From e1a97bf80a022cdd7a5746a7de8e19f02203d112 Mon Sep 17 00:00:00 2001 From: Badhri Jagan Sridharan Date: Wed, 28 Oct 2020 23:31:36 -0700 Subject: [PATCH] usb: typec: tcpci: Implement Auto discharge disconnect callbacks vImplement callbacks for enabling/disabling POWER_CONTROL.AutoDischargeDisconnect. Programs VBUS_SINK_DISCONNECT_THRESHOLD based on the voltage requested as sink, mode of operation. The programmed threshold is based on vSinkDisconnect and vSinkDisconnectPD values. Add auto_discharge_disconnect to tdata to allow TCPC chip level drivers enable AutoDischargeDisconnect. Signed-off-by: Badhri Jagan Sridharan Reviewed-by: Heikki Krogerus Link: https://lore.kernel.org/r/20201029063138.1429760-9-badhri@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/tcpm/tcpci.c | 63 +++++++++++++++++++++++++++++++++++++++++- drivers/usb/typec/tcpm/tcpci.h | 14 ++++++++-- 2 files changed, 74 insertions(+), 3 deletions(-) diff --git a/drivers/usb/typec/tcpm/tcpci.c b/drivers/usb/typec/tcpm/tcpci.c index f91688e..12d983a 100644 --- a/drivers/usb/typec/tcpm/tcpci.c +++ b/drivers/usb/typec/tcpm/tcpci.c @@ -18,7 +18,10 @@ #include "tcpci.h" -#define PD_RETRY_COUNT 3 +#define PD_RETRY_COUNT 3 +#define AUTO_DISCHARGE_DEFAULT_THRESHOLD_MV 3500 +#define AUTO_DISCHARGE_PD_HEADROOM_MV 850 +#define AUTO_DISCHARGE_PPS_HEADROOM_MV 1250 struct tcpci { struct device *dev; @@ -268,6 +271,58 @@ static int tcpci_set_vconn(struct tcpc_dev *tcpc, bool enable) enable ? TCPC_POWER_CTRL_VCONN_ENABLE : 0); } +static int tcpci_enable_auto_vbus_discharge(struct tcpc_dev *dev, bool enable) +{ + struct tcpci *tcpci = tcpc_to_tcpci(dev); + int ret; + + ret = regmap_update_bits(tcpci->regmap, TCPC_POWER_CTRL, TCPC_POWER_CTRL_AUTO_DISCHARGE, + enable ? TCPC_POWER_CTRL_AUTO_DISCHARGE : 0); + return ret; +} + +static int tcpci_set_auto_vbus_discharge_threshold(struct tcpc_dev *dev, enum typec_pwr_opmode mode, + bool pps_active, u32 requested_vbus_voltage_mv) +{ + struct tcpci *tcpci = tcpc_to_tcpci(dev); + unsigned int pwr_ctrl, threshold = 0; + int ret; + + /* + * Indicates that vbus is going to go away due PR_SWAP, hard reset etc. + * Do not discharge vbus here. + */ + if (requested_vbus_voltage_mv == 0) + goto write_thresh; + + ret = regmap_read(tcpci->regmap, TCPC_POWER_CTRL, &pwr_ctrl); + if (ret < 0) + return ret; + + if (pwr_ctrl & TCPC_FAST_ROLE_SWAP_EN) { + /* To prevent disconnect when the source is fast role swap is capable. */ + 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; + else + threshold = (95 * requested_vbus_voltage_mv / 100) - + AUTO_DISCHARGE_PPS_HEADROOM_MV; + } else { + /* 3.5V for non-pd sink */ + threshold = AUTO_DISCHARGE_DEFAULT_THRESHOLD_MV; + } + + threshold = threshold / TCPC_VBUS_SINK_DISCONNECT_THRESH_LSB_MV; + + if (threshold > TCPC_VBUS_SINK_DISCONNECT_THRESH_MAX) + return -EINVAL; + +write_thresh: + return tcpci_write16(tcpci, TCPC_VBUS_SINK_DISCONNECT_THRESH, threshold); +} + static int tcpci_enable_frs(struct tcpc_dev *dev, bool enable) { struct tcpci *tcpci = tcpc_to_tcpci(dev); @@ -638,6 +693,12 @@ struct tcpci *tcpci_register_port(struct device *dev, struct tcpci_data *data) tcpci->tcpc.enable_frs = tcpci_enable_frs; tcpci->tcpc.frs_sourcing_vbus = tcpci_frs_sourcing_vbus; + if (tcpci->data->auto_discharge_disconnect) { + tcpci->tcpc.enable_auto_vbus_discharge = tcpci_enable_auto_vbus_discharge; + tcpci->tcpc.set_auto_vbus_discharge_threshold = + tcpci_set_auto_vbus_discharge_threshold; + } + err = tcpci_parse_config(tcpci); if (err < 0) return ERR_PTR(err); diff --git a/drivers/usb/typec/tcpm/tcpci.h b/drivers/usb/typec/tcpm/tcpci.h index b418fe1..3fe3136 100644 --- a/drivers/usb/typec/tcpm/tcpci.h +++ b/drivers/usb/typec/tcpm/tcpci.h @@ -8,6 +8,8 @@ #ifndef __LINUX_USB_TCPCI_H #define __LINUX_USB_TCPCI_H +#include + #define TCPC_VENDOR_ID 0x0 #define TCPC_PRODUCT_ID 0x2 #define TCPC_BCD_DEV 0x4 @@ -67,6 +69,7 @@ #define TCPC_POWER_CTRL 0x1c #define TCPC_POWER_CTRL_VCONN_ENABLE BIT(0) +#define TCPC_POWER_CTRL_AUTO_DISCHARGE BIT(4) #define TCPC_FAST_ROLE_SWAP_EN BIT(7) #define TCPC_CC_STATUS 0x1d @@ -133,6 +136,8 @@ #define TCPC_VBUS_VOLTAGE 0x70 #define TCPC_VBUS_SINK_DISCONNECT_THRESH 0x72 +#define TCPC_VBUS_SINK_DISCONNECT_THRESH_LSB_MV 25 +#define TCPC_VBUS_SINK_DISCONNECT_THRESH_MAX 0x3ff #define TCPC_VBUS_STOP_DISCHARGE_THRESH 0x74 #define TCPC_VBUS_VOLTAGE_ALARM_HI_CFG 0x76 #define TCPC_VBUS_VOLTAGE_ALARM_LO_CFG 0x78 @@ -140,17 +145,22 @@ /* I2C_WRITE_BYTE_COUNT + 1 when TX_BUF_BYTE_x is only accessible I2C_WRITE_BYTE_COUNT */ #define TCPC_TRANSMIT_BUFFER_MAX_LEN 31 +struct tcpci; + /* - * @TX_BUF_BYTE_x_hidden + * @TX_BUF_BYTE_x_hidden: * optional; Set when TX_BUF_BYTE_x can only be accessed through I2C_WRITE_BYTE_COUNT. * @frs_sourcing_vbus: * Optional; Callback to perform chip specific operations when FRS * is sourcing vbus. + * @auto_discharge_disconnect: + * Optional; Enables TCPC to autonously discharge vbus on disconnect. */ -struct tcpci; struct tcpci_data { struct regmap *regmap; unsigned char TX_BUF_BYTE_x_hidden:1; + unsigned char auto_discharge_disconnect:1; + int (*init)(struct tcpci *tcpci, struct tcpci_data *data); int (*set_vconn)(struct tcpci *tcpci, struct tcpci_data *data, bool enable); -- 2.7.4