This is a note to let you know that I've just added the patch titled
usb: typec: tcpci: Fix up sink disconnect thresholds for PD
to my usb git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-testing branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will be merged to the usb-next branch sometime soon,
after it passes testing, and the merge window is open.
If you have any questions about this process, please let me know.
>From 4288debeaa4e21d8dd5132739ffba2d343892bbf Mon Sep 17 00:00:00 2001
From: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
Date: Tue, 15 Jun 2021 10:43:23 -0700
Subject: usb: typec: tcpci: Fix up sink disconnect thresholds for PD
"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")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
Signed-off-by: Badhri Jagan Sridharan <badhri@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210615174323.1160132-1-badhri@xxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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
