tcpm_get_vbus_level,
 #endif
+	.select_rp_value	= &tcpci_tcpm_select_rp_value,
 	.set_cc			= &tcpci_tcpm_set_cc,
 	.set_polarity		= &tcpci_tcpm_set_polarity,
 	.set_vconn		= &tcpci_tcpm_set_vconn,
diff --git a/driver/tcpm/fusb302.c b/driver/tcpm/fusb302.c
index a174e5193e..4493adff52 100644
--- a/driver/tcpm/fusb302.c
+++ b/driver/tcpm/fusb302.c
@@ -30,6 +30,8 @@ static struct fusb302_chip_state {
 	int tx_hard_reset_req;
 	int device_id;
 	struct mutex set_cc_lock;
+	uint8_t mdac_vnc;
+	uint8_t mdac_rd;
 } state[CONFIG_USB_PD_PORT_COUNT];
 
 /* bring the FUSB302 out of reset after Hard Reset signaling */
@@ -100,7 +102,6 @@ static int measure_cc_pin_source(int port, int cc_measure)
 	int switches0_reg;
 	int reg;
 	int cc_lvl;
-	int bc_lvl;
 
 	/* Read status register */
 	tcpc_read(port, TCPC_REG_SWITCHES0, &reg);
@@ -119,8 +120,8 @@ static int measure_cc_pin_source(int port, int cc_measure)
 	/* Set measurement switch */
 	tcpc_write(port, TCPC_REG_SWITCHES0, reg);
 
-	/* Set MDAC for Open vs Rd/Ra comparison (~1.6V) */
-	tcpc_write(port, TCPC_REG_MEASURE, 0x26);
+	/* Set MDAC for Open vs Rd/Ra comparison */
+	tcpc_write(port, TCPC_REG_MEASURE, state[port].mdac_vnc);
 
 	/* Wait on measurement */
 	usleep(250);
@@ -131,16 +132,19 @@ static int measure_cc_pin_source(int port, int cc_measure)
 	/* Assume open */
 	cc_lvl = TYPEC_CC_VOLT_OPEN;
 
+	/* CC level is below the 'no connect' threshold (vOpen) */
 	if ((reg & TCPC_REG_STATUS0_COMP) == 0) {
-		/*
-		 * CC line is < 1.6V, now need to determine if Rd or Ra is
-		 * attached. The Ra threshold is < 200 mV and so can use the
-		 * bc_lvl field of STATUS0 register.
-		 */
-		bc_lvl = reg & (TCPC_REG_STATUS0_BC_LVL1 |
-				TCPC_REG_STATUS0_BC_LVL0);
+		/* Set MDAC for Rd vs Ra comparison */
+		tcpc_write(port, TCPC_REG_MEASURE, state[port].mdac_rd);
+
+		/* Wait on measurement */
+		usleep(250);
 
-		cc_lvl = bc_lvl ? TYPEC_CC_VOLT_RD : TYPEC_CC_VOLT_RA;
+		/* Read status register */
+		tcpc_read(port, TCPC_REG_STATUS0, &reg);
+
+		cc_lvl = (reg & TCPC_REG_STATUS0_COMP) ? TYPEC_CC_VOLT_RD
+						       : TYPEC_CC_VOLT_RA;
 	}
 
 	/* Restore SWITCHES0 register to its value prior */
@@ -339,6 +343,40 @@ static int fusb302_send_message(int port, uint16_t header, const uint32_t *data,
 	return rv;
 }
 
+static int fusb302_tcpm_select_rp_value(int port, int rp)
+{
+	int reg;
+	int rv;
+	uint8_t vnc, rd;
+
+	rv = tcpc_read(port, TCPC_REG_CONTROL0, &reg);
+	if (rv)
+		return rv;
+
+	/* Set the current source for Rp value */
+	reg &= ~TCPC_REG_CONTROL0_HOST_CUR_MASK;
+	switch (rp) {
+	case TYPEC_RP_1A5:
+		reg |= TCPC_REG_CONTROL0_HOST_CUR_1A5;
+		vnc = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_1_5_VNC_MV);
+		rd = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_1_5_RD_THRESH_MV);
+		break;
+	case TYPEC_RP_3A0:
+		reg |= TCPC_REG_CONTROL0_HOST_CUR_3A0;
+		vnc = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_3_0_VNC_MV);
+		rd = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_3_0_RD_THRESH_MV);
+		break;
+	case TYPEC_RP_USB:
+	default:
+		reg |= TCPC_REG_CONTROL0_HOST_CUR_USB;
+		vnc = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_DEF_VNC_MV);
+		rd = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_DEF_RD_THRESH_MV);
+	}
+	state[port].mdac_vnc = vnc;
+	state[port].mdac_rd = rd;
+	return tcpc_write(port, TCPC_REG_CONTROL0, reg);
+}
+
 static int fusb302_tcpm_init(int port)
 {
 	int reg;
@@ -347,6 +385,10 @@ static int fusb302_tcpm_init(int port)
 	state[port].cc_polarity = -1;
 
 	state[port].previous_pull = TYPEC_CC_RD;
+	/* set the voltage threshold for no connect detection (vOpen) */
+	state[port].mdac_vnc = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_DEF_VNC_MV);
+	/* set the voltage threshold for Rd vs Ra detection */
+	state[port].mdac_rd = TCPC_REG_MEASURE_MDAC_MV(PD_SRC_DEF_RD_THRESH_MV);
 
 	/* all other variables assumed to default to 0 */
 
@@ -397,15 +439,6 @@ static int fusb302_tcpm_init(int port)
 	/* Interrupt Enable */
 	tcpc_read(port, TCPC_REG_CONTROL0, &reg);
 	reg &= ~TCPC_REG_CONTROL0_INT_MASK;
-	/* Set the current source for Rp value */
-	reg &= ~TCPC_REG_CONTROL0_HOST_CUR_MASK;
-#ifdef CONFIG_USB_PD_PULLUP_1_5A
-	reg |= TCPC_REG_CONTROL0_HOST_CUR_1A5;
-#elif defined(CONFIG_USB_PD_PULLUP_3A)
-	reg |= TCPC_REG_CONTROL0_HOST_CUR_3A0;
-#else
-	reg |= TCPC_REG_CONTROL0_HOST_CUR_USB;
-#endif
 	tcpc_write(port, TCPC_REG_CONTROL0, reg);
 
 	/* Set VCONN switch defaults */
@@ -468,12 +501,6 @@ static int fusb302_tcpm_set_cc(int port, int pull)
 	case TYPEC_CC_RP:
 
 		/* Only use autodetect feature for revA silicon */
-		/*
-		 * TODO(crosbug.com/p/54452): Add configuration of Rp strength
-		 * values for presenting desired current to port partner.
-		 * This value will depend on config flags
-		 * CONFIG_USB_PD_PULLUP_* in the board file
-		 */
 		/* if fusb302 hasn't figured anything out yet */
 		if ((state[port].device_id == FUSB302_DEVID_302A) &&
 		    !state[port].togdone_pullup_cc1 &&
@@ -1032,6 +1059,7 @@ const struct tcpm_drv fusb302_tcpm_drv = {
 #ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
 	.get_vbus_level		= &fusb302_tcpm_get_vbus_level,
 #endif
+	.select_rp_value	= &fusb302_tcpm_select_rp_value,
 	.set_cc			= &fusb302_tcpm_set_cc,
 	.set_polarity		= &fusb302_tcpm_set_polarity,
 	.set_vconn		= &fusb302_tcpm_set_vconn,
diff --git a/driver/tcpm/fusb302.h b/driver/tcpm/fusb302.h
index edf8c3fdf8..dc191bee5a 100644
--- a/driver/tcpm/fusb302.h
+++ b/driver/tcpm/fusb302.h
@@ -50,12 +50,7 @@
 
 #define TCPC_REG_MEASURE	0x04
 #define TCPC_REG_MEASURE_VBUS		(1<<6)
-#define TCPC_REG_MEASURE_MDAC5		(1<<5)
-#define TCPC_REG_MEASURE_MDAC4		(1<<4)
-#define TCPC_REG_MEASURE_MDAC3		(1<<3)
-#define TCPC_REG_MEASURE_MDAC2		(1<<2)
-#define TCPC_REG_MEASURE_MDAC1		(1<<1)
-#define TCPC_REG_MEASURE_MDAC0		(1<<0)
+#define TCPC_REG_MEASURE_MDAC_MV(mv)	(((mv)/42) & 0x3f)
 
 #define TCPC_REG_CONTROL0	0x06
 #define TCPC_REG_CONTROL0_TX_FLUSH	(1<<6)
diff --git a/driver/tcpm/it83xx.c b/driver/tcpm/it83xx.c
index f7bdf5b60b..c3ac8fb49d 100644
--- a/driver/tcpm/it83xx.c
+++ b/driver/tcpm/it83xx.c
@@ -274,23 +274,7 @@ static void it83xx_init(enum usbpd_port port, int role)
 	/* W/C status */
 	IT83XX_USBPD_ISR(port) = 0xff;
 	/* enable cc, select cc1 and Rd. */
-	/*
-	 * bit[3-2]: CC output current (when Rp selected)
-	 *       00: reserved
-	 *       01: 330uA outpt (3.0A)
-	 *       10: 180uA outpt (1.5A)
-	 *       11: 80uA outpt  (USB default)
-	 */
-#ifdef CONFIG_USB_PD_PULLUP_1_5A
-	/* (Rp 1.5A when selected) */
-	IT83XX_USBPD_CCGCR(port) = 0x9;
-#elif defined(CONFIG_USB_PD_PULLUP_3A)
-	/* (Rp 3.0A when selected) */
-	IT83XX_USBPD_CCGCR(port) = 0x5;
-#else
-	/* (Rp default when selected) */
 	IT83XX_USBPD_CCGCR(port) = 0xd;
-#endif
 	/* change data role as the same power role */
 	it83xx_set_data_role(port, role);
 	/* set power role */
@@ -349,6 +333,31 @@ static int it83xx_tcpm_get_cc(int port, int *cc1, int *cc2)
 	return EC_SUCCESS;
 }
 
+static int it83xx_tcpm_select_rp_value(int port, int rp)
+{
+	uint8_t rp;
+	/*
+	 * bit[3-2]: CC output current (when Rp selected)
+	 *       00: reserved
+	 *       01: 330uA outpt (3.0A)
+	 *       10: 180uA outpt (1.5A)
+	 *       11: 80uA outpt  (USB default)
+	 */
+	switch (rp) {
+	case TYPEC_RP_1A5:
+		rp = 2 << 2;
+		break;
+	case TYPEC_RP_3A0:
+		rp = 1 << 2;
+		break;
+	case TYPEC_RP_USB:
+	default:
+		rp = 3 << 2;
+		break;
+	}
+	IT83XX_USBPD_CCGCR(port) = (IT83XX_USBPD_CCGCR(port) & ~(3 << 2)) | Rp;
+}
+
 static int it83xx_tcpm_set_cc(int port, int pull)
 {
 	it83xx_set_cc(port, pull);
@@ -459,6 +468,7 @@ const struct tcpm_drv it83xx_tcpm_drv = {
 #ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
 	.get_vbus_level		= NULL,
 #endif
+	.select_rp_value	= &it83xx_tcpm_select_rp_value,
 	.set_cc			= &it83xx_tcpm_set_cc,
 	.set_polarity		= &it83xx_tcpm_set_polarity,
 	.set_vconn		= &it83xx_tcpm_set_vconn,
diff --git a/driver/tcpm/stub.c b/driver/tcpm/stub.c
index 91ac6638d7..ae3f00f420 100644
--- a/driver/tcpm/stub.c
+++ b/driver/tcpm/stub.c
@@ -66,6 +66,11 @@ int tcpm_get_cc(int port, int *cc1, int *cc2)
 	return tcpc_get_cc(port, cc1, cc2);
 }
 
+int tcpm_select_rp_value(int port, int rp)
+{
+	return -EC_ERROR_UNIMPLEMENTED;
+}
+
 int tcpm_set_cc(int port, int pull)
 {
 	return tcpc_set_cc(port, pull);
diff --git a/driver/tcpm/tcpci.c b/driver/tcpm/tcpci.c
index 14ab07769a..c4600792b0 100644
--- a/driver/tcpm/tcpci.c
+++ b/driver/tcpm/tcpci.c
@@ -85,23 +85,32 @@ static int tcpci_tcpm_get_power_status(int port, int *status)
 	return tcpc_read(port, TCPC_REG_POWER_STATUS, status);
 }
 
+int tcpci_tcpm_select_rp_value(int port, int rp)
+{
+	int reg;
+	int rv;
+
+	rv = tcpc_read(port, TCPC_REG_ROLE_CTRL, &reg);
+	if (rv)
+		return rv;
+	reg = (reg & ~TCPC_REG_ROLE_CTRL_RP_MASK)
+	    | ((rp << 4) & TCPC_REG_ROLE_CTRL_RP_MASK);
+	return tcpc_write(port, TCPC_REG_ROLE_CTRL, reg);
+}
+
 int tcpci_tcpm_set_cc(int port, int pull)
 {
-	uint8_t rp = 0;
+	int reg, rv;
+	uint8_t rp;
+
+	rv = tcpc_read(port, TCPC_REG_ROLE_CTRL, &reg);
+	if (rv)
+		return rv;
+	rp = TCPC_REG_ROLE_CTRL_RP(reg);
 	/*
 	 * Set manual control of Rp/Rd, and set both CC lines to the same
-	 * pull. Set desired Rp strength:
-	 * 00: Rp default
-	 * 01: Rp 1.5A
-	 * 10: Rp 3.0A
-	 * 11: Reserved
+	 * pull.
 	 */
-#ifdef CONFIG_USB_PD_PULLUP_1_5A
-	rp = 0x01;
-#elif defined(CONFIG_USB_PD_PULLUP_3A)
-	rp = 0x02;
-#endif
-
 	return tcpc_write(port, TCPC_REG_ROLE_CTRL,
 			  TCPC_REG_ROLE_CTRL_SET(0, rp, pull, pull));
 }
@@ -366,6 +375,7 @@ const struct tcpm_drv tcpci_tcpm_drv = {
 #ifdef CONFIG_USB_PD_VBUS_DETECT_TCPC
 	.get_vbus_level		= &tcpci_tcpm_get_vbus_level,
 #endif
+	.select_rp_value	= &tcpci_tcpm_select_rp_value,
 	.set_cc			= &tcpci_tcpm_set_cc,
 	.set_polarity		= &tcpci_tcpm_set_polarity,
 	.set_vconn		= &tcpci_tcpm_set_vconn,
diff --git a/driver/tcpm/tcpci.h b/driver/tcpm/tcpci.h
index 1417640a26..88f7030929 100644
--- a/driver/tcpm/tcpci.h
+++ b/driver/tcpm/tcpci.h
@@ -54,6 +54,8 @@
 #define TCPC_REG_ROLE_CTRL         0x1a
 #define TCPC_REG_ROLE_CTRL_SET(drp, rp, cc1, cc2) \
 		((drp) << 6 | (rp) << 4 | (cc2) << 2 | (cc1))
+#define TCPC_REG_ROLE_CTRL_RP_MASK  0x30
+#define TCPC_REG_ROLE_CTRL_RP(reg)  (((reg) & TCPC_REG_ROLE_CTRL_RP_MASK) >> 4)
 #define TCPC_REG_ROLE_CTRL_CC2(reg) (((reg) & 0xc) >> 2)
 #define TCPC_REG_ROLE_CTRL_CC1(reg) ((reg) & 0x3)
 
@@ -117,6 +119,7 @@ extern const struct usb_mux_driver tcpci_tcpm_usb_mux_driver;
 
 int tcpci_tcpm_get_cc(int port, int *cc1, int *cc2);
 int tcpci_tcpm_get_vbus_level(int port);
+int tcpci_tcpm_select_rp_value(int port, int rp);
 int tcpci_tcpm_set_cc(int port, int pull);
 int tcpci_tcpm_set_polarity(int port, int polarity);
 int tcpci_tcpm_set_vconn(int port, int enable);
diff --git a/driver/tcpm/tcpm.h b/driver/tcpm/tcpm.h
index 16cf879f72..b0398f85b1 100644
--- a/driver/tcpm/tcpm.h
+++ b/driver/tcpm/tcpm.h
@@ -78,6 +78,11 @@ static inline int tcpm_get_vbus_level(int port)
 	return tcpc_config[port].drv->get_vbus_level(port);
 }
 
+static inline int tcpm_select_rp_value(int port, int rp)
+{
+	return tcpc_config[port].drv->select_rp_value(port, rp);
+}
+
 static inline int tcpm_set_cc(int port, int pull)
 {
 	return tcpc_config[port].drv->set_cc(port, pull);
@@ -152,6 +157,16 @@ int tcpm_get_cc(int port, int *cc1, int *cc2);
 int tcpm_get_vbus_level(int port);
 
 /**
+ * Set the value of the CC pull-up used when we are a source.
+ *
+ * @param port Type-C port number
+ * @param rp One of enum tcpc_rp_value
+ *
+ * @return EC_SUCCESS or error
+ */
+int tcpm_select_rp_value(int port, int rp);
+
+/**
  * Set the CC pull resistor. This sets our role as either source or sink.
  *
  * @param port Type-C port number