Re: [PATCH v1] usb: typec: tcpci: Fix up sink disconnect thresholds for PD
From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Date: 2021-06-16 13:41:08
Also in:
lkml, stable
On Tue, Jun 15, 2021 at 10:43:23AM -0700, Badhri Jagan Sridharan wrote:
"Table 4-3 VBUS Sink Characteristics" of "Type-C Cable and Connector
Specification" defines the disconnect voltage thresholds of various
configurations. This change fixes the disconnect threshold voltage
calculation based on vSinkPD_min and vSinkDisconnectPD as defined
by the table.
Fixes: e1a97bf80a022 ("usb: typec: tcpci: Implement Auto discharge disconnect callbacks")
Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
quoted hunk ↗ jump to hunk
--- drivers/usb/typec/tcpm/tcpci.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c index 22862345d1ab..9858716698df 100644 --- a/drivers/usb/typec/tcpm/tcpci.c +++ b/drivers/usb/typec/tcpm/tcpci.c@@ -21,8 +21,12 @@ #define PD_RETRY_COUNT_DEFAULT 3 #define PD_RETRY_COUNT_3_0_OR_HIGHER 2 #define AUTO_DISCHARGE_DEFAULT_THRESHOLD_MV 3500 -#define AUTO_DISCHARGE_PD_HEADROOM_MV 850 -#define AUTO_DISCHARGE_PPS_HEADROOM_MV 1250 +#define VSINKPD_MIN_IR_DROP_MV 750 +#define VSRC_NEW_MIN_PERCENT 95 +#define VSRC_VALID_MIN_MV 500 +#define VPPS_NEW_MIN_PERCENT 95 +#define VPPS_VALID_MIN_MV 100 +#define VSINKDISCONNECT_PD_MIN_PERCENT 90 #define tcpc_presenting_rd(reg, cc) \ (!(TCPC_ROLE_CTRL_DRP & (reg)) && \@@ -351,11 +355,13 @@ static int tcpci_set_auto_vbus_discharge_threshold(struct tcpc_dev *dev, enum ty threshold = AUTO_DISCHARGE_DEFAULT_THRESHOLD_MV; } else if (mode == TYPEC_PWR_MODE_PD) { if (pps_active) - threshold = (95 * requested_vbus_voltage_mv / 100) - - AUTO_DISCHARGE_PD_HEADROOM_MV; + threshold = ((VPPS_NEW_MIN_PERCENT * requested_vbus_voltage_mv / 100) - + VSINKPD_MIN_IR_DROP_MV - VPPS_VALID_MIN_MV) * + VSINKDISCONNECT_PD_MIN_PERCENT / 100; else - threshold = (95 * requested_vbus_voltage_mv / 100) - - AUTO_DISCHARGE_PPS_HEADROOM_MV; + threshold = ((VSRC_NEW_MIN_PERCENT * requested_vbus_voltage_mv / 100) - + VSINKPD_MIN_IR_DROP_MV - VSRC_VALID_MIN_MV) * + VSINKDISCONNECT_PD_MIN_PERCENT / 100; } else { /* 3.5V for non-pd sink */ threshold = AUTO_DISCHARGE_DEFAULT_THRESHOLD_MV;-- 2.32.0.272.g935e593368-goog
-- heikki