Commit e1a97bf8 authored by Badhri Jagan Sridharan's avatar Badhri Jagan Sridharan Committed by Greg Kroah-Hartman
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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: default avatarBadhri Jagan Sridharan <badhri@google.com>
Reviewed-by: default avatarHeikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20201029063138.1429760-9-badhri@google.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent f321a02c

drivers/usb/typec/tcpm/tcpci.c

+62 −1
Original line number Diff line number Diff line
@@ -19,6 +19,9 @@ 
#include "tcpci.h"



#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);

drivers/usb/typec/tcpm/tcpci.h

+12 −2
Original line number Diff line number Diff line
@@ -8,6 +8,8 @@ 
#ifndef __LINUX_USB_TCPCI_H

#define __LINUX_USB_TCPCI_H



#include <linux/usb/typec.h>



#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);