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-next 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 also be merged in the next major kernel release
during the merge window.
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
